/* * 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++; } } ' value='d166f56bf58b64027679905a01001df9ac0764bd'/><select name='qt'> <option value='grep'>log msg</option> <option value='author'>author</option> <option value='committer'>committer</option> <option value='range'>range</option> </select> <input class='txt' type='search' size='10' name='q' value=''/> <input type='submit' value='search'/> </form> </td></tr></table> <div class='path'>path: <a href='/cgit.cgi/linux/net-next.git/log/?id=d166f56bf58b64027679905a01001df9ac0764bd'>root</a>/<a href='/cgit.cgi/linux/net-next.git/log/sound?id=d166f56bf58b64027679905a01001df9ac0764bd'>sound</a>/<a href='/cgit.cgi/linux/net-next.git/log/sound/soc?id=d166f56bf58b64027679905a01001df9ac0764bd'>soc</a>/<a href='/cgit.cgi/linux/net-next.git/log/sound/soc/zte?id=d166f56bf58b64027679905a01001df9ac0764bd'>zte</a>/<a href='/cgit.cgi/linux/net-next.git/log/sound/soc/zte/zx-spdif.c?id=d166f56bf58b64027679905a01001df9ac0764bd'>zx-spdif.c</a></div><div class='content'><table class='list nowrap'><tr class='nohover'><th class='left'>Age</th><th class='left'>Commit message (<a href='/cgit.cgi/linux/net-next.git/log/sound/soc/zte/zx-spdif.c?id=d166f56bf58b64027679905a01001df9ac0764bd&showmsg=1'>Expand</a>)</th><th class='left'>Author</th><th class='left'>Files</th><th class='left'>Lines</th></tr>