Files
android/tools/testing/selftests/x86/vdso_restorer.c
T
threeeye bc1d038eac REVVL 6 Pro kernel bring-up: full working tree snapshot (2026-09-12)
Squashed backup commit (no shallow-clone history issues) of
xiaomi-mt6833-dev/kernel_xiaomi_mt6833 (lineage-23.2 branch, upstream
commit 9eece662e) plus all fixes applied to get everpal_defconfig building
clean against a modern (GCC 15.2.0) toolchain -- see the previous commit
message on the lineage-23.2 branch (also in this repo history is not
available here since this is a squashed snapshot; full incremental history
lives in the local DL380 checkout and the upstream GitHub remote).

Upstream: https://github.com/xiaomi-mt6833-dev/kernel_xiaomi_mt6833 (lineage-23.2)
2026-09-12 13:36:46 +00:00

89 lines
2.2 KiB
C

/*
* vdso_restorer.c - tests vDSO-based signal restore
* Copyright (c) 2015 Andrew Lutomirski
*
* This program is free software; you can redistribute it and/or modify
* it under the terms and conditions of the GNU General Public License,
* version 2, as published by the Free Software Foundation.
*
* This program is distributed in the hope it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
*
* This makes sure that sa_restorer == NULL keeps working on 32-bit
* configurations. Modern glibc doesn't use it under any circumstances,
* so it's easy to overlook breakage.
*
* 64-bit userspace has never supported sa_restorer == NULL, so this is
* 32-bit only.
*/
#define _GNU_SOURCE
#include <err.h>
#include <stdio.h>
#include <string.h>
#include <signal.h>
#include <unistd.h>
#include <syscall.h>
#include <sys/syscall.h>
/* Open-code this -- the headers are too messy to easily use them. */
struct real_sigaction {
void *handler;
unsigned long flags;
void *restorer;
unsigned int mask[2];
};
static volatile sig_atomic_t handler_called;
static void handler_with_siginfo(int sig, siginfo_t *info, void *ctx_void)
{
handler_called = 1;
}
static void handler_without_siginfo(int sig)
{
handler_called = 1;
}
int main()
{
int nerrs = 0;
struct real_sigaction sa;
memset(&sa, 0, sizeof(sa));
sa.handler = handler_with_siginfo;
sa.flags = SA_SIGINFO;
sa.restorer = NULL; /* request kernel-provided restorer */
if (syscall(SYS_rt_sigaction, SIGUSR1, &sa, NULL, 8) != 0)
err(1, "raw rt_sigaction syscall");
raise(SIGUSR1);
if (handler_called) {
printf("[OK]\tSA_SIGINFO handler returned successfully\n");
} else {
printf("[FAIL]\tSA_SIGINFO handler was not called\n");
nerrs++;
}
sa.flags = 0;
sa.handler = handler_without_siginfo;
if (syscall(SYS_sigaction, SIGUSR1, &sa, 0) != 0)
err(1, "raw sigaction syscall");
handler_called = 0;
raise(SIGUSR1);
if (handler_called) {
printf("[OK]\t!SA_SIGINFO handler returned successfully\n");
} else {
printf("[FAIL]\t!SA_SIGINFO handler was not called\n");
nerrs++;
}
}