AES-NI CPUID check: Avoid potential thread safety (non-?)issue

Mbed-TLS/mbedtls#9840
openwall · Dec 11, 2024 · 2d70dc9 · 2d70dc9
1 parent 0ab4262
commit 2d70dc9
Showing 1 changed file with 2 additions and 0 deletions.
diff --git a/src/mbedtls/aesni.c b/src/mbedtls/aesni.c
@@ -67,9 +67,11 @@ int mbedtls_aesni_has_support(unsigned int what)
              :
              : "eax", "ebx", "edx");
 #endif /* MBEDTLS_AESNI_HAVE_CODE */
+        asm ("" ::: "memory");
         done = 1;
     }
 
+    asm ("" ::: "memory");
     return (c & what) != 0;
 }
 #endif /* !MBEDTLS_AES_USE_HARDWARE_ONLY */