net/9p: Fix the msize calculation.

commit c9ffb05ca5b5098d6ea468c909dd384d90da7d54 upstream.

msize represents the maximum PDU size that includes P9_IOHDRSZ.

Signed-off-by: Venkateswararao Jujjuri "<jvrao@linux.vnet.ibm.com>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

diff --git a/net/9p/client.c b/net/9p/client.c
index d2608ce..5532710 100644
--- a/net/9p/client.c
+++ b/net/9p/client.c
@@ -822,8 +822,8 @@
 	if (err)
 		goto destroy_fidpool;
 
-	if ((clnt->msize+P9_IOHDRSZ) > clnt->trans_mod->maxsize)
-		clnt->msize = clnt->trans_mod->maxsize-P9_IOHDRSZ;
+	if (clnt->msize > clnt->trans_mod->maxsize)
+		clnt->msize = clnt->trans_mod->maxsize;
 
 	err = p9_client_version(clnt);
 	if (err)