linux-kernel - [ 28/56] macvtap: zerocopy: validate vectors before building skb

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <20130402224715.152114862@linuxfoundation.org>
Date:	Tue,  2 Apr 2013 15:49:55 -0700
From:	Greg Kroah-Hartman <gregkh@...uxfoundation.org>
To:	linux-kernel@...r.kernel.org
Cc:	Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
	stable@...r.kernel.org, Jason Wang <jasowang@...hat.com>,
	"Michael S. Tsirkin" <mst@...hat.com>, Jiri Slaby <jslaby@...e.cz>,
	Benjamin Poirier <bpoirier@...e.de>
Subject: [ 28/56] macvtap: zerocopy: validate vectors before building skb

3.0-stable review patch.  If anyone has any objections, please let me know.

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


From: Jason Wang <jasowang@...hat.com>

commit b92946e2919134ebe2a4083e4302236295ea2a73 upstream.

There're several reasons that the vectors need to be validated:

- Return error when caller provides vectors whose num is greater than UIO_MAXIOV.
- Linearize part of skb when userspace provides vectors grater than MAX_SKB_FRAGS.
- Return error when userspace provides vectors whose total length may exceed
- MAX_SKB_FRAGS * PAGE_SIZE.

Signed-off-by: Jason Wang <jasowang@...hat.com>
Signed-off-by: Michael S. Tsirkin <mst@...hat.com>
Signed-off-by: Benjamin Poirier <bpoirier@...e.de> [patch reduced to
					the 3rd reason only for 3.0]
Signed-off-by: Jiri Slaby <jslaby@...e.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@...uxfoundation.org>
---
 drivers/net/macvtap.c |    4 ++++
 1 file changed, 4 insertions(+)

--- a/drivers/net/macvtap.c
+++ b/drivers/net/macvtap.c
@@ -552,6 +552,10 @@ static ssize_t macvtap_get_user(struct m
 	if (unlikely(len < ETH_HLEN))
 		goto err;
 
+	err = -EMSGSIZE;
+	if (unlikely(count > UIO_MAXIOV))
+		goto err;
+
 	skb = macvtap_alloc_skb(&q->sk, NET_IP_ALIGN, len, vnet_hdr.hdr_len,
 				noblock, &err);
 	if (!skb)


--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/