From: Michal Luczaj <mhal@rbox.co>
Date: Tue, 7 Jul 2026 04:23:59 +0000 (+0200)
Subject: selftests/bpf: Fail unbound UDP on sockmap update
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=203b06932777b9ad5085319389dea566f5c2ca63;p=thirdparty%2Fkernel%2Flinux.git

selftests/bpf: Fail unbound UDP on sockmap update

sockmap now rejects unbound UDP sockets. Adjust test_maps. While at it,
check socket()'s return value.

This effectively reverts commit c39aa2159974 ("bpf, selftests: Fix
test_maps now that sockmap supports UDP").

Signed-off-by: Michal Luczaj <mhal@rbox.co>
Reviewed-by: Kuniyuki Iwashima <kuniyu@google.com>
Reviewed-by: Jakub Sitnicki <jakub@cloudflare.com>
Link: https://lore.kernel.org/bpf/20260707-sockmap-lookup-udp-leak-v4-4-f878346f27ab@rbox.co
Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
---

diff --git a/tools/testing/selftests/bpf/test_maps.c b/tools/testing/selftests/bpf/test_maps.c
index c32da7bd8be2..6a2641ee7897 100644
--- a/tools/testing/selftests/bpf/test_maps.c
+++ b/tools/testing/selftests/bpf/test_maps.c
@@ -759,16 +759,15 @@ static void test_sockmap(unsigned int tasks, void *data)
 		goto out_sockmap;
 	}
 
-	/* Test update with unsupported UDP socket */
+	/* Test update with unsupported unbound UDP socket */
 	udp = socket(AF_INET, SOCK_DGRAM, 0);
-	i = 0;
-	err = bpf_map_update_elem(fd, &i, &udp, BPF_ANY);
-	if (err) {
-		printf("Failed socket update SOCK_DGRAM '%i:%i'\n",
-		       i, udp);
+	CHECK(udp < 0, "socket(AF_INET, SOCK_DGRAM)", "errno:%d\n", errno);
+	err = bpf_map_update_elem(fd, &(int){0}, &udp, BPF_ANY);
+	close(udp);
+	if (!err) {
+		printf("Unexpectedly succeeded unbound UDP update '0:%i'\n", udp);
 		goto out_sockmap;
 	}
-	close(udp);
 
 	/* Test update without programs */
 	for (i = 0; i < 6; i++) {