syzbot


WARNING in netfs_pages_written_back

Status: upstream: reported on 2024/04/26 02:13
Subsystems: netfs
[Documentation on labels]
Reported-by: syzbot+dbc44fd848d570fc1526@syzkaller.appspotmail.com
First crash: 54d, last: 40d
Discussions (1)
Title Replies (including bot) Last reply
[syzbot] [netfs?] WARNING in netfs_pages_written_back 0 (1) 2024/04/26 02:13

Sample crash report:
------------[ cut here ]------------
bad 2 @6 page 0 0
WARNING: CPU: 1 PID: 5324 at fs/netfs/buffered_write.c:654 netfs_pages_written_back+0xe02/0x1320 fs/netfs/buffered_write.c:654
Modules linked in:
CPU: 1 PID: 5324 Comm: syz-executor.1 Not tainted 6.9.0-rc6-syzkaller-00234-g7367539ad4b0 #0
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
RIP: 0010:netfs_pages_written_back+0xe02/0x1320 fs/netfs/buffered_write.c:654
Code: 48 c1 ee 03 80 3c 06 00 0f 85 d0 04 00 00 48 8b 44 24 18 4d 89 f0 48 c7 c7 40 41 22 8b 48 8b b0 28 01 00 00 e8 2f e5 20 ff 90 <0f> 0b 90 90 e9 3c f4 ff ff e8 30 16 5e ff e8 2b af 44 ff 31 ff 41
RSP: 0018:ffffc90003eff530 EFLAGS: 00010282
RAX: 0000000000000000 RBX: ffffea0001932200 RCX: ffffc9000c001000
RDX: 0000000000040000 RSI: ffffffff81513a06 RDI: 0000000000000001
RBP: 0000000000000000 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000002 R12: dffffc0000000000
R13: ffff88805d6fac40 R14: 0000000000000000 R15: ffff88805d6fad38
FS:  0000000000000000(0000) GS:ffff88802c300000(0063) knlGS:00000000f5e8bb40
CS:  0010 DS: 002b ES: 002b CR0: 0000000080050033
CR2: 0000000000000000 CR3: 000000005a216000 CR4: 0000000000350ef0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 netfs_cleanup_buffered_write+0x7a8/0x9b0 fs/netfs/buffered_write.c:727
 netfs_write_terminated+0x3c7/0x910 fs/netfs/output.c:121
 netfs_end_writethrough+0x1a6/0x200 fs/netfs/output.c:468
 netfs_perform_write+0x1a29/0x2690 fs/netfs/buffered_write.c:397
 netfs_buffered_write_iter_locked+0x213/0x2c0 fs/netfs/buffered_write.c:455
 netfs_file_write_iter+0x1e0/0x470 fs/netfs/buffered_write.c:494
 v9fs_file_write_iter+0xa1/0x100 fs/9p/vfs_file.c:407
 call_write_iter include/linux/fs.h:2110 [inline]
 aio_write+0x3bc/0x8d0 fs/aio.c:1639
 __io_submit_one fs/aio.c:2011 [inline]
 io_submit_one+0x11b6/0x1df0 fs/aio.c:2058
 __do_compat_sys_io_submit fs/aio.c:2159 [inline]
 __se_compat_sys_io_submit fs/aio.c:2129 [inline]
 __ia32_compat_sys_io_submit+0x1af/0x390 fs/aio.c:2129
 do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline]
 __do_fast_syscall_32+0x75/0x120 arch/x86/entry/common.c:386
 do_fast_syscall_32+0x32/0x80 arch/x86/entry/common.c:411
 entry_SYSENTER_compat_after_hwframe+0x84/0x8e
RIP: 0023:0xf7299579
Code: b8 01 10 06 03 74 b4 01 10 07 03 74 b0 01 10 08 03 74 d8 01 00 00 00 00 00 00 00 00 00 00 00 00 00 51 52 55 89 e5 0f 34 cd 80 <5d> 5a 59 c3 90 90 90 90 8d b4 26 00 00 00 00 8d b4 26 00 00 00 00
RSP: 002b:00000000f5e8b5ac EFLAGS: 00000292 ORIG_RAX: 00000000000000f8
RAX: ffffffffffffffda RBX: 00000000f5e41000 RCX: 0000000000000001
RDX: 0000000020000700 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
 </TASK>
----------------
Code disassembly (best guess), 2 bytes skipped:
   0:	10 06                	adc    %al,(%rsi)
   2:	03 74 b4 01          	add    0x1(%rsp,%rsi,4),%esi
   6:	10 07                	adc    %al,(%rdi)
   8:	03 74 b0 01          	add    0x1(%rax,%rsi,4),%esi
   c:	10 08                	adc    %cl,(%rax)
   e:	03 74 d8 01          	add    0x1(%rax,%rbx,8),%esi
  1e:	00 51 52             	add    %dl,0x52(%rcx)
  21:	55                   	push   %rbp
  22:	89 e5                	mov    %esp,%ebp
  24:	0f 34                	sysenter
  26:	cd 80                	int    $0x80
* 28:	5d                   	pop    %rbp <-- trapping instruction
  29:	5a                   	pop    %rdx
  2a:	59                   	pop    %rcx
  2b:	c3                   	ret
  2c:	90                   	nop
  2d:	90                   	nop
  2e:	90                   	nop
  2f:	90                   	nop
  30:	8d b4 26 00 00 00 00 	lea    0x0(%rsi,%riz,1),%esi
  37:	8d b4 26 00 00 00 00 	lea    0x0(%rsi,%riz,1),%esi

Crashes (4):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/05/05 14:28 upstream 7367539ad4b0 610f2a54 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream-386 WARNING in netfs_pages_written_back
2024/05/02 09:42 upstream 0106679839f7 3ba885bc .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream-386 WARNING in netfs_pages_written_back
2024/04/25 20:40 upstream e33c4963bf53 8bdc0f22 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream-386 WARNING in netfs_pages_written_back
2024/04/22 02:10 upstream 3b68086599f8 af24b050 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream-386 WARNING in netfs_pages_written_back
* Struck through repros no longer work on HEAD.