[PATCH] mtd/redboot: avoid null pointer deref

[Jason A. Donenfeld]

By giving a bogus partition name, it's possible to trigger a null
pointer dereference.

Signed-off-by: Jason A. Donenfeld <Jason at zx2c4.com>
---
 drivers/mtd/redboot.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/drivers/mtd/redboot.c b/drivers/mtd/redboot.c
index 7623ac5fc586..53949ef80d36 100644
--- a/drivers/mtd/redboot.c
+++ b/drivers/mtd/redboot.c
@@ -212,6 +212,10 @@ static int parse_redboot_partitions(struct mtd_info *master,
 
 		nrparts++;
 	}
+	if (!fl) {
+		ret = -EINVAL;
+		goto out;
+	}
 #ifdef CONFIG_MTD_REDBOOT_PARTS_UNALLOCATED
 	if (fl->img->flash_base) {
 		nrparts++;
-- 
2.11.0