f_thor: check pointer before use in downlaod_tail()

Change-Id: Ic0be6b313eb293f607192b9fddf3b8f911ab91bd
Signed-off-by: Przemyslaw Marczak <p.marczak@samsung.com>

diff --git a/drivers/usb/gadget/f_thor.c b/drivers/usb/gadget/f_thor.c
index ef06a5a..fc7f220 100644 (file)
--- a/drivers/usb/gadget/f_thor.c
+++ b/drivers/usb/gadget/f_thor.c
@@ -215,12 +215,25 @@ static long long int download_head(unsigned long long total,
 
 static int download_tail(long long int left, int cnt)
 {
-       struct dfu_entity *dfu_entity = dfu_get_entity(alt_setting_num);
-       void *transfer_buffer = dfu_get_buf(dfu_entity);
+       struct dfu_entity *dfu_entity;
+       void *transfer_buffer;
        int ret;
 
        debug("%s: left: %llu cnt: %d\n", __func__, left, cnt);
 
+       dfu_entity = dfu_get_entity(alt_setting_num);
+       if (!dfu_entity) {
+               printf("Alt setting: %d entity not found!\n", alt_setting_num);
+               return -ENOENT;
+       }
+
+       transfer_buffer = dfu_get_buf(dfu_entity);
+       if (!transfer_buffer) {
+               printf("Alt setting: %d transfer buffer is NULL!\n",
+                      alt_setting_num);
+               return -ENXIO;
+       }
+
 #ifdef CONFIG_SIG
        /* check board signature when download u-boot-mmc.bin */
        ret = check_board_signature(f_name, (phys_addr_t)transfer_buffer,