[syzbot] [ext4?] KMSAN: uninit-value in ext4_inlinedir_to_tree

syzbot
2024-04-29T16:05:32Z

Hello,

syzbot found the following issue on:

HEAD commit: e88c4cfcb7b8 Merge tag 'for-6.9-rc5-tag' of git://git.kern..
git tree: upstream
console+strace: https://syzkaller.appspot.com/x/log.txt?x=12fbc980980000
kernel config: https://syzkaller.appspot.com/x/.config?x=776c05250f36d55c
dashboard link: https://syzkaller.appspot.com/bug?extid=eaba5abe296837a640c0
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=13e2cd27180000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=1741a028980000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/76771e00ba79/disk-e88c4cfc.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/c957ed943a4f/vmlinux-e88c4cfc.xz
kernel image: https://storage.googleapis.com/syzbot-assets/e719306ed8e3/bzImage-e88c4cfc.xz
mounted in repro: https://storage.googleapis.com/syzbot-assets/9d3c2a1fa449/mount_0.gz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+eaba5abe296837a640c0@syzkaller.appspotmail.com

EXT4-fs (loop0): mounted filesystem 00000000-0000-0000-0000-000000000000 r/w without journal. Quota mode: none.
EXT4-fs warning (device loop0): __ext4fs_dirhash:270: inode #12: comm syz-executor253: Siphash requires key
=====================================================
BUG: KMSAN: uninit-value in ext4_inlinedir_to_tree+0xde2/0x15a0 fs/ext4/inline.c:1415
ext4_inlinedir_to_tree+0xde2/0x15a0 fs/ext4/inline.c:1415
ext4_htree_fill_tree+0x1941/0x1cd0 fs/ext4/namei.c:1210
ext4_dx_readdir fs/ext4/dir.c:597 [inline]
ext4_readdir+0x4bbf/0x5b00 fs/ext4/dir.c:142
iterate_dir+0x688/0x870 fs/readdir.c:110
__do_sys_getdents64 fs/readdir.c:409 [inline]
__se_sys_getdents64+0x169/0x530 fs/readdir.c:394
__x64_sys_getdents64+0x96/0xe0 fs/readdir.c:394
x64_sys_call+0x343d/0x3b50 arch/x86/include/generated/asm/syscalls_64.h:218
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xcf/0x1e0 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x77/0x7f

Local variable hinfo created at:
ext4_htree_fill_tree+0x52/0x1cd0 fs/ext4/namei.c:1185
ext4_dx_readdir fs/ext4/dir.c:597 [inline]
ext4_readdir+0x4bbf/0x5b00 fs/ext4/dir.c:142

CPU: 1 PID: 5020 Comm: syz-executor253 Not tainted 6.9.0-rc5-syzkaller-00042-ge88c4cfcb7b8 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024
=====================================================

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