From e03e287aa2aad3ea993ed9513b6bb3f0bdf889a2 Mon Sep 17 00:00:00 2001 From: Brent Cook Date: Sat, 27 Mar 2021 11:17:59 +0000 Subject: Handle dynamic definition of SIGSTKSZ as of glibc 2.34 on Linux. ok bluhm@, inoguchi@, tb@, deraadt@ --- regress/lib/libc/explicit_bzero/explicit_bzero.c | 31 ++++++++++++++++++------ 1 file changed, 24 insertions(+), 7 deletions(-) (limited to 'regress/lib') diff --git a/regress/lib/libc/explicit_bzero/explicit_bzero.c b/regress/lib/libc/explicit_bzero/explicit_bzero.c index 34c60baa8a6..9c0e917829f 100644 --- a/regress/lib/libc/explicit_bzero/explicit_bzero.c +++ b/regress/lib/libc/explicit_bzero/explicit_bzero.c @@ -1,4 +1,4 @@ -/* $OpenBSD: explicit_bzero.c,v 1.6 2014/07/11 01:10:35 matthew Exp $ */ +/* $OpenBSD: explicit_bzero.c,v 1.7 2021/03/27 11:17:58 bcook Exp $ */ /* * Copyright (c) 2014 Google Inc. * @@ -18,6 +18,7 @@ #include #include #include +#include #include #include @@ -36,19 +37,33 @@ enum { SECRETBYTES = SECRETCOUNT * sizeof(secret) }; -static char altstack[SIGSTKSZ + SECRETBYTES]; +/* + * As of glibc 2.34, when _GNU_SOURCE is defined, SIGSTKSZ is no longer + * constant on Linux. SIGSTKSZ is redefined to sysconf (_SC_SIGSTKSZ). + */ +static char *altstack; +#define ALTSTACK_SIZE (SIGSTKSZ + SECRETBYTES) static void setup_stack(void) { + altstack = calloc(1, ALTSTACK_SIZE); + ASSERT_NE(NULL, altstack); + const stack_t sigstk = { .ss_sp = altstack, - .ss_size = sizeof(altstack), + .ss_size = ALTSTACK_SIZE }; ASSERT_EQ(0, sigaltstack(&sigstk, NULL)); } +static void +cleanup_stack(void) +{ + free(altstack); +} + static void assert_on_stack(void) { @@ -129,7 +144,7 @@ test_without_bzero() char buf[SECRETBYTES]; assert_on_stack(); populate_secret(buf, sizeof(buf)); - char *res = memmem(altstack, sizeof(altstack), buf, sizeof(buf)); + char *res = memmem(altstack, ALTSTACK_SIZE, buf, sizeof(buf)); ASSERT_NE(NULL, res); return (res); } @@ -140,7 +155,7 @@ test_with_bzero() char buf[SECRETBYTES]; assert_on_stack(); populate_secret(buf, sizeof(buf)); - char *res = memmem(altstack, sizeof(altstack), buf, sizeof(buf)); + char *res = memmem(altstack, ALTSTACK_SIZE, buf, sizeof(buf)); ASSERT_NE(NULL, res); explicit_bzero(buf, sizeof(buf)); return (res); @@ -183,15 +198,17 @@ main() * on the stack. This sanity checks that call_on_stack() and * populate_secret() work as intended. */ - memset(altstack, 0, sizeof(altstack)); + memset(altstack, 0, ALTSTACK_SIZE); call_on_stack(do_test_without_bzero); /* * Now test with a call to explicit_bzero() and check that we * *don't* find any instances of the secret data. */ - memset(altstack, 0, sizeof(altstack)); + memset(altstack, 0, ALTSTACK_SIZE); call_on_stack(do_test_with_bzero); + cleanup_stack(); + return (0); } -- cgit v1.2.3