linux/net/sched/act_bpf.c

456 lines
10 KiB
C
Raw Normal View History

// SPDX-License-Identifier: GPL-2.0-or-later
/*
* Copyright (c) 2015 Jiri Pirko <jiri@resnulli.us>
*/
#include <linux/module.h>
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/skbuff.h>
#include <linux/rtnetlink.h>
#include <linux/filter.h>
#include <linux/bpf.h>
#include <net/netlink.h>
#include <net/sock.h>
#include <net/pkt_sched.h>
net/sched: act_bpf: validate the control action inside init() the following script: # tc filter add dev crash0 egress matchall \ > action bpf bytecode '1,6 0 0 4294967295' pass index 90 # tc actions replace action bpf \ > bytecode '1,6 0 0 4294967295' goto chain 42 index 90 cookie c1a0c1a0 # tc action show action bpf had the following output: Error: Failed to init TC action chain. We have an error talking to the kernel total acts 1 action order 0: bpf bytecode '1,6 0 0 4294967295' default-action goto chain 42 index 90 ref 2 bind 1 cookie c1a0c1a0 Then, the first packet transmitted by crash0 made the kernel crash: RIP: 0010:tcf_action_exec+0xb8/0x100 Code: 00 00 00 20 74 1d 83 f8 03 75 09 49 83 c4 08 4d 39 ec 75 bc 48 83 c4 10 5b 5d 41 5c 41 5d 41 5e 41 5f c3 49 8b 97 a8 00 00 00 <48> 8b 12 48 89 55 00 48 83 c4 10 5b 5d 41 5c 41 5d 41 5e 41 5f c3 RSP: 0018:ffffb3a0803dfa90 EFLAGS: 00010246 RAX: 000000002000002a RBX: ffff942b347ada00 RCX: 0000000000000000 RDX: 0000000000000000 RSI: ffffb3a08034d038 RDI: ffff942b347ada00 RBP: ffffb3a0803dfb30 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: ffffb3a0803dfb0c R12: ffff942b3b682b00 R13: ffff942b3b682b08 R14: 0000000000000001 R15: ffff942b3b682f00 FS: 00007f6160a72740(0000) GS:ffff942b3da80000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000000 CR3: 00000000795a4002 CR4: 00000000001606e0 Call Trace: tcf_classify+0x58/0x120 __dev_queue_xmit+0x40a/0x890 ? ip_finish_output2+0x16f/0x430 ip_finish_output2+0x16f/0x430 ? ip_output+0x69/0xe0 ip_output+0x69/0xe0 ? ip_forward_options+0x1a0/0x1a0 ip_send_skb+0x15/0x40 raw_sendmsg+0x8e1/0xbd0 ? sched_clock+0x5/0x10 ? sched_clock_cpu+0xc/0xa0 ? try_to_wake_up+0x54/0x480 ? ldsem_down_read+0x3f/0x280 ? _cond_resched+0x15/0x40 ? down_read+0xe/0x30 ? copy_termios+0x1e/0x70 ? tty_mode_ioctl+0x1b6/0x4c0 ? sock_sendmsg+0x36/0x40 sock_sendmsg+0x36/0x40 __sys_sendto+0x10e/0x140 ? do_vfs_ioctl+0xa4/0x640 ? handle_mm_fault+0xdc/0x210 ? syscall_trace_enter+0x1df/0x2e0 ? __audit_syscall_exit+0x216/0x260 __x64_sys_sendto+0x24/0x30 do_syscall_64+0x5b/0x180 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x7f615f7e3c03 Code: 48 8b 0d 90 62 2c 00 f7 d8 64 89 01 48 83 c8 ff c3 66 0f 1f 44 00 00 83 3d 9d c3 2c 00 00 75 13 49 89 ca b8 2c 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 34 c3 48 83 ec 08 e8 4b cc 00 00 48 89 04 24 RSP: 002b:00007ffee5d8cc28 EFLAGS: 00000246 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 000055a4f28f1700 RCX: 00007f615f7e3c03 RDX: 0000000000000040 RSI: 000055a4f28f1700 RDI: 0000000000000003 RBP: 00007ffee5d8e340 R08: 000055a4f28ee510 R09: 0000000000000010 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000040 R13: 000055a4f28f16c0 R14: 000055a4f28ef69c R15: 0000000000000080 Modules linked in: act_bpf veth ip6table_filter ip6_tables iptable_filter binfmt_misc ext4 mbcache crct10dif_pclmul jbd2 crc32_pclmul snd_hda_codec_generic ghash_clmulni_intel snd_hda_intel snd_hda_codec snd_hwdep snd_hda_core snd_seq snd_seq_device snd_pcm aesni_intel crypto_simd cryptd glue_helper pcspkr joydev virtio_balloon snd_timer snd i2c_piix4 soundcore nfsd auth_rpcgss nfs_acl lockd grace sunrpc ip_tables xfs ata_generic pata_acpi qxl drm_kms_helper virtio_blk virtio_net virtio_console net_failover failover syscopyarea sysfillrect sysimgblt fb_sys_fops ttm drm crc32c_intel ata_piix serio_raw libata virtio_pci virtio_ring virtio floppy dm_mirror dm_region_hash dm_log dm_mod CR2: 0000000000000000 Validating the control action within tcf_bpf_init() proved to fix the above issue. A TDC selftest is added to verify the correct behavior. Fixes: db50514f9a9c ("net: sched: add termination action to allow goto chain") Fixes: 97763dc0f401 ("net_sched: reject unknown tcfa_action values") Signed-off-by: Davide Caratti <dcaratti@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-03-20 22:00:00 +08:00
#include <net/pkt_cls.h>
#include <linux/tc_act/tc_bpf.h>
#include <net/tc_act/tc_bpf.h>
#define ACT_BPF_NAME_LEN 256
struct tcf_bpf_cfg {
struct bpf_prog *filter;
struct sock_filter *bpf_ops;
act_bpf: fix memory leaks when replacing bpf programs We currently trigger multiple memory leaks when replacing bpf actions, besides others: comm "tc", pid 1909, jiffies 4294851310 (age 1602.796s) hex dump (first 32 bytes): 01 00 00 00 03 00 00 00 00 00 00 00 00 00 00 00 ................ 18 b0 98 6d 00 88 ff ff 00 00 00 00 00 00 00 00 ...m............ backtrace: [<ffffffff817e623e>] kmemleak_alloc+0x4e/0xb0 [<ffffffff8120a22d>] __vmalloc_node_range+0x1bd/0x2c0 [<ffffffff8120a37a>] __vmalloc+0x4a/0x50 [<ffffffff811a8d0a>] bpf_prog_alloc+0x3a/0xa0 [<ffffffff816c0684>] bpf_prog_create+0x44/0xa0 [<ffffffffa09ba4eb>] tcf_bpf_init+0x28b/0x3c0 [act_bpf] [<ffffffff816d7001>] tcf_action_init_1+0x191/0x1b0 [<ffffffff816d70a2>] tcf_action_init+0x82/0xf0 [<ffffffff816d4d12>] tcf_exts_validate+0xb2/0xc0 [<ffffffffa09b5838>] cls_bpf_modify_existing+0x98/0x340 [cls_bpf] [<ffffffffa09b5cd6>] cls_bpf_change+0x1a6/0x274 [cls_bpf] [<ffffffff816d56e5>] tc_ctl_tfilter+0x335/0x910 [<ffffffff816b9145>] rtnetlink_rcv_msg+0x95/0x240 [<ffffffff816df34f>] netlink_rcv_skb+0xaf/0xc0 [<ffffffff816b909e>] rtnetlink_rcv+0x2e/0x40 [<ffffffff816deaaf>] netlink_unicast+0xef/0x1b0 Issue is that the old content from tcf_bpf is allocated and needs to be released when we replace it. We seem to do that since the beginning of act_bpf on the filter and insns, later on the name as well. Example test case, after patch: # FOO="1,6 0 0 4294967295," # BAR="1,6 0 0 4294967294," # tc actions add action bpf bytecode "$FOO" index 2 # tc actions show action bpf action order 0: bpf bytecode '1,6 0 0 4294967295' default-action pipe index 2 ref 1 bind 0 # tc actions replace action bpf bytecode "$BAR" index 2 # tc actions show action bpf action order 0: bpf bytecode '1,6 0 0 4294967294' default-action pipe index 2 ref 1 bind 0 # tc actions replace action bpf bytecode "$FOO" index 2 # tc actions show action bpf action order 0: bpf bytecode '1,6 0 0 4294967295' default-action pipe index 2 ref 1 bind 0 # tc actions del action bpf index 2 [...] # echo "scan" > /sys/kernel/debug/kmemleak # cat /sys/kernel/debug/kmemleak | grep "comm \"tc\"" | wc -l 0 Fixes: d23b8ad8ab23 ("tc: add BPF based action") Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-07-30 00:40:56 +08:00
const char *bpf_name;
u16 bpf_num_ops;
act_bpf: fix memory leaks when replacing bpf programs We currently trigger multiple memory leaks when replacing bpf actions, besides others: comm "tc", pid 1909, jiffies 4294851310 (age 1602.796s) hex dump (first 32 bytes): 01 00 00 00 03 00 00 00 00 00 00 00 00 00 00 00 ................ 18 b0 98 6d 00 88 ff ff 00 00 00 00 00 00 00 00 ...m............ backtrace: [<ffffffff817e623e>] kmemleak_alloc+0x4e/0xb0 [<ffffffff8120a22d>] __vmalloc_node_range+0x1bd/0x2c0 [<ffffffff8120a37a>] __vmalloc+0x4a/0x50 [<ffffffff811a8d0a>] bpf_prog_alloc+0x3a/0xa0 [<ffffffff816c0684>] bpf_prog_create+0x44/0xa0 [<ffffffffa09ba4eb>] tcf_bpf_init+0x28b/0x3c0 [act_bpf] [<ffffffff816d7001>] tcf_action_init_1+0x191/0x1b0 [<ffffffff816d70a2>] tcf_action_init+0x82/0xf0 [<ffffffff816d4d12>] tcf_exts_validate+0xb2/0xc0 [<ffffffffa09b5838>] cls_bpf_modify_existing+0x98/0x340 [cls_bpf] [<ffffffffa09b5cd6>] cls_bpf_change+0x1a6/0x274 [cls_bpf] [<ffffffff816d56e5>] tc_ctl_tfilter+0x335/0x910 [<ffffffff816b9145>] rtnetlink_rcv_msg+0x95/0x240 [<ffffffff816df34f>] netlink_rcv_skb+0xaf/0xc0 [<ffffffff816b909e>] rtnetlink_rcv+0x2e/0x40 [<ffffffff816deaaf>] netlink_unicast+0xef/0x1b0 Issue is that the old content from tcf_bpf is allocated and needs to be released when we replace it. We seem to do that since the beginning of act_bpf on the filter and insns, later on the name as well. Example test case, after patch: # FOO="1,6 0 0 4294967295," # BAR="1,6 0 0 4294967294," # tc actions add action bpf bytecode "$FOO" index 2 # tc actions show action bpf action order 0: bpf bytecode '1,6 0 0 4294967295' default-action pipe index 2 ref 1 bind 0 # tc actions replace action bpf bytecode "$BAR" index 2 # tc actions show action bpf action order 0: bpf bytecode '1,6 0 0 4294967294' default-action pipe index 2 ref 1 bind 0 # tc actions replace action bpf bytecode "$FOO" index 2 # tc actions show action bpf action order 0: bpf bytecode '1,6 0 0 4294967295' default-action pipe index 2 ref 1 bind 0 # tc actions del action bpf index 2 [...] # echo "scan" > /sys/kernel/debug/kmemleak # cat /sys/kernel/debug/kmemleak | grep "comm \"tc\"" | wc -l 0 Fixes: d23b8ad8ab23 ("tc: add BPF based action") Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-07-30 00:40:56 +08:00
bool is_ebpf;
};
netns: make struct pernet_operations::id unsigned int Make struct pernet_operations::id unsigned. There are 2 reasons to do so: 1) This field is really an index into an zero based array and thus is unsigned entity. Using negative value is out-of-bound access by definition. 2) On x86_64 unsigned 32-bit data which are mixed with pointers via array indexing or offsets added or subtracted to pointers are preffered to signed 32-bit data. "int" being used as an array index needs to be sign-extended to 64-bit before being used. void f(long *p, int i) { g(p[i]); } roughly translates to movsx rsi, esi mov rdi, [rsi+...] call g MOVSX is 3 byte instruction which isn't necessary if the variable is unsigned because x86_64 is zero extending by default. Now, there is net_generic() function which, you guessed it right, uses "int" as an array index: static inline void *net_generic(const struct net *net, int id) { ... ptr = ng->ptr[id - 1]; ... } And this function is used a lot, so those sign extensions add up. Patch snipes ~1730 bytes on allyesconfig kernel (without all junk messing with code generation): add/remove: 0/0 grow/shrink: 70/598 up/down: 396/-2126 (-1730) Unfortunately some functions actually grow bigger. This is a semmingly random artefact of code generation with register allocator being used differently. gcc decides that some variable needs to live in new r8+ registers and every access now requires REX prefix. Or it is shifted into r12, so [r12+0] addressing mode has to be used which is longer than [r8] However, overall balance is in negative direction: add/remove: 0/0 grow/shrink: 70/598 up/down: 396/-2126 (-1730) function old new delta nfsd4_lock 3886 3959 +73 tipc_link_build_proto_msg 1096 1140 +44 mac80211_hwsim_new_radio 2776 2808 +32 tipc_mon_rcv 1032 1058 +26 svcauth_gss_legacy_init 1413 1429 +16 tipc_bcbase_select_primary 379 392 +13 nfsd4_exchange_id 1247 1260 +13 nfsd4_setclientid_confirm 782 793 +11 ... put_client_renew_locked 494 480 -14 ip_set_sockfn_get 730 716 -14 geneve_sock_add 829 813 -16 nfsd4_sequence_done 721 703 -18 nlmclnt_lookup_host 708 686 -22 nfsd4_lockt 1085 1063 -22 nfs_get_client 1077 1050 -27 tcf_bpf_init 1106 1076 -30 nfsd4_encode_fattr 5997 5930 -67 Total: Before=154856051, After=154854321, chg -0.00% Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-11-17 09:58:21 +08:00
static unsigned int bpf_net_id;
static struct tc_action_ops act_bpf_ops;
static int tcf_bpf_act(struct sk_buff *skb, const struct tc_action *act,
struct tcf_result *res)
{
bool at_ingress = skb_at_tc_ingress(skb);
struct tcf_bpf *prog = to_bpf(act);
struct bpf_prog *filter;
act_bpf: allow non-default TC_ACT opcodes as BPF exec outcome Revisiting commit d23b8ad8ab23 ("tc: add BPF based action") with regards to eBPF support, I was thinking that it might be better to improve return semantics from a BPF program invoked through BPF_PROG_RUN(). Currently, in case filter_res is 0, we overwrite the default action opcode with TC_ACT_SHOT. A default action opcode configured through tc's m_bpf can be: TC_ACT_RECLASSIFY, TC_ACT_PIPE, TC_ACT_SHOT, TC_ACT_UNSPEC, TC_ACT_OK. In cls_bpf, we have the possibility to overwrite the default class associated with the classifier in case filter_res is _not_ 0xffffffff (-1). That allows us to fold multiple [e]BPF programs into a single one, where they would otherwise need to be defined as a separate classifier with its own classid, needlessly redoing parsing work, etc. Similarly, we could do better in act_bpf: Since above TC_ACT* opcodes are exported to UAPI anyway, we reuse them for return-code-to-tc-opcode mapping, where we would allow above possibilities. Thus, like in cls_bpf, a filter_res of 0xffffffff (-1) means that the configured _default_ action is used. Any unkown return code from the BPF program would fail in tcf_bpf() with TC_ACT_UNSPEC. Should we one day want to make use of TC_ACT_STOLEN or TC_ACT_QUEUED, which both have the same semantics, we have the option to either use that as a default action (filter_res of 0xffffffff) or non-default BPF return code. All that will allow us to transparently use tcf_bpf() for both BPF flavours. Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Cc: Jiri Pirko <jiri@resnulli.us> Cc: Alexei Starovoitov <ast@plumgrid.com> Cc: Jamal Hadi Salim <jhs@mojatatu.com> Acked-by: Jiri Pirko <jiri@resnulli.us> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-03-18 03:25:57 +08:00
int action, filter_res;
tcf_lastuse_update(&prog->tcf_tm);
bstats_update(this_cpu_ptr(prog->common.cpu_bstats), skb);
filter = rcu_dereference(prog->filter);
if (at_ingress) {
__skb_push(skb, skb->mac_len);
bpf_compute_data_pointers(skb);
filter_res = bpf_prog_run(filter, skb);
__skb_pull(skb, skb->mac_len);
} else {
bpf_compute_data_pointers(skb);
filter_res = bpf_prog_run(filter, skb);
}
if (skb_sk_is_prefetched(skb) && filter_res != TC_ACT_OK)
skb_orphan(skb);
act_bpf: allow non-default TC_ACT opcodes as BPF exec outcome Revisiting commit d23b8ad8ab23 ("tc: add BPF based action") with regards to eBPF support, I was thinking that it might be better to improve return semantics from a BPF program invoked through BPF_PROG_RUN(). Currently, in case filter_res is 0, we overwrite the default action opcode with TC_ACT_SHOT. A default action opcode configured through tc's m_bpf can be: TC_ACT_RECLASSIFY, TC_ACT_PIPE, TC_ACT_SHOT, TC_ACT_UNSPEC, TC_ACT_OK. In cls_bpf, we have the possibility to overwrite the default class associated with the classifier in case filter_res is _not_ 0xffffffff (-1). That allows us to fold multiple [e]BPF programs into a single one, where they would otherwise need to be defined as a separate classifier with its own classid, needlessly redoing parsing work, etc. Similarly, we could do better in act_bpf: Since above TC_ACT* opcodes are exported to UAPI anyway, we reuse them for return-code-to-tc-opcode mapping, where we would allow above possibilities. Thus, like in cls_bpf, a filter_res of 0xffffffff (-1) means that the configured _default_ action is used. Any unkown return code from the BPF program would fail in tcf_bpf() with TC_ACT_UNSPEC. Should we one day want to make use of TC_ACT_STOLEN or TC_ACT_QUEUED, which both have the same semantics, we have the option to either use that as a default action (filter_res of 0xffffffff) or non-default BPF return code. All that will allow us to transparently use tcf_bpf() for both BPF flavours. Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Cc: Jiri Pirko <jiri@resnulli.us> Cc: Alexei Starovoitov <ast@plumgrid.com> Cc: Jamal Hadi Salim <jhs@mojatatu.com> Acked-by: Jiri Pirko <jiri@resnulli.us> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-03-18 03:25:57 +08:00
/* A BPF program may overwrite the default action opcode.
* Similarly as in cls_bpf, if filter_res == -1 we use the
* default action specified from tc.
*
* In case a different well-known TC_ACT opcode has been
* returned, it will overwrite the default one.
*
* For everything else that is unknown, TC_ACT_UNSPEC is
act_bpf: allow non-default TC_ACT opcodes as BPF exec outcome Revisiting commit d23b8ad8ab23 ("tc: add BPF based action") with regards to eBPF support, I was thinking that it might be better to improve return semantics from a BPF program invoked through BPF_PROG_RUN(). Currently, in case filter_res is 0, we overwrite the default action opcode with TC_ACT_SHOT. A default action opcode configured through tc's m_bpf can be: TC_ACT_RECLASSIFY, TC_ACT_PIPE, TC_ACT_SHOT, TC_ACT_UNSPEC, TC_ACT_OK. In cls_bpf, we have the possibility to overwrite the default class associated with the classifier in case filter_res is _not_ 0xffffffff (-1). That allows us to fold multiple [e]BPF programs into a single one, where they would otherwise need to be defined as a separate classifier with its own classid, needlessly redoing parsing work, etc. Similarly, we could do better in act_bpf: Since above TC_ACT* opcodes are exported to UAPI anyway, we reuse them for return-code-to-tc-opcode mapping, where we would allow above possibilities. Thus, like in cls_bpf, a filter_res of 0xffffffff (-1) means that the configured _default_ action is used. Any unkown return code from the BPF program would fail in tcf_bpf() with TC_ACT_UNSPEC. Should we one day want to make use of TC_ACT_STOLEN or TC_ACT_QUEUED, which both have the same semantics, we have the option to either use that as a default action (filter_res of 0xffffffff) or non-default BPF return code. All that will allow us to transparently use tcf_bpf() for both BPF flavours. Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Cc: Jiri Pirko <jiri@resnulli.us> Cc: Alexei Starovoitov <ast@plumgrid.com> Cc: Jamal Hadi Salim <jhs@mojatatu.com> Acked-by: Jiri Pirko <jiri@resnulli.us> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-03-18 03:25:57 +08:00
* returned.
*/
switch (filter_res) {
case TC_ACT_PIPE:
case TC_ACT_RECLASSIFY:
case TC_ACT_OK:
2015-09-16 14:05:43 +08:00
case TC_ACT_REDIRECT:
act_bpf: allow non-default TC_ACT opcodes as BPF exec outcome Revisiting commit d23b8ad8ab23 ("tc: add BPF based action") with regards to eBPF support, I was thinking that it might be better to improve return semantics from a BPF program invoked through BPF_PROG_RUN(). Currently, in case filter_res is 0, we overwrite the default action opcode with TC_ACT_SHOT. A default action opcode configured through tc's m_bpf can be: TC_ACT_RECLASSIFY, TC_ACT_PIPE, TC_ACT_SHOT, TC_ACT_UNSPEC, TC_ACT_OK. In cls_bpf, we have the possibility to overwrite the default class associated with the classifier in case filter_res is _not_ 0xffffffff (-1). That allows us to fold multiple [e]BPF programs into a single one, where they would otherwise need to be defined as a separate classifier with its own classid, needlessly redoing parsing work, etc. Similarly, we could do better in act_bpf: Since above TC_ACT* opcodes are exported to UAPI anyway, we reuse them for return-code-to-tc-opcode mapping, where we would allow above possibilities. Thus, like in cls_bpf, a filter_res of 0xffffffff (-1) means that the configured _default_ action is used. Any unkown return code from the BPF program would fail in tcf_bpf() with TC_ACT_UNSPEC. Should we one day want to make use of TC_ACT_STOLEN or TC_ACT_QUEUED, which both have the same semantics, we have the option to either use that as a default action (filter_res of 0xffffffff) or non-default BPF return code. All that will allow us to transparently use tcf_bpf() for both BPF flavours. Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Cc: Jiri Pirko <jiri@resnulli.us> Cc: Alexei Starovoitov <ast@plumgrid.com> Cc: Jamal Hadi Salim <jhs@mojatatu.com> Acked-by: Jiri Pirko <jiri@resnulli.us> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-03-18 03:25:57 +08:00
action = filter_res;
break;
case TC_ACT_SHOT:
action = filter_res;
qstats_drop_inc(this_cpu_ptr(prog->common.cpu_qstats));
act_bpf: allow non-default TC_ACT opcodes as BPF exec outcome Revisiting commit d23b8ad8ab23 ("tc: add BPF based action") with regards to eBPF support, I was thinking that it might be better to improve return semantics from a BPF program invoked through BPF_PROG_RUN(). Currently, in case filter_res is 0, we overwrite the default action opcode with TC_ACT_SHOT. A default action opcode configured through tc's m_bpf can be: TC_ACT_RECLASSIFY, TC_ACT_PIPE, TC_ACT_SHOT, TC_ACT_UNSPEC, TC_ACT_OK. In cls_bpf, we have the possibility to overwrite the default class associated with the classifier in case filter_res is _not_ 0xffffffff (-1). That allows us to fold multiple [e]BPF programs into a single one, where they would otherwise need to be defined as a separate classifier with its own classid, needlessly redoing parsing work, etc. Similarly, we could do better in act_bpf: Since above TC_ACT* opcodes are exported to UAPI anyway, we reuse them for return-code-to-tc-opcode mapping, where we would allow above possibilities. Thus, like in cls_bpf, a filter_res of 0xffffffff (-1) means that the configured _default_ action is used. Any unkown return code from the BPF program would fail in tcf_bpf() with TC_ACT_UNSPEC. Should we one day want to make use of TC_ACT_STOLEN or TC_ACT_QUEUED, which both have the same semantics, we have the option to either use that as a default action (filter_res of 0xffffffff) or non-default BPF return code. All that will allow us to transparently use tcf_bpf() for both BPF flavours. Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Cc: Jiri Pirko <jiri@resnulli.us> Cc: Alexei Starovoitov <ast@plumgrid.com> Cc: Jamal Hadi Salim <jhs@mojatatu.com> Acked-by: Jiri Pirko <jiri@resnulli.us> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-03-18 03:25:57 +08:00
break;
case TC_ACT_UNSPEC:
action = prog->tcf_action;
act_bpf: allow non-default TC_ACT opcodes as BPF exec outcome Revisiting commit d23b8ad8ab23 ("tc: add BPF based action") with regards to eBPF support, I was thinking that it might be better to improve return semantics from a BPF program invoked through BPF_PROG_RUN(). Currently, in case filter_res is 0, we overwrite the default action opcode with TC_ACT_SHOT. A default action opcode configured through tc's m_bpf can be: TC_ACT_RECLASSIFY, TC_ACT_PIPE, TC_ACT_SHOT, TC_ACT_UNSPEC, TC_ACT_OK. In cls_bpf, we have the possibility to overwrite the default class associated with the classifier in case filter_res is _not_ 0xffffffff (-1). That allows us to fold multiple [e]BPF programs into a single one, where they would otherwise need to be defined as a separate classifier with its own classid, needlessly redoing parsing work, etc. Similarly, we could do better in act_bpf: Since above TC_ACT* opcodes are exported to UAPI anyway, we reuse them for return-code-to-tc-opcode mapping, where we would allow above possibilities. Thus, like in cls_bpf, a filter_res of 0xffffffff (-1) means that the configured _default_ action is used. Any unkown return code from the BPF program would fail in tcf_bpf() with TC_ACT_UNSPEC. Should we one day want to make use of TC_ACT_STOLEN or TC_ACT_QUEUED, which both have the same semantics, we have the option to either use that as a default action (filter_res of 0xffffffff) or non-default BPF return code. All that will allow us to transparently use tcf_bpf() for both BPF flavours. Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Cc: Jiri Pirko <jiri@resnulli.us> Cc: Alexei Starovoitov <ast@plumgrid.com> Cc: Jamal Hadi Salim <jhs@mojatatu.com> Acked-by: Jiri Pirko <jiri@resnulli.us> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-03-18 03:25:57 +08:00
break;
default:
action = TC_ACT_UNSPEC;
break;
}
return action;
}
static bool tcf_bpf_is_ebpf(const struct tcf_bpf *prog)
{
return !prog->bpf_ops;
}
static int tcf_bpf_dump_bpf_info(const struct tcf_bpf *prog,
struct sk_buff *skb)
{
struct nlattr *nla;
if (nla_put_u16(skb, TCA_ACT_BPF_OPS_LEN, prog->bpf_num_ops))
return -EMSGSIZE;
nla = nla_reserve(skb, TCA_ACT_BPF_OPS, prog->bpf_num_ops *
sizeof(struct sock_filter));
if (nla == NULL)
return -EMSGSIZE;
memcpy(nla_data(nla), prog->bpf_ops, nla_len(nla));
return 0;
}
static int tcf_bpf_dump_ebpf_info(const struct tcf_bpf *prog,
struct sk_buff *skb)
{
struct nlattr *nla;
if (prog->bpf_name &&
nla_put_string(skb, TCA_ACT_BPF_NAME, prog->bpf_name))
return -EMSGSIZE;
if (nla_put_u32(skb, TCA_ACT_BPF_ID, prog->filter->aux->id))
return -EMSGSIZE;
bpf: rework prog_digest into prog_tag Commit 7bd509e311f4 ("bpf: add prog_digest and expose it via fdinfo/netlink") was recently discussed, partially due to admittedly suboptimal name of "prog_digest" in combination with sha1 hash usage, thus inevitably and rightfully concerns about its security in terms of collision resistance were raised with regards to use-cases. The intended use cases are for debugging resp. introspection only for providing a stable "tag" over the instruction sequence that both kernel and user space can calculate independently. It's not usable at all for making a security relevant decision. So collisions where two different instruction sequences generate the same tag can happen, but ideally at a rather low rate. The "tag" will be dumped in hex and is short enough to introspect in tracepoints or kallsyms output along with other data such as stack trace, etc. Thus, this patch performs a rename into prog_tag and truncates the tag to a short output (64 bits) to make it obvious it's not collision-free. Should in future a hash or facility be needed with a security relevant focus, then we can think about requirements, constraints, etc that would fit to that situation. For now, rework the exposed parts for the current use cases as long as nothing has been released yet. Tested on x86_64 and s390x. Fixes: 7bd509e311f4 ("bpf: add prog_digest and expose it via fdinfo/netlink") Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Alexei Starovoitov <ast@kernel.org> Cc: Andy Lutomirski <luto@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-01-14 06:38:15 +08:00
nla = nla_reserve(skb, TCA_ACT_BPF_TAG, sizeof(prog->filter->tag));
if (nla == NULL)
return -EMSGSIZE;
bpf: rework prog_digest into prog_tag Commit 7bd509e311f4 ("bpf: add prog_digest and expose it via fdinfo/netlink") was recently discussed, partially due to admittedly suboptimal name of "prog_digest" in combination with sha1 hash usage, thus inevitably and rightfully concerns about its security in terms of collision resistance were raised with regards to use-cases. The intended use cases are for debugging resp. introspection only for providing a stable "tag" over the instruction sequence that both kernel and user space can calculate independently. It's not usable at all for making a security relevant decision. So collisions where two different instruction sequences generate the same tag can happen, but ideally at a rather low rate. The "tag" will be dumped in hex and is short enough to introspect in tracepoints or kallsyms output along with other data such as stack trace, etc. Thus, this patch performs a rename into prog_tag and truncates the tag to a short output (64 bits) to make it obvious it's not collision-free. Should in future a hash or facility be needed with a security relevant focus, then we can think about requirements, constraints, etc that would fit to that situation. For now, rework the exposed parts for the current use cases as long as nothing has been released yet. Tested on x86_64 and s390x. Fixes: 7bd509e311f4 ("bpf: add prog_digest and expose it via fdinfo/netlink") Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Alexei Starovoitov <ast@kernel.org> Cc: Andy Lutomirski <luto@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-01-14 06:38:15 +08:00
memcpy(nla_data(nla), prog->filter->tag, nla_len(nla));
return 0;
}
static int tcf_bpf_dump(struct sk_buff *skb, struct tc_action *act,
int bind, int ref)
{
unsigned char *tp = skb_tail_pointer(skb);
struct tcf_bpf *prog = to_bpf(act);
struct tc_act_bpf opt = {
.index = prog->tcf_index,
.refcnt = refcount_read(&prog->tcf_refcnt) - ref,
.bindcnt = atomic_read(&prog->tcf_bindcnt) - bind,
};
struct tcf_t tm;
int ret;
net: sched: always disable bh when taking tcf_lock Recently, ops->init() and ops->dump() of all actions were modified to always obtain tcf_lock when accessing private action state. Actions that don't depend on tcf_lock for synchronization with their data path use non-bh locking API. However, tcf_lock is also used to protect rate estimator stats in softirq context by timer callback. Change ops->init() and ops->dump() of all actions to disable bh when using tcf_lock to prevent deadlock reported by following lockdep warning: [ 105.470398] ================================ [ 105.475014] WARNING: inconsistent lock state [ 105.479628] 4.18.0-rc8+ #664 Not tainted [ 105.483897] -------------------------------- [ 105.488511] inconsistent {SOFTIRQ-ON-W} -> {IN-SOFTIRQ-W} usage. [ 105.494871] swapper/16/0 [HC0[0]:SC1[1]:HE1:SE0] takes: [ 105.500449] 00000000f86c012e (&(&p->tcfa_lock)->rlock){+.?.}, at: est_fetch_counters+0x3c/0xa0 [ 105.509696] {SOFTIRQ-ON-W} state was registered at: [ 105.514925] _raw_spin_lock+0x2c/0x40 [ 105.519022] tcf_bpf_init+0x579/0x820 [act_bpf] [ 105.523990] tcf_action_init_1+0x4e4/0x660 [ 105.528518] tcf_action_init+0x1ce/0x2d0 [ 105.532880] tcf_exts_validate+0x1d8/0x200 [ 105.537416] fl_change+0x55a/0x268b [cls_flower] [ 105.542469] tc_new_tfilter+0x748/0xa20 [ 105.546738] rtnetlink_rcv_msg+0x56a/0x6d0 [ 105.551268] netlink_rcv_skb+0x18d/0x200 [ 105.555628] netlink_unicast+0x2d0/0x370 [ 105.559990] netlink_sendmsg+0x3b9/0x6a0 [ 105.564349] sock_sendmsg+0x6b/0x80 [ 105.568271] ___sys_sendmsg+0x4a1/0x520 [ 105.572547] __sys_sendmsg+0xd7/0x150 [ 105.576655] do_syscall_64+0x72/0x2c0 [ 105.580757] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 105.586243] irq event stamp: 489296 [ 105.590084] hardirqs last enabled at (489296): [<ffffffffb507e639>] _raw_spin_unlock_irq+0x29/0x40 [ 105.599765] hardirqs last disabled at (489295): [<ffffffffb507e745>] _raw_spin_lock_irq+0x15/0x50 [ 105.609277] softirqs last enabled at (489292): [<ffffffffb413a6a3>] irq_enter+0x83/0xa0 [ 105.618001] softirqs last disabled at (489293): [<ffffffffb413a800>] irq_exit+0x140/0x190 [ 105.626813] other info that might help us debug this: [ 105.633976] Possible unsafe locking scenario: [ 105.640526] CPU0 [ 105.643325] ---- [ 105.646125] lock(&(&p->tcfa_lock)->rlock); [ 105.650747] <Interrupt> [ 105.653717] lock(&(&p->tcfa_lock)->rlock); [ 105.658514] *** DEADLOCK *** [ 105.665349] 1 lock held by swapper/16/0: [ 105.669629] #0: 00000000a640ad99 ((&est->timer)){+.-.}, at: call_timer_fn+0x10b/0x550 [ 105.678200] stack backtrace: [ 105.683194] CPU: 16 PID: 0 Comm: swapper/16 Not tainted 4.18.0-rc8+ #664 [ 105.690249] Hardware name: Supermicro SYS-2028TP-DECR/X10DRT-P, BIOS 2.0b 03/30/2017 [ 105.698626] Call Trace: [ 105.701421] <IRQ> [ 105.703791] dump_stack+0x92/0xeb [ 105.707461] print_usage_bug+0x336/0x34c [ 105.711744] mark_lock+0x7c9/0x980 [ 105.715500] ? print_shortest_lock_dependencies+0x2e0/0x2e0 [ 105.721424] ? check_usage_forwards+0x230/0x230 [ 105.726315] __lock_acquire+0x923/0x26f0 [ 105.730597] ? debug_show_all_locks+0x240/0x240 [ 105.735478] ? mark_lock+0x493/0x980 [ 105.739412] ? check_chain_key+0x140/0x1f0 [ 105.743861] ? __lock_acquire+0x836/0x26f0 [ 105.748323] ? lock_acquire+0x12e/0x290 [ 105.752516] lock_acquire+0x12e/0x290 [ 105.756539] ? est_fetch_counters+0x3c/0xa0 [ 105.761084] _raw_spin_lock+0x2c/0x40 [ 105.765099] ? est_fetch_counters+0x3c/0xa0 [ 105.769633] est_fetch_counters+0x3c/0xa0 [ 105.773995] est_timer+0x87/0x390 [ 105.777670] ? est_fetch_counters+0xa0/0xa0 [ 105.782210] ? lock_acquire+0x12e/0x290 [ 105.786410] call_timer_fn+0x161/0x550 [ 105.790512] ? est_fetch_counters+0xa0/0xa0 [ 105.795055] ? del_timer_sync+0xd0/0xd0 [ 105.799249] ? __lock_is_held+0x93/0x110 [ 105.803531] ? mark_held_locks+0x20/0xe0 [ 105.807813] ? _raw_spin_unlock_irq+0x29/0x40 [ 105.812525] ? est_fetch_counters+0xa0/0xa0 [ 105.817069] ? est_fetch_counters+0xa0/0xa0 [ 105.821610] run_timer_softirq+0x3c4/0x9f0 [ 105.826064] ? lock_acquire+0x12e/0x290 [ 105.830257] ? __bpf_trace_timer_class+0x10/0x10 [ 105.835237] ? __lock_is_held+0x25/0x110 [ 105.839517] __do_softirq+0x11d/0x7bf [ 105.843542] irq_exit+0x140/0x190 [ 105.847208] smp_apic_timer_interrupt+0xac/0x3b0 [ 105.852182] apic_timer_interrupt+0xf/0x20 [ 105.856628] </IRQ> [ 105.859081] RIP: 0010:cpuidle_enter_state+0xd8/0x4d0 [ 105.864395] Code: 46 ff 48 89 44 24 08 0f 1f 44 00 00 31 ff e8 cf ec 46 ff 80 7c 24 07 00 0f 85 1d 02 00 00 e8 9f 90 4b ff fb 66 0f 1f 44 00 00 <4c> 8b 6c 24 08 4d 29 fd 0f 80 36 03 00 00 4c 89 e8 48 ba cf f7 53 [ 105.884288] RSP: 0018:ffff8803ad94fd20 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff13 [ 105.892494] RAX: 0000000000000000 RBX: ffffe8fb300829c0 RCX: ffffffffb41e19e1 [ 105.899988] RDX: 0000000000000007 RSI: dffffc0000000000 RDI: ffff8803ad9358ac [ 105.907503] RBP: ffffffffb6636300 R08: 0000000000000004 R09: 0000000000000000 [ 105.914997] R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000004 [ 105.922487] R13: ffffffffb6636140 R14: ffffffffb66362d8 R15: 000000188d36091b [ 105.929988] ? trace_hardirqs_on_caller+0x141/0x2d0 [ 105.935232] do_idle+0x28e/0x320 [ 105.938817] ? arch_cpu_idle_exit+0x40/0x40 [ 105.943361] ? mark_lock+0x8c1/0x980 [ 105.947295] ? _raw_spin_unlock_irqrestore+0x32/0x60 [ 105.952619] cpu_startup_entry+0xc2/0xd0 [ 105.956900] ? cpu_in_idle+0x20/0x20 [ 105.960830] ? _raw_spin_unlock_irqrestore+0x32/0x60 [ 105.966146] ? trace_hardirqs_on_caller+0x141/0x2d0 [ 105.971391] start_secondary+0x2b5/0x360 [ 105.975669] ? set_cpu_sibling_map+0x1330/0x1330 [ 105.980654] secondary_startup_64+0xa5/0xb0 Taking tcf_lock in sample action with bh disabled causes lockdep to issue a warning regarding possible irq lock inversion dependency between tcf_lock, and psample_groups_lock that is taken when holding tcf_lock in sample init: [ 162.108959] Possible interrupt unsafe locking scenario: [ 162.116386] CPU0 CPU1 [ 162.121277] ---- ---- [ 162.126162] lock(psample_groups_lock); [ 162.130447] local_irq_disable(); [ 162.136772] lock(&(&p->tcfa_lock)->rlock); [ 162.143957] lock(psample_groups_lock); [ 162.150813] <Interrupt> [ 162.153808] lock(&(&p->tcfa_lock)->rlock); [ 162.158608] *** DEADLOCK *** In order to prevent potential lock inversion dependency between tcf_lock and psample_groups_lock, extract call to psample_group_get() from tcf_lock protected section in sample action init function. Fixes: 4e232818bd32 ("net: sched: act_mirred: remove dependency on rtnl lock") Fixes: 764e9a24480f ("net: sched: act_vlan: remove dependency on rtnl lock") Fixes: 729e01260989 ("net: sched: act_tunnel_key: remove dependency on rtnl lock") Fixes: d77284956656 ("net: sched: act_sample: remove dependency on rtnl lock") Fixes: e8917f437006 ("net: sched: act_gact: remove dependency on rtnl lock") Fixes: b6a2b971c0b0 ("net: sched: act_csum: remove dependency on rtnl lock") Fixes: 2142236b4584 ("net: sched: act_bpf: remove dependency on rtnl lock") Signed-off-by: Vlad Buslov <vladbu@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-08-15 02:46:16 +08:00
spin_lock_bh(&prog->tcf_lock);
opt.action = prog->tcf_action;
if (nla_put(skb, TCA_ACT_BPF_PARMS, sizeof(opt), &opt))
goto nla_put_failure;
if (tcf_bpf_is_ebpf(prog))
ret = tcf_bpf_dump_ebpf_info(prog, skb);
else
ret = tcf_bpf_dump_bpf_info(prog, skb);
if (ret)
goto nla_put_failure;
tcf_tm_dump(&tm, &prog->tcf_tm);
if (nla_put_64bit(skb, TCA_ACT_BPF_TM, sizeof(tm), &tm,
TCA_ACT_BPF_PAD))
goto nla_put_failure;
net: sched: always disable bh when taking tcf_lock Recently, ops->init() and ops->dump() of all actions were modified to always obtain tcf_lock when accessing private action state. Actions that don't depend on tcf_lock for synchronization with their data path use non-bh locking API. However, tcf_lock is also used to protect rate estimator stats in softirq context by timer callback. Change ops->init() and ops->dump() of all actions to disable bh when using tcf_lock to prevent deadlock reported by following lockdep warning: [ 105.470398] ================================ [ 105.475014] WARNING: inconsistent lock state [ 105.479628] 4.18.0-rc8+ #664 Not tainted [ 105.483897] -------------------------------- [ 105.488511] inconsistent {SOFTIRQ-ON-W} -> {IN-SOFTIRQ-W} usage. [ 105.494871] swapper/16/0 [HC0[0]:SC1[1]:HE1:SE0] takes: [ 105.500449] 00000000f86c012e (&(&p->tcfa_lock)->rlock){+.?.}, at: est_fetch_counters+0x3c/0xa0 [ 105.509696] {SOFTIRQ-ON-W} state was registered at: [ 105.514925] _raw_spin_lock+0x2c/0x40 [ 105.519022] tcf_bpf_init+0x579/0x820 [act_bpf] [ 105.523990] tcf_action_init_1+0x4e4/0x660 [ 105.528518] tcf_action_init+0x1ce/0x2d0 [ 105.532880] tcf_exts_validate+0x1d8/0x200 [ 105.537416] fl_change+0x55a/0x268b [cls_flower] [ 105.542469] tc_new_tfilter+0x748/0xa20 [ 105.546738] rtnetlink_rcv_msg+0x56a/0x6d0 [ 105.551268] netlink_rcv_skb+0x18d/0x200 [ 105.555628] netlink_unicast+0x2d0/0x370 [ 105.559990] netlink_sendmsg+0x3b9/0x6a0 [ 105.564349] sock_sendmsg+0x6b/0x80 [ 105.568271] ___sys_sendmsg+0x4a1/0x520 [ 105.572547] __sys_sendmsg+0xd7/0x150 [ 105.576655] do_syscall_64+0x72/0x2c0 [ 105.580757] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 105.586243] irq event stamp: 489296 [ 105.590084] hardirqs last enabled at (489296): [<ffffffffb507e639>] _raw_spin_unlock_irq+0x29/0x40 [ 105.599765] hardirqs last disabled at (489295): [<ffffffffb507e745>] _raw_spin_lock_irq+0x15/0x50 [ 105.609277] softirqs last enabled at (489292): [<ffffffffb413a6a3>] irq_enter+0x83/0xa0 [ 105.618001] softirqs last disabled at (489293): [<ffffffffb413a800>] irq_exit+0x140/0x190 [ 105.626813] other info that might help us debug this: [ 105.633976] Possible unsafe locking scenario: [ 105.640526] CPU0 [ 105.643325] ---- [ 105.646125] lock(&(&p->tcfa_lock)->rlock); [ 105.650747] <Interrupt> [ 105.653717] lock(&(&p->tcfa_lock)->rlock); [ 105.658514] *** DEADLOCK *** [ 105.665349] 1 lock held by swapper/16/0: [ 105.669629] #0: 00000000a640ad99 ((&est->timer)){+.-.}, at: call_timer_fn+0x10b/0x550 [ 105.678200] stack backtrace: [ 105.683194] CPU: 16 PID: 0 Comm: swapper/16 Not tainted 4.18.0-rc8+ #664 [ 105.690249] Hardware name: Supermicro SYS-2028TP-DECR/X10DRT-P, BIOS 2.0b 03/30/2017 [ 105.698626] Call Trace: [ 105.701421] <IRQ> [ 105.703791] dump_stack+0x92/0xeb [ 105.707461] print_usage_bug+0x336/0x34c [ 105.711744] mark_lock+0x7c9/0x980 [ 105.715500] ? print_shortest_lock_dependencies+0x2e0/0x2e0 [ 105.721424] ? check_usage_forwards+0x230/0x230 [ 105.726315] __lock_acquire+0x923/0x26f0 [ 105.730597] ? debug_show_all_locks+0x240/0x240 [ 105.735478] ? mark_lock+0x493/0x980 [ 105.739412] ? check_chain_key+0x140/0x1f0 [ 105.743861] ? __lock_acquire+0x836/0x26f0 [ 105.748323] ? lock_acquire+0x12e/0x290 [ 105.752516] lock_acquire+0x12e/0x290 [ 105.756539] ? est_fetch_counters+0x3c/0xa0 [ 105.761084] _raw_spin_lock+0x2c/0x40 [ 105.765099] ? est_fetch_counters+0x3c/0xa0 [ 105.769633] est_fetch_counters+0x3c/0xa0 [ 105.773995] est_timer+0x87/0x390 [ 105.777670] ? est_fetch_counters+0xa0/0xa0 [ 105.782210] ? lock_acquire+0x12e/0x290 [ 105.786410] call_timer_fn+0x161/0x550 [ 105.790512] ? est_fetch_counters+0xa0/0xa0 [ 105.795055] ? del_timer_sync+0xd0/0xd0 [ 105.799249] ? __lock_is_held+0x93/0x110 [ 105.803531] ? mark_held_locks+0x20/0xe0 [ 105.807813] ? _raw_spin_unlock_irq+0x29/0x40 [ 105.812525] ? est_fetch_counters+0xa0/0xa0 [ 105.817069] ? est_fetch_counters+0xa0/0xa0 [ 105.821610] run_timer_softirq+0x3c4/0x9f0 [ 105.826064] ? lock_acquire+0x12e/0x290 [ 105.830257] ? __bpf_trace_timer_class+0x10/0x10 [ 105.835237] ? __lock_is_held+0x25/0x110 [ 105.839517] __do_softirq+0x11d/0x7bf [ 105.843542] irq_exit+0x140/0x190 [ 105.847208] smp_apic_timer_interrupt+0xac/0x3b0 [ 105.852182] apic_timer_interrupt+0xf/0x20 [ 105.856628] </IRQ> [ 105.859081] RIP: 0010:cpuidle_enter_state+0xd8/0x4d0 [ 105.864395] Code: 46 ff 48 89 44 24 08 0f 1f 44 00 00 31 ff e8 cf ec 46 ff 80 7c 24 07 00 0f 85 1d 02 00 00 e8 9f 90 4b ff fb 66 0f 1f 44 00 00 <4c> 8b 6c 24 08 4d 29 fd 0f 80 36 03 00 00 4c 89 e8 48 ba cf f7 53 [ 105.884288] RSP: 0018:ffff8803ad94fd20 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff13 [ 105.892494] RAX: 0000000000000000 RBX: ffffe8fb300829c0 RCX: ffffffffb41e19e1 [ 105.899988] RDX: 0000000000000007 RSI: dffffc0000000000 RDI: ffff8803ad9358ac [ 105.907503] RBP: ffffffffb6636300 R08: 0000000000000004 R09: 0000000000000000 [ 105.914997] R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000004 [ 105.922487] R13: ffffffffb6636140 R14: ffffffffb66362d8 R15: 000000188d36091b [ 105.929988] ? trace_hardirqs_on_caller+0x141/0x2d0 [ 105.935232] do_idle+0x28e/0x320 [ 105.938817] ? arch_cpu_idle_exit+0x40/0x40 [ 105.943361] ? mark_lock+0x8c1/0x980 [ 105.947295] ? _raw_spin_unlock_irqrestore+0x32/0x60 [ 105.952619] cpu_startup_entry+0xc2/0xd0 [ 105.956900] ? cpu_in_idle+0x20/0x20 [ 105.960830] ? _raw_spin_unlock_irqrestore+0x32/0x60 [ 105.966146] ? trace_hardirqs_on_caller+0x141/0x2d0 [ 105.971391] start_secondary+0x2b5/0x360 [ 105.975669] ? set_cpu_sibling_map+0x1330/0x1330 [ 105.980654] secondary_startup_64+0xa5/0xb0 Taking tcf_lock in sample action with bh disabled causes lockdep to issue a warning regarding possible irq lock inversion dependency between tcf_lock, and psample_groups_lock that is taken when holding tcf_lock in sample init: [ 162.108959] Possible interrupt unsafe locking scenario: [ 162.116386] CPU0 CPU1 [ 162.121277] ---- ---- [ 162.126162] lock(psample_groups_lock); [ 162.130447] local_irq_disable(); [ 162.136772] lock(&(&p->tcfa_lock)->rlock); [ 162.143957] lock(psample_groups_lock); [ 162.150813] <Interrupt> [ 162.153808] lock(&(&p->tcfa_lock)->rlock); [ 162.158608] *** DEADLOCK *** In order to prevent potential lock inversion dependency between tcf_lock and psample_groups_lock, extract call to psample_group_get() from tcf_lock protected section in sample action init function. Fixes: 4e232818bd32 ("net: sched: act_mirred: remove dependency on rtnl lock") Fixes: 764e9a24480f ("net: sched: act_vlan: remove dependency on rtnl lock") Fixes: 729e01260989 ("net: sched: act_tunnel_key: remove dependency on rtnl lock") Fixes: d77284956656 ("net: sched: act_sample: remove dependency on rtnl lock") Fixes: e8917f437006 ("net: sched: act_gact: remove dependency on rtnl lock") Fixes: b6a2b971c0b0 ("net: sched: act_csum: remove dependency on rtnl lock") Fixes: 2142236b4584 ("net: sched: act_bpf: remove dependency on rtnl lock") Signed-off-by: Vlad Buslov <vladbu@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-08-15 02:46:16 +08:00
spin_unlock_bh(&prog->tcf_lock);
return skb->len;
nla_put_failure:
net: sched: always disable bh when taking tcf_lock Recently, ops->init() and ops->dump() of all actions were modified to always obtain tcf_lock when accessing private action state. Actions that don't depend on tcf_lock for synchronization with their data path use non-bh locking API. However, tcf_lock is also used to protect rate estimator stats in softirq context by timer callback. Change ops->init() and ops->dump() of all actions to disable bh when using tcf_lock to prevent deadlock reported by following lockdep warning: [ 105.470398] ================================ [ 105.475014] WARNING: inconsistent lock state [ 105.479628] 4.18.0-rc8+ #664 Not tainted [ 105.483897] -------------------------------- [ 105.488511] inconsistent {SOFTIRQ-ON-W} -> {IN-SOFTIRQ-W} usage. [ 105.494871] swapper/16/0 [HC0[0]:SC1[1]:HE1:SE0] takes: [ 105.500449] 00000000f86c012e (&(&p->tcfa_lock)->rlock){+.?.}, at: est_fetch_counters+0x3c/0xa0 [ 105.509696] {SOFTIRQ-ON-W} state was registered at: [ 105.514925] _raw_spin_lock+0x2c/0x40 [ 105.519022] tcf_bpf_init+0x579/0x820 [act_bpf] [ 105.523990] tcf_action_init_1+0x4e4/0x660 [ 105.528518] tcf_action_init+0x1ce/0x2d0 [ 105.532880] tcf_exts_validate+0x1d8/0x200 [ 105.537416] fl_change+0x55a/0x268b [cls_flower] [ 105.542469] tc_new_tfilter+0x748/0xa20 [ 105.546738] rtnetlink_rcv_msg+0x56a/0x6d0 [ 105.551268] netlink_rcv_skb+0x18d/0x200 [ 105.555628] netlink_unicast+0x2d0/0x370 [ 105.559990] netlink_sendmsg+0x3b9/0x6a0 [ 105.564349] sock_sendmsg+0x6b/0x80 [ 105.568271] ___sys_sendmsg+0x4a1/0x520 [ 105.572547] __sys_sendmsg+0xd7/0x150 [ 105.576655] do_syscall_64+0x72/0x2c0 [ 105.580757] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 105.586243] irq event stamp: 489296 [ 105.590084] hardirqs last enabled at (489296): [<ffffffffb507e639>] _raw_spin_unlock_irq+0x29/0x40 [ 105.599765] hardirqs last disabled at (489295): [<ffffffffb507e745>] _raw_spin_lock_irq+0x15/0x50 [ 105.609277] softirqs last enabled at (489292): [<ffffffffb413a6a3>] irq_enter+0x83/0xa0 [ 105.618001] softirqs last disabled at (489293): [<ffffffffb413a800>] irq_exit+0x140/0x190 [ 105.626813] other info that might help us debug this: [ 105.633976] Possible unsafe locking scenario: [ 105.640526] CPU0 [ 105.643325] ---- [ 105.646125] lock(&(&p->tcfa_lock)->rlock); [ 105.650747] <Interrupt> [ 105.653717] lock(&(&p->tcfa_lock)->rlock); [ 105.658514] *** DEADLOCK *** [ 105.665349] 1 lock held by swapper/16/0: [ 105.669629] #0: 00000000a640ad99 ((&est->timer)){+.-.}, at: call_timer_fn+0x10b/0x550 [ 105.678200] stack backtrace: [ 105.683194] CPU: 16 PID: 0 Comm: swapper/16 Not tainted 4.18.0-rc8+ #664 [ 105.690249] Hardware name: Supermicro SYS-2028TP-DECR/X10DRT-P, BIOS 2.0b 03/30/2017 [ 105.698626] Call Trace: [ 105.701421] <IRQ> [ 105.703791] dump_stack+0x92/0xeb [ 105.707461] print_usage_bug+0x336/0x34c [ 105.711744] mark_lock+0x7c9/0x980 [ 105.715500] ? print_shortest_lock_dependencies+0x2e0/0x2e0 [ 105.721424] ? check_usage_forwards+0x230/0x230 [ 105.726315] __lock_acquire+0x923/0x26f0 [ 105.730597] ? debug_show_all_locks+0x240/0x240 [ 105.735478] ? mark_lock+0x493/0x980 [ 105.739412] ? check_chain_key+0x140/0x1f0 [ 105.743861] ? __lock_acquire+0x836/0x26f0 [ 105.748323] ? lock_acquire+0x12e/0x290 [ 105.752516] lock_acquire+0x12e/0x290 [ 105.756539] ? est_fetch_counters+0x3c/0xa0 [ 105.761084] _raw_spin_lock+0x2c/0x40 [ 105.765099] ? est_fetch_counters+0x3c/0xa0 [ 105.769633] est_fetch_counters+0x3c/0xa0 [ 105.773995] est_timer+0x87/0x390 [ 105.777670] ? est_fetch_counters+0xa0/0xa0 [ 105.782210] ? lock_acquire+0x12e/0x290 [ 105.786410] call_timer_fn+0x161/0x550 [ 105.790512] ? est_fetch_counters+0xa0/0xa0 [ 105.795055] ? del_timer_sync+0xd0/0xd0 [ 105.799249] ? __lock_is_held+0x93/0x110 [ 105.803531] ? mark_held_locks+0x20/0xe0 [ 105.807813] ? _raw_spin_unlock_irq+0x29/0x40 [ 105.812525] ? est_fetch_counters+0xa0/0xa0 [ 105.817069] ? est_fetch_counters+0xa0/0xa0 [ 105.821610] run_timer_softirq+0x3c4/0x9f0 [ 105.826064] ? lock_acquire+0x12e/0x290 [ 105.830257] ? __bpf_trace_timer_class+0x10/0x10 [ 105.835237] ? __lock_is_held+0x25/0x110 [ 105.839517] __do_softirq+0x11d/0x7bf [ 105.843542] irq_exit+0x140/0x190 [ 105.847208] smp_apic_timer_interrupt+0xac/0x3b0 [ 105.852182] apic_timer_interrupt+0xf/0x20 [ 105.856628] </IRQ> [ 105.859081] RIP: 0010:cpuidle_enter_state+0xd8/0x4d0 [ 105.864395] Code: 46 ff 48 89 44 24 08 0f 1f 44 00 00 31 ff e8 cf ec 46 ff 80 7c 24 07 00 0f 85 1d 02 00 00 e8 9f 90 4b ff fb 66 0f 1f 44 00 00 <4c> 8b 6c 24 08 4d 29 fd 0f 80 36 03 00 00 4c 89 e8 48 ba cf f7 53 [ 105.884288] RSP: 0018:ffff8803ad94fd20 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff13 [ 105.892494] RAX: 0000000000000000 RBX: ffffe8fb300829c0 RCX: ffffffffb41e19e1 [ 105.899988] RDX: 0000000000000007 RSI: dffffc0000000000 RDI: ffff8803ad9358ac [ 105.907503] RBP: ffffffffb6636300 R08: 0000000000000004 R09: 0000000000000000 [ 105.914997] R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000004 [ 105.922487] R13: ffffffffb6636140 R14: ffffffffb66362d8 R15: 000000188d36091b [ 105.929988] ? trace_hardirqs_on_caller+0x141/0x2d0 [ 105.935232] do_idle+0x28e/0x320 [ 105.938817] ? arch_cpu_idle_exit+0x40/0x40 [ 105.943361] ? mark_lock+0x8c1/0x980 [ 105.947295] ? _raw_spin_unlock_irqrestore+0x32/0x60 [ 105.952619] cpu_startup_entry+0xc2/0xd0 [ 105.956900] ? cpu_in_idle+0x20/0x20 [ 105.960830] ? _raw_spin_unlock_irqrestore+0x32/0x60 [ 105.966146] ? trace_hardirqs_on_caller+0x141/0x2d0 [ 105.971391] start_secondary+0x2b5/0x360 [ 105.975669] ? set_cpu_sibling_map+0x1330/0x1330 [ 105.980654] secondary_startup_64+0xa5/0xb0 Taking tcf_lock in sample action with bh disabled causes lockdep to issue a warning regarding possible irq lock inversion dependency between tcf_lock, and psample_groups_lock that is taken when holding tcf_lock in sample init: [ 162.108959] Possible interrupt unsafe locking scenario: [ 162.116386] CPU0 CPU1 [ 162.121277] ---- ---- [ 162.126162] lock(psample_groups_lock); [ 162.130447] local_irq_disable(); [ 162.136772] lock(&(&p->tcfa_lock)->rlock); [ 162.143957] lock(psample_groups_lock); [ 162.150813] <Interrupt> [ 162.153808] lock(&(&p->tcfa_lock)->rlock); [ 162.158608] *** DEADLOCK *** In order to prevent potential lock inversion dependency between tcf_lock and psample_groups_lock, extract call to psample_group_get() from tcf_lock protected section in sample action init function. Fixes: 4e232818bd32 ("net: sched: act_mirred: remove dependency on rtnl lock") Fixes: 764e9a24480f ("net: sched: act_vlan: remove dependency on rtnl lock") Fixes: 729e01260989 ("net: sched: act_tunnel_key: remove dependency on rtnl lock") Fixes: d77284956656 ("net: sched: act_sample: remove dependency on rtnl lock") Fixes: e8917f437006 ("net: sched: act_gact: remove dependency on rtnl lock") Fixes: b6a2b971c0b0 ("net: sched: act_csum: remove dependency on rtnl lock") Fixes: 2142236b4584 ("net: sched: act_bpf: remove dependency on rtnl lock") Signed-off-by: Vlad Buslov <vladbu@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-08-15 02:46:16 +08:00
spin_unlock_bh(&prog->tcf_lock);
nlmsg_trim(skb, tp);
return -1;
}
static const struct nla_policy act_bpf_policy[TCA_ACT_BPF_MAX + 1] = {
[TCA_ACT_BPF_PARMS] = { .len = sizeof(struct tc_act_bpf) },
[TCA_ACT_BPF_FD] = { .type = NLA_U32 },
[TCA_ACT_BPF_NAME] = { .type = NLA_NUL_STRING,
.len = ACT_BPF_NAME_LEN },
[TCA_ACT_BPF_OPS_LEN] = { .type = NLA_U16 },
[TCA_ACT_BPF_OPS] = { .type = NLA_BINARY,
.len = sizeof(struct sock_filter) * BPF_MAXINSNS },
};
static int tcf_bpf_init_from_ops(struct nlattr **tb, struct tcf_bpf_cfg *cfg)
{
struct sock_filter *bpf_ops;
struct sock_fprog_kern fprog_tmp;
struct bpf_prog *fp;
u16 bpf_size, bpf_num_ops;
int ret;
bpf_num_ops = nla_get_u16(tb[TCA_ACT_BPF_OPS_LEN]);
if (bpf_num_ops > BPF_MAXINSNS || bpf_num_ops == 0)
return -EINVAL;
bpf_size = bpf_num_ops * sizeof(*bpf_ops);
if (bpf_size != nla_len(tb[TCA_ACT_BPF_OPS]))
return -EINVAL;
bpf_ops = kmemdup(nla_data(tb[TCA_ACT_BPF_OPS]), bpf_size, GFP_KERNEL);
if (bpf_ops == NULL)
return -ENOMEM;
fprog_tmp.len = bpf_num_ops;
fprog_tmp.filter = bpf_ops;
ret = bpf_prog_create(&fp, &fprog_tmp);
if (ret < 0) {
kfree(bpf_ops);
return ret;
}
cfg->bpf_ops = bpf_ops;
cfg->bpf_num_ops = bpf_num_ops;
cfg->filter = fp;
act_bpf: fix memory leaks when replacing bpf programs We currently trigger multiple memory leaks when replacing bpf actions, besides others: comm "tc", pid 1909, jiffies 4294851310 (age 1602.796s) hex dump (first 32 bytes): 01 00 00 00 03 00 00 00 00 00 00 00 00 00 00 00 ................ 18 b0 98 6d 00 88 ff ff 00 00 00 00 00 00 00 00 ...m............ backtrace: [<ffffffff817e623e>] kmemleak_alloc+0x4e/0xb0 [<ffffffff8120a22d>] __vmalloc_node_range+0x1bd/0x2c0 [<ffffffff8120a37a>] __vmalloc+0x4a/0x50 [<ffffffff811a8d0a>] bpf_prog_alloc+0x3a/0xa0 [<ffffffff816c0684>] bpf_prog_create+0x44/0xa0 [<ffffffffa09ba4eb>] tcf_bpf_init+0x28b/0x3c0 [act_bpf] [<ffffffff816d7001>] tcf_action_init_1+0x191/0x1b0 [<ffffffff816d70a2>] tcf_action_init+0x82/0xf0 [<ffffffff816d4d12>] tcf_exts_validate+0xb2/0xc0 [<ffffffffa09b5838>] cls_bpf_modify_existing+0x98/0x340 [cls_bpf] [<ffffffffa09b5cd6>] cls_bpf_change+0x1a6/0x274 [cls_bpf] [<ffffffff816d56e5>] tc_ctl_tfilter+0x335/0x910 [<ffffffff816b9145>] rtnetlink_rcv_msg+0x95/0x240 [<ffffffff816df34f>] netlink_rcv_skb+0xaf/0xc0 [<ffffffff816b909e>] rtnetlink_rcv+0x2e/0x40 [<ffffffff816deaaf>] netlink_unicast+0xef/0x1b0 Issue is that the old content from tcf_bpf is allocated and needs to be released when we replace it. We seem to do that since the beginning of act_bpf on the filter and insns, later on the name as well. Example test case, after patch: # FOO="1,6 0 0 4294967295," # BAR="1,6 0 0 4294967294," # tc actions add action bpf bytecode "$FOO" index 2 # tc actions show action bpf action order 0: bpf bytecode '1,6 0 0 4294967295' default-action pipe index 2 ref 1 bind 0 # tc actions replace action bpf bytecode "$BAR" index 2 # tc actions show action bpf action order 0: bpf bytecode '1,6 0 0 4294967294' default-action pipe index 2 ref 1 bind 0 # tc actions replace action bpf bytecode "$FOO" index 2 # tc actions show action bpf action order 0: bpf bytecode '1,6 0 0 4294967295' default-action pipe index 2 ref 1 bind 0 # tc actions del action bpf index 2 [...] # echo "scan" > /sys/kernel/debug/kmemleak # cat /sys/kernel/debug/kmemleak | grep "comm \"tc\"" | wc -l 0 Fixes: d23b8ad8ab23 ("tc: add BPF based action") Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-07-30 00:40:56 +08:00
cfg->is_ebpf = false;
return 0;
}
static int tcf_bpf_init_from_efd(struct nlattr **tb, struct tcf_bpf_cfg *cfg)
{
struct bpf_prog *fp;
char *name = NULL;
u32 bpf_fd;
bpf_fd = nla_get_u32(tb[TCA_ACT_BPF_FD]);
fp = bpf_prog_get_type(bpf_fd, BPF_PROG_TYPE_SCHED_ACT);
if (IS_ERR(fp))
return PTR_ERR(fp);
if (tb[TCA_ACT_BPF_NAME]) {
name = nla_memdup(tb[TCA_ACT_BPF_NAME], GFP_KERNEL);
if (!name) {
bpf_prog_put(fp);
return -ENOMEM;
}
}
cfg->bpf_name = name;
cfg->filter = fp;
act_bpf: fix memory leaks when replacing bpf programs We currently trigger multiple memory leaks when replacing bpf actions, besides others: comm "tc", pid 1909, jiffies 4294851310 (age 1602.796s) hex dump (first 32 bytes): 01 00 00 00 03 00 00 00 00 00 00 00 00 00 00 00 ................ 18 b0 98 6d 00 88 ff ff 00 00 00 00 00 00 00 00 ...m............ backtrace: [<ffffffff817e623e>] kmemleak_alloc+0x4e/0xb0 [<ffffffff8120a22d>] __vmalloc_node_range+0x1bd/0x2c0 [<ffffffff8120a37a>] __vmalloc+0x4a/0x50 [<ffffffff811a8d0a>] bpf_prog_alloc+0x3a/0xa0 [<ffffffff816c0684>] bpf_prog_create+0x44/0xa0 [<ffffffffa09ba4eb>] tcf_bpf_init+0x28b/0x3c0 [act_bpf] [<ffffffff816d7001>] tcf_action_init_1+0x191/0x1b0 [<ffffffff816d70a2>] tcf_action_init+0x82/0xf0 [<ffffffff816d4d12>] tcf_exts_validate+0xb2/0xc0 [<ffffffffa09b5838>] cls_bpf_modify_existing+0x98/0x340 [cls_bpf] [<ffffffffa09b5cd6>] cls_bpf_change+0x1a6/0x274 [cls_bpf] [<ffffffff816d56e5>] tc_ctl_tfilter+0x335/0x910 [<ffffffff816b9145>] rtnetlink_rcv_msg+0x95/0x240 [<ffffffff816df34f>] netlink_rcv_skb+0xaf/0xc0 [<ffffffff816b909e>] rtnetlink_rcv+0x2e/0x40 [<ffffffff816deaaf>] netlink_unicast+0xef/0x1b0 Issue is that the old content from tcf_bpf is allocated and needs to be released when we replace it. We seem to do that since the beginning of act_bpf on the filter and insns, later on the name as well. Example test case, after patch: # FOO="1,6 0 0 4294967295," # BAR="1,6 0 0 4294967294," # tc actions add action bpf bytecode "$FOO" index 2 # tc actions show action bpf action order 0: bpf bytecode '1,6 0 0 4294967295' default-action pipe index 2 ref 1 bind 0 # tc actions replace action bpf bytecode "$BAR" index 2 # tc actions show action bpf action order 0: bpf bytecode '1,6 0 0 4294967294' default-action pipe index 2 ref 1 bind 0 # tc actions replace action bpf bytecode "$FOO" index 2 # tc actions show action bpf action order 0: bpf bytecode '1,6 0 0 4294967295' default-action pipe index 2 ref 1 bind 0 # tc actions del action bpf index 2 [...] # echo "scan" > /sys/kernel/debug/kmemleak # cat /sys/kernel/debug/kmemleak | grep "comm \"tc\"" | wc -l 0 Fixes: d23b8ad8ab23 ("tc: add BPF based action") Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-07-30 00:40:56 +08:00
cfg->is_ebpf = true;
return 0;
}
act_bpf: fix memory leaks when replacing bpf programs We currently trigger multiple memory leaks when replacing bpf actions, besides others: comm "tc", pid 1909, jiffies 4294851310 (age 1602.796s) hex dump (first 32 bytes): 01 00 00 00 03 00 00 00 00 00 00 00 00 00 00 00 ................ 18 b0 98 6d 00 88 ff ff 00 00 00 00 00 00 00 00 ...m............ backtrace: [<ffffffff817e623e>] kmemleak_alloc+0x4e/0xb0 [<ffffffff8120a22d>] __vmalloc_node_range+0x1bd/0x2c0 [<ffffffff8120a37a>] __vmalloc+0x4a/0x50 [<ffffffff811a8d0a>] bpf_prog_alloc+0x3a/0xa0 [<ffffffff816c0684>] bpf_prog_create+0x44/0xa0 [<ffffffffa09ba4eb>] tcf_bpf_init+0x28b/0x3c0 [act_bpf] [<ffffffff816d7001>] tcf_action_init_1+0x191/0x1b0 [<ffffffff816d70a2>] tcf_action_init+0x82/0xf0 [<ffffffff816d4d12>] tcf_exts_validate+0xb2/0xc0 [<ffffffffa09b5838>] cls_bpf_modify_existing+0x98/0x340 [cls_bpf] [<ffffffffa09b5cd6>] cls_bpf_change+0x1a6/0x274 [cls_bpf] [<ffffffff816d56e5>] tc_ctl_tfilter+0x335/0x910 [<ffffffff816b9145>] rtnetlink_rcv_msg+0x95/0x240 [<ffffffff816df34f>] netlink_rcv_skb+0xaf/0xc0 [<ffffffff816b909e>] rtnetlink_rcv+0x2e/0x40 [<ffffffff816deaaf>] netlink_unicast+0xef/0x1b0 Issue is that the old content from tcf_bpf is allocated and needs to be released when we replace it. We seem to do that since the beginning of act_bpf on the filter and insns, later on the name as well. Example test case, after patch: # FOO="1,6 0 0 4294967295," # BAR="1,6 0 0 4294967294," # tc actions add action bpf bytecode "$FOO" index 2 # tc actions show action bpf action order 0: bpf bytecode '1,6 0 0 4294967295' default-action pipe index 2 ref 1 bind 0 # tc actions replace action bpf bytecode "$BAR" index 2 # tc actions show action bpf action order 0: bpf bytecode '1,6 0 0 4294967294' default-action pipe index 2 ref 1 bind 0 # tc actions replace action bpf bytecode "$FOO" index 2 # tc actions show action bpf action order 0: bpf bytecode '1,6 0 0 4294967295' default-action pipe index 2 ref 1 bind 0 # tc actions del action bpf index 2 [...] # echo "scan" > /sys/kernel/debug/kmemleak # cat /sys/kernel/debug/kmemleak | grep "comm \"tc\"" | wc -l 0 Fixes: d23b8ad8ab23 ("tc: add BPF based action") Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-07-30 00:40:56 +08:00
static void tcf_bpf_cfg_cleanup(const struct tcf_bpf_cfg *cfg)
{
net/sched: fix NULL dereference in the error path of tcf_bpf_init() when tcf_bpf_init_from_ops() fails (e.g. because of program having invalid number of instructions), tcf_bpf_cfg_cleanup() calls bpf_prog_put(NULL) or bpf_prog_destroy(NULL). Unless CONFIG_BPF_SYSCALL is unset, this causes the following error: BUG: unable to handle kernel NULL pointer dereference at 0000000000000020 PGD 800000007345a067 P4D 800000007345a067 PUD 340e1067 PMD 0 Oops: 0000 [#1] SMP PTI Modules linked in: act_bpf(E) ip6table_filter ip6_tables iptable_filter binfmt_misc ext4 mbcache jbd2 crct10dif_pclmul crc32_pclmul ghash_clmulni_intel snd_hda_codec_generic pcbc snd_hda_intel snd_hda_codec snd_hda_core snd_hwdep snd_seq snd_seq_device snd_pcm aesni_intel crypto_simd glue_helper cryptd joydev snd_timer snd virtio_balloon pcspkr soundcore i2c_piix4 nfsd auth_rpcgss nfs_acl lockd grace sunrpc ip_tables xfs libcrc32c ata_generic pata_acpi qxl drm_kms_helper syscopyarea sysfillrect sysimgblt fb_sys_fops ttm virtio_blk drm virtio_net virtio_console i2c_core crc32c_intel serio_raw virtio_pci ata_piix libata virtio_ring floppy virtio dm_mirror dm_region_hash dm_log dm_mod [last unloaded: act_bpf] CPU: 3 PID: 5654 Comm: tc Tainted: G E 4.16.0.bpf_test+ #408 Hardware name: Red Hat KVM, BIOS 0.5.1 01/01/2011 RIP: 0010:__bpf_prog_put+0xc/0xc0 RSP: 0018:ffff9594003ef728 EFLAGS: 00010202 RAX: 0000000000000000 RBX: ffff9594003ef758 RCX: 0000000000000024 RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000 RBP: 0000000000000000 R08: 0000000000000001 R09: 0000000000000044 R10: 0000000000000220 R11: ffff8a7ab9f17131 R12: 0000000000000000 R13: ffff8a7ab7c3c8e0 R14: 0000000000000001 R15: ffff8a7ab88f1054 FS: 00007fcb2f17c740(0000) GS:ffff8a7abfd80000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000020 CR3: 000000007c888006 CR4: 00000000001606e0 Call Trace: tcf_bpf_cfg_cleanup+0x2f/0x40 [act_bpf] tcf_bpf_cleanup+0x4c/0x70 [act_bpf] __tcf_idr_release+0x79/0x140 tcf_bpf_init+0x125/0x330 [act_bpf] tcf_action_init_1+0x2cc/0x430 ? get_page_from_freelist+0x3f0/0x11b0 tcf_action_init+0xd3/0x1b0 tc_ctl_action+0x18b/0x240 rtnetlink_rcv_msg+0x29c/0x310 ? _cond_resched+0x15/0x30 ? __kmalloc_node_track_caller+0x1b9/0x270 ? rtnl_calcit.isra.29+0x100/0x100 netlink_rcv_skb+0xd2/0x110 netlink_unicast+0x17c/0x230 netlink_sendmsg+0x2cd/0x3c0 sock_sendmsg+0x30/0x40 ___sys_sendmsg+0x27a/0x290 ? mem_cgroup_commit_charge+0x80/0x130 ? page_add_new_anon_rmap+0x73/0xc0 ? do_anonymous_page+0x2a2/0x560 ? __handle_mm_fault+0xc75/0xe20 __sys_sendmsg+0x58/0xa0 do_syscall_64+0x6e/0x1a0 entry_SYSCALL_64_after_hwframe+0x3d/0xa2 RIP: 0033:0x7fcb2e58eba0 RSP: 002b:00007ffc93c496c8 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007ffc93c497f0 RCX: 00007fcb2e58eba0 RDX: 0000000000000000 RSI: 00007ffc93c49740 RDI: 0000000000000003 RBP: 000000005ac6a646 R08: 0000000000000002 R09: 0000000000000000 R10: 00007ffc93c49120 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffc93c49804 R14: 0000000000000001 R15: 000000000066afa0 Code: 5f 00 48 8b 43 20 48 c7 c7 70 2f 7c b8 c7 40 10 00 00 00 00 5b e9 a5 8b 61 00 0f 1f 44 00 00 0f 1f 44 00 00 41 54 55 48 89 fd 53 <48> 8b 47 20 f0 ff 08 74 05 5b 5d 41 5c c3 41 89 f4 0f 1f 44 00 RIP: __bpf_prog_put+0xc/0xc0 RSP: ffff9594003ef728 CR2: 0000000000000020 Fix it in tcf_bpf_cfg_cleanup(), ensuring that bpf_prog_{put,destroy}(f) is called only when f is not NULL. Fixes: bbc09e7842a5 ("net/sched: fix idr leak on the error path of tcf_bpf_init()") Reported-by: Lucas Bates <lucasb@mojatatu.com> Signed-off-by: Davide Caratti <dcaratti@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-04-06 07:19:37 +08:00
struct bpf_prog *filter = cfg->filter;
if (filter) {
if (cfg->is_ebpf)
bpf_prog_put(filter);
else
bpf_prog_destroy(filter);
}
act_bpf: fix memory leaks when replacing bpf programs We currently trigger multiple memory leaks when replacing bpf actions, besides others: comm "tc", pid 1909, jiffies 4294851310 (age 1602.796s) hex dump (first 32 bytes): 01 00 00 00 03 00 00 00 00 00 00 00 00 00 00 00 ................ 18 b0 98 6d 00 88 ff ff 00 00 00 00 00 00 00 00 ...m............ backtrace: [<ffffffff817e623e>] kmemleak_alloc+0x4e/0xb0 [<ffffffff8120a22d>] __vmalloc_node_range+0x1bd/0x2c0 [<ffffffff8120a37a>] __vmalloc+0x4a/0x50 [<ffffffff811a8d0a>] bpf_prog_alloc+0x3a/0xa0 [<ffffffff816c0684>] bpf_prog_create+0x44/0xa0 [<ffffffffa09ba4eb>] tcf_bpf_init+0x28b/0x3c0 [act_bpf] [<ffffffff816d7001>] tcf_action_init_1+0x191/0x1b0 [<ffffffff816d70a2>] tcf_action_init+0x82/0xf0 [<ffffffff816d4d12>] tcf_exts_validate+0xb2/0xc0 [<ffffffffa09b5838>] cls_bpf_modify_existing+0x98/0x340 [cls_bpf] [<ffffffffa09b5cd6>] cls_bpf_change+0x1a6/0x274 [cls_bpf] [<ffffffff816d56e5>] tc_ctl_tfilter+0x335/0x910 [<ffffffff816b9145>] rtnetlink_rcv_msg+0x95/0x240 [<ffffffff816df34f>] netlink_rcv_skb+0xaf/0xc0 [<ffffffff816b909e>] rtnetlink_rcv+0x2e/0x40 [<ffffffff816deaaf>] netlink_unicast+0xef/0x1b0 Issue is that the old content from tcf_bpf is allocated and needs to be released when we replace it. We seem to do that since the beginning of act_bpf on the filter and insns, later on the name as well. Example test case, after patch: # FOO="1,6 0 0 4294967295," # BAR="1,6 0 0 4294967294," # tc actions add action bpf bytecode "$FOO" index 2 # tc actions show action bpf action order 0: bpf bytecode '1,6 0 0 4294967295' default-action pipe index 2 ref 1 bind 0 # tc actions replace action bpf bytecode "$BAR" index 2 # tc actions show action bpf action order 0: bpf bytecode '1,6 0 0 4294967294' default-action pipe index 2 ref 1 bind 0 # tc actions replace action bpf bytecode "$FOO" index 2 # tc actions show action bpf action order 0: bpf bytecode '1,6 0 0 4294967295' default-action pipe index 2 ref 1 bind 0 # tc actions del action bpf index 2 [...] # echo "scan" > /sys/kernel/debug/kmemleak # cat /sys/kernel/debug/kmemleak | grep "comm \"tc\"" | wc -l 0 Fixes: d23b8ad8ab23 ("tc: add BPF based action") Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-07-30 00:40:56 +08:00
kfree(cfg->bpf_ops);
kfree(cfg->bpf_name);
}
static void tcf_bpf_prog_fill_cfg(const struct tcf_bpf *prog,
struct tcf_bpf_cfg *cfg)
{
cfg->is_ebpf = tcf_bpf_is_ebpf(prog);
/* updates to prog->filter are prevented, since it's called either
* with tcf lock or during final cleanup in rcu callback
*/
cfg->filter = rcu_dereference_protected(prog->filter, 1);
act_bpf: fix memory leaks when replacing bpf programs We currently trigger multiple memory leaks when replacing bpf actions, besides others: comm "tc", pid 1909, jiffies 4294851310 (age 1602.796s) hex dump (first 32 bytes): 01 00 00 00 03 00 00 00 00 00 00 00 00 00 00 00 ................ 18 b0 98 6d 00 88 ff ff 00 00 00 00 00 00 00 00 ...m............ backtrace: [<ffffffff817e623e>] kmemleak_alloc+0x4e/0xb0 [<ffffffff8120a22d>] __vmalloc_node_range+0x1bd/0x2c0 [<ffffffff8120a37a>] __vmalloc+0x4a/0x50 [<ffffffff811a8d0a>] bpf_prog_alloc+0x3a/0xa0 [<ffffffff816c0684>] bpf_prog_create+0x44/0xa0 [<ffffffffa09ba4eb>] tcf_bpf_init+0x28b/0x3c0 [act_bpf] [<ffffffff816d7001>] tcf_action_init_1+0x191/0x1b0 [<ffffffff816d70a2>] tcf_action_init+0x82/0xf0 [<ffffffff816d4d12>] tcf_exts_validate+0xb2/0xc0 [<ffffffffa09b5838>] cls_bpf_modify_existing+0x98/0x340 [cls_bpf] [<ffffffffa09b5cd6>] cls_bpf_change+0x1a6/0x274 [cls_bpf] [<ffffffff816d56e5>] tc_ctl_tfilter+0x335/0x910 [<ffffffff816b9145>] rtnetlink_rcv_msg+0x95/0x240 [<ffffffff816df34f>] netlink_rcv_skb+0xaf/0xc0 [<ffffffff816b909e>] rtnetlink_rcv+0x2e/0x40 [<ffffffff816deaaf>] netlink_unicast+0xef/0x1b0 Issue is that the old content from tcf_bpf is allocated and needs to be released when we replace it. We seem to do that since the beginning of act_bpf on the filter and insns, later on the name as well. Example test case, after patch: # FOO="1,6 0 0 4294967295," # BAR="1,6 0 0 4294967294," # tc actions add action bpf bytecode "$FOO" index 2 # tc actions show action bpf action order 0: bpf bytecode '1,6 0 0 4294967295' default-action pipe index 2 ref 1 bind 0 # tc actions replace action bpf bytecode "$BAR" index 2 # tc actions show action bpf action order 0: bpf bytecode '1,6 0 0 4294967294' default-action pipe index 2 ref 1 bind 0 # tc actions replace action bpf bytecode "$FOO" index 2 # tc actions show action bpf action order 0: bpf bytecode '1,6 0 0 4294967295' default-action pipe index 2 ref 1 bind 0 # tc actions del action bpf index 2 [...] # echo "scan" > /sys/kernel/debug/kmemleak # cat /sys/kernel/debug/kmemleak | grep "comm \"tc\"" | wc -l 0 Fixes: d23b8ad8ab23 ("tc: add BPF based action") Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-07-30 00:40:56 +08:00
cfg->bpf_ops = prog->bpf_ops;
cfg->bpf_name = prog->bpf_name;
}
static int tcf_bpf_init(struct net *net, struct nlattr *nla,
struct nlattr *est, struct tc_action **act,
struct tcf_proto *tp, u32 flags,
struct netlink_ext_ack *extack)
{
struct tc_action_net *tn = net_generic(net, bpf_net_id);
bool bind = flags & TCA_ACT_FLAGS_BIND;
struct nlattr *tb[TCA_ACT_BPF_MAX + 1];
net/sched: act_bpf: validate the control action inside init() the following script: # tc filter add dev crash0 egress matchall \ > action bpf bytecode '1,6 0 0 4294967295' pass index 90 # tc actions replace action bpf \ > bytecode '1,6 0 0 4294967295' goto chain 42 index 90 cookie c1a0c1a0 # tc action show action bpf had the following output: Error: Failed to init TC action chain. We have an error talking to the kernel total acts 1 action order 0: bpf bytecode '1,6 0 0 4294967295' default-action goto chain 42 index 90 ref 2 bind 1 cookie c1a0c1a0 Then, the first packet transmitted by crash0 made the kernel crash: RIP: 0010:tcf_action_exec+0xb8/0x100 Code: 00 00 00 20 74 1d 83 f8 03 75 09 49 83 c4 08 4d 39 ec 75 bc 48 83 c4 10 5b 5d 41 5c 41 5d 41 5e 41 5f c3 49 8b 97 a8 00 00 00 <48> 8b 12 48 89 55 00 48 83 c4 10 5b 5d 41 5c 41 5d 41 5e 41 5f c3 RSP: 0018:ffffb3a0803dfa90 EFLAGS: 00010246 RAX: 000000002000002a RBX: ffff942b347ada00 RCX: 0000000000000000 RDX: 0000000000000000 RSI: ffffb3a08034d038 RDI: ffff942b347ada00 RBP: ffffb3a0803dfb30 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: ffffb3a0803dfb0c R12: ffff942b3b682b00 R13: ffff942b3b682b08 R14: 0000000000000001 R15: ffff942b3b682f00 FS: 00007f6160a72740(0000) GS:ffff942b3da80000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000000 CR3: 00000000795a4002 CR4: 00000000001606e0 Call Trace: tcf_classify+0x58/0x120 __dev_queue_xmit+0x40a/0x890 ? ip_finish_output2+0x16f/0x430 ip_finish_output2+0x16f/0x430 ? ip_output+0x69/0xe0 ip_output+0x69/0xe0 ? ip_forward_options+0x1a0/0x1a0 ip_send_skb+0x15/0x40 raw_sendmsg+0x8e1/0xbd0 ? sched_clock+0x5/0x10 ? sched_clock_cpu+0xc/0xa0 ? try_to_wake_up+0x54/0x480 ? ldsem_down_read+0x3f/0x280 ? _cond_resched+0x15/0x40 ? down_read+0xe/0x30 ? copy_termios+0x1e/0x70 ? tty_mode_ioctl+0x1b6/0x4c0 ? sock_sendmsg+0x36/0x40 sock_sendmsg+0x36/0x40 __sys_sendto+0x10e/0x140 ? do_vfs_ioctl+0xa4/0x640 ? handle_mm_fault+0xdc/0x210 ? syscall_trace_enter+0x1df/0x2e0 ? __audit_syscall_exit+0x216/0x260 __x64_sys_sendto+0x24/0x30 do_syscall_64+0x5b/0x180 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x7f615f7e3c03 Code: 48 8b 0d 90 62 2c 00 f7 d8 64 89 01 48 83 c8 ff c3 66 0f 1f 44 00 00 83 3d 9d c3 2c 00 00 75 13 49 89 ca b8 2c 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 34 c3 48 83 ec 08 e8 4b cc 00 00 48 89 04 24 RSP: 002b:00007ffee5d8cc28 EFLAGS: 00000246 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 000055a4f28f1700 RCX: 00007f615f7e3c03 RDX: 0000000000000040 RSI: 000055a4f28f1700 RDI: 0000000000000003 RBP: 00007ffee5d8e340 R08: 000055a4f28ee510 R09: 0000000000000010 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000040 R13: 000055a4f28f16c0 R14: 000055a4f28ef69c R15: 0000000000000080 Modules linked in: act_bpf veth ip6table_filter ip6_tables iptable_filter binfmt_misc ext4 mbcache crct10dif_pclmul jbd2 crc32_pclmul snd_hda_codec_generic ghash_clmulni_intel snd_hda_intel snd_hda_codec snd_hwdep snd_hda_core snd_seq snd_seq_device snd_pcm aesni_intel crypto_simd cryptd glue_helper pcspkr joydev virtio_balloon snd_timer snd i2c_piix4 soundcore nfsd auth_rpcgss nfs_acl lockd grace sunrpc ip_tables xfs ata_generic pata_acpi qxl drm_kms_helper virtio_blk virtio_net virtio_console net_failover failover syscopyarea sysfillrect sysimgblt fb_sys_fops ttm drm crc32c_intel ata_piix serio_raw libata virtio_pci virtio_ring virtio floppy dm_mirror dm_region_hash dm_log dm_mod CR2: 0000000000000000 Validating the control action within tcf_bpf_init() proved to fix the above issue. A TDC selftest is added to verify the correct behavior. Fixes: db50514f9a9c ("net: sched: add termination action to allow goto chain") Fixes: 97763dc0f401 ("net_sched: reject unknown tcfa_action values") Signed-off-by: Davide Caratti <dcaratti@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-03-20 22:00:00 +08:00
struct tcf_chain *goto_ch = NULL;
act_bpf: fix memory leaks when replacing bpf programs We currently trigger multiple memory leaks when replacing bpf actions, besides others: comm "tc", pid 1909, jiffies 4294851310 (age 1602.796s) hex dump (first 32 bytes): 01 00 00 00 03 00 00 00 00 00 00 00 00 00 00 00 ................ 18 b0 98 6d 00 88 ff ff 00 00 00 00 00 00 00 00 ...m............ backtrace: [<ffffffff817e623e>] kmemleak_alloc+0x4e/0xb0 [<ffffffff8120a22d>] __vmalloc_node_range+0x1bd/0x2c0 [<ffffffff8120a37a>] __vmalloc+0x4a/0x50 [<ffffffff811a8d0a>] bpf_prog_alloc+0x3a/0xa0 [<ffffffff816c0684>] bpf_prog_create+0x44/0xa0 [<ffffffffa09ba4eb>] tcf_bpf_init+0x28b/0x3c0 [act_bpf] [<ffffffff816d7001>] tcf_action_init_1+0x191/0x1b0 [<ffffffff816d70a2>] tcf_action_init+0x82/0xf0 [<ffffffff816d4d12>] tcf_exts_validate+0xb2/0xc0 [<ffffffffa09b5838>] cls_bpf_modify_existing+0x98/0x340 [cls_bpf] [<ffffffffa09b5cd6>] cls_bpf_change+0x1a6/0x274 [cls_bpf] [<ffffffff816d56e5>] tc_ctl_tfilter+0x335/0x910 [<ffffffff816b9145>] rtnetlink_rcv_msg+0x95/0x240 [<ffffffff816df34f>] netlink_rcv_skb+0xaf/0xc0 [<ffffffff816b909e>] rtnetlink_rcv+0x2e/0x40 [<ffffffff816deaaf>] netlink_unicast+0xef/0x1b0 Issue is that the old content from tcf_bpf is allocated and needs to be released when we replace it. We seem to do that since the beginning of act_bpf on the filter and insns, later on the name as well. Example test case, after patch: # FOO="1,6 0 0 4294967295," # BAR="1,6 0 0 4294967294," # tc actions add action bpf bytecode "$FOO" index 2 # tc actions show action bpf action order 0: bpf bytecode '1,6 0 0 4294967295' default-action pipe index 2 ref 1 bind 0 # tc actions replace action bpf bytecode "$BAR" index 2 # tc actions show action bpf action order 0: bpf bytecode '1,6 0 0 4294967294' default-action pipe index 2 ref 1 bind 0 # tc actions replace action bpf bytecode "$FOO" index 2 # tc actions show action bpf action order 0: bpf bytecode '1,6 0 0 4294967295' default-action pipe index 2 ref 1 bind 0 # tc actions del action bpf index 2 [...] # echo "scan" > /sys/kernel/debug/kmemleak # cat /sys/kernel/debug/kmemleak | grep "comm \"tc\"" | wc -l 0 Fixes: d23b8ad8ab23 ("tc: add BPF based action") Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-07-30 00:40:56 +08:00
struct tcf_bpf_cfg cfg, old;
struct tc_act_bpf *parm;
struct tcf_bpf *prog;
bool is_bpf, is_ebpf;
act_bpf: properly support late binding of bpf action to a classifier Since the introduction of the BPF action in d23b8ad8ab23 ("tc: add BPF based action"), late binding was not working as expected. I.e. setting the action part for a classifier only via 'bpf index <num>', where <num> is the index of an existing action, is being rejected by the kernel due to other missing parameters. It doesn't make sense to require these parameters such as BPF opcodes etc, as they are not going to be used anyway: in this case, they're just allocated/parsed and then freed again w/o doing anything meaningful. Instead, parse and verify the remaining parameters *after* the test on tcf_hash_check(), when we really know that we're dealing with creation of a new action or replacement of an existing one and where late binding is thus irrelevant. After patch, test case is now working: FOO="1,6 0 0 4294967295," tc actions add action bpf bytecode "$FOO" tc filter add dev foo parent 1: bpf bytecode "$FOO" flowid 1:1 action bpf index 1 tc actions show action bpf action order 0: bpf bytecode '1,6 0 0 4294967295' default-action pipe index 1 ref 2 bind 1 tc filter show dev foo filter protocol all pref 49152 bpf filter protocol all pref 49152 bpf handle 0x1 flowid 1:1 bytecode '1,6 0 0 4294967295' action order 1: bpf bytecode '1,6 0 0 4294967295' default-action pipe index 1 ref 2 bind 1 Late binding of a BPF action can be useful for preloading maps (e.g. before they hit traffic) in case of eBPF programs, or to share a single eBPF action with multiple classifiers. Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Alexei Starovoitov <ast@plumgrid.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-08-03 22:21:57 +08:00
int ret, res = 0;
u32 index;
if (!nla)
return -EINVAL;
netlink: make validation more configurable for future strictness We currently have two levels of strict validation: 1) liberal (default) - undefined (type >= max) & NLA_UNSPEC attributes accepted - attribute length >= expected accepted - garbage at end of message accepted 2) strict (opt-in) - NLA_UNSPEC attributes accepted - attribute length >= expected accepted Split out parsing strictness into four different options: * TRAILING - check that there's no trailing data after parsing attributes (in message or nested) * MAXTYPE - reject attrs > max known type * UNSPEC - reject attributes with NLA_UNSPEC policy entries * STRICT_ATTRS - strictly validate attribute size The default for future things should be *everything*. The current *_strict() is a combination of TRAILING and MAXTYPE, and is renamed to _deprecated_strict(). The current regular parsing has none of this, and is renamed to *_parse_deprecated(). Additionally it allows us to selectively set one of the new flags even on old policies. Notably, the UNSPEC flag could be useful in this case, since it can be arranged (by filling in the policy) to not be an incompatible userspace ABI change, but would then going forward prevent forgetting attribute entries. Similar can apply to the POLICY flag. We end up with the following renames: * nla_parse -> nla_parse_deprecated * nla_parse_strict -> nla_parse_deprecated_strict * nlmsg_parse -> nlmsg_parse_deprecated * nlmsg_parse_strict -> nlmsg_parse_deprecated_strict * nla_parse_nested -> nla_parse_nested_deprecated * nla_validate_nested -> nla_validate_nested_deprecated Using spatch, of course: @@ expression TB, MAX, HEAD, LEN, POL, EXT; @@ -nla_parse(TB, MAX, HEAD, LEN, POL, EXT) +nla_parse_deprecated(TB, MAX, HEAD, LEN, POL, EXT) @@ expression NLH, HDRLEN, TB, MAX, POL, EXT; @@ -nlmsg_parse(NLH, HDRLEN, TB, MAX, POL, EXT) +nlmsg_parse_deprecated(NLH, HDRLEN, TB, MAX, POL, EXT) @@ expression NLH, HDRLEN, TB, MAX, POL, EXT; @@ -nlmsg_parse_strict(NLH, HDRLEN, TB, MAX, POL, EXT) +nlmsg_parse_deprecated_strict(NLH, HDRLEN, TB, MAX, POL, EXT) @@ expression TB, MAX, NLA, POL, EXT; @@ -nla_parse_nested(TB, MAX, NLA, POL, EXT) +nla_parse_nested_deprecated(TB, MAX, NLA, POL, EXT) @@ expression START, MAX, POL, EXT; @@ -nla_validate_nested(START, MAX, POL, EXT) +nla_validate_nested_deprecated(START, MAX, POL, EXT) @@ expression NLH, HDRLEN, MAX, POL, EXT; @@ -nlmsg_validate(NLH, HDRLEN, MAX, POL, EXT) +nlmsg_validate_deprecated(NLH, HDRLEN, MAX, POL, EXT) For this patch, don't actually add the strict, non-renamed versions yet so that it breaks compile if I get it wrong. Also, while at it, make nla_validate and nla_parse go down to a common __nla_validate_parse() function to avoid code duplication. Ultimately, this allows us to have very strict validation for every new caller of nla_parse()/nlmsg_parse() etc as re-introduced in the next patch, while existing things will continue to work as is. In effect then, this adds fully strict validation for any new command. Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-04-26 20:07:28 +08:00
ret = nla_parse_nested_deprecated(tb, TCA_ACT_BPF_MAX, nla,
act_bpf_policy, NULL);
if (ret < 0)
return ret;
act_bpf: properly support late binding of bpf action to a classifier Since the introduction of the BPF action in d23b8ad8ab23 ("tc: add BPF based action"), late binding was not working as expected. I.e. setting the action part for a classifier only via 'bpf index <num>', where <num> is the index of an existing action, is being rejected by the kernel due to other missing parameters. It doesn't make sense to require these parameters such as BPF opcodes etc, as they are not going to be used anyway: in this case, they're just allocated/parsed and then freed again w/o doing anything meaningful. Instead, parse and verify the remaining parameters *after* the test on tcf_hash_check(), when we really know that we're dealing with creation of a new action or replacement of an existing one and where late binding is thus irrelevant. After patch, test case is now working: FOO="1,6 0 0 4294967295," tc actions add action bpf bytecode "$FOO" tc filter add dev foo parent 1: bpf bytecode "$FOO" flowid 1:1 action bpf index 1 tc actions show action bpf action order 0: bpf bytecode '1,6 0 0 4294967295' default-action pipe index 1 ref 2 bind 1 tc filter show dev foo filter protocol all pref 49152 bpf filter protocol all pref 49152 bpf handle 0x1 flowid 1:1 bytecode '1,6 0 0 4294967295' action order 1: bpf bytecode '1,6 0 0 4294967295' default-action pipe index 1 ref 2 bind 1 Late binding of a BPF action can be useful for preloading maps (e.g. before they hit traffic) in case of eBPF programs, or to share a single eBPF action with multiple classifiers. Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Alexei Starovoitov <ast@plumgrid.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-08-03 22:21:57 +08:00
if (!tb[TCA_ACT_BPF_PARMS])
return -EINVAL;
parm = nla_data(tb[TCA_ACT_BPF_PARMS]);
index = parm->index;
ret = tcf_idr_check_alloc(tn, &index, act, bind);
if (!ret) {
ret = tcf_idr_create(tn, index, est, act,
&act_bpf_ops, bind, true, 0);
if (ret < 0) {
tcf_idr_cleanup(tn, index);
act_bpf: properly support late binding of bpf action to a classifier Since the introduction of the BPF action in d23b8ad8ab23 ("tc: add BPF based action"), late binding was not working as expected. I.e. setting the action part for a classifier only via 'bpf index <num>', where <num> is the index of an existing action, is being rejected by the kernel due to other missing parameters. It doesn't make sense to require these parameters such as BPF opcodes etc, as they are not going to be used anyway: in this case, they're just allocated/parsed and then freed again w/o doing anything meaningful. Instead, parse and verify the remaining parameters *after* the test on tcf_hash_check(), when we really know that we're dealing with creation of a new action or replacement of an existing one and where late binding is thus irrelevant. After patch, test case is now working: FOO="1,6 0 0 4294967295," tc actions add action bpf bytecode "$FOO" tc filter add dev foo parent 1: bpf bytecode "$FOO" flowid 1:1 action bpf index 1 tc actions show action bpf action order 0: bpf bytecode '1,6 0 0 4294967295' default-action pipe index 1 ref 2 bind 1 tc filter show dev foo filter protocol all pref 49152 bpf filter protocol all pref 49152 bpf handle 0x1 flowid 1:1 bytecode '1,6 0 0 4294967295' action order 1: bpf bytecode '1,6 0 0 4294967295' default-action pipe index 1 ref 2 bind 1 Late binding of a BPF action can be useful for preloading maps (e.g. before they hit traffic) in case of eBPF programs, or to share a single eBPF action with multiple classifiers. Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Alexei Starovoitov <ast@plumgrid.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-08-03 22:21:57 +08:00
return ret;
}
act_bpf: properly support late binding of bpf action to a classifier Since the introduction of the BPF action in d23b8ad8ab23 ("tc: add BPF based action"), late binding was not working as expected. I.e. setting the action part for a classifier only via 'bpf index <num>', where <num> is the index of an existing action, is being rejected by the kernel due to other missing parameters. It doesn't make sense to require these parameters such as BPF opcodes etc, as they are not going to be used anyway: in this case, they're just allocated/parsed and then freed again w/o doing anything meaningful. Instead, parse and verify the remaining parameters *after* the test on tcf_hash_check(), when we really know that we're dealing with creation of a new action or replacement of an existing one and where late binding is thus irrelevant. After patch, test case is now working: FOO="1,6 0 0 4294967295," tc actions add action bpf bytecode "$FOO" tc filter add dev foo parent 1: bpf bytecode "$FOO" flowid 1:1 action bpf index 1 tc actions show action bpf action order 0: bpf bytecode '1,6 0 0 4294967295' default-action pipe index 1 ref 2 bind 1 tc filter show dev foo filter protocol all pref 49152 bpf filter protocol all pref 49152 bpf handle 0x1 flowid 1:1 bytecode '1,6 0 0 4294967295' action order 1: bpf bytecode '1,6 0 0 4294967295' default-action pipe index 1 ref 2 bind 1 Late binding of a BPF action can be useful for preloading maps (e.g. before they hit traffic) in case of eBPF programs, or to share a single eBPF action with multiple classifiers. Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Alexei Starovoitov <ast@plumgrid.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-08-03 22:21:57 +08:00
res = ACT_P_CREATED;
} else if (ret > 0) {
/* Don't override defaults. */
if (bind)
act_bpf: properly support late binding of bpf action to a classifier Since the introduction of the BPF action in d23b8ad8ab23 ("tc: add BPF based action"), late binding was not working as expected. I.e. setting the action part for a classifier only via 'bpf index <num>', where <num> is the index of an existing action, is being rejected by the kernel due to other missing parameters. It doesn't make sense to require these parameters such as BPF opcodes etc, as they are not going to be used anyway: in this case, they're just allocated/parsed and then freed again w/o doing anything meaningful. Instead, parse and verify the remaining parameters *after* the test on tcf_hash_check(), when we really know that we're dealing with creation of a new action or replacement of an existing one and where late binding is thus irrelevant. After patch, test case is now working: FOO="1,6 0 0 4294967295," tc actions add action bpf bytecode "$FOO" tc filter add dev foo parent 1: bpf bytecode "$FOO" flowid 1:1 action bpf index 1 tc actions show action bpf action order 0: bpf bytecode '1,6 0 0 4294967295' default-action pipe index 1 ref 2 bind 1 tc filter show dev foo filter protocol all pref 49152 bpf filter protocol all pref 49152 bpf handle 0x1 flowid 1:1 bytecode '1,6 0 0 4294967295' action order 1: bpf bytecode '1,6 0 0 4294967295' default-action pipe index 1 ref 2 bind 1 Late binding of a BPF action can be useful for preloading maps (e.g. before they hit traffic) in case of eBPF programs, or to share a single eBPF action with multiple classifiers. Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Alexei Starovoitov <ast@plumgrid.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-08-03 22:21:57 +08:00
return 0;
if (!(flags & TCA_ACT_FLAGS_REPLACE)) {
tcf_idr_release(*act, bind);
act_bpf: properly support late binding of bpf action to a classifier Since the introduction of the BPF action in d23b8ad8ab23 ("tc: add BPF based action"), late binding was not working as expected. I.e. setting the action part for a classifier only via 'bpf index <num>', where <num> is the index of an existing action, is being rejected by the kernel due to other missing parameters. It doesn't make sense to require these parameters such as BPF opcodes etc, as they are not going to be used anyway: in this case, they're just allocated/parsed and then freed again w/o doing anything meaningful. Instead, parse and verify the remaining parameters *after* the test on tcf_hash_check(), when we really know that we're dealing with creation of a new action or replacement of an existing one and where late binding is thus irrelevant. After patch, test case is now working: FOO="1,6 0 0 4294967295," tc actions add action bpf bytecode "$FOO" tc filter add dev foo parent 1: bpf bytecode "$FOO" flowid 1:1 action bpf index 1 tc actions show action bpf action order 0: bpf bytecode '1,6 0 0 4294967295' default-action pipe index 1 ref 2 bind 1 tc filter show dev foo filter protocol all pref 49152 bpf filter protocol all pref 49152 bpf handle 0x1 flowid 1:1 bytecode '1,6 0 0 4294967295' action order 1: bpf bytecode '1,6 0 0 4294967295' default-action pipe index 1 ref 2 bind 1 Late binding of a BPF action can be useful for preloading maps (e.g. before they hit traffic) in case of eBPF programs, or to share a single eBPF action with multiple classifiers. Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Alexei Starovoitov <ast@plumgrid.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-08-03 22:21:57 +08:00
return -EEXIST;
}
} else {
return ret;
}
net/sched: act_bpf: validate the control action inside init() the following script: # tc filter add dev crash0 egress matchall \ > action bpf bytecode '1,6 0 0 4294967295' pass index 90 # tc actions replace action bpf \ > bytecode '1,6 0 0 4294967295' goto chain 42 index 90 cookie c1a0c1a0 # tc action show action bpf had the following output: Error: Failed to init TC action chain. We have an error talking to the kernel total acts 1 action order 0: bpf bytecode '1,6 0 0 4294967295' default-action goto chain 42 index 90 ref 2 bind 1 cookie c1a0c1a0 Then, the first packet transmitted by crash0 made the kernel crash: RIP: 0010:tcf_action_exec+0xb8/0x100 Code: 00 00 00 20 74 1d 83 f8 03 75 09 49 83 c4 08 4d 39 ec 75 bc 48 83 c4 10 5b 5d 41 5c 41 5d 41 5e 41 5f c3 49 8b 97 a8 00 00 00 <48> 8b 12 48 89 55 00 48 83 c4 10 5b 5d 41 5c 41 5d 41 5e 41 5f c3 RSP: 0018:ffffb3a0803dfa90 EFLAGS: 00010246 RAX: 000000002000002a RBX: ffff942b347ada00 RCX: 0000000000000000 RDX: 0000000000000000 RSI: ffffb3a08034d038 RDI: ffff942b347ada00 RBP: ffffb3a0803dfb30 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: ffffb3a0803dfb0c R12: ffff942b3b682b00 R13: ffff942b3b682b08 R14: 0000000000000001 R15: ffff942b3b682f00 FS: 00007f6160a72740(0000) GS:ffff942b3da80000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000000 CR3: 00000000795a4002 CR4: 00000000001606e0 Call Trace: tcf_classify+0x58/0x120 __dev_queue_xmit+0x40a/0x890 ? ip_finish_output2+0x16f/0x430 ip_finish_output2+0x16f/0x430 ? ip_output+0x69/0xe0 ip_output+0x69/0xe0 ? ip_forward_options+0x1a0/0x1a0 ip_send_skb+0x15/0x40 raw_sendmsg+0x8e1/0xbd0 ? sched_clock+0x5/0x10 ? sched_clock_cpu+0xc/0xa0 ? try_to_wake_up+0x54/0x480 ? ldsem_down_read+0x3f/0x280 ? _cond_resched+0x15/0x40 ? down_read+0xe/0x30 ? copy_termios+0x1e/0x70 ? tty_mode_ioctl+0x1b6/0x4c0 ? sock_sendmsg+0x36/0x40 sock_sendmsg+0x36/0x40 __sys_sendto+0x10e/0x140 ? do_vfs_ioctl+0xa4/0x640 ? handle_mm_fault+0xdc/0x210 ? syscall_trace_enter+0x1df/0x2e0 ? __audit_syscall_exit+0x216/0x260 __x64_sys_sendto+0x24/0x30 do_syscall_64+0x5b/0x180 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x7f615f7e3c03 Code: 48 8b 0d 90 62 2c 00 f7 d8 64 89 01 48 83 c8 ff c3 66 0f 1f 44 00 00 83 3d 9d c3 2c 00 00 75 13 49 89 ca b8 2c 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 34 c3 48 83 ec 08 e8 4b cc 00 00 48 89 04 24 RSP: 002b:00007ffee5d8cc28 EFLAGS: 00000246 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 000055a4f28f1700 RCX: 00007f615f7e3c03 RDX: 0000000000000040 RSI: 000055a4f28f1700 RDI: 0000000000000003 RBP: 00007ffee5d8e340 R08: 000055a4f28ee510 R09: 0000000000000010 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000040 R13: 000055a4f28f16c0 R14: 000055a4f28ef69c R15: 0000000000000080 Modules linked in: act_bpf veth ip6table_filter ip6_tables iptable_filter binfmt_misc ext4 mbcache crct10dif_pclmul jbd2 crc32_pclmul snd_hda_codec_generic ghash_clmulni_intel snd_hda_intel snd_hda_codec snd_hwdep snd_hda_core snd_seq snd_seq_device snd_pcm aesni_intel crypto_simd cryptd glue_helper pcspkr joydev virtio_balloon snd_timer snd i2c_piix4 soundcore nfsd auth_rpcgss nfs_acl lockd grace sunrpc ip_tables xfs ata_generic pata_acpi qxl drm_kms_helper virtio_blk virtio_net virtio_console net_failover failover syscopyarea sysfillrect sysimgblt fb_sys_fops ttm drm crc32c_intel ata_piix serio_raw libata virtio_pci virtio_ring virtio floppy dm_mirror dm_region_hash dm_log dm_mod CR2: 0000000000000000 Validating the control action within tcf_bpf_init() proved to fix the above issue. A TDC selftest is added to verify the correct behavior. Fixes: db50514f9a9c ("net: sched: add termination action to allow goto chain") Fixes: 97763dc0f401 ("net_sched: reject unknown tcfa_action values") Signed-off-by: Davide Caratti <dcaratti@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-03-20 22:00:00 +08:00
ret = tcf_action_check_ctrlact(parm->action, tp, &goto_ch, extack);
if (ret < 0)
goto release_idr;
act_bpf: properly support late binding of bpf action to a classifier Since the introduction of the BPF action in d23b8ad8ab23 ("tc: add BPF based action"), late binding was not working as expected. I.e. setting the action part for a classifier only via 'bpf index <num>', where <num> is the index of an existing action, is being rejected by the kernel due to other missing parameters. It doesn't make sense to require these parameters such as BPF opcodes etc, as they are not going to be used anyway: in this case, they're just allocated/parsed and then freed again w/o doing anything meaningful. Instead, parse and verify the remaining parameters *after* the test on tcf_hash_check(), when we really know that we're dealing with creation of a new action or replacement of an existing one and where late binding is thus irrelevant. After patch, test case is now working: FOO="1,6 0 0 4294967295," tc actions add action bpf bytecode "$FOO" tc filter add dev foo parent 1: bpf bytecode "$FOO" flowid 1:1 action bpf index 1 tc actions show action bpf action order 0: bpf bytecode '1,6 0 0 4294967295' default-action pipe index 1 ref 2 bind 1 tc filter show dev foo filter protocol all pref 49152 bpf filter protocol all pref 49152 bpf handle 0x1 flowid 1:1 bytecode '1,6 0 0 4294967295' action order 1: bpf bytecode '1,6 0 0 4294967295' default-action pipe index 1 ref 2 bind 1 Late binding of a BPF action can be useful for preloading maps (e.g. before they hit traffic) in case of eBPF programs, or to share a single eBPF action with multiple classifiers. Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Alexei Starovoitov <ast@plumgrid.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-08-03 22:21:57 +08:00
is_bpf = tb[TCA_ACT_BPF_OPS_LEN] && tb[TCA_ACT_BPF_OPS];
is_ebpf = tb[TCA_ACT_BPF_FD];
if ((!is_bpf && !is_ebpf) || (is_bpf && is_ebpf)) {
ret = -EINVAL;
net/sched: act_bpf: validate the control action inside init() the following script: # tc filter add dev crash0 egress matchall \ > action bpf bytecode '1,6 0 0 4294967295' pass index 90 # tc actions replace action bpf \ > bytecode '1,6 0 0 4294967295' goto chain 42 index 90 cookie c1a0c1a0 # tc action show action bpf had the following output: Error: Failed to init TC action chain. We have an error talking to the kernel total acts 1 action order 0: bpf bytecode '1,6 0 0 4294967295' default-action goto chain 42 index 90 ref 2 bind 1 cookie c1a0c1a0 Then, the first packet transmitted by crash0 made the kernel crash: RIP: 0010:tcf_action_exec+0xb8/0x100 Code: 00 00 00 20 74 1d 83 f8 03 75 09 49 83 c4 08 4d 39 ec 75 bc 48 83 c4 10 5b 5d 41 5c 41 5d 41 5e 41 5f c3 49 8b 97 a8 00 00 00 <48> 8b 12 48 89 55 00 48 83 c4 10 5b 5d 41 5c 41 5d 41 5e 41 5f c3 RSP: 0018:ffffb3a0803dfa90 EFLAGS: 00010246 RAX: 000000002000002a RBX: ffff942b347ada00 RCX: 0000000000000000 RDX: 0000000000000000 RSI: ffffb3a08034d038 RDI: ffff942b347ada00 RBP: ffffb3a0803dfb30 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: ffffb3a0803dfb0c R12: ffff942b3b682b00 R13: ffff942b3b682b08 R14: 0000000000000001 R15: ffff942b3b682f00 FS: 00007f6160a72740(0000) GS:ffff942b3da80000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000000 CR3: 00000000795a4002 CR4: 00000000001606e0 Call Trace: tcf_classify+0x58/0x120 __dev_queue_xmit+0x40a/0x890 ? ip_finish_output2+0x16f/0x430 ip_finish_output2+0x16f/0x430 ? ip_output+0x69/0xe0 ip_output+0x69/0xe0 ? ip_forward_options+0x1a0/0x1a0 ip_send_skb+0x15/0x40 raw_sendmsg+0x8e1/0xbd0 ? sched_clock+0x5/0x10 ? sched_clock_cpu+0xc/0xa0 ? try_to_wake_up+0x54/0x480 ? ldsem_down_read+0x3f/0x280 ? _cond_resched+0x15/0x40 ? down_read+0xe/0x30 ? copy_termios+0x1e/0x70 ? tty_mode_ioctl+0x1b6/0x4c0 ? sock_sendmsg+0x36/0x40 sock_sendmsg+0x36/0x40 __sys_sendto+0x10e/0x140 ? do_vfs_ioctl+0xa4/0x640 ? handle_mm_fault+0xdc/0x210 ? syscall_trace_enter+0x1df/0x2e0 ? __audit_syscall_exit+0x216/0x260 __x64_sys_sendto+0x24/0x30 do_syscall_64+0x5b/0x180 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x7f615f7e3c03 Code: 48 8b 0d 90 62 2c 00 f7 d8 64 89 01 48 83 c8 ff c3 66 0f 1f 44 00 00 83 3d 9d c3 2c 00 00 75 13 49 89 ca b8 2c 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 34 c3 48 83 ec 08 e8 4b cc 00 00 48 89 04 24 RSP: 002b:00007ffee5d8cc28 EFLAGS: 00000246 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 000055a4f28f1700 RCX: 00007f615f7e3c03 RDX: 0000000000000040 RSI: 000055a4f28f1700 RDI: 0000000000000003 RBP: 00007ffee5d8e340 R08: 000055a4f28ee510 R09: 0000000000000010 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000040 R13: 000055a4f28f16c0 R14: 000055a4f28ef69c R15: 0000000000000080 Modules linked in: act_bpf veth ip6table_filter ip6_tables iptable_filter binfmt_misc ext4 mbcache crct10dif_pclmul jbd2 crc32_pclmul snd_hda_codec_generic ghash_clmulni_intel snd_hda_intel snd_hda_codec snd_hwdep snd_hda_core snd_seq snd_seq_device snd_pcm aesni_intel crypto_simd cryptd glue_helper pcspkr joydev virtio_balloon snd_timer snd i2c_piix4 soundcore nfsd auth_rpcgss nfs_acl lockd grace sunrpc ip_tables xfs ata_generic pata_acpi qxl drm_kms_helper virtio_blk virtio_net virtio_console net_failover failover syscopyarea sysfillrect sysimgblt fb_sys_fops ttm drm crc32c_intel ata_piix serio_raw libata virtio_pci virtio_ring virtio floppy dm_mirror dm_region_hash dm_log dm_mod CR2: 0000000000000000 Validating the control action within tcf_bpf_init() proved to fix the above issue. A TDC selftest is added to verify the correct behavior. Fixes: db50514f9a9c ("net: sched: add termination action to allow goto chain") Fixes: 97763dc0f401 ("net_sched: reject unknown tcfa_action values") Signed-off-by: Davide Caratti <dcaratti@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-03-20 22:00:00 +08:00
goto put_chain;
act_bpf: properly support late binding of bpf action to a classifier Since the introduction of the BPF action in d23b8ad8ab23 ("tc: add BPF based action"), late binding was not working as expected. I.e. setting the action part for a classifier only via 'bpf index <num>', where <num> is the index of an existing action, is being rejected by the kernel due to other missing parameters. It doesn't make sense to require these parameters such as BPF opcodes etc, as they are not going to be used anyway: in this case, they're just allocated/parsed and then freed again w/o doing anything meaningful. Instead, parse and verify the remaining parameters *after* the test on tcf_hash_check(), when we really know that we're dealing with creation of a new action or replacement of an existing one and where late binding is thus irrelevant. After patch, test case is now working: FOO="1,6 0 0 4294967295," tc actions add action bpf bytecode "$FOO" tc filter add dev foo parent 1: bpf bytecode "$FOO" flowid 1:1 action bpf index 1 tc actions show action bpf action order 0: bpf bytecode '1,6 0 0 4294967295' default-action pipe index 1 ref 2 bind 1 tc filter show dev foo filter protocol all pref 49152 bpf filter protocol all pref 49152 bpf handle 0x1 flowid 1:1 bytecode '1,6 0 0 4294967295' action order 1: bpf bytecode '1,6 0 0 4294967295' default-action pipe index 1 ref 2 bind 1 Late binding of a BPF action can be useful for preloading maps (e.g. before they hit traffic) in case of eBPF programs, or to share a single eBPF action with multiple classifiers. Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Alexei Starovoitov <ast@plumgrid.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-08-03 22:21:57 +08:00
}
memset(&cfg, 0, sizeof(cfg));
ret = is_bpf ? tcf_bpf_init_from_ops(tb, &cfg) :
tcf_bpf_init_from_efd(tb, &cfg);
if (ret < 0)
net/sched: act_bpf: validate the control action inside init() the following script: # tc filter add dev crash0 egress matchall \ > action bpf bytecode '1,6 0 0 4294967295' pass index 90 # tc actions replace action bpf \ > bytecode '1,6 0 0 4294967295' goto chain 42 index 90 cookie c1a0c1a0 # tc action show action bpf had the following output: Error: Failed to init TC action chain. We have an error talking to the kernel total acts 1 action order 0: bpf bytecode '1,6 0 0 4294967295' default-action goto chain 42 index 90 ref 2 bind 1 cookie c1a0c1a0 Then, the first packet transmitted by crash0 made the kernel crash: RIP: 0010:tcf_action_exec+0xb8/0x100 Code: 00 00 00 20 74 1d 83 f8 03 75 09 49 83 c4 08 4d 39 ec 75 bc 48 83 c4 10 5b 5d 41 5c 41 5d 41 5e 41 5f c3 49 8b 97 a8 00 00 00 <48> 8b 12 48 89 55 00 48 83 c4 10 5b 5d 41 5c 41 5d 41 5e 41 5f c3 RSP: 0018:ffffb3a0803dfa90 EFLAGS: 00010246 RAX: 000000002000002a RBX: ffff942b347ada00 RCX: 0000000000000000 RDX: 0000000000000000 RSI: ffffb3a08034d038 RDI: ffff942b347ada00 RBP: ffffb3a0803dfb30 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: ffffb3a0803dfb0c R12: ffff942b3b682b00 R13: ffff942b3b682b08 R14: 0000000000000001 R15: ffff942b3b682f00 FS: 00007f6160a72740(0000) GS:ffff942b3da80000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000000 CR3: 00000000795a4002 CR4: 00000000001606e0 Call Trace: tcf_classify+0x58/0x120 __dev_queue_xmit+0x40a/0x890 ? ip_finish_output2+0x16f/0x430 ip_finish_output2+0x16f/0x430 ? ip_output+0x69/0xe0 ip_output+0x69/0xe0 ? ip_forward_options+0x1a0/0x1a0 ip_send_skb+0x15/0x40 raw_sendmsg+0x8e1/0xbd0 ? sched_clock+0x5/0x10 ? sched_clock_cpu+0xc/0xa0 ? try_to_wake_up+0x54/0x480 ? ldsem_down_read+0x3f/0x280 ? _cond_resched+0x15/0x40 ? down_read+0xe/0x30 ? copy_termios+0x1e/0x70 ? tty_mode_ioctl+0x1b6/0x4c0 ? sock_sendmsg+0x36/0x40 sock_sendmsg+0x36/0x40 __sys_sendto+0x10e/0x140 ? do_vfs_ioctl+0xa4/0x640 ? handle_mm_fault+0xdc/0x210 ? syscall_trace_enter+0x1df/0x2e0 ? __audit_syscall_exit+0x216/0x260 __x64_sys_sendto+0x24/0x30 do_syscall_64+0x5b/0x180 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x7f615f7e3c03 Code: 48 8b 0d 90 62 2c 00 f7 d8 64 89 01 48 83 c8 ff c3 66 0f 1f 44 00 00 83 3d 9d c3 2c 00 00 75 13 49 89 ca b8 2c 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 34 c3 48 83 ec 08 e8 4b cc 00 00 48 89 04 24 RSP: 002b:00007ffee5d8cc28 EFLAGS: 00000246 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 000055a4f28f1700 RCX: 00007f615f7e3c03 RDX: 0000000000000040 RSI: 000055a4f28f1700 RDI: 0000000000000003 RBP: 00007ffee5d8e340 R08: 000055a4f28ee510 R09: 0000000000000010 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000040 R13: 000055a4f28f16c0 R14: 000055a4f28ef69c R15: 0000000000000080 Modules linked in: act_bpf veth ip6table_filter ip6_tables iptable_filter binfmt_misc ext4 mbcache crct10dif_pclmul jbd2 crc32_pclmul snd_hda_codec_generic ghash_clmulni_intel snd_hda_intel snd_hda_codec snd_hwdep snd_hda_core snd_seq snd_seq_device snd_pcm aesni_intel crypto_simd cryptd glue_helper pcspkr joydev virtio_balloon snd_timer snd i2c_piix4 soundcore nfsd auth_rpcgss nfs_acl lockd grace sunrpc ip_tables xfs ata_generic pata_acpi qxl drm_kms_helper virtio_blk virtio_net virtio_console net_failover failover syscopyarea sysfillrect sysimgblt fb_sys_fops ttm drm crc32c_intel ata_piix serio_raw libata virtio_pci virtio_ring virtio floppy dm_mirror dm_region_hash dm_log dm_mod CR2: 0000000000000000 Validating the control action within tcf_bpf_init() proved to fix the above issue. A TDC selftest is added to verify the correct behavior. Fixes: db50514f9a9c ("net: sched: add termination action to allow goto chain") Fixes: 97763dc0f401 ("net_sched: reject unknown tcfa_action values") Signed-off-by: Davide Caratti <dcaratti@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-03-20 22:00:00 +08:00
goto put_chain;
act_bpf: properly support late binding of bpf action to a classifier Since the introduction of the BPF action in d23b8ad8ab23 ("tc: add BPF based action"), late binding was not working as expected. I.e. setting the action part for a classifier only via 'bpf index <num>', where <num> is the index of an existing action, is being rejected by the kernel due to other missing parameters. It doesn't make sense to require these parameters such as BPF opcodes etc, as they are not going to be used anyway: in this case, they're just allocated/parsed and then freed again w/o doing anything meaningful. Instead, parse and verify the remaining parameters *after* the test on tcf_hash_check(), when we really know that we're dealing with creation of a new action or replacement of an existing one and where late binding is thus irrelevant. After patch, test case is now working: FOO="1,6 0 0 4294967295," tc actions add action bpf bytecode "$FOO" tc filter add dev foo parent 1: bpf bytecode "$FOO" flowid 1:1 action bpf index 1 tc actions show action bpf action order 0: bpf bytecode '1,6 0 0 4294967295' default-action pipe index 1 ref 2 bind 1 tc filter show dev foo filter protocol all pref 49152 bpf filter protocol all pref 49152 bpf handle 0x1 flowid 1:1 bytecode '1,6 0 0 4294967295' action order 1: bpf bytecode '1,6 0 0 4294967295' default-action pipe index 1 ref 2 bind 1 Late binding of a BPF action can be useful for preloading maps (e.g. before they hit traffic) in case of eBPF programs, or to share a single eBPF action with multiple classifiers. Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Alexei Starovoitov <ast@plumgrid.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-08-03 22:21:57 +08:00
prog = to_bpf(*act);
net: sched: always disable bh when taking tcf_lock Recently, ops->init() and ops->dump() of all actions were modified to always obtain tcf_lock when accessing private action state. Actions that don't depend on tcf_lock for synchronization with their data path use non-bh locking API. However, tcf_lock is also used to protect rate estimator stats in softirq context by timer callback. Change ops->init() and ops->dump() of all actions to disable bh when using tcf_lock to prevent deadlock reported by following lockdep warning: [ 105.470398] ================================ [ 105.475014] WARNING: inconsistent lock state [ 105.479628] 4.18.0-rc8+ #664 Not tainted [ 105.483897] -------------------------------- [ 105.488511] inconsistent {SOFTIRQ-ON-W} -> {IN-SOFTIRQ-W} usage. [ 105.494871] swapper/16/0 [HC0[0]:SC1[1]:HE1:SE0] takes: [ 105.500449] 00000000f86c012e (&(&p->tcfa_lock)->rlock){+.?.}, at: est_fetch_counters+0x3c/0xa0 [ 105.509696] {SOFTIRQ-ON-W} state was registered at: [ 105.514925] _raw_spin_lock+0x2c/0x40 [ 105.519022] tcf_bpf_init+0x579/0x820 [act_bpf] [ 105.523990] tcf_action_init_1+0x4e4/0x660 [ 105.528518] tcf_action_init+0x1ce/0x2d0 [ 105.532880] tcf_exts_validate+0x1d8/0x200 [ 105.537416] fl_change+0x55a/0x268b [cls_flower] [ 105.542469] tc_new_tfilter+0x748/0xa20 [ 105.546738] rtnetlink_rcv_msg+0x56a/0x6d0 [ 105.551268] netlink_rcv_skb+0x18d/0x200 [ 105.555628] netlink_unicast+0x2d0/0x370 [ 105.559990] netlink_sendmsg+0x3b9/0x6a0 [ 105.564349] sock_sendmsg+0x6b/0x80 [ 105.568271] ___sys_sendmsg+0x4a1/0x520 [ 105.572547] __sys_sendmsg+0xd7/0x150 [ 105.576655] do_syscall_64+0x72/0x2c0 [ 105.580757] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 105.586243] irq event stamp: 489296 [ 105.590084] hardirqs last enabled at (489296): [<ffffffffb507e639>] _raw_spin_unlock_irq+0x29/0x40 [ 105.599765] hardirqs last disabled at (489295): [<ffffffffb507e745>] _raw_spin_lock_irq+0x15/0x50 [ 105.609277] softirqs last enabled at (489292): [<ffffffffb413a6a3>] irq_enter+0x83/0xa0 [ 105.618001] softirqs last disabled at (489293): [<ffffffffb413a800>] irq_exit+0x140/0x190 [ 105.626813] other info that might help us debug this: [ 105.633976] Possible unsafe locking scenario: [ 105.640526] CPU0 [ 105.643325] ---- [ 105.646125] lock(&(&p->tcfa_lock)->rlock); [ 105.650747] <Interrupt> [ 105.653717] lock(&(&p->tcfa_lock)->rlock); [ 105.658514] *** DEADLOCK *** [ 105.665349] 1 lock held by swapper/16/0: [ 105.669629] #0: 00000000a640ad99 ((&est->timer)){+.-.}, at: call_timer_fn+0x10b/0x550 [ 105.678200] stack backtrace: [ 105.683194] CPU: 16 PID: 0 Comm: swapper/16 Not tainted 4.18.0-rc8+ #664 [ 105.690249] Hardware name: Supermicro SYS-2028TP-DECR/X10DRT-P, BIOS 2.0b 03/30/2017 [ 105.698626] Call Trace: [ 105.701421] <IRQ> [ 105.703791] dump_stack+0x92/0xeb [ 105.707461] print_usage_bug+0x336/0x34c [ 105.711744] mark_lock+0x7c9/0x980 [ 105.715500] ? print_shortest_lock_dependencies+0x2e0/0x2e0 [ 105.721424] ? check_usage_forwards+0x230/0x230 [ 105.726315] __lock_acquire+0x923/0x26f0 [ 105.730597] ? debug_show_all_locks+0x240/0x240 [ 105.735478] ? mark_lock+0x493/0x980 [ 105.739412] ? check_chain_key+0x140/0x1f0 [ 105.743861] ? __lock_acquire+0x836/0x26f0 [ 105.748323] ? lock_acquire+0x12e/0x290 [ 105.752516] lock_acquire+0x12e/0x290 [ 105.756539] ? est_fetch_counters+0x3c/0xa0 [ 105.761084] _raw_spin_lock+0x2c/0x40 [ 105.765099] ? est_fetch_counters+0x3c/0xa0 [ 105.769633] est_fetch_counters+0x3c/0xa0 [ 105.773995] est_timer+0x87/0x390 [ 105.777670] ? est_fetch_counters+0xa0/0xa0 [ 105.782210] ? lock_acquire+0x12e/0x290 [ 105.786410] call_timer_fn+0x161/0x550 [ 105.790512] ? est_fetch_counters+0xa0/0xa0 [ 105.795055] ? del_timer_sync+0xd0/0xd0 [ 105.799249] ? __lock_is_held+0x93/0x110 [ 105.803531] ? mark_held_locks+0x20/0xe0 [ 105.807813] ? _raw_spin_unlock_irq+0x29/0x40 [ 105.812525] ? est_fetch_counters+0xa0/0xa0 [ 105.817069] ? est_fetch_counters+0xa0/0xa0 [ 105.821610] run_timer_softirq+0x3c4/0x9f0 [ 105.826064] ? lock_acquire+0x12e/0x290 [ 105.830257] ? __bpf_trace_timer_class+0x10/0x10 [ 105.835237] ? __lock_is_held+0x25/0x110 [ 105.839517] __do_softirq+0x11d/0x7bf [ 105.843542] irq_exit+0x140/0x190 [ 105.847208] smp_apic_timer_interrupt+0xac/0x3b0 [ 105.852182] apic_timer_interrupt+0xf/0x20 [ 105.856628] </IRQ> [ 105.859081] RIP: 0010:cpuidle_enter_state+0xd8/0x4d0 [ 105.864395] Code: 46 ff 48 89 44 24 08 0f 1f 44 00 00 31 ff e8 cf ec 46 ff 80 7c 24 07 00 0f 85 1d 02 00 00 e8 9f 90 4b ff fb 66 0f 1f 44 00 00 <4c> 8b 6c 24 08 4d 29 fd 0f 80 36 03 00 00 4c 89 e8 48 ba cf f7 53 [ 105.884288] RSP: 0018:ffff8803ad94fd20 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff13 [ 105.892494] RAX: 0000000000000000 RBX: ffffe8fb300829c0 RCX: ffffffffb41e19e1 [ 105.899988] RDX: 0000000000000007 RSI: dffffc0000000000 RDI: ffff8803ad9358ac [ 105.907503] RBP: ffffffffb6636300 R08: 0000000000000004 R09: 0000000000000000 [ 105.914997] R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000004 [ 105.922487] R13: ffffffffb6636140 R14: ffffffffb66362d8 R15: 000000188d36091b [ 105.929988] ? trace_hardirqs_on_caller+0x141/0x2d0 [ 105.935232] do_idle+0x28e/0x320 [ 105.938817] ? arch_cpu_idle_exit+0x40/0x40 [ 105.943361] ? mark_lock+0x8c1/0x980 [ 105.947295] ? _raw_spin_unlock_irqrestore+0x32/0x60 [ 105.952619] cpu_startup_entry+0xc2/0xd0 [ 105.956900] ? cpu_in_idle+0x20/0x20 [ 105.960830] ? _raw_spin_unlock_irqrestore+0x32/0x60 [ 105.966146] ? trace_hardirqs_on_caller+0x141/0x2d0 [ 105.971391] start_secondary+0x2b5/0x360 [ 105.975669] ? set_cpu_sibling_map+0x1330/0x1330 [ 105.980654] secondary_startup_64+0xa5/0xb0 Taking tcf_lock in sample action with bh disabled causes lockdep to issue a warning regarding possible irq lock inversion dependency between tcf_lock, and psample_groups_lock that is taken when holding tcf_lock in sample init: [ 162.108959] Possible interrupt unsafe locking scenario: [ 162.116386] CPU0 CPU1 [ 162.121277] ---- ---- [ 162.126162] lock(psample_groups_lock); [ 162.130447] local_irq_disable(); [ 162.136772] lock(&(&p->tcfa_lock)->rlock); [ 162.143957] lock(psample_groups_lock); [ 162.150813] <Interrupt> [ 162.153808] lock(&(&p->tcfa_lock)->rlock); [ 162.158608] *** DEADLOCK *** In order to prevent potential lock inversion dependency between tcf_lock and psample_groups_lock, extract call to psample_group_get() from tcf_lock protected section in sample action init function. Fixes: 4e232818bd32 ("net: sched: act_mirred: remove dependency on rtnl lock") Fixes: 764e9a24480f ("net: sched: act_vlan: remove dependency on rtnl lock") Fixes: 729e01260989 ("net: sched: act_tunnel_key: remove dependency on rtnl lock") Fixes: d77284956656 ("net: sched: act_sample: remove dependency on rtnl lock") Fixes: e8917f437006 ("net: sched: act_gact: remove dependency on rtnl lock") Fixes: b6a2b971c0b0 ("net: sched: act_csum: remove dependency on rtnl lock") Fixes: 2142236b4584 ("net: sched: act_bpf: remove dependency on rtnl lock") Signed-off-by: Vlad Buslov <vladbu@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-08-15 02:46:16 +08:00
spin_lock_bh(&prog->tcf_lock);
if (res != ACT_P_CREATED)
act_bpf: fix memory leaks when replacing bpf programs We currently trigger multiple memory leaks when replacing bpf actions, besides others: comm "tc", pid 1909, jiffies 4294851310 (age 1602.796s) hex dump (first 32 bytes): 01 00 00 00 03 00 00 00 00 00 00 00 00 00 00 00 ................ 18 b0 98 6d 00 88 ff ff 00 00 00 00 00 00 00 00 ...m............ backtrace: [<ffffffff817e623e>] kmemleak_alloc+0x4e/0xb0 [<ffffffff8120a22d>] __vmalloc_node_range+0x1bd/0x2c0 [<ffffffff8120a37a>] __vmalloc+0x4a/0x50 [<ffffffff811a8d0a>] bpf_prog_alloc+0x3a/0xa0 [<ffffffff816c0684>] bpf_prog_create+0x44/0xa0 [<ffffffffa09ba4eb>] tcf_bpf_init+0x28b/0x3c0 [act_bpf] [<ffffffff816d7001>] tcf_action_init_1+0x191/0x1b0 [<ffffffff816d70a2>] tcf_action_init+0x82/0xf0 [<ffffffff816d4d12>] tcf_exts_validate+0xb2/0xc0 [<ffffffffa09b5838>] cls_bpf_modify_existing+0x98/0x340 [cls_bpf] [<ffffffffa09b5cd6>] cls_bpf_change+0x1a6/0x274 [cls_bpf] [<ffffffff816d56e5>] tc_ctl_tfilter+0x335/0x910 [<ffffffff816b9145>] rtnetlink_rcv_msg+0x95/0x240 [<ffffffff816df34f>] netlink_rcv_skb+0xaf/0xc0 [<ffffffff816b909e>] rtnetlink_rcv+0x2e/0x40 [<ffffffff816deaaf>] netlink_unicast+0xef/0x1b0 Issue is that the old content from tcf_bpf is allocated and needs to be released when we replace it. We seem to do that since the beginning of act_bpf on the filter and insns, later on the name as well. Example test case, after patch: # FOO="1,6 0 0 4294967295," # BAR="1,6 0 0 4294967294," # tc actions add action bpf bytecode "$FOO" index 2 # tc actions show action bpf action order 0: bpf bytecode '1,6 0 0 4294967295' default-action pipe index 2 ref 1 bind 0 # tc actions replace action bpf bytecode "$BAR" index 2 # tc actions show action bpf action order 0: bpf bytecode '1,6 0 0 4294967294' default-action pipe index 2 ref 1 bind 0 # tc actions replace action bpf bytecode "$FOO" index 2 # tc actions show action bpf action order 0: bpf bytecode '1,6 0 0 4294967295' default-action pipe index 2 ref 1 bind 0 # tc actions del action bpf index 2 [...] # echo "scan" > /sys/kernel/debug/kmemleak # cat /sys/kernel/debug/kmemleak | grep "comm \"tc\"" | wc -l 0 Fixes: d23b8ad8ab23 ("tc: add BPF based action") Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-07-30 00:40:56 +08:00
tcf_bpf_prog_fill_cfg(prog, &old);
prog->bpf_ops = cfg.bpf_ops;
prog->bpf_name = cfg.bpf_name;
if (cfg.bpf_num_ops)
prog->bpf_num_ops = cfg.bpf_num_ops;
net/sched: act_bpf: validate the control action inside init() the following script: # tc filter add dev crash0 egress matchall \ > action bpf bytecode '1,6 0 0 4294967295' pass index 90 # tc actions replace action bpf \ > bytecode '1,6 0 0 4294967295' goto chain 42 index 90 cookie c1a0c1a0 # tc action show action bpf had the following output: Error: Failed to init TC action chain. We have an error talking to the kernel total acts 1 action order 0: bpf bytecode '1,6 0 0 4294967295' default-action goto chain 42 index 90 ref 2 bind 1 cookie c1a0c1a0 Then, the first packet transmitted by crash0 made the kernel crash: RIP: 0010:tcf_action_exec+0xb8/0x100 Code: 00 00 00 20 74 1d 83 f8 03 75 09 49 83 c4 08 4d 39 ec 75 bc 48 83 c4 10 5b 5d 41 5c 41 5d 41 5e 41 5f c3 49 8b 97 a8 00 00 00 <48> 8b 12 48 89 55 00 48 83 c4 10 5b 5d 41 5c 41 5d 41 5e 41 5f c3 RSP: 0018:ffffb3a0803dfa90 EFLAGS: 00010246 RAX: 000000002000002a RBX: ffff942b347ada00 RCX: 0000000000000000 RDX: 0000000000000000 RSI: ffffb3a08034d038 RDI: ffff942b347ada00 RBP: ffffb3a0803dfb30 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: ffffb3a0803dfb0c R12: ffff942b3b682b00 R13: ffff942b3b682b08 R14: 0000000000000001 R15: ffff942b3b682f00 FS: 00007f6160a72740(0000) GS:ffff942b3da80000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000000 CR3: 00000000795a4002 CR4: 00000000001606e0 Call Trace: tcf_classify+0x58/0x120 __dev_queue_xmit+0x40a/0x890 ? ip_finish_output2+0x16f/0x430 ip_finish_output2+0x16f/0x430 ? ip_output+0x69/0xe0 ip_output+0x69/0xe0 ? ip_forward_options+0x1a0/0x1a0 ip_send_skb+0x15/0x40 raw_sendmsg+0x8e1/0xbd0 ? sched_clock+0x5/0x10 ? sched_clock_cpu+0xc/0xa0 ? try_to_wake_up+0x54/0x480 ? ldsem_down_read+0x3f/0x280 ? _cond_resched+0x15/0x40 ? down_read+0xe/0x30 ? copy_termios+0x1e/0x70 ? tty_mode_ioctl+0x1b6/0x4c0 ? sock_sendmsg+0x36/0x40 sock_sendmsg+0x36/0x40 __sys_sendto+0x10e/0x140 ? do_vfs_ioctl+0xa4/0x640 ? handle_mm_fault+0xdc/0x210 ? syscall_trace_enter+0x1df/0x2e0 ? __audit_syscall_exit+0x216/0x260 __x64_sys_sendto+0x24/0x30 do_syscall_64+0x5b/0x180 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x7f615f7e3c03 Code: 48 8b 0d 90 62 2c 00 f7 d8 64 89 01 48 83 c8 ff c3 66 0f 1f 44 00 00 83 3d 9d c3 2c 00 00 75 13 49 89 ca b8 2c 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 34 c3 48 83 ec 08 e8 4b cc 00 00 48 89 04 24 RSP: 002b:00007ffee5d8cc28 EFLAGS: 00000246 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 000055a4f28f1700 RCX: 00007f615f7e3c03 RDX: 0000000000000040 RSI: 000055a4f28f1700 RDI: 0000000000000003 RBP: 00007ffee5d8e340 R08: 000055a4f28ee510 R09: 0000000000000010 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000040 R13: 000055a4f28f16c0 R14: 000055a4f28ef69c R15: 0000000000000080 Modules linked in: act_bpf veth ip6table_filter ip6_tables iptable_filter binfmt_misc ext4 mbcache crct10dif_pclmul jbd2 crc32_pclmul snd_hda_codec_generic ghash_clmulni_intel snd_hda_intel snd_hda_codec snd_hwdep snd_hda_core snd_seq snd_seq_device snd_pcm aesni_intel crypto_simd cryptd glue_helper pcspkr joydev virtio_balloon snd_timer snd i2c_piix4 soundcore nfsd auth_rpcgss nfs_acl lockd grace sunrpc ip_tables xfs ata_generic pata_acpi qxl drm_kms_helper virtio_blk virtio_net virtio_console net_failover failover syscopyarea sysfillrect sysimgblt fb_sys_fops ttm drm crc32c_intel ata_piix serio_raw libata virtio_pci virtio_ring virtio floppy dm_mirror dm_region_hash dm_log dm_mod CR2: 0000000000000000 Validating the control action within tcf_bpf_init() proved to fix the above issue. A TDC selftest is added to verify the correct behavior. Fixes: db50514f9a9c ("net: sched: add termination action to allow goto chain") Fixes: 97763dc0f401 ("net_sched: reject unknown tcfa_action values") Signed-off-by: Davide Caratti <dcaratti@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-03-20 22:00:00 +08:00
goto_ch = tcf_action_set_ctrlact(*act, parm->action, goto_ch);
rcu_assign_pointer(prog->filter, cfg.filter);
net: sched: always disable bh when taking tcf_lock Recently, ops->init() and ops->dump() of all actions were modified to always obtain tcf_lock when accessing private action state. Actions that don't depend on tcf_lock for synchronization with their data path use non-bh locking API. However, tcf_lock is also used to protect rate estimator stats in softirq context by timer callback. Change ops->init() and ops->dump() of all actions to disable bh when using tcf_lock to prevent deadlock reported by following lockdep warning: [ 105.470398] ================================ [ 105.475014] WARNING: inconsistent lock state [ 105.479628] 4.18.0-rc8+ #664 Not tainted [ 105.483897] -------------------------------- [ 105.488511] inconsistent {SOFTIRQ-ON-W} -> {IN-SOFTIRQ-W} usage. [ 105.494871] swapper/16/0 [HC0[0]:SC1[1]:HE1:SE0] takes: [ 105.500449] 00000000f86c012e (&(&p->tcfa_lock)->rlock){+.?.}, at: est_fetch_counters+0x3c/0xa0 [ 105.509696] {SOFTIRQ-ON-W} state was registered at: [ 105.514925] _raw_spin_lock+0x2c/0x40 [ 105.519022] tcf_bpf_init+0x579/0x820 [act_bpf] [ 105.523990] tcf_action_init_1+0x4e4/0x660 [ 105.528518] tcf_action_init+0x1ce/0x2d0 [ 105.532880] tcf_exts_validate+0x1d8/0x200 [ 105.537416] fl_change+0x55a/0x268b [cls_flower] [ 105.542469] tc_new_tfilter+0x748/0xa20 [ 105.546738] rtnetlink_rcv_msg+0x56a/0x6d0 [ 105.551268] netlink_rcv_skb+0x18d/0x200 [ 105.555628] netlink_unicast+0x2d0/0x370 [ 105.559990] netlink_sendmsg+0x3b9/0x6a0 [ 105.564349] sock_sendmsg+0x6b/0x80 [ 105.568271] ___sys_sendmsg+0x4a1/0x520 [ 105.572547] __sys_sendmsg+0xd7/0x150 [ 105.576655] do_syscall_64+0x72/0x2c0 [ 105.580757] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 105.586243] irq event stamp: 489296 [ 105.590084] hardirqs last enabled at (489296): [<ffffffffb507e639>] _raw_spin_unlock_irq+0x29/0x40 [ 105.599765] hardirqs last disabled at (489295): [<ffffffffb507e745>] _raw_spin_lock_irq+0x15/0x50 [ 105.609277] softirqs last enabled at (489292): [<ffffffffb413a6a3>] irq_enter+0x83/0xa0 [ 105.618001] softirqs last disabled at (489293): [<ffffffffb413a800>] irq_exit+0x140/0x190 [ 105.626813] other info that might help us debug this: [ 105.633976] Possible unsafe locking scenario: [ 105.640526] CPU0 [ 105.643325] ---- [ 105.646125] lock(&(&p->tcfa_lock)->rlock); [ 105.650747] <Interrupt> [ 105.653717] lock(&(&p->tcfa_lock)->rlock); [ 105.658514] *** DEADLOCK *** [ 105.665349] 1 lock held by swapper/16/0: [ 105.669629] #0: 00000000a640ad99 ((&est->timer)){+.-.}, at: call_timer_fn+0x10b/0x550 [ 105.678200] stack backtrace: [ 105.683194] CPU: 16 PID: 0 Comm: swapper/16 Not tainted 4.18.0-rc8+ #664 [ 105.690249] Hardware name: Supermicro SYS-2028TP-DECR/X10DRT-P, BIOS 2.0b 03/30/2017 [ 105.698626] Call Trace: [ 105.701421] <IRQ> [ 105.703791] dump_stack+0x92/0xeb [ 105.707461] print_usage_bug+0x336/0x34c [ 105.711744] mark_lock+0x7c9/0x980 [ 105.715500] ? print_shortest_lock_dependencies+0x2e0/0x2e0 [ 105.721424] ? check_usage_forwards+0x230/0x230 [ 105.726315] __lock_acquire+0x923/0x26f0 [ 105.730597] ? debug_show_all_locks+0x240/0x240 [ 105.735478] ? mark_lock+0x493/0x980 [ 105.739412] ? check_chain_key+0x140/0x1f0 [ 105.743861] ? __lock_acquire+0x836/0x26f0 [ 105.748323] ? lock_acquire+0x12e/0x290 [ 105.752516] lock_acquire+0x12e/0x290 [ 105.756539] ? est_fetch_counters+0x3c/0xa0 [ 105.761084] _raw_spin_lock+0x2c/0x40 [ 105.765099] ? est_fetch_counters+0x3c/0xa0 [ 105.769633] est_fetch_counters+0x3c/0xa0 [ 105.773995] est_timer+0x87/0x390 [ 105.777670] ? est_fetch_counters+0xa0/0xa0 [ 105.782210] ? lock_acquire+0x12e/0x290 [ 105.786410] call_timer_fn+0x161/0x550 [ 105.790512] ? est_fetch_counters+0xa0/0xa0 [ 105.795055] ? del_timer_sync+0xd0/0xd0 [ 105.799249] ? __lock_is_held+0x93/0x110 [ 105.803531] ? mark_held_locks+0x20/0xe0 [ 105.807813] ? _raw_spin_unlock_irq+0x29/0x40 [ 105.812525] ? est_fetch_counters+0xa0/0xa0 [ 105.817069] ? est_fetch_counters+0xa0/0xa0 [ 105.821610] run_timer_softirq+0x3c4/0x9f0 [ 105.826064] ? lock_acquire+0x12e/0x290 [ 105.830257] ? __bpf_trace_timer_class+0x10/0x10 [ 105.835237] ? __lock_is_held+0x25/0x110 [ 105.839517] __do_softirq+0x11d/0x7bf [ 105.843542] irq_exit+0x140/0x190 [ 105.847208] smp_apic_timer_interrupt+0xac/0x3b0 [ 105.852182] apic_timer_interrupt+0xf/0x20 [ 105.856628] </IRQ> [ 105.859081] RIP: 0010:cpuidle_enter_state+0xd8/0x4d0 [ 105.864395] Code: 46 ff 48 89 44 24 08 0f 1f 44 00 00 31 ff e8 cf ec 46 ff 80 7c 24 07 00 0f 85 1d 02 00 00 e8 9f 90 4b ff fb 66 0f 1f 44 00 00 <4c> 8b 6c 24 08 4d 29 fd 0f 80 36 03 00 00 4c 89 e8 48 ba cf f7 53 [ 105.884288] RSP: 0018:ffff8803ad94fd20 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff13 [ 105.892494] RAX: 0000000000000000 RBX: ffffe8fb300829c0 RCX: ffffffffb41e19e1 [ 105.899988] RDX: 0000000000000007 RSI: dffffc0000000000 RDI: ffff8803ad9358ac [ 105.907503] RBP: ffffffffb6636300 R08: 0000000000000004 R09: 0000000000000000 [ 105.914997] R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000004 [ 105.922487] R13: ffffffffb6636140 R14: ffffffffb66362d8 R15: 000000188d36091b [ 105.929988] ? trace_hardirqs_on_caller+0x141/0x2d0 [ 105.935232] do_idle+0x28e/0x320 [ 105.938817] ? arch_cpu_idle_exit+0x40/0x40 [ 105.943361] ? mark_lock+0x8c1/0x980 [ 105.947295] ? _raw_spin_unlock_irqrestore+0x32/0x60 [ 105.952619] cpu_startup_entry+0xc2/0xd0 [ 105.956900] ? cpu_in_idle+0x20/0x20 [ 105.960830] ? _raw_spin_unlock_irqrestore+0x32/0x60 [ 105.966146] ? trace_hardirqs_on_caller+0x141/0x2d0 [ 105.971391] start_secondary+0x2b5/0x360 [ 105.975669] ? set_cpu_sibling_map+0x1330/0x1330 [ 105.980654] secondary_startup_64+0xa5/0xb0 Taking tcf_lock in sample action with bh disabled causes lockdep to issue a warning regarding possible irq lock inversion dependency between tcf_lock, and psample_groups_lock that is taken when holding tcf_lock in sample init: [ 162.108959] Possible interrupt unsafe locking scenario: [ 162.116386] CPU0 CPU1 [ 162.121277] ---- ---- [ 162.126162] lock(psample_groups_lock); [ 162.130447] local_irq_disable(); [ 162.136772] lock(&(&p->tcfa_lock)->rlock); [ 162.143957] lock(psample_groups_lock); [ 162.150813] <Interrupt> [ 162.153808] lock(&(&p->tcfa_lock)->rlock); [ 162.158608] *** DEADLOCK *** In order to prevent potential lock inversion dependency between tcf_lock and psample_groups_lock, extract call to psample_group_get() from tcf_lock protected section in sample action init function. Fixes: 4e232818bd32 ("net: sched: act_mirred: remove dependency on rtnl lock") Fixes: 764e9a24480f ("net: sched: act_vlan: remove dependency on rtnl lock") Fixes: 729e01260989 ("net: sched: act_tunnel_key: remove dependency on rtnl lock") Fixes: d77284956656 ("net: sched: act_sample: remove dependency on rtnl lock") Fixes: e8917f437006 ("net: sched: act_gact: remove dependency on rtnl lock") Fixes: b6a2b971c0b0 ("net: sched: act_csum: remove dependency on rtnl lock") Fixes: 2142236b4584 ("net: sched: act_bpf: remove dependency on rtnl lock") Signed-off-by: Vlad Buslov <vladbu@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-08-15 02:46:16 +08:00
spin_unlock_bh(&prog->tcf_lock);
net/sched: act_bpf: validate the control action inside init() the following script: # tc filter add dev crash0 egress matchall \ > action bpf bytecode '1,6 0 0 4294967295' pass index 90 # tc actions replace action bpf \ > bytecode '1,6 0 0 4294967295' goto chain 42 index 90 cookie c1a0c1a0 # tc action show action bpf had the following output: Error: Failed to init TC action chain. We have an error talking to the kernel total acts 1 action order 0: bpf bytecode '1,6 0 0 4294967295' default-action goto chain 42 index 90 ref 2 bind 1 cookie c1a0c1a0 Then, the first packet transmitted by crash0 made the kernel crash: RIP: 0010:tcf_action_exec+0xb8/0x100 Code: 00 00 00 20 74 1d 83 f8 03 75 09 49 83 c4 08 4d 39 ec 75 bc 48 83 c4 10 5b 5d 41 5c 41 5d 41 5e 41 5f c3 49 8b 97 a8 00 00 00 <48> 8b 12 48 89 55 00 48 83 c4 10 5b 5d 41 5c 41 5d 41 5e 41 5f c3 RSP: 0018:ffffb3a0803dfa90 EFLAGS: 00010246 RAX: 000000002000002a RBX: ffff942b347ada00 RCX: 0000000000000000 RDX: 0000000000000000 RSI: ffffb3a08034d038 RDI: ffff942b347ada00 RBP: ffffb3a0803dfb30 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: ffffb3a0803dfb0c R12: ffff942b3b682b00 R13: ffff942b3b682b08 R14: 0000000000000001 R15: ffff942b3b682f00 FS: 00007f6160a72740(0000) GS:ffff942b3da80000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000000 CR3: 00000000795a4002 CR4: 00000000001606e0 Call Trace: tcf_classify+0x58/0x120 __dev_queue_xmit+0x40a/0x890 ? ip_finish_output2+0x16f/0x430 ip_finish_output2+0x16f/0x430 ? ip_output+0x69/0xe0 ip_output+0x69/0xe0 ? ip_forward_options+0x1a0/0x1a0 ip_send_skb+0x15/0x40 raw_sendmsg+0x8e1/0xbd0 ? sched_clock+0x5/0x10 ? sched_clock_cpu+0xc/0xa0 ? try_to_wake_up+0x54/0x480 ? ldsem_down_read+0x3f/0x280 ? _cond_resched+0x15/0x40 ? down_read+0xe/0x30 ? copy_termios+0x1e/0x70 ? tty_mode_ioctl+0x1b6/0x4c0 ? sock_sendmsg+0x36/0x40 sock_sendmsg+0x36/0x40 __sys_sendto+0x10e/0x140 ? do_vfs_ioctl+0xa4/0x640 ? handle_mm_fault+0xdc/0x210 ? syscall_trace_enter+0x1df/0x2e0 ? __audit_syscall_exit+0x216/0x260 __x64_sys_sendto+0x24/0x30 do_syscall_64+0x5b/0x180 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x7f615f7e3c03 Code: 48 8b 0d 90 62 2c 00 f7 d8 64 89 01 48 83 c8 ff c3 66 0f 1f 44 00 00 83 3d 9d c3 2c 00 00 75 13 49 89 ca b8 2c 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 34 c3 48 83 ec 08 e8 4b cc 00 00 48 89 04 24 RSP: 002b:00007ffee5d8cc28 EFLAGS: 00000246 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 000055a4f28f1700 RCX: 00007f615f7e3c03 RDX: 0000000000000040 RSI: 000055a4f28f1700 RDI: 0000000000000003 RBP: 00007ffee5d8e340 R08: 000055a4f28ee510 R09: 0000000000000010 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000040 R13: 000055a4f28f16c0 R14: 000055a4f28ef69c R15: 0000000000000080 Modules linked in: act_bpf veth ip6table_filter ip6_tables iptable_filter binfmt_misc ext4 mbcache crct10dif_pclmul jbd2 crc32_pclmul snd_hda_codec_generic ghash_clmulni_intel snd_hda_intel snd_hda_codec snd_hwdep snd_hda_core snd_seq snd_seq_device snd_pcm aesni_intel crypto_simd cryptd glue_helper pcspkr joydev virtio_balloon snd_timer snd i2c_piix4 soundcore nfsd auth_rpcgss nfs_acl lockd grace sunrpc ip_tables xfs ata_generic pata_acpi qxl drm_kms_helper virtio_blk virtio_net virtio_console net_failover failover syscopyarea sysfillrect sysimgblt fb_sys_fops ttm drm crc32c_intel ata_piix serio_raw libata virtio_pci virtio_ring virtio floppy dm_mirror dm_region_hash dm_log dm_mod CR2: 0000000000000000 Validating the control action within tcf_bpf_init() proved to fix the above issue. A TDC selftest is added to verify the correct behavior. Fixes: db50514f9a9c ("net: sched: add termination action to allow goto chain") Fixes: 97763dc0f401 ("net_sched: reject unknown tcfa_action values") Signed-off-by: Davide Caratti <dcaratti@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-03-20 22:00:00 +08:00
if (goto_ch)
tcf_chain_put_by_act(goto_ch);
if (res != ACT_P_CREATED) {
/* make sure the program being replaced is no longer executing */
synchronize_rcu();
act_bpf: fix memory leaks when replacing bpf programs We currently trigger multiple memory leaks when replacing bpf actions, besides others: comm "tc", pid 1909, jiffies 4294851310 (age 1602.796s) hex dump (first 32 bytes): 01 00 00 00 03 00 00 00 00 00 00 00 00 00 00 00 ................ 18 b0 98 6d 00 88 ff ff 00 00 00 00 00 00 00 00 ...m............ backtrace: [<ffffffff817e623e>] kmemleak_alloc+0x4e/0xb0 [<ffffffff8120a22d>] __vmalloc_node_range+0x1bd/0x2c0 [<ffffffff8120a37a>] __vmalloc+0x4a/0x50 [<ffffffff811a8d0a>] bpf_prog_alloc+0x3a/0xa0 [<ffffffff816c0684>] bpf_prog_create+0x44/0xa0 [<ffffffffa09ba4eb>] tcf_bpf_init+0x28b/0x3c0 [act_bpf] [<ffffffff816d7001>] tcf_action_init_1+0x191/0x1b0 [<ffffffff816d70a2>] tcf_action_init+0x82/0xf0 [<ffffffff816d4d12>] tcf_exts_validate+0xb2/0xc0 [<ffffffffa09b5838>] cls_bpf_modify_existing+0x98/0x340 [cls_bpf] [<ffffffffa09b5cd6>] cls_bpf_change+0x1a6/0x274 [cls_bpf] [<ffffffff816d56e5>] tc_ctl_tfilter+0x335/0x910 [<ffffffff816b9145>] rtnetlink_rcv_msg+0x95/0x240 [<ffffffff816df34f>] netlink_rcv_skb+0xaf/0xc0 [<ffffffff816b909e>] rtnetlink_rcv+0x2e/0x40 [<ffffffff816deaaf>] netlink_unicast+0xef/0x1b0 Issue is that the old content from tcf_bpf is allocated and needs to be released when we replace it. We seem to do that since the beginning of act_bpf on the filter and insns, later on the name as well. Example test case, after patch: # FOO="1,6 0 0 4294967295," # BAR="1,6 0 0 4294967294," # tc actions add action bpf bytecode "$FOO" index 2 # tc actions show action bpf action order 0: bpf bytecode '1,6 0 0 4294967295' default-action pipe index 2 ref 1 bind 0 # tc actions replace action bpf bytecode "$BAR" index 2 # tc actions show action bpf action order 0: bpf bytecode '1,6 0 0 4294967294' default-action pipe index 2 ref 1 bind 0 # tc actions replace action bpf bytecode "$FOO" index 2 # tc actions show action bpf action order 0: bpf bytecode '1,6 0 0 4294967295' default-action pipe index 2 ref 1 bind 0 # tc actions del action bpf index 2 [...] # echo "scan" > /sys/kernel/debug/kmemleak # cat /sys/kernel/debug/kmemleak | grep "comm \"tc\"" | wc -l 0 Fixes: d23b8ad8ab23 ("tc: add BPF based action") Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-07-30 00:40:56 +08:00
tcf_bpf_cfg_cleanup(&old);
}
act_bpf: properly support late binding of bpf action to a classifier Since the introduction of the BPF action in d23b8ad8ab23 ("tc: add BPF based action"), late binding was not working as expected. I.e. setting the action part for a classifier only via 'bpf index <num>', where <num> is the index of an existing action, is being rejected by the kernel due to other missing parameters. It doesn't make sense to require these parameters such as BPF opcodes etc, as they are not going to be used anyway: in this case, they're just allocated/parsed and then freed again w/o doing anything meaningful. Instead, parse and verify the remaining parameters *after* the test on tcf_hash_check(), when we really know that we're dealing with creation of a new action or replacement of an existing one and where late binding is thus irrelevant. After patch, test case is now working: FOO="1,6 0 0 4294967295," tc actions add action bpf bytecode "$FOO" tc filter add dev foo parent 1: bpf bytecode "$FOO" flowid 1:1 action bpf index 1 tc actions show action bpf action order 0: bpf bytecode '1,6 0 0 4294967295' default-action pipe index 1 ref 2 bind 1 tc filter show dev foo filter protocol all pref 49152 bpf filter protocol all pref 49152 bpf handle 0x1 flowid 1:1 bytecode '1,6 0 0 4294967295' action order 1: bpf bytecode '1,6 0 0 4294967295' default-action pipe index 1 ref 2 bind 1 Late binding of a BPF action can be useful for preloading maps (e.g. before they hit traffic) in case of eBPF programs, or to share a single eBPF action with multiple classifiers. Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Alexei Starovoitov <ast@plumgrid.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-08-03 22:21:57 +08:00
return res;
net/sched: act_bpf: validate the control action inside init() the following script: # tc filter add dev crash0 egress matchall \ > action bpf bytecode '1,6 0 0 4294967295' pass index 90 # tc actions replace action bpf \ > bytecode '1,6 0 0 4294967295' goto chain 42 index 90 cookie c1a0c1a0 # tc action show action bpf had the following output: Error: Failed to init TC action chain. We have an error talking to the kernel total acts 1 action order 0: bpf bytecode '1,6 0 0 4294967295' default-action goto chain 42 index 90 ref 2 bind 1 cookie c1a0c1a0 Then, the first packet transmitted by crash0 made the kernel crash: RIP: 0010:tcf_action_exec+0xb8/0x100 Code: 00 00 00 20 74 1d 83 f8 03 75 09 49 83 c4 08 4d 39 ec 75 bc 48 83 c4 10 5b 5d 41 5c 41 5d 41 5e 41 5f c3 49 8b 97 a8 00 00 00 <48> 8b 12 48 89 55 00 48 83 c4 10 5b 5d 41 5c 41 5d 41 5e 41 5f c3 RSP: 0018:ffffb3a0803dfa90 EFLAGS: 00010246 RAX: 000000002000002a RBX: ffff942b347ada00 RCX: 0000000000000000 RDX: 0000000000000000 RSI: ffffb3a08034d038 RDI: ffff942b347ada00 RBP: ffffb3a0803dfb30 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: ffffb3a0803dfb0c R12: ffff942b3b682b00 R13: ffff942b3b682b08 R14: 0000000000000001 R15: ffff942b3b682f00 FS: 00007f6160a72740(0000) GS:ffff942b3da80000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000000 CR3: 00000000795a4002 CR4: 00000000001606e0 Call Trace: tcf_classify+0x58/0x120 __dev_queue_xmit+0x40a/0x890 ? ip_finish_output2+0x16f/0x430 ip_finish_output2+0x16f/0x430 ? ip_output+0x69/0xe0 ip_output+0x69/0xe0 ? ip_forward_options+0x1a0/0x1a0 ip_send_skb+0x15/0x40 raw_sendmsg+0x8e1/0xbd0 ? sched_clock+0x5/0x10 ? sched_clock_cpu+0xc/0xa0 ? try_to_wake_up+0x54/0x480 ? ldsem_down_read+0x3f/0x280 ? _cond_resched+0x15/0x40 ? down_read+0xe/0x30 ? copy_termios+0x1e/0x70 ? tty_mode_ioctl+0x1b6/0x4c0 ? sock_sendmsg+0x36/0x40 sock_sendmsg+0x36/0x40 __sys_sendto+0x10e/0x140 ? do_vfs_ioctl+0xa4/0x640 ? handle_mm_fault+0xdc/0x210 ? syscall_trace_enter+0x1df/0x2e0 ? __audit_syscall_exit+0x216/0x260 __x64_sys_sendto+0x24/0x30 do_syscall_64+0x5b/0x180 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x7f615f7e3c03 Code: 48 8b 0d 90 62 2c 00 f7 d8 64 89 01 48 83 c8 ff c3 66 0f 1f 44 00 00 83 3d 9d c3 2c 00 00 75 13 49 89 ca b8 2c 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 34 c3 48 83 ec 08 e8 4b cc 00 00 48 89 04 24 RSP: 002b:00007ffee5d8cc28 EFLAGS: 00000246 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 000055a4f28f1700 RCX: 00007f615f7e3c03 RDX: 0000000000000040 RSI: 000055a4f28f1700 RDI: 0000000000000003 RBP: 00007ffee5d8e340 R08: 000055a4f28ee510 R09: 0000000000000010 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000040 R13: 000055a4f28f16c0 R14: 000055a4f28ef69c R15: 0000000000000080 Modules linked in: act_bpf veth ip6table_filter ip6_tables iptable_filter binfmt_misc ext4 mbcache crct10dif_pclmul jbd2 crc32_pclmul snd_hda_codec_generic ghash_clmulni_intel snd_hda_intel snd_hda_codec snd_hwdep snd_hda_core snd_seq snd_seq_device snd_pcm aesni_intel crypto_simd cryptd glue_helper pcspkr joydev virtio_balloon snd_timer snd i2c_piix4 soundcore nfsd auth_rpcgss nfs_acl lockd grace sunrpc ip_tables xfs ata_generic pata_acpi qxl drm_kms_helper virtio_blk virtio_net virtio_console net_failover failover syscopyarea sysfillrect sysimgblt fb_sys_fops ttm drm crc32c_intel ata_piix serio_raw libata virtio_pci virtio_ring virtio floppy dm_mirror dm_region_hash dm_log dm_mod CR2: 0000000000000000 Validating the control action within tcf_bpf_init() proved to fix the above issue. A TDC selftest is added to verify the correct behavior. Fixes: db50514f9a9c ("net: sched: add termination action to allow goto chain") Fixes: 97763dc0f401 ("net_sched: reject unknown tcfa_action values") Signed-off-by: Davide Caratti <dcaratti@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-03-20 22:00:00 +08:00
put_chain:
if (goto_ch)
tcf_chain_put_by_act(goto_ch);
release_idr:
tcf_idr_release(*act, bind);
return ret;
}
static void tcf_bpf_cleanup(struct tc_action *act)
{
act_bpf: fix memory leaks when replacing bpf programs We currently trigger multiple memory leaks when replacing bpf actions, besides others: comm "tc", pid 1909, jiffies 4294851310 (age 1602.796s) hex dump (first 32 bytes): 01 00 00 00 03 00 00 00 00 00 00 00 00 00 00 00 ................ 18 b0 98 6d 00 88 ff ff 00 00 00 00 00 00 00 00 ...m............ backtrace: [<ffffffff817e623e>] kmemleak_alloc+0x4e/0xb0 [<ffffffff8120a22d>] __vmalloc_node_range+0x1bd/0x2c0 [<ffffffff8120a37a>] __vmalloc+0x4a/0x50 [<ffffffff811a8d0a>] bpf_prog_alloc+0x3a/0xa0 [<ffffffff816c0684>] bpf_prog_create+0x44/0xa0 [<ffffffffa09ba4eb>] tcf_bpf_init+0x28b/0x3c0 [act_bpf] [<ffffffff816d7001>] tcf_action_init_1+0x191/0x1b0 [<ffffffff816d70a2>] tcf_action_init+0x82/0xf0 [<ffffffff816d4d12>] tcf_exts_validate+0xb2/0xc0 [<ffffffffa09b5838>] cls_bpf_modify_existing+0x98/0x340 [cls_bpf] [<ffffffffa09b5cd6>] cls_bpf_change+0x1a6/0x274 [cls_bpf] [<ffffffff816d56e5>] tc_ctl_tfilter+0x335/0x910 [<ffffffff816b9145>] rtnetlink_rcv_msg+0x95/0x240 [<ffffffff816df34f>] netlink_rcv_skb+0xaf/0xc0 [<ffffffff816b909e>] rtnetlink_rcv+0x2e/0x40 [<ffffffff816deaaf>] netlink_unicast+0xef/0x1b0 Issue is that the old content from tcf_bpf is allocated and needs to be released when we replace it. We seem to do that since the beginning of act_bpf on the filter and insns, later on the name as well. Example test case, after patch: # FOO="1,6 0 0 4294967295," # BAR="1,6 0 0 4294967294," # tc actions add action bpf bytecode "$FOO" index 2 # tc actions show action bpf action order 0: bpf bytecode '1,6 0 0 4294967295' default-action pipe index 2 ref 1 bind 0 # tc actions replace action bpf bytecode "$BAR" index 2 # tc actions show action bpf action order 0: bpf bytecode '1,6 0 0 4294967294' default-action pipe index 2 ref 1 bind 0 # tc actions replace action bpf bytecode "$FOO" index 2 # tc actions show action bpf action order 0: bpf bytecode '1,6 0 0 4294967295' default-action pipe index 2 ref 1 bind 0 # tc actions del action bpf index 2 [...] # echo "scan" > /sys/kernel/debug/kmemleak # cat /sys/kernel/debug/kmemleak | grep "comm \"tc\"" | wc -l 0 Fixes: d23b8ad8ab23 ("tc: add BPF based action") Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-07-30 00:40:56 +08:00
struct tcf_bpf_cfg tmp;
tcf_bpf_prog_fill_cfg(to_bpf(act), &tmp);
act_bpf: fix memory leaks when replacing bpf programs We currently trigger multiple memory leaks when replacing bpf actions, besides others: comm "tc", pid 1909, jiffies 4294851310 (age 1602.796s) hex dump (first 32 bytes): 01 00 00 00 03 00 00 00 00 00 00 00 00 00 00 00 ................ 18 b0 98 6d 00 88 ff ff 00 00 00 00 00 00 00 00 ...m............ backtrace: [<ffffffff817e623e>] kmemleak_alloc+0x4e/0xb0 [<ffffffff8120a22d>] __vmalloc_node_range+0x1bd/0x2c0 [<ffffffff8120a37a>] __vmalloc+0x4a/0x50 [<ffffffff811a8d0a>] bpf_prog_alloc+0x3a/0xa0 [<ffffffff816c0684>] bpf_prog_create+0x44/0xa0 [<ffffffffa09ba4eb>] tcf_bpf_init+0x28b/0x3c0 [act_bpf] [<ffffffff816d7001>] tcf_action_init_1+0x191/0x1b0 [<ffffffff816d70a2>] tcf_action_init+0x82/0xf0 [<ffffffff816d4d12>] tcf_exts_validate+0xb2/0xc0 [<ffffffffa09b5838>] cls_bpf_modify_existing+0x98/0x340 [cls_bpf] [<ffffffffa09b5cd6>] cls_bpf_change+0x1a6/0x274 [cls_bpf] [<ffffffff816d56e5>] tc_ctl_tfilter+0x335/0x910 [<ffffffff816b9145>] rtnetlink_rcv_msg+0x95/0x240 [<ffffffff816df34f>] netlink_rcv_skb+0xaf/0xc0 [<ffffffff816b909e>] rtnetlink_rcv+0x2e/0x40 [<ffffffff816deaaf>] netlink_unicast+0xef/0x1b0 Issue is that the old content from tcf_bpf is allocated and needs to be released when we replace it. We seem to do that since the beginning of act_bpf on the filter and insns, later on the name as well. Example test case, after patch: # FOO="1,6 0 0 4294967295," # BAR="1,6 0 0 4294967294," # tc actions add action bpf bytecode "$FOO" index 2 # tc actions show action bpf action order 0: bpf bytecode '1,6 0 0 4294967295' default-action pipe index 2 ref 1 bind 0 # tc actions replace action bpf bytecode "$BAR" index 2 # tc actions show action bpf action order 0: bpf bytecode '1,6 0 0 4294967294' default-action pipe index 2 ref 1 bind 0 # tc actions replace action bpf bytecode "$FOO" index 2 # tc actions show action bpf action order 0: bpf bytecode '1,6 0 0 4294967295' default-action pipe index 2 ref 1 bind 0 # tc actions del action bpf index 2 [...] # echo "scan" > /sys/kernel/debug/kmemleak # cat /sys/kernel/debug/kmemleak | grep "comm \"tc\"" | wc -l 0 Fixes: d23b8ad8ab23 ("tc: add BPF based action") Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-07-30 00:40:56 +08:00
tcf_bpf_cfg_cleanup(&tmp);
}
static int tcf_bpf_walker(struct net *net, struct sk_buff *skb,
struct netlink_callback *cb, int type,
const struct tc_action_ops *ops,
struct netlink_ext_ack *extack)
{
struct tc_action_net *tn = net_generic(net, bpf_net_id);
return tcf_generic_walker(tn, skb, cb, type, ops, extack);
}
static int tcf_bpf_search(struct net *net, struct tc_action **a, u32 index)
{
struct tc_action_net *tn = net_generic(net, bpf_net_id);
return tcf_idr_search(tn, a, index);
}
static struct tc_action_ops act_bpf_ops __read_mostly = {
.kind = "bpf",
.id = TCA_ID_BPF,
.owner = THIS_MODULE,
.act = tcf_bpf_act,
.dump = tcf_bpf_dump,
.cleanup = tcf_bpf_cleanup,
.init = tcf_bpf_init,
.walk = tcf_bpf_walker,
.lookup = tcf_bpf_search,
.size = sizeof(struct tcf_bpf),
};
static __net_init int bpf_init_net(struct net *net)
{
struct tc_action_net *tn = net_generic(net, bpf_net_id);
return tc_action_net_init(net, tn, &act_bpf_ops);
}
static void __net_exit bpf_exit_net(struct list_head *net_list)
{
tc_action_net_exit(net_list, bpf_net_id);
}
static struct pernet_operations bpf_net_ops = {
.init = bpf_init_net,
.exit_batch = bpf_exit_net,
.id = &bpf_net_id,
.size = sizeof(struct tc_action_net),
};
static int __init bpf_init_module(void)
{
return tcf_register_action(&act_bpf_ops, &bpf_net_ops);
}
static void __exit bpf_cleanup_module(void)
{
tcf_unregister_action(&act_bpf_ops, &bpf_net_ops);
}
module_init(bpf_init_module);
module_exit(bpf_cleanup_module);
MODULE_AUTHOR("Jiri Pirko <jiri@resnulli.us>");
MODULE_DESCRIPTION("TC BPF based action");
MODULE_LICENSE("GPL v2");