| Message ID | 20190210085712.31622-1-kal.conley@dectris.com |
|---|---|
| State | Accepted |
| Delegated to: | David Miller |
| Headers | show |
| Series | [v2] net/packet: fix 4gb buffer limit due to overflow check | expand |
From: Kal Conley <kal.conley@dectris.com> Date: Sun, 10 Feb 2019 09:57:11 +0100 > 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: 8f8d28e4d6d8 ("net/packet: fix overflow in check for tp_frame_nr") > Signed-off-by: Kal Conley <kal.conley@dectris.com> > --- > Changes in v2: > - Add Signed-off-by and Fixes tag Applied and queued up for -stable, thanks.
diff --git a/net/packet/af_packet.c b/net/packet/af_packet.c index 3b1a78906bc0..1cd1d83a4be0 100644 --- a/net/packet/af_packet.c +++ b/net/packet/af_packet.c @@ -4292,7 +4292,7 @@ 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))
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: 8f8d28e4d6d8 ("net/packet: fix overflow in check for tp_frame_nr") Signed-off-by: Kal Conley <kal.conley@dectris.com> --- Changes in v2: - Add Signed-off-by and Fixes tag net/packet/af_packet.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)