net/llc: make opt unsigned in llc_ui_setsockopt()

The members of struct llc_sock are unsigned so if we pass a negative
value for "opt" it can cause a sign bug.  Also it can cause an integer
overflow when we multiply "opt * HZ".

CC: stable@kernel.org
Signed-off-by: Dan Carpenter <error27@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 2 insertions, 1 deletions

diff --git a/net/llc/af_llc.c b/net/llc/af_llc.c
index 023ba820236f..582612998211 100644
--- a/net/llc/af_llc.c
+++ b/net/llc/af_llc.c
@@ -1024,7 +1024,8 @@ static int llc_ui_setsockopt(struct socket *sock, int level, int optname,
 {
         struct sock *sk = sock->sk;
         struct llc_sock *llc = llc_sk(sk);
-        int rc = -EINVAL, opt;
+        unsigned int opt;
+        int rc = -EINVAL;
 
         lock_sock(sk);
         if (unlikely(level != SOL_LLC || optlen != sizeof(int)))