[4.4,21/43] net/packet: fix overflow in check for tp_frame_nr
diff mbox series

Message ID 20170501212600.391800515@linuxfoundation.org
State New, archived
Headers show
Series
  • 4.4.66-stable review
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Commit Message

Greg KH May 1, 2017, 9:27 p.m. UTC
4.4-stable review patch.  If anyone has any objections, please let me know.

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

From: Andrey Konovalov <andreyknvl@google.com>


[ Upstream commit 8f8d28e4d6d815a391285e121c3a53a0b6cb9e7b ]

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@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 |    2 ++
 1 file changed, 2 insertions(+)

Patch
diff mbox series

--- a/net/packet/af_packet.c
+++ b/net/packet/af_packet.c
@@ -4150,6 +4150,8 @@  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;