syzbot
WARNING in bio_alloc_bioset
Status:
upstream: reported C repro on 2026/09/04 03:34
Bug presence:
origin:lts-only
[Documentation on labels]
Reported-by: syzbot+bb66fed5e80b03b1dd76@syzkaller.appspotmail.com
First crash: 10d, last: 7h00m
Sample crash report:
------------[ cut here ]------------
WARNING: CPU: 0 PID: 5929 at block/bio.c:501 bio_alloc_bioset+0xe10/0x12d0 block/bio.c:501
Modules linked in:
CPU: 0 PID: 5929 Comm: syz.0.18 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
RIP: 0010:bio_alloc_bioset+0xe10/0x12d0 block/bio.c:501
Code: 89 de 81 e6 bf db f6 ff 81 ce 00 20 09 00 e8 57 ca ca fd 48 85 c0 74 69 49 89 c7 e8 9a 27 73 fd e9 0d f7 ff ff e8 90 27 73 fd <0f> 0b e9 58 fa ff ff e8 84 27 73 fd e8 0f 42 ec fc e9 ed fb ff ff
RSP: 0018:ffffc900036f7910 EFLAGS: 00010293
RAX: ffffffff84145ae0 RBX: 0000000000000000 RCX: ffff88807e170000
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: dffffc0000000000 R08: ffff888022440a30 R09: 1ffff110059e4717
R10: dffffc0000000000 R11: ffffed10059e4718 R12: 0000000000069801
R13: ffff888022440a30 R14: 0000000000000001 R15: 0000000000000001
FS: 000055557cf80500(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000200000001000 CR3: 0000000076019000 CR4: 00000000003506f0
Call Trace:
<TASK>
md_super_write+0x11c/0x2f0 drivers/md/md.c:963
md_update_sb+0x1369/0x2310 drivers/md/md.c:2801
state_store+0xbf8/0x1b10 drivers/md/md.c:3122
rdev_attr_store+0x27c/0x420 drivers/md/md.c:3638
kernfs_fop_write_iter+0x3a4/0x520 fs/kernfs/file.c:352
call_write_iter include/linux/fs.h:2018 [inline]
new_sync_write fs/read_write.c:491 [inline]
vfs_write+0x474/0x9a0 fs/read_write.c:584
ksys_write+0x151/0x260 fs/read_write.c:637
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: 0033:0x7fd95299e159
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:00007ffe8e4b6378 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007fd952c25fa0 RCX: 00007fd95299e159
RDX: 000000000000000c RSI: 0000200000000a00 RDI: 0000000000000007
RBP: 00007fd952a35024 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fd952c25fac R14: 00007fd952c25fa0 R15: 00007fd952c25fa0
</TASK>
* Struck through repros no longer work on HEAD.