[syzbot] [hfs?] KMSAN: uninit-value in hfs_find_1st_rec_by_cnid

From: syzbot
Date: Thu Mar 21 2024 - 05:11:37 EST


Hello,

syzbot found the following issue on:

HEAD commit: a4145ce1e7bc Merge tag 'bcachefs-2024-03-19' of https://ev..
git tree: upstream
console+strace: https://syzkaller.appspot.com/x/log.txt?x=1312764e180000
kernel config: https://syzkaller.appspot.com/x/.config?x=5c1d7ee7e74661a8
dashboard link: https://syzkaller.appspot.com/bug?extid=65f53dd6a0f7ad64c0cb
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=1737d879180000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=15f5c2a5180000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/ce90c7e9c4b9/disk-a4145ce1.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/fc2e82754c55/vmlinux-a4145ce1.xz
kernel image: https://storage.googleapis.com/syzbot-assets/dfc8b656ea07/bzImage-a4145ce1.xz
mounted in repro: https://storage.googleapis.com/syzbot-assets/acef21cf3ab0/mount_0.gz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+65f53dd6a0f7ad64c0cb@xxxxxxxxxxxxxxxxxxxxxxxxx

loop0: detected capacity change from 0 to 1024
=====================================================
BUG: KMSAN: uninit-value in hfs_find_1st_rec_by_cnid+0x27a/0x3f0 fs/hfsplus/bfind.c:78
hfs_find_1st_rec_by_cnid+0x27a/0x3f0 fs/hfsplus/bfind.c:78
__hfsplus_brec_find+0x26f/0x7b0 fs/hfsplus/bfind.c:135
hfsplus_brec_find+0x445/0x970 fs/hfsplus/bfind.c:195
hfsplus_find_attr+0x30c/0x390
hfsplus_listxattr+0x586/0x1a60 fs/hfsplus/xattr.c:708
vfs_listxattr fs/xattr.c:493 [inline]
listxattr+0x1f3/0x6b0 fs/xattr.c:840
path_listxattr fs/xattr.c:864 [inline]
__do_sys_listxattr fs/xattr.c:876 [inline]
__se_sys_listxattr fs/xattr.c:873 [inline]
__x64_sys_listxattr+0x16b/0x2f0 fs/xattr.c:873
do_syscall_64+0xd5/0x1f0
entry_SYSCALL_64_after_hwframe+0x6d/0x75

Uninit was created at:
slab_post_alloc_hook mm/slub.c:3804 [inline]
slab_alloc_node mm/slub.c:3845 [inline]
__do_kmalloc_node mm/slub.c:3965 [inline]
__kmalloc+0x6e4/0x1000 mm/slub.c:3979
kmalloc include/linux/slab.h:632 [inline]
hfsplus_find_init+0x91/0x250 fs/hfsplus/bfind.c:21
hfsplus_listxattr+0x44a/0x1a60 fs/hfsplus/xattr.c:695
vfs_listxattr fs/xattr.c:493 [inline]
listxattr+0x1f3/0x6b0 fs/xattr.c:840
path_listxattr fs/xattr.c:864 [inline]
__do_sys_listxattr fs/xattr.c:876 [inline]
__se_sys_listxattr fs/xattr.c:873 [inline]
__x64_sys_listxattr+0x16b/0x2f0 fs/xattr.c:873
do_syscall_64+0xd5/0x1f0
entry_SYSCALL_64_after_hwframe+0x6d/0x75

CPU: 0 PID: 5013 Comm: syz-executor378 Not tainted 6.8.0-syzkaller-11743-ga4145ce1e7bc #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/29/2024
=====================================================


---
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