bpo-37702: Fix SSL's certificate-store leak on Windows (GH-15632)

zooba · web-flow · commit 5d695b6b7bcc · 2019-09-09T06:48:22.000-07:00
ssl_collect_certificates function in _ssl.c has a memory leak.
Calling CertOpenStore() and CertAddStoreToCollection(), a store's refcnt gets incremented by 2.
But CertCloseStore() is called only once and the refcnt leaves 1.
diff --git a/Misc/NEWS.d/next/Windows/2019-07-29-16-49-31.bpo-37702.Lj2f5e.rst b/Misc/NEWS.d/next/Windows/2019-07-29-16-49-31.bpo-37702.Lj2f5e.rst
@@ -0,0 +1,2 @@
+Fix memory leak on Windows in creating an SSLContext object or
+running urllib.request.urlopen('https://...').
diff --git a/Modules/_ssl.c b/Modules/_ssl.c
@@ -5581,6 +5581,7 @@ ssl_collect_certificates(const char *store_name)
             if (result) {
                 ++storesAdded;
             }
+            CertCloseStore(hSystemStore, 0);  /* flag must be 0 */
         }
     }
     if (storesAdded == 0) {

Original file line number	Diff line number	Diff line change
`@@ -0,0 +1,2 @@`
	`1`	`+Fix memory leak on Windows in creating an SSLContext object or`
	`2`	`+running urllib.request.urlopen('https://...').`
Original file line number	Diff line number	Diff line change
`@@ -5581,6 +5581,7 @@ ssl_collect_certificates(const char *store_name)`
`5581`	`5581`	`if (result) {`
`5582`	`5582`	`++storesAdded;`
`5583`	`5583`	`}`
	`5584`	`+ CertCloseStore(hSystemStore, 0); /* flag must be 0 */`
`5584`	`5585`	`}`
`5585`	`5586`	`}`
`5586`	`5587`	`if (storesAdded == 0) {`