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>
diff --git a/net/9p/client.c b/net/9p/client.c
index 7bbd2d5..5bf5f22 100644
--- a/net/9p/client.c
+++ b/net/9p/client.c
@@ -411,14 +411,9 @@
if (c->dotu)
err = -ecode;
- if (!err) {
+ if (!err || !IS_ERR_VALUE(err))
err = p9_errstr2errno(ename, strlen(ename));
- /* string match failed */
- if (!err)
- err = -ESERVERFAULT;
- }
-
P9_DPRINTK(P9_DEBUG_9P, "<<< RERROR (%d) %s\n", -ecode, ename);
kfree(ename);
diff --git a/net/9p/error.c b/net/9p/error.c
index fdebe43..5251851 100644
--- a/net/9p/error.c
+++ b/net/9p/error.c
@@ -239,7 +239,7 @@
errstr[len] = 0;
printk(KERN_ERR "%s: server reported unknown error %s\n",
__func__, errstr);
- errno = 1;
+ errno = ESERVERFAULT;
}
return -errno;