vfio: Clear the caps->buf to NULL after free

[ Upstream commit 6641085e8d ]

On buffer resize failure, vfio_info_cap_add() will free the buffer,
report zero for the size, and return -ENOMEM.  As additional
hardening, also clear the buffer pointer to prevent any chance of a
double free.

Signed-off-by: Schspa Shi <schspa@gmail.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Link: https://lore.kernel.org/r/20220629022948.55608-1-schspa@gmail.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
This commit is contained in:
Schspa Shi 2022-06-29 10:29:48 +08:00 committed by Greg Kroah-Hartman
parent a1d8021d21
commit c983edb062

View File

@ -1850,6 +1850,7 @@ struct vfio_info_cap_header *vfio_info_cap_add(struct vfio_info_cap *caps,
buf = krealloc(caps->buf, caps->size + size, GFP_KERNEL);
if (!buf) {
kfree(caps->buf);
caps->buf = NULL;
caps->size = 0;
return ERR_PTR(-ENOMEM);
}