syzbot
kernel BUG in ext4_mb_release_inode_pa
Status:
upstream: reported C repro on 2024/12/15 14:57
Bug presence:
origin:lts
[Documentation on labels]
Reported-by: syzbot+17ceeb320d1a7e75cc60@syzkaller.appspotmail.com
First crash: 683d, last: 11d
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Bug presence (2)
| Date |
Name |
Commit |
Repro |
Result |
| 2024/12/17 |
lts (merge base) |
b67dc5c9ade9 |
C
|
[report] kernel BUG in ext4_mb_release_inode_pa
|
| 2024/12/17 |
upstream (ToT) |
5529876063e1 |
C
|
Didn't crash |
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Last patch testing requests (10)
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Fix bisection attempts (3)
Sample crash report:
EXT4-fs (loop0): Remounting filesystem read-only
------------[ cut here ]------------
kernel BUG at fs/ext4/mballoc.c:4867!
invalid opcode: 0000 [#1] PREEMPT SMP KASAN
CPU: 1 PID: 313 Comm: syz-executor103 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/16/2026
RIP: 0010:ext4_mb_release_inode_pa+0xa73/0xa80 fs/ext4/mballoc.c:4867
Code: e2 07 80 c2 03 38 c2 0f 8c 2c fe ff ff 4c 89 f7 89 cb e8 80 24 c8 ff 89 d9 e9 1b fe ff ff e8 84 99 82 ff 0f 0b e8 7d 99 82 ff <0f> 0b 66 2e 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 90 90 90
RSP: 0018:ffffc90000eb6c60 EFLAGS: 00010293
RAX: ffffffff81eed4c3 RBX: 00000000000013ee RCX: ffff8881215bbcc0
RDX: 0000000000000000 RSI: 0000000000000060 RDI: 0000000000000000
RBP: ffffc90000eb6db0 R08: 0000000000000003 R09: 0000000000000004
R10: dffffc0000000000 R11: fffff520001d6da8 R12: 1ffff920001d6da4
R13: dffffc0000000000 R14: 0000000000000060 R15: 0000000000000000
FS: 00007f058959b6c0(0000) GS:ffff8881f6f00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000559e6834cf60 CR3: 0000000122a65000 CR4: 00000000003506a0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<TASK>
ext4_mb_discard_group_preallocations+0xbdb/0xe20 fs/ext4/mballoc.c:5013
ext4_mb_discard_preallocations fs/ext4/mballoc.c:5582 [inline]
ext4_mb_discard_preallocations_should_retry+0x15a/0x5e0 fs/ext4/mballoc.c:5603
ext4_mb_new_blocks+0x2f60/0x4070 fs/ext4/mballoc.c:5806
ext4_alloc_branch fs/ext4/indirect.c:340 [inline]
ext4_ind_map_blocks+0xdd1/0x2040 fs/ext4/indirect.c:635
ext4_map_blocks+0x97a/0x1a80 fs/ext4/inode.c:683
_ext4_get_block+0x1ea/0x540 fs/ext4/inode.c:824
ext4_get_block+0x39/0x50 fs/ext4/inode.c:841
ext4_block_write_begin+0x59b/0x1240 fs/ext4/inode.c:1126
ext4_write_begin+0x614/0xfc0 fs/ext4/ext4_jbd2.h:-1
generic_perform_write+0x32d/0x740 mm/filemap.c:3927
ext4_buffered_write_iter+0x38f/0x690 fs/ext4/file.c:285
ext4_file_write_iter+0x4b2/0x1540 fs/ext4/file.c:-1
call_write_iter include/linux/fs.h:2282 [inline]
new_sync_write fs/read_write.c:491 [inline]
vfs_write+0x5ef/0xd00 fs/read_write.c:584
ksys_write+0x14a/0x260 fs/read_write.c:637
__do_sys_write fs/read_write.c:649 [inline]
__se_sys_write fs/read_write.c:646 [inline]
__x64_sys_write+0x7b/0x90 fs/read_write.c:646
x64_sys_call+0x27b/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:2
do_syscall_x64 arch/x86/entry/common.c:46 [inline]
do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f05895c8239
Code: c0 79 93 eb d5 48 8d 7c 1d 00 eb 99 0f 1f 44 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 73 01 c3 48 c7 c1 d0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f058959b168 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007f058966ee28 RCX: 00007f05895c8239
RDX: 000000000208e24b RSI: 0000200000000040 RDI: 0000000000000005
RBP: 00007f058966ee20 R08: 00007f058959bcdc R09: 0000000000000000
R10: 00007f058959bcdc R11: 0000000000000246 R12: 00007f058966ee2c
R13: 0000000000000006 R14: 00007fff0234f910 R15: 00007fff0234f9f8
</TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:ext4_mb_release_inode_pa+0xa73/0xa80 fs/ext4/mballoc.c:4867
Code: e2 07 80 c2 03 38 c2 0f 8c 2c fe ff ff 4c 89 f7 89 cb e8 80 24 c8 ff 89 d9 e9 1b fe ff ff e8 84 99 82 ff 0f 0b e8 7d 99 82 ff <0f> 0b 66 2e 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 90 90 90
RSP: 0018:ffffc90000eb6c60 EFLAGS: 00010293
RAX: ffffffff81eed4c3 RBX: 00000000000013ee RCX: ffff8881215bbcc0
RDX: 0000000000000000 RSI: 0000000000000060 RDI: 0000000000000000
RBP: ffffc90000eb6db0 R08: 0000000000000003 R09: 0000000000000004
R10: dffffc0000000000 R11: fffff520001d6da8 R12: 1ffff920001d6da4
R13: dffffc0000000000 R14: 0000000000000060 R15: 0000000000000000
FS: 00007f058959b6c0(0000) GS:ffff8881f6f00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000559e6834cf60 CR3: 0000000122a65000 CR4: 00000000003506a0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
* Struck through repros no longer work on HEAD.