Module Name: src
Committed By: pho
Date: Mon Apr 22 07:24:22 UTC 2024
Modified Files:
src/distrib/sets/lists/tests: mi
src/tests/kernel: Makefile
Added Files:
src/tests/kernel: t_signal_and_sp.c
src/tests/kernel/arch/aarch64: stack_pointer.h
Log Message:
Add a test for kern/58149
aarch64: Cannot return from a signal handler if SP was misaligned when the
signal arrived
To generate a diff of this commit:
cvs rdiff -u -r1.1311 -r1.1312 src/distrib/sets/lists/tests/mi
cvs rdiff -u -r1.77 -r1.78 src/tests/kernel/Makefile
cvs rdiff -u -r0 -r1.1 src/tests/kernel/t_signal_and_sp.c
cvs rdiff -u -r0 -r1.1 src/tests/kernel/arch/aarch64/stack_pointer.h
Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.
Modified files:
Index: src/distrib/sets/lists/tests/mi
diff -u src/distrib/sets/lists/tests/mi:1.1311 src/distrib/sets/lists/tests/mi:1.1312
--- src/distrib/sets/lists/tests/mi:1.1311 Fri Mar 15 15:32:07 2024
+++ src/distrib/sets/lists/tests/mi Mon Apr 22 07:24:22 2024
@@ -1,4 +1,4 @@
-# $NetBSD: mi,v 1.1311 2024/03/15 15:32:07 riastradh Exp $
+# $NetBSD: mi,v 1.1312 2024/04/22 07:24:22 pho Exp $
#
# Note: don't delete entries from here - mark them as "obsolete" instead.
#
@@ -2347,6 +2347,7 @@
./usr/tests/kernel/t_pty tests-kernel-tests compattestfile,atf
./usr/tests/kernel/t_rnd tests-kernel-tests atf,rump
./usr/tests/kernel/t_sigaction tests-obsolete obsolete
+./usr/tests/kernel/t_signal_and_sp tests-kernel-tests compattestfile,atf
./usr/tests/kernel/t_simplehook tests-kernel-tests atf,rump
./usr/tests/kernel/t_subr_prf tests-kernel-tests compattestfile,atf
./usr/tests/kernel/t_sysctl tests-kernel-tests compattestfile,atf
Index: src/tests/kernel/Makefile
diff -u src/tests/kernel/Makefile:1.77 src/tests/kernel/Makefile:1.78
--- src/tests/kernel/Makefile:1.77 Tue Oct 17 13:51:52 2023
+++ src/tests/kernel/Makefile Mon Apr 22 07:24:22 2024
@@ -1,4 +1,4 @@
-# $NetBSD: Makefile,v 1.77 2023/10/17 13:51:52 rjs Exp $
+# $NetBSD: Makefile,v 1.78 2024/04/22 07:24:22 pho Exp $
NOMAN= # defined
@@ -18,6 +18,7 @@ TESTS_C+= t_pty
TESTS_C+= t_memfd_create
TESTS_C+= t_mqueue
TESTS_C+= t_proccwd
+TESTS_C+= t_signal_and_sp
TESTS_C+= t_sysv
TESTS_C+= t_subr_prf
TESTS_C+= t_kauth_pr_47598
@@ -79,6 +80,11 @@ LDADD.t_timeleft+= -lpthread
CPPFLAGS+= -D_KERNTYPES
+ARCH_INCS_DIR:= ${.PARSEDIR}/arch/${MACHINE_ARCH}
+.if exists(${ARCH_INCS_DIR}/stack_pointer.h)
+CPPFLAGS+= -I${ARCH_INCS_DIR} -DHAVE_STACK_POINTER_H
+.endif
+
.PATH: ${NETBSDSRCDIR}/sys/kern
TESTS_C+= t_extent
SRCS.t_extent= t_extent.c subr_extent.c
Added files:
Index: src/tests/kernel/t_signal_and_sp.c
diff -u /dev/null src/tests/kernel/t_signal_and_sp.c:1.1
--- /dev/null Mon Apr 22 07:24:22 2024
+++ src/tests/kernel/t_signal_and_sp.c Mon Apr 22 07:24:22 2024
@@ -0,0 +1,117 @@
+/* $NetBSD: t_signal_and_sp.c,v 1.1 2024/04/22 07:24:22 pho Exp $ */
+
+/*
+ * Copyright (c) 2024 The NetBSD Foundation, Inc.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
+ * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
+ * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+ * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
+ * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include <atf-c.h>
+
+#if defined(HAVE_STACK_POINTER_H)
+# include <signal.h>
+# include <string.h>
+# include <sys/stdint.h>
+# include <sys/time.h>
+# include "stack_pointer.h"
+
+static volatile void* stack_pointer = NULL;
+static void on_alarm(int sig __attribute__((__unused__)))
+{
+ /*
+ * Store the stack pointer into a variable so that we can test if
+ * it's aligned.
+ */
+ LOAD_SP(stack_pointer);
+
+ /*
+ * Now we are going to return from a signal
+ * handler. __sigtramp_siginfo_2 will call setcontext(2) with a
+ * ucontext provided by the kernel. When that fails it will call
+ * _Exit(2) with the errno, and the test will fail.
+ */
+}
+#endif
+
+ATF_TC(misaligned_sp_and_signal);
+ATF_TC_HEAD(misaligned_sp_and_signal, tc)
+{
+ atf_tc_set_md_var(tc, "descr", "process can return from a signal"
+ " handler even if the stack pointer is misaligned when a signal"
+ " arrives");
+}
+ATF_TC_BODY(misaligned_sp_and_signal, tc)
+{
+#if defined(HAVE_STACK_POINTER_H)
+ /*
+ * Set up a handler for SIGALRM.
+ */
+ struct sigaction sa;
+ memset(&sa, 0, sizeof(sa));
+ sa.sa_handler = &on_alarm;
+ ATF_REQUIRE(sigaction(SIGALRM, &sa, NULL) == 0);
+
+ /*
+ * Set up an interval timer so that we receive SIGALRM after 50 ms.
+ */
+ struct itimerval itv;
+ memset(&itv, 0, sizeof(itv));
+ itv.it_value.tv_usec = 1000 * 50;
+ ATF_REQUIRE(setitimer(ITIMER_MONOTONIC, &itv, NULL) == 0);
+
+ /*
+ * Now misalign the SP. Wait for the signal to arrive and see what
+ * happens. This should be fine as long as we don't use it to
+ * access memory.
+ */
+ MISALIGN_SP;
+ while (stack_pointer == NULL) {
+ /*
+ * Make sure the compiler does not optimize this busy loop
+ * away.
+ */
+ __asm__("" : : : "memory");
+ }
+ /*
+ * We could successfully return from a signal handler. Now we
+ * should fix the SP before calling any functions.
+ */
+ FIX_SP;
+
+ /*
+ * But was the stack pointer aligned when we were on the signal
+ * handler?
+ */
+ ATF_CHECK_MSG(is_sp_aligned((uintptr_t)stack_pointer),
+ "signal handler was called with a misaligned sp: %p",
+ stack_pointer);
+#else
+ atf_tc_skip("Not implemented for this platform");
+#endif
+}
+
+ATF_TP_ADD_TCS(tp)
+{
+ ATF_TP_ADD_TC(tp, misaligned_sp_and_signal);
+ return atf_no_error();
+}
Index: src/tests/kernel/arch/aarch64/stack_pointer.h
diff -u /dev/null src/tests/kernel/arch/aarch64/stack_pointer.h:1.1
--- /dev/null Mon Apr 22 07:24:22 2024
+++ src/tests/kernel/arch/aarch64/stack_pointer.h Mon Apr 22 07:24:22 2024
@@ -0,0 +1,56 @@
+/* $NetBSD: stack_pointer.h,v 1.1 2024/04/22 07:24:22 pho Exp $ */
+
+/*
+ * Copyright (c) 2024 The NetBSD Foundation, Inc.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
+ * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
+ * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+ * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
+ * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include <sys/stdbool.h>
+#include <sys/stdint.h>
+
+#define LOAD_SP(var) \
+ do { \
+ register void* tmp __asm__("x0"); \
+ __asm__( \
+ "mov %0, sp" \
+ : "=r"(tmp) \
+ ); \
+ (var) = tmp; \
+ } while (0)
+
+#define MISALIGN_SP \
+ __asm__ volatile ( \
+ "sub sp, sp, #8" \
+ )
+
+#define FIX_SP \
+ __asm__ volatile ( \
+ "add sp, sp, #8" \
+ )
+
+static inline bool
+is_sp_aligned(uintptr_t sp)
+{
+ return sp % 16 == 0;
+}
