3.2.89-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: Andrey Konovalov <andreyknvl@xxxxxxxxxx> commit 8f8d28e4d6d815a391285e121c3a53a0b6cb9e7b upstream. When calculating rb->frames_per_block * req->tp_block_nr the result can overflow. Add a check that tp_block_size * tp_block_nr <= UINT_MAX. Since frames_per_block <= tp_block_size, the expression would never overflow. Signed-off-by: Andrey Konovalov <andreyknvl@xxxxxxxxxx> Acked-by: Eric Dumazet <edumazet@xxxxxxxxxx> Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx> Signed-off-by: Ben Hutchings <ben@xxxxxxxxxxxxxxx> --- net/packet/af_packet.c | 2 ++ 1 file changed, 2 insertions(+) --- a/net/packet/af_packet.c +++ b/net/packet/af_packet.c @@ -3649,6 +3649,8 @@ static int packet_set_ring(struct sock * rb->frames_per_block = req->tp_block_size/req->tp_frame_size; if (unlikely(rb->frames_per_block <= 0)) goto out; + if (unlikely(req->tp_block_size > UINT_MAX / req->tp_block_nr)) + goto out; if (unlikely((rb->frames_per_block * req->tp_block_nr) != req->tp_frame_nr)) goto out;