From: Jeff Xu jeffxu@chromium.org
Add code to detect if the vdso is memory sealed, skip the test if it is.
Signed-off-by: Jeff Xu jeffxu@chromium.org Reviewed-by: Kees Cook kees@kernel.org Reviewed-by: Lorenzo Stoakes lorenzo.stoakes@oracle.com Reviewed-by: Liam R. Howlett Liam.Howlett@oracle.com --- .../testing/selftests/x86/test_mremap_vdso.c | 43 +++++++++++++++++++ 1 file changed, 43 insertions(+)
diff --git a/tools/testing/selftests/x86/test_mremap_vdso.c b/tools/testing/selftests/x86/test_mremap_vdso.c index d53959e03593..94bee6e0c813 100644 --- a/tools/testing/selftests/x86/test_mremap_vdso.c +++ b/tools/testing/selftests/x86/test_mremap_vdso.c @@ -14,6 +14,7 @@ #include <errno.h> #include <unistd.h> #include <string.h> +#include <stdbool.h>
#include <sys/mman.h> #include <sys/auxv.h> @@ -55,13 +56,55 @@ static int try_to_remap(void *vdso_addr, unsigned long size)
}
+#define VDSO_NAME "[vdso]" +#define VMFLAGS "VmFlags:" +#define MSEAL_FLAGS "sl" +#define MAX_LINE_LEN 512 + +bool vdso_sealed(FILE *maps) +{ + char line[MAX_LINE_LEN]; + bool has_vdso = false; + + while (fgets(line, sizeof(line), maps)) { + if (strstr(line, VDSO_NAME)) + has_vdso = true; + + if (has_vdso && !strncmp(line, VMFLAGS, strlen(VMFLAGS))) { + if (strstr(line, MSEAL_FLAGS)) + return true; + + return false; + } + } + + return false; +} + int main(int argc, char **argv, char **envp) { pid_t child; + FILE *maps;
ksft_print_header(); ksft_set_plan(1);
+ maps = fopen("/proc/self/smaps", "r"); + if (!maps) { + ksft_test_result_skip( + "Could not open /proc/self/smaps, errno=%d\n", + errno); + + return 0; + } + + if (vdso_sealed(maps)) { + ksft_test_result_skip("vdso is sealed\n"); + return 0; + } + + fclose(maps); + child = fork(); if (child == -1) ksft_exit_fail_msg("failed to fork (%d): %m\n", errno);