syzbot


WARNING in iov_iter_revert

Status: upstream: reported C repro on 2023/06/28 09:07
Bug presence: origin:lts-only
[Documentation on labels]
Reported-by: syzbot+fc9f9c0005eaccca8f3a@syzkaller.appspotmail.com
First crash: 333d, last: 317d
Fix commit to backport (bisect log) :
tree: upstream
commit aa3dbde878961dd333cdd3c326b93e6c84a23ed4
Author: David Howells <dhowells@redhat.com>
Date: Mon May 22 13:49:54 2023 +0000

  splice: Make splice from an O_DIRECT fd use copy_splice_read()

  
Bug presence (2)
Date Name Commit Repro Result
2023/07/14 linux-5.15.y (ToT) d54cfc420586 C [report] WARNING in iov_iter_revert
2023/07/14 upstream (ToT) 4b810bf037e5 C Didn't crash
Similar bugs (5)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream WARNING in iov_iter_revert net C 74 2138d 2204d 8/26 fixed on 2018/08/07 13:43
upstream WARNING in iov_iter_revert (2) serial C done 9 1193d 1194d 20/26 fixed on 2021/04/09 19:46
linux-6.1 WARNING in iov_iter_revert origin:lts-only C done 1 232d 286d 0/3 upstream: reported C repro on 2023/08/13 18:12
upstream WARNING in iov_iter_revert (4) ntfs3 C done error 4 300d 353d 0/26 auto-obsoleted due to no activity on 2023/11/08 23:39
upstream WARNING in iov_iter_revert (3) ntfs3 C error error 26 489d 547d 0/26 auto-obsoleted due to no activity on 2023/05/23 03:07
Fix bisection attempts (1)
Created Duration User Patch Repo Result
2023/09/16 02:01 4h37m fix candidate upstream job log (1)

Sample crash report:
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 11 15 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 c0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffe390acd58 EFLAGS: 00000246 ORIG_RAX: 0000000000000028
RAX: ffffffffffffffda RBX: 0000000000000002 RCX: 00007fbd24f63a09
RDX: 0000000000000000 RSI: 0000000000000004 RDI: 0000000000000004
RBP: 00007ffe390acd80 R08: 0000000000000002 R09: 00007ffe390acd90
R10: 0000000100000000 R11: 0000000000000246 R12: 0000000000000005
R13: 00007ffe390acdc0 R14: 00007ffe390acda0 R15: 0000000000000001
 </TASK>
------------[ cut here ]------------
WARNING: CPU: 1 PID: 3507 at lib/iov_iter.c:1097 iov_iter_revert+0x36e/0x6d0
Modules linked in:
CPU: 1 PID: 3507 Comm: syz-executor170 Not tainted 5.15.118-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/27/2023
RIP: 0010:iov_iter_revert+0x36e/0x6d0 lib/iov_iter.c:1097
Code: 80 3c 30 00 48 8b 5c 24 28 74 08 48 89 df e8 79 a5 c4 fd 4c 89 2b 48 83 c4 50 5b 41 5c 41 5d 41 5e 41 5f 5d c3 e8 e2 48 7b fd <0f> 0b eb e8 4d 8d 75 18 4c 89 f0 48 c1 e8 03 80 3c 28 00 74 08 4c
RSP: 0018:ffffc90002d4f820 EFLAGS: 00010293
RAX: ffffffff8404b16e RBX: ffffffffffff1000 RCX: ffff888024dfbb80
RDX: 0000000000000000 RSI: ffffffffffff1000 RDI: 000000007ffff000
RBP: 1ffff920005a9f3b R08: ffffffff8404ae39 R09: ffff88801ac3100a
R10: 0000000000000000 R11: dffffc0000000001 R12: 1ffff920005a9f32
R13: ffffc90002d4f980 R14: 0000000000000000 R15: ffffc90002d4f980
FS:  0000555555d3d300(0000) GS:ffff8880b9b00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fbd24ff5138 CR3: 0000000019b1a000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 generic_file_read_iter+0x338/0x460 mm/filemap.c:2769
 call_read_iter include/linux/fs.h:2097 [inline]
 generic_file_splice_read+0x4ad/0x790 fs/splice.c:311
 do_splice_to fs/splice.c:796 [inline]
 splice_direct_to_actor+0x448/0xc10 fs/splice.c:870
 do_splice_direct+0x285/0x3d0 fs/splice.c:979
 do_sendfile+0x625/0xff0 fs/read_write.c:1249
 __do_sys_sendfile64 fs/read_write.c:1317 [inline]
 __se_sys_sendfile64+0x178/0x1e0 fs/read_write.c:1303
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x61/0xcb
RIP: 0033:0x7fbd24f63a09
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 11 15 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 c0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffe390acd58 EFLAGS: 00000246 ORIG_RAX: 0000000000000028
RAX: ffffffffffffffda RBX: 0000000000000002 RCX: 00007fbd24f63a09
RDX: 0000000000000000 RSI: 0000000000000004 RDI: 0000000000000004
RBP: 00007ffe390acd80 R08: 0000000000000002 R09: 00007ffe390acd90
R10: 0000000100000000 R11: 0000000000000246 R12: 0000000000000005
R13: 00007ffe390acdc0 R14: 00007ffe390acda0 R15: 0000000000000001
 </TASK>
----------------
Code disassembly (best guess):
   0:	28 00                	sub    %al,(%rax)
   2:	00 00                	add    %al,(%rax)
   4:	75 05                	jne    0xb
   6:	48 83 c4 28          	add    $0x28,%rsp
   a:	c3                   	retq
   b:	e8 11 15 00 00       	callq  0x1521
  10:	90                   	nop
  11:	48 89 f8             	mov    %rdi,%rax
  14:	48 89 f7             	mov    %rsi,%rdi
  17:	48 89 d6             	mov    %rdx,%rsi
  1a:	48 89 ca             	mov    %rcx,%rdx
  1d:	4d 89 c2             	mov    %r8,%r10
  20:	4d 89 c8             	mov    %r9,%r8
  23:	4c 8b 4c 24 08       	mov    0x8(%rsp),%r9
  28:	0f 05                	syscall
* 2a:	48 3d 01 f0 ff ff    	cmp    $0xfffffffffffff001,%rax <-- trapping instruction
  30:	73 01                	jae    0x33
  32:	c3                   	retq
  33:	48 c7 c1 c0 ff ff ff 	mov    $0xffffffffffffffc0,%rcx
  3a:	f7 d8                	neg    %eax
  3c:	64 89 01             	mov    %eax,%fs:(%rcx)
  3f:	48                   	rex.W

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2023/06/28 09:06 linux-5.15.y f67653019430 4cd5bb25 .config console log report syz C [disk image] [vmlinux] [kernel image] [mounted in repro] ci2-linux-5-15-kasan WARNING in iov_iter_revert
* Struck through repros no longer work on HEAD.