cifs: fix sockaddr comparison in iface_cmp

iface_cmp used to simply do a memcmp of the two
provided struct sockaddrs. The comparison needs to do more
based on the address family. Similar logic was already
present in cifs_match_ipaddr. Doing something similar now.

Signed-off-by: Shyam Prasad N <sprasad@microsoft.com>
Reported-by: kernel test robot <lkp@intel.com>
Reported-by: Dan Carpenter <error27@gmail.com>
Signed-off-by: Steve French <stfrench@microsoft.com>

1 files changed, 50 insertions, 0 deletions

diff --git a/fs/smb/client/connect.c b/fs/smb/client/connect.c
index 1250d156619b..9d16626e7a66 100644
--- a/fs/smb/client/connect.c
+++ b/fs/smb/client/connect.c
@@ -1288,6 +1288,56 @@ next_pdu:
 	module_put_and_kthread_exit(0);
 }
 
+int
+cifs_ipaddr_cmp(struct sockaddr *srcaddr, struct sockaddr *rhs)
+{
+	struct sockaddr_in *saddr4 = (struct sockaddr_in *)srcaddr;
+	struct sockaddr_in *vaddr4 = (struct sockaddr_in *)rhs;
+	struct sockaddr_in6 *saddr6 = (struct sockaddr_in6 *)srcaddr;
+	struct sockaddr_in6 *vaddr6 = (struct sockaddr_in6 *)rhs;
+
+	switch (srcaddr->sa_family) {
+	case AF_UNSPEC:
+		switch (rhs->sa_family) {
+		case AF_UNSPEC:
+			return 0;
+		case AF_INET:
+		case AF_INET6:
+			return 1;
+		default:
+			return -1;
+		}
+	case AF_INET: {
+		switch (rhs->sa_family) {
+		case AF_UNSPEC:
+			return -1;
+		case AF_INET:
+			return memcmp(saddr4, vaddr4,
+				      sizeof(struct sockaddr_in));
+		case AF_INET6:
+			return 1;
+		default:
+			return -1;
+		}
+	}
+	case AF_INET6: {
+		switch (rhs->sa_family) {
+		case AF_UNSPEC:
+		case AF_INET:
+			return -1;
+		case AF_INET6:
+			return memcmp(saddr6,
+				      vaddr6,
+				      sizeof(struct sockaddr_in6));
+		default:
+			return -1;
+		}
+	}
+	default:
+		return -1; /* don't expect to be here */
+	}
+}
+
 /*
  * Returns true if srcaddr isn't specified and rhs isn't specified, or
  * if srcaddr is specified and matches the IP address of the rhs argument