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rcuref - imbalanced put()
WARNING: lib/rcuref.c:266 at rcuref_put_slowpath+0x16e/0x1d0 lib/rcuref.c:266, CPU#0: ktimers/0/16
Modules linked in:
CPU: 0 UID: 0 PID: 16 Comm: ktimers/0 Not tainted syzkaller #0 PREEMPT_{RT,(full)}
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
RIP: 0010:rcuref_put_slowpath+0x16e/0x1d0 lib/rcuref.c:266
Code: c1 e8 03 42 0f b6 04 38 84 c0 75 48 c7 03 00 00 00 a0 31 c0 e9 6d ff ff ff e8 fe 13 80 06 e8 49 d7 14 fd 48 8d 3d 62 f3 e6 0a <67> 48 0f b9 3a 48 89 df be 04 00 00 00 e8 40 b3 80 fd 48 89 d8 48
RSP: 0018:ffffc90000157560 EFLAGS: 00010246
RAX: ffffffff84b04017 RBX: ffff888025328740 RCX: ffff88801d680000
RDX: 0000000000000100 RSI: 0000000000000000 RDI: ffffffff8f973380
RBP: ffffc900001575e8 R08: 0000000000000000 R09: 0000000000000100
R10: dffffc0000000000 R11: ffffed1004a650e9 R12: 1ffff9200002aeac
R13: dffffc0000000000 R14: 00000000dfffffff R15: dffffc0000000000
FS: 0000000000000000(0000) GS:ffff888125ed3000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f67d5f2c558 CR3: 0000000026bb4000 CR4: 00000000003526f0
Call Trace:
<TASK>
__rcuref_put include/linux/rcuref.h:117 [inline]
rcuref_put+0x15b/0x170 include/linux/rcuref.h:173
dst_release+0x31/0x1b0 net/core/dst.c:251
dst_cache_per_cpu_get+0x25a/0x2d0 net/core/dst_cache.c:57
dst_cache_get+0x10d/0x1e0 net/core/dst_cache.c:75
tipc_udp_xmit+0xcf/0xb30 net/tipc/udp_media.c:177
tipc_bearer_xmit_skb+0x2b3/0x400 net/tipc/bearer.c:576
tipc_disc_timeout+0x642/0x790 net/tipc/discover.c:338
call_timer_fn+0x192/0x5e0 kernel/time/timer.c:1748
expire_timers kernel/time/timer.c:1799 [inline]
__run_timers kernel/time/timer.c:2374 [inline]
__run_timer_base+0x67b/0x9b0 kernel/time/timer.c:2386
run_timer_base kernel/time/timer.c:2395 [inline]
run_timer_softirq+0xb7/0x170 kernel/time/timer.c:2405
handle_softirqs+0x1d9/0x6c0 kernel/softirq.c:626
__do_softirq kernel/softirq.c:660 [inline]
run_ktimerd+0x69/0x100 kernel/softirq.c:1155
smpboot_thread_fn+0x57c/0xa80 kernel/smpboot.c:160
kthread+0x388/0x470 kernel/kthread.c:436
ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
</TASK>
----------------
Code disassembly (best guess):
0: c1 e8 03 shr $0x3,%eax
3: 42 0f b6 04 38 movzbl (%rax,%r15,1),%eax
8: 84 c0 test %al,%al
a: 75 48 jne 0x54
c: c7 03 00 00 00 a0 movl $0xa0000000,(%rbx)
12: 31 c0 xor %eax,%eax
14: e9 6d ff ff ff jmp 0xffffff86
19: e8 fe 13 80 06 call 0x680141c
1e: e8 49 d7 14 fd call 0xfd14d76c
23: 48 8d 3d 62 f3 e6 0a lea 0xae6f362(%rip),%rdi # 0xae6f38c
* 2a: 67 48 0f b9 3a ud1 (%edx),%rdi <-- trapping instruction
2f: 48 89 df mov %rbx,%rdi
32: be 04 00 00 00 mov $0x4,%esi
37: e8 40 b3 80 fd call 0xfd80b37c
3c: 48 89 d8 mov %rbx,%rax
3f: 48 rex.W