diff mbox series

[net,v2,2/2] selftests: net: test extacks in netlink dumps

Message ID 20241119224432.1713040-2-kuba@kernel.org (mailing list archive)
State New
Delegated to: Netdev Maintainers
Headers show
Series [net,v2,1/2] netlink: fix false positive warning in extack during dumps | expand

Checks

Context Check Description
netdev/series_format success Single patches do not need cover letters
netdev/tree_selection success Clearly marked for net, async
netdev/ynl success Generated files up to date; no warnings/errors; no diff in generated;
netdev/fixes_present success Fixes tag present in non-next series
netdev/header_inline success No static functions without inline keyword in header files
netdev/build_32bit success Errors and warnings before: 3 this patch: 3
netdev/build_tools success Errors and warnings before: 0 (+0) this patch: 0 (+0)
netdev/cc_maintainers warning 1 maintainers not CCed: shuah@kernel.org
netdev/build_clang success Errors and warnings before: 4 this patch: 4
netdev/verify_signedoff success Signed-off-by tag matches author and committer
netdev/deprecated_api success None detected
netdev/check_selftest success No net selftest shell script
netdev/verify_fixes success No Fixes tag
netdev/build_allmodconfig_warn success Errors and warnings before: 8 this patch: 8
netdev/checkpatch success total: 0 errors, 0 warnings, 0 checks, 155 lines checked
netdev/build_clang_rust success No Rust files in patch. Skipping build
netdev/kdoc success Errors and warnings before: 0 this patch: 0
netdev/source_inline success Was 0 now: 0

Commit Message

Jakub Kicinski Nov. 19, 2024, 10:44 p.m. UTC
Test that extacks in dumps work. The test fills up the receive buffer
to test both the inline dump (as part of sendmsg()) and delayed one
(run during recvmsg()).

Use YNL helpers to parse the messages. We need to add the test to YNL
file to make sure the right include path are used.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
---
CC: linux-kselftest@vger.kernel.org
---
 tools/testing/selftests/net/Makefile        |   3 +-
 tools/testing/selftests/net/netlink-dumps.c | 129 ++++++++++++++++++++
 2 files changed, 130 insertions(+), 2 deletions(-)
diff mbox series

Patch

diff --git a/tools/testing/selftests/net/Makefile b/tools/testing/selftests/net/Makefile
index 5e86f7a51b43..c427ee32b193 100644
--- a/tools/testing/selftests/net/Makefile
+++ b/tools/testing/selftests/net/Makefile
@@ -78,7 +78,6 @@  TEST_PROGS += test_vxlan_vnifiltering.sh
 TEST_GEN_FILES += io_uring_zerocopy_tx
 TEST_PROGS += io_uring_zerocopy_tx.sh
 TEST_GEN_FILES += bind_bhash
-TEST_GEN_PROGS += netlink-dumps
 TEST_GEN_PROGS += sk_bind_sendto_listen
 TEST_GEN_PROGS += sk_connect_zero_addr
 TEST_GEN_PROGS += sk_so_peek_off
@@ -100,7 +99,7 @@  TEST_PROGS += bpf_offload.py
 
 # YNL files, must be before "include ..lib.mk"
 EXTRA_CLEAN += $(OUTPUT)/libynl.a
-YNL_GEN_FILES := ncdevmem
+YNL_GEN_FILES := ncdevmem netlink-dumps
 TEST_GEN_FILES += $(YNL_GEN_FILES)
 
 TEST_FILES := settings
diff --git a/tools/testing/selftests/net/netlink-dumps.c b/tools/testing/selftests/net/netlink-dumps.c
index 7ee6dcd334df..195febbf6a61 100644
--- a/tools/testing/selftests/net/netlink-dumps.c
+++ b/tools/testing/selftests/net/netlink-dumps.c
@@ -12,11 +12,140 @@ 
 #include <unistd.h>
 
 #include <linux/genetlink.h>
+#include <linux/neighbour.h>
+#include <linux/netdevice.h>
 #include <linux/netlink.h>
 #include <linux/mqueue.h>
+#include <linux/rtnetlink.h>
 
 #include "../kselftest_harness.h"
 
+#include <ynl.h>
+
+struct ext_ack {
+	int err;
+
+	__u32 attr_offs;
+	__u32 miss_type;
+	__u32 miss_nest;
+	const char *str;
+};
+
+/* 0: no done, 1: done found, 2: extack found, -1: error */
+static int nl_get_extack(char *buf, size_t n, struct ext_ack *ea)
+{
+	const struct nlmsghdr *nlh;
+	const struct nlattr *attr;
+	ssize_t rem;
+
+	for (rem = n; rem > 0; NLMSG_NEXT(nlh, rem)) {
+		nlh = (struct nlmsghdr *)&buf[n - rem];
+		if (!NLMSG_OK(nlh, rem))
+			return -1;
+
+		if (nlh->nlmsg_type != NLMSG_DONE)
+			continue;
+
+		ea->err = -*(int *)NLMSG_DATA(nlh);
+
+		if (!(nlh->nlmsg_flags & NLM_F_ACK_TLVS))
+			return 1;
+
+		ynl_attr_for_each(attr, nlh, sizeof(int)) {
+			switch (ynl_attr_type(attr)) {
+			case NLMSGERR_ATTR_OFFS:
+				ea->attr_offs = ynl_attr_get_u32(attr);
+				break;
+			case NLMSGERR_ATTR_MISS_TYPE:
+				ea->miss_type = ynl_attr_get_u32(attr);
+				break;
+			case NLMSGERR_ATTR_MISS_NEST:
+				ea->miss_nest = ynl_attr_get_u32(attr);
+				break;
+			case NLMSGERR_ATTR_MSG:
+				ea->str = ynl_attr_get_str(attr);
+				break;
+			}
+		}
+
+		return 2;
+	}
+
+	return 0;
+}
+
+static const struct {
+	struct nlmsghdr nlhdr;
+	struct ndmsg ndm;
+	struct nlattr ahdr;
+	__u32 val;
+} dump_neigh_bad = {
+	.nlhdr = {
+		.nlmsg_len	= sizeof(dump_neigh_bad),
+		.nlmsg_type	= RTM_GETNEIGH,
+		.nlmsg_flags	= NLM_F_REQUEST | NLM_F_ACK | NLM_F_DUMP,
+		.nlmsg_seq	= 1,
+	},
+	.ndm = {
+		.ndm_family	= 123,
+	},
+	.ahdr = {
+		.nla_len	= 4 + 4,
+		.nla_type	= NDA_FLAGS_EXT,
+	},
+	.val = -1, // should fail MASK validation
+};
+
+TEST(dump_extack)
+{
+	int netlink_sock;
+	char buf[8192];
+	int one = 1;
+	int i, cnt;
+	ssize_t n;
+
+	netlink_sock = socket(AF_NETLINK, SOCK_RAW, NETLINK_ROUTE);
+	ASSERT_GE(netlink_sock, 0);
+
+	n = setsockopt(netlink_sock, SOL_NETLINK, NETLINK_CAP_ACK,
+		       &one, sizeof(one));
+	ASSERT_EQ(n, 0);
+	n = setsockopt(netlink_sock, SOL_NETLINK, NETLINK_EXT_ACK,
+		       &one, sizeof(one));
+	ASSERT_EQ(n, 0);
+	n = setsockopt(netlink_sock, SOL_NETLINK, NETLINK_GET_STRICT_CHK,
+		       &one, sizeof(one));
+	ASSERT_EQ(n, 0);
+
+	/* Dump so many times we fill up the buffer */
+	cnt = 64;
+	for (i = 0; i < cnt; i++) {
+		n = send(netlink_sock, &dump_neigh_bad,
+			 sizeof(dump_neigh_bad), 0);
+		ASSERT_EQ(n, sizeof(dump_neigh_bad));
+	}
+
+	/* Read out the ENOBUFS */
+	n = recv(netlink_sock, buf, sizeof(buf), MSG_DONTWAIT);
+	EXPECT_EQ(n, -1);
+	EXPECT_EQ(errno, ENOBUFS);
+
+	for (i = 0; i < cnt; i++) {
+		struct ext_ack ea = {};
+
+		n = recv(netlink_sock, buf, sizeof(buf), MSG_DONTWAIT);
+		if (n < 0) {
+			ASSERT_GE(i, 10);
+			break;
+		}
+		ASSERT_GE(n, (ssize_t)sizeof(struct nlmsghdr));
+
+		EXPECT_EQ(nl_get_extack(buf, n, &ea), 2);
+		EXPECT_EQ(ea.attr_offs,
+			  sizeof(struct nlmsghdr) + sizeof(struct ndmsg));
+	}
+}
+
 static const struct {
 	struct nlmsghdr nlhdr;
 	struct genlmsghdr genlhdr;