mirrors/cpython
1
0
Fork 0
mirror of https://github.com/python/cpython.git synced 2025-08-04 17:08:35 +00:00
Code Issues Projects Releases Packages Wiki Activity Actions 13

gh-104432: Use memcpy() to avoid misaligned loads (#104433)

Browse source 
Fix potential unaligned memory access on C APIs involving returned sequences
of `char *` pointers within the :mod:`grp` and :mod:`socket` modules. These
were revealed using a ``-fsaniziter=alignment`` build on ARM macOS.
This commit is contained in:
Christopher Chavez 2023-07-27 14:20:25 -05:00 • committed by GitHub
parent 983305268e
commit f01e4cedba
No known key found for this signature in database
GPG key ID: 4AEE18F83AFDEB23
3 changed files with 29 additions and 7 deletions
Download patch file Download diff file Expand all files Collapse all files

10
Modules/grpmodule.c
View file

@ -65,8 +65,14 @@ mkgrent(PyObject *module, struct group *p)
Py_DECREF(v);
return NULL;
}
for (member = p->gr_mem; *member != NULL; member++) {
PyObject *x = PyUnicode_DecodeFSDefault(*member);
for (member = p->gr_mem; ; member++) {
char *group_member;
// member can be misaligned
memcpy(&group_member, member, sizeof(group_member));
if (group_member == NULL) {
break;
}
PyObject *x = PyUnicode_DecodeFSDefault(group_member);
if (x == NULL || PyList_Append(w, x) != 0) {
Py_XDECREF(x);
Py_DECREF(w);