X-Git-Url: http://plrg.eecs.uci.edu/git/?a=blobdiff_plain;f=fs%2Fnamei.c;h=0b0acba72a715aaa4ba22c6241c2ed3b10183121;hb=16d185eee470cf2dc3e909a59132893abfdd4b11;hp=209ca7737cb2207ef020e90d159ae8f605c7de0a;hpb=cf5ba83bb248452b5b320d8f2ee48bd90e5cf3f6;p=firefly-linux-kernel-4.4.55.git

diff --git a/fs/namei.c b/fs/namei.c
index 209ca7737cb2..0b0acba72a71 100644
--- a/fs/namei.c
+++ b/fs/namei.c
@@ -887,6 +887,7 @@ static inline int may_follow_link(struct nameidata *nd)
 {
 	const struct inode *inode;
 	const struct inode *parent;
+	kuid_t puid;
 
 	if (!sysctl_protected_symlinks)
 		return 0;
@@ -902,7 +903,8 @@ static inline int may_follow_link(struct nameidata *nd)
 		return 0;
 
 	/* Allowed if parent directory and link owner match. */
-	if (uid_eq(parent->i_uid, inode->i_uid))
+	puid = parent->i_uid;
+	if (uid_valid(puid) && uid_eq(puid, inode->i_uid))
 		return 0;
 
 	if (nd->flags & LOOKUP_RCU)