On 19/07/2019 18:03, Eric Blake wrote: > We've had two separate reports of a caller running into use of > uninitialized data if s->quit is set (one detected by gcc -O3, another > by valgrind), due to checking 'nbd_reply_is_simple(reply) || s->quit' > in the wrong order. Rather than chasing down which callers need to > pre-initialize reply, it's easier to guarantee that reply will always > be set by nbd_co_receive_one_chunk() even on failure. > > Reported-by: Thomas Huth <th...@redhat.com> > Reported-by: Andrey Shinkevich <andrey.shinkev...@virtuozzo.com> > Signed-off-by: Eric Blake <ebl...@redhat.com> > --- > > Replaces: https://lists.gnu.org/archive/html/qemu-devel/2019-07/msg04477.html > Replaces: https://lists.gnu.org/archive/html/qemu-devel/2019-07/msg03712.html > > block/nbd.c | 1 + > 1 file changed, 1 insertion(+) > > diff --git a/block/nbd.c b/block/nbd.c > index 8d565cc624ec..f751a8e633e5 100644 > --- a/block/nbd.c > +++ b/block/nbd.c > @@ -640,6 +640,7 @@ static coroutine_fn int nbd_co_receive_one_chunk( > request_ret, qiov, payload, errp); > > if (ret < 0) { > + memset(reply, 0, sizeof *reply); > s->quit = true; > } else { > /* For assert at loop start in nbd_connection_entry */ >
Reviewed-by: Andrey Shinkevich <andrey.shinkev...@virtuozzo.com> -- With the best regards, Andrey Shinkevich
