Re: [PATCH v4 3/3] certs: don't try to update blacklist keys

When the same key is blacklisted repeatedly logging at pr_err() level is
excessive as no functionality is impaired.
When these duplicates are provided by buggy firmware there is nothing
the user can do to fix the situation.
Instead of spamming the bootlog with errors we use a warning that can
still be seen by OEMs when testing their firmware.

Link: https://lore.kernel.org/all/c8c65713-5cda-43ad-8018-20f2e32e4432@t-8ch.de/ (local)
Link: https://lore.kernel.org/all/20221104014704.3469-1-linux@weissschuh.net/ (local)
Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Tested-by: Paul Menzel <redacted>
---
 certs/blacklist.c | 21 ++++++++++++---------
 1 file changed, 12 insertions(+), 9 deletions(-)

diff --git a/certs/blacklist.c b/certs/blacklist.c
index 6e260c4b6a19..675dd7a8f07a 100644
--- a/certs/blacklist.c
+++ b/certs/blacklist.c

@@ -183,16 +183,19 @@ static int mark_raw_hash_blacklisted(const char *hash)
 {
 	key_ref_t key;
 
-	key = key_create_or_update(make_key_ref(blacklist_keyring, true),
-				   "blacklist",
-				   hash,
-				   NULL,
-				   0,
-				   BLACKLIST_KEY_PERM,
-				   KEY_ALLOC_NOT_IN_QUOTA |
-				   KEY_ALLOC_BUILT_IN);
+	key = key_create(make_key_ref(blacklist_keyring, true),
+			 "blacklist",
+			 hash,
+			 NULL,
+			 0,
+			 BLACKLIST_KEY_PERM,
+			 KEY_ALLOC_NOT_IN_QUOTA |
+			 KEY_ALLOC_BUILT_IN);
 	if (IS_ERR(key)) {
-		pr_err("Problem blacklisting hash %s: %pe\n", hash, key);
+		if (PTR_ERR(key) == -EEXIST)
+			pr_warn("Duplicate blacklisted hash %s\n", hash);
+		else
+			pr_err("Problem blacklisting hash %s: %pe\n", hash, key);
 		return PTR_ERR(key);
 	}
 	return 0;

-- 
2.39.0