[syzbot] [fuse?] KMSAN: uninit-value in fuse_fileattr_get

[syzbot <syzbot+7c31755f2cea07838b0c@syzkaller.appspotmail.com>]

Hello,

syzbot found the following issue on:

HEAD commit:    18f7fcd5e69a Linux 6.19-rc8
git tree:       upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=16bafc5a580000
kernel config:  https://syzkaller.appspot.com/x/.config?x=9682a42d8ec8b05c
dashboard link: https://syzkaller.appspot.com/bug?extid=7c31755f2cea07838b0c
compiler:       Debian clang version 21.1.8 (++20251221033036+2078da43e25a-1~exp1~20251221153213.50), Debian LLD 21.1.8
syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=1329b322580000
C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=178a425a580000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/c8e19a1c3a97/disk-18f7fcd5.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/ffdc9733836e/vmlinux-18f7fcd5.xz
kernel image: https://storage.googleapis.com/syzbot-assets/8cdf30f0d2d2/bzImage-18f7fcd5.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+7c31755f2cea07838b0c@syzkaller.appspotmail.com

=====================================================
BUG: KMSAN: uninit-value in fuse_fileattr_get+0xeb4/0x1450 fs/fuse/ioctl.c:517
 fuse_fileattr_get+0xeb4/0x1450 fs/fuse/ioctl.c:517
 vfs_fileattr_get fs/file_attr.c:94 [inline]
 __do_sys_file_getattr fs/file_attr.c:416 [inline]
 __se_sys_file_getattr+0x6cb/0xbd0 fs/file_attr.c:372
 __x64_sys_file_getattr+0xe4/0x150 fs/file_attr.c:372
 x64_sys_call+0x17cd/0x3e70 arch/x86/include/generated/asm/syscalls_64.h:469
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xc9/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Local variable fa.i created at:
 __do_sys_file_getattr fs/file_attr.c:380 [inline]
 __se_sys_file_getattr+0x8c/0xbd0 fs/file_attr.c:372
 __x64_sys_file_getattr+0xe4/0x150 fs/file_attr.c:372

CPU: 1 UID: 0 PID: 6065 Comm: syz.0.18 Not tainted syzkaller #0 PREEMPT(voluntary) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/24/2026
=====================================================


---
This report is generated by a bot. It may contain errors.
See https://goo.gl/tpsmEJ for more information about syzbot.
syzbot engineers can be reached at syzkaller@googlegroups.com.

syzbot will keep track of this issue. See:
https://goo.gl/tpsmEJ#status for how to communicate with syzbot.

If the report is already addressed, let syzbot know by replying with:
#syz fix: exact-commit-title

If you want syzbot to run the reproducer, reply with:
#syz test: git://repo/address.git branch-or-commit-hash
If you attach or paste a git patch, syzbot will apply it before testing.

If you want to overwrite report's subsystems, reply with:
#syz set subsystems: new-subsystem
(See the list of subsystem names on the web dashboard)

If the report is a duplicate of another one, reply with:
#syz dup: exact-subject-of-another-report

If you want to undo deduplication, reply with:
#syz undup