WARNING: kobject bug in bind_rdev_to_array

Status: upstream: reported on 2026/07/29 11:17
Reported-by: syzbot+05bc4b41d4c2626afb81@syzkaller.appspotmail.com
First crash: 30d, last: 2d10h
Similar bugs (1)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-6.1 WARNING: kobject bug in bind_rdev_to_array -1 5 3d12h 10d 0/3 upstream: reported on 2026/08/17 20:56

Sample crash report:
------------[ cut here ]------------
kobject: '(null)' (ffff88807b214060): is not initialized, yet kobject_get() is being called.
WARNING: CPU: 0 PID: 6053 at lib/kobject.c:642 kobject_get lib/kobject.c:640 [inline]
WARNING: CPU: 0 PID: 6053 at lib/kobject.c:642 kobject_add_internal+0x115/0xc90 lib/kobject.c:225
Modules linked in:
CPU: 0 PID: 6053 Comm: syz.0.49 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
RIP: 0010:kobject_get lib/kobject.c:640 [inline]
RIP: 0010:kobject_add_internal+0x115/0xc90 lib/kobject.c:225
Code: b9 00 00 00 00 00 fc ff df 80 3c 08 00 74 08 4c 89 e7 e8 fe 86 64 f7 49 8b 34 24 48 c7 c7 60 76 ea 8b 4c 89 e2 e8 2b d6 d5 f6 <0f> 0b e9 e5 00 00 00 e8 5f 09 0c f7 b8 fe ff ff ff e9 f0 06 00 00
RSP: 0018:ffffc900050c78c8 EFLAGS: 00010246
RAX: a8fe20c80ebddd00 RBX: ffff888024bd1878 RCX: 0000000000080000
RDX: ffffc9000e22f000 RSI: 00000000000091d9 RDI: 00000000000091da
RBP: 0000000000000000 R08: ffffc900050c74c7 R09: 1ffff92000a18e98
R10: dffffc0000000000 R11: fffff52000a18e99 R12: ffff88807b214060
R13: dffffc0000000000 R14: ffff88807b21409c R15: dffffc0000000000
FS:  00007f59678116c0(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000110c43115e CR3: 0000000025d8b000 CR4: 00000000003506f0
Call Trace:
 <TASK>
 kobject_add_varg lib/kobject.c:374 [inline]
 kobject_add+0x164/0x240 lib/kobject.c:426
 bind_rdev_to_array+0xb4e/0x1260 drivers/md/md.c:2483
 md_add_new_disk+0xe2e/0x17a0 drivers/md/md.c:6995
 md_ioctl+0x214c/0x24d0 drivers/md/md.c:7809
 blkdev_ioctl+0x5b2/0x730 block/ioctl.c:639
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:871 [inline]
 __se_sys_ioctl+0xfd/0x170 fs/ioctl.c:857
 do_syscall_x64 arch/x86/entry/common.c:46 [inline]
 do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:76
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f596699e0d9
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:00007f5967811028 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f5966c26090 RCX: 00007f596699e0d9
RDX: 0000200000000420 RSI: 0000000040140921 RDI: 0000000000000004
RBP: 00007f5966a35024 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f5966c26128 R14: 00007f5966c26090 R15: 00007ffec3e67598
 </TASK>

Crashes (5):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/08/26 08:51 linux-6.6.y dc6160265ffc 6a91adb4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING: kobject bug in bind_rdev_to_array
2026/08/24 15:58 linux-6.6.y dc6160265ffc b55bd4c3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING: kobject bug in bind_rdev_to_array
2026/08/19 08:42 linux-6.6.y d27334b2888c 1e72964b .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING: kobject bug in bind_rdev_to_array
2026/07/31 06:27 linux-6.6.y a1153c0deb44 aaffb173 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING: kobject bug in bind_rdev_to_array
2026/07/29 11:16 linux-6.6.y c5596480c50e 19622d9d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING: kobject bug in bind_rdev_to_array
* Struck through repros no longer work on HEAD.