[PATCH 1/1] kwbimage: check return value of image_get_csk_index

[Heinrich Schuchardt]

image_get_csk_index() may return -1 in case of an error. Don't use this
value as index.

This resolves Coverity CID 338488
Memory - illegal accesses  (NEGATIVE_RETURNS)

Signed-off-by: Heinrich Schuchardt <xypron.glpk at gmx.de>
---
 tools/kwbimage.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/tools/kwbimage.c b/tools/kwbimage.c
index 2a10df773b..bf7fd135ac 100644
--- a/tools/kwbimage.c
+++ b/tools/kwbimage.c
@@ -1087,7 +1087,7 @@ int kwb_sign_csk_with_kak(struct image_tool_params *params,
 	int csk_idx = image_get_csk_index();
 	struct sig_v1 tmp_sig;

-	if (csk_idx >= 16) {
+	if (csk_idx < 0 || csk_idx > 15) {
 		fprintf(stderr, "Invalid CSK index %d\n", csk_idx);
 		return 1;
 	}
--
2.30.2