From: "Pratyush Yadav (Google)" <[email protected]> Add a selftest that makes sure the contents of a memfd are correctly preserved across a live update. In stage 1, create a memfd and fill it with random data, and preserve it. Save the random data to the file system. This will be used by stage 2 to verify the contents are correct.
In stage 2, retrieve the memfd and compare its contents with the contents saved on the file system. Signed-off-by: Pratyush Yadav <[email protected]> Signed-off-by: Pratyush Yadav (Google) <[email protected]> --- tools/testing/selftests/liveupdate/Makefile | 1 + .../testing/selftests/liveupdate/luo_memfd.c | 61 +++++++++++++++++++ 2 files changed, 62 insertions(+) diff --git a/tools/testing/selftests/liveupdate/Makefile b/tools/testing/selftests/liveupdate/Makefile index 051daae55eec..8e2eb6500c07 100644 --- a/tools/testing/selftests/liveupdate/Makefile +++ b/tools/testing/selftests/liveupdate/Makefile @@ -13,6 +13,7 @@ TEST_FILES += do_kexec.sh include ../lib.mk CFLAGS += $(KHDR_INCLUDES) +CFLAGS += -I$(top_srcdir)/tools/include CFLAGS += -Wall -O2 -Wno-unused-function CFLAGS += -MD diff --git a/tools/testing/selftests/liveupdate/luo_memfd.c b/tools/testing/selftests/liveupdate/luo_memfd.c index b779eee18387..52b5f6b16e19 100644 --- a/tools/testing/selftests/liveupdate/luo_memfd.c +++ b/tools/testing/selftests/liveupdate/luo_memfd.c @@ -3,6 +3,9 @@ /* * Copyright (c) 2026, Google LLC. * Pratyush Yadav (Google) <[email protected]> + * + * Copyright (C) 2025 Amazon.com Inc. or its affiliates. + * Pratyush Yadav <[email protected]> */ /* @@ -11,11 +14,14 @@ #include <errno.h> #include <fcntl.h> +#include <stdlib.h> #include <string.h> #include <sys/ioctl.h> +#include <sys/mman.h> #include <unistd.h> #include <linux/liveupdate.h> +#include <linux/sizes.h> #include "../kselftest.h" #include "../kselftest_harness.h" @@ -25,9 +31,64 @@ #define STATE_SESSION_NAME "luo-state" #define STATE_MEMFD_TOKEN 1 +#define MEMFD_DATA_SESSION_NAME "memfd_data_session" +#define MEMFD_DATA_TOKEN 1 +#define MEMFD_DATA_BUFFER_SIZE SZ_1M +#define RANDOM_DATA_FILE "luo_random_data.bin" + #define LIVEUPDATE_DEV "/dev/liveupdate" static int luo_fd = -1, stage; +/* + * Test that a memfd with its data is preserved across live update. + */ +TEST(memfd_data) +{ + int fd, session; + char *buffer; + struct liveupdate_session_preserve_fd preserve_arg = { .size = sizeof(preserve_arg) }; + struct liveupdate_session_retrieve_fd retrieve_arg = { .size = sizeof(retrieve_arg) }; + + buffer = malloc(MEMFD_DATA_BUFFER_SIZE); + ASSERT_NE(buffer, NULL); + + switch (stage) { + case 1: + session = luo_create_session(luo_fd, MEMFD_DATA_SESSION_NAME); + ASSERT_GE(session, 0); + + fd = create_random_memfd("memfd_data", buffer, MEMFD_DATA_BUFFER_SIZE); + ASSERT_GE(fd, 0); + + ASSERT_EQ(save_test_data(RANDOM_DATA_FILE, buffer, MEMFD_DATA_BUFFER_SIZE), 0); + + preserve_arg.fd = fd; + preserve_arg.token = MEMFD_DATA_TOKEN; + ASSERT_GE(ioctl(session, LIVEUPDATE_SESSION_PRESERVE_FD, &preserve_arg), 0); + + daemonize_and_wait(); + break; + case 2: + session = luo_retrieve_session(luo_fd, MEMFD_DATA_SESSION_NAME); + ASSERT_GE(session, 0); + + ASSERT_EQ(load_test_data(RANDOM_DATA_FILE, buffer, MEMFD_DATA_BUFFER_SIZE), 0); + + retrieve_arg.token = MEMFD_DATA_TOKEN; + ASSERT_GE(ioctl(session, LIVEUPDATE_SESSION_RETRIEVE_FD, &retrieve_arg), 0); + fd = retrieve_arg.fd; + ASSERT_GE(fd, 0); + + ASSERT_EQ(verify_fd_content(fd, buffer, MEMFD_DATA_BUFFER_SIZE), 0); + + ASSERT_EQ(luo_session_finish(session), 0); + break; + default: + TH_LOG("Unknown stage %d\n", stage); + ASSERT_FALSE(true); + } +} + int main(int argc, char *argv[]) { int session, expected_stage = 0; -- 2.53.0.473.g4a7958ca14-goog
