[PATCH master 2/3] common: machine_id: guard against digest algo being unavailable

[Ahmad Fatoum]

All callsites of digest_alloc(_by_algo) check for NULL pointer before
proceeding except for machine_id_set_globalvar(). Fix this to fail
more gracefully instead of the crash I ran into.

Signed-off-by: Ahmad Fatoum <a.fatoum at pengutronix.de>
---
 common/machine_id.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/common/machine_id.c b/common/machine_id.c
index a530fdeb1da8..189e74bd6796 100644
--- a/common/machine_id.c
+++ b/common/machine_id.c
@@ -30,14 +30,15 @@ static int machine_id_set_globalvar(void)
 	unsigned char machine_id[SHA1_DIGEST_SIZE];
 	char hex_machine_id[MACHINE_ID_LENGTH];
 	char *env_machine_id;
-	int ret;
+	int ret = -EOPNOTSUPP;
 
 	/* nothing to do if no hashable information provided */
 	if (!__machine_id_hashable)
 		return 0;
 
 	digest = digest_alloc_by_algo(HASH_ALGO_SHA1);
-	ret = digest_init(digest);
+	if (digest)
+		ret = digest_init(digest);
 	if (ret)
 		goto out;
 
-- 
2.30.2