syzbot


possible deadlock in queue_stack_map_push_elem

Status: upstream: reported C repro on 2024/04/17 21:25
Subsystems: bpf
[Documentation on labels]
Reported-by: syzbot+252bc5c744d0bba917e1@syzkaller.appspotmail.com
First crash: 16d, last: 2d18h
Discussions (1)
Title Replies (including bot) Last reply
[syzbot] [bpf?] possible deadlock in queue_stack_map_push_elem 0 (1) 2024/04/17 21:25
Similar bugs (1)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-6.1 possible deadlock in queue_stack_map_push_elem origin:upstream C 2 3d20h 18d 0/3 upstream: reported C repro on 2024/04/11 18:39

Sample crash report:
============================================
WARNING: possible recursive locking detected
6.9.0-rc5-syzkaller-00171-gb2ff42c6d3ab #0 Not tainted
--------------------------------------------
syz-executor231/5237 is trying to acquire lock:
ffff8880792df1d8 (&qs->lock){-.-.}-{2:2}, at: queue_stack_map_push_elem+0x1b2/0x660 kernel/bpf/queue_stack_maps.c:210

but task is already holding lock:
ffff8880792de1d8 (&qs->lock){-.-.}-{2:2}, at: queue_stack_map_push_elem+0x1b2/0x660 kernel/bpf/queue_stack_maps.c:210

other info that might help us debug this:
 Possible unsafe locking scenario:

       CPU0
       ----
  lock(&qs->lock);
  lock(&qs->lock);

 *** DEADLOCK ***

 May be due to missing lock nesting notation

4 locks held by syz-executor231/5237:
 #0: ffffffff8e4099e8 (pcpu_alloc_mutex){+.+.}-{3:3}, at: pcpu_alloc+0x27b/0x16f0 mm/percpu.c:1769
 #1: ffffffff8e334d20 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:329 [inline]
 #1: ffffffff8e334d20 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:781 [inline]
 #1: ffffffff8e334d20 (rcu_read_lock){....}-{1:2}, at: __bpf_trace_run kernel/trace/bpf_trace.c:2380 [inline]
 #1: ffffffff8e334d20 (rcu_read_lock){....}-{1:2}, at: bpf_trace_run2+0x114/0x420 kernel/trace/bpf_trace.c:2420
 #2: ffff8880792de1d8 (&qs->lock){-.-.}-{2:2}, at: queue_stack_map_push_elem+0x1b2/0x660 kernel/bpf/queue_stack_maps.c:210
 #3: ffffffff8e334d20 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:329 [inline]
 #3: ffffffff8e334d20 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:781 [inline]
 #3: ffffffff8e334d20 (rcu_read_lock){....}-{1:2}, at: __bpf_trace_run kernel/trace/bpf_trace.c:2380 [inline]
 #3: ffffffff8e334d20 (rcu_read_lock){....}-{1:2}, at: bpf_trace_run2+0x114/0x420 kernel/trace/bpf_trace.c:2420

stack backtrace:
CPU: 1 PID: 5237 Comm: syz-executor231 Not tainted 6.9.0-rc5-syzkaller-00171-gb2ff42c6d3ab #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+0x241/0x360 lib/dump_stack.c:114
 check_deadlock kernel/locking/lockdep.c:3062 [inline]
 validate_chain+0x15c1/0x58e0 kernel/locking/lockdep.c:3856
 __lock_acquire+0x1346/0x1fd0 kernel/locking/lockdep.c:5137
 lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5754
 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
 _raw_spin_lock_irqsave+0xd5/0x120 kernel/locking/spinlock.c:162
 queue_stack_map_push_elem+0x1b2/0x660 kernel/bpf/queue_stack_maps.c:210
 bpf_prog_80daba7f9ca62790+0x42/0x46
 bpf_dispatcher_nop_func include/linux/bpf.h:1234 [inline]
 __bpf_prog_run include/linux/filter.h:657 [inline]
 bpf_prog_run include/linux/filter.h:664 [inline]
 __bpf_trace_run kernel/trace/bpf_trace.c:2381 [inline]
 bpf_trace_run2+0x204/0x420 kernel/trace/bpf_trace.c:2420
 __traceiter_contention_end+0x7b/0xb0 include/trace/events/lock.h:122
 trace_contention_end+0x114/0x140 include/trace/events/lock.h:122
 __pv_queued_spin_lock_slowpath+0x939/0xc60 kernel/locking/qspinlock.c:560
 pv_queued_spin_lock_slowpath arch/x86/include/asm/paravirt.h:584 [inline]
 queued_spin_lock_slowpath+0x42/0x50 arch/x86/include/asm/qspinlock.h:51
 queued_spin_lock include/asm-generic/qspinlock.h:114 [inline]
 do_raw_spin_lock+0x272/0x370 kernel/locking/spinlock_debug.c:116
 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:111 [inline]
 _raw_spin_lock_irqsave+0xe1/0x120 kernel/locking/spinlock.c:162
 queue_stack_map_push_elem+0x1b2/0x660 kernel/bpf/queue_stack_maps.c:210
 bpf_prog_80daba7f9ca62790+0x42/0x46
 bpf_dispatcher_nop_func include/linux/bpf.h:1234 [inline]
 __bpf_prog_run include/linux/filter.h:657 [inline]
 bpf_prog_run include/linux/filter.h:664 [inline]
 __bpf_trace_run kernel/trace/bpf_trace.c:2381 [inline]
 bpf_trace_run2+0x204/0x420 kernel/trace/bpf_trace.c:2420
 __traceiter_contention_end+0x7b/0xb0 include/trace/events/lock.h:122
 trace_contention_end+0xf5/0x120 include/trace/events/lock.h:122
 __mutex_lock_common kernel/locking/mutex.c:617 [inline]
 __mutex_lock+0x2e5/0xd70 kernel/locking/mutex.c:752
 pcpu_alloc+0x27b/0x16f0 mm/percpu.c:1769
 bpf_prog_alloc_no_stats+0x10b/0x4a0 kernel/bpf/core.c:112
 bpf_prog_alloc+0x3b/0x1b0 kernel/bpf/core.c:144
 bpf_prog_load+0x7f7/0x20f0 kernel/bpf/syscall.c:2805
 __sys_bpf+0x4ee/0x810 kernel/bpf/syscall.c:5660
 __do_sys_bpf kernel/bpf/syscall.c:5767 [inline]
 __se_sys_bpf kernel/bpf/syscall.c:5765 [inline]
 __x64_sys_bpf+0x7c/0x90 kernel/bpf/syscall.c:5765
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xf5/0x240 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fbb9af16e29
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 c1 17 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 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffeb251a908 EFLAGS: 00000246 ORIG_RAX: 0000000000000141
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007fbb9af16e29
RDX: 0000000000000090 RSI: 0000000020000a40 RDI: 0000000000000005
RBP: 0000000000000000 R08: 0000000000000000 R09: 00000000000000a0
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
 </TASK>

Crashes (4):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/04/27 17:33 bpf b2ff42c6d3ab 07b455f9 .config strace log report syz C [disk image] [vmlinux] [kernel image] ci-upstream-bpf-kasan-gce possible deadlock in queue_stack_map_push_elem
2024/04/14 09:19 net f99c5f563c17 c8349e48 .config strace log report syz C [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce possible deadlock in queue_stack_map_push_elem
2024/04/13 21:22 bpf 443574b03387 c8349e48 .config strace log report syz C [disk image] [vmlinux] [kernel image] ci-upstream-bpf-kasan-gce possible deadlock in queue_stack_map_push_elem
2024/04/14 10:39 bpf 443574b03387 c8349e48 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-bpf-kasan-gce possible deadlock in queue_stack_map_push_elem
* Struck through repros no longer work on HEAD.