syzbot


kernel BUG in mb_mark_used

Status: upstream: reported C repro on 2025/03/16 17:45
Bug presence: origin:upstream
[Documentation on labels]
Reported-by: syzbot+111f30c98c5ace9f8e60@syzkaller.appspotmail.com
First crash: 19d, last: 4d22h
Bug presence (2)
Date Name Commit Repro Result
2025/03/18 lts (merge base) c16c81c81336 C [report] kernel BUG in mb_mark_used
2025/03/18 upstream (ToT) 81e4f8d68c66 C [report] kernel BUG in mb_mark_used
Similar bugs (1)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
android-6-1 kernel BUG in mb_mark_used origin:upstream C 1 11d 26d 0/2 upstream: reported C repro on 2025/03/09 09:53
Last patch testing requests (1)
Created Duration User Patch Repo Result
2025/03/31 00:02 6m retest repro android13-5.15-lts report log

Sample crash report:
ext4 filesystem being mounted at /root/file0 supports timestamps until 2038-01-19 (0x7fffffff)
------------[ cut here ]------------
kernel BUG at fs/ext4/mballoc.c:1982!
invalid opcode: 0000 [#1] PREEMPT SMP KASAN
CPU: 0 PID: 293 Comm: syz-executor116 Not tainted 5.15.178-syzkaller-00013-g7d1f9b5c2ff5 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
RIP: 0010:mb_mark_used+0x1402/0x1420 fs/ext4/mballoc.c:1982
Code: 0f 0b e8 d1 c6 83 ff 0f 0b e8 ca c6 83 ff 0f 0b e8 c3 c6 83 ff 0f 0b e8 bc c6 83 ff 0f 0b e8 b5 c6 83 ff 0f 0b e8 ae c6 83 ff <0f> 0b e8 a7 c6 83 ff 0f 0b e8 a0 c6 83 ff 0f 0b 66 2e 0f 1f 84 00
RSP: 0018:ffffc90000967590 EFLAGS: 00010293
RAX: ffffffff81eca602 RBX: 0000000000008000 RCX: ffff88810d060000
RDX: 0000000000000000 RSI: ffffffff80000000 RDI: 0000000000008000
RBP: ffffc90000967650 R08: ffffffff81ec92e3 R09: ffffed1020370e01
R10: 0000000000000000 R11: dffffc0000000001 R12: ffff888101b80000
R13: ffffffff80000000 R14: 0000000080000000 R15: ffffc90000967760
FS:  000055558deb0380(0000) GS:ffff8881f7000000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000400000015000 CR3: 000000011de03000 CR4: 00000000003506b0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 ext4_trim_extent fs/ext4/mballoc.c:6459 [inline]
 ext4_try_to_trim_range+0x6b9/0x11d0 fs/ext4/mballoc.c:6519
 ext4_trim_all_free fs/ext4/mballoc.c:6581 [inline]
 ext4_trim_fs+0xd9b/0x16a0 fs/ext4/mballoc.c:6672
 __ext4_ioctl fs/ext4/ioctl.c:1122 [inline]
 ext4_ioctl+0x21ad/0x5830 fs/ext4/ioctl.c:1276
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:874 [inline]
 __se_sys_ioctl+0x114/0x190 fs/ioctl.c:860
 __x64_sys_ioctl+0x7b/0x90 fs/ioctl.c:860
 x64_sys_call+0x98/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:17
 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: 0033:0x7f50cdad9ef9
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 61 17 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 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffda8ff9e68 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00004000000001c0 RCX: 00007f50cdad9ef9
RDX: 0000400000000b40 RSI: 00000000c0185879 RDI: 0000000000000006
RBP: 0000000000000073 R08: 00007f50cdb53260 R09: 00007f50cdb53260
R10: 00007f50cdb53260 R11: 0000000000000246 R12: 0000000000000073
R13: 00004000000004c0 R14: 0000000000000001 R15: 0000000000000001
 </TASK>
Modules linked in:
---[ end trace c99fc14bc7c0ec3b ]---
RIP: 0010:mb_mark_used+0x1402/0x1420 fs/ext4/mballoc.c:1982
Code: 0f 0b e8 d1 c6 83 ff 0f 0b e8 ca c6 83 ff 0f 0b e8 c3 c6 83 ff 0f 0b e8 bc c6 83 ff 0f 0b e8 b5 c6 83 ff 0f 0b e8 ae c6 83 ff <0f> 0b e8 a7 c6 83 ff 0f 0b e8 a0 c6 83 ff 0f 0b 66 2e 0f 1f 84 00
RSP: 0018:ffffc90000967590 EFLAGS: 00010293
RAX: ffffffff81eca602 RBX: 0000000000008000 RCX: ffff88810d060000
RDX: 0000000000000000 RSI: ffffffff80000000 RDI: 0000000000008000
RBP: ffffc90000967650 R08: ffffffff81ec92e3 R09: ffffed1020370e01
R10: 0000000000000000 R11: dffffc0000000001 R12: ffff888101b80000
R13: ffffffff80000000 R14: 0000000080000000 R15: ffffc90000967760
FS:  000055558deb0380(0000) GS:ffff8881f7000000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000400000015000 CR3: 000000011de03000 CR4: 00000000003506b0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/03/16 17:44 android13-5.15-lts 7d1f9b5c2ff5 e2826670 .config strace log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro #1 (clean fs)] [mounted in repro #2 (clean fs)] [mounted in repro #3 (clean fs)] ci2-android-5-15 kernel BUG in mb_mark_used
* Struck through repros no longer work on HEAD.