Add a kselftest that exercises the RDS getsockopt() paths converted to the getsockopt_iter() / sockopt_t callback:
- RDS_RECVERR and SO_RDS_TRANSPORT, which return their int value through copy_to_iter() and report the written length in opt->optlen. - RDS_INFO_*, which obtains the userspace buffer pages with iov_iter_extract_pages() (including a non-zero starting page offset) and lets the info producers copy the snapshot in under a spinlock. Signed-off-by: Breno Leitao <[email protected]> --- tools/testing/selftests/net/rds/.gitignore | 1 + tools/testing/selftests/net/rds/Makefile | 4 + tools/testing/selftests/net/rds/getsockopt.c | 201 +++++++++++++++++++++++++++ 3 files changed, 206 insertions(+) diff --git a/tools/testing/selftests/net/rds/.gitignore b/tools/testing/selftests/net/rds/.gitignore index 1c6f04e2aa11..7ca4b1440f51 100644 --- a/tools/testing/selftests/net/rds/.gitignore +++ b/tools/testing/selftests/net/rds/.gitignore @@ -1 +1,2 @@ include.sh +getsockopt diff --git a/tools/testing/selftests/net/rds/Makefile b/tools/testing/selftests/net/rds/Makefile index fe363be8e358..0700d8298eec 100644 --- a/tools/testing/selftests/net/rds/Makefile +++ b/tools/testing/selftests/net/rds/Makefile @@ -5,6 +5,8 @@ all: TEST_PROGS := run.sh +TEST_GEN_PROGS := getsockopt + TEST_FILES := \ include.sh \ settings \ @@ -16,4 +18,6 @@ EXTRA_CLEAN := \ /tmp/rds_logs \ # end of EXTRA_CLEAN +CFLAGS += $(KHDR_INCLUDES) + include ../../lib.mk diff --git a/tools/testing/selftests/net/rds/getsockopt.c b/tools/testing/selftests/net/rds/getsockopt.c new file mode 100644 index 000000000000..a82ffe4871c2 --- /dev/null +++ b/tools/testing/selftests/net/rds/getsockopt.c @@ -0,0 +1,201 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Exercise the RDS getsockopt() paths that were converted to the + * getsockopt_iter() / sockopt_t callback. + * + * Three distinct paths are covered: + * + * - RDS_RECVERR and SO_RDS_TRANSPORT, which now return their int value + * through copy_to_iter() and report the written length in opt->optlen. + * + * - RDS_INFO_*, which pins the userspace buffer with + * iov_iter_extract_pages() (including a non-zero starting page offset) + * and lets the info producers memcpy the snapshot in under a spinlock. + * + * The kvec (in-kernel buffer) -> -EOPNOTSUPP path of rds_info_getsockopt() + * is not reachable from a userspace getsockopt() and so is not tested here. + */ +#include <errno.h> +#include <stdint.h> +#include <string.h> +#include <unistd.h> +#include <sys/mman.h> +#include <sys/socket.h> +#include <linux/rds.h> + +#include "../../kselftest_harness.h" + +#ifndef AF_RDS +#define AF_RDS 21 +#endif + +FIXTURE(rds) { + int fd; +}; + +FIXTURE_SETUP(rds) +{ + self->fd = socket(AF_RDS, SOCK_SEQPACKET, 0); + if (self->fd < 0) + SKIP(return, "AF_RDS unavailable (errno %d) - load the rds module", + errno); +} + +FIXTURE_TEARDOWN(rds) +{ + if (self->fd >= 0) + close(self->fd); +} + +/* RDS_RECVERR defaults to 0 and is reported back as a 4-byte int. */ +TEST_F(rds, recverr_default) +{ + socklen_t len = sizeof(int); + int val = 0xdeadbeef; + + ASSERT_EQ(0, getsockopt(self->fd, SOL_RDS, RDS_RECVERR, &val, &len)); + EXPECT_EQ(sizeof(int), len); + EXPECT_EQ(0, val); +} + +/* A value set via setsockopt() must be readable back unchanged. */ +TEST_F(rds, recverr_set_get) +{ + socklen_t len = sizeof(int); + int val = 1; + + ASSERT_EQ(0, setsockopt(self->fd, SOL_RDS, RDS_RECVERR, &val, len)); + + val = 0; + ASSERT_EQ(0, getsockopt(self->fd, SOL_RDS, RDS_RECVERR, &val, &len)); + EXPECT_EQ(sizeof(int), len); + EXPECT_EQ(1, val); +} + +/* A buffer smaller than an int is rejected with EINVAL, not silently. */ +TEST_F(rds, recverr_short_buffer) +{ + socklen_t len = sizeof(int) - 1; + char buf[sizeof(int)]; + + EXPECT_EQ(-1, getsockopt(self->fd, SOL_RDS, RDS_RECVERR, buf, &len)); + EXPECT_EQ(EINVAL, errno); +} + +/* An unbound socket reports RDS_TRANS_NONE for SO_RDS_TRANSPORT. */ +TEST_F(rds, transport_unbound) +{ + socklen_t len = sizeof(int); + int val = 0; + + ASSERT_EQ(0, getsockopt(self->fd, SOL_RDS, SO_RDS_TRANSPORT, &val, + &len)); + EXPECT_EQ(sizeof(int), len); + EXPECT_EQ(RDS_TRANS_NONE, (unsigned int)val); +} + +TEST_F(rds, transport_short_buffer) +{ + socklen_t len = sizeof(int) - 1; + char buf[sizeof(int)]; + + EXPECT_EQ(-1, getsockopt(self->fd, SOL_RDS, SO_RDS_TRANSPORT, buf, + &len)); + EXPECT_EQ(EINVAL, errno); +} + +/* + * RDS_INFO_COUNTERS with a zero-length buffer is the "probe" call: it must + * fail with ENOSPC and report the required snapshot size in optlen. + */ +TEST_F(rds, info_counters_probe) +{ + socklen_t len = 0; + + EXPECT_EQ(-1, getsockopt(self->fd, SOL_RDS, RDS_INFO_COUNTERS, NULL, + &len)); + EXPECT_EQ(ENOSPC, errno); + EXPECT_GT(len, 0); + /* The snapshot is an array of fixed-size counter records. */ + EXPECT_EQ(0, len % (socklen_t)sizeof(struct rds_info_counter)); +} + +/* + * A real snapshot into an unaligned userspace buffer exercises the + * iov_iter_extract_pages() path, including the non-zero offset0 handling + * that the patch reworked. Place the buffer at a non-page-aligned address + * spanning into the next page to make sure multi-page pinning works too. + */ +TEST_F(rds, info_counters_snapshot) +{ + struct rds_info_counter *ctr; + socklen_t need = 0, len; + long pagesz = sysconf(_SC_PAGESIZE); + unsigned int i, n; + char *region, *buf; + int ret; + + /* Probe for the required size. */ + getsockopt(self->fd, SOL_RDS, RDS_INFO_COUNTERS, NULL, &need); + ASSERT_GT(need, 0); + + region = mmap(NULL, 2 * pagesz, PROT_READ | PROT_WRITE, + MAP_PRIVATE | MAP_ANONYMOUS, -1, 0); + ASSERT_NE(MAP_FAILED, region); + + /* Unaligned start that runs past the first page boundary. */ + buf = region + pagesz - 64; + ASSERT_LE(need, (socklen_t)(pagesz + 64)); + + /* + * On success the RDS_INFO path returns the positive per-element size + * (lens.each) rather than 0, and writes the full snapshot length back + * into optlen. + */ + len = need; + ret = getsockopt(self->fd, SOL_RDS, RDS_INFO_COUNTERS, buf, &len); + ASSERT_GE(ret, 0) { + TH_LOG("getsockopt snapshot failed: errno %d", errno); + } + EXPECT_EQ(sizeof(struct rds_info_counter), ret); + EXPECT_EQ(need, len); + + /* The counter names must be NUL-terminated, non-empty strings. */ + ctr = (struct rds_info_counter *)buf; + n = len / sizeof(*ctr); + ASSERT_GT(n, 0); + for (i = 0; i < n; i++) { + size_t namelen = strnlen((char *)ctr[i].name, + sizeof(ctr[i].name)); + + EXPECT_GT(namelen, 0); + EXPECT_LT(namelen, sizeof(ctr[i].name)); + } + + munmap(region, 2 * pagesz); +} + +/* + * A non-zero but too-small buffer must report ENOSPC and the full required + * length, without corrupting memory past the buffer. + */ +TEST_F(rds, info_counters_short_buffer) +{ + socklen_t need = 0, len; + char small[sizeof(struct rds_info_counter)]; + + getsockopt(self->fd, SOL_RDS, RDS_INFO_COUNTERS, NULL, &need); + ASSERT_GT(need, 0); + + /* Ask with a buffer guaranteed smaller than the full snapshot. */ + if (need <= (socklen_t)sizeof(small)) + SKIP(return, "snapshot fits in one record; nothing to test"); + + len = 1; /* < sizeof(struct rds_info_counter) */ + EXPECT_EQ(-1, getsockopt(self->fd, SOL_RDS, RDS_INFO_COUNTERS, small, + &len)); + EXPECT_EQ(ENOSPC, errno); + EXPECT_EQ(need, len); +} + +TEST_HARNESS_MAIN -- 2.54.0
