On Thu, Oct 08, 2020 at 06:13:11PM +0200, Stefano Garzarella wrote:
If riov and wiov are both defined and they point to different objects, only riov is initialized. If the wiov is not initialized by the caller, the function fails returning -EINVAL and printing "Readable desc 0x... after writable" error message.
Let's replace the 'else if' clause with 'if' to initialize both riov and wiov if they are not NULL.
As checkpatch pointed out, we also avoid crashing the kernel when riov and wiov are both NULL, replacing BUG() with WARN_ON() and returning -EINVAL.
Fixes: f87d0fbb5798 ("vringh: host-side implementation of virtio rings.") Cc: stable@vger.kernel.org Signed-off-by: Stefano Garzarella sgarzare@redhat.com
Can you add more detail please? when does this trigger?
drivers/vhost/vringh.c | 9 +++++---- 1 file changed, 5 insertions(+), 4 deletions(-)
diff --git a/drivers/vhost/vringh.c b/drivers/vhost/vringh.c index e059a9a47cdf..8bd8b403f087 100644 --- a/drivers/vhost/vringh.c +++ b/drivers/vhost/vringh.c @@ -284,13 +284,14 @@ __vringh_iov(struct vringh *vrh, u16 i, desc_max = vrh->vring.num; up_next = -1;
- /* You must want something! */
- if (WARN_ON(!riov && !wiov))
return -EINVAL;- if (riov) riov->i = riov->used = 0;
- else if (wiov)
- if (wiov) wiov->i = wiov->used = 0;
- else
/* You must want something! */BUG();for (;;) { void *addr; -- 2.26.2