tests: introduce midtail_alloc and use it in netlink tests

netlink tests happen to access memory located before the tail_malloc'ed
pointers, a practice that doesn't go well with the latest compilers
because tail_malloc is marked with ATTRIBUTE_MALLOC.
For example, glibc in -D_FORTIFY_SOURCE=2 mode and gcc 8 with
-Warray-bounds enabled complain about negative offsets out of bounds.
Fix this issue by introducing midtail_alloc.

* tests/tests.h (midtail_alloc): New macro.
* tests/netlink_crypto.c: Use it instead of tail_malloc for nlh0 allocation.
* tests/netlink_netfilter.c: Likewise.
* tests/netlink_protocol.c: Likewise.
* tests/netlink_route.c: Likewise.
* tests/netlink_selinux.c: Likewise.
* tests/netlink_sock_diag.c: Likewise.
* tests/nlattr_br_port_msg.c: Likewise.
* tests/nlattr_crypto_user_alg.c: Likewise.
* tests/nlattr_dcbmsg.c: Likewise.
* tests/nlattr_fib_rule_hdr.c: Likewise.
* tests/nlattr_ifaddrlblmsg.c: Likewise.
* tests/nlattr_ifaddrmsg.c: Likewise.
* tests/nlattr_ifinfomsg.c: Likewise.
* tests/nlattr_ifla_brport.c: Likewise.
* tests/nlattr_ifla_port.c: Likewise.
* tests/nlattr_ifla_xdp.c: Likewise.
* tests/nlattr_inet_diag_msg.c: Likewise.
* tests/nlattr_inet_diag_req_compat.c: Likewise.
* tests/nlattr_inet_diag_req_v2.c: Likewise.
* tests/nlattr_mdba_mdb_entry.c: Likewise.
* tests/nlattr_mdba_router_port.c: Likewise.
* tests/nlattr_ndmsg.c: Likewise.
* tests/nlattr_ndtmsg.c: Likewise.
* tests/nlattr_netconfmsg.c: Likewise.
* tests/nlattr_netlink_diag_msg.c: Likewise.
* tests/nlattr_nlmsgerr.c: Likewise.
* tests/nlattr_packet_diag_msg.c: Likewise.
* tests/nlattr_rtgenmsg.c: Likewise.
* tests/nlattr_rtmsg.c: Likewise.
* tests/nlattr_smc_diag_msg.c: Likewise.
* tests/nlattr_tc_stats.c: Likewise.
* tests/nlattr_tca_stab.c: Likewise.
* tests/nlattr_tcamsg.c: Likewise.
* tests/nlattr_tcmsg.c: Likewise.
* tests/nlattr_unix_diag_msg.c: Likewise.

Co-Authored-by: Dmitry V. Levin <ldv@altlinux.org>

1 files changed, 18 insertions, 18 deletions

diff --git a/tests/netlink_sock_diag.c b/tests/netlink_sock_diag.c
index c2ebf129c..c9e1232f9 100644
--- a/tests/netlink_sock_diag.c
+++ b/tests/netlink_sock_diag.c
@@ -127,10 +127,11 @@ test_nlmsg_flags(const int fd)
 static void
 test_odd_family_req(const int fd)
 {
-	void *const nlh0 = tail_alloc(NLMSG_HDRLEN);
+	uint8_t family = 0;
+	char buf[sizeof(family) + 4];
+	void *const nlh0 = midtail_alloc(NLMSG_HDRLEN, sizeof(buf));
 
 	/* unspecified family only */
-	uint8_t family = 0;
 	TEST_NETLINK(fd, nlh0,
 		     SOCK_DIAG_BY_FAMILY,
 		     NLM_F_REQUEST,
@@ -153,7 +154,6 @@ test_odd_family_req(const int fd)
 		     printf("%p", NLMSG_DATA(TEST_NETLINK_nlh)));
 
 	/* unspecified family and string */
-	char buf[sizeof(family) + 4];
 	family = 0;
 	memcpy(buf, &family, sizeof(family));
 	memcpy(buf + sizeof(family), "1234", 4);
@@ -177,10 +177,11 @@ test_odd_family_req(const int fd)
 static void
 test_odd_family_msg(const int fd)
 {
-	void *const nlh0 = tail_alloc(NLMSG_HDRLEN);
+	uint8_t family = 0;
+	char buf[sizeof(family) + 4];
+	void *const nlh0 = midtail_alloc(NLMSG_HDRLEN, sizeof(buf));
 
 	/* unspecified family only */
-	uint8_t family = 0;
 	TEST_NETLINK(fd, nlh0,
 		     SOCK_DIAG_BY_FAMILY, NLM_F_DUMP,
 		     sizeof(family), &family, sizeof(family),
@@ -200,7 +201,6 @@ test_odd_family_msg(const int fd)
 		     printf("%p", NLMSG_DATA(TEST_NETLINK_nlh)));
 
 	/* unspecified family and string */
-	char buf[sizeof(family) + 4];
 	family = 0;
 	memcpy(buf, &family, sizeof(family));
 	memcpy(buf + sizeof(family), "1234", 4);
@@ -222,7 +222,6 @@ test_odd_family_msg(const int fd)
 static void
 test_unix_diag_req(const int fd)
 {
-	void *const nlh0 = tail_alloc(NLMSG_HDRLEN);
 	static const struct unix_diag_req req = {
 		.sdiag_family = AF_UNIX,
 		.sdiag_protocol = 253,
@@ -231,6 +230,7 @@ test_unix_diag_req(const int fd)
 		.udiag_show = UDIAG_SHOW_NAME,
 		.udiag_cookie = { 0xdeadbeef, 0xbadc0ded }
 	};
+	void *const nlh0 = midtail_alloc(NLMSG_HDRLEN, sizeof(req));
 	TEST_SOCK_DIAG(fd, nlh0, AF_UNIX,
 		       SOCK_DIAG_BY_FAMILY, NLM_F_REQUEST, req,
 		       printf("{sdiag_family=AF_UNIX"),
@@ -245,7 +245,6 @@ test_unix_diag_req(const int fd)
 static void
 test_unix_diag_msg(const int fd)
 {
-	void *const nlh0 = tail_alloc(NLMSG_HDRLEN);
 	static const struct unix_diag_msg msg = {
 		.udiag_family = AF_UNIX,
 		.udiag_type = SOCK_STREAM,
@@ -253,6 +252,7 @@ test_unix_diag_msg(const int fd)
 		.udiag_ino = 0xfacefeed,
 		.udiag_cookie = { 0xdeadbeef, 0xbadc0ded }
 	};
+	void *const nlh0 = midtail_alloc(NLMSG_HDRLEN, sizeof(msg));
 	TEST_SOCK_DIAG(fd, nlh0, AF_UNIX,
 		       SOCK_DIAG_BY_FAMILY, NLM_F_DUMP, msg,
 		       printf("{udiag_family=AF_UNIX"),
@@ -266,7 +266,6 @@ test_unix_diag_msg(const int fd)
 static void
 test_netlink_diag_req(const int fd)
 {
-	void *const nlh0 = tail_alloc(NLMSG_HDRLEN);
 	struct netlink_diag_req req = {
 		.sdiag_family = AF_NETLINK,
 		.sdiag_protocol = NDIAG_PROTO_ALL,
@@ -274,6 +273,7 @@ test_netlink_diag_req(const int fd)
 		.ndiag_show = NDIAG_SHOW_MEMINFO,
 		.ndiag_cookie = { 0xdeadbeef, 0xbadc0ded }
 	};
+	void *const nlh0 = midtail_alloc(NLMSG_HDRLEN, sizeof(req));
 	TEST_SOCK_DIAG(fd, nlh0, AF_NETLINK,
 		       SOCK_DIAG_BY_FAMILY, NLM_F_REQUEST, req,
 		       printf("{sdiag_family=AF_NETLINK"),
@@ -298,7 +298,6 @@ test_netlink_diag_req(const int fd)
 static void
 test_netlink_diag_msg(const int fd)
 {
-	void *const nlh0 = tail_alloc(NLMSG_HDRLEN);
 	static const struct netlink_diag_msg msg = {
 		.ndiag_family = AF_NETLINK,
 		.ndiag_type = SOCK_RAW,
@@ -310,6 +309,7 @@ test_netlink_diag_msg(const int fd)
 		.ndiag_ino = 0xdaeefacd,
 		.ndiag_cookie = { 0xbadc0ded, 0xdeadbeef }
 	};
+	void *const nlh0 = midtail_alloc(NLMSG_HDRLEN, sizeof(msg));
 	TEST_SOCK_DIAG(fd, nlh0, AF_NETLINK,
 		       SOCK_DIAG_BY_FAMILY, NLM_F_DUMP, msg,
 		       printf("{ndiag_family=AF_NETLINK"),
@@ -327,7 +327,6 @@ test_netlink_diag_msg(const int fd)
 static void
 test_packet_diag_req(const int fd)
 {
-	void *const nlh0 = tail_alloc(NLMSG_HDRLEN);
 	static const struct packet_diag_req req = {
 		.sdiag_family = AF_PACKET,
 		.sdiag_protocol = ETH_P_LOOP,
@@ -335,6 +334,7 @@ test_packet_diag_req(const int fd)
 		.pdiag_show = PACKET_SHOW_INFO,
 		.pdiag_cookie = { 0xdeadbeef, 0xbadc0ded }
 	};
+	void *const nlh0 = midtail_alloc(NLMSG_HDRLEN, sizeof(req));
 	TEST_SOCK_DIAG(fd, nlh0, AF_PACKET,
 		       SOCK_DIAG_BY_FAMILY, NLM_F_REQUEST, req,
 		       printf("{sdiag_family=AF_PACKET"),
@@ -348,7 +348,6 @@ test_packet_diag_req(const int fd)
 static void
 test_packet_diag_msg(const int fd)
 {
-	void *const nlh0 = tail_alloc(NLMSG_HDRLEN);
 	static const struct packet_diag_msg msg = {
 		.pdiag_family = AF_PACKET,
 		.pdiag_type = SOCK_STREAM,
@@ -356,6 +355,7 @@ test_packet_diag_msg(const int fd)
 		.pdiag_ino = 0xfacefeed,
 		.pdiag_cookie = { 0xdeadbeef, 0xbadc0ded }
 	};
+	void *const nlh0 = midtail_alloc(NLMSG_HDRLEN, sizeof(msg));
 	TEST_SOCK_DIAG(fd, nlh0, AF_PACKET,
 		       SOCK_DIAG_BY_FAMILY, NLM_F_DUMP, msg,
 		       printf("{pdiag_family=AF_PACKET"),
@@ -371,7 +371,6 @@ test_inet_diag_sockid(const int fd)
 {
 	const char address[] = "12.34.56.78";
 	const char address6[] = "12:34:56:78:90:ab:cd:ef";
-	void *const nlh0 = tail_alloc(NLMSG_HDRLEN);
 	struct inet_diag_req_v2 req = {
 		.sdiag_family = AF_INET,
 		.idiag_ext = 1 << (INET_DIAG_CONG - 1),
@@ -384,6 +383,7 @@ test_inet_diag_sockid(const int fd)
 			.idiag_cookie = { 0xdeadbeef, 0xbadc0ded }
 		},
 	};
+	void *const nlh0 = midtail_alloc(NLMSG_HDRLEN, sizeof(req));
 
 	if (!inet_pton(AF_INET, address, &req.id.idiag_src) ||
 	    !inet_pton(AF_INET, address, &req.id.idiag_dst))
@@ -435,7 +435,6 @@ static void
 test_inet_diag_req(const int fd)
 {
 	const char address[] = "12.34.56.78";
-	void *const nlh0 = tail_alloc(NLMSG_HDRLEN);
 	struct inet_diag_req req = {
 		.idiag_family = AF_INET,
 		.idiag_src_len = 0xde,
@@ -450,6 +449,7 @@ test_inet_diag_req(const int fd)
 		.idiag_states = 1 << TCP_LAST_ACK,
 		.idiag_dbs = 0xfacefeed,
 	};
+	void *const nlh0 = midtail_alloc(NLMSG_HDRLEN, sizeof(req));
 
 	if (!inet_pton(AF_INET, address, &req.id.idiag_src) ||
 	    !inet_pton(AF_INET, address, &req.id.idiag_dst))
@@ -479,7 +479,6 @@ static void
 test_inet_diag_req_v2(const int fd)
 {
 	const char address[] = "87.65.43.21";
-	void *const nlh0 = tail_alloc(NLMSG_HDRLEN);
 	struct inet_diag_req_v2 req = {
 		.sdiag_family = AF_INET,
 		.idiag_ext = 1 << (INET_DIAG_CONG - 1),
@@ -492,6 +491,7 @@ test_inet_diag_req_v2(const int fd)
 			.idiag_cookie = { 0xdeadbeef, 0xbadc0ded }
 		},
 	};
+	void *const nlh0 = midtail_alloc(NLMSG_HDRLEN, sizeof(req));
 
 	if (!inet_pton(AF_INET, address, &req.id.idiag_src) ||
 	    !inet_pton(AF_INET, address, &req.id.idiag_dst))
@@ -519,7 +519,6 @@ static void
 test_inet_diag_msg(const int fd)
 {
 	const char address[] = "11.22.33.44";
-	void *const nlh0 = tail_alloc(NLMSG_HDRLEN);
 	struct inet_diag_msg msg = {
 		.idiag_family = AF_INET,
 		.idiag_state = TCP_LISTEN,
@@ -537,6 +536,7 @@ test_inet_diag_msg(const int fd)
 		.idiag_uid = 0xdecefaeb,
 		.idiag_inode = 0xbadc0ded,
 	};
+	void *const nlh0 = midtail_alloc(NLMSG_HDRLEN, sizeof(msg));
 
 	if (!inet_pton(AF_INET, address, &msg.id.idiag_src) ||
 	    !inet_pton(AF_INET, address, &msg.id.idiag_dst))
@@ -570,7 +570,6 @@ static void
 test_smc_diag_req(const int fd)
 {
 	const char address[] = "43.21.56.78";
-	void *const nlh0 = tail_alloc(NLMSG_HDRLEN);
 	struct smc_diag_req req = {
 		.diag_family = AF_SMC,
 		.diag_ext = 1 << (SMC_DIAG_CONNINFO - 1),
@@ -581,6 +580,7 @@ test_smc_diag_req(const int fd)
 			.idiag_cookie = { 0xdeadbeef, 0xbadc0ded },
 		},
 	};
+	void *const nlh0 = midtail_alloc(NLMSG_HDRLEN, sizeof(req));
 
 	if (!inet_pton(AF_INET, address, &req.id.idiag_src) ||
 	    !inet_pton(AF_INET, address, &req.id.idiag_dst))
@@ -606,7 +606,6 @@ static void
 test_smc_diag_msg(const int fd)
 {
 	const char address[] = "34.87.12.90";
-	void *const nlh0 = tail_alloc(NLMSG_HDRLEN);
 	struct smc_diag_msg msg = {
 		.diag_family = AF_SMC,
 		.diag_state = SMC_ACTIVE,
@@ -621,6 +620,7 @@ test_smc_diag_msg(const int fd)
 		.diag_uid = 0xadcdfafc,
 		.diag_inode = 0xbadc0ded,
 	};
+	void *const nlh0 = midtail_alloc(NLMSG_HDRLEN, sizeof(msg));
 
 	if (!inet_pton(AF_INET, address, &msg.id.idiag_src) ||
 	    !inet_pton(AF_INET, address, &msg.id.idiag_dst))