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kernel BUG in ext4_mb_release_inode_pa

Status: premoderation: reported syz repro on 2024/12/22 22:32
Bug presence: origin:lts
[Documentation on labels]
Reported-by: syzbot+200cb04958291c7edf0d@syzkaller.appspotmail.com
First crash: 101d, last: 10d
▶ ▼ Bug presence (2)
Date Name Commit Repro Result
2024/12/31 lts (merge base) 9467c49437e9 C [report] kernel BUG in ext4_mb_release_inode_pa
2024/12/31 upstream (ToT) ccb98ccef0e5 C Didn't crash
▶ ▼ Similar bugs (3)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
android-5-10 kernel BUG in ext4_mb_release_inode_pa C 6 20d 151d 0/2 upstream: reported C repro on 2024/11/03 14:27
upstream kernel BUG in ext4_mb_release_inode_pa ext4 syz unreliable error 1 499d 495d 0/28 auto-obsoleted due to no activity on 2024/02/29 10:29
android-6-1 kernel BUG in ext4_mb_release_inode_pa origin:lts C 6 18d 109d 0/2 upstream: reported C repro on 2024/12/15 14:57
▶ ▼ Last patch testing requests (8)
Created Duration User Patch Repo Result
2025/03/24 00:49 13m retest repro android13-5.15-lts report log
2025/03/09 10:58 6m retest repro android13-5.15-lts report log
2025/02/09 00:09 8m retest repro android13-5.15-lts report log
2025/02/09 00:09 6m retest repro android13-5.15-lts report log
2025/02/09 00:09 13m retest repro android13-5.15-lts report log
2025/02/09 00:09 14m retest repro android13-5.15-lts report log
2025/02/09 00:09 11m retest repro android13-5.15-lts report log
2025/01/06 02:09 9m retest repro android13-5.15-lts report log

Sample crash report:
EXT4-fs (loop5): pa ffff888120100498: logic 0, phys. 193, len 32
EXT4-fs error (device loop5): ext4_mb_release_inode_pa:4893: group 0, free 7, pa_free 16
------------[ cut here ]------------
kernel BUG at fs/ext4/mballoc.c:4866!
invalid opcode: 0000 [#1] PREEMPT SMP KASAN
CPU: 0 PID: 396 Comm: syz.5.18 Not tainted 5.15.178-syzkaller-00013-g7d1f9b5c2ff5 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024
RIP: 0010:ext4_mb_release_inode_pa+0xda6/0xdb0 fs/ext4/mballoc.c:4866
Code: 85 ff 48 c7 c7 a0 d9 c9 86 4c 89 f6 48 89 da e8 c0 fb 9a 00 e9 90 f4 ff ff e8 c6 5a 85 ff 0f 0b e8 df e5 f6 02 e8 ba 5a 85 ff <0f> 0b 0f 1f 84 00 00 00 00 00 55 48 89 e5 41 57 41 56 53 49 89 fe
RSP: 0018:ffffc90000cd6700 EFLAGS: 00010293
RAX: ffffffff81eb11f6 RBX: 0000000000000060 RCX: ffff888113e9bb40
RDX: 0000000000000000 RSI: 0000000000000060 RDI: 0000000000000000
RBP: ffffc90000cd6850 R08: ffffffff81eb0708 R09: 0000000000000003
R10: fffff5200019acfc R11: dffffc0000000001 R12: dffffc0000000000
R13: 1ffff9200019acf8 R14: 00000000000000a0 R15: dffffc0000000000
FS:  00007ff20287a6c0(0000) GS:ffff8881f7000000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000400000020000 CR3: 000000012de9c000 CR4: 00000000003506b0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 ext4_mb_discard_group_preallocations+0xbe8/0xe50 fs/ext4/mballoc.c:5012
 ext4_mb_discard_preallocations fs/ext4/mballoc.c:5581 [inline]
 ext4_mb_discard_preallocations_should_retry+0x1b7/0x8b0 fs/ext4/mballoc.c:5602
 ext4_mb_new_blocks+0x35ec/0x48f0 fs/ext4/mballoc.c:5805
 ext4_alloc_branch fs/ext4/indirect.c:340 [inline]
 ext4_ind_map_blocks+0xfd1/0x2830 fs/ext4/indirect.c:635
 ext4_map_blocks+0xa08/0x1c70 fs/ext4/inode.c:675
 _ext4_get_block+0x23b/0x660 fs/ext4/inode.c:816
 ext4_get_block+0x39/0x50 fs/ext4/inode.c:833
 ext4_block_write_begin+0x5ea/0x12a0 fs/ext4/inode.c:1101
 ext4_write_begin+0x6bc/0x13d0
 ext4_da_write_begin+0x4a2/0xc30 fs/ext4/inode.c:2987
 generic_perform_write+0x2de/0x750 mm/filemap.c:3857
 ext4_buffered_write_iter+0x48a/0x610 fs/ext4/file.c:270
 ext4_file_write_iter+0x454/0x1660
 call_write_iter include/linux/fs.h:2206 [inline]
 new_sync_write fs/read_write.c:507 [inline]
 vfs_write+0xd5d/0x1110 fs/read_write.c:594
 ksys_write+0x199/0x2c0 fs/read_write.c:647
 __do_sys_write fs/read_write.c:659 [inline]
 __se_sys_write fs/read_write.c:656 [inline]
 __x64_sys_write+0x7b/0x90 fs/read_write.c:656
 x64_sys_call+0x2f/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:2
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7ff202e08169
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ff20287a038 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007ff203020fa0 RCX: 00007ff202e08169
RDX: 0000000000043451 RSI: 0000400000000200 RDI: 0000000000000007
RBP: 00007ff202e892a0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007ff203020fa0 R15: 00007ffdbb69fcb8
 </TASK>
Modules linked in:
---[ end trace d3b9caeeba78c9ae ]---
RIP: 0010:ext4_mb_release_inode_pa+0xda6/0xdb0 fs/ext4/mballoc.c:4866
Code: 85 ff 48 c7 c7 a0 d9 c9 86 4c 89 f6 48 89 da e8 c0 fb 9a 00 e9 90 f4 ff ff e8 c6 5a 85 ff 0f 0b e8 df e5 f6 02 e8 ba 5a 85 ff <0f> 0b 0f 1f 84 00 00 00 00 00 55 48 89 e5 41 57 41 56 53 49 89 fe
RSP: 0018:ffffc90000cd6700 EFLAGS: 00010293
RAX: ffffffff81eb11f6 RBX: 0000000000000060 RCX: ffff888113e9bb40
RDX: 0000000000000000 RSI: 0000000000000060 RDI: 0000000000000000
RBP: ffffc90000cd6850 R08: ffffffff81eb0708 R09: 0000000000000003
R10: fffff5200019acfc R11: dffffc0000000001 R12: dffffc0000000000
R13: 1ffff9200019acf8 R14: 00000000000000a0 R15: dffffc0000000000
FS:  00007ff20287a6c0(0000) GS:ffff8881f7000000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000400000020000 CR3: 000000012de9c000 CR4: 00000000003506b0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400

Crashes (7):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/02/23 10:30 android13-5.15-lts 7d1f9b5c2ff5 d34966d1 .config console log report syz / log [disk image] [vmlinux] [kernel image] [mounted in repro #1 (corrupt fs)] [mounted in repro #2 (clean fs)] ci2-android-5-15 kernel BUG in ext4_mb_release_inode_pa
2025/01/25 22:43 android13-5.15-lts 829d9f138569 9fbd772e .config console log report syz / log [disk image] [vmlinux] [kernel image] [mounted in repro #1] [mounted in repro #2] ci2-android-5-15 kernel BUG in ext4_mb_release_inode_pa
2025/01/25 21:08 android13-5.15-lts 829d9f138569 9fbd772e .config console log report syz / log [disk image] [vmlinux] [kernel image] [mounted in repro #1] [mounted in repro #2] ci2-android-5-15 kernel BUG in ext4_mb_release_inode_pa
2025/01/24 08:25 android13-5.15-lts 829d9f138569 521b0ce3 .config console log report syz / log [disk image] [vmlinux] [kernel image] [mounted in repro] ci2-android-5-15 kernel BUG in ext4_mb_release_inode_pa
2025/01/24 07:11 android13-5.15-lts 829d9f138569 521b0ce3 .config console log report syz / log [disk image] [vmlinux] [kernel image] [mounted in repro] ci2-android-5-15 kernel BUG in ext4_mb_release_inode_pa
2025/01/23 15:11 android13-5.15-lts 829d9f138569 a44b0418 .config console log report syz / log [disk image] [vmlinux] [kernel image] [mounted in repro] ci2-android-5-15 kernel BUG in ext4_mb_release_inode_pa
2024/12/22 22:31 android13-5.15-lts b4bd207b0380 b4fbdbd4 .config console log report syz / log [disk image] [vmlinux] [kernel image] [mounted in repro] ci2-android-5-15 kernel BUG in ext4_mb_release_inode_pa
* Struck through repros no longer work on HEAD.