syzbot


kernel BUG at fs/ext4/inode.c:LINE!

Status: fixed on 2021/03/10 01:48
Subsystems: ext4
[Documentation on labels]
Reported-by: syzbot+3622cea378100f45d59f@syzkaller.appspotmail.com
Fix commit: 073861ed77b6 mm: fix VM_BUG_ON(PageTail) and BUG_ON(PageWriteback)
First crash: 1304d, last: 1175d
Cause bisection: introduced by (bisect log) [merge commit]:
commit e51418191f5a741b5f94764798c81bf69dec4806
Author: Linus Torvalds <torvalds@linux-foundation.org>
Date: Fri Aug 7 17:53:02 2020 +0000

  Merge tag 'for-linus-5.9-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip

Crash: kernel BUG at fs/ext4/inode.c:LINE! (log)
Repro: C syz .config
  
Discussions (2)
Title Replies (including bot) Last reply
[PATCH 5.9 000/152] 5.9.12-rc1 review 158 (158) 2020/12/02 17:46
kernel BUG at fs/ext4/inode.c:LINE! 19 (20) 2020/11/25 22:01
Similar bugs (9)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-4.19 kernel BUG at fs/ext4/inode.c:LINE! ext4 C error 145 378d 1252d 0/1 upstream: reported C repro on 2020/10/14 01:19
android-54 kernel BUG at fs/ext4/inode.c:LINE! ext4 C 154 5d14h 1525d 0/2 upstream: reported C repro on 2020/01/14 12:13
android-49 kernel BUG at fs/ext4/inode.c:LINE! C 280 1874d 1804d 0/3 public: reported C repro on 2019/04/11 08:44
linux-4.14 kernel BUG at fs/ext4/inode.c:LINE! ext4 C 11 386d 1180d 0/1 upstream: reported C repro on 2020/12/25 03:51
android-414 kernel BUG at fs/ext4/inode.c:LINE! 1 1949d 1801d 0/1 auto-closed as invalid on 2019/05/15 13:37
android-5-10 kernel BUG in mpage_prepare_extent_to_map C error 254 699d 867d 2/2 fixed on 2022/04/21 04:24
android-5-10 kernel BUG in ext4_writepages C error 5 517d 679d 2/2 fixed on 2022/11/16 18:44
android-44 kernel BUG at fs/ext4/inode.c:LINE! C 110 1891d 1804d 0/2 public: reported C repro on 2019/04/11 08:44
upstream kernel BUG in mpage_prepare_extent_to_map ext4 C done error 145 462d 1023d 0/26 auto-obsoleted due to no activity on 2024/03/07 20:46
Last patch testing requests (2)
Created Duration User Patch Repo Result
2020/09/02 05:13 16m anant.thazhemadam@gmail.com https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master report log
2020/08/27 14:33 16m foxhlchen@gmail.com https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master report log
Fix bisection attempts (2)
Created Duration User Patch Repo Result
2020/11/15 11:59 30m bisect fix upstream job log (0) log
2020/10/16 11:26 32m bisect fix upstream job log (0) log

Sample crash report:
------------[ cut here ]------------
kernel BUG at fs/ext4/inode.c:2598!
invalid opcode: 0000 [#1] PREEMPT SMP KASAN
CPU: 1 PID: 27612 Comm: syz-executor879 Not tainted 5.9.0-rc1-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:mpage_prepare_extent_to_map+0xd34/0xd40 fs/ext4/inode.c:2598
Code: 89 e8 a0 74 9f ff 0f 0b e8 59 81 70 ff 4c 89 e7 48 c7 c6 da a3 07 89 e8 8a 74 9f ff 0f 0b e8 43 81 70 ff 0f 0b e8 3c 81 70 ff <0f> 0b e8 c5 b3 25 06 0f 1f 44 00 00 55 41 57 41 56 41 55 41 54 53
RSP: 0018:ffffc9000a0974d8 EFLAGS: 00010293
RAX: ffffffff820476e4 RBX: 00fffe000000a01f RCX: ffff88808ea5c340
RDX: 0000000000000000 RSI: 000000000000a01f RDI: 000000000000ffff
RBP: ffffea00020d4f80 R08: ffffffff820471e4 R09: fffff9400041a9f1
R10: fffff9400041a9f1 R11: 0000000000000000 R12: ffffea00020d4f80
R13: ffffc9000a0977b0 R14: 1ffffd400041a9f1 R15: dffffc0000000000
FS:  00007f5055f25700(0000) GS:ffff8880ae900000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00000000004ae4b0 CR3: 00000000a2d7f000 CR4: 00000000001506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 ext4_writepages+0xa98/0x3750 fs/ext4/inode.c:2735
 do_writepages+0xda/0x1f0 mm/page-writeback.c:2352
 __filemap_fdatawrite_range+0x2a5/0x350 mm/filemap.c:422
 filemap_write_and_wait_range+0xca/0x160 mm/filemap.c:655
 iomap_dio_rw+0x5a7/0xeb0 fs/iomap/direct-io.c:478
 ext4_dio_read_iter fs/ext4/file.c:77 [inline]
 ext4_file_read_iter+0x544/0x6d0 fs/ext4/file.c:129
 call_read_iter include/linux/fs.h:1876 [inline]
 generic_file_splice_read+0x3c5/0x640 fs/splice.c:312
 do_splice_to fs/splice.c:870 [inline]
 splice_direct_to_actor+0x3bd/0xb60 fs/splice.c:950
 do_splice_direct+0x201/0x340 fs/splice.c:1059
 do_sendfile+0x86d/0x1210 fs/read_write.c:1540
 __do_sys_sendfile64 fs/read_write.c:1601 [inline]
 __se_sys_sendfile64 fs/read_write.c:1587 [inline]
 __x64_sys_sendfile64+0x164/0x1a0 fs/read_write.c:1587
 do_syscall_64+0x31/0x70 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x448bc9
Code: e8 1c e6 ff ff 48 83 c4 18 c3 0f 1f 80 00 00 00 00 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 0f 83 0b 06 fc ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007f5055f24ce8 EFLAGS: 00000246 ORIG_RAX: 0000000000000028
RAX: ffffffffffffffda RBX: 00000000006e4a28 RCX: 0000000000448bc9
RDX: 0000000000000000 RSI: 0000000000000006 RDI: 0000000000000004
RBP: 00000000006e4a20 R08: 0000000000000000 R09: 0000000000000000
R10: 00008400fffffffb R11: 0000000000000246 R12: 00000000006e4a2c
R13: 00007ffdc73a76df R14: 00007f5055f259c0 R15: 20c49ba5e353f7cf
Modules linked in:
---[ end trace aba5fca59eda2183 ]---
RIP: 0010:mpage_prepare_extent_to_map+0xd34/0xd40 fs/ext4/inode.c:2598
Code: 89 e8 a0 74 9f ff 0f 0b e8 59 81 70 ff 4c 89 e7 48 c7 c6 da a3 07 89 e8 8a 74 9f ff 0f 0b e8 43 81 70 ff 0f 0b e8 3c 81 70 ff <0f> 0b e8 c5 b3 25 06 0f 1f 44 00 00 55 41 57 41 56 41 55 41 54 53
RSP: 0018:ffffc9000a0974d8 EFLAGS: 00010293
RAX: ffffffff820476e4 RBX: 00fffe000000a01f RCX: ffff88808ea5c340
RDX: 0000000000000000 RSI: 000000000000a01f RDI: 000000000000ffff
RBP: ffffea00020d4f80 R08: ffffffff820471e4 R09: fffff9400041a9f1
R10: fffff9400041a9f1 R11: 0000000000000000 R12: ffffea00020d4f80
R13: ffffc9000a0977b0 R14: 1ffffd400041a9f1 R15: dffffc0000000000
FS:  00007f5055f25700(0000) GS:ffff8880ae900000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00000000004ae4b0 CR3: 00000000a2d7f000 CR4: 00000000001506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400

Crashes (9):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2020/08/23 07:49 upstream c3d8f220d012 1da71ab0 .config console log report syz C ci-upstream-kasan-gce-smack-root
2020/09/06 20:18 upstream dd9fb9bb3340 abf9ba4f .config console log report syz ci-upstream-kasan-gce-selinux-root
2020/12/30 04:26 upstream 139711f033f6 0fa352f2 .config console log report info ci-upstream-kasan-gce-root
2020/09/07 02:20 upstream a8205e310011 abf9ba4f .config console log report ci-upstream-kasan-gce-smack-root
2020/09/06 18:20 upstream dd9fb9bb3340 abf9ba4f .config console log report ci-upstream-kasan-gce-root
2020/08/23 02:40 upstream c3d8f220d012 1da71ab0 .config console log report ci-upstream-kasan-gce-smack-root
2020/11/23 01:28 upstream d5530d82efc8 0d27f508 .config console log report info ci-qemu-upstream-386
2020/12/24 23:57 net-old 1f45dc220667 c2c1d1dd .config console log report info ci-upstream-net-this-kasan-gce
2020/09/16 10:26 net-old 2e5117ba9f58 18d7d030 .config console log report info ci-upstream-net-this-kasan-gce
* Struck through repros no longer work on HEAD.