After commit 0f6925b3e8 ("virtio_net: Do not pull payload in skb->head")
Guenter Roeck reported one failure in his tests using sh architecture.
After much debugging, we have been able to spot silent unaligned accesses
in inet_gro_receive()
The issue at hand is that upper networking stacks assume their header
is word-aligned. Low level drivers are supposed to reserve NET_IP_ALIGN
bytes before the Ethernet header to make that happen.
This patch hardens skb_gro_reset_offset() to not allow frag0 fast-path
if the fragment is not properly aligned.
Some arches like x86, arm64 and powerpc do not care and define NET_IP_ALIGN
as 0, this extra check will be a NOP for them.
Note that if frag0 is not used, GRO will call pskb_may_pull()
as many times as needed to pull network and transport headers.
Fixes: 0f6925b3e8 ("virtio_net: Do not pull payload in skb->head")
Fixes: 78a478d0ef ("gro: Inline skb_gro_header and cache frag0 virtual address")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: Guenter Roeck <linux@roeck-us.net>
Cc: Xuan Zhuo <xuanzhuo@linux.alibaba.com>
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Jason Wang <jasowang@redhat.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Tested-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
napi_disable() is subject to an hangup, when the threaded
mode is enabled and the napi is under heavy traffic.
If the relevant napi has been scheduled and the napi_disable()
kicks in before the next napi_threaded_wait() completes - so
that the latter quits due to the napi_disable_pending() condition,
the existing code leaves the NAPI_STATE_SCHED bit set and the
napi_disable() loop waiting for such bit will hang.
This patch addresses the issue by dropping the NAPI_STATE_DISABLE
bit test in napi_thread_wait(). The later napi_threaded_poll()
iteration will take care of clearing the NAPI_STATE_SCHED.
This also addresses a related problem reported by Jakub:
before this patch a napi_disable()/napi_enable() pair killed
the napi thread, effectively disabling the threaded mode.
On the patched kernel napi_disable() simply stops scheduling
the relevant thread.
v1 -> v2:
- let the main napi_thread_poll() loop clear the SCHED bit
Reported-by: Jakub Kicinski <kuba@kernel.org>
Fixes: 29863d41bb ("net: implement threaded-able napi poll loop support")
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://lore.kernel.org/r/883923fa22745a9589e8610962b7dc59df09fb1f.1617981844.git.pabeni@redhat.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Daniel Borkmann says:
====================
pull-request: bpf 2021-04-08
The following pull-request contains BPF updates for your *net* tree.
We've added 4 non-merge commits during the last 2 day(s) which contain
a total of 4 files changed, 31 insertions(+), 10 deletions(-).
The main changes are:
1) Validate and reject invalid JIT branch displacements, from Piotr Krysiuk.
2) Fix incorrect unhash restore as well as fwd_alloc memory accounting in
sock map, from John Fastabend.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Setting iftoken can fail for several different reasons but there
and there was no report to user as to the cause. Add netlink
extended errors to the processing of the request.
This requires adding additional argument through rtnl_af_ops
set_link_af callback.
Reported-by: Hongren Zheng <li@zenithal.me>
Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
Reviewed-by: David Ahern <dsahern@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Incorrect accounting fwd_alloc can result in a warning when the socket
is torn down,
[18455.319240] WARNING: CPU: 0 PID: 24075 at net/core/stream.c:208 sk_stream_kill_queues+0x21f/0x230
[...]
[18455.319543] Call Trace:
[18455.319556] inet_csk_destroy_sock+0xba/0x1f0
[18455.319577] tcp_rcv_state_process+0x1b4e/0x2380
[18455.319593] ? lock_downgrade+0x3a0/0x3a0
[18455.319617] ? tcp_finish_connect+0x1e0/0x1e0
[18455.319631] ? sk_reset_timer+0x15/0x70
[18455.319646] ? tcp_schedule_loss_probe+0x1b2/0x240
[18455.319663] ? lock_release+0xb2/0x3f0
[18455.319676] ? __release_sock+0x8a/0x1b0
[18455.319690] ? lock_downgrade+0x3a0/0x3a0
[18455.319704] ? lock_release+0x3f0/0x3f0
[18455.319717] ? __tcp_close+0x2c6/0x790
[18455.319736] ? tcp_v4_do_rcv+0x168/0x370
[18455.319750] tcp_v4_do_rcv+0x168/0x370
[18455.319767] __release_sock+0xbc/0x1b0
[18455.319785] __tcp_close+0x2ee/0x790
[18455.319805] tcp_close+0x20/0x80
This currently happens because on redirect case we do skb_set_owner_r()
with the original sock. This increments the fwd_alloc memory accounting
on the original sock. Then on redirect we may push this into the queue
of the psock we are redirecting to. When the skb is flushed from the
queue we give the memory back to the original sock. The problem is if
the original sock is destroyed/closed with skbs on another psocks queue
then the original sock will not have a way to reclaim the memory before
being destroyed. Then above warning will be thrown
sockA sockB
sk_psock_strp_read()
sk_psock_verdict_apply()
-- SK_REDIRECT --
sk_psock_skb_redirect()
skb_queue_tail(psock_other->ingress_skb..)
sk_close()
sock_map_unref()
sk_psock_put()
sk_psock_drop()
sk_psock_zap_ingress()
At this point we have torn down our own psock, but have the outstanding
skb in psock_other. Note that SK_PASS doesn't have this problem because
the sk_psock_drop() logic releases the skb, its still associated with
our psock.
To resolve lets only account for sockets on the ingress queue that are
still associated with the current socket. On the redirect case we will
check memory limits per 6fa9201a89, but will omit fwd_alloc accounting
until skb is actually enqueued. When the skb is sent via skb_send_sock_locked
or received with sk_psock_skb_ingress memory will be claimed on psock_other.
Fixes: 6fa9201a89 ("bpf, sockmap: Avoid returning unneeded EAGAIN when redirecting to self")
Reported-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/161731444013.68884.4021114312848535993.stgit@john-XPS-13-9370
xdp_return_frame() may be called outside of NAPI context to return
xdpf back to page_pool. xdp_return_frame() calls __xdp_return() with
napi_direct = false. For page_pool memory model, __xdp_return() calls
xdp_return_frame_no_direct() unconditionally and below false negative
kernel BUG throw happened under preempt-rt build:
[ 430.450355] BUG: using smp_processor_id() in preemptible [00000000] code: modprobe/3884
[ 430.451678] caller is __xdp_return+0x1ff/0x2e0
[ 430.452111] CPU: 0 PID: 3884 Comm: modprobe Tainted: G U E 5.12.0-rc2+ #45
Changes in v2:
- This patch fixes the issue by making xdp_return_frame_no_direct() is
only called if napi_direct = true, as recommended for better by
Jesper Dangaard Brouer. Thanks!
Fixes: 2539650fad ("xdp: Helpers for disabling napi_direct of xdp_return_frame")
Signed-off-by: Ong Boon Leong <boon.leong.ong@intel.com>
Acked-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
After a short network outage, the dst_entry is timed out and put
in DST_OBSOLETE_DEAD. We are in this code because arp reply comes
from this neighbour after network recovers. There is a potential
race condition that dst_entry is still in DST_OBSOLETE_DEAD.
With that, another neighbour lookup causes more harm than good.
In best case all packets in arp_queue are lost. This is
counterproductive to the original goal of finding a better path
for those packets.
I observed a worst case with 4.x kernel where a dst_entry in
DST_OBSOLETE_DEAD state is associated with loopback net_device.
It leads to an ethernet header with all zero addresses.
A packet with all zero source MAC address is quite deadly with
mac80211, ath9k and 802.11 block ack. It fails
ieee80211_find_sta_by_ifaddr in ath9k (xmit.c). Ath9k flushes tx
queue (ath_tx_complete_aggr). BAW (block ack window) is not
updated. BAW logic is damaged and ath9k transmission is disabled.
Signed-off-by: Tong Zhu <zhutong@amazon.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Currently the mentioned helper can end-up freeing the socket wmem
without waking-up any processes waiting for more write memory.
If the partially orphaned skb is attached to an UDP (or raw) socket,
the lack of wake-up can hang the user-space.
Even for TCP sockets not calling the sk destructor could have bad
effects on TSQ.
Address the issue using skb_orphan to release the sk wmem before
setting the new sock_efree destructor. Additionally bundle the
whole ownership update in a new helper, so that later other
potential users could avoid duplicate code.
v1 -> v2:
- use skb_orphan() instead of sort of open coding it (Eric)
- provide an helper for the ownership change (Eric)
Fixes: f6ba8d33cf ("netem: fix skb_orphan_partial()")
Suggested-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
__dev_alloc_name(), when supplied with a name containing '%d',
will search for the first available device number to generate a
unique device name.
Since commit ff92741270 ("net:
introduce name_node struct to be used in hashlist") network
devices may have alternate names. __dev_alloc_name() does take
these alternate names into account, possibly generating a name
that is already taken and failing with -ENFILE as a result.
This demonstrates the bug:
# rmmod dummy 2>/dev/null
# ip link property add dev lo altname dummy0
# modprobe dummy numdummies=1
modprobe: ERROR: could not insert 'dummy': Too many open files in system
Instead of creating a device named dummy1, modprobe fails.
Fix this by checking all the names in the d->name_node list, not just d->name.
Signed-off-by: Jiri Bohac <jbohac@suse.cz>
Fixes: ff92741270 ("net: introduce name_node struct to be used in hashlist")
Reviewed-by: Jiri Pirko <jiri@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Currently, napi_thread_wait() checks for NAPI_STATE_SCHED bit to
determine if the kthread owns this napi and could call napi->poll() on
it. However, if socket busy poll is enabled, it is possible that the
busy poll thread grabs this SCHED bit (after the previous napi->poll()
invokes napi_complete_done() and clears SCHED bit) and tries to poll
on the same napi. napi_disable() could grab the SCHED bit as well.
This patch tries to fix this race by adding a new bit
NAPI_STATE_SCHED_THREADED in napi->state. This bit gets set in
____napi_schedule() if the threaded mode is enabled, and gets cleared
in napi_complete_done(), and we only poll the napi in kthread if this
bit is set. This helps distinguish the ownership of the napi between
kthread and other scenarios and fixes the race issue.
Fixes: 29863d41bb ("net: implement threaded-able napi poll loop support")
Reported-by: Martin Zaharinov <micron10@gmail.com>
Suggested-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Wei Wang <weiwan@google.com>
Cc: Alexander Duyck <alexanderduyck@fb.com>
Cc: Eric Dumazet <edumazet@google.com>
Cc: Paolo Abeni <pabeni@redhat.com>
Cc: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
When a non-initial netns is destroyed, the usual policy is to delete
all virtual network interfaces contained, but move physical interfaces
back to the initial netns. This keeps the physical interface visible
on the system.
CAN devices are somewhat special, as they define rtnl_link_ops even
if they are physical devices. If a CAN interface is moved into a
non-initial netns, destroying that netns lets the interface vanish
instead of moving it back to the initial netns. default_device_exit()
skips CAN interfaces due to having rtnl_link_ops set. Reproducer:
ip netns add foo
ip link set can0 netns foo
ip netns delete foo
WARNING: CPU: 1 PID: 84 at net/core/dev.c:11030 ops_exit_list+0x38/0x60
CPU: 1 PID: 84 Comm: kworker/u4:2 Not tainted 5.10.19 #1
Workqueue: netns cleanup_net
[<c010e700>] (unwind_backtrace) from [<c010a1d8>] (show_stack+0x10/0x14)
[<c010a1d8>] (show_stack) from [<c086dc10>] (dump_stack+0x94/0xa8)
[<c086dc10>] (dump_stack) from [<c086b938>] (__warn+0xb8/0x114)
[<c086b938>] (__warn) from [<c086ba10>] (warn_slowpath_fmt+0x7c/0xac)
[<c086ba10>] (warn_slowpath_fmt) from [<c0629f20>] (ops_exit_list+0x38/0x60)
[<c0629f20>] (ops_exit_list) from [<c062a5c4>] (cleanup_net+0x230/0x380)
[<c062a5c4>] (cleanup_net) from [<c0142c20>] (process_one_work+0x1d8/0x438)
[<c0142c20>] (process_one_work) from [<c0142ee4>] (worker_thread+0x64/0x5a8)
[<c0142ee4>] (worker_thread) from [<c0148a98>] (kthread+0x148/0x14c)
[<c0148a98>] (kthread) from [<c0100148>] (ret_from_fork+0x14/0x2c)
To properly restore physical CAN devices to the initial netns on owning
netns exit, introduce a flag on rtnl_link_ops that can be set by drivers.
For CAN devices setting this flag, default_device_exit() considers them
non-virtual, applying the usual namespace move.
The issue was introduced in the commit mentioned below, as at that time
CAN devices did not have a dellink() operation.
Fixes: e008b5fc8d ("net: Simplfy default_device_exit and improve batching.")
Link: https://lore.kernel.org/r/20210302122423.872326-1-martin@strongswan.org
Signed-off-by: Martin Willi <martin@strongswan.org>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
flow_dissector_key_icmp::id is of type u16 (CPU byteorder),
ICMP header has its ID field in network byteorder obviously.
Sparse says:
net/core/flow_dissector.c:178:43: warning: restricted __be16 degrades to integer
Convert ID value to CPU byteorder when storing it into
flow_dissector_key_icmp.
Fixes: 5dec597e5c ("flow_dissector: extract more ICMP information")
Signed-off-by: Alexander Lobakin <alobakin@pm.me>
Signed-off-by: David S. Miller <davem@davemloft.net>
Introduce the new function tw_prot_init (inspired by
req_prot_init) to simplify "proto_register" function.
tw_prot_cleanup will take care of a partially initialized
timewait_sock_ops.
Signed-off-by: Tonghao Zhang <xiangxia.m.yue@gmail.com>
Reviewed-by: Alexander Duyck <alexanderduyck@fb.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
In the rare case that drop_monitor fails to register its probe on the
'napi_poll' tracepoint, it will not deactivate its hysteresis timer as
part of the error path. If the hysteresis timer was armed by the shortly
lived 'kfree_skb' probe and user space retries to initiate tracing, a
warning will be emitted for trying to initialize an active object [1].
Fix this by properly undoing all the operations that were done prior to
probe registration, in both software and hardware code paths.
Note that syzkaller managed to fail probe registration by injecting a
slab allocation failure [2].
[1]
ODEBUG: init active (active state 0) object type: timer_list hint: sched_send_work+0x0/0x60 include/linux/list.h:135
WARNING: CPU: 1 PID: 8649 at lib/debugobjects.c:505 debug_print_object+0x16e/0x250 lib/debugobjects.c:505
Modules linked in:
CPU: 1 PID: 8649 Comm: syz-executor.0 Not tainted 5.11.0-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:debug_print_object+0x16e/0x250 lib/debugobjects.c:505
[...]
Call Trace:
__debug_object_init+0x524/0xd10 lib/debugobjects.c:588
debug_timer_init kernel/time/timer.c:722 [inline]
debug_init kernel/time/timer.c:770 [inline]
init_timer_key+0x2d/0x340 kernel/time/timer.c:814
net_dm_trace_on_set net/core/drop_monitor.c:1111 [inline]
set_all_monitor_traces net/core/drop_monitor.c:1188 [inline]
net_dm_monitor_start net/core/drop_monitor.c:1295 [inline]
net_dm_cmd_trace+0x720/0x1220 net/core/drop_monitor.c:1339
genl_family_rcv_msg_doit+0x228/0x320 net/netlink/genetlink.c:739
genl_family_rcv_msg net/netlink/genetlink.c:783 [inline]
genl_rcv_msg+0x328/0x580 net/netlink/genetlink.c:800
netlink_rcv_skb+0x153/0x420 net/netlink/af_netlink.c:2502
genl_rcv+0x24/0x40 net/netlink/genetlink.c:811
netlink_unicast_kernel net/netlink/af_netlink.c:1312 [inline]
netlink_unicast+0x533/0x7d0 net/netlink/af_netlink.c:1338
netlink_sendmsg+0x856/0xd90 net/netlink/af_netlink.c:1927
sock_sendmsg_nosec net/socket.c:652 [inline]
sock_sendmsg+0xcf/0x120 net/socket.c:672
____sys_sendmsg+0x6e8/0x810 net/socket.c:2348
___sys_sendmsg+0xf3/0x170 net/socket.c:2402
__sys_sendmsg+0xe5/0x1b0 net/socket.c:2435
do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
entry_SYSCALL_64_after_hwframe+0x44/0xae
[2]
FAULT_INJECTION: forcing a failure.
name failslab, interval 1, probability 0, space 0, times 1
CPU: 1 PID: 8645 Comm: syz-executor.0 Not tainted 5.11.0-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
dump_stack+0xfa/0x151
should_fail.cold+0x5/0xa
should_failslab+0x5/0x10
__kmalloc+0x72/0x3f0
tracepoint_add_func+0x378/0x990
tracepoint_probe_register+0x9c/0xe0
net_dm_cmd_trace+0x7fc/0x1220
genl_family_rcv_msg_doit+0x228/0x320
genl_rcv_msg+0x328/0x580
netlink_rcv_skb+0x153/0x420
genl_rcv+0x24/0x40
netlink_unicast+0x533/0x7d0
netlink_sendmsg+0x856/0xd90
sock_sendmsg+0xcf/0x120
____sys_sendmsg+0x6e8/0x810
___sys_sendmsg+0xf3/0x170
__sys_sendmsg+0xe5/0x1b0
do_syscall_64+0x2d/0x70
entry_SYSCALL_64_after_hwframe+0x44/0xae
Fixes: 70c69274f3 ("drop_monitor: Initialize timer and work item upon tracing enable")
Fixes: 8ee2267ad3 ("drop_monitor: Convert to using devlink tracepoint")
Reported-by: syzbot+779559d6503f3a56213d@syzkaller.appspotmail.com
Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Reviewed-by: Jiri Pirko <jiri@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Daniel Borkmann says:
====================
pull-request: bpf 2021-03-10
The following pull-request contains BPF updates for your *net* tree.
We've added 8 non-merge commits during the last 5 day(s) which contain
a total of 11 files changed, 136 insertions(+), 17 deletions(-).
The main changes are:
1) Reject bogus use of vmlinux BTF as map/prog creation BTF, from Alexei Starovoitov.
2) Fix allocation failure splat in x86 JIT for large progs. Also fix overwriting
percpu cgroup storage from tracing programs when nested, from Yonghong Song.
3) Fix rx queue retrieval in XDP for multi-queue veth, from Maciej Fijalkowski.
4) Fix bpf_check_mtu() helper API before freeze to have mtu_len as custom skb/xdp
L3 input length, from Jesper Dangaard Brouer.
5) Fix inode_storage's lookup_elem return value upon having bad fd, from Tal Lossos.
6) Fix bpftool and libbpf cross-build on MacOS, from Georgi Valkov.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
I ran into a crash where setting up a ip6ip6 tunnel device which was /not/
set to collect_md mode was receiving collect_md populated skbs for xmit.
The BPF prog was populating the skb via bpf_skb_set_tunnel_key() which is
assigning special metadata dst entry and then redirecting the skb to the
device, taking ip6_tnl_start_xmit() -> ipxip6_tnl_xmit() -> ip6_tnl_xmit()
and in the latter it performs a neigh lookup based on skb_dst(skb) where
we trigger a NULL pointer dereference on dst->ops->neigh_lookup() since
the md_dst_ops do not populate neigh_lookup callback with a fake handler.
Transform the md_dst_ops into generic dst_blackhole_ops that can also be
reused elsewhere when needed, and use them for the metadata dst entries as
callback ops.
Also, remove the dst_md_discard{,_out}() ops and rely on dst_discard{,_out}()
from dst_init() which free the skb the same way modulo the splat. Given we
will be able to recover just fine from there, avoid any potential splats
iff this gets ever triggered in future (or worse, panic on warns when set).
Fixes: f38a9eb1f7 ("dst: Metadata destinations")
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Move generic blackhole dst ops to the core and use them from both
ipv4_dst_blackhole_ops and ip6_dst_blackhole_ops where possible. No
functional change otherwise. We need these also in other locations
and having to define them over and over again is not great.
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
The FIB lookup example[1] show how the IP-header field tot_len
(iph->tot_len) is used as input to perform the MTU check.
This patch extend the BPF-helper bpf_check_mtu() with the same ability
to provide the length as user parameter input, via mtu_len parameter.
This still needs to be done before the bpf_check_mtu() helper API
becomes frozen.
[1] samples/bpf/xdp_fwd_kern.c
Fixes: 34b2021cc6 ("bpf: Add BPF-helper for MTU checking")
Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/bpf/161521555850.3515614.6533850861569774444.stgit@firesoul
The recent addition of in_serving_softirq() to kconv.h results in
compile failure on PREEMPT_RT because it requires
task_struct::softirq_disable_cnt. This is not available if kconv.h is
included from sched.h.
It is not needed to include kconv.h from sched.h. All but the net/ user
already include the kconv header file.
Move the include of the kconv.h header from sched.h it its users.
Additionally include sched.h from kconv.h to ensure that everything
task_struct related is available.
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Johannes Berg <johannes@sipsolutions.net>
Acked-by: Andrey Konovalov <andreyknvl@google.com>
Link: https://lkml.kernel.org/r/20210218173124.iy5iyqv3a4oia4vv@linutronix.de
The referenced commit expands the skb_seq_state used by
skb_find_text with a 4B frag_off field, growing it to 48B.
This exceeds container ts_state->cb, causing a stack corruption:
[ 73.238353] Kernel panic - not syncing: stack-protector: Kernel stack
is corrupted in: skb_find_text+0xc5/0xd0
[ 73.247384] CPU: 1 PID: 376 Comm: nping Not tainted 5.11.0+ #4
[ 73.252613] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996),
BIOS 1.14.0-2 04/01/2014
[ 73.260078] Call Trace:
[ 73.264677] dump_stack+0x57/0x6a
[ 73.267866] panic+0xf6/0x2b7
[ 73.270578] ? skb_find_text+0xc5/0xd0
[ 73.273964] __stack_chk_fail+0x10/0x10
[ 73.277491] skb_find_text+0xc5/0xd0
[ 73.280727] string_mt+0x1f/0x30
[ 73.283639] ipt_do_table+0x214/0x410
The struct is passed between skb_find_text and its callbacks
skb_prepare_seq_read, skb_seq_read and skb_abort_seq read through
the textsearch interface using TS_SKB_CB.
I assumed that this mapped to skb->cb like other .._SKB_CB wrappers.
skb->cb is 48B. But it maps to ts_state->cb, which is only 40B.
skb->cb was increased from 40B to 48B after ts_state was introduced,
in commit 3e3850e989 ("[NETFILTER]: Fix xfrm lookup in
ip_route_me_harder/ip6_route_me_harder").
Increase ts_state.cb[] to 48 to fit the struct.
Also add a BUILD_BUG_ON to avoid a repeat.
The alternative is to directly add a dependency from textsearch onto
linux/skbuff.h, but I think the intent is textsearch to have no such
dependencies on its callers.
Link: https://bugzilla.kernel.org/show_bug.cgi?id=211911
Fixes: 97550f6fa5 ("net: compound page support in skb_seq_read")
Reported-by: Kris Karas <bugs-a17@moonlit-rail.com>
Signed-off-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Daniel Borkmann says:
====================
pull-request: bpf-next 2021-02-16
The following pull-request contains BPF updates for your *net-next* tree.
There's a small merge conflict between 7eeba1706e ("tcp: Add receive timestamp
support for receive zerocopy.") from net-next tree and 9cacf81f81 ("bpf: Remove
extra lock_sock for TCP_ZEROCOPY_RECEIVE") from bpf-next tree. Resolve as follows:
[...]
lock_sock(sk);
err = tcp_zerocopy_receive(sk, &zc, &tss);
err = BPF_CGROUP_RUN_PROG_GETSOCKOPT_KERN(sk, level, optname,
&zc, &len, err);
release_sock(sk);
[...]
We've added 116 non-merge commits during the last 27 day(s) which contain
a total of 156 files changed, 5662 insertions(+), 1489 deletions(-).
The main changes are:
1) Adds support of pointers to types with known size among global function
args to overcome the limit on max # of allowed args, from Dmitrii Banshchikov.
2) Add bpf_iter for task_vma which can be used to generate information similar
to /proc/pid/maps, from Song Liu.
3) Enable bpf_{g,s}etsockopt() from all sock_addr related program hooks. Allow
rewriting bind user ports from BPF side below the ip_unprivileged_port_start
range, both from Stanislav Fomichev.
4) Prevent recursion on fentry/fexit & sleepable programs and allow map-in-map
as well as per-cpu maps for the latter, from Alexei Starovoitov.
5) Add selftest script to run BPF CI locally. Also enable BPF ringbuffer
for sleepable programs, both from KP Singh.
6) Extend verifier to enable variable offset read/write access to the BPF
program stack, from Andrei Matei.
7) Improve tc & XDP MTU handling and add a new bpf_check_mtu() helper to
query device MTU from programs, from Jesper Dangaard Brouer.
8) Allow bpf_get_socket_cookie() helper also be called from [sleepable] BPF
tracing programs, from Florent Revest.
9) Extend x86 JIT to pad JMPs with NOPs for helping image to converge when
otherwise too many passes are required, from Gary Lin.
10) Verifier fixes on atomics with BPF_FETCH as well as function-by-function
verification both related to zero-extension handling, from Ilya Leoshkevich.
11) Better kernel build integration of resolve_btfids tool, from Jiri Olsa.
12) Batch of AF_XDP selftest cleanups and small performance improvement
for libbpf's xsk map redirect for newer kernels, from Björn Töpel.
13) Follow-up BPF doc and verifier improvements around atomics with
BPF_FETCH, from Brendan Jackman.
14) Permit zero-sized data sections e.g. if ELF .rodata section contains
read-only data from local variables, from Yonghong Song.
15) veth driver skb bulk-allocation for ndo_xdp_xmit, from Lorenzo Bianconi.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
napi_frags_finish() and napi_skb_finish() can only be called inside
NAPI Rx context, so we can feed NAPI cache with skbuff_heads that
got NAPI_MERGED_FREE verdict instead of immediate freeing.
Replace __kfree_skb() with __kfree_skb_defer() in napi_skb_finish()
and move napi_skb_free_stolen_head() to skbuff.c, so it can drop skbs
to NAPI cache.
As many drivers call napi_alloc_skb()/napi_get_frags() on their
receive path, this becomes especially useful.
Signed-off-by: Alexander Lobakin <alobakin@pm.me>
Signed-off-by: David S. Miller <davem@davemloft.net>
{,__}napi_alloc_skb() is mostly used either for optional non-linear
receive methods (usually controlled via Ethtool private flags and off
by default) and/or for Rx copybreaks.
Use __napi_build_skb() here for obtaining skbuff_heads from NAPI cache
instead of inplace allocations. This includes both kmalloc and page
frag paths.
Signed-off-by: Alexander Lobakin <alobakin@pm.me>
Signed-off-by: David S. Miller <davem@davemloft.net>
Reuse the old and forgotten SKB_ALLOC_NAPI to add an option to get
an skbuff_head from the NAPI cache instead of inplace allocation
inside __alloc_skb().
This implies that the function is called from softirq or BH-off
context, not for allocating a clone or from a distant node.
Cc: Alexander Duyck <alexander.duyck@gmail.com> # Simplified flags check
Signed-off-by: Alexander Lobakin <alobakin@pm.me>
Signed-off-by: David S. Miller <davem@davemloft.net>
Instead of just bulk-flushing skbuff_heads queued up through
napi_consume_skb() or __kfree_skb_defer(), try to reuse them
on allocation path.
If the cache is empty on allocation, bulk-allocate the first
16 elements, which is more efficient than per-skb allocation.
If the cache is full on freeing, bulk-wipe the second half of
the cache (32 elements).
This also includes custom KASAN poisoning/unpoisoning to be
double sure there are no use-after-free cases.
To not change current behaviour, introduce a new function,
napi_build_skb(), to optionally use a new approach later
in drivers.
Note on selected bulk size, 16:
- this equals to XDP_BULK_QUEUE_SIZE, DEV_MAP_BULK_SIZE
and especially VETH_XDP_BATCH, which is also used to
bulk-allocate skbuff_heads and was tested on powerful
setups;
- this also showed the best performance in the actual
test series (from the array of {8, 16, 32}).
Suggested-by: Edward Cree <ecree.xilinx@gmail.com> # Divide on two halves
Suggested-by: Eric Dumazet <edumazet@google.com> # KASAN poisoning
Cc: Dmitry Vyukov <dvyukov@google.com> # Help with KASAN
Cc: Paolo Abeni <pabeni@redhat.com> # Reduced batch size
Signed-off-by: Alexander Lobakin <alobakin@pm.me>
Signed-off-by: David S. Miller <davem@davemloft.net>
NAPI cache structures will be used for allocating skbuff_heads,
so move their declarations a bit upper.
Signed-off-by: Alexander Lobakin <alobakin@pm.me>
Signed-off-by: David S. Miller <davem@davemloft.net>
This function isn't much needed as NAPI skb queue gets bulk-freed
anyway when there's no more room, and even may reduce the efficiency
of bulk operations.
It will be even less needed after reusing skb cache on allocation path,
so remove it and this way lighten network softirqs a bit.
Suggested-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Alexander Lobakin <alobakin@pm.me>
Signed-off-by: David S. Miller <davem@davemloft.net>
Just call __build_skb_around() instead of open-coding it.
Signed-off-by: Alexander Lobakin <alobakin@pm.me>
Signed-off-by: David S. Miller <davem@davemloft.net>
Use unlikely() annotations for skbuff_head and data similarly to the
two other allocation functions and remove totally redundant goto.
Signed-off-by: Alexander Lobakin <alobakin@pm.me>
Signed-off-by: David S. Miller <davem@davemloft.net>
__build_skb_around() can never fail and always returns passed skb.
Make it return void to simplify and optimize the code.
Signed-off-by: Alexander Lobakin <alobakin@pm.me>
Signed-off-by: David S. Miller <davem@davemloft.net>
Eversince the introduction of __kmalloc_reserve(), "ip" argument
hasn't been used. _RET_IP_ is embedded inside
kmalloc_node_track_caller().
Remove the redundant macro and rename the function after it.
Signed-off-by: Alexander Lobakin <alobakin@pm.me>
Signed-off-by: David S. Miller <davem@davemloft.net>
In preparation before reusing several functions in all three skb
allocation variants, move __alloc_skb() next to the
__netdev_alloc_skb() and __napi_alloc_skb().
No functional changes.
Signed-off-by: Alexander Lobakin <alobakin@pm.me>
Signed-off-by: David S. Miller <davem@davemloft.net>
the following command:
# tc filter add dev $h2 ingress protocol ip pref 1 handle 101 flower \
$tcflags dst_ip 192.0.2.2 ip_ttl 63 action drop
doesn't drop all IPv4 packets that match the configured TTL / destination
address. In particular, if "fragment offset" or "more fragments" have non
zero value in the IPv4 header, setting of FLOW_DISSECTOR_KEY_IP is simply
ignored. Fix this dissecting IPv4 TTL and TOS before fragment info; while
at it, add a selftest for tc flower's match on 'ip_ttl' that verifies the
correct behavior.
Fixes: 518d8a2e9b ("net/flow_dissector: add support for dissection of misc ip header fields")
Reported-by: Shuang Li <shuali@redhat.com>
Signed-off-by: Davide Caratti <dcaratti@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The use-case for dropping the MTU check when TC-BPF does redirect to
ingress, is described by Eyal Birger in email[0]. The summary is the
ability to increase packet size (e.g. with IPv6 headers for NAT64) and
ingress redirect packet and let normal netstack fragment packet as needed.
[0] https://lore.kernel.org/netdev/CAHsH6Gug-hsLGHQ6N0wtixdOa85LDZ3HNRHVd0opR=19Qo4W4Q@mail.gmail.com/
V15:
- missing static for function declaration
V9:
- Make net_device "up" (IFF_UP) check explicit in skb_do_redirect
V4:
- Keep net_device "up" (IFF_UP) check.
- Adjustment to handle bpf_redirect_peer() helper
Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/bpf/161287790971.790810.11785274340154740591.stgit@firesoul
This BPF-helper bpf_check_mtu() works for both XDP and TC-BPF programs.
The SKB object is complex and the skb->len value (accessible from
BPF-prog) also include the length of any extra GRO/GSO segments, but
without taking into account that these GRO/GSO segments get added
transport (L4) and network (L3) headers before being transmitted. Thus,
this BPF-helper is created such that the BPF-programmer don't need to
handle these details in the BPF-prog.
The API is designed to help the BPF-programmer, that want to do packet
context size changes, which involves other helpers. These other helpers
usually does a delta size adjustment. This helper also support a delta
size (len_diff), which allow BPF-programmer to reuse arguments needed by
these other helpers, and perform the MTU check prior to doing any actual
size adjustment of the packet context.
It is on purpose, that we allow the len adjustment to become a negative
result, that will pass the MTU check. This might seem weird, but it's not
this helpers responsibility to "catch" wrong len_diff adjustments. Other
helpers will take care of these checks, if BPF-programmer chooses to do
actual size adjustment.
V14:
- Improve man-page desc of len_diff.
V13:
- Enforce flag BPF_MTU_CHK_SEGS cannot use len_diff.
V12:
- Simplify segment check that calls skb_gso_validate_network_len.
- Helpers should return long
V9:
- Use dev->hard_header_len (instead of ETH_HLEN)
- Annotate with unlikely req from Daniel
- Fix logic error using skb_gso_validate_network_len from Daniel
V6:
- Took John's advice and dropped BPF_MTU_CHK_RELAX
- Returned MTU is kept at L3-level (like fib_lookup)
V4: Lot of changes
- ifindex 0 now use current netdev for MTU lookup
- rename helper from bpf_mtu_check to bpf_check_mtu
- fix bug for GSO pkt length (as skb->len is total len)
- remove __bpf_len_adj_positive, simply allow negative len adj
Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/bpf/161287790461.790810.3429728639563297353.stgit@firesoul
The BPF-helpers for FIB lookup (bpf_xdp_fib_lookup and bpf_skb_fib_lookup)
can perform MTU check and return BPF_FIB_LKUP_RET_FRAG_NEEDED. The BPF-prog
don't know the MTU value that caused this rejection.
If the BPF-prog wants to implement PMTU (Path MTU Discovery) (rfc1191) it
need to know this MTU value for the ICMP packet.
Patch change lookup and result struct bpf_fib_lookup, to contain this MTU
value as output via a union with 'tot_len' as this is the value used for
the MTU lookup.
V5:
- Fixed uninit value spotted by Dan Carpenter.
- Name struct output member mtu_result
Reported-by: kernel test robot <lkp@intel.com>
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/bpf/161287789952.790810.13134700381067698781.stgit@firesoul
BPF end-user on Cilium slack-channel (Carlo Carraro) wants to use
bpf_fib_lookup for doing MTU-check, but *prior* to extending packet size,
by adjusting fib_params 'tot_len' with the packet length plus the expected
encap size. (Just like the bpf_check_mtu helper supports). He discovered
that for SKB ctx the param->tot_len was not used, instead skb->len was used
(via MTU check in is_skb_forwardable() that checks against netdev MTU).
Fix this by using fib_params 'tot_len' for MTU check. If not provided (e.g.
zero) then keep existing TC behaviour intact. Notice that 'tot_len' for MTU
check is done like XDP code-path, which checks against FIB-dst MTU.
V16:
- Revert V13 optimization, 2nd lookup is against egress/resulting netdev
V13:
- Only do ifindex lookup one time, calling dev_get_by_index_rcu().
V10:
- Use same method as XDP for 'tot_len' MTU check
Fixes: 4c79579b44 ("bpf: Change bpf_fib_lookup to return lookup status")
Reported-by: Carlo Carraro <colrack@gmail.com>
Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/161287789444.790810.15247494756551413508.stgit@firesoul
Multiple BPF-helpers that can manipulate/increase the size of the SKB uses
__bpf_skb_max_len() as the max-length. This function limit size against
the current net_device MTU (skb->dev->mtu).
When a BPF-prog grow the packet size, then it should not be limited to the
MTU. The MTU is a transmit limitation, and software receiving this packet
should be allowed to increase the size. Further more, current MTU check in
__bpf_skb_max_len uses the MTU from ingress/current net_device, which in
case of redirects uses the wrong net_device.
This patch keeps a sanity max limit of SKB_MAX_ALLOC (16KiB). The real limit
is elsewhere in the system. Jesper's testing[1] showed it was not possible
to exceed 8KiB when expanding the SKB size via BPF-helper. The limiting
factor is the define KMALLOC_MAX_CACHE_SIZE which is 8192 for
SLUB-allocator (CONFIG_SLUB) in-case PAGE_SIZE is 4096. This define is
in-effect due to this being called from softirq context see code
__gfp_pfmemalloc_flags() and __do_kmalloc_node(). Jakub's testing showed
that frames above 16KiB can cause NICs to reset (but not crash). Keep this
sanity limit at this level as memory layer can differ based on kernel
config.
[1] https://github.com/xdp-project/bpf-examples/tree/master/MTU-tests
Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/bpf/161287788936.790810.2937823995775097177.stgit@firesoul
Use a new config SOCK_RX_QUEUE_MAPPING to compile-in the socket
RX queue field and logic, instead of the XPS config.
This breaks dependency in XPS, and allows selecting it from non-XPS
use cases, as we do in the next patch.
In addition, use the new flag to wrap the logic in sk_rx_queue_get()
and protect access to the sk_rx_queue_mapping field, while keeping
the function exposed unconditionally, just like sk_rx_queue_set()
and sk_rx_queue_clear().
Signed-off-by: Tariq Toukan <tariqt@nvidia.com>
Reviewed-by: Maxim Mikityanskiy <maximmi@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
dev_ifsioc_locked() is called with only RCU read lock, so when
there is a parallel writer changing the mac address, it could
get a partially updated mac address, as shown below:
Thread 1 Thread 2
// eth_commit_mac_addr_change()
memcpy(dev->dev_addr, addr->sa_data, ETH_ALEN);
// dev_ifsioc_locked()
memcpy(ifr->ifr_hwaddr.sa_data,
dev->dev_addr,...);
Close this race condition by guarding them with a RW semaphore,
like netdev_get_name(). We can not use seqlock here as it does not
allow blocking. The writers already take RTNL anyway, so this does
not affect the slow path. To avoid bothering existing
dev_set_mac_address() callers in drivers, introduce a new wrapper
just for user-facing callers on ioctl and rtnetlink paths.
Note, bonding also changes slave mac addresses but that requires
a separate patch due to the complexity of bonding code.
Fixes: 3710becf8a ("net: RCU locking for simple ioctl()")
Reported-by: "Gong, Sishuai" <sishuai@purdue.edu>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Cong Wang <cong.wang@bytedance.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This needs a new helper that:
- can work in a sleepable context (using sock_gen_cookie)
- takes a struct sock pointer and checks that it's not NULL
Signed-off-by: Florent Revest <revest@chromium.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: KP Singh <kpsingh@kernel.org>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20210210111406.785541-2-revest@chromium.org
It is simpler to make net->net_cookie a plain u64
written once in setup_net() instead of looping
and using atomic64 helpers.
Lorenz Bauer wants to add SO_NETNS_COOKIE socket option
and this patch would makes his patch series simpler.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Lorenz Bauer <lmb@cloudflare.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Tested-by: Lorenz Bauer <lmb@cloudflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch adds a new sysfs attribute to the network device class.
Said attribute provides a per-device control to enable/disable the
threaded mode for all the napi instances of the given network device,
without the need for a device up/down.
User sets it to 1 or 0 to enable or disable threaded mode.
Note: when switching between threaded and the current softirq based mode
for a napi instance, it will not immediately take effect if the napi is
currently being polled. The mode switch will happen for the next time
napi_schedule() is called.
Co-developed-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Co-developed-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Co-developed-by: Felix Fietkau <nbd@nbd.name>
Signed-off-by: Felix Fietkau <nbd@nbd.name>
Signed-off-by: Wei Wang <weiwan@google.com>
Reviewed-by: Alexander Duyck <alexanderduyck@fb.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch allows running each napi poll loop inside its own
kernel thread.
The kthread is created during netif_napi_add() if dev->threaded
is set. And threaded mode is enabled in napi_enable(). We will
provide a way to set dev->threaded and enable threaded mode
without a device up/down in the following patch.
Once that threaded mode is enabled and the kthread is
started, napi_schedule() will wake-up such thread instead
of scheduling the softirq.
The threaded poll loop behaves quite likely the net_rx_action,
but it does not have to manipulate local irqs and uses
an explicit scheduling point based on netdev_budget.
Co-developed-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Co-developed-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Co-developed-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Wei Wang <weiwan@google.com>
Reviewed-by: Alexander Duyck <alexanderduyck@fb.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit introduces a new function __napi_poll() which does the main
logic of the existing napi_poll() function, and will be called by other
functions in later commits.
This idea and implementation is done by Felix Fietkau <nbd@nbd.name> and
is proposed as part of the patch to move napi work to work_queue
context.
This commit by itself is a code restructure.
Signed-off-by: Felix Fietkau <nbd@nbd.name>
Signed-off-by: Wei Wang <weiwan@google.com>
Reviewed-by: Alexander Duyck <alexanderduyck@fb.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
In order to access the suboordinate dev for a device we should be holding
the rtnl_lock when outside of the transmit path. The existing code was not
doing that for the sysfs dump function and as a result we were open to a
possible race.
To resolve that take the rtnl lock prior to accessing the sb_dev field of
the Tx queue and release it after we have retrieved the tc for the queue.
Signed-off-by: Alexander Duyck <alexanderduyck@fb.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
