[PATCH 03/11] hornet: fix off-by-one bug in max used maps check

[Blaise Boscaccy]

Sashiko correctly reported an off-by-one logic error checking against
the maximum number of used maps.  Removing the index constraint allows
us to simplify the check logic.

Signed-off-by: Blaise Boscaccy <bboscaccy at linux.microsoft.com>
---
 security/hornet/hornet_lsm.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/security/hornet/hornet_lsm.c b/security/hornet/hornet_lsm.c
index 35d9522d6bc72..eeb422db1092d 100644
--- a/security/hornet/hornet_lsm.c
+++ b/security/hornet/hornet_lsm.c
@@ -49,8 +49,7 @@ int hornet_next_map(void *context, size_t hdrlen,
 {
 	struct hornet_parse_context *ctx = (struct hornet_parse_context *)context;
 
-	if (++ctx->security->signed_hash_count >= MAX_USED_MAPS)
-		return -EINVAL;
+	ctx->security->signed_hash_count++;
 	return 0;
 }
 
@@ -63,6 +62,8 @@ int hornet_map_hash(void *context, size_t hdrlen,
 
 	if (vlen != SHA256_DIGEST_SIZE && vlen != 0)
 		return -EINVAL;
+	if (ctx->security->signed_hash_count >= MAX_USED_MAPS)
+		return -EINVAL;
 
 	memcpy(&ctx->security->signed_hashes[ctx->security->signed_hash_count * SHA256_DIGEST_SIZE],
 	       value, vlen);
-- 
2.53.0