commit 1205afb3e10194fe22fa76385abb7e522144eb29
author Miss Islington (bot) <31488909+miss-islington@users.noreply.github.com> Fri May 01 16:06:23 2020 -0700
committer GitHub <noreply@github.com> Fri May 01 16:06:23 2020 -0700
tree 1f08b7636d20424caf0c02ad0b5a97da00af8625
parent e05828055e5165cc7268ea3bea33adc502e054a1

bpo-40412: Nullify inittab_copy during finalization (GH-19746)


Otherwise we leave a dangling pointer to free'd memory. If we
then initialize a new interpreter in the same process and call
PyImport_ExtendInittab, we will (likely) crash when calling
PyMem_RawRealloc(inittab_copy, ...) since the pointer address
is bogus.

Automerge-Triggered-By: @brettcannon
(cherry picked from commit 64224a4727321a8dd33e6f769edda401193ebef0)

Co-authored-by: Gregory Szorc <gregory.szorc@gmail.com>

Python/import.c

diff --git a/Python/import.c b/Python/import.c
index 495012d..b4074d1 100644
--- a/Python/import.c
+++ b/Python/import.c
@@ -300,6 +300,7 @@
 
     /* Free memory allocated by PyImport_ExtendInittab() */
     PyMem_RawFree(inittab_copy);
+    inittab_copy = NULL;
 
     PyMem_SetAllocator(PYMEM_DOMAIN_RAW, &old_alloc);
 }