[Cluster-devel] [PATCH 13/13] restoremeta: Skip the right number of bytes for the superblock

[Andrew Price <anprice@redhat.com>]

Fix a bug where the second saved block was reached by skipping over the
size of a gfs2 superblock, which is not always the correct offset.
Instead, skip over the length specified by the saved superblock's
descriptor.

Signed-off-by: Andrew Price <anprice@redhat.com>
---
 gfs2/edit/savemeta.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/gfs2/edit/savemeta.c b/gfs2/edit/savemeta.c
index e20b405d..63cb91af 100644
--- a/gfs2/edit/savemeta.c
+++ b/gfs2/edit/savemeta.c
@@ -1198,6 +1198,7 @@ static void complain(const char *complaint)
 static int restore_init(const char *path, struct metafd *mfd, struct savemeta_header *smh, int printonly)
 {
 	struct gfs2_meta_header *sbmh;
+	uint16_t sb_siglen;
 	char *end;
 	char *bp;
 	int ret;
@@ -1229,6 +1230,7 @@ static int restore_init(const char *path, struct metafd *mfd, struct savemeta_he
 	/* Scan for the position of the superblock. Required to support old formats(?). */
 	end = &restore_buf[256 + sizeof(struct saved_metablock) + sizeof(*sbmh)];
 	while (bp <= end) {
+		sb_siglen = be16_to_cpu(((struct saved_metablock *)bp)->siglen);
 		sbmh = (struct gfs2_meta_header *)(bp + sizeof(struct saved_metablock));
 		if (sbmh->mh_magic == cpu_to_be32(GFS2_MAGIC) &&
 		    sbmh->mh_type == cpu_to_be32(GFS2_METATYPE_SB))
@@ -1243,7 +1245,7 @@ static int restore_init(const char *path, struct metafd *mfd, struct savemeta_he
 	if (ret != 0)
 		return ret;
 
-	bp += sizeof(struct saved_metablock) + sizeof(sbd.sd_sb);
+	bp += sizeof(struct saved_metablock) + sb_siglen;
 	restore_off = bp - restore_buf;
 	restore_left -= restore_off;
 	return 0;
-- 
2.24.1