From 440c9d488705366b00372ea7213af69827a6c7af Mon Sep 17 00:00:00 2001 From: Michal Luczaj Date: Mon, 10 Feb 2025 13:15:01 +0100 Subject: [PATCH] vsock/test: Add test for SO_LINGER null ptr deref Explicitly close() a TCP_ESTABLISHED (connectible) socket with SO_LINGER enabled. As for now, test does not verify if close() actually lingers. On an unpatched machine, may trigger a null pointer dereference. Tested-by: Luigi Leonardi Reviewed-by: Luigi Leonardi Reviewed-by: Stefano Garzarella Signed-off-by: Michal Luczaj Link: https://patch.msgid.link/20250210-vsock-linger-nullderef-v3-2-ef6244d02b54@rbox.co Signed-off-by: Jakub Kicinski --- tools/testing/vsock/vsock_test.c | 41 ++++++++++++++++++++++++++++++++ 1 file changed, 41 insertions(+) diff --git a/tools/testing/vsock/vsock_test.c b/tools/testing/vsock/vsock_test.c index dfff8b288265f..d0f6d253ac72d 100644 --- a/tools/testing/vsock/vsock_test.c +++ b/tools/testing/vsock/vsock_test.c @@ -1788,6 +1788,42 @@ static void test_stream_connect_retry_server(const struct test_opts *opts) close(fd); } +static void test_stream_linger_client(const struct test_opts *opts) +{ + struct linger optval = { + .l_onoff = 1, + .l_linger = 1 + }; + int fd; + + fd = vsock_stream_connect(opts->peer_cid, opts->peer_port); + if (fd < 0) { + perror("connect"); + exit(EXIT_FAILURE); + } + + if (setsockopt(fd, SOL_SOCKET, SO_LINGER, &optval, sizeof(optval))) { + perror("setsockopt(SO_LINGER)"); + exit(EXIT_FAILURE); + } + + close(fd); +} + +static void test_stream_linger_server(const struct test_opts *opts) +{ + int fd; + + fd = vsock_stream_accept(VMADDR_CID_ANY, opts->peer_port, NULL); + if (fd < 0) { + perror("accept"); + exit(EXIT_FAILURE); + } + + vsock_wait_remote_close(fd); + close(fd); +} + static struct test_case test_cases[] = { { .name = "SOCK_STREAM connection reset", @@ -1943,6 +1979,11 @@ static struct test_case test_cases[] = { .run_client = test_stream_connect_retry_client, .run_server = test_stream_connect_retry_server, }, + { + .name = "SOCK_STREAM SO_LINGER null-ptr-deref", + .run_client = test_stream_linger_client, + .run_server = test_stream_linger_server, + }, {}, }; -- 2.49.0