From: Karel Zak <kzak@redhat.com>
Date: Wed, 22 May 2019 15:42:48 +0000 (+0200)
Subject: libfdisk: (sgi) improve checksum calculation [-Waddress-of-packed-member]
X-Git-Tag: v2.34-rc2~38
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=1a56f15b0fe047dfd85fa1a7aaddcc8504e403a6;p=thirdparty%2Futil-linux.git

libfdisk: (sgi) improve checksum calculation [-Waddress-of-packed-member]

Let's keep compilers and static analyzers happy. The idea is to use
memcpy() to copy from buffer to variable and use all label as unsigned
char rather than vectorize by uint32_t.

Signed-off-by: Karel Zak <kzak@redhat.com>
---

diff --git a/include/pt-sgi.h b/include/pt-sgi.h
index 547b37a872..5d6b68f134 100644
--- a/include/pt-sgi.h
+++ b/include/pt-sgi.h
@@ -93,15 +93,20 @@ struct sgi_disklabel {
 
 static inline uint32_t sgi_pt_checksum(struct sgi_disklabel *label)
 {
-	int i;
-	uint32_t *ptr = (uint32_t *) label;
+	int count;
 	uint32_t sum = 0;
+	unsigned char *ptr = (unsigned char *) label;
 
-	i = sizeof(*label) / sizeof(*ptr);
+	count = sizeof(*label) / sizeof(uint32_t);
+	ptr += sizeof(uint32_t) * (count - 1);
 
-	while (i) {
-		i--;
-		sum -= be32_to_cpu(ptr[i]);
+	while (count--) {
+		uint32_t val;
+
+		memcpy(&val, ptr, sizeof(uint32_t));
+		sum -= be32_to_cpu(val);
+
+		ptr -= sizeof(uint32_t);
 	}
 
 	return sum;