diff mbox series

crypto: x86/curve25519 - fix cpu feature checking logic in mod_exit

Message ID 20210603055341.24473-1-liuhangbin@gmail.com
State New
Headers show
Series crypto: x86/curve25519 - fix cpu feature checking logic in mod_exit | expand

Commit Message

Hangbin Liu June 3, 2021, 5:53 a.m. UTC
In curve25519_mod_init() the curve25519_alg will be registered only when
(X86_FEATURE_BMI2 && X86_FEATURE_ADX). But in curve25519_mod_exit()
it still checks (X86_FEATURE_BMI2 || X86_FEATURE_ADX) when do crypto
unregister. This will trigger a BUG_ON in crypto_unregister_alg() as
alg->cra_refcnt is 0 if the cpu only supports one of X86_FEATURE_BMI2
and X86_FEATURE_ADX.

Fixes: 07b586fe0662 ("crypto: x86/curve25519 - replace with formally verified implementation")
Signed-off-by: Hangbin Liu <liuhangbin@gmail.com>
---
 arch/x86/crypto/curve25519-x86_64.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

Comments

Herbert Xu June 11, 2021, 7:23 a.m. UTC | #1
On Thu, Jun 03, 2021 at 01:53:40AM -0400, Hangbin Liu wrote:
> In curve25519_mod_init() the curve25519_alg will be registered only when
> (X86_FEATURE_BMI2 && X86_FEATURE_ADX). But in curve25519_mod_exit()
> it still checks (X86_FEATURE_BMI2 || X86_FEATURE_ADX) when do crypto
> unregister. This will trigger a BUG_ON in crypto_unregister_alg() as
> alg->cra_refcnt is 0 if the cpu only supports one of X86_FEATURE_BMI2
> and X86_FEATURE_ADX.
> 
> Fixes: 07b586fe0662 ("crypto: x86/curve25519 - replace with formally verified implementation")
> Signed-off-by: Hangbin Liu <liuhangbin@gmail.com>
> ---
>  arch/x86/crypto/curve25519-x86_64.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)

Patch applied.  Thanks.
diff mbox series

Patch

diff --git a/arch/x86/crypto/curve25519-x86_64.c b/arch/x86/crypto/curve25519-x86_64.c
index 6706b6cb1d0f..38caf61cd5b7 100644
--- a/arch/x86/crypto/curve25519-x86_64.c
+++ b/arch/x86/crypto/curve25519-x86_64.c
@@ -1500,7 +1500,7 @@  static int __init curve25519_mod_init(void)
 static void __exit curve25519_mod_exit(void)
 {
 	if (IS_REACHABLE(CONFIG_CRYPTO_KPP) &&
-	    (boot_cpu_has(X86_FEATURE_BMI2) || boot_cpu_has(X86_FEATURE_ADX)))
+	    static_branch_likely(&curve25519_use_bmi2_adx))
 		crypto_unregister_kpp(&curve25519_alg);
 }