syzbot
kernel BUG in ext4_get_group_info
Status:
upstream: reported C repro on 2023/03/19 23:40
Bug presence:
origin:lts-only
[Documentation on labels]
Reported-by: syzbot+84f3fb17cf44e689a0f3@syzkaller.appspotmail.com
First crash: 1226d, last: 1060d
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Bug presence (2)
| Date |
Name |
Commit |
Repro |
Result |
| 2023/05/14 |
linux-6.1.y (ToT) |
bf4ad6fa4e53 |
C
|
[report] kernel BUG in ext4_get_group_info
|
| 2023/05/14 |
upstream (ToT) |
bb7c241fae62 |
C
|
Didn't crash |
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Fix bisection attempts (5)
Sample crash report:
EXT4-fs error (device loop3): ext4_write_end:1344: inode #19: comm syz-executor787: mark_inode_dirty error
------------[ cut here ]------------
kernel BUG at fs/ext4/ext4.h:3331!
invalid opcode: 0000 [#1] PREEMPT SMP KASAN
CPU: 1 PID: 3561 Comm: syz-executor787 Not tainted 6.1.27-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/14/2023
RIP: 0010:ext4_get_group_info+0x399/0x3a0 fs/ext4/ext4.h:3331
Code: 4f ff 8b 74 24 04 48 c7 c7 40 d3 0b 8d 4c 89 f2 e8 2c c9 24 02 43 80 3c 2c 00 0f 85 23 fd ff ff e9 26 fd ff ff e8 47 8f 4f ff <0f> 0b 0f 1f 44 00 00 55 41 57 41 56 41 54 53 48 89 fb 49 bf 00 00
RSP: 0018:ffffc90003bef590 EFLAGS: 00010293
RAX: ffffffff823a3979 RBX: 00000000fffffac6 RCX: ffff888076938000
RDX: 0000000000000000 RSI: 00000000fffffac6 RDI: 0000000000000001
RBP: 0000000000000001 R08: ffffffff823a3649 R09: ffffed100df0573c
R10: 0000000000000000 R11: dffffc0000000001 R12: 1ffff1100fa378cf
R13: dffffc0000000000 R14: ffff88807d1be000 R15: ffff88807d1bc678
FS: 0000000000000000(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007faf8ae71f78 CR3: 000000007d17f000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<TASK>
ext4_mb_load_buddy_gfp+0xc3/0x820 fs/ext4/mballoc.c:1448
ext4_discard_preallocations+0x851/0x1150 fs/ext4/mballoc.c:5021
ext4_release_file+0x16a/0x300 fs/ext4/file.c:166
__fput+0x3b7/0x890 fs/file_table.c:320
task_work_run+0x246/0x300 kernel/task_work.c:179
exit_task_work include/linux/task_work.h:38 [inline]
do_exit+0x6fb/0x2300 kernel/exit.c:869
do_group_exit+0x202/0x2b0 kernel/exit.c:1019
get_signal+0x16f7/0x17d0 kernel/signal.c:2858
arch_do_signal_or_restart+0xb0/0x1a10 arch/x86/kernel/signal.c:869
exit_to_user_mode_loop+0x6a/0x100 kernel/entry/common.c:168
exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:204
__syscall_exit_to_user_mode_work kernel/entry/common.c:286 [inline]
syscall_exit_to_user_mode+0x60/0x270 kernel/entry/common.c:297
do_syscall_64+0x49/0xb0 arch/x86/entry/common.c:86
entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7faf8ae21309
Code: Unable to access opcode bytes at 0x7faf8ae212df.
RSP: 002b:00007faf8adcd2f8 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: 0000000000025000 RBX: 00007faf8aea57a0 RCX: 00007faf8ae21309
RDX: 000000000208e24b RSI: 0000000020000000 RDI: 0000000000000006
RBP: 00007faf8ae7294c R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0030656c69662f2e
R13: 6f6f6c2f7665642f R14: 632e79726f6d656d R15: 00007faf8aea57a8
</TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:ext4_get_group_info+0x399/0x3a0 fs/ext4/ext4.h:3331
Code: 4f ff 8b 74 24 04 48 c7 c7 40 d3 0b 8d 4c 89 f2 e8 2c c9 24 02 43 80 3c 2c 00 0f 85 23 fd ff ff e9 26 fd ff ff e8 47 8f 4f ff <0f> 0b 0f 1f 44 00 00 55 41 57 41 56 41 54 53 48 89 fb 49 bf 00 00
RSP: 0018:ffffc90003bef590 EFLAGS: 00010293
RAX: ffffffff823a3979 RBX: 00000000fffffac6 RCX: ffff888076938000
RDX: 0000000000000000 RSI: 00000000fffffac6 RDI: 0000000000000001
RBP: 0000000000000001 R08: ffffffff823a3649 R09: ffffed100df0573c
R10: 0000000000000000 R11: dffffc0000000001 R12: 1ffff1100fa378cf
R13: dffffc0000000000 R14: ffff88807d1be000 R15: ffff88807d1bc678
FS: 0000000000000000(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000020344000 CR3: 0000000028bbe000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
* Struck through repros no longer work on HEAD.