1 files changed, 15 insertions, 16 deletions

diff --git a/fs/open.c b/fs/open.c
index f96eaab280a3..c0a426d5766c 100644
--- a/fs/open.c
+++ b/fs/open.c
@@ -425,30 +425,33 @@ out:
  */
 asmlinkage long sys_faccessat(int dfd, const char __user *filename, int mode)
 {
-        struct cred *cred = current->cred;
+        const struct cred *old_cred;
+        struct cred *override_cred;
         struct path path;
         struct inode *inode;
-        int old_fsuid, old_fsgid;
-        kernel_cap_t uninitialized_var(old_cap);  /* !SECURE_NO_SETUID_FIXUP */
         int res;
 
         if (mode & ~S_IRWXO)    /* where's F_OK, X_OK, W_OK, R_OK? */
                 return -EINVAL;
 
-        old_fsuid = cred->fsuid;
-        old_fsgid = cred->fsgid;
+        override_cred = prepare_creds();
+        if (!override_cred)
+                return -ENOMEM;
 
-        cred->fsuid = cred->uid;
-        cred->fsgid = cred->gid;
+        override_cred->fsuid = override_cred->uid;
+        override_cred->fsgid = override_cred->gid;
 
         if (!issecure(SECURE_NO_SETUID_FIXUP)) {
                 /* Clear the capabilities if we switch to a non-root user */
-                if (current->cred->uid)
-                        old_cap = cap_set_effective(__cap_empty_set);
+                if (override_cred->uid)
+                        cap_clear(override_cred->cap_effective);
                 else
-                        old_cap = cap_set_effective(cred->cap_permitted);
+                        override_cred->cap_effective =
+                                override_cred->cap_permitted;
         }
 
+        old_cred = override_creds(override_cred);
+
         res = user_path_at(dfd, filename, LOOKUP_FOLLOW, &path);
         if (res)
                 goto out;
@@ -485,12 +488,8 @@ asmlinkage long sys_faccessat(int dfd, const char __user *filename, int mode)
 out_path_release:
         path_put(&path);
 out:
-        cred->fsuid = old_fsuid;
-        cred->fsgid = old_fsgid;
-
-        if (!issecure(SECURE_NO_SETUID_FIXUP))
-                cap_set_effective(old_cap);
-
+        revert_creds(old_cred);
+        put_cred(override_cred);
         return res;
 }