possible deadlock in ftrace_profile_set_filter
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syzbot
Apr 16, 2019, 4:57:07 PM4/16/19
to syzkaller...@googlegroups.com
Hello,
syzbot found the following crash on:
HEAD commit: 1ec8f1f0 Linux 4.14.111
git tree: linux-4.14.y
console output: https://syzkaller.appspot.com/x/log.txt?x=14e62a67200000
kernel config: https://syzkaller.appspot.com/x/.config?x=fdadf290ea9fc6f9
dashboard link: https://syzkaller.appspot.com/bug?extid=ca6c4944f8e1acff7742
compiler: gcc (GCC) 9.0.0 20181231 (experimental)
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=121235b7200000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=125c55d3200000
IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: syzbot+ca6c49...@syzkaller.appspotmail.com
random: sshd: uninitialized urandom read (32 bytes read)
random: sshd: uninitialized urandom read (32 bytes read)
random: sshd: uninitialized urandom read (32 bytes read)
audit: type=1400 audit(1555446478.905:36): avc: denied { map } for
pid=7196 comm="syz-executor119" path="/root/syz-executor119668547"
dev="sda1" ino=16484 scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023
tcontext=unconfined_u:object_r:user_home_t:s0 tclass=file permissive=1
======================================================
WARNING: possible circular locking dependency detected
4.14.111 #1 Not tainted
------------------------------------------------------
syz-executor119/7196 is trying to acquire lock:
(event_mutex){+.+.}, at: [<ffffffff81636f1a>]
ftrace_profile_set_filter+0x6a/0x1d0 kernel/trace/trace_events_filter.c:2268
but task is already holding lock:
(&cpuctx_mutex){+.+.}, at: [<ffffffff816bb020>]
perf_event_ctx_lock_nested+0x150/0x2c0 kernel/events/core.c:1235
which lock already depends on the new lock.
the existing dependency chain (in reverse order) is:
-> #4 (&cpuctx_mutex){+.+.}:
lock_acquire+0x16f/0x430 kernel/locking/lockdep.c:3994
__mutex_lock_common kernel/locking/mutex.c:756 [inline]
__mutex_lock+0xe8/0x1470 kernel/locking/mutex.c:893
mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:908
perf_event_init_cpu+0xc2/0x170 kernel/events/core.c:11221
perf_event_init+0x2d8/0x31a kernel/events/core.c:11268
start_kernel+0x3b9/0x700 init/main.c:621
x86_64_start_reservations+0x29/0x2b arch/x86/kernel/head64.c:380
x86_64_start_kernel+0x77/0x7b arch/x86/kernel/head64.c:361
secondary_startup_64+0xa5/0xb0 arch/x86/kernel/head_64.S:240
-> #3 (pmus_lock){+.+.}:
lock_acquire+0x16f/0x430 kernel/locking/lockdep.c:3994
__mutex_lock_common kernel/locking/mutex.c:756 [inline]
__mutex_lock+0xe8/0x1470 kernel/locking/mutex.c:893
mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:908
perf_event_init_cpu+0x2f/0x170 kernel/events/core.c:11215
cpuhp_invoke_callback+0x1ec/0x1ac0 kernel/cpu.c:184
cpuhp_up_callbacks kernel/cpu.c:572 [inline]
_cpu_up+0x228/0x530 kernel/cpu.c:1134
do_cpu_up+0x121/0x150 kernel/cpu.c:1169
cpu_up+0x1b/0x20 kernel/cpu.c:1177
smp_init+0x157/0x173 kernel/smp.c:578
kernel_init_freeable+0x30e/0x538 init/main.c:1067
kernel_init+0x12/0x162 init/main.c:999
ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:402
-> #2 (cpu_hotplug_lock.rw_sem){++++}:
lock_acquire+0x16f/0x430 kernel/locking/lockdep.c:3994
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+0x3d/0xc0 kernel/cpu.c:295
static_key_slow_inc+0x13/0x30 kernel/jump_label.c:123
tracepoint_add_func kernel/tracepoint.c:223 [inline]
tracepoint_probe_register_prio+0x4dc/0x6d0 kernel/tracepoint.c:283
tracepoint_probe_register+0x2b/0x40 kernel/tracepoint.c:304
trace_event_reg+0x277/0x330 kernel/trace/trace_events.c:305
perf_trace_event_reg kernel/trace/trace_event_perf.c:122 [inline]
perf_trace_event_init kernel/trace/trace_event_perf.c:197 [inline]
perf_trace_init+0x450/0xaa0 kernel/trace/trace_event_perf.c:221
perf_tp_event_init+0x7d/0xf0 kernel/events/core.c:8104
perf_try_init_event+0x170/0x210 kernel/events/core.c:9340
perf_init_event kernel/events/core.c:9378 [inline]
perf_event_alloc.part.0+0xd48/0x2540 kernel/events/core.c:9638
perf_event_alloc kernel/events/core.c:9991 [inline]
SYSC_perf_event_open+0xa2d/0x24c0 kernel/events/core.c:10095
SyS_perf_event_open+0x34/0x40 kernel/events/core.c:9981
do_syscall_64+0x1eb/0x630 arch/x86/entry/common.c:289
entry_SYSCALL_64_after_hwframe+0x42/0xb7
-> #1 (tracepoints_mutex){+.+.}:
lock_acquire+0x16f/0x430 kernel/locking/lockdep.c:3994
__mutex_lock_common kernel/locking/mutex.c:756 [inline]
__mutex_lock+0xe8/0x1470 kernel/locking/mutex.c:893
mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:908
tracepoint_probe_register_prio+0x36/0x6d0 kernel/tracepoint.c:279
tracepoint_probe_register+0x2b/0x40 kernel/tracepoint.c:304
trace_event_reg+0x277/0x330 kernel/trace/trace_events.c:305
perf_trace_event_reg kernel/trace/trace_event_perf.c:122 [inline]
perf_trace_event_init kernel/trace/trace_event_perf.c:197 [inline]
perf_trace_init+0x450/0xaa0 kernel/trace/trace_event_perf.c:221
perf_tp_event_init+0x7d/0xf0 kernel/events/core.c:8104
perf_try_init_event+0x170/0x210 kernel/events/core.c:9340
perf_init_event kernel/events/core.c:9378 [inline]
perf_event_alloc.part.0+0xd48/0x2540 kernel/events/core.c:9638
perf_event_alloc kernel/events/core.c:9991 [inline]
SYSC_perf_event_open+0xa2d/0x24c0 kernel/events/core.c:10095
SyS_perf_event_open+0x34/0x40 kernel/events/core.c:9981
do_syscall_64+0x1eb/0x630 arch/x86/entry/common.c:289
entry_SYSCALL_64_after_hwframe+0x42/0xb7
-> #0 (event_mutex){+.+.}:
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+0x2c89/0x45e0 kernel/locking/lockdep.c:3487
lock_acquire+0x16f/0x430 kernel/locking/lockdep.c:3994
__mutex_lock_common kernel/locking/mutex.c:756 [inline]
__mutex_lock+0xe8/0x1470 kernel/locking/mutex.c:893
mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:908
ftrace_profile_set_filter+0x6a/0x1d0
kernel/trace/trace_events_filter.c:2268
perf_event_set_filter+0xa54/0xd10 kernel/events/core.c:8690
_perf_ioctl kernel/events/core.c:4841 [inline]
perf_ioctl+0x53c/0xcb0 kernel/events/core.c:4878
vfs_ioctl fs/ioctl.c:46 [inline]
file_ioctl fs/ioctl.c:500 [inline]
do_vfs_ioctl+0x7b9/0x1070 fs/ioctl.c:684
SYSC_ioctl fs/ioctl.c:701 [inline]
SyS_ioctl+0x8f/0xc0 fs/ioctl.c:692
do_syscall_64+0x1eb/0x630 arch/x86/entry/common.c:289
entry_SYSCALL_64_after_hwframe+0x42/0xb7
other info that might help us debug this:
Chain exists of:
event_mutex --> pmus_lock --> &cpuctx_mutex
Possible unsafe locking scenario:
CPU0 CPU1
---- ----
lock(&cpuctx_mutex);
lock(pmus_lock);
lock(&cpuctx_mutex);
lock(event_mutex);
*** DEADLOCK ***
1 lock held by syz-executor119/7196:
#0: (&cpuctx_mutex){+.+.}, at: [<ffffffff816bb020>]
perf_event_ctx_lock_nested+0x150/0x2c0 kernel/events/core.c:1235
stack backtrace:
CPU: 1 PID: 7196 Comm: syz-executor119 Not tainted 4.14.111 #1
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS
Google 01/01/2011
Call Trace:
__dump_stack lib/dump_stack.c:17 [inline]
dump_stack+0x138/0x19c lib/dump_stack.c:53
print_circular_bug.isra.0.cold+0x1cc/0x28f 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+0x2c89/0x45e0 kernel/locking/lockdep.c:3487
lock_acquire+0x16f/0x430 kernel/locking/lockdep.c:3994
__mutex_lock_common kernel/locking/mutex.c:756 [inline]
__mutex_lock+0xe8/0x1470 kernel/locking/mutex.c:893
mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:908
ftrace_profile_set_filter+0x6a/0x1d0
kernel/trace/trace_events_filter.c:2268
perf_event_set_filter+0xa54/0xd10 kernel/events/core.c:8690
_perf_ioctl kernel/events/core.c:4841 [inline]
perf_ioctl+0x53c/0xcb0 kernel/events/core.c:4878
vfs_ioctl fs/ioctl.c:46 [inline]
file_ioctl fs/ioctl.c:500 [inline]
do_vfs_ioctl+0x7b9/0x1070 fs/ioctl.c:684
SYSC_ioctl fs/ioctl.c:701 [inline]
SyS_ioctl+0x8f/0xc0 fs/ioctl.c:692
do_syscall_64+0x1eb/0x630 arch/x86/entry/common.c:289
entry_SYSCALL_64_after_hwframe+0x42/0xb7
RIP: 0033:0x440249
RSP: 002b:00007fff30a35f08 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00000000004002c8 RCX: 0000000000440249
RDX: 0000000020000000 RSI: 0000000040082406 RDI: 0000000000000003
RBP: 00000000006ca018 R08: 0000000000000000 R09: 00000000004002c8
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000401ad0
R13: 0000000000401b60 R14: 0000000000000000 R15: 0000000000000000
---
This bug is generated by a bot. It may contain errors.
See https://goo.gl/tpsmEJ for more information about syzbot.
syzbot engineers can be reached at syzk...@googlegroups.com.
syzbot will keep track of this bug report. See:
https://goo.gl/tpsmEJ#status for how to communicate with syzbot.
syzbot can test patches for this bug, for details see:
https://goo.gl/tpsmEJ#testing-patches
syzbot found the following crash on:
HEAD commit: 1ec8f1f0 Linux 4.14.111
git tree: linux-4.14.y
console output: https://syzkaller.appspot.com/x/log.txt?x=14e62a67200000
kernel config: https://syzkaller.appspot.com/x/.config?x=fdadf290ea9fc6f9
dashboard link: https://syzkaller.appspot.com/bug?extid=ca6c4944f8e1acff7742
compiler: gcc (GCC) 9.0.0 20181231 (experimental)
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=121235b7200000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=125c55d3200000
IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: syzbot+ca6c49...@syzkaller.appspotmail.com
random: sshd: uninitialized urandom read (32 bytes read)
random: sshd: uninitialized urandom read (32 bytes read)
random: sshd: uninitialized urandom read (32 bytes read)
audit: type=1400 audit(1555446478.905:36): avc: denied { map } for
pid=7196 comm="syz-executor119" path="/root/syz-executor119668547"
dev="sda1" ino=16484 scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023
tcontext=unconfined_u:object_r:user_home_t:s0 tclass=file permissive=1
======================================================
WARNING: possible circular locking dependency detected
4.14.111 #1 Not tainted
------------------------------------------------------
syz-executor119/7196 is trying to acquire lock:
(event_mutex){+.+.}, at: [<ffffffff81636f1a>]
ftrace_profile_set_filter+0x6a/0x1d0 kernel/trace/trace_events_filter.c:2268
but task is already holding lock:
(&cpuctx_mutex){+.+.}, at: [<ffffffff816bb020>]
perf_event_ctx_lock_nested+0x150/0x2c0 kernel/events/core.c:1235
which lock already depends on the new lock.
the existing dependency chain (in reverse order) is:
-> #4 (&cpuctx_mutex){+.+.}:
lock_acquire+0x16f/0x430 kernel/locking/lockdep.c:3994
__mutex_lock_common kernel/locking/mutex.c:756 [inline]
__mutex_lock+0xe8/0x1470 kernel/locking/mutex.c:893
mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:908
perf_event_init_cpu+0xc2/0x170 kernel/events/core.c:11221
perf_event_init+0x2d8/0x31a kernel/events/core.c:11268
start_kernel+0x3b9/0x700 init/main.c:621
x86_64_start_reservations+0x29/0x2b arch/x86/kernel/head64.c:380
x86_64_start_kernel+0x77/0x7b arch/x86/kernel/head64.c:361
secondary_startup_64+0xa5/0xb0 arch/x86/kernel/head_64.S:240
-> #3 (pmus_lock){+.+.}:
lock_acquire+0x16f/0x430 kernel/locking/lockdep.c:3994
__mutex_lock_common kernel/locking/mutex.c:756 [inline]
__mutex_lock+0xe8/0x1470 kernel/locking/mutex.c:893
mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:908
perf_event_init_cpu+0x2f/0x170 kernel/events/core.c:11215
cpuhp_invoke_callback+0x1ec/0x1ac0 kernel/cpu.c:184
cpuhp_up_callbacks kernel/cpu.c:572 [inline]
_cpu_up+0x228/0x530 kernel/cpu.c:1134
do_cpu_up+0x121/0x150 kernel/cpu.c:1169
cpu_up+0x1b/0x20 kernel/cpu.c:1177
smp_init+0x157/0x173 kernel/smp.c:578
kernel_init_freeable+0x30e/0x538 init/main.c:1067
kernel_init+0x12/0x162 init/main.c:999
ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:402
-> #2 (cpu_hotplug_lock.rw_sem){++++}:
lock_acquire+0x16f/0x430 kernel/locking/lockdep.c:3994
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+0x3d/0xc0 kernel/cpu.c:295
static_key_slow_inc+0x13/0x30 kernel/jump_label.c:123
tracepoint_add_func kernel/tracepoint.c:223 [inline]
tracepoint_probe_register_prio+0x4dc/0x6d0 kernel/tracepoint.c:283
tracepoint_probe_register+0x2b/0x40 kernel/tracepoint.c:304
trace_event_reg+0x277/0x330 kernel/trace/trace_events.c:305
perf_trace_event_reg kernel/trace/trace_event_perf.c:122 [inline]
perf_trace_event_init kernel/trace/trace_event_perf.c:197 [inline]
perf_trace_init+0x450/0xaa0 kernel/trace/trace_event_perf.c:221
perf_tp_event_init+0x7d/0xf0 kernel/events/core.c:8104
perf_try_init_event+0x170/0x210 kernel/events/core.c:9340
perf_init_event kernel/events/core.c:9378 [inline]
perf_event_alloc.part.0+0xd48/0x2540 kernel/events/core.c:9638
perf_event_alloc kernel/events/core.c:9991 [inline]
SYSC_perf_event_open+0xa2d/0x24c0 kernel/events/core.c:10095
SyS_perf_event_open+0x34/0x40 kernel/events/core.c:9981
do_syscall_64+0x1eb/0x630 arch/x86/entry/common.c:289
entry_SYSCALL_64_after_hwframe+0x42/0xb7
-> #1 (tracepoints_mutex){+.+.}:
lock_acquire+0x16f/0x430 kernel/locking/lockdep.c:3994
__mutex_lock_common kernel/locking/mutex.c:756 [inline]
__mutex_lock+0xe8/0x1470 kernel/locking/mutex.c:893
mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:908
tracepoint_probe_register_prio+0x36/0x6d0 kernel/tracepoint.c:279
tracepoint_probe_register+0x2b/0x40 kernel/tracepoint.c:304
trace_event_reg+0x277/0x330 kernel/trace/trace_events.c:305
perf_trace_event_reg kernel/trace/trace_event_perf.c:122 [inline]
perf_trace_event_init kernel/trace/trace_event_perf.c:197 [inline]
perf_trace_init+0x450/0xaa0 kernel/trace/trace_event_perf.c:221
perf_tp_event_init+0x7d/0xf0 kernel/events/core.c:8104
perf_try_init_event+0x170/0x210 kernel/events/core.c:9340
perf_init_event kernel/events/core.c:9378 [inline]
perf_event_alloc.part.0+0xd48/0x2540 kernel/events/core.c:9638
perf_event_alloc kernel/events/core.c:9991 [inline]
SYSC_perf_event_open+0xa2d/0x24c0 kernel/events/core.c:10095
SyS_perf_event_open+0x34/0x40 kernel/events/core.c:9981
do_syscall_64+0x1eb/0x630 arch/x86/entry/common.c:289
entry_SYSCALL_64_after_hwframe+0x42/0xb7
-> #0 (event_mutex){+.+.}:
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+0x2c89/0x45e0 kernel/locking/lockdep.c:3487
lock_acquire+0x16f/0x430 kernel/locking/lockdep.c:3994
__mutex_lock_common kernel/locking/mutex.c:756 [inline]
__mutex_lock+0xe8/0x1470 kernel/locking/mutex.c:893
mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:908
ftrace_profile_set_filter+0x6a/0x1d0
kernel/trace/trace_events_filter.c:2268
perf_event_set_filter+0xa54/0xd10 kernel/events/core.c:8690
_perf_ioctl kernel/events/core.c:4841 [inline]
perf_ioctl+0x53c/0xcb0 kernel/events/core.c:4878
vfs_ioctl fs/ioctl.c:46 [inline]
file_ioctl fs/ioctl.c:500 [inline]
do_vfs_ioctl+0x7b9/0x1070 fs/ioctl.c:684
SYSC_ioctl fs/ioctl.c:701 [inline]
SyS_ioctl+0x8f/0xc0 fs/ioctl.c:692
do_syscall_64+0x1eb/0x630 arch/x86/entry/common.c:289
entry_SYSCALL_64_after_hwframe+0x42/0xb7
other info that might help us debug this:
Chain exists of:
event_mutex --> pmus_lock --> &cpuctx_mutex
Possible unsafe locking scenario:
CPU0 CPU1
---- ----
lock(&cpuctx_mutex);
lock(pmus_lock);
lock(&cpuctx_mutex);
lock(event_mutex);
*** DEADLOCK ***
1 lock held by syz-executor119/7196:
#0: (&cpuctx_mutex){+.+.}, at: [<ffffffff816bb020>]
perf_event_ctx_lock_nested+0x150/0x2c0 kernel/events/core.c:1235
stack backtrace:
CPU: 1 PID: 7196 Comm: syz-executor119 Not tainted 4.14.111 #1
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS
Google 01/01/2011
Call Trace:
__dump_stack lib/dump_stack.c:17 [inline]
dump_stack+0x138/0x19c lib/dump_stack.c:53
print_circular_bug.isra.0.cold+0x1cc/0x28f 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+0x2c89/0x45e0 kernel/locking/lockdep.c:3487
lock_acquire+0x16f/0x430 kernel/locking/lockdep.c:3994
__mutex_lock_common kernel/locking/mutex.c:756 [inline]
__mutex_lock+0xe8/0x1470 kernel/locking/mutex.c:893
mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:908
ftrace_profile_set_filter+0x6a/0x1d0
kernel/trace/trace_events_filter.c:2268
perf_event_set_filter+0xa54/0xd10 kernel/events/core.c:8690
_perf_ioctl kernel/events/core.c:4841 [inline]
perf_ioctl+0x53c/0xcb0 kernel/events/core.c:4878
vfs_ioctl fs/ioctl.c:46 [inline]
file_ioctl fs/ioctl.c:500 [inline]
do_vfs_ioctl+0x7b9/0x1070 fs/ioctl.c:684
SYSC_ioctl fs/ioctl.c:701 [inline]
SyS_ioctl+0x8f/0xc0 fs/ioctl.c:692
do_syscall_64+0x1eb/0x630 arch/x86/entry/common.c:289
entry_SYSCALL_64_after_hwframe+0x42/0xb7
RIP: 0033:0x440249
RSP: 002b:00007fff30a35f08 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00000000004002c8 RCX: 0000000000440249
RDX: 0000000020000000 RSI: 0000000040082406 RDI: 0000000000000003
RBP: 00000000006ca018 R08: 0000000000000000 R09: 00000000004002c8
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000401ad0
R13: 0000000000401b60 R14: 0000000000000000 R15: 0000000000000000
---
This bug is generated by a bot. It may contain errors.
See https://goo.gl/tpsmEJ for more information about syzbot.
syzbot engineers can be reached at syzk...@googlegroups.com.
syzbot will keep track of this bug report. See:
https://goo.gl/tpsmEJ#status for how to communicate with syzbot.
syzbot can test patches for this bug, for details see:
https://goo.gl/tpsmEJ#testing-patches
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