[PATCH 060/150] tools: hv: Netlink source address validation allows DoS

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



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

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

From: Tomas Hozza <thozza@xxxxxxxxxx>

commit 95a69adab9acfc3981c504737a2b6578e4d846ef upstream.

The source code without this patch caused hypervkvpd to exit when it processed
a spoofed Netlink packet which has been sent from an untrusted local user.
Now Netlink messages with a non-zero nl_pid source address are ignored
and a warning is printed into the syslog.

Signed-off-by: Tomas Hozza <thozza@xxxxxxxxxx>
Acked-by:  K. Y. Srinivasan <kys@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
Signed-off-by: Luis Henriques <luis.henriques@xxxxxxxxxxxxx>
---
 tools/hv/hv_kvp_daemon.c | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/tools/hv/hv_kvp_daemon.c b/tools/hv/hv_kvp_daemon.c
index 2984ffb..60a8e29 100644
--- a/tools/hv/hv_kvp_daemon.c
+++ b/tools/hv/hv_kvp_daemon.c
@@ -727,13 +727,19 @@ int main(void)
 		len = recvfrom(fd, kvp_recv_buffer, sizeof(kvp_recv_buffer), 0,
 				addr_p, &addr_l);
 
-		if (len < 0 || addr.nl_pid) {
+		if (len < 0) {
 			syslog(LOG_ERR, "recvfrom failed; pid:%u error:%d %s",
 					addr.nl_pid, errno, strerror(errno));
 			close(fd);
 			return -1;
 		}
 
+		if (addr.nl_pid) {
+			syslog(LOG_WARNING, "Received packet from untrusted pid:%u",
+					addr.nl_pid);
+			continue;
+		}
+
 		incoming_msg = (struct nlmsghdr *)kvp_recv_buffer;
 		incoming_cn_msg = (struct cn_msg *)NLMSG_DATA(incoming_msg);
 		hv_msg = (struct hv_kvp_msg *)incoming_cn_msg->data;
-- 
1.8.1.2

--
To unsubscribe from this list: send the line "unsubscribe stable" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html




[Index of Archives]     [Linux Kernel]     [Kernel Development Newbies]     [Linux USB Devel]     [Video for Linux]     [Linux Audio Users]     [Yosemite Hiking]     [Linux Kernel]     [Linux SCSI]