linux/net
Dmitrii Banshchikov 5e0bc3082e bpf: Forbid bpf_ktime_get_coarse_ns and bpf_timer_* in tracing progs
Use of bpf_ktime_get_coarse_ns() and bpf_timer_* helpers in tracing
progs may result in locking issues.

bpf_ktime_get_coarse_ns() uses ktime_get_coarse_ns() time accessor that
isn't safe for any context:
======================================================
WARNING: possible circular locking dependency detected
5.15.0-syzkaller #0 Not tainted
------------------------------------------------------
syz-executor.4/14877 is trying to acquire lock:
ffffffff8cb30008 (tk_core.seq.seqcount){----}-{0:0}, at: ktime_get_coarse_ts64+0x25/0x110 kernel/time/timekeeping.c:2255

but task is already holding lock:
ffffffff90dbf200 (&obj_hash[i].lock){-.-.}-{2:2}, at: debug_object_deactivate+0x61/0x400 lib/debugobjects.c:735

which lock already depends on the new lock.

the existing dependency chain (in reverse order) is:

-> #1 (&obj_hash[i].lock){-.-.}-{2:2}:
       lock_acquire+0x19f/0x4d0 kernel/locking/lockdep.c:5625
       __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
       _raw_spin_lock_irqsave+0xd1/0x120 kernel/locking/spinlock.c:162
       __debug_object_init+0xd9/0x1860 lib/debugobjects.c:569
       debug_hrtimer_init kernel/time/hrtimer.c:414 [inline]
       debug_init kernel/time/hrtimer.c:468 [inline]
       hrtimer_init+0x20/0x40 kernel/time/hrtimer.c:1592
       ntp_init_cmos_sync kernel/time/ntp.c:676 [inline]
       ntp_init+0xa1/0xad kernel/time/ntp.c:1095
       timekeeping_init+0x512/0x6bf kernel/time/timekeeping.c:1639
       start_kernel+0x267/0x56e init/main.c:1030
       secondary_startup_64_no_verify+0xb1/0xbb

-> #0 (tk_core.seq.seqcount){----}-{0:0}:
       check_prev_add kernel/locking/lockdep.c:3051 [inline]
       check_prevs_add kernel/locking/lockdep.c:3174 [inline]
       validate_chain+0x1dfb/0x8240 kernel/locking/lockdep.c:3789
       __lock_acquire+0x1382/0x2b00 kernel/locking/lockdep.c:5015
       lock_acquire+0x19f/0x4d0 kernel/locking/lockdep.c:5625
       seqcount_lockdep_reader_access+0xfe/0x230 include/linux/seqlock.h:103
       ktime_get_coarse_ts64+0x25/0x110 kernel/time/timekeeping.c:2255
       ktime_get_coarse include/linux/timekeeping.h:120 [inline]
       ktime_get_coarse_ns include/linux/timekeeping.h:126 [inline]
       ____bpf_ktime_get_coarse_ns kernel/bpf/helpers.c:173 [inline]
       bpf_ktime_get_coarse_ns+0x7e/0x130 kernel/bpf/helpers.c:171
       bpf_prog_a99735ebafdda2f1+0x10/0xb50
       bpf_dispatcher_nop_func include/linux/bpf.h:721 [inline]
       __bpf_prog_run include/linux/filter.h:626 [inline]
       bpf_prog_run include/linux/filter.h:633 [inline]
       BPF_PROG_RUN_ARRAY include/linux/bpf.h:1294 [inline]
       trace_call_bpf+0x2cf/0x5d0 kernel/trace/bpf_trace.c:127
       perf_trace_run_bpf_submit+0x7b/0x1d0 kernel/events/core.c:9708
       perf_trace_lock+0x37c/0x440 include/trace/events/lock.h:39
       trace_lock_release+0x128/0x150 include/trace/events/lock.h:58
       lock_release+0x82/0x810 kernel/locking/lockdep.c:5636
       __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:149 [inline]
       _raw_spin_unlock_irqrestore+0x75/0x130 kernel/locking/spinlock.c:194
       debug_hrtimer_deactivate kernel/time/hrtimer.c:425 [inline]
       debug_deactivate kernel/time/hrtimer.c:481 [inline]
       __run_hrtimer kernel/time/hrtimer.c:1653 [inline]
       __hrtimer_run_queues+0x2f9/0xa60 kernel/time/hrtimer.c:1749
       hrtimer_interrupt+0x3b3/0x1040 kernel/time/hrtimer.c:1811
       local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1086 [inline]
       __sysvec_apic_timer_interrupt+0xf9/0x270 arch/x86/kernel/apic/apic.c:1103
       sysvec_apic_timer_interrupt+0x8c/0xb0 arch/x86/kernel/apic/apic.c:1097
       asm_sysvec_apic_timer_interrupt+0x12/0x20
       __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline]
       _raw_spin_unlock_irqrestore+0xd4/0x130 kernel/locking/spinlock.c:194
       try_to_wake_up+0x702/0xd20 kernel/sched/core.c:4118
       wake_up_process kernel/sched/core.c:4200 [inline]
       wake_up_q+0x9a/0xf0 kernel/sched/core.c:953
       futex_wake+0x50f/0x5b0 kernel/futex/waitwake.c:184
       do_futex+0x367/0x560 kernel/futex/syscalls.c:127
       __do_sys_futex kernel/futex/syscalls.c:199 [inline]
       __se_sys_futex+0x401/0x4b0 kernel/futex/syscalls.c:180
       do_syscall_x64 arch/x86/entry/common.c:50 [inline]
       do_syscall_64+0x44/0xd0 arch/x86/entry/common.c:80
       entry_SYSCALL_64_after_hwframe+0x44/0xae

There is a possible deadlock with bpf_timer_* set of helpers:
hrtimer_start()
  lock_base();
  trace_hrtimer...()
    perf_event()
      bpf_run()
        bpf_timer_start()
          hrtimer_start()
            lock_base()         <- DEADLOCK

Forbid use of bpf_ktime_get_coarse_ns() and bpf_timer_* helpers in
BPF_PROG_TYPE_KPROBE, BPF_PROG_TYPE_TRACEPOINT, BPF_PROG_TYPE_PERF_EVENT
and BPF_PROG_TYPE_RAW_TRACEPOINT prog types.

Fixes: d055126180 ("bpf: Add bpf_ktime_get_coarse_ns helper")
Fixes: b00628b1c7 ("bpf: Introduce bpf timers.")
Reported-by: syzbot+43fd005b5a1b4d10781e@syzkaller.appspotmail.com
Signed-off-by: Dmitrii Banshchikov <me@ubique.spb.ru>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20211113142227.566439-2-me@ubique.spb.ru
2021-11-15 20:35:58 -08:00
..
6lowpan 6lowpan: iphc: Fix an off-by-one check of array index 2021-07-22 16:19:03 +02:00
9p 9p: fix a bunch of checkpatch warnings 2021-11-04 21:04:25 +09:00
802 llc/snap: constify dev_addr passing 2021-10-13 09:40:46 -07:00
8021q net: vlan: fix a UAF in vlan_dev_real_dev() 2021-11-03 14:19:23 +00:00
appletalk net: socket: rework compat_ifreq_ioctl() 2021-07-23 14:20:25 +01:00
atm net: atm: use address setting helpers 2021-10-24 13:59:45 +01:00
ax25 ax25: constify dev_addr passing 2021-10-13 09:40:45 -07:00
batman-adv Merge branch 'exit-cleanups-for-v5.16' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace 2021-11-10 16:15:54 -08:00
bluetooth bluetooth: use dev_addr_set() 2021-10-25 11:01:29 -07:00
bpf bpf: Add dummy BPF STRUCT_OPS for test purpose 2021-11-01 14:10:00 -07:00
bpfilter bpfilter: Specify the log level for the kmsg message 2021-06-25 13:13:50 +02:00
bridge Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2021-11-01 20:05:14 -07:00
caif net: caif: get ready for const netdev->dev_addr 2021-10-24 13:59:45 +01:00
can can: j1939: j1939_tp_cmd_recv(): check the dst address of TP.CM_BAM 2021-11-06 17:29:32 +01:00
ceph Networking changes for 5.14. 2021-06-30 15:51:09 -07:00
core bpf: Forbid bpf_ktime_get_coarse_ns and bpf_timer_* in tracing progs 2021-11-15 20:35:58 -08:00
dcb
dccp tcp: switch orphan_count to bare per-cpu counters 2021-10-15 11:28:34 +01:00
decnet net: Remove redundant if statements 2021-08-05 13:27:50 +01:00
dns_resolver
dsa net: dsa: felix: fix broken VLAN-tagged PTP under VLAN-aware bridge 2021-11-03 14:22:00 +00:00
ethernet eth: platform: add a helper for loading netdev->dev_addr 2021-10-08 14:54:33 +01:00
ethtool ethtool: fix ethtool msg len calculation for pause stats 2021-11-03 11:20:45 +00:00
hsr net: hsr: Add support for redbox supervision frames 2021-10-26 14:52:17 +01:00
ieee802154 mac802154: use dev_addr_set() - manual 2021-10-20 14:27:40 +01:00
ife
ipv4 bpf: Forbid bpf_ktime_get_coarse_ns and bpf_timer_* in tracing progs 2021-11-15 20:35:58 -08:00
ipv6 ipv6: remove useless assignment to newinet in tcp_v6_syn_recv_sock() 2021-11-05 19:49:40 -07:00
iucv net/iucv: Replace deprecated CPU-hotplug functions. 2021-08-09 10:13:32 +01:00
kcm net: sock: introduce sk_error_report 2021-06-29 11:28:21 -07:00
key
l2tp net/l2tp: Fix reference count leak in l2tp_udp_recv_core 2021-09-09 11:00:20 +01:00
l3mdev
lapb
llc llc/snap: constify dev_addr passing 2021-10-13 09:40:46 -07:00
mac80211 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2021-10-28 10:43:58 -07:00
mac802154 mac802154: use dev_addr_set() - manual 2021-10-20 14:27:40 +01:00
mctp mctp: handle the struct sockaddr_mctp_ext padding field 2021-11-04 19:17:48 -07:00
mpls mpls: defer ttl decrement in mpls_forward() 2021-07-23 17:17:56 +01:00
mptcp Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2021-10-28 10:43:58 -07:00
ncsi net/ncsi: add get MAC address command to get Intel i210 MAC address 2021-09-01 17:18:56 -07:00
netfilter Networking fixes for 5.16-rc1, including fixes from bpf, can 2021-11-11 09:49:36 -08:00
netlabel net: fix NULL pointer reference in cipso_v4_doi_free 2021-08-30 12:23:18 +01:00
netlink Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2021-10-07 15:24:06 -07:00
netrom ax25: constify dev_addr passing 2021-10-13 09:40:45 -07:00
nfc Networking fixes for 5.16-rc1, including fixes from bpf, can 2021-11-11 09:49:36 -08:00
nsh
openvswitch include/linux/mm.h: move nr_free_buffer_pages from swap.h to mm.h 2021-11-06 13:30:43 -07:00
packet af_packet: Introduce egress hook 2021-10-14 23:06:44 +02:00
phonet net: Remove redundant if statements 2021-08-05 13:27:50 +01:00
psample
qrtr net: qrtr: combine nameservice into main module 2021-09-28 17:36:43 -07:00
rds net/rds: dma_map_sg is entitled to merge entries 2021-08-18 15:35:50 -07:00
rfkill
rose rose: constify dev_addr passing 2021-10-13 09:40:45 -07:00
rxrpc rxrpc: Fix _usecs_to_jiffies() by using usecs_to_jiffies() 2021-09-24 14:18:34 +01:00
sched net/sched: sch_taprio: fix undefined behavior in ktime_mono_to_any 2021-11-09 19:16:23 -08:00
sctp Networking fixes for 5.16-rc1, including fixes from bpf, can 2021-11-11 09:49:36 -08:00
smc net/smc: fix sk_refcnt underflow on linkdown and fallback 2021-11-10 14:43:59 +00:00
strparser bpf: sockmap, strparser, and tls are reusing qdisc_skb_cb and colliding 2021-11-09 01:05:28 +01:00
sunrpc A slow cycle for nfsd: mainly cleanup, including Neil's patch dropping 2021-11-10 16:45:54 -08:00
switchdev net: switchdev: merge switchdev_handle_fdb_{add,del}_to_device 2021-10-27 14:54:02 +01:00
tipc Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2021-10-28 10:43:58 -07:00
tls Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2021-10-28 10:43:58 -07:00
unix net: Implement ->sock_is_readable() for UDP and AF_UNIX 2021-10-26 12:29:33 -07:00
vmw_vsock vsock: prevent unnecessary refcnt inc for nonblocking connect 2021-11-10 14:36:11 +00:00
wireless Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2021-10-28 10:43:58 -07:00
x25
xdp xsk: Fix crash on double free in buffer pool 2021-11-12 15:55:27 +01:00
xfrm Core: 2021-11-02 06:20:58 -07:00
compat.c
devres.c
Kconfig net/core: disable NET_RX_BUSY_POLL on PREEMPT_RT 2021-10-01 15:45:10 -07:00
Makefile mctp: Add MCTP base 2021-07-29 15:06:49 +01:00
socket.c Core: 2021-08-31 16:43:06 -07:00
sysctl_net.c sections: move and rename core_kernel_data() to is_kernel_core_data() 2021-11-09 10:02:50 -08:00