[LTP] [PATCH v6] Add test for CVE-2017-7308 on a raw socket's ring buffer

[LTP] [PATCH v6] Add test for CVE-2017-7308 on a raw socket's ring buffer

[Richard Palethorpe]

This test uses a Linux only interface which has not been fully integrated into
glibc and it is not clear if it ever will be. So I have kept the fallback
logic relatively simple and use only the Linux headers if they are present or
just define what is needed in the test.

Signed-off-by: Richard Palethorpe <rpalethorpe@suse.com>
---

V6 - I have set the block size to a single page, to make it page aligned on
     all systems. It was failing on PPC64.

 configure.ac                  |   3 +
 m4/ltp-tpacket-v3.m4          |  22 +++++++
 runtest/cve                   |   1 +
 testcases/cve/.gitignore      |   1 +
 testcases/cve/cve-2017-7308.c | 145 ++++++++++++++++++++++++++++++++++++++++++
 5 files changed, 172 insertions(+)
 create mode 100644 m4/ltp-tpacket-v3.m4
 create mode 100644 testcases/cve/cve-2017-7308.c

diff --git a/configure.ac b/configure.ac
index 82ebfc8da..834bdba62 100644
--- a/configure.ac
+++ b/configure.ac
@@ -37,6 +37,8 @@ AC_CHECK_HEADERS([ \
     pthread.h \
     sys/xattr.h \
     linux/genetlink.h \
+    linux/if_packet.h \
+    linux/if_ether.h \
     linux/mempolicy.h \
     linux/module.h \
     linux/netlink.h \
@@ -199,5 +201,6 @@ LTP_CHECK_MMSGHDR
 LTP_CHECK_UNAME_DOMAINNAME
 LTP_CHECK_X_TABLES
 LTP_CHECK_ATOMIC_MEMORY_MODEL
+LTP_CHECK_TPACKET_V3
 
 AC_OUTPUT
diff --git a/m4/ltp-tpacket-v3.m4 b/m4/ltp-tpacket-v3.m4
new file mode 100644
index 000000000..fce2e0ebf
--- /dev/null
+++ b/m4/ltp-tpacket-v3.m4
@@ -0,0 +1,22 @@
+dnl Copyright (c) 2017 Richard Palethorpe <rpalethorpe@suse.com>
+dnl
+dnl This program is free software;  you can redistribute it and/or modify
+dnl it under the terms of the GNU General Public License as published by
+dnl the Free Software Foundation; either version 2 of the License, or
+dnl (at your option) any later version.
+dnl
+dnl This program is distributed in the hope that it will be useful,
+dnl but WITHOUT ANY WARRANTY;  without even the implied warranty of
+dnl MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See
+dnl the GNU General Public License for more details.
+dnl
+dnl You should have received a copy of the GNU General Public License
+dnl along with this program. If not, see <http://www.gnu.org/licenses/>.
+
+AC_DEFUN([LTP_CHECK_TPACKET_V3],[
+AC_CHECK_TYPES([struct tpacket_req3],,,[
+#ifdef HAVE_LINUX_IF_PACKET_H
+# include <linux/if_packet.h>
+#endif
+])
+])
diff --git a/runtest/cve b/runtest/cve
index d182e592a..97f1ddded 100644
--- a/runtest/cve
+++ b/runtest/cve
@@ -16,6 +16,7 @@ cve-2017-2618 cve-2017-2618
 cve-2017-2671 cve-2017-2671
 cve-2017-5669 cve-2017-5669
 cve-2017-6951 cve-2017-6951
+cve-2017-7308 cve-2017-7308
 cve-2017-7472 keyctl04
 cve-2017-15274 add_key02
 cve-2017-1000364 stack_clash
diff --git a/testcases/cve/.gitignore b/testcases/cve/.gitignore
index f76c39826..c04d1c9a1 100644
--- a/testcases/cve/.gitignore
+++ b/testcases/cve/.gitignore
@@ -8,4 +8,5 @@ cve-2017-2618
 cve-2017-2671
 cve-2017-6951
 cve-2017-5669
+cve-2017-7308
 stack_clash
diff --git a/testcases/cve/cve-2017-7308.c b/testcases/cve/cve-2017-7308.c
new file mode 100644
index 000000000..d825f3a65
--- /dev/null
+++ b/testcases/cve/cve-2017-7308.c
@@ -0,0 +1,145 @@
+/*
+ * Copyright (c) 2017 Richard Palethorpe <rpalethorpe@suse.com>
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+/* Test for CVE-2017-7308 on a raw socket's ring buffer
+ *
+ * Try to set tpacket_req3.tp_sizeof_priv to a value with the high bit set. So
+ * that tp_block_size < tp_sizeof_priv. If the vulnerability is present then
+ * this will cause an integer arithmatic overflow and the absurd
+ * tp_sizeof_priv value will be allowed. If it has been fixed then setsockopt
+ * will fail with EINVAL.
+ *
+ * We also try a good configuration to make sure it is not failing with EINVAL
+ * for some other reason.
+ *
+ * For a better and more interesting discussion of this CVE see:
+ * https://googleprojectzero.blogspot.com/2017/05/exploiting-linux-kernel-via-packet.html
+ */
+
+#include <errno.h>
+#include "tst_test.h"
+#include "tst_safe_net.h"
+#include "config.h"
+
+#ifdef HAVE_LINUX_IF_PACKET_H
+# include <linux/if_packet.h>
+#endif
+
+#ifdef HAVE_LINUX_IF_ETHER_H
+# include <linux/if_ether.h>
+#endif
+
+#ifndef ETH_P_ALL
+# define ETH_P_ALL 0x0003
+#endif
+
+#ifndef PACKET_RX_RING
+# define PACKET_RX_RING 5
+#endif
+
+#ifndef PACKET_VERSION
+# define PACKET_VERSION 10
+#endif
+
+#ifndef HAVE_STRUCT_TPACKET_REQ3
+# define TPACKET_V3 2
+
+struct tpacket_req3 {
+	unsigned int	tp_block_size;
+	unsigned int	tp_block_nr;
+	unsigned int	tp_frame_size;
+	unsigned int	tp_frame_nr;
+	unsigned int	tp_retire_blk_tov;
+	unsigned int	tp_sizeof_priv;
+	unsigned int	tp_feature_req_word;
+};
+#endif
+
+static int sk;
+static long pgsz;
+
+static void setup(void)
+{
+	pgsz = SAFE_SYSCONF(_SC_PAGESIZE);
+}
+
+static void cleanup(void)
+{
+	if (sk > 0)
+		SAFE_CLOSE(sk);
+}
+
+static int create_skbuf(unsigned int sizeof_priv)
+{
+	int ver = TPACKET_V3;
+	struct tpacket_req3 req = {};
+
+	req.tp_block_size = pgsz;
+	req.tp_block_nr = 2;
+	req.tp_frame_size = req.tp_block_size;
+	req.tp_frame_nr = req.tp_block_nr;
+	req.tp_retire_blk_tov = 100;
+
+	req.tp_sizeof_priv = sizeof_priv;
+
+	sk = SAFE_SOCKET(AF_PACKET, SOCK_RAW, htons(ETH_P_ALL));
+	TEST(setsockopt(sk, SOL_PACKET, PACKET_VERSION, &ver, sizeof(ver)));
+	if (TEST_RETURN && TEST_ERRNO == EINVAL)
+		tst_brk(TCONF | TTERRNO, "TPACKET_V3 not supported");
+	if (TEST_RETURN)
+		tst_brk(TBROK | TTERRNO, "setsockopt(sk, SOL_PACKET, PACKET_VERSION, TPACKET_V3)");
+
+	return setsockopt(sk, SOL_PACKET, PACKET_RX_RING, &req, sizeof(req));
+}
+
+static void good_size(void)
+{
+	TEST(create_skbuf(512));
+	if (TEST_RETURN)
+		tst_brk(TBROK | TTERRNO, "Can't create ring buffer with good settings");
+
+	tst_res(TPASS, "Can create ring buffer with good settinegs");
+}
+
+static void bad_size(void)
+{
+	TEST(create_skbuf(3U << 30));
+	if (TEST_RETURN && TEST_ERRNO != EINVAL)
+		tst_brk(TBROK | TTERRNO, "Unexpected setsockopt() error");
+	if (TEST_RETURN)
+		tst_res(TPASS | TTERRNO, "Refused bad tp_sizeof_priv value");
+	else
+		tst_res(TFAIL, "Allowed bad tp_sizeof_priv value");
+}
+
+static void run(unsigned int i)
+{
+	if (i == 0)
+		good_size();
+	else
+		bad_size();
+
+	SAFE_CLOSE(sk);
+}
+
+static struct tst_test test = {
+	.test = run,
+	.tcnt = 2,
+	.needs_root = 1,
+	.setup = setup,
+	.cleanup = cleanup,
+	.min_kver = "3.2",
+};
-- 
2.14.2

[LTP] [PATCH v6] Add test for CVE-2017-7308 on a raw socket's ring buffer

[Cyril Hrubis]

Hi!
> diff --git a/testcases/cve/cve-2017-7308.c b/testcases/cve/cve-2017-7308.c
> new file mode 100644
> index 000000000..d825f3a65
> --- /dev/null
> +++ b/testcases/cve/cve-2017-7308.c
> @@ -0,0 +1,145 @@
> +/*
> + * Copyright (c) 2017 Richard Palethorpe <rpalethorpe@suse.com>
> + *
> + * This program is free software: you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License as published by
> + * the Free Software Foundation, either version 2 of the License, or
> + * (at your option) any later version.
> + *
> + * This program is distributed in the hope that it will be useful,
> + * but WITHOUT ANY WARRANTY; without even the implied warranty of
> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
> + * GNU General Public License for more details.
> + *
> + * You should have received a copy of the GNU General Public License
> + * along with this program. If not, see <http://www.gnu.org/licenses/>.
> + */
> +/* Test for CVE-2017-7308 on a raw socket's ring buffer
> + *
> + * Try to set tpacket_req3.tp_sizeof_priv to a value with the high bit set. So
> + * that tp_block_size < tp_sizeof_priv. If the vulnerability is present then
> + * this will cause an integer arithmatic overflow and the absurd
                                 ^
				 typo
> + * tp_sizeof_priv value will be allowed. If it has been fixed then setsockopt
> + * will fail with EINVAL.
> + *
> + * We also try a good configuration to make sure it is not failing with EINVAL
> + * for some other reason.
> + *
> + * For a better and more interesting discussion of this CVE see:
> + * https://googleprojectzero.blogspot.com/2017/05/exploiting-linux-kernel-via-packet.html
> + */
> +
> +#include <errno.h>
> +#include "tst_test.h"
> +#include "tst_safe_net.h"
> +#include "config.h"
> +
> +#ifdef HAVE_LINUX_IF_PACKET_H
> +# include <linux/if_packet.h>
> +#endif
> +
> +#ifdef HAVE_LINUX_IF_ETHER_H
> +# include <linux/if_ether.h>
> +#endif
> +
> +#ifndef ETH_P_ALL
> +# define ETH_P_ALL 0x0003
> +#endif
> +
> +#ifndef PACKET_RX_RING
> +# define PACKET_RX_RING 5
> +#endif
> +
> +#ifndef PACKET_VERSION
> +# define PACKET_VERSION 10
> +#endif
> +
> +#ifndef HAVE_STRUCT_TPACKET_REQ3
> +# define TPACKET_V3 2
> +
> +struct tpacket_req3 {
> +	unsigned int	tp_block_size;
> +	unsigned int	tp_block_nr;
> +	unsigned int	tp_frame_size;
> +	unsigned int	tp_frame_nr;
> +	unsigned int	tp_retire_blk_tov;
> +	unsigned int	tp_sizeof_priv;
> +	unsigned int	tp_feature_req_word;
> +};
> +#endif
> +
> +static int sk;
> +static long pgsz;
> +
> +static void setup(void)
> +{
> +	pgsz = SAFE_SYSCONF(_SC_PAGESIZE);
> +}
> +
> +static void cleanup(void)
> +{
> +	if (sk > 0)
> +		SAFE_CLOSE(sk);
> +}
> +
> +static int create_skbuf(unsigned int sizeof_priv)
> +{
> +	int ver = TPACKET_V3;
> +	struct tpacket_req3 req = {};
> +
> +	req.tp_block_size = pgsz;
> +	req.tp_block_nr = 2;
> +	req.tp_frame_size = req.tp_block_size;
> +	req.tp_frame_nr = req.tp_block_nr;
> +	req.tp_retire_blk_tov = 100;
> +
> +	req.tp_sizeof_priv = sizeof_priv;
> +
> +	sk = SAFE_SOCKET(AF_PACKET, SOCK_RAW, htons(ETH_P_ALL));
> +	TEST(setsockopt(sk, SOL_PACKET, PACKET_VERSION, &ver, sizeof(ver)));
> +	if (TEST_RETURN && TEST_ERRNO == EINVAL)
> +		tst_brk(TCONF | TTERRNO, "TPACKET_V3 not supported");
> +	if (TEST_RETURN)
> +		tst_brk(TBROK | TTERRNO, "setsockopt(sk, SOL_PACKET, PACKET_VERSION, TPACKET_V3)");
> +
> +	return setsockopt(sk, SOL_PACKET, PACKET_RX_RING, &req, sizeof(req));
> +}

Also I wonder if we should put it under syscalls/setsockopt(). Maybe we
should adopt a rule that if it's reasonably clear which syscall the test
belongs to we would put it into the syscalls/ directory and use the cve
directory as a fallback for all the rest of the cve reproducers. What do
you think?

-- 
Cyril Hrubis
chrubis@suse.cz

[LTP] [PATCH v6] Add test for CVE-2017-7308 on a raw socket's ring buffer

[Richard Palethorpe]

Hello,

Cyril Hrubis writes:

>
> Also I wonder if we should put it under syscalls/setsockopt(). Maybe we
> should adopt a rule that if it's reasonably clear which syscall the test
> belongs to we would put it into the syscalls/ directory and use the cve
> directory as a fallback for all the rest of the cve reproducers. What do
> you think?

I'm happy with that. I like having all the CVE tests in one place, but
the runtest file appears to do a good enough job of that. 

-- 
Thank you,
Richard.