======================================================
WARNING: possible circular locking dependency detected
5.15.162-syzkaller #0 Not tainted
------------------------------------------------------
syz-executor/10812 is trying to acquire lock:
ffff8880683f0018 (&sighand->siglock){-.-.}-{2:2}, at: __lock_task_sighand+0x11a/0x290 kernel/signal.c:1404
but task is already holding lock:
ffff8880b9b35bb8 (lock#10){+.+.}-{2:2}, at: local_lock_acquire+0xd/0x170 include/linux/local_lock_internal.h:28
which lock already depends on the new lock.
the existing dependency chain (in reverse order) is:
-> #3 (lock#10){+.+.}-{2:2}:
lock_acquire+0x1db/0x4f0 kernel/locking/lockdep.c:5623
local_lock_acquire+0x29/0x170 include/linux/local_lock_internal.h:29
__mmap_lock_do_trace_acquire_returned+0x7c/0x340 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+0x612/0x930 kernel/bpf/stackmap.c:185
__bpf_get_stack+0x495/0x570 kernel/bpf/stackmap.c:496
____bpf_get_stack_raw_tp kernel/trace/bpf_trace.c:1490 [inline]
bpf_get_stack_raw_tp+0x1b2/0x220 kernel/trace/bpf_trace.c:1480
0xffffffffa002a47e
bpf_dispatcher_nop_func include/linux/bpf.h:790 [inline]
__bpf_prog_run include/linux/filter.h:628 [inline]
bpf_prog_run include/linux/filter.h:635 [inline]
__bpf_trace_run kernel/trace/bpf_trace.c:1880 [inline]
bpf_trace_run2+0x19e/0x340 kernel/trace/bpf_trace.c:1917
trace_tlb_flush+0xed/0x110 include/trace/events/tlb.h:38
switch_mm_irqs_off+0x748/0xa30
context_switch kernel/sched/core.c:5016 [inline]
__schedule+0x1167/0x45b0 kernel/sched/core.c:6376
schedule+0x11b/0x1f0 kernel/sched/core.c:6459
freezable_schedule include/linux/freezer.h:172 [inline]
do_nanosleep+0x1bc/0x7b0 kernel/time/hrtimer.c:2045
hrtimer_nanosleep+0x24d/0x490 kernel/time/hrtimer.c:2098
__do_sys_clock_nanosleep kernel/time/posix-timers.c:1313 [inline]
__se_sys_clock_nanosleep+0x323/0x3b0 kernel/time/posix-timers.c:1290
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x66/0xd0
-> #2 (&rq->__lock){-.-.}-{2:2}:
lock_acquire+0x1db/0x4f0 kernel/locking/lockdep.c:5623
_raw_spin_lock_nested+0x2d/0x40 kernel/locking/spinlock.c:368
raw_spin_rq_lock_nested+0x26/0x140 kernel/sched/core.c:475
raw_spin_rq_lock kernel/sched/sched.h:1326 [inline]
rq_lock kernel/sched/sched.h:1621 [inline]
task_fork_fair+0x5d/0x350 kernel/sched/fair.c:11495
sched_cgroup_fork+0x2d3/0x330 kernel/sched/core.c:4466
copy_process+0x224a/0x3ef0 kernel/fork.c:2320
kernel_clone+0x210/0x960 kernel/fork.c:2604
kernel_thread+0x168/0x1e0 kernel/fork.c:2656
rest_init+0x21/0x330 init/main.c:706
start_kernel+0x48c/0x540 init/main.c:1140
secondary_startup_64_no_verify+0xb1/0xbb
-> #1 (&p->pi_lock){-.-.}-{2:2}:
lock_acquire+0x1db/0x4f0 kernel/locking/lockdep.c:5623
__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+0xae/0x1300 kernel/sched/core.c:4030
signal_wake_up_state kernel/signal.c:770 [inline]
signal_wake_up include/linux/sched/signal.h:421 [inline]
complete_signal+0x5a0/0x9a0 kernel/signal.c:1062
__send_signal+0xaaf/0xd40 kernel/signal.c:1182
do_notify_parent+0xc1e/0xf00 kernel/signal.c:2113
exit_notify kernel/exit.c:729 [inline]
do_exit+0x1464/0x2480 kernel/exit.c:892
do_group_exit+0x144/0x310 kernel/exit.c:994
__do_sys_exit_group kernel/exit.c:1005 [inline]
__se_sys_exit_group kernel/exit.c:1003 [inline]
__x64_sys_exit_group+0x3b/0x40 kernel/exit.c:1003
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x66/0xd0
-> #0 (&sighand->siglock){-.-.}-{2:2}:
check_prev_add kernel/locking/lockdep.c:3053 [inline]
check_prevs_add kernel/locking/lockdep.c:3172 [inline]
validate_chain+0x1649/0x5930 kernel/locking/lockdep.c:3788
__lock_acquire+0x1295/0x1ff0 kernel/locking/lockdep.c:5012
lock_acquire+0x1db/0x4f0 kernel/locking/lockdep.c:5623
__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+0x11a/0x290 kernel/signal.c:1404
lock_task_sighand include/linux/sched/signal.h:704 [inline]
do_send_sig_info kernel/signal.c:1293 [inline]
group_send_sig_info+0x23f/0x2d0 kernel/signal.c:1442
bpf_send_signal_common+0x2d8/0x420 kernel/trace/bpf_trace.c:824
____bpf_send_signal kernel/trace/bpf_trace.c:829 [inline]
bpf_send_signal+0x15/0x20 kernel/trace/bpf_trace.c:827
bpf_prog_9fbc3d1d47c9b36c+0x1a/0x700
bpf_dispatcher_nop_func include/linux/bpf.h:790 [inline]
__bpf_prog_run include/linux/filter.h:628 [inline]
bpf_prog_run include/linux/filter.h:635 [inline]
__bpf_trace_run kernel/trace/bpf_trace.c:1880 [inline]
bpf_trace_run4+0x1ea/0x390 kernel/trace/bpf_trace.c:1919
trace_mmap_lock_acquire_returned include/trace/events/mmap_lock.h:44 [inline]
__mmap_lock_do_trace_acquire_returned+0x2d6/0x340 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]
do_user_addr_fault arch/x86/mm/fault.c:1298 [inline]
handle_page_fault arch/x86/mm/fault.c:1445 [inline]
exc_page_fault+0x564/0x700 arch/x86/mm/fault.c:1501
asm_exc_page_fault+0x22/0x30 arch/x86/include/asm/idtentry.h:568
__put_user_nocheck_4+0x3/0x11
schedule_tail+0x92/0xb0 kernel/sched/core.c:4970
ret_from_fork+0x8/0x30 arch/x86/entry/entry_64.S:285
other info that might help us debug this:
Chain exists of:
&sighand->siglock --> &rq->__lock --> lock#10
Possible unsafe locking scenario:
CPU0 CPU1
---- ----
lock(lock#10);
lock(&rq->__lock);
lock(lock#10);
lock(&sighand->siglock);
*** DEADLOCK ***
5 locks held by syz-executor/10812:
#0: ffff88807e840f28 (&mm->mmap_lock){++++}-{3:3}, at: mmap_read_trylock include/linux/mmap_lock.h:136 [inline]
#0: ffff88807e840f28 (&mm->mmap_lock){++++}-{3:3}, at: do_user_addr_fault arch/x86/mm/fault.c:1298 [inline]
#0: ffff88807e840f28 (&mm->mmap_lock){++++}-{3:3}, at: handle_page_fault arch/x86/mm/fault.c:1445 [inline]
#0: ffff88807e840f28 (&mm->mmap_lock){++++}-{3:3}, at: exc_page_fault+0x181/0x700 arch/x86/mm/fault.c:1501
#1: ffff8880b9b35bb8 (lock#10){+.+.}-{2:2}, at: local_lock_acquire+0xd/0x170 include/linux/local_lock_internal.h:28
#2: ffffffff8c91fb20 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x5/0x30 include/linux/rcupdate.h:311
#3: ffffffff8c91fb20 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x5/0x30 include/linux/rcupdate.h:311
#4: ffffffff8c91fb20 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x5/0x30 include/linux/rcupdate.h:311
stack backtrace:
CPU: 1 PID: 10812 Comm: syz-executor Not tainted 5.15.162-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/07/2024
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0x1e3/0x2d0 lib/dump_stack.c:106
check_noncircular+0x2f8/0x3b0 kernel/locking/lockdep.c:2133
check_prev_add kernel/locking/lockdep.c:3053 [inline]
check_prevs_add kernel/locking/lockdep.c:3172 [inline]
validate_chain+0x1649/0x5930 kernel/locking/lockdep.c:3788
__lock_acquire+0x1295/0x1ff0 kernel/locking/lockdep.c:5012
lock_acquire+0x1db/0x4f0 kernel/locking/lockdep.c:5623
__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+0x11a/0x290 kernel/signal.c:1404
lock_task_sighand include/linux/sched/signal.h:704 [inline]
do_send_sig_info kernel/signal.c:1293 [inline]
group_send_sig_info+0x23f/0x2d0 kernel/signal.c:1442
bpf_send_signal_common+0x2d8/0x420 kernel/trace/bpf_trace.c:824
____bpf_send_signal kernel/trace/bpf_trace.c:829 [inline]
bpf_send_signal+0x15/0x20 kernel/trace/bpf_trace.c:827
bpf_prog_9fbc3d1d47c9b36c+0x1a/0x700
bpf_dispatcher_nop_func include/linux/bpf.h:790 [inline]
__bpf_prog_run include/linux/filter.h:628 [inline]
bpf_prog_run include/linux/filter.h:635 [inline]
__bpf_trace_run kernel/trace/bpf_trace.c:1880 [inline]
bpf_trace_run4+0x1ea/0x390 kernel/trace/bpf_trace.c:1919
trace_mmap_lock_acquire_returned include/trace/events/mmap_lock.h:44 [inline]
__mmap_lock_do_trace_acquire_returned+0x2d6/0x340 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]
do_user_addr_fault arch/x86/mm/fault.c:1298 [inline]
handle_page_fault arch/x86/mm/fault.c:1445 [inline]
exc_page_fault+0x564/0x700 arch/x86/mm/fault.c:1501
asm_exc_page_fault+0x22/0x30 arch/x86/include/asm/idtentry.h:568
RIP: 0010:__put_user_nocheck_4+0x3/0x11
Code: 00 00 48 39 d9 73 54 0f 01 cb 66 89 01 31 c9 0f 01 ca c3 0f 1f 44 00 00 48 bb fd ef ff ff ff 7f 00 00 48 39 d9 73 34 0f 01 cb <89> 01 31 c9 0f 01 ca c3 66 0f 1f 44 00 00 48 bb f9 ef ff ff ff 7f
RSP: 0018:ffffc900030d7f28 EFLAGS: 00050293
RAX: 00000000000004e1 RBX: 00007fffffffeffd RCX: 00005555563e47d0
RDX: 0000000000000000 RSI: ffffffff8a8b3ca0 RDI: ffffffff8ad8f680
RBP: 0000000000000000 R08: dffffc0000000000 R09: fffffbfff1bc8e76
R10: 0000000000000000 R11: dffffc0000000001 R12: ffff8880570d4220
R13: 0000000000000000 R14: ffff8880570d3b80 R15: dffffc0000000000
schedule_tail+0x92/0xb0 kernel/sched/core.c:4970
ret_from_fork+0x8/0x30 arch/x86/entry/entry_64.S:285
</TASK>
----------------
Code disassembly (best guess):
0: 00 00 add %al,(%rax)
2: 48 39 d9 cmp %rbx,%rcx
5: 73 54 jae 0x5b
7: 0f 01 cb stac
a: 66 89 01 mov %ax,(%rcx)
d: 31 c9 xor %ecx,%ecx
f: 0f 01 ca clac
12: c3 ret
13: 0f 1f 44 00 00 nopl 0x0(%rax,%rax,1)
18: 48 bb fd ef ff ff ff movabs $0x7fffffffeffd,%rbx
1f: 7f 00 00
22: 48 39 d9 cmp %rbx,%rcx
25: 73 34 jae 0x5b
27: 0f 01 cb stac
* 2a: 89 01 mov %eax,(%rcx) <-- trapping instruction
2c: 31 c9 xor %ecx,%ecx
2e: 0f 01 ca clac
31: c3 ret
32: 66 0f 1f 44 00 00 nopw 0x0(%rax,%rax,1)
38: 48 rex.W
39: bb f9 ef ff ff mov $0xffffeff9,%ebx
3e: ff (bad)
3f: 7f .byte 0x7f