do_last(): ELOOP failure exit should be done after leaving RCU mode

... or we risk seeing a bogus value of d_is_symlink() there. Cc: [email protected] # v4.2+ Signed-off-by: Al Viro <[email protected]>
kyagi · Feb 28, 2016 · 5129fa4 · 5129fa4
1 parent a7f7754
commit 5129fa4
Showing 1 changed file with 4 additions and 5 deletions.
diff --git a/fs/namei.c b/fs/namei.c
@@ -3211,11 +3211,6 @@ static int do_last(struct nameidata *nd,
 	if (unlikely(error))
 		return error;
 
-	if (unlikely(d_is_symlink(path.dentry)) && !(open_flag & O_PATH)) {
-		path_to_nameidata(&path, nd);
-		return -ELOOP;
-	}
-
 	if ((nd->flags & LOOKUP_RCU) || nd->path.mnt != path.mnt) {
 		path_to_nameidata(&path, nd);
 	} else {
@@ -3234,6 +3229,10 @@ static int do_last(struct nameidata *nd,
 		return error;
 	}
 	audit_inode(nd->name, nd->path.dentry, 0);
+	if (unlikely(d_is_symlink(nd->path.dentry)) && !(open_flag & O_PATH)) {
+		error = -ELOOP;
+		goto out;
+	}
 	error = -EISDIR;
 	if ((open_flag & O_CREAT) && d_is_dir(nd->path.dentry))
 		goto out;