[openssl-dev] [openssl.org #4518] OpenSSL-1.1.0-pre5 RSA_set0_key and related RSA_get0_*, RSA_set0_*, DSA_set0_* and DSA_get0_* problems

[Blumenthal, Uri - 0553 - MITLL]

On 4/26/16, 11:43 , "openssl-dev on behalf of Tomas Mraz"
<openssl-dev-bounces at openssl.org on behalf of tmraz at redhat.com> wrote:

>On Út, 2016-04-26 at 10:16 -0500, Douglas E Engert wrote:
>> Let me update my response.
>> If I am reading GH#995 correctly it still has an issue if a user
>> does:
>> 
>> RSA_get0_key(rsa, n, e, NULL); /* note this is a GET0 */
>> /* other stuff done, such as calculating d */
>> RSA_set0_key(rsa, n, e, d);
>> 
>> rsa is left with n and e pointing to unallocated storage.
>
>This is programmer error in your code because the RSA_get0_key is
>documented to just return internal data and must not be freed. Thus
>you're not allowed to pass the returned values to RSA_set0_key().

May I suggest that this (obvious to you) text be added to the manual page
for both _get0_key() and _set0_key()? [Yes it would be redundant, but IMHO
better than allowing a harried programmer making a silly mistake “because
he should’ve known better".]
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