[v6.1] possible deadlock in __mmap_lock_do_trace_acquire_returned

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syzbot

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Apr 13, 2024, 2:55:27 AMApr 13
to syzkaller...@googlegroups.com
Hello,

syzbot found the following issue on:

HEAD commit: bf1e3b1cb1e0 Linux 6.1.85
git tree: linux-6.1.y
console output: https://syzkaller.appspot.com/x/log.txt?x=17c032db180000
kernel config: https://syzkaller.appspot.com/x/.config?x=d3e21b90946dbbab
dashboard link: https://syzkaller.appspot.com/bug?extid=351f700c0b4cbf13a0b2
compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40

Unfortunately, I don't have any reproducer for this issue yet.

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/75265c862e54/disk-bf1e3b1c.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/1d22ca40ea90/vmlinux-bf1e3b1c.xz
kernel image: https://storage.googleapis.com/syzbot-assets/a5fcb5ebd870/bzImage-bf1e3b1c.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+351f70...@syzkaller.appspotmail.com

======================================================
WARNING: possible circular locking dependency detected
6.1.85-syzkaller #0 Not tainted
------------------------------------------------------
syz-executor.0/8302 is trying to acquire lock:
ffff8880b9935e90 (lock#10){+.+.}-{2:2}, at: local_lock_acquire include/linux/local_lock_internal.h:29 [inline]
ffff8880b9935e90 (lock#10){+.+.}-{2:2}, at: __mmap_lock_do_trace_acquire_returned+0x84/0x670 mm/mmap_lock.c:237

but task is already holding lock:
ffff8880b993a258 (&pool->lock){-.-.}-{2:2}, at: __queue_work+0x58c/0xf90

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #3 (&pool->lock){-.-.}-{2:2}:
lock_acquire+0x1f8/0x5a0 kernel/locking/lockdep.c:5662
__raw_spin_lock include/linux/spinlock_api_smp.h:133 [inline]
_raw_spin_lock+0x2a/0x40 kernel/locking/spinlock.c:154
__queue_work+0x58c/0xf90
queue_work_on+0x14b/0x250 kernel/workqueue.c:1548
queue_work include/linux/workqueue.h:512 [inline]
schedule_work include/linux/workqueue.h:573 [inline]
aio_poll_wake+0x1a2/0x9a0 fs/aio.c:1821
__wake_up_common+0x2a0/0x4e0 kernel/sched/wait.c:107
__wake_up_common_lock kernel/sched/wait.c:138 [inline]
__wake_up+0x11a/0x1c0 kernel/sched/wait.c:160
do_signalfd4+0x2e6/0x350 fs/signalfd.c:295
__do_sys_signalfd4 fs/signalfd.c:311 [inline]
__se_sys_signalfd4 fs/signalfd.c:302 [inline]
__x64_sys_signalfd4+0x170/0x1b0 fs/signalfd.c:302
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81
entry_SYSCALL_64_after_hwframe+0x68/0xd2

-> #2 (&sighand->signalfd_wqh){-.-.}-{2:2}:
lock_acquire+0x1f8/0x5a0 kernel/locking/lockdep.c:5662
__raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
_raw_spin_lock_irqsave+0xd1/0x120 kernel/locking/spinlock.c:162
__wake_up_common_lock kernel/sched/wait.c:137 [inline]
__wake_up+0xfd/0x1c0 kernel/sched/wait.c:160
signalfd_notify include/linux/signalfd.h:22 [inline]
__send_signal_locked+0xbdc/0xdc0 kernel/signal.c:1177
do_notify_parent+0xe2b/0x1100 kernel/signal.c:2120
exit_notify kernel/exit.c:744 [inline]
do_exit+0x172e/0x26a0 kernel/exit.c:889
do_group_exit+0x202/0x2b0 kernel/exit.c:1019
__do_sys_exit_group kernel/exit.c:1030 [inline]
__se_sys_exit_group kernel/exit.c:1028 [inline]
__x64_sys_exit_group+0x3b/0x40 kernel/exit.c:1028
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81
entry_SYSCALL_64_after_hwframe+0x68/0xd2

-> #1 (&sighand->siglock){-.-.}-{2:2}:
lock_acquire+0x1f8/0x5a0 kernel/locking/lockdep.c:5662
__raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
_raw_spin_lock_irqsave+0xd1/0x120 kernel/locking/spinlock.c:162
__lock_task_sighand+0x145/0x2d0 kernel/signal.c:1410
lock_task_sighand include/linux/sched/signal.h:745 [inline]
do_send_sig_info kernel/signal.c:1299 [inline]
group_send_sig_info+0x26c/0x300 kernel/signal.c:1448
bpf_send_signal_common+0x2d8/0x420 kernel/trace/bpf_trace.c:882
____bpf_send_signal_thread kernel/trace/bpf_trace.c:899 [inline]
bpf_send_signal_thread+0x12/0x20 kernel/trace/bpf_trace.c:897
0xffffffffa0000962
bpf_dispatcher_nop_func include/linux/bpf.h:989 [inline]
__bpf_prog_run include/linux/filter.h:603 [inline]
bpf_prog_run include/linux/filter.h:610 [inline]
__bpf_trace_run kernel/trace/bpf_trace.c:2273 [inline]
bpf_trace_run4+0x253/0x470 kernel/trace/bpf_trace.c:2314
trace_mmap_lock_acquire_returned include/trace/events/mmap_lock.h:52 [inline]
__mmap_lock_do_trace_acquire_returned+0x5e3/0x670 mm/mmap_lock.c:237
__mmap_lock_trace_acquire_returned include/linux/mmap_lock.h:36 [inline]
mmap_write_lock_killable include/linux/mmap_lock.h:88 [inline]
__do_sys_mremap mm/mremap.c:943 [inline]
__se_sys_mremap+0x1998/0x1b20 mm/mremap.c:889
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81
entry_SYSCALL_64_after_hwframe+0x68/0xd2

-> #0 (lock#10){+.+.}-{2:2}:
check_prev_add kernel/locking/lockdep.c:3090 [inline]
check_prevs_add kernel/locking/lockdep.c:3209 [inline]
validate_chain+0x1661/0x5950 kernel/locking/lockdep.c:3825
__lock_acquire+0x125b/0x1f80 kernel/locking/lockdep.c:5049
lock_acquire+0x1f8/0x5a0 kernel/locking/lockdep.c:5662
local_lock_acquire include/linux/local_lock_internal.h:29 [inline]
__mmap_lock_do_trace_acquire_returned+0x9d/0x670 mm/mmap_lock.c:237
__mmap_lock_trace_acquire_returned include/linux/mmap_lock.h:36 [inline]
mmap_read_trylock include/linux/mmap_lock.h:137 [inline]
stack_map_get_build_id_offset+0x99e/0x9c0 kernel/bpf/stackmap.c:144
__bpf_get_stack+0x495/0x570 kernel/bpf/stackmap.c:452
____bpf_get_stack_raw_tp kernel/trace/bpf_trace.c:1877 [inline]
bpf_get_stack_raw_tp+0x1b2/0x220 kernel/trace/bpf_trace.c:1867
bpf_prog_e6cf5f9c69743609+0x3a/0x3e
bpf_dispatcher_nop_func include/linux/bpf.h:989 [inline]
__bpf_prog_run include/linux/filter.h:603 [inline]
bpf_prog_run include/linux/filter.h:610 [inline]
__bpf_trace_run kernel/trace/bpf_trace.c:2273 [inline]
bpf_trace_run3+0x231/0x440 kernel/trace/bpf_trace.c:2313
trace_workqueue_queue_work include/trace/events/workqueue.h:23 [inline]
__queue_work+0xeeb/0xf90 kernel/workqueue.c:1500
queue_work_on+0x14b/0x250 kernel/workqueue.c:1548
bpf_prog_load+0xda2/0x1bb0 kernel/bpf/syscall.c:2679
__sys_bpf+0x382/0x6c0 kernel/bpf/syscall.c:5005
__do_sys_bpf kernel/bpf/syscall.c:5109 [inline]
__se_sys_bpf kernel/bpf/syscall.c:5107 [inline]
__x64_sys_bpf+0x78/0x90 kernel/bpf/syscall.c:5107
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81
entry_SYSCALL_64_after_hwframe+0x68/0xd2

other info that might help us debug this:

Chain exists of:
lock#10 --> &sighand->signalfd_wqh --> &pool->lock

Possible unsafe locking scenario:

CPU0 CPU1
---- ----
lock(&pool->lock);
lock(&sighand->signalfd_wqh);
lock(&pool->lock);
lock(lock#10);

*** DEADLOCK ***

4 locks held by syz-executor.0/8302:
#0: ffffffff8d12ac40 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:350 [inline]
#0: ffffffff8d12ac40 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:791 [inline]
#0: ffffffff8d12ac40 (rcu_read_lock){....}-{1:2}, at: __queue_work+0xe5/0xf90 kernel/workqueue.c:1443
#1: ffff8880b993a258 (&pool->lock){-.-.}-{2:2}, at: __queue_work+0x58c/0xf90
#2: ffffffff8d12ac40 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:350 [inline]
#2: ffffffff8d12ac40 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:791 [inline]
#2: ffffffff8d12ac40 (rcu_read_lock){....}-{1:2}, at: __bpf_trace_run kernel/trace/bpf_trace.c:2272 [inline]
#2: ffffffff8d12ac40 (rcu_read_lock){....}-{1:2}, at: bpf_trace_run3+0x146/0x440 kernel/trace/bpf_trace.c:2313
#3: ffff888029a1f1d8 (&mm->mmap_lock){++++}-{3:3}, at: mmap_read_trylock include/linux/mmap_lock.h:136 [inline]
#3: ffff888029a1f1d8 (&mm->mmap_lock){++++}-{3:3}, at: stack_map_get_build_id_offset+0x232/0x9c0 kernel/bpf/stackmap.c:144

stack backtrace:
CPU: 1 PID: 8302 Comm: syz-executor.0 Not tainted 6.1.85-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0x1e3/0x2cb lib/dump_stack.c:106
check_noncircular+0x2fa/0x3b0 kernel/locking/lockdep.c:2170
check_prev_add kernel/locking/lockdep.c:3090 [inline]
check_prevs_add kernel/locking/lockdep.c:3209 [inline]
validate_chain+0x1661/0x5950 kernel/locking/lockdep.c:3825
__lock_acquire+0x125b/0x1f80 kernel/locking/lockdep.c:5049
lock_acquire+0x1f8/0x5a0 kernel/locking/lockdep.c:5662
local_lock_acquire include/linux/local_lock_internal.h:29 [inline]
__mmap_lock_do_trace_acquire_returned+0x9d/0x670 mm/mmap_lock.c:237
__mmap_lock_trace_acquire_returned include/linux/mmap_lock.h:36 [inline]
mmap_read_trylock include/linux/mmap_lock.h:137 [inline]
stack_map_get_build_id_offset+0x99e/0x9c0 kernel/bpf/stackmap.c:144
__bpf_get_stack+0x495/0x570 kernel/bpf/stackmap.c:452
____bpf_get_stack_raw_tp kernel/trace/bpf_trace.c:1877 [inline]
bpf_get_stack_raw_tp+0x1b2/0x220 kernel/trace/bpf_trace.c:1867
bpf_prog_e6cf5f9c69743609+0x3a/0x3e
bpf_dispatcher_nop_func include/linux/bpf.h:989 [inline]
__bpf_prog_run include/linux/filter.h:603 [inline]
bpf_prog_run include/linux/filter.h:610 [inline]
__bpf_trace_run kernel/trace/bpf_trace.c:2273 [inline]
bpf_trace_run3+0x231/0x440 kernel/trace/bpf_trace.c:2313
trace_workqueue_queue_work include/trace/events/workqueue.h:23 [inline]
__queue_work+0xeeb/0xf90 kernel/workqueue.c:1500
queue_work_on+0x14b/0x250 kernel/workqueue.c:1548
bpf_prog_load+0xda2/0x1bb0 kernel/bpf/syscall.c:2679
__sys_bpf+0x382/0x6c0 kernel/bpf/syscall.c:5005
__do_sys_bpf kernel/bpf/syscall.c:5109 [inline]
__se_sys_bpf kernel/bpf/syscall.c:5107 [inline]
__x64_sys_bpf+0x78/0x90 kernel/bpf/syscall.c:5107
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f6b3347de69
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 20 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f6b342c90c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000141
RAX: ffffffffffffffda RBX: 00007f6b335abf80 RCX: 00007f6b3347de69
RDX: 0000000000000090 RSI: 00000000200000c0 RDI: 0000000000000005
RBP: 00007f6b334ca47a R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000000b R14: 00007f6b335abf80 R15: 00007ffda166c1a8
</TASK>
loop0: detected capacity change from 0 to 512
EXT4-fs (loop0): filesystem is read-only
EXT4-fs (loop0): ext4_check_descriptors: Block bitmap for group 0 overlaps block group descriptors
EXT4-fs (loop0): filesystem is read-only
EXT4-fs (loop0): orphan cleanup on readonly fs
EXT4-fs error (device loop0): ext4_validate_block_bitmap:438: comm syz-executor.0: bg 0: block 64: padding at end of block bitmap is not set
EXT4-fs error (device loop0) in ext4_mb_clear_bb:6168: Corrupt filesystem
EXT4-fs (loop0): 1 orphan inode deleted
EXT4-fs (loop0): mounted filesystem without journal. Quota mode: none.


---
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syzbot

unread,
Apr 14, 2024, 11:45:32 AMApr 14
to syzkaller...@googlegroups.com
syzbot has found a reproducer for the following issue on:

HEAD commit: cd5d98c0556c Linux 6.1.86
git tree: linux-6.1.y
console output: https://syzkaller.appspot.com/x/log.txt?x=1245ca57180000
kernel config: https://syzkaller.appspot.com/x/.config?x=1002eed7bd96ee12
dashboard link: https://syzkaller.appspot.com/bug?extid=351f700c0b4cbf13a0b2
compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=15dcd74d180000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=175423d5180000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/1497cbd9943e/disk-cd5d98c0.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/9f947b67d7b1/vmlinux-cd5d98c0.xz
kernel image: https://storage.googleapis.com/syzbot-assets/92c97ada9d02/bzImage-cd5d98c0.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+351f70...@syzkaller.appspotmail.com

======================================================
WARNING: possible circular locking dependency detected
6.1.86-syzkaller #0 Not tainted
------------------------------------------------------
syz-executor271/3685 is trying to acquire lock:
ffff8880b9835e90 (lock#9){+.+.}-{2:2}, at: local_lock_acquire include/linux/local_lock_internal.h:29 [inline]
ffff8880b9835e90 (lock#9){+.+.}-{2:2}, at: __mmap_lock_do_trace_acquire_returned+0x84/0x670 mm/mmap_lock.c:237

but task is already holding lock:
ffff8880b983aa18 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x26/0x140 kernel/sched/core.c:537

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #3 (&rq->__lock){-.-.}-{2:2}:
lock_acquire+0x1f8/0x5a0 kernel/locking/lockdep.c:5662
_raw_spin_lock_nested+0x2d/0x40 kernel/locking/spinlock.c:378
raw_spin_rq_lock_nested+0x26/0x140 kernel/sched/core.c:537
raw_spin_rq_lock kernel/sched/sched.h:1354 [inline]
rq_lock kernel/sched/sched.h:1644 [inline]
task_fork_fair+0x5d/0x350 kernel/sched/fair.c:11869
sched_cgroup_fork+0x374/0x400 kernel/sched/core.c:4686
copy_process+0x2442/0x4060 kernel/fork.c:2384
kernel_clone+0x222/0x920 kernel/fork.c:2682
user_mode_thread+0x12e/0x190 kernel/fork.c:2758
rest_init+0x23/0x300 init/main.c:697
start_kernel+0x0/0x53f init/main.c:892
start_kernel+0x496/0x53f init/main.c:1139
secondary_startup_64_no_verify+0xcf/0xdb

-> #2 (&p->pi_lock){-.-.}-{2:2}:
lock_acquire+0x1f8/0x5a0 kernel/locking/lockdep.c:5662
__raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
_raw_spin_lock_irqsave+0xd1/0x120 kernel/locking/spinlock.c:162
try_to_wake_up+0xad/0x12e0 kernel/sched/core.c:4112
signal_wake_up_state kernel/signal.c:780 [inline]
signal_wake_up include/linux/sched/signal.h:457 [inline]
complete_signal+0x796/0xbd0 kernel/signal.c:1074
__send_signal_locked+0xb1a/0xdc0 kernel/signal.c:1194
do_notify_parent+0xe2b/0x1100 kernel/signal.c:2120
exit_notify kernel/exit.c:744 [inline]
do_exit+0x172e/0x26a0 kernel/exit.c:889
do_group_exit+0x202/0x2b0 kernel/exit.c:1019
__do_sys_exit_group kernel/exit.c:1030 [inline]
__se_sys_exit_group kernel/exit.c:1028 [inline]
__x64_sys_exit_group+0x3b/0x40 kernel/exit.c:1028
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81
entry_SYSCALL_64_after_hwframe+0x68/0xd2

-> #1 (&sighand->siglock){....}-{2:2}:
lock_acquire+0x1f8/0x5a0 kernel/locking/lockdep.c:5662
__raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
_raw_spin_lock_irqsave+0xd1/0x120 kernel/locking/spinlock.c:162
__lock_task_sighand+0x145/0x2d0 kernel/signal.c:1410
lock_task_sighand include/linux/sched/signal.h:745 [inline]
do_send_sig_info kernel/signal.c:1299 [inline]
group_send_sig_info+0x26c/0x300 kernel/signal.c:1448
bpf_send_signal_common+0x2d8/0x420 kernel/trace/bpf_trace.c:882
____bpf_send_signal_thread kernel/trace/bpf_trace.c:899 [inline]
bpf_send_signal_thread+0x12/0x20 kernel/trace/bpf_trace.c:897
0xffffffffa0000965
bpf_dispatcher_nop_func include/linux/bpf.h:989 [inline]
__bpf_prog_run include/linux/filter.h:603 [inline]
bpf_prog_run include/linux/filter.h:610 [inline]
__bpf_trace_run kernel/trace/bpf_trace.c:2273 [inline]
bpf_trace_run4+0x253/0x470 kernel/trace/bpf_trace.c:2314
trace_mmap_lock_acquire_returned include/trace/events/mmap_lock.h:52 [inline]
__mmap_lock_do_trace_acquire_returned+0x5e3/0x670 mm/mmap_lock.c:237
__mmap_lock_trace_acquire_returned include/linux/mmap_lock.h:36 [inline]
mmap_read_trylock include/linux/mmap_lock.h:137 [inline]
get_mmap_lock_carefully mm/memory.c:5304 [inline]
lock_mm_and_find_vma+0x219/0x2e0 mm/memory.c:5366
do_user_addr_fault arch/x86/mm/fault.c:1343 [inline]
handle_page_fault arch/x86/mm/fault.c:1462 [inline]
exc_page_fault+0x169/0x660 arch/x86/mm/fault.c:1518
asm_exc_page_fault+0x22/0x30 arch/x86/include/asm/idtentry.h:570
strncpy_from_user+0x159/0x360 lib/strncpy_from_user.c:139
strncpy_from_bpfptr include/linux/bpfptr.h:85 [inline]
bpf_prog_load+0x188/0x1bb0 kernel/bpf/syscall.c:2515
__sys_bpf+0x382/0x6c0 kernel/bpf/syscall.c:5005
__do_sys_bpf kernel/bpf/syscall.c:5109 [inline]
__se_sys_bpf kernel/bpf/syscall.c:5107 [inline]
__x64_sys_bpf+0x78/0x90 kernel/bpf/syscall.c:5107
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81
entry_SYSCALL_64_after_hwframe+0x68/0xd2

-> #0 (lock#9){+.+.}-{2:2}:
check_prev_add kernel/locking/lockdep.c:3090 [inline]
check_prevs_add kernel/locking/lockdep.c:3209 [inline]
validate_chain+0x1661/0x5950 kernel/locking/lockdep.c:3825
__lock_acquire+0x125b/0x1f80 kernel/locking/lockdep.c:5049
lock_acquire+0x1f8/0x5a0 kernel/locking/lockdep.c:5662
local_lock_acquire include/linux/local_lock_internal.h:29 [inline]
__mmap_lock_do_trace_acquire_returned+0x9d/0x670 mm/mmap_lock.c:237
__mmap_lock_trace_acquire_returned include/linux/mmap_lock.h:36 [inline]
mmap_read_trylock include/linux/mmap_lock.h:137 [inline]
stack_map_get_build_id_offset+0x99e/0x9c0 kernel/bpf/stackmap.c:144
__bpf_get_stack+0x495/0x570 kernel/bpf/stackmap.c:452
____bpf_get_stack_raw_tp kernel/trace/bpf_trace.c:1877 [inline]
bpf_get_stack_raw_tp+0x1b2/0x220 kernel/trace/bpf_trace.c:1867
bpf_prog_e6cf5f9c69743609+0x3a/0x3e
bpf_dispatcher_nop_func include/linux/bpf.h:989 [inline]
__bpf_prog_run include/linux/filter.h:603 [inline]
bpf_prog_run include/linux/filter.h:610 [inline]
__bpf_trace_run kernel/trace/bpf_trace.c:2273 [inline]
bpf_trace_run4+0x253/0x470 kernel/trace/bpf_trace.c:2314
trace_sched_switch include/trace/events/sched.h:222 [inline]
__schedule+0x2116/0x4550 kernel/sched/core.c:6555
preempt_schedule_irq+0xf7/0x1c0 kernel/sched/core.c:6870
irqentry_exit+0x53/0x80 kernel/entry/common.c:439
asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:653
check_kcov_mode kernel/kcov.c:173 [inline]
__sanitizer_cov_trace_pc+0x2c/0x60 kernel/kcov.c:207
wp_page_copy+0x278/0x18c0 mm/memory.c:3131
handle_pte_fault mm/memory.c:5031 [inline]
__handle_mm_fault mm/memory.c:5155 [inline]
handle_mm_fault+0x2525/0x5340 mm/memory.c:5276
do_user_addr_fault arch/x86/mm/fault.c:1371 [inline]
handle_page_fault arch/x86/mm/fault.c:1462 [inline]
exc_page_fault+0x26f/0x660 arch/x86/mm/fault.c:1518
asm_exc_page_fault+0x22/0x30 arch/x86/include/asm/idtentry.h:570

other info that might help us debug this:

Chain exists of:
lock#9 --> &p->pi_lock --> &rq->__lock

Possible unsafe locking scenario:

CPU0 CPU1
---- ----
lock(&rq->__lock);
lock(&p->pi_lock);
lock(&rq->__lock);
lock(lock#9);

*** DEADLOCK ***

4 locks held by syz-executor271/3685:
#0: ffff88802343bd58 (&mm->mmap_lock){++++}-{3:3}, at: mmap_read_trylock include/linux/mmap_lock.h:136 [inline]
#0: ffff88802343bd58 (&mm->mmap_lock){++++}-{3:3}, at: get_mmap_lock_carefully mm/memory.c:5304 [inline]
#0: ffff88802343bd58 (&mm->mmap_lock){++++}-{3:3}, at: lock_mm_and_find_vma+0x2e/0x2e0 mm/memory.c:5366
#1: ffff8880b983aa18 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x26/0x140 kernel/sched/core.c:537
#2: ffffffff8d12ac40 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:350 [inline]
#2: ffffffff8d12ac40 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:791 [inline]
#2: ffffffff8d12ac40 (rcu_read_lock){....}-{1:2}, at: __bpf_trace_run kernel/trace/bpf_trace.c:2272 [inline]
#2: ffffffff8d12ac40 (rcu_read_lock){....}-{1:2}, at: bpf_trace_run4+0x16a/0x470 kernel/trace/bpf_trace.c:2314
#3: ffff88802343bd58 (&mm->mmap_lock){++++}-{3:3}, at: mmap_read_trylock include/linux/mmap_lock.h:136 [inline]
#3: ffff88802343bd58 (&mm->mmap_lock){++++}-{3:3}, at: stack_map_get_build_id_offset+0x232/0x9c0 kernel/bpf/stackmap.c:144

stack backtrace:
CPU: 0 PID: 3685 Comm: syz-executor271 Not tainted 6.1.86-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0x1e3/0x2cb lib/dump_stack.c:106
check_noncircular+0x2fa/0x3b0 kernel/locking/lockdep.c:2170
check_prev_add kernel/locking/lockdep.c:3090 [inline]
check_prevs_add kernel/locking/lockdep.c:3209 [inline]
validate_chain+0x1661/0x5950 kernel/locking/lockdep.c:3825
__lock_acquire+0x125b/0x1f80 kernel/locking/lockdep.c:5049
lock_acquire+0x1f8/0x5a0 kernel/locking/lockdep.c:5662
local_lock_acquire include/linux/local_lock_internal.h:29 [inline]
__mmap_lock_do_trace_acquire_returned+0x9d/0x670 mm/mmap_lock.c:237
__mmap_lock_trace_acquire_returned include/linux/mmap_lock.h:36 [inline]
mmap_read_trylock include/linux/mmap_lock.h:137 [inline]
stack_map_get_build_id_offset+0x99e/0x9c0 kernel/bpf/stackmap.c:144
__bpf_get_stack+0x495/0x570 kernel/bpf/stackmap.c:452
____bpf_get_stack_raw_tp kernel/trace/bpf_trace.c:1877 [inline]
bpf_get_stack_raw_tp+0x1b2/0x220 kernel/trace/bpf_trace.c:1867
bpf_prog_e6cf5f9c69743609+0x3a/0x3e
bpf_dispatcher_nop_func include/linux/bpf.h:989 [inline]
__bpf_prog_run include/linux/filter.h:603 [inline]
bpf_prog_run include/linux/filter.h:610 [inline]
__bpf_trace_run kernel/trace/bpf_trace.c:2273 [inline]
bpf_trace_run4+0x253/0x470 kernel/trace/bpf_trace.c:2314
trace_sched_switch include/trace/events/sched.h:222 [inline]
__schedule+0x2116/0x4550 kernel/sched/core.c:6555
preempt_schedule_irq+0xf7/0x1c0 kernel/sched/core.c:6870
irqentry_exit+0x53/0x80 kernel/entry/common.c:439
asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:653
RIP: 0010:check_kcov_mode kernel/kcov.c:175 [inline]
RIP: 0010:__sanitizer_cov_trace_pc+0x2c/0x60 kernel/kcov.c:207
Code: 04 24 65 48 8b 0d e4 df 77 7e 65 8b 15 e5 df 77 7e f7 c2 00 01 ff 00 74 11 f7 c2 00 01 00 00 74 35 83 b9 1c 16 00 00 00 74 2c <8b> 91 f8 15 00 00 83 fa 02 75 21 48 8b 91 00 16 00 00 48 8b 32 48
RSP: 0000:ffffc90004b3fa78 EFLAGS: 00000246
RAX: ffffffff81ce1368 RBX: ffffc90004b3fe28 RCX: ffff88807b0d8000
RDX: 0000000080000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc90004b3fc30 R08: ffffffff81dee611 R09: fffffbfff1ce6ede
R10: 0000000000000000 R11: dffffc0000000001 R12: ffff888018fea958
R13: ffffc90004b3fe10 R14: 000000000000fd84 R15: 000000000000fd84
wp_page_copy+0x278/0x18c0 mm/memory.c:3131
handle_pte_fault mm/memory.c:5031 [inline]
__handle_mm_fault mm/memory.c:5155 [inline]
handle_mm_fault+0x2525/0x5340 mm/memory.c:5276
do_user_addr_fault arch/x86/mm/fault.c:1371 [inline]
handle_page_fault arch/x86/mm/fault.c:1462 [inline]
exc_page_fault+0x26f/0x660 arch/x86/mm/fault.c:1518
asm_exc_page_fault+0x22/0x30 arch/x86/include/asm/idtentry.h:570
RIP: 0033:0x7f8054112bd0
Code: 84 dd fe ff ff 4c 89 e7 e8 ed 90 00 00 e9 d0 fe ff ff 0f 1f 84 00 00 00 00 00 49 8b 06 48 89 45 00 48 85 c0 0f 85 85 00 00 00 <c6> 05 39 35 0a 00 01 31 c0 87 05 09 31 0a 00 83 f8 01 0f 8f 84 00
RSP: 002b:00007ffc78876da0 EFLAGS: 00010246
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000004
RDX: 0000000000000001 RSI: 0000000000000000 RDI: 00007f80541b4ad8
RBP: 00007f80541b3120 R08: 00007ffc78876e0c R09: 00007ffc78876e0c
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f80541b5ce8
R13: 0000000000000000 R14: 00007f80541b5d00 R15: 00007f805410b6e0
</TASK>
----------------
Code disassembly (best guess):
0: 04 24 add $0x24,%al
2: 65 48 8b 0d e4 df 77 mov %gs:0x7e77dfe4(%rip),%rcx # 0x7e77dfee
9: 7e
a: 65 8b 15 e5 df 77 7e mov %gs:0x7e77dfe5(%rip),%edx # 0x7e77dff6
11: f7 c2 00 01 ff 00 test $0xff0100,%edx
17: 74 11 je 0x2a
19: f7 c2 00 01 00 00 test $0x100,%edx
1f: 74 35 je 0x56
21: 83 b9 1c 16 00 00 00 cmpl $0x0,0x161c(%rcx)
28: 74 2c je 0x56
* 2a: 8b 91 f8 15 00 00 mov 0x15f8(%rcx),%edx <-- trapping instruction
30: 83 fa 02 cmp $0x2,%edx
33: 75 21 jne 0x56
35: 48 8b 91 00 16 00 00 mov 0x1600(%rcx),%rdx
3c: 48 8b 32 mov (%rdx),%rsi
3f: 48 rex.W


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