[PATCH 3/7] crypto: testmgr: fix warning

[PATCH 3/7] crypto: testmgr: fix warning

[Felipe Contreras]

crypto/testmgr.c: In function ‘test_cprng’:
crypto/testmgr.c:1204: warning: ‘err’ may be used uninitialized in this function

Signed-off-by: Felipe Contreras <felipe.contreras@gmail.com>
---
 crypto/testmgr.c |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)

diff --git a/crypto/testmgr.c b/crypto/testmgr.c
index 6d5b746..1f2357b 100644
--- a/crypto/testmgr.c
+++ b/crypto/testmgr.c
@@ -1201,7 +1201,7 @@ static int test_cprng(struct crypto_rng *tfm, struct cprng_testvec *template,
 		      unsigned int tcount)
 {
 	const char *algo = crypto_tfm_alg_driver_name(crypto_rng_tfm(tfm));
-	int err, i, j, seedsize;
+	int err = 0, i, j, seedsize;
 	u8 *seed;
 	char result[32];
 
-- 
1.6.5.1

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Re: [PATCH 3/7] crypto: testmgr: fix warning

[Jiri Kosina]

On Mon, 19 Oct 2009, Felipe Contreras wrote:

> crypto/testmgr.c: In function ?test_cprng?:
> crypto/testmgr.c:1204: warning: ?err? may be used uninitialized in this function
> 
> Signed-off-by: Felipe Contreras <felipe.contreras@gmail.com>
> ---
>  crypto/testmgr.c |    2 +-
>  1 files changed, 1 insertions(+), 1 deletions(-)
> 
> diff --git a/crypto/testmgr.c b/crypto/testmgr.c
> index 6d5b746..1f2357b 100644
> --- a/crypto/testmgr.c
> +++ b/crypto/testmgr.c
> @@ -1201,7 +1201,7 @@ static int test_cprng(struct crypto_rng *tfm, struct cprng_testvec *template,
>  		      unsigned int tcount)
>  {
>  	const char *algo = crypto_tfm_alg_driver_name(crypto_rng_tfm(tfm));
> -	int err, i, j, seedsize;
> +	int err = 0, i, j, seedsize;
>  	u8 *seed;
>  	char result[32];

As it is not obvious to me immediately why/whether tcount couldn't be zero 
(which would cause uninitialized use of 'err'), I am not merging this 
through trivial tree. Herbert?

-- 
Jiri Kosina
SUSE Labs, Novell Inc.

Re: [PATCH 3/7] crypto: testmgr: fix warning

[Jarod Wilson]

On 10/19/09 9:52 AM, Jiri Kosina wrote:
> On Mon, 19 Oct 2009, Felipe Contreras wrote:
>
>> crypto/testmgr.c: In function ?test_cprng?:
>> crypto/testmgr.c:1204: warning: ?err? may be used uninitialized in this function
>>
>> Signed-off-by: Felipe Contreras<felipe.contreras@gmail.com>
>> ---
>>   crypto/testmgr.c |    2 +-
>>   1 files changed, 1 insertions(+), 1 deletions(-)
>>
>> diff --git a/crypto/testmgr.c b/crypto/testmgr.c
>> index 6d5b746..1f2357b 100644
>> --- a/crypto/testmgr.c
>> +++ b/crypto/testmgr.c
>> @@ -1201,7 +1201,7 @@ static int test_cprng(struct crypto_rng *tfm, struct cprng_testvec *template,
>>   		      unsigned int tcount)
>>   {
>>   	const char *algo = crypto_tfm_alg_driver_name(crypto_rng_tfm(tfm));
>> -	int err, i, j, seedsize;
>> +	int err = 0, i, j, seedsize;
>>   	u8 *seed;
>>   	char result[32];
>
> As it is not obvious to me immediately why/whether tcount couldn't be zero
> (which would cause uninitialized use of 'err'), I am not merging this
> through trivial tree. Herbert?

I believe I'm the guilty party who wrote the code in question. 
Initializing err to 0 isn't correct. tcount should always be at least 1, 
if its 0, test_cprng has been called with invalid parameters. I believe 
err would best be initialized to -EINVAL, lest the caller think they 
were successful.

-- 
Jarod Wilson
jarod@redhat.com

Re: [PATCH 3/7] crypto: testmgr: fix warning

[Jarod Wilson]

On 10/19/09 9:58 AM, Jarod Wilson wrote:
> On 10/19/09 9:52 AM, Jiri Kosina wrote:
>> On Mon, 19 Oct 2009, Felipe Contreras wrote:
>>
>>> crypto/testmgr.c: In function ?test_cprng?:
>>> crypto/testmgr.c:1204: warning: ?err? may be used uninitialized in
>>> this function
>>>
>>> Signed-off-by: Felipe Contreras<felipe.contreras@gmail.com>
>>> ---
>>> crypto/testmgr.c | 2 +-
>>> 1 files changed, 1 insertions(+), 1 deletions(-)
>>>
>>> diff --git a/crypto/testmgr.c b/crypto/testmgr.c
>>> index 6d5b746..1f2357b 100644
>>> --- a/crypto/testmgr.c
>>> +++ b/crypto/testmgr.c
>>> @@ -1201,7 +1201,7 @@ static int test_cprng(struct crypto_rng *tfm,
>>> struct cprng_testvec *template,
>>> unsigned int tcount)
>>> {
>>> const char *algo = crypto_tfm_alg_driver_name(crypto_rng_tfm(tfm));
>>> - int err, i, j, seedsize;
>>> + int err = 0, i, j, seedsize;
>>> u8 *seed;
>>> char result[32];
>>
>> As it is not obvious to me immediately why/whether tcount couldn't be
>> zero
>> (which would cause uninitialized use of 'err'), I am not merging this
>> through trivial tree. Herbert?
>
> I believe I'm the guilty party who wrote the code in question.
> Initializing err to 0 isn't correct. tcount should always be at least 1,
> if its 0, test_cprng has been called with invalid parameters. I believe
> err would best be initialized to -EINVAL, lest the caller think they
> were successful.

...and I need to re-read said code more carefully. tcount is 
desc->suite.cprng.count, which is ANSI_CPRNG_AES_TEST_VECTORS, which is 
#define'd to 6, and is the count of how many cprng test vectors there 
are. If someone changes that to 0, then I guess a retval of 0 would 
actually be correct, since no tests failed...

So yeah, I rescind my claim that initializing err to 0 is incorrect, I 
think that's just fine.

-- 
Jarod Wilson
jarod@redhat.com

Re: [PATCH 3/7] crypto: testmgr: fix warning

[Felipe Contreras]

On Mon, Oct 19, 2009 at 4:03 PM, Jarod Wilson <jarod@redhat.com> wrote:
> So yeah, I rescind my claim that initializing err to 0 is incorrect, I think
> that's just fine.

So is this acked? Who will merge it?

-- 
Felipe Contreras

Re: [PATCH 3/7] crypto: testmgr: fix warning

[Herbert Xu]

On Thu, Nov 12, 2009 at 02:32:10AM +0200, Felipe Contreras wrote:
> On Mon, Oct 19, 2009 at 4:03 PM, Jarod Wilson <jarod@redhat.com> wrote:
> > So yeah, I rescind my claim that initializing err to 0 is incorrect, I think
> > that's just fine.
> 
> So is this acked? Who will merge it?

It's already in cryptodev-2.6:

commit fa4ef8a6af4745bbf3a25789bc7d4f14a3a6d803
Author: Felipe Contreras <felipe.contreras@gmail.com>
Date:   Tue Oct 27 19:04:42 2009 +0800

    crypto: testmgr - Fix warning

    crypto/testmgr.c: In function ‘test_cprng’:
    crypto/testmgr.c:1204: warning: ‘err’ may be used uninitialized in this function

    Signed-off-by: Felipe Contreras <felipe.contreras@gmail.com>

Cheers,
-- 
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Email: Herbert Xu ~{PmV>HI~} <herbert@gondor.apana.org.au>
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