util/iov: Avoid dynamic stack allocation

Use autofree heap allocation instead of variable-length array on the
stack.

The codebase has very few VLAs, and if we can get rid of them all we
can make the compiler error on new additions.  This is a defensive
measure against security bugs where an on-stack dynamic allocation
isn't correctly size-checked (e.g.  CVE-2021-3527).

Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Message-ID: <20230824164706.2652277-1-peter.maydell@linaro.org>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
This commit is contained in:
Philippe Mathieu-Daudé 2023-08-24 17:47:06 +01:00 committed by Eric Blake
parent 06e0f098d6
commit 522a9b94e0

View File

@ -571,7 +571,7 @@ static int sortelem_cmp_src_index(const void *a, const void *b)
*/
void qemu_iovec_clone(QEMUIOVector *dest, const QEMUIOVector *src, void *buf)
{
IOVectorSortElem sortelems[src->niov];
g_autofree IOVectorSortElem *sortelems = g_new(IOVectorSortElem, src->niov);
void *last_end;
int i;