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| Kernel | Title | Rank 🛈 | Repro | Cause bisect | Fix bisect | Count | Last | Reported | Patched | Status |
|---|---|---|---|---|---|---|---|---|---|---|
| upstream | possible deadlock in perf_event_for_each_child perf | 4 | 135 | 2833d | 2842d | 0/29 | auto-closed as invalid on 2019/02/22 10:22 | |||
| linux-4.14 | possible deadlock in perf_event_for_each_child | 4 | C | 1482 | 980d | 2396d | 0/1 | upstream: reported C repro on 2019/04/14 09:58 |
======================================================
WARNING: possible circular locking dependency detected
4.14.139+ #34 Not tainted
------------------------------------------------------
syz-executor.3/7353 is trying to acquire lock:
(&event->child_mutex){+.+.}, at: [<00000000b378cbb6>] perf_event_for_each_child+0x82/0x150 kernel/events/core.c:4687
but task is already holding lock:
(&cpuctx_mutex){+.+.}, at: [<000000006e51dfa1>] perf_event_ctx_lock_nested+0x15a/0x2d0 kernel/events/core.c:1240
which lock already depends on the new lock.
the existing dependency chain (in reverse order) is:
-> #8 (&cpuctx_mutex){+.+.}:
__mutex_lock_common kernel/locking/mutex.c:756 [inline]
__mutex_lock+0xf7/0x13e0 kernel/locking/mutex.c:893
perf_event_init_cpu+0xa8/0x150 kernel/events/core.c:11231
perf_event_init+0x289/0x2c5 kernel/events/core.c:11278
start_kernel+0x43d/0x74a init/main.c:621
secondary_startup_64+0xa5/0xb0 arch/x86/kernel/head_64.S:240
-> #7 (pmus_lock){+.+.}:
__mutex_lock_common kernel/locking/mutex.c:756 [inline]
__mutex_lock+0xf7/0x13e0 kernel/locking/mutex.c:893
perf_event_init_cpu+0x2c/0x150 kernel/events/core.c:11225
cpuhp_invoke_callback+0x207/0x1a30 kernel/cpu.c:184
cpuhp_up_callbacks kernel/cpu.c:572 [inline]
_cpu_up+0x20b/0x500 kernel/cpu.c:1134
do_cpu_up+0x64/0x120 kernel/cpu.c:1169
smp_init+0x142/0x154 kernel/smp.c:578
kernel_init_freeable+0x196/0x3b0 init/main.c:1067
kernel_init+0xd/0x164 init/main.c:999
ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:404
-> #6 (cpu_hotplug_lock.rw_sem){++++}:
percpu_down_read_preempt_disable include/linux/percpu-rwsem.h:36 [inline]
percpu_down_read include/linux/percpu-rwsem.h:59 [inline]
cpus_read_lock+0x39/0xc0 kernel/cpu.c:295
get_online_cpus include/linux/cpu.h:140 [inline]
lru_add_drain_all+0xa/0x20 mm/swap.c:729
shmem_wait_for_pins mm/shmem.c:2732 [inline]
shmem_add_seals+0x633/0x11b0 mm/shmem.c:2841
shmem_fcntl+0xea/0x120 mm/shmem.c:2876
do_fcntl+0x5c8/0xd20 fs/fcntl.c:421
SYSC_fcntl fs/fcntl.c:463 [inline]
SyS_fcntl+0xc6/0x100 fs/fcntl.c:448
do_syscall_64+0x19b/0x520 arch/x86/entry/common.c:292
entry_SYSCALL_64_after_hwframe+0x42/0xb7
-> #5 (&sb->s_type->i_mutex_key#10){+.+.}:
down_write+0x34/0x90 kernel/locking/rwsem.c:54
inode_lock include/linux/fs.h:718 [inline]
shmem_fallocate+0x150/0xae0 mm/shmem.c:2902
ashmem_shrink_scan drivers/staging/android/ashmem.c:453 [inline]
ashmem_shrink_scan+0x1ca/0x4f0 drivers/staging/android/ashmem.c:437
ashmem_ioctl+0x2b4/0xd20 drivers/staging/android/ashmem.c:795
vfs_ioctl fs/ioctl.c:46 [inline]
file_ioctl fs/ioctl.c:500 [inline]
do_vfs_ioctl+0xabe/0x1040 fs/ioctl.c:684
SYSC_ioctl fs/ioctl.c:701 [inline]
SyS_ioctl+0x7f/0xb0 fs/ioctl.c:692
do_syscall_64+0x19b/0x520 arch/x86/entry/common.c:292
entry_SYSCALL_64_after_hwframe+0x42/0xb7
-> #4 (ashmem_mutex){+.+.}:
__mutex_lock_common kernel/locking/mutex.c:756 [inline]
__mutex_lock+0xf7/0x13e0 kernel/locking/mutex.c:893
ashmem_mmap+0x4c/0x450 drivers/staging/android/ashmem.c:369
call_mmap include/linux/fs.h:1793 [inline]
mmap_region+0x7d9/0xfb0 mm/mmap.c:1732
do_mmap+0x548/0xb80 mm/mmap.c:1510
do_mmap_pgoff include/linux/mm.h:2209 [inline]
vm_mmap_pgoff+0x177/0x1c0 mm/util.c:333
SYSC_mmap_pgoff mm/mmap.c:1560 [inline]
SyS_mmap_pgoff+0xf4/0x1b0 mm/mmap.c:1518
do_syscall_64+0x19b/0x520 arch/x86/entry/common.c:292
entry_SYSCALL_64_after_hwframe+0x42/0xb7
-> #3 (&mm->mmap_sem){++++}:
__might_fault mm/memory.c:4584 [inline]
__might_fault+0x137/0x1b0 mm/memory.c:4569
_copy_to_user+0x27/0xd0 lib/usercopy.c:25
copy_to_user include/linux/uaccess.h:155 [inline]
filldir+0x198/0x2f0 fs/readdir.c:197
dir_emit_dot include/linux/fs.h:3379 [inline]
dir_emit_dots include/linux/fs.h:3390 [inline]
dcache_readdir+0x123/0x5c0 fs/libfs.c:192
iterate_dir+0x1a5/0x5f0 fs/readdir.c:52
SYSC_getdents fs/readdir.c:232 [inline]
SyS_getdents+0x145/0x290 fs/readdir.c:213
do_syscall_64+0x19b/0x520 arch/x86/entry/common.c:292
entry_SYSCALL_64_after_hwframe+0x42/0xb7
-> #2 (&sb->s_type->i_mutex_key#5){++++}:
down_write+0x34/0x90 kernel/locking/rwsem.c:54
inode_lock include/linux/fs.h:718 [inline]
start_creating.part.0+0x4c/0x150 fs/tracefs/inode.c:335
start_creating fs/tracefs/inode.c:324 [inline]
tracefs_create_file+0x74/0x450 fs/tracefs/inode.c:400
create_event_toplevel_files+0x2d/0x150 kernel/trace/trace_events.c:2909
early_event_add_tracer kernel/trace/trace_events.c:2996 [inline]
event_trace_init+0x312/0x4ec kernel/trace/trace_events.c:3161
do_one_initcall+0xa0/0x1ac init/main.c:825
do_initcall_level init/main.c:891 [inline]
do_initcalls init/main.c:899 [inline]
do_basic_setup init/main.c:917 [inline]
kernel_init_freeable+0x2ef/0x3b0 init/main.c:1074
kernel_init+0xd/0x164 init/main.c:999
ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:404
-> #1 (event_mutex){+.+.}:
__mutex_lock_common kernel/locking/mutex.c:756 [inline]
__mutex_lock+0xf7/0x13e0 kernel/locking/mutex.c:893
perf_trace_destroy+0x23/0x100 kernel/trace/trace_event_perf.c:234
_free_event+0x293/0xbb0 kernel/events/core.c:4243
free_event+0x42/0xa0 kernel/events/core.c:4270
perf_event_release_kernel+0x35c/0x880 kernel/events/core.c:4414
perf_release+0x33/0x40 kernel/events/core.c:4440
__fput+0x25e/0x710 fs/file_table.c:210
task_work_run+0x125/0x1a0 kernel/task_work.c:113
exit_task_work include/linux/task_work.h:22 [inline]
do_exit+0x9cb/0x2a20 kernel/exit.c:875
do_group_exit+0x100/0x2e0 kernel/exit.c:978
SYSC_exit_group kernel/exit.c:989 [inline]
SyS_exit_group+0x19/0x20 kernel/exit.c:987
do_syscall_64+0x19b/0x520 arch/x86/entry/common.c:292
entry_SYSCALL_64_after_hwframe+0x42/0xb7
-> #0 (&event->child_mutex){+.+.}:
lock_acquire+0x12b/0x360 kernel/locking/lockdep.c:3991
__mutex_lock_common kernel/locking/mutex.c:756 [inline]
__mutex_lock+0xf7/0x13e0 kernel/locking/mutex.c:893
perf_event_for_each_child+0x82/0x150 kernel/events/core.c:4687
_perf_ioctl kernel/events/core.c:4871 [inline]
perf_ioctl+0x53e/0x1bb0 kernel/events/core.c:4883
vfs_ioctl fs/ioctl.c:46 [inline]
file_ioctl fs/ioctl.c:500 [inline]
do_vfs_ioctl+0xabe/0x1040 fs/ioctl.c:684
SYSC_ioctl fs/ioctl.c:701 [inline]
SyS_ioctl+0x7f/0xb0 fs/ioctl.c:692
do_syscall_64+0x19b/0x520 arch/x86/entry/common.c:292
entry_SYSCALL_64_after_hwframe+0x42/0xb7
other info that might help us debug this:
Chain exists of:
&event->child_mutex --> pmus_lock --> &cpuctx_mutex
Possible unsafe locking scenario:
CPU0 CPU1
---- ----
lock(&cpuctx_mutex);
lock(pmus_lock);
lock(&cpuctx_mutex);
lock(&event->child_mutex);
*** DEADLOCK ***
1 lock held by syz-executor.3/7353:
#0: (&cpuctx_mutex){+.+.}, at: [<000000006e51dfa1>] perf_event_ctx_lock_nested+0x15a/0x2d0 kernel/events/core.c:1240
stack backtrace:
CPU: 1 PID: 7353 Comm: syz-executor.3 Not tainted 4.14.139+ #34
Call Trace:
__dump_stack lib/dump_stack.c:17 [inline]
dump_stack+0xca/0x134 lib/dump_stack.c:53
print_circular_bug.isra.0.cold+0x2dc/0x425 kernel/locking/lockdep.c:1258
check_prev_add kernel/locking/lockdep.c:1901 [inline]
check_prevs_add kernel/locking/lockdep.c:2018 [inline]
validate_chain kernel/locking/lockdep.c:2460 [inline]
__lock_acquire+0x2f5f/0x4320 kernel/locking/lockdep.c:3487
lock_acquire+0x12b/0x360 kernel/locking/lockdep.c:3991
__mutex_lock_common kernel/locking/mutex.c:756 [inline]
__mutex_lock+0xf7/0x13e0 kernel/locking/mutex.c:893
perf_event_for_each_child+0x82/0x150 kernel/events/core.c:4687
_perf_ioctl kernel/events/core.c:4871 [inline]
perf_ioctl+0x53e/0x1bb0 kernel/events/core.c:4883
vfs_ioctl fs/ioctl.c:46 [inline]
file_ioctl fs/ioctl.c:500 [inline]
do_vfs_ioctl+0xabe/0x1040 fs/ioctl.c:684
SYSC_ioctl fs/ioctl.c:701 [inline]
SyS_ioctl+0x7f/0xb0 fs/ioctl.c:692
do_syscall_64+0x19b/0x520 arch/x86/entry/common.c:292
entry_SYSCALL_64_after_hwframe+0x42/0xb7
RIP: 0033:0x459829
RSP: 002b:00007fe6bdbf5c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000459829
RDX: 0000000000000000 RSI: 0000000000002403 RDI: 0000000000000004
RBP: 000000000075bf20 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007fe6bdbf66d4
R13: 00000000004c324a R14: 00000000004d69c0 R15: 00000000ffffffff
kauditd_printk_skb: 45 callbacks suppressed
audit: type=1400 audit(1566072969.041:90152): avc: denied { map } for pid=7391 comm="syz-executor.4" path="/root/syzkaller-testdir812875195/syzkaller.q5LNvq/758/bus" dev="sda1" ino=16771 scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=unconfined_u:object_r:user_home_t:s0 tclass=file permissive=1
audit: type=1400 audit(1566072969.481:90153): avc: denied { map } for pid=7418 comm="syz-executor.4" path="/root/syzkaller-testdir812875195/syzkaller.q5LNvq/759/bus" dev="sda1" ino=16806 scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=unconfined_u:object_r:user_home_t:s0 tclass=file permissive=1
audit: type=1400 audit(1566072969.861:90154): avc: denied { map } for pid=7434 comm="syz-executor.4" path="/dev/loop0" dev="sda1" ino=2661 scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=system_u:object_r:file_t:s0 tclass=blk_file permissive=1
audit: type=1400 audit(1566072970.201:90155): avc: denied { map } for pid=7454 comm="modprobe" path="/bin/kmod" dev="sda1" ino=1440 scontext=system_u:system_r:kernel_t:s0 tcontext=system_u:object_r:file_t:s0 tclass=file permissive=1
audit: type=1400 audit(1566072970.201:90156): avc: denied { map } for pid=7454 comm="modprobe" path="/bin/kmod" dev="sda1" ino=1440 scontext=system_u:system_r:kernel_t:s0 tcontext=system_u:object_r:file_t:s0 tclass=file permissive=1
audit: type=1400 audit(1566072970.201:90157): avc: denied { map } for pid=7454 comm="modprobe" path="/lib/x86_64-linux-gnu/ld-2.13.so" dev="sda1" ino=2668 scontext=system_u:system_r:kernel_t:s0 tcontext=system_u:object_r:file_t:s0 tclass=file permissive=1
audit: type=1400 audit(1566072970.201:90158): avc: denied { map } for pid=7454 comm="modprobe" path="/lib/x86_64-linux-gnu/ld-2.13.so" dev="sda1" ino=2668 scontext=system_u:system_r:kernel_t:s0 tcontext=system_u:object_r:file_t:s0 tclass=file permissive=1
audit: type=1400 audit(1566072970.211:90159): avc: denied { map } for pid=7454 comm="modprobe" path="/etc/ld.so.cache" dev="sda1" ino=2503 scontext=system_u:system_r:kernel_t:s0 tcontext=system_u:object_r:file_t:s0 tclass=file permissive=1
audit: type=1400 audit(1566072970.211:90160): avc: denied { map } for pid=7454 comm="modprobe" path="/lib/x86_64-linux-gnu/libkmod.so.2.1.3" dev="sda1" ino=2811 scontext=system_u:system_r:kernel_t:s0 tcontext=system_u:object_r:file_t:s0 tclass=file permissive=1
audit: type=1400 audit(1566072970.211:90161): avc: denied { map } for pid=7454 comm="modprobe" path="/lib/x86_64-linux-gnu/libkmod.so.2.1.3" dev="sda1" ino=2811 scontext=system_u:system_r:kernel_t:s0 tcontext=system_u:object_r:file_t:s0 tclass=file permissive=1
| Time | Kernel | Commit | Syzkaller | Config | Log | Report | Syz repro | C repro | VM info | Assets (help?) | Manager | Title |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 2019/08/17 20:16 | android-4.14 | 5d8bfdf81cde | 55bf8926 | .config | console log | report | ci-android-414-kasan-gce-root | |||||
| 2019/04/08 08:00 | android-4.14 | 171fc237b3cb | c34fde03 | .config | console log | report | ci-android-414-kasan-gce-root | |||||
| 2019/04/07 20:21 | android-4.14 | 171fc237b3cb | c34fde03 | .config | console log | report | ci-android-414-kasan-gce-root | |||||
| 2019/01/30 13:51 | android-4.14 | 63d1657d00e0 | aa432daf | .config | console log | report | ci-android-414-kasan-gce-root | |||||
| 2018/12/27 18:10 | android-4.14 | 815e34f802d8 | 43cf01dd | .config | console log | report | ci-android-414-kasan-gce-root | |||||
| 2018/12/27 10:06 | android-4.14 | 815e34f802d8 | e747ec98 | .config | console log | report | ci-android-414-kasan-gce-root | |||||
| 2018/12/15 07:13 | android-4.14 | 4ee7197c44f6 | 7624ddd6 | .config | console log | report | ci-android-414-kasan-gce-root | |||||
| 2018/11/29 08:29 | android-4.14 | 9ff6ab2fbc00 | 4b6d14f2 | .config | console log | report | ci-android-414-kasan-gce-root | |||||
| 2018/10/09 10:45 | android-4.14 | d33692e8014d | 8b311eaf | .config | console log | report | ci-android-414-kasan-gce-root |