From e1bb28bf13f41af5d7cc48359d1755cbcda4d502 Mon Sep 17 00:00:00 2001 From: Kuniyuki Iwashima Date: Mon, 17 Nov 2025 17:47:11 +0000 Subject: [PATCH] selftest: af_unix: Add test for SO_PEEK_OFF. The test covers various cases to verify SO_PEEK_OFF behaviour for all AF_UNIX socket types. two_chunks_blocking and two_chunks_overlap_blocking reproduce the issue mentioned in the previous patch. Without the patch, the two tests fail: # RUN so_peek_off.stream.two_chunks_blocking ... # so_peek_off.c:121:two_chunks_blocking:Expected 'bbbb' == 'aaaabbbb'. # two_chunks_blocking: Test terminated by assertion # FAIL so_peek_off.stream.two_chunks_blocking not ok 3 so_peek_off.stream.two_chunks_blocking # RUN so_peek_off.stream.two_chunks_overlap_blocking ... # so_peek_off.c:159:two_chunks_overlap_blocking:Expected 'bbbb' == 'aaaabbbb'. # two_chunks_overlap_blocking: Test terminated by assertion # FAIL so_peek_off.stream.two_chunks_overlap_blocking not ok 5 so_peek_off.stream.two_chunks_overlap_blocking With the patch, all tests pass: # PASSED: 15 / 15 tests passed. # Totals: pass:15 fail:0 xfail:0 xpass:0 skip:0 error:0 Signed-off-by: Kuniyuki Iwashima Link: https://patch.msgid.link/20251117174740.3684604-3-kuniyu@google.com Signed-off-by: Jakub Kicinski --- tools/testing/selftests/net/.gitignore | 1 + tools/testing/selftests/net/af_unix/Makefile | 1 + .../selftests/net/af_unix/so_peek_off.c | 162 ++++++++++++++++++ 3 files changed, 164 insertions(+) create mode 100644 tools/testing/selftests/net/af_unix/so_peek_off.c diff --git a/tools/testing/selftests/net/.gitignore b/tools/testing/selftests/net/.gitignore index 439101b518ee..8f9850a71f54 100644 --- a/tools/testing/selftests/net/.gitignore +++ b/tools/testing/selftests/net/.gitignore @@ -45,6 +45,7 @@ skf_net_off socket so_incoming_cpu so_netns_cookie +so_peek_off so_txtime so_rcv_listener stress_reuseport_listen diff --git a/tools/testing/selftests/net/af_unix/Makefile b/tools/testing/selftests/net/af_unix/Makefile index de805cbbdf69..528d14c598bb 100644 --- a/tools/testing/selftests/net/af_unix/Makefile +++ b/tools/testing/selftests/net/af_unix/Makefile @@ -6,6 +6,7 @@ TEST_GEN_PROGS := \ scm_inq \ scm_pidfd \ scm_rights \ + so_peek_off \ unix_connect \ # end of TEST_GEN_PROGS diff --git a/tools/testing/selftests/net/af_unix/so_peek_off.c b/tools/testing/selftests/net/af_unix/so_peek_off.c new file mode 100644 index 000000000000..1a77728128e5 --- /dev/null +++ b/tools/testing/selftests/net/af_unix/so_peek_off.c @@ -0,0 +1,162 @@ +// SPDX-License-Identifier: GPL-2.0 +/* Copyright 2025 Google LLC */ + +#include +#include + +#include + +#include "../../kselftest_harness.h" + +FIXTURE(so_peek_off) +{ + int fd[2]; /* 0: sender, 1: receiver */ +}; + +FIXTURE_VARIANT(so_peek_off) +{ + int type; +}; + +FIXTURE_VARIANT_ADD(so_peek_off, stream) +{ + .type = SOCK_STREAM, +}; + +FIXTURE_VARIANT_ADD(so_peek_off, dgram) +{ + .type = SOCK_DGRAM, +}; + +FIXTURE_VARIANT_ADD(so_peek_off, seqpacket) +{ + .type = SOCK_SEQPACKET, +}; + +FIXTURE_SETUP(so_peek_off) +{ + struct timeval timeout = { + .tv_sec = 0, + .tv_usec = 3000, + }; + int ret; + + ret = socketpair(AF_UNIX, variant->type, 0, self->fd); + ASSERT_EQ(0, ret); + + ret = setsockopt(self->fd[1], SOL_SOCKET, SO_RCVTIMEO_NEW, + &timeout, sizeof(timeout)); + ASSERT_EQ(0, ret); + + ret = setsockopt(self->fd[1], SOL_SOCKET, SO_PEEK_OFF, + &(int){0}, sizeof(int)); + ASSERT_EQ(0, ret); +} + +FIXTURE_TEARDOWN(so_peek_off) +{ + close_range(self->fd[0], self->fd[1], 0); +} + +#define sendeq(fd, str, flags) \ + do { \ + int bytes, len = strlen(str); \ + \ + bytes = send(fd, str, len, flags); \ + ASSERT_EQ(len, bytes); \ + } while (0) + +#define recveq(fd, str, buflen, flags) \ + do { \ + char buf[(buflen) + 1] = {}; \ + int bytes; \ + \ + bytes = recv(fd, buf, buflen, flags); \ + ASSERT_NE(-1, bytes); \ + ASSERT_STREQ(str, buf); \ + } while (0) + +#define async \ + for (pid_t pid = (pid = fork(), \ + pid < 0 ? \ + __TH_LOG("Failed to start async {}"), \ + _metadata->exit_code = KSFT_FAIL, \ + __bail(1, _metadata), \ + 0xdead : \ + pid); \ + !pid; exit(0)) + +TEST_F(so_peek_off, single_chunk) +{ + sendeq(self->fd[0], "aaaabbbb", 0); + + recveq(self->fd[1], "aaaa", 4, MSG_PEEK); + recveq(self->fd[1], "bbbb", 100, MSG_PEEK); +} + +TEST_F(so_peek_off, two_chunks) +{ + sendeq(self->fd[0], "aaaa", 0); + sendeq(self->fd[0], "bbbb", 0); + + recveq(self->fd[1], "aaaa", 4, MSG_PEEK); + recveq(self->fd[1], "bbbb", 100, MSG_PEEK); +} + +TEST_F(so_peek_off, two_chunks_blocking) +{ + async { + usleep(1000); + sendeq(self->fd[0], "aaaa", 0); + } + + recveq(self->fd[1], "aaaa", 4, MSG_PEEK); + + async { + usleep(1000); + sendeq(self->fd[0], "bbbb", 0); + } + + /* goto again; -> goto redo; in unix_stream_read_generic(). */ + recveq(self->fd[1], "bbbb", 100, MSG_PEEK); +} + +TEST_F(so_peek_off, two_chunks_overlap) +{ + sendeq(self->fd[0], "aaaa", 0); + recveq(self->fd[1], "aa", 2, MSG_PEEK); + + sendeq(self->fd[0], "bbbb", 0); + + if (variant->type == SOCK_STREAM) { + /* SOCK_STREAM tries to fill the buffer. */ + recveq(self->fd[1], "aabb", 4, MSG_PEEK); + recveq(self->fd[1], "bb", 100, MSG_PEEK); + } else { + /* SOCK_DGRAM and SOCK_SEQPACKET returns at the skb boundary. */ + recveq(self->fd[1], "aa", 100, MSG_PEEK); + recveq(self->fd[1], "bbbb", 100, MSG_PEEK); + } +} + +TEST_F(so_peek_off, two_chunks_overlap_blocking) +{ + async { + usleep(1000); + sendeq(self->fd[0], "aaaa", 0); + } + + recveq(self->fd[1], "aa", 2, MSG_PEEK); + + async { + usleep(1000); + sendeq(self->fd[0], "bbbb", 0); + } + + /* Even SOCK_STREAM does not wait if at least one byte is read. */ + recveq(self->fd[1], "aa", 100, MSG_PEEK); + + recveq(self->fd[1], "bbbb", 100, MSG_PEEK); +} + +TEST_HARNESS_MAIN -- 2.47.3