Linux-EROFS Archive mirror
 help / color / mirror / Atom feed
From: syzbot <syzbot+6c746eea496f34b3161d@syzkaller.appspotmail.com>
To: chao@kernel.org, huyue2@coolpad.com, jefflexu@linux.alibaba.com,
	 linux-erofs@lists.ozlabs.org, linux-fsdevel@vger.kernel.org,
	 linux-kernel@vger.kernel.org, syzkaller-bugs@googlegroups.com,
	 xiang@kernel.org
Subject: [syzbot] [erofs?] KMSAN: uninit-value in z_erofs_lz4_decompress (2)
Date: Wed, 27 Dec 2023 04:31:24 -0800	[thread overview]
Message-ID: <000000000000321c24060d7cfa1c@google.com> (raw)

Hello,

syzbot found the following issue on:

HEAD commit:    fbafc3e621c3 Merge tag 'for_linus' of git://git.kernel.org..
git tree:       upstream
console+strace: https://syzkaller.appspot.com/x/log.txt?x=11b0a595e80000
kernel config:  https://syzkaller.appspot.com/x/.config?x=e0c7078a6b901aa3
dashboard link: https://syzkaller.appspot.com/bug?extid=6c746eea496f34b3161d
compiler:       Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=169fac19e80000
C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=14aafc81e80000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/1520f7b6daa4/disk-fbafc3e6.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/8b490af009d5/vmlinux-fbafc3e6.xz
kernel image: https://storage.googleapis.com/syzbot-assets/202ca200f4a4/bzImage-fbafc3e6.xz
mounted in repro: https://storage.googleapis.com/syzbot-assets/fcf70b38bafb/mount_0.gz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+6c746eea496f34b3161d@syzkaller.appspotmail.com

loop0: detected capacity change from 0 to 16
erofs: (device loop0): mounted with root inode @ nid 36.
erofs: (device loop0): z_erofs_lz4_decompress_mem: failed to decompress -12 in[46, 4050] out[917]
=====================================================
BUG: KMSAN: uninit-value in hex_dump_to_buffer+0xae9/0x10f0 lib/hexdump.c:194
 hex_dump_to_buffer+0xae9/0x10f0 lib/hexdump.c:194
 print_hex_dump+0x13d/0x3e0 lib/hexdump.c:276
 z_erofs_lz4_decompress_mem fs/erofs/decompressor.c:252 [inline]
 z_erofs_lz4_decompress+0x257e/0x2a70 fs/erofs/decompressor.c:311
 z_erofs_decompress_pcluster fs/erofs/zdata.c:1290 [inline]
 z_erofs_decompress_queue+0x338c/0x6460 fs/erofs/zdata.c:1372
 z_erofs_runqueue+0x36cd/0x3830
 z_erofs_read_folio+0x435/0x810 fs/erofs/zdata.c:1843
 filemap_read_folio+0xce/0x370 mm/filemap.c:2323
 do_read_cache_folio+0x3b4/0x11e0 mm/filemap.c:3691
 read_cache_folio+0x60/0x80 mm/filemap.c:3723
 erofs_bread+0x286/0x6f0 fs/erofs/data.c:46
 erofs_find_target_block fs/erofs/namei.c:103 [inline]
 erofs_namei+0x2fe/0x1790 fs/erofs/namei.c:177
 erofs_lookup+0x100/0x3c0 fs/erofs/namei.c:206
 lookup_one_qstr_excl+0x233/0x520 fs/namei.c:1609
 filename_create+0x2fc/0x6d0 fs/namei.c:3876
 do_mkdirat+0x69/0x800 fs/namei.c:4121
 __do_sys_mkdirat fs/namei.c:4144 [inline]
 __se_sys_mkdirat fs/namei.c:4142 [inline]
 __x64_sys_mkdirat+0xc8/0x120 fs/namei.c:4142
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0x44/0x110 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x63/0x6b

Uninit was created at:
 __alloc_pages+0x9a4/0xe00 mm/page_alloc.c:4591
 alloc_pages_mpol+0x62b/0x9d0 mm/mempolicy.c:2133
 alloc_pages mm/mempolicy.c:2204 [inline]
 folio_alloc+0x1da/0x380 mm/mempolicy.c:2211
 filemap_alloc_folio+0xa5/0x430 mm/filemap.c:974
 do_read_cache_folio+0x163/0x11e0 mm/filemap.c:3655
 read_cache_folio+0x60/0x80 mm/filemap.c:3723
 erofs_bread+0x286/0x6f0 fs/erofs/data.c:46
 erofs_find_target_block fs/erofs/namei.c:103 [inline]
 erofs_namei+0x2fe/0x1790 fs/erofs/namei.c:177
 erofs_lookup+0x100/0x3c0 fs/erofs/namei.c:206
 lookup_one_qstr_excl+0x233/0x520 fs/namei.c:1609
 filename_create+0x2fc/0x6d0 fs/namei.c:3876
 do_mkdirat+0x69/0x800 fs/namei.c:4121
 __do_sys_mkdirat fs/namei.c:4144 [inline]
 __se_sys_mkdirat fs/namei.c:4142 [inline]
 __x64_sys_mkdirat+0xc8/0x120 fs/namei.c:4142
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0x44/0x110 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x63/0x6b

CPU: 1 PID: 5006 Comm: syz-executor342 Not tainted 6.7.0-rc7-syzkaller-00003-gfbafc3e621c3 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/17/2023
=====================================================


---
This report 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 issue. See:
https://goo.gl/tpsmEJ#status for how to communicate with syzbot.

If the report is already addressed, let syzbot know by replying with:
#syz fix: exact-commit-title

If you want syzbot to run the reproducer, reply with:
#syz test: git://repo/address.git branch-or-commit-hash
If you attach or paste a git patch, syzbot will apply it before testing.

If you want to overwrite report's subsystems, reply with:
#syz set subsystems: new-subsystem
(See the list of subsystem names on the web dashboard)

If the report is a duplicate of another one, reply with:
#syz dup: exact-subject-of-another-report

If you want to undo deduplication, reply with:
#syz undup

             reply	other threads:[~2023-12-27 12:31 UTC|newest]

Thread overview: 8+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2023-12-27 12:31 syzbot [this message]
2023-12-27 15:19 ` [PATCH] erofs: avoid debugging output for (de)compressed data Gao Xiang
2023-12-28  1:29   ` Yue Hu
2023-12-28  3:36 ` [syzbot] [erofs?] KMSAN: uninit-value in z_erofs_lz4_decompress (2) Gao Xiang
2023-12-28  4:23   ` syzbot
2023-12-29 11:09 ` [PATCH] erofs: fix uninit-value in z_erofs_lz4_decompress Edward Adam Davis via Linux-erofs
2023-12-31  1:14   ` Gao Xiang
2023-12-31  2:32     ` Edward Adam Davis via Linux-erofs

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=000000000000321c24060d7cfa1c@google.com \
    --to=syzbot+6c746eea496f34b3161d@syzkaller.appspotmail.com \
    --cc=chao@kernel.org \
    --cc=huyue2@coolpad.com \
    --cc=jefflexu@linux.alibaba.com \
    --cc=linux-erofs@lists.ozlabs.org \
    --cc=linux-fsdevel@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=syzkaller-bugs@googlegroups.com \
    --cc=xiang@kernel.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for read-only IMAP folder(s) and NNTP newsgroup(s).