syzbot


WARNING in blk_rq_append_bio

Status: fixed on 2021/11/10 00:50
Reported-by: syzbot+1c24e3484e48799b2333@syzkaller.appspotmail.com
Fix commit: cbb749cf377a block: remove an incorrect check from blk_rq_append_bio
First crash: 536d, last: 530d

Cause bisection: introduced by (bisect log) :
commit 393bb12e00580aaa23356504eed38d8f5571153a
Author: Christoph Hellwig <hch@lst.de>
Date: Wed Mar 31 07:30:01 2021 +0000

  block: stop calling blk_queue_bounce for passthrough requests

Crash: WARNING in blk_rq_append_bio (log)
Repro: C syz .config

Sample crash report:
------------[ cut here ]------------
WARNING: CPU: 1 PID: 25 at block/blk-map.c:488 blk_rq_append_bio+0x565/0x680 block/blk-map.c:488
Modules linked in:
CPU: 0 PID: 25 Comm: kworker/u4:1 Not tainted 5.12.0-rc6-next-20210407-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: events_unbound async_run_entry_fn
RIP: 0010:blk_rq_append_bio+0x565/0x680 block/blk-map.c:488
Code: 48 89 fa 48 c1 ea 03 80 3c 02 00 0f 85 de 00 00 00 48 8b 44 24 10 48 89 98 a0 00 00 00 45 31 e4 e9 3f fe ff ff e8 6b 3e bc fd <0f> 0b 41 bc ea ff ff ff e9 2d fe ff ff c7 44 24 08 00 00 00 00 e9
RSP: 0018:ffffc90000dff6d0 EFLAGS: 00010293
RAX: 0000000000000000 RBX: 0000000000000001 RCX: 0000000000000000
RDX: ffff888011cbb900 RSI: ffffffff83b7ea55 RDI: 0000000000000003
RBP: 0000000000000008 R08: 0000000000000000 R09: 0000000000000001
R10: ffffffff83b7e568 R11: 0000000000000000 R12: 0000000000000001
R13: 0000000000000008 R14: ffff88801c86e400 R15: ffff88801c86e400
FS:  0000000000000000(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fb8501cc930 CR3: 0000000023c21000 CR4: 00000000001506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 blk_rq_map_kern+0x5db/0x750 block/blk-map.c:653
 __scsi_execute+0x4c1/0x600 drivers/scsi/scsi_lib.c:224
 scsi_execute_req include/scsi/scsi_device.h:462 [inline]
 read_capacity_10+0x112/0x690 drivers/scsi/sd.c:2442
 sd_read_capacity drivers/scsi/sd.c:2519 [inline]
 sd_revalidate_disk.isra.0+0x206c/0x7c00 drivers/scsi/sd.c:3203
 sd_probe+0x9e5/0x1140 drivers/scsi/sd.c:3459
 really_probe+0x291/0xf60 drivers/base/dd.c:576
 driver_probe_device+0x298/0x410 drivers/base/dd.c:763
 __device_attach_driver+0x203/0x2c0 drivers/base/dd.c:870
 bus_for_each_drv+0x15f/0x1e0 drivers/base/bus.c:431
 __device_attach_async_helper+0x1c9/0x290 drivers/base/dd.c:896
 async_run_entry_fn+0x9d/0x550 kernel/async.c:127
 process_one_work+0x98d/0x1600 kernel/workqueue.c:2275
 worker_thread+0x64c/0x1120 kernel/workqueue.c:2421
 kthread+0x3b1/0x4a0 kernel/kthread.c:292
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294

Crashes (6):
Manager Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Title
ci-upstream-linux-next-kasan-gce-root 2021/04/07 22:36 linux-next 5103a5be098c 6a81331a .config log report syz C WARNING in blk_rq_append_bio
ci-upstream-linux-next-kasan-gce-root 2021/04/12 15:57 linux-next 5df924d19629 bfeda1b1 .config log report info WARNING in blk_rq_append_bio
ci-upstream-linux-next-kasan-gce-root 2021/04/12 09:09 linux-next e99d8a849517 bfeda1b1 .config log report info WARNING in blk_rq_append_bio
ci-upstream-linux-next-kasan-gce-root 2021/04/10 15:12 linux-next e99d8a849517 bfeda1b1 .config log report info WARNING in blk_rq_append_bio
ci-upstream-linux-next-kasan-gce-root 2021/04/08 22:39 linux-next 6145d80cfc62 6a81331a .config log report info WARNING in blk_rq_append_bio
ci-upstream-linux-next-kasan-gce-root 2021/04/07 13:26 linux-next 5103a5be098c 6a81331a .config log report info WARNING in blk_rq_append_bio
* Struck through repros no longer work on HEAD.