From b81e286ba154a4e0f01a94d99179a97f4ba3e396 Mon Sep 17 00:00:00 2001
From: Herbert Xu <herbert@gondor.apana.org.au>
Date: Sun, 6 Oct 2024 09:18:37 +0800
Subject: [PATCH] crypto: api - Fix liveliness check in crypto_alg_tested

As algorithm testing is carried out without holding the main crypto
lock, it is always possible for the algorithm to go away during the
test.

So before crypto_alg_tested updates the status of the tested alg,
it checks whether it's still on the list of all algorithms.  This
is inaccurate because it may be off the main list but still on the
list of algorithms to be removed.

Updating the algorithm status is safe per se as the larval still
holds a reference to it.  However, killing spawns of other algorithms
that are of lower priority is clearly a deficiency as it adds
unnecessary churn.

Fix the test by checking whether the algorithm is dead.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
---
 crypto/algapi.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/crypto/algapi.c b/crypto/algapi.c
index 74e2261c184ca..004d27e41315f 100644
--- a/crypto/algapi.c
+++ b/crypto/algapi.c
@@ -373,7 +373,7 @@ found:
 	q->cra_flags |= CRYPTO_ALG_DEAD;
 	alg = test->adult;
 
-	if (list_empty(&alg->cra_list))
+	if (crypto_is_dead(alg))
 		goto complete;
 
 	if (err == -ECANCELED)
-- 
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