syzbot


WARNING in md_alloc

Status: upstream: reported C repro on 2024/07/04 22:03
Bug presence: origin:lts-only
[Documentation on labels]
Reported-by: syzbot+8ecba5ad1880c82079ac@syzkaller.appspotmail.com
First crash: 704d, last: 12h32m
Bug presence (2)
Date Name Commit Repro Result
2024/07/05 linux-5.15.y (ToT) 4878aadf2d15 C [report] WARNING in md_alloc
2024/07/05 upstream (ToT) 661e504db04c C Didn't crash
Similar bugs (2)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-4.19 WARNING in md_alloc -1 2 1781d 1782d 0/1 auto-closed as invalid on 2021/11/20 23:35
upstream WARNING in md_alloc block -1 1 1789d 1785d 0/29 auto-closed as invalid on 2021/11/12 15:56
Last patch testing requests (10)
Created Duration User Patch Repo Result
2026/05/24 09:13 16m retest repro linux-5.15.y report log
2026/05/07 10:52 22m retest repro linux-5.15.y report log
2026/05/07 10:52 16m retest repro linux-5.15.y report log
2026/04/11 08:46 11m retest repro linux-5.15.y report log
2026/04/11 08:46 16m retest repro linux-5.15.y report log
2026/04/11 08:46 24m retest repro linux-5.15.y report log
2026/03/15 01:03 9m retest repro linux-5.15.y error
2026/02/25 00:36 17m retest repro linux-5.15.y report log
2026/02/25 00:36 9m retest repro linux-5.15.y report log
2026/01/30 21:44 13m retest repro linux-5.15.y report log
Fix bisection attempts (1)
Created Duration User Patch Repo Result
2024/07/12 00:34 8h34m fix candidate upstream OK (1) job log
marked invalid by nogikh@google.com

Sample crash report:
RBP: 00007f614bcefd6f R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000003 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f614bed3128 R14: 00007f614bed3090 R15: 00007ffda8c53088
 </TASK>
kobject_add_internal failed for md2 with -EEXIST, don't try to register things with the same name in the same directory.
------------[ cut here ]------------
WARNING: CPU: 0 PID: 5269 at block/genhd.c:547 device_add_disk+0x76b/0xd40 block/genhd.c:545
Modules linked in:
CPU: 0 PID: 5269 Comm: syz.4.311 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
RIP: 0010:device_add_disk+0x76b/0xd40 block/genhd.c:547
Code: b9 00 00 00 00 00 fc ff df 0f b6 04 08 84 c0 0f 85 b0 04 00 00 8b 33 48 c7 c7 a0 e4 8f 8c e8 bc 56 37 00 eb 05 e8 b5 45 ab fd <0f> 0b 41 bf 01 00 00 00 44 89 f8 48 83 c4 70 5b 41 5c 41 5d 41 5e
RSP: 0018:ffffc9000340f690 EFLAGS: 00010293
RAX: ffffffff83ce033b RBX: ffff888059505800 RCX: ffff88807cc1d940
RDX: 0000000000000000 RSI: 0000000000000009 RDI: 0000000000000103
RBP: 0000000000000009 R08: ffff88805bed807b R09: 1ffff1100b7db00f
R10: dffffc0000000000 R11: ffffed100b7db010 R12: ffff88805bed8040
R13: 1ffff1100b2a0b00 R14: dffffc0000000000 R15: 00000000ffffffef
FS:  00007f614b29a6c0(0000) GS:ffff8880b9000000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f6879be3540 CR3: 0000000059e78000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 add_disk include/linux/genhd.h:200 [inline]
 md_alloc+0x809/0xc00 drivers/md/md.c:5782
 blk_probe_dev block/genhd.c:685 [inline]
 blk_request_module+0x26e/0x290 block/genhd.c:-1
 blkdev_get_no_open+0x38/0x1d0 block/bdev.c:740
 blkdev_get_by_dev+0x77/0xa60 block/bdev.c:807
 blkdev_open+0x12d/0x2c0 block/fops.c:466
 do_dentry_open+0x7ff/0xf80 fs/open.c:826
 do_open fs/namei.c:3616 [inline]
 path_openat+0x26f5/0x2fa0 fs/namei.c:3750
 do_filp_open+0x1e2/0x410 fs/namei.c:3777
 do_sys_openat2+0x150/0x4b0 fs/open.c:1255
 do_sys_open fs/open.c:1271 [inline]
 __do_sys_openat fs/open.c:1287 [inline]
 __se_sys_openat fs/open.c:1282 [inline]
 __x64_sys_openat+0x135/0x160 fs/open.c:1282
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f614bc59e59
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 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 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f614b29a028 EFLAGS: 00000246 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007f614bed3090 RCX: 00007f614bc59e59
RDX: 0000000000000000 RSI: 0000200000000a80 RDI: ffffffffffffff9c
RBP: 00007f614bcefd6f R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000003 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f614bed3128 R14: 00007f614bed3090 R15: 00007ffda8c53088
 </TASK>

Crashes (7):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/06/09 02:20 linux-5.15.y dc027a595035 656e94c6 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in md_alloc
2025/06/17 16:47 linux-5.15.y 1c700860e8bc cfebc887 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in md_alloc
2025/06/17 15:56 linux-5.15.y 1c700860e8bc cfebc887 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in md_alloc
2025/06/17 15:02 linux-5.15.y 1c700860e8bc cfebc887 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in md_alloc
2024/08/01 08:36 linux-5.15.y 7e89efd3ae1c 1e9c4cf3 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in md_alloc
2024/07/04 22:02 linux-5.15.y 4878aadf2d15 3f2748a3 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in md_alloc
2025/02/19 08:16 linux-5.15.y c16c81c81336 9a14138f .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 WARNING in md_alloc
* Struck through repros no longer work on HEAD.