WARNING: kobject bug in bind_rdev_to_array

Status: upstream: reported on 2026/08/17 20:56
Reported-by: syzbot+806834e01a827c622207@syzkaller.appspotmail.com
First crash: 12d, last: 1d10h
Similar bugs (1)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-6.6 WARNING: kobject bug in bind_rdev_to_array -1 5 4d05h 32d 0/2 upstream: reported on 2026/07/29 11:17

Sample crash report:
------------[ cut here ]------------
kobject: '(null)' (ffff888074a44060): is not initialized, yet kobject_get() is being called.
WARNING: CPU: 1 PID: 9699 at lib/kobject.c:634 kobject_get lib/kobject.c:632 [inline]
WARNING: CPU: 1 PID: 9699 at lib/kobject.c:634 kobject_add_internal+0x115/0xca0 lib/kobject.c:216
Modules linked in:
CPU: 1 PID: 9699 Comm: syz.6.1258 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:632 [inline]
RIP: 0010:kobject_add_internal+0x115/0xca0 lib/kobject.c:216
Code: b9 00 00 00 00 00 fc ff df 80 3c 08 00 74 08 4c 89 e7 e8 6e 78 b6 f7 49 8b 34 24 48 c7 c7 e0 9d b1 8b 4c 89 e2 e8 0b c6 30 f7 <0f> 0b e9 e5 00 00 00 e8 af 3e 65 f7 b8 fe ff ff ff e9 eb 06 00 00
RSP: 0018:ffffc900061d7808 EFLAGS: 00010246
RAX: 90729a03e4c74000 RBX: ffff888057011878 RCX: 0000000000080000
RDX: ffffc90014948000 RSI: 000000000000b370 RDI: 000000000000b371
RBP: 0000000000000000 R08: ffffc900061d7487 R09: 1ffff92000c3ae90
R10: dffffc0000000000 R11: fffff52000c3ae91 R12: ffff888074a44060
R13: dffffc0000000000 R14: ffff888074a4409c R15: dffffc0000000000
FS:  00007f85481326c0(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f85471eb840 CR3: 000000005f137000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 kobject_add_varg lib/kobject.c:366 [inline]
 kobject_add+0x160/0x230 lib/kobject.c:418
 bind_rdev_to_array+0xb50/0x1260 drivers/md/md.c:2486
 md_add_new_disk+0xe43/0x17b0 drivers/md/md.c:6990
 md_ioctl+0x24f5/0x2880 drivers/md/md.c:7799
 blkdev_ioctl+0x37b/0x740 block/ioctl.c:626
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:870 [inline]
 __se_sys_ioctl+0xfa/0x170 fs/ioctl.c:856
 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: 0033:0x7f854719e159
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:00007f8548132028 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f8547426090 RCX: 00007f854719e159
RDX: 0000200000000420 RSI: 0000000040140921 RDI: 0000000000000008
RBP: 00007f8547235024 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f8547426128 R14: 00007f8547426090 R15: 00007fffca8aa4c8
 </TASK>

Crashes (7):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/08/29 03:53 linux-6.1.y d64a499eea6b 2f52988a .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan WARNING: kobject bug in bind_rdev_to_array
2026/08/29 03:52 linux-6.1.y d64a499eea6b 2f52988a .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan WARNING: kobject bug in bind_rdev_to_array
2026/08/25 06:21 linux-6.1.y 05208478041c 614e416a .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan WARNING: kobject bug in bind_rdev_to_array
2026/08/21 13:02 linux-6.1.y 7e6e67054721 1e72964b .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan WARNING: kobject bug in bind_rdev_to_array
2026/08/21 12:09 linux-6.1.y 7e6e67054721 1e72964b .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan WARNING: kobject bug in bind_rdev_to_array
2026/08/21 02:25 linux-6.1.y 7e6e67054721 1e72964b .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan WARNING: kobject bug in bind_rdev_to_array
2026/08/17 20:56 linux-6.1.y e4f7d8be268e 905244d6 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan WARNING: kobject bug in bind_rdev_to_array
* Struck through repros no longer work on HEAD.