From: Michael Paquier <michael@paquier.xyz>
Date: Sat, 14 Dec 2019 09:17:31 +0000 (+0900)
Subject: Fix memory leak when initializing DH parameters in backend
X-Git-Tag: REL_13_BETA1~1033
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=e0e569e1d192c3fed942257302f24b550cf982f4;p=thirdparty%2Fpostgresql.git

Fix memory leak when initializing DH parameters in backend

When loading DH parameters used for the generation of ephemeral DH keys
in the backend, the code has never bothered releasing the memory used
for the DH information loaded from a file or from libpq's default.  This
commit makes sure that the information is properly free()'d.

Note that as SSL parameters can be reloaded, this can cause an accumulation
of memory leaked.  As the leak is minor, no backpatch is done.

Reported-by: Dmitry Uspenskiy
Discussion: https://postgr.es/m/16160-18367e56e9a28264@postgresql.org
---

diff --git a/src/backend/libpq/be-secure-openssl.c b/src/backend/libpq/be-secure-openssl.c
index 629919cc6e1..5f0430ded75 100644
--- a/src/backend/libpq/be-secure-openssl.c
+++ b/src/backend/libpq/be-secure-openssl.c
@@ -1015,8 +1015,11 @@ initialize_dh(SSL_CTX *context, bool isServerStart)
 				(errcode(ERRCODE_CONFIG_FILE_ERROR),
 				 (errmsg("DH: could not set DH parameters: %s",
 						 SSLerrmessage(ERR_get_error())))));
+		DH_free(dh);
 		return false;
 	}
+
+	DH_free(dh);
 	return true;
 }