From: Sjoerd Simons <sjoerd.simons@collabora.co.uk>
Date: Sun, 16 Feb 2020 21:36:24 +0000 (+0100)
Subject: um: vector: Avoid NULL ptr deference if transport is unset
X-Git-Tag: v5.7-rc1~62^2~1
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=237ce2e681d20e92fe17fc23a348b4f0d595e641;p=thirdparty%2Flinux.git

um: vector: Avoid NULL ptr deference if transport is unset

When the transport option of a vec isn't set strncmp ends up being
called on a NULL pointer. Better not do that.

Signed-off-by: Sjoerd Simons <sjoerd.simons@collabora.co.uk>
Acked-By: Anton Ivanov <anton.ivanov@cambridgegreys.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
---

diff --git a/arch/um/drivers/vector_kern.c b/arch/um/drivers/vector_kern.c
index 9693dfca76513..8e8aac1d30e13 100644
--- a/arch/um/drivers/vector_kern.c
+++ b/arch/um/drivers/vector_kern.c
@@ -197,6 +197,9 @@ static int get_transport_options(struct arglist *def)
 	long parsed;
 	int result = 0;
 
+	if (transport == NULL)
+		return -EINVAL;
+
 	if (vector != NULL) {
 		if (kstrtoul(vector, 10, &parsed) == 0) {
 			if (parsed == 0) {