[syzbot] KMSAN: uninit-value in hfs_brec_find

From: syzbot <syzbot+5ce571007a695806e949@syzkaller.appspotmail.com>
To: glider@google.com, linux-fsdevel@vger.kernel.org,
	linux-kernel@vger.kernel.org, syzkaller-bugs@googlegroups.com
Subject: [syzbot] KMSAN: uninit-value in hfs_brec_find
Date: Thu, 08 Dec 2022 00:26:47 -0800	[thread overview]
Message-ID: <00000000000043c9a105ef4cccf7@google.com> (raw)

Hello,

syzbot found the following issue on:

HEAD commit:    30d2727189c5 kmsan: fix memcpy tests
git tree:       https://github.com/google/kmsan.git master
console output: https://syzkaller.appspot.com/x/log.txt?x=15931383880000
kernel config:  https://syzkaller.appspot.com/x/.config?x=a2144983ada8b4f3
dashboard link: https://syzkaller.appspot.com/bug?extid=5ce571007a695806e949
compiler:       clang version 15.0.0 (https://github.com/llvm/llvm-project.git 610139d2d9ce6746b3c617fb3e2f7886272d26ff), GNU ld (GNU Binutils for Debian) 2.35.2
userspace arch: i386

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

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/1e8c2d419c2e/disk-30d27271.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/9e8a728a72a9/vmlinux-30d27271.xz
kernel image: https://storage.googleapis.com/syzbot-assets/89f71c80c707/bzImage-30d27271.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+5ce571007a695806e949@syzkaller.appspotmail.com

hfs: keylen 9474 too large
=====================================================
BUG: KMSAN: uninit-value in hfs_brec_find+0x671/0x9b0 fs/hfs/bfind.c:141
 hfs_brec_find+0x671/0x9b0 fs/hfs/bfind.c:141
 hfs_brec_read+0x3b/0x190 fs/hfs/bfind.c:165
 hfs_cat_find_brec+0xfb/0x450 fs/hfs/catalog.c:194
 hfs_fill_super+0x1f49/0x2400 fs/hfs/super.c:419
 mount_bdev+0x508/0x840 fs/super.c:1401
 hfs_mount+0x49/0x60 fs/hfs/super.c:456
 legacy_get_tree+0x10c/0x280 fs/fs_context.c:610
 vfs_get_tree+0xa1/0x500 fs/super.c:1531
 do_new_mount+0x694/0x1580 fs/namespace.c:3040
 path_mount+0x71a/0x1eb0 fs/namespace.c:3370
 do_mount fs/namespace.c:3383 [inline]
 __do_sys_mount fs/namespace.c:3591 [inline]
 __se_sys_mount+0x734/0x840 fs/namespace.c:3568
 __ia32_sys_mount+0xdf/0x140 fs/namespace.c:3568
 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+0x33/0x70 arch/x86/entry/common.c:203
 do_SYSENTER_32+0x1b/0x20 arch/x86/entry/common.c:246
 entry_SYSENTER_compat_after_hwframe+0x70/0x82

Local variable fd created at:
 hfs_fill_super+0x5e/0x2400 fs/hfs/super.c:381
 mount_bdev+0x508/0x840 fs/super.c:1401

CPU: 0 PID: 5557 Comm: syz-executor.2 Not tainted 6.1.0-rc8-syzkaller-64144-g30d2727189c5 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/26/2022
=====================================================

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