[ 02/48] Tools: hv: verify origin of netlink connector message

Ben Hutchings
2012-07-01T18:27:42Z

From: Olaf Hering <olaf@aepfle.de>

commit bcc2c9c3fff859e0eb019fe6fec26f9b8eba795c upstream.

The SuSE security team suggested to use recvfrom instead of recv to be
certain that the connector message is originated from kernel.

CVE-2012-2669

Signed-off-by: Olaf Hering <olaf@aepfle.de>
Signed-off-by: Marcus Meissner <meissner@suse.de>
Signed-off-by: Sebastian Krahmer <krahmer@suse.de>
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
---
tools/hv/hv_kvp_daemon.c | 10 +++++++---
1 file changed, 7 insertions(+), 3 deletions(-)

diff --git a/tools/hv/hv_kvp_daemon.c b/tools/hv/hv_kvp_daemon.c
index 146fd61..d9834b3 100644
--- a/tools/hv/hv_kvp_daemon.c
+++ b/tools/hv/hv_kvp_daemon.c
@@ -701,14 +701,18 @@ int main(void)
pfd.fd = fd;

while (1) {
+ struct sockaddr *addr_p = (struct sockaddr *) &addr;
+ socklen_t addr_l = sizeof(addr);
pfd.events = POLLIN;
pfd.revents = 0;
poll(&pfd, 1, -1);

- len = recv(fd, kvp_recv_buffer, sizeof(kvp_recv_buffer), 0);
+ len = recvfrom(fd, kvp_recv_buffer, sizeof(kvp_recv_buffer), 0,
+ addr_p, &addr_l);

- if (len < 0) {
- syslog(LOG_ERR, "recv failed; error:%d", len);
+ if (len < 0 || addr.nl_pid) {
+ syslog(LOG_ERR, "recvfrom failed; pid:%u error:%d %s",
+ addr.nl_pid, errno, strerror(errno));
close(fd);
return -1;
}