[PATCH] fs/stat.c: avoid harmless garbage value problem in vfs_statx_path()

From: Su Hui
Date: Sat Jan 18 2025 - 22:00:11 EST


Clang static checker(scan-build) warning:
fs/stat.c:287:21: warning: The left expression of the compound assignment is
an uninitialized value. The computed value will also be garbage.
287 | stat->result_mask |= STATX_MNT_ID_UNIQUE;
| ~~~~~~~~~~~~~~~~~ ^
fs/stat.c:290:21: warning: The left expression of the compound assignment is
an uninitialized value. The computed value will also be garbage.
290 | stat->result_mask |= STATX_MNT_ID;

When vfs_getattr() failed because of security_inode_getattr(), 'stat' is
uninitialized. In this case, there is a harmless garbage problem in
vfs_statx_path(). It's better to return error directly when
vfs_getattr() failed, avoiding garbage value and more clearly.

Signed-off-by: Su Hui <suhui@xxxxxxxxxxxx>
---
fs/stat.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/fs/stat.c b/fs/stat.c
index 0870e969a8a0..14eb3d01d98a 100644
--- a/fs/stat.c
+++ b/fs/stat.c
@@ -281,6 +281,8 @@ static int vfs_statx_path(struct path *path, int flags, struct kstat *stat,
u32 request_mask)
{
int error = vfs_getattr(path, stat, request_mask, flags);
+ if (error)
+ return error;

if (request_mask & STATX_MNT_ID_UNIQUE) {
stat->mnt_id = real_mount(path->mnt)->mnt_id_unique;
@@ -302,7 +304,7 @@ static int vfs_statx_path(struct path *path, int flags, struct kstat *stat,
if (S_ISBLK(stat->mode))
bdev_statx(path, stat, request_mask);

- return error;
+ return 0;
}

static int vfs_statx_fd(int fd, int flags, struct kstat *stat,
--
2.30.2