* WARNING in submit_bio_checks
@ 2020-07-11 5:34 syzbot
2020-07-13 10:18 ` Christoph Hellwig
2020-07-16 5:00 ` syzbot
0 siblings, 2 replies; 5+ messages in thread
From: syzbot @ 2020-07-11 5:34 UTC (permalink / raw)
To: andriin, ast, axboe, bpf, daniel, john.fastabend, kafai, kpsingh,
linux-block, linux-kernel, netdev, songliubraving,
syzkaller-bugs, yhs
Hello,
syzbot found the following crash on:
HEAD commit: 9e50b94b Add linux-next specific files for 20200703
git tree: linux-next
console output: https://syzkaller.appspot.com/x/log.txt?x=112aaa1f100000
kernel config: https://syzkaller.appspot.com/x/.config?x=f99cc0faa1476ed6
dashboard link: https://syzkaller.appspot.com/bug?extid=4c50ac32e5b10e4133e1
compiler: gcc (GCC) 10.1.0-syz 20200507
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=1111fb6d100000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=1218fa1f100000
IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: syzbot+4c50ac32e5b10e4133e1@syzkaller.appspotmail.com
------------[ cut here ]------------
Trying to write to read-only block-device nullb0 (partno 0)
WARNING: CPU: 0 PID: 6821 at block/blk-core.c:857 bio_check_ro block/blk-core.c:857 [inline]
WARNING: CPU: 0 PID: 6821 at block/blk-core.c:857 submit_bio_checks+0x1aba/0x1f70 block/blk-core.c:985
Kernel panic - not syncing: panic_on_warn set ...
CPU: 0 PID: 6821 Comm: syz-executor914 Not tainted 5.8.0-rc3-next-20200703-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
__dump_stack lib/dump_stack.c:77 [inline]
dump_stack+0x18f/0x20d lib/dump_stack.c:118
panic+0x2e3/0x75c kernel/panic.c:231
__warn.cold+0x20/0x45 kernel/panic.c:600
report_bug+0x1bd/0x210 lib/bug.c:198
handle_bug+0x38/0x90 arch/x86/kernel/traps.c:235
exc_invalid_op+0x13/0x40 arch/x86/kernel/traps.c:255
asm_exc_invalid_op+0x12/0x20 arch/x86/include/asm/idtentry.h:563
RIP: 0010:bio_check_ro block/blk-core.c:857 [inline]
RIP: 0010:submit_bio_checks+0x1aba/0x1f70 block/blk-core.c:985
Code: 04 00 00 45 8b a4 24 a4 05 00 00 48 8d 74 24 68 48 89 ef e8 b8 21 fe ff 48 c7 c7 e0 ce 91 88 48 89 c6 44 89 e2 e8 08 df c0 fd <0f> 0b 48 b8 00 00 00 00 00 fc ff df 4c 89 ea 48 c1 ea 03 80 3c 02
RSP: 0018:ffffc90001277338 EFLAGS: 00010286
RAX: 0000000000000000 RBX: ffff8880a0cb2240 RCX: 0000000000000000
RDX: ffff8880a8ebc180 RSI: ffffffff815d7d27 RDI: fffff5200024ee59
RBP: ffff8880a03101c0 R08: 0000000000000001 R09: ffff8880ae6318e7
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: ffff8880a03101c8 R14: 0000000000000000 R15: ffff8880a03101e8
submit_bio_noacct+0x89/0x12d0 block/blk-core.c:1198
submit_bio+0x263/0x5b0 block/blk-core.c:1283
submit_bh_wbc+0x685/0x8e0 fs/buffer.c:3105
__block_write_full_page+0x837/0x12e0 fs/buffer.c:1848
block_write_full_page+0x214/0x270 fs/buffer.c:3034
__writepage+0x60/0x170 mm/page-writeback.c:2311
write_cache_pages+0x736/0x11b0 mm/page-writeback.c:2246
generic_writepages mm/page-writeback.c:2337 [inline]
generic_writepages+0xe2/0x150 mm/page-writeback.c:2326
do_writepages+0xec/0x290 mm/page-writeback.c:2352
__filemap_fdatawrite_range+0x2a1/0x380 mm/filemap.c:422
filemap_write_and_wait_range mm/filemap.c:655 [inline]
filemap_write_and_wait_range+0xe1/0x1c0 mm/filemap.c:649
filemap_write_and_wait include/linux/fs.h:2629 [inline]
__sync_blockdev fs/block_dev.c:480 [inline]
sync_blockdev fs/block_dev.c:489 [inline]
__blkdev_put+0x69a/0x890 fs/block_dev.c:1863
blkdev_close+0x8c/0xb0 fs/block_dev.c:1947
__fput+0x33c/0x880 fs/file_table.c:281
task_work_run+0xdd/0x190 kernel/task_work.c:135
exit_task_work include/linux/task_work.h:25 [inline]
do_exit+0xb72/0x2a40 kernel/exit.c:806
do_group_exit+0x125/0x310 kernel/exit.c:904
__do_sys_exit_group kernel/exit.c:915 [inline]
__se_sys_exit_group kernel/exit.c:913 [inline]
__x64_sys_exit_group+0x3a/0x50 kernel/exit.c:913
do_syscall_64+0x60/0xe0 arch/x86/entry/common.c:367
entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x43ee48
Code: Bad RIP value.
RSP: 002b:00007ffdd4c8f808 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 000000000043ee48
RDX: 0000000000000000 RSI: 000000000000003c RDI: 0000000000000000
RBP: 00000000004be648 R08: 00000000000000e7 R09: ffffffffffffffd0
R10: 0000000000000003 R11: 0000000000000246 R12: 0000000000000001
R13: 00000000006d0180 R14: 0000000000000000 R15: 0000000000000000
Kernel Offset: disabled
Rebooting in 86400 seconds..
---
This bug is generated by a bot. It may contain errors.
See https://goo.gl/tpsmEJ for more information about syzbot.
syzbot engineers can be reached at syzkaller@googlegroups.com.
syzbot will keep track of this bug report. See:
https://goo.gl/tpsmEJ#status for how to communicate with syzbot.
syzbot can test patches for this bug, for details see:
https://goo.gl/tpsmEJ#testing-patches
^ permalink raw reply [flat|nested] 5+ messages in thread
* Re: WARNING in submit_bio_checks
2020-07-11 5:34 WARNING in submit_bio_checks syzbot
@ 2020-07-13 10:18 ` Christoph Hellwig
2020-07-13 16:16 ` Eric Biggers
2020-07-16 5:00 ` syzbot
1 sibling, 1 reply; 5+ messages in thread
From: Christoph Hellwig @ 2020-07-13 10:18 UTC (permalink / raw)
To: syzbot
Cc: andriin, ast, axboe, bpf, daniel, john.fastabend, kafai, kpsingh,
linux-block, linux-kernel, netdev, songliubraving,
syzkaller-bugs, yhs
On Fri, Jul 10, 2020 at 10:34:19PM -0700, syzbot wrote:
> Hello,
>
> syzbot found the following crash on:
This is not a crash, but a WARN_ONCE. A pre-existing one that just
slightly changed the printed message recently.
^ permalink raw reply [flat|nested] 5+ messages in thread
* Re: WARNING in submit_bio_checks
2020-07-13 10:18 ` Christoph Hellwig
@ 2020-07-13 16:16 ` Eric Biggers
0 siblings, 0 replies; 5+ messages in thread
From: Eric Biggers @ 2020-07-13 16:16 UTC (permalink / raw)
To: Christoph Hellwig
Cc: syzbot, andriin, ast, axboe, bpf, daniel, john.fastabend, kafai,
kpsingh, linux-block, linux-kernel, netdev, songliubraving,
syzkaller-bugs, yhs
On Mon, Jul 13, 2020 at 11:18:36AM +0100, Christoph Hellwig wrote:
> On Fri, Jul 10, 2020 at 10:34:19PM -0700, syzbot wrote:
> > Hello,
> >
> > syzbot found the following crash on:
>
> This is not a crash, but a WARN_ONCE. A pre-existing one that just
> slightly changed the printed message recently.
>
It doesn't really matter. WARN is for indicating kernel bugs only.
A user-triggable WARN is a bug. Either the bug that makes the WARN
reachable needs to be fixed, or if the WARN is legitimately user-reachable
it needs to be removed or replaced with a proper ratelimited log message.
This one looks legitimately user-reachable, so we could do:
diff --git a/block/blk-core.c b/block/blk-core.c
index d9d632639bd1..354c51ad5c81 100644
--- a/block/blk-core.c
+++ b/block/blk-core.c
@@ -854,8 +854,8 @@ static inline bool bio_check_ro(struct bio *bio, struct hd_struct *part)
if (op_is_flush(bio->bi_opf) && !bio_sectors(bio))
return false;
- WARN_ONCE(1,
- "Trying to write to read-only block-device %s (partno %d)\n",
+ pr_warn_ratelimited(
+ "block: trying to write to read-only block-device %s (partno %d)\n",
bio_devname(bio, b), part->partno);
/* Older lvm-tools actually trigger this */
return false;
We could also show current->comm and current->pid if they would be useful here.
And yes, this is preexisting which is why syzbot has reported this before
(https://syzkaller.appspot.com/bug?id=79eda145ab047a0dc7d03ca5fcb1cf12206eb481).
Just no one has bothered to fix it yet.
- Eric
^ permalink raw reply related [flat|nested] 5+ messages in thread
* Re: WARNING in submit_bio_checks
2020-07-11 5:34 WARNING in submit_bio_checks syzbot
2020-07-13 10:18 ` Christoph Hellwig
@ 2020-07-16 5:00 ` syzbot
1 sibling, 0 replies; 5+ messages in thread
From: syzbot @ 2020-07-16 5:00 UTC (permalink / raw)
To: andriin, ast, axboe, bkkarthik, bpf, daniel, davem, ebiggers,
hch, john.fastabend, kafai, kpsingh, linux-block, linux-fsdevel,
linux-kernel, mcgrof, netdev, songliubraving, syzkaller-bugs,
viro, yhs
syzbot has bisected this issue to:
commit 449325b52b7a6208f65ed67d3484fd7b7184477b
Author: Alexei Starovoitov <ast@kernel.org>
Date: Tue May 22 02:22:29 2018 +0000
umh: introduce fork_usermode_blob() helper
bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=10fc4b00900000
start commit: 9e50b94b Add linux-next specific files for 20200703
git tree: linux-next
final oops: https://syzkaller.appspot.com/x/report.txt?x=12fc4b00900000
console output: https://syzkaller.appspot.com/x/log.txt?x=14fc4b00900000
kernel config: https://syzkaller.appspot.com/x/.config?x=f99cc0faa1476ed6
dashboard link: https://syzkaller.appspot.com/bug?extid=4c50ac32e5b10e4133e1
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=1111fb6d100000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=1218fa1f100000
Reported-by: syzbot+4c50ac32e5b10e4133e1@syzkaller.appspotmail.com
Fixes: 449325b52b7a ("umh: introduce fork_usermode_blob() helper")
For information about bisection process see: https://goo.gl/tpsmEJ#bisection
^ permalink raw reply [flat|nested] 5+ messages in thread
* WARNING in submit_bio_checks
@ 2021-09-03 7:41 Hao Sun
0 siblings, 0 replies; 5+ messages in thread
From: Hao Sun @ 2021-09-03 7:41 UTC (permalink / raw)
To: axboe, linux-block
Cc: andrii, ast, bpf, daniel, john.fastabend, kafai, kpsingh,
linux-kernel, netdev, songliubraving, yhs
Hello,
When using Healer to fuzz the latest Linux kernel, the following crash
was triggered.
HEAD commit: 7d2a07b76933 Linux 5.14
git tree: upstream
console output:
https://drive.google.com/file/d/1g67CqWvvbFRJyFBoHJk59BMQH3UcvNQx/view?usp=sharing
kernel config: https://drive.google.com/file/d/1XD9WYDViQLSXN7RGwH8AGGDvP9JvOghx/view?usp=sharing
C reproducer: https://drive.google.com/file/d/1Mox767TITuZDWxGR8B2RdBH4tAU4bYfq/view?usp=sharing
Syzlang reproducer:
https://drive.google.com/file/d/1pzANwS2DrA6owxrHieLNyKWmUgKOtwVl/view?usp=sharing
If you fix this issue, please add the following tag to the commit:
Reported-by: Hao Sun <sunhao.th@gmail.com>
------------[ cut here ]------------
Trying to write to read-only block-device nullb0 (partno 0)
WARNING: CPU: 1 PID: 11327 at block/blk-core.c:700 bio_check_ro
block/blk-core.c:700 [inline]
WARNING: CPU: 1 PID: 11327 at block/blk-core.c:700
submit_bio_checks+0x1605/0x1a70 block/blk-core.c:813
Modules linked in:
CPU: 1 PID: 11327 Comm: syz-executor Not tainted 5.14.0 #25
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS
1.13.0-1ubuntu1.1 04/01/2014
RIP: 0010:bio_check_ro block/blk-core.c:700 [inline]
RIP: 0010:submit_bio_checks+0x1605/0x1a70 block/blk-core.c:813
Code: 00 00 45 0f b6 a4 24 90 05 00 00 48 8d 74 24 60 48 89 ef e8 8d
54 fe ff 48 c7 c7 e0 b7 de 89 48 89 c6 44 89 e2 e8 ac 9e 1a 05 <0f> 0b
e9 91 f3 ff ff e8 8f fc b1 fd e8 9a d5 5b 05 31 ff 89 c3 89
RSP: 0018:ffffc90004007198 EFLAGS: 00010286
RAX: 0000000000000000 RBX: ffff888100ec6430 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffff88810338d640 RDI: fffff52000800e25
RBP: ffff8881140748c0 R08: ffffffff815d0995 R09: 0000000000000000
R10: 0000000000000005 R11: ffffed10233e3f53 R12: 0000000000000000
R13: ffff8881140748d0 R14: ffff8881083c21c0 R15: ffff888100ec69a4
FS: 0000000000000000(0000) GS:ffff888119f00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000556c5662e990 CR3: 000000000b68e001 CR4: 0000000000770ee0
PKRU: 55555554
Call Trace:
submit_bio_noacct+0x96/0x1460 block/blk-core.c:1028
submit_bio+0x10a/0x460 block/blk-core.c:1105
submit_bh_wbc+0x5eb/0x7f0 fs/buffer.c:3050
__block_write_full_page+0x853/0x13a0 fs/buffer.c:1805
block_write_full_page+0x4f3/0x610 fs/buffer.c:2976
__writepage+0x60/0x180 mm/page-writeback.c:2314
write_cache_pages+0x78e/0x1280 mm/page-writeback.c:2249
generic_writepages mm/page-writeback.c:2340 [inline]
generic_writepages+0xed/0x160 mm/page-writeback.c:2329
do_writepages+0xfa/0x2a0 mm/page-writeback.c:2355
__filemap_fdatawrite_range+0x2aa/0x390 mm/filemap.c:413
filemap_write_and_wait_range mm/filemap.c:686 [inline]
filemap_write_and_wait_range+0x65/0x100 mm/filemap.c:680
filemap_write_and_wait include/linux/fs.h:2897 [inline]
__sync_blockdev+0x84/0xe0 fs/block_dev.c:526
sync_blockdev fs/block_dev.c:535 [inline]
blkdev_put+0x53f/0x720 fs/block_dev.c:1532
blkdev_close+0x8c/0xb0 fs/block_dev.c:1586
__fput+0x288/0x920 fs/file_table.c:280
task_work_run+0xe0/0x1a0 kernel/task_work.c:164
exit_task_work include/linux/task_work.h:32 [inline]
do_exit+0xbe4/0x2e00 kernel/exit.c:825
do_group_exit+0x125/0x340 kernel/exit.c:922
get_signal+0x4d5/0x25a0 kernel/signal.c:2808
arch_do_signal_or_restart+0x2ed/0x1c40 arch/x86/kernel/signal.c:865
handle_signal_work kernel/entry/common.c:148 [inline]
exit_to_user_mode_loop kernel/entry/common.c:172 [inline]
exit_to_user_mode_prepare+0x192/0x2a0 kernel/entry/common.c:209
__syscall_exit_to_user_mode_work kernel/entry/common.c:291 [inline]
syscall_exit_to_user_mode+0x19/0x50 kernel/entry/common.c:302
do_syscall_64+0x42/0xb0 arch/x86/entry/common.c:86
entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x4739cd
Code: Unable to access opcode bytes at RIP 0x4739a3.
RSP: 002b:00007f9d66b2a218 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: 0000000000000000 RBX: 000000000059c0a0 RCX: 00000000004739cd
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 000000000059c0a8
RBP: 000000000059c0a8 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 000000000059c0ac
R13: 00007ffdcc4a841f R14: 00007ffdcc4a85c0 R15: 00007f9d66b2a300
^ permalink raw reply [flat|nested] 5+ messages in thread
end of thread, other threads:[~2021-09-03 7:41 UTC | newest]
Thread overview: 5+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2020-07-11 5:34 WARNING in submit_bio_checks syzbot
2020-07-13 10:18 ` Christoph Hellwig
2020-07-13 16:16 ` Eric Biggers
2020-07-16 5:00 ` syzbot
2021-09-03 7:41 Hao Sun
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.