exofs: check for allocation failure in uri_store()

There is no memory allocation failure check in uri_store().
That can lead to NULL pointer dereference.

Found by Linux Driver Verification project (linuxtesting.org).

Signed-off-by: Alexey Khoroshilov <khoroshilov@ispras.ru>
Signed-off-by: Boaz Harrosh <bharrosh@panasas.com>

1 files changed, 6 insertions, 1 deletions

diff --git a/fs/exofs/sys.c b/fs/exofs/sys.c
index 5a7b691e748b..1b4f2f95fc37 100644
--- a/fs/exofs/sys.c
+++ b/fs/exofs/sys.c
@@ -80,8 +80,13 @@ static ssize_t uri_show(struct exofs_dev *edp, char *buf)
 
 static ssize_t uri_store(struct exofs_dev *edp, const char *buf, size_t len)
 {
+        uint8_t *new_uri;
+
         edp->urilen = strlen(buf) + 1;
-        edp->uri = krealloc(edp->uri, edp->urilen, GFP_KERNEL);
+        new_uri = krealloc(edp->uri, edp->urilen, GFP_KERNEL);
+        if (new_uri == NULL)
+                return -ENOMEM;
+        edp->uri = new_uri;
         strncpy(edp->uri, buf, edp->urilen);
         return edp->urilen;
 }