From: syzbot <syzbot+8ce7f8308d91e6b8bbe2@syzkaller.appspotmail.com>
To: akpm@linux-foundation.org, glider@google.com,
linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org,
linux-mm@kvack.org, syzkaller-bugs@googlegroups.com,
willy@infradead.org
Subject: Re: [syzbot] [fs?] [mm?] KMSAN: uninit-value in ondemand_readahead
Date: Fri, 24 Feb 2023 00:32:50 -0800 [thread overview]
Message-ID: <0000000000008f74e905f56df987@google.com> (raw)
In-Reply-To: <0000000000007dcc0b05e91943c2@google.com>
syzbot has found a reproducer for the following issue on:
HEAD commit: 97e36f4aa06f Revert "sched/core: kmsan: do not instrument ..
git tree: https://github.com/google/kmsan.git master
console output: https://syzkaller.appspot.com/x/log.txt?x=10e46944c80000
kernel config: https://syzkaller.appspot.com/x/.config?x=46c642641b9ef616
dashboard link: https://syzkaller.appspot.com/bug?extid=8ce7f8308d91e6b8bbe2
compiler: Debian clang version 15.0.7, GNU ld (GNU Binutils for Debian) 2.35.2
userspace arch: i386
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=143b8650c80000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=15a22f2cc80000
Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/9931a9627dc6/disk-97e36f4a.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/1aafdb2fd6dc/vmlinux-97e36f4a.xz
kernel image: https://storage.googleapis.com/syzbot-assets/90df5872c7ff/bzImage-97e36f4a.xz
mounted in repro: https://storage.googleapis.com/syzbot-assets/ea75a01297dd/mount_0.gz
IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+8ce7f8308d91e6b8bbe2@syzkaller.appspotmail.com
loop0: detected capacity change from 0 to 16
=====================================================
BUG: KMSAN: uninit-value in ondemand_readahead+0xddf/0x1720 mm/readahead.c:596
ondemand_readahead+0xddf/0x1720 mm/readahead.c:596
page_cache_sync_ra+0x72b/0x760 mm/readahead.c:709
page_cache_sync_readahead include/linux/pagemap.h:1210 [inline]
cramfs_blkdev_read fs/cramfs/inode.c:217 [inline]
cramfs_read+0x611/0x1280 fs/cramfs/inode.c:278
cramfs_lookup+0x1b8/0x870 fs/cramfs/inode.c:767
__lookup_slow+0x528/0x730 fs/namei.c:1685
lookup_slow+0x6a/0xc0 fs/namei.c:1702
walk_component fs/namei.c:1993 [inline]
link_path_walk+0xe9a/0x1620 fs/namei.c:2320
path_openat+0x333/0x5750 fs/namei.c:3710
do_filp_open+0x24d/0x660 fs/namei.c:3741
do_sys_openat2+0x1f0/0x910 fs/open.c:1310
do_sys_open fs/open.c:1326 [inline]
__do_compat_sys_openat fs/open.c:1386 [inline]
__se_compat_sys_openat fs/open.c:1384 [inline]
__ia32_compat_sys_openat+0x2ab/0x330 fs/open.c:1384
do_syscall_32_irqs_on arch/x86/entry/common.c:112 [inline]
__do_fast_syscall_32+0xa2/0x100 arch/x86/entry/common.c:178
do_fast_syscall_32+0x37/0x80 arch/x86/entry/common.c:203
do_SYSENTER_32+0x1f/0x30 arch/x86/entry/common.c:246
entry_SYSENTER_compat_after_hwframe+0x70/0x82
Local variable ra.i created at:
cramfs_blkdev_read fs/cramfs/inode.c:186 [inline]
cramfs_read+0xc0/0x1280 fs/cramfs/inode.c:278
cramfs_lookup+0x1b8/0x870 fs/cramfs/inode.c:767
CPU: 1 PID: 5017 Comm: syz-executor948 Not tainted 6.2.0-syzkaller-81152-g97e36f4aa06f #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/16/2023
=====================================================
next prev parent reply other threads:[~2023-02-24 8:32 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-09-20 10:26 [syzbot] KMSAN: uninit-value in ondemand_readahead syzbot
2023-02-24 8:32 ` syzbot [this message]
2023-02-26 20:38 ` [syzbot] [fs?] [mm?] " Andrew Morton
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