Thread: pgsql: Avoid potential pfree on NULL on OpenSSL errors

Avoid potential pfree on NULL on OpenSSL errors

Guard against the pointer being NULL before pfreeing upon an error
returned from OpenSSL.  Also handle errors from X509_NAME_print_ex
which also can return -1 on memory allocation errors.

Backpatch down to v15 where the code was added.

Author: Sergey Shinderuk <s.shinderuk@postgrespro.ru>
Discussion: https://postgr.es/m/8db5374d-32e0-6abb-d402-40762511eff2@postgrespro.ru
Backpatch-through: v15

Branch
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REL_16_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/f720875a4670f94c6d8acd288a2a62c7cabb92dd

Modified Files
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src/backend/libpq/be-secure-openssl.c | 25 +++++++++++++++++--------
1 file changed, 17 insertions(+), 8 deletions(-)