9p/net: fix missing error check in p9_check_errors

BugLink: https://bugs.launchpad.net/bugs/1953387
commit 27eb4c3144f7a5ebef3c9a261d80cb3e1fa784dc upstream.

Link: https://lkml.kernel.org/r/99338965-d36c-886e-cd0e-1d8fff2b4746@gmail.com
Reported-by: syzbot+06472778c97ed94af66d@syzkaller.appspotmail.com
Cc: stable@vger.kernel.org
Signed-off-by: Dominique Martinet <asmadeus@codewreck.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Kamal Mostafa <kamal@canonical.com>
Signed-off-by: Kelsey Skunberg <kelsey.skunberg@canonical.com>

diff --git a/net/9p/client.c b/net/9p/client.c
index 1d48afc7033ca9aa00b650bd4a083b141c5f6ee8..b03fce66eb8de1719e2161cac98c211c3f67b515 100644 (file)
--- a/net/9p/client.c
+++ b/net/9p/client.c
@@ -538,6 +538,8 @@ static int p9_check_errors(struct p9_client *c, struct p9_req_t *req)
                kfree(ename);
        } else {
                err = p9pdu_readf(&req->rc, c->proto_version, "d", &ecode);
+               if (err)
+                       goto out_err;
                err = -ecode;
 
                p9_debug(P9_DEBUG_9P, "<<< RLERROR (%d)\n", -ecode);