diff options
| -rw-r--r-- | tools/testing/selftests/mm/memfd_secret.c | 51 |
1 files changed, 49 insertions, 2 deletions
diff --git a/tools/testing/selftests/mm/memfd_secret.c b/tools/testing/selftests/mm/memfd_secret.c index 9b298f6a04b3..9a0597310a76 100644 --- a/tools/testing/selftests/mm/memfd_secret.c +++ b/tools/testing/selftests/mm/memfd_secret.c @@ -20,6 +20,7 @@ #include <unistd.h> #include <errno.h> #include <stdio.h> +#include <fcntl.h> #include "../kselftest.h" @@ -83,6 +84,45 @@ static void test_mlock_limit(int fd) pass("mlock limit is respected\n"); } +static void test_vmsplice(int fd, const char *desc) +{ + ssize_t transferred; + struct iovec iov; + int pipefd[2]; + char *mem; + + if (pipe(pipefd)) { + fail("pipe failed: %s\n", strerror(errno)); + return; + } + + mem = mmap(NULL, page_size, prot, mode, fd, 0); + if (mem == MAP_FAILED) { + fail("Unable to mmap secret memory\n"); + goto close_pipe; + } + + /* + * vmsplice() may use GUP-fast, which must also fail. Prefault the + * page table, so GUP-fast could find it. + */ + memset(mem, PATTERN, page_size); + + iov.iov_base = mem; + iov.iov_len = page_size; + transferred = vmsplice(pipefd[1], &iov, 1, 0); + + if (transferred < 0 && errno == EFAULT) + pass("vmsplice is blocked as expected with %s\n", desc); + else + fail("vmsplice: unexpected memory access with %s\n", desc); + + munmap(mem, page_size); +close_pipe: + close(pipefd[0]); + close(pipefd[1]); +} + static void try_process_vm_read(int fd, int pipefd[2]) { struct iovec liov, riov; @@ -187,7 +227,6 @@ static void test_remote_access(int fd, const char *name, return; } - ftruncate(fd, page_size); memset(mem, PATTERN, page_size); if (write(pipefd[1], &mem, sizeof(mem)) < 0) { @@ -258,7 +297,7 @@ static void prepare(void) strerror(errno)); } -#define NUM_TESTS 4 +#define NUM_TESTS 6 int main(int argc, char *argv[]) { @@ -277,9 +316,17 @@ int main(int argc, char *argv[]) ksft_exit_fail_msg("memfd_secret failed: %s\n", strerror(errno)); } + if (ftruncate(fd, page_size)) + ksft_exit_fail_msg("ftruncate failed: %s\n", strerror(errno)); test_mlock_limit(fd); test_file_apis(fd); + /* + * We have to run the first vmsplice test before any secretmem page was + * allocated for this fd. + */ + test_vmsplice(fd, "fresh page"); + test_vmsplice(fd, "existing page"); test_process_vm_read(fd); test_ptrace(fd); |