Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit c2ee2c70 authored by Kal Conley's avatar Kal Conley Committed by Greg Kroah-Hartman
Browse files

net/packet: fix 4gb buffer limit due to overflow check 



[ Upstream commit fc62814d690cf62189854464f4bd07457d5e9e50 ]

When calculating rb->frames_per_block * req->tp_block_nr the result
can overflow. Check it for overflow without limiting the total buffer
size to UINT_MAX.

This change fixes support for packet ring buffers >= UINT_MAX.

Fixes: 8f8d28e4 ("net/packet: fix overflow in check for tp_frame_nr")
Signed-off-by: default avatarKal Conley <kal.conley@dectris.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent f3ec82db

net/packet/af_packet.c

+1 −1
Original line number Diff line number Diff line
@@ -4275,7 +4275,7 @@ static int packet_set_ring(struct sock *sk, union tpacket_req_u *req_u, 
		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))

		if (unlikely(rb->frames_per_block > UINT_MAX / req->tp_block_nr))

			goto out;

		if (unlikely((rb->frames_per_block * req->tp_block_nr) !=

					req->tp_frame_nr))