commit 106c1df736d38f5b411a8571b97275d0ecf1d0a9
author Miss Islington (bot) <31488909+miss-islington@users.noreply.github.com> Fri Sep 04 15:56:04 2020 -0700
committer GitHub <noreply@github.com> Fri Sep 04 15:56:04 2020 -0700
tree f25110dcb686f445ab6a4a9f37683650aada5df1
parent 8ed1c177c99f6d27bf9f68ce0728f215205eca69

closes bpo-41533: Fix a potential memory leak when allocating a stack (GH-21847)


Free the stack allocated in va_build_stack if do_mkstack fails
and the stack is not a small_stack
(cherry picked from commit 75c80b0bda89debf312f075716b8c467d411f90e)

Co-authored-by: Tony Solomonik <tony.solomonik@gmail.com>

Python/modsupport.c

diff --git a/Python/modsupport.c b/Python/modsupport.c
index 845bdcb..13482c6 100644
--- a/Python/modsupport.c
+++ b/Python/modsupport.c
@@ -619,6 +619,9 @@
     va_end(lva);
 
     if (res < 0) {
+        if (stack != small_stack) {
+            PyMem_Free(stack);
+        }
         return NULL;
     }