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

syzbot
2024-09-23T07:44:24Z

Hello,

syzbot found the following issue on:

HEAD commit: af9c191ac2a0 Merge tag 'trace-ring-buffer-v6.12' of git://..
git tree: upstream
console+strace: https://syzkaller.appspot.com/x/log.txt?x=1705c107980000
kernel config: https://syzkaller.appspot.com/x/.config?x=547de13ee0a4d284
dashboard link: https://syzkaller.appspot.com/bug?extid=18dd03a3fcf0ffe27da0
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=1085c107980000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=16aa9c27980000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/2fd24309dcaf/disk-af9c191a.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/37cd070c7ff6/vmlinux-af9c191a.xz
kernel image: https://storage.googleapis.com/syzbot-assets/71a3466b8e96/bzImage-af9c191a.xz
mounted in repro: https://storage.googleapis.com/syzbot-assets/28d1a4936640/mount_0.gz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+18dd03a3fcf0ffe27da0@syzkaller.appspotmail.com

loop0: detected capacity change from 0 to 64
=====================================================
BUG: KMSAN: uninit-value in hfs_iget+0x1be/0x240 fs/hfs/inode.c:403
hfs_iget+0x1be/0x240 fs/hfs/inode.c:403
hfs_lookup+0x2f3/0x3d0 fs/hfs/dir.c:37
lookup_one_qstr_excl+0x238/0x530 fs/namei.c:1633
do_unlinkat+0x2c5/0xe10 fs/namei.c:4521
__do_sys_unlinkat fs/namei.c:4576 [inline]
__se_sys_unlinkat fs/namei.c:4569 [inline]
__x64_sys_unlinkat+0x17a/0x220 fs/namei.c:4569
x64_sys_call+0x2c7a/0x3ba0 arch/x86/include/generated/asm/syscalls_64.h:264
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xcd/0x1e0 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x77/0x7f

Local variable rec created at:
hfs_lookup+0x43/0x3d0 fs/hfs/dir.c:23
lookup_one_qstr_excl+0x238/0x530 fs/namei.c:1633

CPU: 1 UID: 0 PID: 5180 Comm: syz-executor419 Not tainted 6.11.0-syzkaller-08829-gaf9c191ac2a0 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024
=====================================================

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