From: Schspa Shi <schspa@xxxxxxxxx> [ Upstream commit 6641085e8d7b3f061911517f79a2a15a0a21b97b ] 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@xxxxxxxxx> Reviewed-by: Cornelia Huck <cohuck@xxxxxxxxxx> Link: https://lore.kernel.org/r/20220629022948.55608-1-schspa@xxxxxxxxx Signed-off-by: Alex Williamson <alex.williamson@xxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- drivers/vfio/vfio.c | 1 + 1 file changed, 1 insertion(+) diff --git a/drivers/vfio/vfio.c b/drivers/vfio/vfio.c index 7a386fb30bf1..0d146b45e0b4 100644 --- a/drivers/vfio/vfio.c +++ b/drivers/vfio/vfio.c @@ -1808,6 +1808,7 @@ 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); } -- 2.35.1
