[syzbot] WARNING in z_erofs_lz4_decompress

From: syzbot <syzbot+d8aaffc3719597e8cfb4@syzkaller.appspotmail.com>
To: chao@kernel.org, linux-erofs@lists.ozlabs.org,
	linux-kernel@vger.kernel.org, syzkaller-bugs@googlegroups.com,
	xiang@kernel.org
Subject: [syzbot] WARNING in z_erofs_lz4_decompress
Date: Sat, 23 Oct 2021 19:25:20 -0700	[thread overview]
Message-ID: <000000000000b3586105cf0ff45e@google.com> (raw)

Hello,

syzbot found the following issue on:

HEAD commit:    60e8840126bd Add linux-next specific files for 20211018
git tree:       linux-next
console output: https://syzkaller.appspot.com/x/log.txt?x=125932af300000
kernel config:  https://syzkaller.appspot.com/x/.config?x=4bd44cafcda7632e
dashboard link: https://syzkaller.appspot.com/bug?extid=d8aaffc3719597e8cfb4
compiler:       gcc (Debian 10.2.1-6) 10.2.1 20210110, GNU ld (GNU Binutils for Debian) 2.35.2

Unfortunately, I don't have any reproducer for this issue yet.

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+d8aaffc3719597e8cfb4@syzkaller.appspotmail.com

erofs: (device loop4): z_erofs_lz4_decompress_mem: failed to decompress -4100 in[4096, 0] out[9000]
------------[ cut here ]------------
WARNING: CPU: 1 PID: 9895 at fs/erofs/decompressor.c:230 z_erofs_lz4_decompress_mem fs/erofs/decompressor.c:227 [inline]
WARNING: CPU: 1 PID: 9895 at fs/erofs/decompressor.c:230 z_erofs_lz4_decompress+0x841/0x1400 fs/erofs/decompressor.c:289
Modules linked in:
CPU: 1 PID: 9895 Comm: kworker/u5:3 Not tainted 5.15.0-rc5-next-20211018-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: erofs_unzipd z_erofs_decompressqueue_work
RIP: 0010:z_erofs_lz4_decompress_mem fs/erofs/decompressor.c:230 [inline]
RIP: 0010:z_erofs_lz4_decompress+0x841/0x1400 fs/erofs/decompressor.c:289
Code: e9 03 80 3c 11 00 0f 85 8c 0a 00 00 41 56 48 8b 7d 00 45 89 e9 89 d9 48 c7 c2 20 eb fb 89 48 c7 c6 40 ed fb 89 e8 ee 5d 85 05 <0f> 0b 48 b8 00 00 00 00 00 fc ff df 48 8b 4c 24 08 5f 48 89 ca 48
RSP: 0018:ffffc90001b3f718 EFLAGS: 00010286
RAX: 0000000000000000 RBX: ffffffffffffeffc RCX: 0000000000000000
RDX: ffff8880795b3a00 RSI: ffffffff815ef308 RDI: fffff52000367ed3
RBP: ffffc90001b3f858 R08: 0000000000000063 R09: 0000000000000000
R10: ffffffff815e90de R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000002328 R15: 0000000000000000
FS:  0000000000000000(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b2ef25000 CR3: 000000002b3f7000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 z_erofs_decompress_pcluster.isra.0+0x1389/0x2450 fs/erofs/zdata.c:977
 z_erofs_decompress_queue fs/erofs/zdata.c:1055 [inline]
 z_erofs_decompressqueue_work+0xe0/0x170 fs/erofs/zdata.c:1066
 process_one_work+0x9b2/0x1690 kernel/workqueue.c:2297
 worker_thread+0x658/0x11f0 kernel/workqueue.c:2444
 kthread+0x405/0x4f0 kernel/kthread.c:327
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
 </TASK>

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