From cb184dd19154fc486fa3d9e02afe70a97e54e055 Mon Sep 17 00:00:00 2001 From: Edward Adam Davis Date: Fri, 6 Feb 2026 14:20:28 +0800 Subject: [PATCH] fs: init flags_valid before calling vfs_fileattr_get syzbot reported a uninit-value bug in [1]. Similar to the "*get" context where the kernel's internal file_kattr structure is initialized before calling vfs_fileattr_get(), we should use the same mechanism when using fa. [1] 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] 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 Reported-by: syzbot+7c31755f2cea07838b0c@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=7c31755f2cea07838b0c Tested-by: syzbot+7c31755f2cea07838b0c@syzkaller.appspotmail.com Signed-off-by: Edward Adam Davis Link: https://patch.msgid.link/tencent_B6C4583771D76766D71362A368696EC3B605@qq.com Signed-off-by: Christian Brauner --- fs/file_attr.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/fs/file_attr.c b/fs/file_attr.c index 42721427245a..0e9b4f737546 100644 --- a/fs/file_attr.c +++ b/fs/file_attr.c @@ -376,7 +376,7 @@ SYSCALL_DEFINE5(file_getattr, int, dfd, const char __user *, filename, struct path filepath __free(path_put) = {}; unsigned int lookup_flags = 0; struct file_attr fattr; - struct file_kattr fa; + struct file_kattr fa = { .flags_valid = true }; /* hint only */ int error; BUILD_BUG_ON(sizeof(struct file_attr) < FILE_ATTR_SIZE_VER0);