From: Schspa Shi schspa@gmail.com
[ 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@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 --- drivers/vfio/vfio.c | 1 + 1 file changed, 1 insertion(+)
diff --git a/drivers/vfio/vfio.c b/drivers/vfio/vfio.c index 0d73d913c18b..747eb5c70238 100644 --- a/drivers/vfio/vfio.c +++ b/drivers/vfio/vfio.c @@ -1813,6 +1813,7 @@ 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); }