linux-kernel - [PATCH net-next,3/6] hyperv: Fix page buffer handling in rndis_filter_send

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]

Date:	Tue,  2 Oct 2012 08:30:21 -0700
From:	Haiyang Zhang <haiyangz@...rosoft.com>
To:	davem@...emloft.net, netdev@...r.kernel.org
Cc:	haiyangz@...rosoft.com, kys@...rosoft.com, olaf@...fle.de,
	jasowang@...hat.com, linux-kernel@...r.kernel.org,
	devel@...uxdriverproject.org
Subject: [PATCH net-next,3/6] hyperv: Fix page buffer handling in rndis_filter_send_request()

To prevent possible data corruption in RNDIS requests, add another
page buffer if the request message crossed page boundary.

Signed-off-by: Haiyang Zhang <haiyangz@...rosoft.com>
Reviewed-by: K. Y. Srinivasan <kys@...rosoft.com>

---
 drivers/net/hyperv/rndis_filter.c |   15 ++++++++++++++-
 1 files changed, 14 insertions(+), 1 deletions(-)

diff --git a/drivers/net/hyperv/rndis_filter.c b/drivers/net/hyperv/rndis_filter.c
index 617eb2e..f25f41e 100644
--- a/drivers/net/hyperv/rndis_filter.c
+++ b/drivers/net/hyperv/rndis_filter.c
@@ -45,7 +45,8 @@ struct rndis_request {
 
 	/* Simplify allocation by having a netvsc packet inline */
 	struct hv_netvsc_packet	pkt;
-	struct hv_page_buffer buf;
+	/* Set 2 pages for rndis requests crossing page boundary */
+	struct hv_page_buffer buf[2];
 
 	struct rndis_message request_msg;
 	/*
@@ -227,6 +228,18 @@ static int rndis_filter_send_request(struct rndis_device *dev,
 	packet->page_buf[0].offset =
 		(unsigned long)&req->request_msg & (PAGE_SIZE - 1);
 
+	/* Add one page_buf when request_msg crossing page boundary */
+	if (packet->page_buf[0].offset + packet->page_buf[0].len > PAGE_SIZE) {
+		packet->page_buf_cnt++;
+		packet->page_buf[0].len = PAGE_SIZE -
+			packet->page_buf[0].offset;
+		packet->page_buf[1].pfn = virt_to_phys((void *)&req->request_msg
+			+ packet->page_buf[0].len) >> PAGE_SHIFT;
+		packet->page_buf[1].offset = 0;
+		packet->page_buf[1].len = req->request_msg.msg_len -
+			packet->page_buf[0].len;
+	}
+
 	packet->completion.send.send_completion_ctx = req;/* packet; */
 	packet->completion.send.send_completion =
 		rndis_filter_send_request_completion;
-- 
1.7.4.1

--
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/