drivers/misc/ti-st/st_core.c: missing NULL check

Addresses https://bugzilla.kernel.org/show_bug.cgi?44431

Reported-by: <rucsoftsec@gmail.com>
Signed-off-by: Alan Cox <alan@linux.intel.com>
Cc: Pavan Savoy <pavan_savoy@ti.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/drivers/misc/ti-st/st_core.c b/drivers/misc/ti-st/st_core.c
index 2b62232..acfaeeb 100644
--- a/drivers/misc/ti-st/st_core.c
+++ b/drivers/misc/ti-st/st_core.c
@@ -349,6 +349,11 @@
 			st_gdata->rx_skb = alloc_skb(
 					st_gdata->list[type]->max_frame_size,
 					GFP_ATOMIC);
+			if (st_gdata->rx_skb == NULL) {
+				pr_err("out of memory: dropping\n");
+				goto done;
+			}
+
 			skb_reserve(st_gdata->rx_skb,
 					st_gdata->list[type]->reserve);
 			/* next 2 required for BT only */