mtd: physmap_of: fix null pointer deference when kzalloc returns null

static analysis by smatch caught the following error:

drivers/mtd/maps/physmap_of.c:135 of_get_probes()
   error: potential null dereference 'res'.  (kzalloc returns null)

Check for failed kzalloc and return -ENOMEM in of_flash_probe if
this occurs.

Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>

diff --git a/drivers/mtd/maps/physmap_of.c b/drivers/mtd/maps/physmap_of.c
index 774b32fd29e673c10cf927cd159a5d50829d6e86..3e614e9119d58414c0adfdec475629eaf5bb44d4 100644 (file)
--- a/drivers/mtd/maps/physmap_of.c
+++ b/drivers/mtd/maps/physmap_of.c
@@ -130,6 +130,8 @@ static const char * const *of_get_probes(struct device_node *dp)
                        count++;
 
        res = kzalloc((count + 1)*sizeof(*res), GFP_KERNEL);
+       if (!res)
+               return NULL;
        count = 0;
        while (cplen > 0) {
                res[count] = cp;
@@ -311,6 +313,10 @@ static int of_flash_probe(struct platform_device *dev)
 
        ppdata.of_node = dp;
        part_probe_types = of_get_probes(dp);
+       if (!part_probe_types) {
+               err = -ENOMEM;
+               goto err_out;
+       }
        mtd_device_parse_register(info->cmtd, part_probe_types, &ppdata,
                        NULL, 0);
        of_free_probes(part_probe_types);