net/9p: insulate the client against an invalid error code sent by a 9p server

A looney tunes server sending an invalid error code (which is !IS_ERR_VALUE)
can result in a client oops. So fix it by adding a check and converting unknown
or invalid error codes to -ESERVERFAULT.

Signed-off-by: Abhishek Kulkarni <adkulkar@umail.iu.edu>
Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>

1 files changed, 1 insertions, 1 deletions

diff --git a/net/9p/error.c b/net/9p/error.c
index fdebe4314062..52518512a93e 100644
--- a/net/9p/error.c
+++ b/net/9p/error.c
@@ -239,7 +239,7 @@ int p9_errstr2errno(char *errstr, int len)
                 errstr[len] = 0;
                 printk(KERN_ERR "%s: server reported unknown error %s\n",
                         __func__, errstr);
-                errno = 1;
+                errno = ESERVERFAULT;
         }
 
         return -errno;