[PATCH 5.11 118/601] ovl: fix missing revert_creds() on error path

Greg Kroah-Hartman
2021-05-12T17:02:22Z

From: Dan Carpenter <dan.carpenter@oracle.com>

commit 7b279bbfd2b230c7a210ff8f405799c7e46bbf48 upstream.

Smatch complains about missing that the ovl_override_creds() doesn't
have a matching revert_creds() if the dentry is disconnected. Fix this
by moving the ovl_override_creds() until after the disconnected check.

Fixes: aa3ff3c152ff ("ovl: copy up of disconnected dentries")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
fs/overlayfs/copy_up.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)

--- a/fs/overlayfs/copy_up.c
+++ b/fs/overlayfs/copy_up.c
@@ -932,7 +932,7 @@ static int ovl_copy_up_one(struct dentry
static int ovl_copy_up_flags(struct dentry *dentry, int flags)
{
int err = 0;
- const struct cred *old_cred = ovl_override_creds(dentry->d_sb);
+ const struct cred *old_cred;
bool disconnected = (dentry->d_flags & DCACHE_DISCONNECTED);

/*
@@ -943,6 +943,7 @@ static int ovl_copy_up_flags(struct dent
if (WARN_ON(disconnected && d_is_dir(dentry)))
return -EIO;

+ old_cred = ovl_override_creds(dentry->d_sb);
while (!err) {
struct dentry *next;
struct dentry *parent = NULL;