lkml.org 
[lkml]   [2017]   [Apr]   [16]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH 4.10 28/29] net/packet: fix overflow in check for priv area size
Date
4.10-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Andrey Konovalov <andreyknvl@google.com>

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>

---
net/packet/af_packet.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

--- a/net/packet/af_packet.c
+++ b/net/packet/af_packet.c
@@ -4177,8 +4177,8 @@ static int packet_set_ring(struct sock *
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 +
po->tp_reserve))

\
 
 \ /
  Last update: 2017-04-16 10:09    [W:0.105 / U:5.452 seconds]
©2003-2018 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site