cosmopolitan/libc/intrin/exit1.greg.c
Justine Tunney 0277d7d6e9 Rewrite Linux pledge() code so it can be a payload
It's now possible to build our pledge() polyfill as a dynamic shared
object that can be injected into a glibc executable using LD_PRELOAD
2022-08-08 11:41:08 -07:00

56 lines
2.8 KiB
C

/*-*- mode:c;indent-tabs-mode:nil;c-basic-offset:2;tab-width:8;coding:utf-8 -*-│
│vi: set net ft=c ts=2 sts=2 sw=2 fenc=utf-8 :vi│
╞══════════════════════════════════════════════════════════════════════════════╡
│ Copyright 2022 Justine Alexandra Roberts Tunney │
│ │
│ Permission to use, copy, modify, and/or distribute this software for │
│ any purpose with or without fee is hereby granted, provided that the │
│ above copyright notice and this permission notice appear in all copies. │
│ │
│ THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL │
│ WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED │
│ WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE │
│ AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL │
│ DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR │
│ PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER │
│ TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR │
│ PERFORMANCE OF THIS SOFTWARE. │
╚─────────────────────────────────────────────────────────────────────────────*/
#include "libc/calls/strace.internal.h"
#include "libc/dce.h"
#include "libc/intrin/kprintf.h"
#include "libc/intrin/promises.internal.h"
#include "libc/nt/thread.h"
#include "libc/runtime/runtime.h"
#include "libc/sysv/consts/nr.h"
/**
* Terminates thread with raw system call.
*
* @param rc only works on Linux and Windows
* @see cthread_exit()
* @threadsafe
* @noreturn
*/
privileged wontreturn void _Exit1(int rc) {
struct WinThread *wt;
STRACE("_Exit1(%d)", rc);
if (!IsWindows() && !IsMetal()) {
if (IsOpenbsd() && !PLEDGED(STDIO)) {
asm volatile("syscall"
: /* no outputs */
: "a"(__NR_exit), "D"(rc)
: "rcx", "r11", "memory");
}
asm volatile("xor\t%%r10d,%%r10d\n\t"
"syscall"
: /* no outputs */
: "a"(__NR_exit), "D"(IsLinux() ? rc : 0), "S"(0), "d"(0)
: "rcx", "r10", "r11", "memory");
} else if (IsWindows()) {
ExitThread(rc);
}
for (;;) {
asm("ud2");
}
}