When both "crct10dif-pclmul" algorithm and "crct10dif-generic" algorithm
exist in crypto_alg_list, "crct10dif-pclmul" should be selected, since it
has higher priority than "crct10dif-generic". However, both algorithms
have the same cra_name "crct10dif". If we use "crct10dif" to find a
matched algorithm in crypto_alg_list, it's possible "crct10dif-generic" is
selected, because the code calls strcmp to decide if two string are exact
match, but doesn't check if two strings have the same length.
exact = !strcmp(q->cra_driver_name, name);
So ,if "crct10dif-generic" is in front of "crct10dif-pclmul" in
crypto_alg_list, it will be picked as the matched algorithm, even if it has
lower priority than "crct10dif-pclmul".
Signed-off-by: Ming Ma <[email protected]>
---
crypto/api.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/crypto/api.c b/crypto/api.c
index b16ce16..5b3d45a 100644
--- a/crypto/api.c
+++ b/crypto/api.c
@@ -76,7 +76,8 @@ static struct crypto_alg *__crypto_alg_lookup(const char *name, u32 type,
((struct crypto_larval *)q)->mask != mask)
continue;
- exact = !strcmp(q->cra_driver_name, name);
+ exact = (strlen(name) == strlen(q->cra_driver_name)) &&
+ !strcmp(q->cra_driver_name, name);
fuzzy = !strcmp(q->cra_name, name);
if (!exact && !(fuzzy && q->cra_priority > best))
continue;
--
2.4.11
On Tue, Mar 21, 2017 at 04:40:40PM -0500, Ming Ma wrote:
> When both "crct10dif-pclmul" algorithm and "crct10dif-generic" algorithm
> exist in crypto_alg_list, "crct10dif-pclmul" should be selected, since it
> has higher priority than "crct10dif-generic". However, both algorithms
> have the same cra_name "crct10dif". If we use "crct10dif" to find a
> matched algorithm in crypto_alg_list, it's possible "crct10dif-generic" is
> selected, because the code calls strcmp to decide if two string are exact
> match, but doesn't check if two strings have the same length.
>
> exact = !strcmp(q->cra_driver_name, name);
>
> So ,if "crct10dif-generic" is in front of "crct10dif-pclmul" in
> crypto_alg_list, it will be picked as the matched algorithm, even if it has
> lower priority than "crct10dif-pclmul".
> Signed-off-by: Ming Ma <[email protected]>
> ---
> crypto/api.c | 3 ++-
> 1 file changed, 2 insertions(+), 1 deletion(-)
>
> diff --git a/crypto/api.c b/crypto/api.c
> index b16ce16..5b3d45a 100644
> --- a/crypto/api.c
> +++ b/crypto/api.c
> @@ -76,7 +76,8 @@ static struct crypto_alg *__crypto_alg_lookup(const char *name, u32 type,
> ((struct crypto_larval *)q)->mask != mask)
> continue;
>
> - exact = !strcmp(q->cra_driver_name, name);
> + exact = (strlen(name) == strlen(q->cra_driver_name)) &&
> + !strcmp(q->cra_driver_name, name);
> fuzzy = !strcmp(q->cra_name, name);
> if (!exact && !(fuzzy && q->cra_priority > best))
> continue;
This is bogus. Please describe how you reproduced the problem.
The priority matching should work.
Cheers,
--
Email: Herbert Xu <[email protected]>
Home Page: http://gondor.apana.org.au/~herbert/
PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt
Please ignore this patch, we have seen some issues in older verison of linux kernel. But it doesn't seem to be an issue in the latest kernel.
thanks
-----Original Message-----
From: [email protected] [mailto:[email protected]] On Behalf Of Herbert Xu
Sent: Tuesday, March 21, 2017 8:01 PM
To: Ming Ma (mingma) <[email protected]>
Cc: [email protected]; [email protected]; [email protected]
Subject: Re: [PATCH 1/1] crypto: If two strings are exact match, they must have same length.
On Tue, Mar 21, 2017 at 04:40:40PM -0500, Ming Ma wrote:
> When both "crct10dif-pclmul" algorithm and "crct10dif-generic"
> algorithm exist in crypto_alg_list, "crct10dif-pclmul" should be
> selected, since it has higher priority than "crct10dif-generic".
> However, both algorithms have the same cra_name "crct10dif". If we use
> "crct10dif" to find a matched algorithm in crypto_alg_list, it's
> possible "crct10dif-generic" is selected, because the code calls
> strcmp to decide if two string are exact match, but doesn't check if two strings have the same length.
>
> exact = !strcmp(q->cra_driver_name, name);
>
> So ,if "crct10dif-generic" is in front of "crct10dif-pclmul" in
> crypto_alg_list, it will be picked as the matched algorithm, even if
> it has lower priority than "crct10dif-pclmul".
> Signed-off-by: Ming Ma <[email protected]>
> ---
> crypto/api.c | 3 ++-
> 1 file changed, 2 insertions(+), 1 deletion(-)
>
> diff --git a/crypto/api.c b/crypto/api.c index b16ce16..5b3d45a 100644
> --- a/crypto/api.c
> +++ b/crypto/api.c
> @@ -76,7 +76,8 @@ static struct crypto_alg *__crypto_alg_lookup(const char *name, u32 type,
> ((struct crypto_larval *)q)->mask != mask)
> continue;
>
> - exact = !strcmp(q->cra_driver_name, name);
> + exact = (strlen(name) == strlen(q->cra_driver_name)) &&
> + !strcmp(q->cra_driver_name, name);
> fuzzy = !strcmp(q->cra_name, name);
> if (!exact && !(fuzzy && q->cra_priority > best))
> continue;
This is bogus. Please describe how you reproduced the problem.
The priority matching should work.
Cheers,
--
Email: Herbert Xu <[email protected]> Home Page: http://gondor.apana.org.au/~herbert/
PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt