net/9p: Fix crash due to bad mount parameters.

It is not safe to use match_int without checking the token type returned
by match_token (especially when the token type returned is Opt_err and
args is empty). Fix it.

Signed-off-by: Abhishek Kulkarni <adkulkar@umail.iu.edu>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/net/9p/trans_fd.c b/net/9p/trans_fd.c
index a2a1814..8c2588e 100644 (file)
--- a/net/9p/trans_fd.c
+++ b/net/9p/trans_fd.c
@@ -735,12 +735,14 @@ static int parse_opts(char *params, struct p9_fd_opts *opts)
                if (!*p)
                        continue;
                token = match_token(p, tokens, args);
-               r = match_int(&args[0], &option);
-               if (r < 0) {
-                       P9_DPRINTK(P9_DEBUG_ERROR,
-                        "integer field, but no integer?\n");
-                       ret = r;
-                       continue;
+               if (token != Opt_err) {
+                       r = match_int(&args[0], &option);
+                       if (r < 0) {
+                               P9_DPRINTK(P9_DEBUG_ERROR,
+                               "integer field, but no integer?\n");
+                               ret = r;
+                               continue;
+                       }
                }
                switch (token) {
                case Opt_port: