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: linux-crypto-owner@xxxxxxxxxxxxxxx [mailto:linux-crypto-owner@xxxxxxxxxxxxxxx] On Behalf Of Herbert Xu Sent: Tuesday, March 21, 2017 8:01 PM To: Ming Ma (mingma) <mingma@xxxxxxxxxx> Cc: davem@xxxxxxxxxxxxx; linux-crypto@xxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx 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 <mingma@xxxxxxxxxx> > --- > 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 <herbert@xxxxxxxxxxxxxxxxxxx> Home Page: http://gondor.apana.org.au/~herbert/ PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt
