Fix a use-after-free in the child provider code

If the child provider context data gets cleaned up before all usage of
providers has finished then a use-after-free can occur. We change the
priority of this data so that it gets freed later.

Fixes #15284

Reviewed-by: Paul Dale <pauli@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/15286)

1 files changed, 1 insertions, 1 deletions

diff --git a/crypto/provider_child.c b/crypto/provider_child.c
index 2487d43fd7..14d0054624 100644
--- a/crypto/provider_child.c
+++ b/crypto/provider_child.c
@@ -47,7 +47,7 @@ static void child_prov_ossl_ctx_free(void *vgbl)
 }
 
 static const OSSL_LIB_CTX_METHOD child_prov_ossl_ctx_method = {
-    OSSL_LIB_CTX_METHOD_DEFAULT_PRIORITY,
+    OSSL_LIB_CTX_METHOD_LOW_PRIORITY,
     child_prov_ossl_ctx_new,
     child_prov_ossl_ctx_free,
 };