From patchwork Wed Jan 9 12:35:12 2013 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Subject: [Oneiric, CVE, 1/1] tools: hv: Netlink source address validation allows DoS From: Luis Henriques X-Patchwork-Id: 210710 Message-Id: <1357734912-18355-2-git-send-email-luis.henriques@canonical.com> To: kernel-team@lists.ubuntu.com Date: Wed, 9 Jan 2013 12:35:12 +0000 From: Tomas Hozza CVE-2012-5532 BugLink: http://bugs.launchpad.net/bugs/1084777 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 Acked-by: K. Y. Srinivasan Signed-off-by: Greg Kroah-Hartman (backported from commit 95a69adab9acfc3981c504737a2b6578e4d846ef) Signed-off-by: Luis Henriques Conflicts: tools/hv/hv_kvp_daemon.c --- drivers/staging/hv/tools/hv_kvp_daemon.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) diff --git a/drivers/staging/hv/tools/hv_kvp_daemon.c b/drivers/staging/hv/tools/hv_kvp_daemon.c index 1468a01..6399451 100644 --- a/drivers/staging/hv/tools/hv_kvp_daemon.c +++ b/drivers/staging/hv/tools/hv_kvp_daemon.c @@ -387,13 +387,19 @@ 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);