ovl: port ovl_copyfile() to cred guard

Use the scoped ovl cred guard.

Link: https://patch.msgid.link/20251117-work-ovl-cred-guard-v4-36-b31603935724@kernel.org
Reviewed-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Christian Brauner <brauner@kernel.org>

diff --git a/fs/overlayfs/file.c b/fs/overlayfs/file.c
index 0ab846d8062e0147d94273b368ab36377170eeaf..cbae894572348acb3ba6c2b6e7f84558379110c2 100644 (file)
--- a/fs/overlayfs/file.c
+++ b/fs/overlayfs/file.c
@@ -529,7 +529,6 @@ static loff_t ovl_copyfile(struct file *file_in, loff_t pos_in,
 {
        struct inode *inode_out = file_inode(file_out);
        struct file *realfile_in, *realfile_out;
-       const struct cred *old_cred;
        loff_t ret;
 
        inode_lock(inode_out);
@@ -551,25 +550,25 @@ static loff_t ovl_copyfile(struct file *file_in, loff_t pos_in,
        if (IS_ERR(realfile_in))
                goto out_unlock;
 
-       old_cred = ovl_override_creds(file_inode(file_out)->i_sb);
-       switch (op) {
-       case OVL_COPY:
-               ret = vfs_copy_file_range(realfile_in, pos_in,
-                                         realfile_out, pos_out, len, flags);
-               break;
-
-       case OVL_CLONE:
-               ret = vfs_clone_file_range(realfile_in, pos_in,
-                                          realfile_out, pos_out, len, flags);
-               break;
-
-       case OVL_DEDUPE:
-               ret = vfs_dedupe_file_range_one(realfile_in, pos_in,
-                                               realfile_out, pos_out, len,
-                                               flags);
-               break;
+       with_ovl_creds(file_inode(file_out)->i_sb) {
+               switch (op) {
+               case OVL_COPY:
+                       ret = vfs_copy_file_range(realfile_in, pos_in,
+                                                 realfile_out, pos_out, len, flags);
+                       break;
+
+               case OVL_CLONE:
+                       ret = vfs_clone_file_range(realfile_in, pos_in,
+                                                  realfile_out, pos_out, len, flags);
+                       break;
+
+               case OVL_DEDUPE:
+                       ret = vfs_dedupe_file_range_one(realfile_in, pos_in,
+                                                       realfile_out, pos_out, len,
+                                                       flags);
+                       break;
+               }
        }
-       ovl_revert_creds(old_cred);
 
        /* Update size */
        ovl_file_modified(file_out);