SUNRPC: Make sure server name is reasonable before trying to print it

Check the length of the passed-in server name before trying to print it in
the log.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

1 files changed, 8 insertions, 2 deletions

diff --git a/net/sunrpc/clnt.c b/net/sunrpc/clnt.c
index c3d571abcded..0357819ffdb0 100644
--- a/net/sunrpc/clnt.c
+++ b/net/sunrpc/clnt.c
@@ -127,7 +127,14 @@ static struct rpc_clnt * rpc_new_client(struct rpc_xprt *xprt, char *servname, s
         struct rpc_clnt         *clnt = NULL;
         struct rpc_auth         *auth;
         int err;
-        int len;
+        size_t len;
+
+        /* sanity check the name before trying to print it */
+        err = -EINVAL;
+        len = strlen(servname);
+        if (len > RPC_MAXNETNAMELEN)
+                goto out_no_rpciod;
+        len++;
 
         dprintk("RPC:       creating %s client for %s (xprt %p)\n",
                         program->name, servname, xprt);
@@ -148,7 +155,6 @@ static struct rpc_clnt * rpc_new_client(struct rpc_xprt *xprt, char *servname, s
         clnt->cl_parent = clnt;
 
         clnt->cl_server = clnt->cl_inline_name;
-        len = strlen(servname) + 1;
         if (len > sizeof(clnt->cl_inline_name)) {
                 char *buf = kmalloc(len, GFP_KERNEL);
                 if (buf != 0)