net/smc: add error handling for get_user()

For security reasons the return code of get_user() should always be
checked.

Fixes: 01d2f7e2cdd31 ("net/smc: sockopts TCP_NODELAY and TCP_CORK")
Reported-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Ursula Braun <ubraun@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 2 insertions, 1 deletions

diff --git a/net/smc/af_smc.c b/net/smc/af_smc.c
index c12a7fc18f56..6e5479067db0 100644
--- a/net/smc/af_smc.c
+++ b/net/smc/af_smc.c
@@ -1456,7 +1456,8 @@ static int smc_setsockopt(struct socket *sock, int level, int optname,
 
         if (optlen < sizeof(int))
                 return -EINVAL;
-        get_user(val, (int __user *)optval);
+        if (get_user(val, (int __user *)optval))
+                return -EFAULT;
 
         lock_sock(sk);
         switch (optname) {