From 96a68f21c305d33f89e1e0bc9c45b6afb0de7654 Mon Sep 17 00:00:00 2001
From: Pauli <ppzgs1@gmail.com>
Date: Tue, 23 Mar 2021 10:33:15 +1000
Subject: [PATCH] x509: fix coverity 1461225: data race condition

Reviewed-by: Tomas Mraz <tomas@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/14651)
---
 crypto/x509/v3_purp.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/crypto/x509/v3_purp.c b/crypto/x509/v3_purp.c
index b98fc584ff..5b13fd7445 100644
--- a/crypto/x509/v3_purp.c
+++ b/crypto/x509/v3_purp.c
@@ -681,7 +681,10 @@ static int check_ca(const X509 *x)
 
 void X509_set_proxy_flag(X509 *x)
 {
-    x->ex_flags |= EXFLAG_PROXY;
+    if (CRYPTO_THREAD_write_lock(x->lock)) {
+        x->ex_flags |= EXFLAG_PROXY;
+        CRYPTO_THREAD_unlock(x->lock);
+    }
 }
 
 void X509_set_proxy_pathlen(X509 *x, long l)