------------[ cut here ]------------
VFS: brelse: Trying to free free buffer
WARNING: CPU: 0 PID: 2596 at fs/buffer.c:1148 __brelse fs/buffer.c:1148 [inline]
WARNING: CPU: 0 PID: 2596 at fs/buffer.c:1148 brelse include/linux/buffer_head.h:325 [inline]
WARNING: CPU: 0 PID: 2596 at fs/buffer.c:1148 __invalidate_bh_lrus fs/buffer.c:1394 [inline]
WARNING: CPU: 0 PID: 2596 at fs/buffer.c:1148 invalidate_bh_lru+0xf8/0x1a0 fs/buffer.c:1407
Modules linked in:
CPU: 0 PID: 2596 Comm: kworker/u4:4 Not tainted 5.15.162-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/07/2024
Workqueue: netns cleanup_net
RIP: 0010:__brelse fs/buffer.c:1148 [inline]
RIP: 0010:brelse include/linux/buffer_head.h:325 [inline]
RIP: 0010:__invalidate_bh_lrus fs/buffer.c:1394 [inline]
RIP: 0010:invalidate_bh_lru+0xf8/0x1a0 fs/buffer.c:1407
Code: 00 e8 6c 69 e4 ff f0 ff 0b eb 21 e8 d2 98 9a ff 41 80 3c 2e 00 75 26 eb 2c e8 c4 98 9a ff 48 c7 c7 20 6c 97 8a e8 e8 40 66 ff <0f> 0b 48 bd 00 00 00 00 00 fc ff df 41 80 3c 2e 00 74 08 4c 89 ff
RSP: 0018:ffffc90000007f60 EFLAGS: 00010046
RAX: 1d141b3e81c04600 RBX: ffff888072f1d230 RCX: ffff888023120000
RDX: 0000000080010203 RSI: 0000000080010203 RDI: 0000000000000000
RBP: 0000000000000000 R08: ffffffff816683dc R09: ffffed1017344f24
R10: 0000000000000000 R11: dffffc0000000001 R12: ffff8880b9a36578
R13: 0000000000000020 R14: 1ffff11017346cb3 R15: ffff8880b9a36598
FS:  0000000000000000(0000) GS:ffff8880b9a00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fb0d843a2f8 CR3: 000000000c68e000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 flush_smp_call_function_queue+0x2b5/0x760 kernel/smp.c:628
 __sysvec_call_function_single+0x9a/0x250 arch/x86/kernel/smp.c:248
 sysvec_call_function_single+0x89/0xb0 arch/x86/kernel/smp.c:243
 </IRQ>
 <TASK>
 asm_sysvec_call_function_single+0x16/0x20 arch/x86/include/asm/idtentry.h:646
RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:161 [inline]
RIP: 0010:_raw_spin_unlock_irqrestore+0xd4/0x130 kernel/locking/spinlock.c:194
Code: 9c 8f 44 24 20 42 80 3c 23 00 74 08 4c 89 f7 e8 82 2d a2 f7 f6 44 24 21 02 75 4e 41 f7 c7 00 02 00 00 74 01 fb bf 01 00 00 00 <e8> d7 6c 2f f7 65 8b 05 d8 72 da 75 85 c0 74 3f 48 c7 04 24 0e 36
RSP: 0018:ffffc9000b1bf660 EFLAGS: 00000206
RAX: 1d141b3e81c04600 RBX: 1ffff92001637ed0 RCX: ffffffff81631708
RDX: dffffc0000000000 RSI: ffffffff8a8b2a00 RDI: 0000000000000001
RBP: ffffc9000b1bf6f0 R08: dffffc0000000000 R09: fffffbfff1f7f22a
R10: 0000000000000000 R11: dffffc0000000001 R12: dffffc0000000000
R13: 1ffff92001637ecc R14: ffffc9000b1bf680 R15: 0000000000000246
 debug_object_assert_init+0x2bf/0x420 lib/debugobjects.c:882
 debug_timer_assert_init kernel/time/timer.c:739 [inline]
 debug_assert_init kernel/time/timer.c:784 [inline]
 del_timer+0xaa/0x310 kernel/time/timer.c:1224
 sk_stop_timer+0x18/0x90 net/core/sock.c:3143
 tcp_clear_xmit_timers include/net/tcp.h:630 [inline]
 tcp_v4_destroy_sock+0x174/0x700 net/ipv4/tcp_ipv4.c:2298
 inet_csk_destroy_sock+0x153/0x370 net/ipv4/inet_connection_sock.c:1040
 __tcp_close+0xa6c/0xec0 net/ipv4/tcp.c:2909
 tcp_close+0x24/0x110 net/ipv4/tcp.c:2921
 inet_release+0x174/0x1f0 net/ipv4/af_inet.c:434
 __sock_release net/socket.c:649 [inline]
 sock_release+0x7a/0x140 net/socket.c:677
 rds_tcp_kill_sock net/rds/tcp.c:596 [inline]
 rds_tcp_exit_net+0x12c/0x620 net/rds/tcp.c:619
 ops_exit_list net/core/net_namespace.c:172 [inline]
 cleanup_net+0x6ce/0xb60 net/core/net_namespace.c:599
 process_one_work+0x8a1/0x10c0 kernel/workqueue.c:2310
 worker_thread+0xaca/0x1280 kernel/workqueue.c:2457
 kthread+0x3f6/0x4f0 kernel/kthread.c:334
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:300
 </TASK>
----------------
Code disassembly (best guess):
   0:	9c                   	pushf
   1:	8f 44 24 20          	pop    0x20(%rsp)
   5:	42 80 3c 23 00       	cmpb   $0x0,(%rbx,%r12,1)
   a:	74 08                	je     0x14
   c:	4c 89 f7             	mov    %r14,%rdi
   f:	e8 82 2d a2 f7       	call   0xf7a22d96
  14:	f6 44 24 21 02       	testb  $0x2,0x21(%rsp)
  19:	75 4e                	jne    0x69
  1b:	41 f7 c7 00 02 00 00 	test   $0x200,%r15d
  22:	74 01                	je     0x25
  24:	fb                   	sti
  25:	bf 01 00 00 00       	mov    $0x1,%edi
* 2a:	e8 d7 6c 2f f7       	call   0xf72f6d06 <-- trapping instruction
  2f:	65 8b 05 d8 72 da 75 	mov    %gs:0x75da72d8(%rip),%eax        # 0x75da730e
  36:	85 c0                	test   %eax,%eax
  38:	74 3f                	je     0x79
  3a:	48                   	rex.W
  3b:	c7                   	.byte 0xc7
  3c:	04 24                	add    $0x24,%al
  3e:	0e                   	(bad)
  3f:	36                   	ss