From: Simon Glass <sjg@chromium.org>
Date: Sat, 23 Oct 2021 23:26:02 +0000 (-0600)
Subject: disk: part_dos: Fix a NULL pointer error
X-Git-Url: http://git.dujemihanovic.xyz/?a=commitdiff_plain;h=b7c2cc49ffa50b8a0664460f3899536e07a78158;p=u-boot.git

disk: part_dos: Fix a NULL pointer error

When ext is NULL we cannot dereference it. Update the code flow to avoid
this, so that layout_mbr_partitions() can be used with partition tables
that do not include an extended partition.

Signed-off-by: Simon Glass <sjg@chromium.org>
---

diff --git a/disk/part_dos.c b/disk/part_dos.c
index 9e29aa6583..94fae7166d 100644
--- a/disk/part_dos.c
+++ b/disk/part_dos.c
@@ -459,10 +459,12 @@ int layout_mbr_partitions(struct disk_partition *p, int count,
 			ext = &p[i];
 	}
 
-	if (i >= 4 && !ext) {
-		printf("%s: extended partition is needed for more than 4 partitions\n",
-		        __func__);
-		return -1;
+	if (count < 4)
+		return 0;
+
+	if (!ext) {
+		log_err("extended partition is needed for more than 4 partitions\n");
+		return -EINVAL;
 	}
 
 	/* calculate extended volumes start and size if needed */