Home Home > GIT Browse
diff options
authorAndrey Konovalov <andreyknvl@google.com>2017-03-29 16:11:20 +0200
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2017-04-18 06:59:35 +0200
commit10e13823b0a984d3184031e292d15a99cb4c0b81 (patch)
parent50d60091d2940c8bf87d55592ced39b2da4fd013 (diff)
net/packet: fix overflow in check for priv area size
commit 2b6867c2ce76c596676bec7d2d525af525fdc6e2 upstream. Subtracting tp_sizeof_priv from tp_block_size and casting to int to check whether one is less then the other doesn't always work (both of them are unsigned ints). Compare them as is instead. Also cast tp_sizeof_priv to u64 before using BLK_PLUS_PRIV, as it can overflow inside BLK_PLUS_PRIV otherwise. Signed-off-by: Andrey Konovalov <andreyknvl@google.com> Acked-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
1 files changed, 2 insertions, 2 deletions
diff --git a/net/packet/af_packet.c b/net/packet/af_packet.c
index c59fcc79ba32..5c919933a39b 100644
--- a/net/packet/af_packet.c
+++ b/net/packet/af_packet.c
@@ -4177,8 +4177,8 @@ static int packet_set_ring(struct sock *sk, union tpacket_req_u *req_u,
if (unlikely(!PAGE_ALIGNED(req->tp_block_size)))
goto out;
if (po->tp_version >= TPACKET_V3 &&
- (int)(req->tp_block_size -
- BLK_PLUS_PRIV(req_u->req3.tp_sizeof_priv)) <= 0)
+ req->tp_block_size <=
+ BLK_PLUS_PRIV((u64)req_u->req3.tp_sizeof_priv))
goto out;
if (unlikely(req->tp_frame_size < po->tp_hdrlen +