[Python-checkins] bpo-42246: Fix memory leak in compiler (GH-23256)

Fri Nov 13 07:54:22 EST 2020

https://github.com/python/cpython/commit/fd009e606a48e803e7187983bf9a5682e938fddb
commit: fd009e606a48e803e7187983bf9a5682e938fddb
branch: master
author: Mark Shannon <mark at hotpy.org>
committer: markshannon <mark at hotpy.org>
date: 2020年11月13日T12:53:53Z
summary:
bpo-42246: Fix memory leak in compiler (GH-23256)
* Fix potential memory leak in assembler init.
* Fix reference leak when encountering error during compilation of function body.
files:
M Python/compile.c

diff --git a/Python/compile.c b/Python/compile.c
index 5a0292646b5c6..c2fcf096fbad4 100644
--- a/Python/compile.c
+++ b/Python/compile.c
@@ -2276,7 +2276,7 @@ compiler_function(struct compiler *c, stmt_ty s, int is_async)
 c->u->u_posonlyargcount = asdl_seq_LEN(args->posonlyargs);
 c->u->u_kwonlyargcount = asdl_seq_LEN(args->kwonlyargs);
 for (i = docstring ? 1 : 0; i < asdl_seq_LEN(body); i++) {
- VISIT(c, stmt, (stmt_ty)asdl_seq_GET(body, i));
+ VISIT_IN_SCOPE(c, stmt, (stmt_ty)asdl_seq_GET(body, i));
 }
 co = assemble(c, 1);
 qualname = c->u->u_qualname;
@@ -5533,18 +5533,24 @@ assemble_init(struct assembler *a, int nblocks, int firstlineno)
 {
 memset(a, 0, sizeof(struct assembler));
 a->a_prevlineno = a->a_lineno = firstlineno;
+ a->a_lnotab = NULL;
 a->a_bytecode = PyBytes_FromStringAndSize(NULL, DEFAULT_CODE_SIZE);
- if (!a->a_bytecode)
- return 0;
+ if (a->a_bytecode == NULL) {
+ goto error;
+ }
 a->a_lnotab = PyBytes_FromStringAndSize(NULL, DEFAULT_LNOTAB_SIZE);
- if (!a->a_lnotab)
- return 0;
+ if (a->a_lnotab == NULL) {
+ goto error;
+ }
 if ((size_t)nblocks > SIZE_MAX / sizeof(basicblock *)) {
 PyErr_NoMemory();
- return 0;
+ goto error;
 }
-
 return 1;
+error:
+ Py_XDECREF(a->a_bytecode);
+ Py_XDECREF(a->a_lnotab);
+ return 0;
 }
 
 static void
