[PATCH] dma-buf: check the return value of kstrdup()

[xkernel.wang at foxmail.com]

From: Xiaoke Wang <xkernel.wang at foxmail.com>

kstrdup() is a memory allocation function which can return NULL when
some internaly memory errors happen. It is better to check the return
value of it to prevent further wrong memory access.

Signed-off-by: Xiaoke Wang <xkernel.wang at foxmail.com>
---
 drivers/dma-buf/selftest.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/dma-buf/selftest.c b/drivers/dma-buf/selftest.c
index c60b694..2c29e2a 100644
--- a/drivers/dma-buf/selftest.c
+++ b/drivers/dma-buf/selftest.c
@@ -50,6 +50,9 @@ static bool apply_subtest_filter(const char *caller, const char *name)
 	bool result = true;
 
 	filter = kstrdup(__st_filter, GFP_KERNEL);
+	if (!filter)
+		return false;
+
 	for (sep = filter; (tok = strsep(&sep, ","));) {
 		bool allow = true;
 		char *sl;
--