mirror of
https://github.com/jart/cosmopolitan.git
synced 2025-02-15 10:47:56 +00:00
d1d4388201
It hasn't been helpful enough to be justify the maintenance burden. What actually does help is mprotect(), kprintf(), --ftrace and --strace which can always be counted upon to work correctly. We aren't losing much with this change. Support for ASAN on AARCH64 was never implemented. Applying ASAN to the core libc runtimes was disabled many months ago. If there is some way to have an ASAN runtime for user programs that is less invasive we can potentially consider reintroducing support. But now is premature.
418 lines
13 KiB
C
418 lines
13 KiB
C
/*-*- mode:c;indent-tabs-mode:nil;c-basic-offset:2;tab-width:8;coding:utf-8 -*-│
|
|
│ vi: set et ft=c ts=2 sts=2 sw=2 fenc=utf-8 :vi │
|
|
╞══════════════════════════════════════════════════════════════════════════════╡
|
|
│ Copyright 2021 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/struct/sigaction.h"
|
|
#include "libc/calls/calls.h"
|
|
#include "libc/calls/internal.h"
|
|
#include "libc/calls/pledge.h"
|
|
#include "libc/calls/struct/rusage.h"
|
|
#include "libc/calls/struct/sigaction.h"
|
|
#include "libc/calls/struct/siginfo.h"
|
|
#include "libc/calls/struct/sigset.h"
|
|
#include "libc/calls/struct/sigset.internal.h"
|
|
#include "libc/calls/struct/ucontext.internal.h"
|
|
#include "libc/calls/syscall_support-sysv.internal.h"
|
|
#include "libc/calls/ucontext.h"
|
|
#include "libc/dce.h"
|
|
#include "libc/errno.h"
|
|
#include "libc/nexgen32e/nexgen32e.h"
|
|
#include "libc/nexgen32e/vendor.internal.h"
|
|
#include "libc/runtime/internal.h"
|
|
#include "libc/runtime/runtime.h"
|
|
#include "libc/runtime/syslib.internal.h"
|
|
#include "libc/str/str.h"
|
|
#include "libc/sysv/consts/sa.h"
|
|
#include "libc/sysv/consts/sig.h"
|
|
#include "libc/sysv/consts/uc.h"
|
|
#include "libc/testlib/subprocess.h"
|
|
#include "libc/testlib/testlib.h"
|
|
#include "libc/thread/thread.h"
|
|
#include "third_party/xed/x86.h"
|
|
|
|
struct sigaction oldsa;
|
|
volatile bool gotsigint;
|
|
|
|
void SetUpOnce(void) {
|
|
ASSERT_SYS(0, 0, pledge("stdio rpath proc", 0));
|
|
}
|
|
|
|
void OnSigInt(int sig) {
|
|
CheckStackIsAligned();
|
|
gotsigint = true;
|
|
}
|
|
|
|
void SetUp(void) {
|
|
gotsigint = false;
|
|
}
|
|
|
|
void TearDown(void) {
|
|
sigset_t ss;
|
|
sigprocmask(SIG_SETMASK, 0, &ss);
|
|
ASSERT_TRUE(sigisemptyset(&ss));
|
|
}
|
|
|
|
////////////////////////////////////////////////////////////////////////////////
|
|
// test that signal handlers expose cpu state, and let it be changed arbitrarily
|
|
|
|
void *Gateway(void *arg) {
|
|
__builtin_trap();
|
|
}
|
|
|
|
void PromisedLand(void *arg) {
|
|
sigset_t ss;
|
|
CheckStackIsAligned();
|
|
sigprocmask(SIG_SETMASK, 0, &ss);
|
|
ASSERT_TRUE(sigismember(&ss, SIGUSR1));
|
|
pthread_exit(arg);
|
|
}
|
|
|
|
void Teleporter(int sig, siginfo_t *si, void *ctx) {
|
|
ucontext_t *uc = ctx;
|
|
sigaddset(&uc->uc_sigmask, SIGUSR1);
|
|
uc->uc_mcontext.PC = (uintptr_t)PromisedLand;
|
|
uc->uc_mcontext.SP &= -16;
|
|
#ifdef __x86_64__
|
|
uc->uc_mcontext.SP -= 8;
|
|
#endif
|
|
}
|
|
|
|
TEST(sigaction, handlersCanMutateMachineState) {
|
|
void *rc;
|
|
sigset_t ss;
|
|
pthread_t t;
|
|
struct sigaction oldill, oldtrap;
|
|
struct sigaction sa = {.sa_sigaction = Teleporter, .sa_flags = SA_SIGINFO};
|
|
sigprocmask(SIG_SETMASK, 0, &ss);
|
|
ASSERT_FALSE(sigismember(&ss, SIGUSR1));
|
|
ASSERT_SYS(0, 0, sigaction(SIGILL, &sa, &oldill));
|
|
ASSERT_SYS(0, 0, sigaction(SIGTRAP, &sa, &oldtrap));
|
|
ASSERT_EQ(0, pthread_create(&t, 0, Gateway, (void *)42L));
|
|
ASSERT_EQ(0, pthread_join(t, &rc));
|
|
ASSERT_EQ(42, (uintptr_t)rc);
|
|
ASSERT_SYS(0, 0, sigaction(SIGILL, &oldill, 0));
|
|
ASSERT_SYS(0, 0, sigaction(SIGTRAP, &oldtrap, 0));
|
|
}
|
|
|
|
////////////////////////////////////////////////////////////////////////////////
|
|
// test raise()
|
|
|
|
TEST(sigaction, raise) {
|
|
struct sigaction saint = {.sa_handler = OnSigInt};
|
|
EXPECT_SYS(0, 0, sigaction(SIGINT, &saint, &oldsa));
|
|
ASSERT_FALSE(gotsigint);
|
|
EXPECT_NE(-1, raise(SIGINT));
|
|
ASSERT_TRUE(gotsigint);
|
|
EXPECT_SYS(0, 0, sigaction(SIGINT, &oldsa, NULL));
|
|
}
|
|
|
|
////////////////////////////////////////////////////////////////////////////////
|
|
// test kill()
|
|
|
|
TEST(sigaction, testPingPongParentChildWithSigint) {
|
|
if (IsNetbsd())
|
|
return; // TODO: what's up with runitd on netbsd?
|
|
int pid, status;
|
|
sigset_t blockint, oldmask;
|
|
struct sigaction oldint;
|
|
struct sigaction ignoreint = {.sa_handler = SIG_IGN};
|
|
struct sigaction catchint = {.sa_handler = OnSigInt};
|
|
if (IsWindows()) {
|
|
// this works if it's run by itself on the command prompt. but it
|
|
// doesn't currently work if it's launched as a subprocess of some
|
|
// kind of runner. todo(fixme!)
|
|
return;
|
|
}
|
|
EXPECT_SYS(0, 0, sigemptyset(&blockint));
|
|
EXPECT_SYS(0, 0, sigaddset(&blockint, SIGINT));
|
|
EXPECT_SYS(0, 0, sigprocmask(SIG_BLOCK, &blockint, &oldmask));
|
|
EXPECT_SYS(0, 0, sigaction(SIGINT, &catchint, &oldint));
|
|
ASSERT_NE(-1, (pid = fork()));
|
|
if (!pid) {
|
|
// ping
|
|
EXPECT_SYS(0, 0, kill(getppid(), SIGINT));
|
|
EXPECT_FALSE(gotsigint);
|
|
// pong
|
|
EXPECT_SYS(0, 0, sigaction(SIGINT, &catchint, 0));
|
|
EXPECT_SYS(EINTR, -1, sigsuspend(0));
|
|
EXPECT_TRUE(gotsigint);
|
|
_exit(0);
|
|
}
|
|
// pong
|
|
EXPECT_FALSE(gotsigint);
|
|
EXPECT_SYS(0, 0, sigaction(SIGINT, &catchint, 0));
|
|
EXPECT_SYS(EINTR, -1, sigsuspend(0));
|
|
EXPECT_TRUE(gotsigint);
|
|
// ping
|
|
EXPECT_SYS(0, 0, sigaction(SIGINT, &ignoreint, 0));
|
|
EXPECT_SYS(0, 0, kill(pid, SIGINT));
|
|
// cleanup
|
|
EXPECT_NE(-1, wait4(pid, &status, 0, 0));
|
|
EXPECT_EQ(1, WIFEXITED(status));
|
|
EXPECT_EQ(0, WEXITSTATUS(status));
|
|
EXPECT_EQ(0, WTERMSIG(status));
|
|
EXPECT_SYS(0, 0, sigaction(SIGINT, &oldint, 0));
|
|
EXPECT_SYS(0, 0, sigprocmask(SIG_SETMASK, &oldmask, 0));
|
|
}
|
|
|
|
#ifdef __x86_64__
|
|
|
|
////////////////////////////////////////////////////////////////////////////////
|
|
// test int3 crash
|
|
// we expect this to be recoverable by default
|
|
|
|
volatile int trapeax;
|
|
|
|
void OnTrap(int sig, siginfo_t *si, void *vctx) {
|
|
struct ucontext *ctx = vctx;
|
|
CheckStackIsAligned();
|
|
trapeax = ctx->uc_mcontext.rax;
|
|
}
|
|
|
|
TEST(sigaction, debugBreak_handlerCanReadCpuState) {
|
|
struct sigaction saint = {.sa_sigaction = OnTrap, .sa_flags = SA_SIGINFO};
|
|
EXPECT_NE(-1, sigaction(SIGTRAP, &saint, &oldsa));
|
|
asm("int3" : /* no outputs */ : "a"(0x31337));
|
|
EXPECT_EQ(0x31337, trapeax);
|
|
EXPECT_SYS(0, 0, sigaction(SIGTRAP, &oldsa, NULL));
|
|
}
|
|
|
|
////////////////////////////////////////////////////////////////////////////////
|
|
// test fpu crash (unrecoverable)
|
|
// test signal handler can modify cpu registers (now it's recoverable!)
|
|
|
|
void SkipOverFaultingInstruction(struct ucontext *ctx) {
|
|
CheckStackIsAligned();
|
|
struct XedDecodedInst xedd;
|
|
xed_decoded_inst_zero_set_mode(&xedd, XED_MACHINE_MODE_LONG_64);
|
|
xed_instruction_length_decode(&xedd, (void *)ctx->uc_mcontext.rip, 15);
|
|
ctx->uc_mcontext.rip += xedd.length;
|
|
}
|
|
|
|
void OnFpe(int sig, siginfo_t *si, void *vctx) {
|
|
struct ucontext *ctx = vctx;
|
|
CheckStackIsAligned();
|
|
SkipOverFaultingInstruction(ctx);
|
|
ctx->uc_mcontext.rax = 42;
|
|
ctx->uc_mcontext.rdx = 0;
|
|
}
|
|
|
|
dontubsan void ubsanTrumpsSystemsEngineering(void) {
|
|
struct sigaction saint = {.sa_sigaction = OnFpe, .sa_flags = SA_SIGINFO};
|
|
EXPECT_SYS(0, 0, sigaction(SIGFPE, &saint, &oldsa));
|
|
volatile long x = 0;
|
|
EXPECT_EQ(42, 666 / x); /* systems engineering trumps math */
|
|
EXPECT_SYS(0, 0, sigaction(SIGFPE, &oldsa, NULL));
|
|
}
|
|
|
|
TEST(sigaction, sigFpe_handlerCanEditProcessStateAndRecoverExecution) {
|
|
ubsanTrumpsSystemsEngineering();
|
|
}
|
|
|
|
#endif /* __x86_64__ */
|
|
|
|
static unsigned OnSignalCnt = 0;
|
|
void OnSignal(int sig, siginfo_t *si, void *ctx) {
|
|
OnSignalCnt++;
|
|
}
|
|
|
|
TEST(sigaction, ignoringSignalDiscardsSignal) {
|
|
struct sigaction sa = {.sa_sigaction = OnSignal, .sa_flags = SA_SIGINFO};
|
|
ASSERT_EQ(0, sigaction(SIGUSR1, &sa, NULL));
|
|
sigset_t blocked, oldmask;
|
|
sigemptyset(&blocked);
|
|
sigaddset(&blocked, SIGUSR1);
|
|
ASSERT_EQ(0, sigprocmask(SIG_SETMASK, &blocked, &oldmask));
|
|
ASSERT_EQ(0, raise(SIGUSR1));
|
|
ASSERT_NE(SIG_ERR, signal(SIGUSR1, SIG_IGN));
|
|
ASSERT_EQ(0, sigaction(SIGUSR1, &sa, NULL));
|
|
ASSERT_EQ(0, sigprocmask(SIG_SETMASK, &oldmask, NULL));
|
|
EXPECT_EQ(0, OnSignalCnt);
|
|
}
|
|
|
|
TEST(sigaction, autoZombieSlayer) {
|
|
if (IsWindows())
|
|
return;
|
|
if (IsCygwin())
|
|
return;
|
|
int pid;
|
|
struct sigaction sa;
|
|
// make sure we're starting in expected state
|
|
ASSERT_SYS(0, 0, sigaction(SIGCHLD, 0, &sa));
|
|
ASSERT_EQ(SIG_DFL, sa.sa_handler);
|
|
// verify child becomes zombie
|
|
ASSERT_NE(-1, (pid = fork()));
|
|
if (!pid)
|
|
_Exit(0);
|
|
ASSERT_SYS(0, pid, wait(0));
|
|
// enable automatic zombie slayer
|
|
sa.sa_handler = SIG_IGN;
|
|
sa.sa_flags = 0;
|
|
sigemptyset(&sa.sa_mask);
|
|
ASSERT_SYS(0, 0, sigaction(SIGCHLD, &sa, &sa));
|
|
// verify it works
|
|
ASSERT_NE(-1, (pid = fork()));
|
|
if (!pid)
|
|
_Exit(0);
|
|
// XXX: WSL does the wrong thing here.
|
|
if (__iswsl1())
|
|
usleep(10);
|
|
ASSERT_SYS(ECHILD, -1, wait(0));
|
|
// clean up
|
|
ASSERT_SYS(0, 0, sigaction(SIGCHLD, &sa, 0));
|
|
}
|
|
|
|
TEST(sigaction, enosys_returnsErrnoRatherThanSigsysByDefault) {
|
|
if (IsTiny())
|
|
return; // systemfive.S disables the fix w/ tiny
|
|
if (IsOpenbsd())
|
|
return; // TODO: Why does OpenBSD raise SIGABRT?
|
|
ASSERT_SYS(ENOSYS, -1, sys_bogus());
|
|
}
|
|
|
|
sig_atomic_t gotusr1;
|
|
|
|
void OnSigMask(int sig, siginfo_t *si, void *ctx) {
|
|
ucontext_t *uc = ctx;
|
|
sigaddset(&uc->uc_sigmask, sig);
|
|
gotusr1 = true;
|
|
}
|
|
|
|
TEST(uc_sigmask, signalHandlerCanChangeSignalMaskOfTrappedThread) {
|
|
sigset_t want, got;
|
|
struct sigaction oldsa;
|
|
struct sigaction sa = {.sa_sigaction = OnSigMask, .sa_flags = SA_SIGINFO};
|
|
sigemptyset(&want);
|
|
ASSERT_SYS(0, 0, sigprocmask(SIG_SETMASK, &want, &got));
|
|
ASSERT_FALSE(sigismember(&got, SIGUSR1));
|
|
ASSERT_SYS(0, 0, sigaction(SIGUSR1, &sa, &oldsa));
|
|
ASSERT_SYS(0, 0, raise(SIGUSR1));
|
|
ASSERT_TRUE(gotusr1);
|
|
ASSERT_SYS(0, 0, sigprocmask(SIG_SETMASK, 0, &got));
|
|
ASSERT_TRUE(sigismember(&got, SIGUSR1));
|
|
sigaddset(&want, SIGUSR1);
|
|
ASSERT_EQ(0, errno);
|
|
ASSERT_STREQ(DescribeSigset(0, &want), DescribeSigset(0, &got));
|
|
ASSERT_EQ(0, errno);
|
|
ASSERT_SYS(0, 0, sigaction(SIGUSR1, &oldsa, 0));
|
|
sigdelset(&want, SIGUSR1);
|
|
ASSERT_SYS(0, 0, sigprocmask(SIG_SETMASK, &want, 0));
|
|
}
|
|
|
|
TEST(sig_ign, discardsPendingSignalsEvenIfBlocked) {
|
|
sigset_t block, oldmask;
|
|
struct sigaction sa, oldsa;
|
|
ASSERT_SYS(0, 0, sigemptyset(&block));
|
|
ASSERT_SYS(0, 0, sigaddset(&block, SIGUSR1));
|
|
ASSERT_SYS(0, 0, sigprocmask(SIG_BLOCK, &block, &oldmask));
|
|
raise(SIGUSR1); // enqueue
|
|
sa.sa_flags = 0;
|
|
sa.sa_handler = SIG_IGN;
|
|
ASSERT_SYS(0, 0, sigemptyset(&sa.sa_mask));
|
|
ASSERT_SYS(0, 0, sigaction(SIGUSR1, &sa, &oldsa)); // discard
|
|
ASSERT_SYS(0, 0, sigprocmask(SIG_UNBLOCK, &block, 0));
|
|
ASSERT_SYS(0, 0, sigaction(SIGUSR1, &oldsa, 0));
|
|
ASSERT_SYS(0, 0, sigprocmask(SIG_SETMASK, &oldmask, 0));
|
|
}
|
|
|
|
void AutoMask(int sig, siginfo_t *si, void *ctx) {
|
|
sigset_t ss;
|
|
ucontext_t *uc = ctx;
|
|
sigprocmask(SIG_SETMASK, 0, &ss);
|
|
EXPECT_FALSE(sigismember(&uc->uc_sigmask, SIGUSR2)); // original mask
|
|
EXPECT_TRUE(sigismember(&ss, SIGUSR2)); // temporary mask
|
|
}
|
|
|
|
TEST(sigaction, signalBeingDeliveredGetsAutoMasked) {
|
|
sigset_t ss;
|
|
struct sigaction os, sa = {.sa_sigaction = AutoMask, .sa_flags = SA_SIGINFO};
|
|
ASSERT_SYS(0, 0, sigaction(SIGUSR2, &sa, &os));
|
|
raise(SIGUSR2);
|
|
ASSERT_SYS(0, 0, sigaction(SIGUSR2, &os, 0));
|
|
sigprocmask(SIG_SETMASK, 0, &ss);
|
|
EXPECT_FALSE(sigismember(&ss, SIGUSR2)); // original mask
|
|
}
|
|
|
|
void NoDefer(int sig, siginfo_t *si, void *ctx) {
|
|
sigset_t ss;
|
|
ucontext_t *uc = ctx;
|
|
sigprocmask(SIG_SETMASK, 0, &ss);
|
|
EXPECT_FALSE(sigismember(&uc->uc_sigmask, SIGUSR2));
|
|
EXPECT_FALSE(sigismember(&ss, SIGUSR2));
|
|
}
|
|
|
|
TEST(sigaction, NoDefer) {
|
|
struct sigaction os;
|
|
struct sigaction sa = {
|
|
.sa_sigaction = NoDefer,
|
|
.sa_flags = SA_SIGINFO | SA_NODEFER,
|
|
};
|
|
ASSERT_SYS(0, 0, sigaction(SIGUSR2, &sa, &os));
|
|
raise(SIGUSR2);
|
|
ASSERT_SYS(0, 0, sigaction(SIGUSR2, &os, 0));
|
|
}
|
|
|
|
int *segfaults;
|
|
|
|
void OnSegfault(int sig) {
|
|
if (++*segfaults == 10000) {
|
|
_Exit(0);
|
|
}
|
|
}
|
|
|
|
dontubsan int Segfault(char *p) {
|
|
return *p;
|
|
}
|
|
|
|
int (*pSegfault)(char *) = Segfault;
|
|
|
|
TEST(sigaction, returnFromSegvHandler_loopsForever) {
|
|
if (IsXnu())
|
|
return; // seems busted
|
|
segfaults = _mapshared(sizeof(*segfaults));
|
|
SPAWN(fork);
|
|
signal(SIGSEGV, OnSegfault);
|
|
_Exit(pSegfault(0));
|
|
EXITS(0);
|
|
ASSERT_EQ(10000, *segfaults);
|
|
munmap(segfaults, sizeof(*segfaults));
|
|
}
|
|
|
|
#if 0
|
|
TEST(sigaction, ignoreSigSegv_notPossible) {
|
|
if (IsXnu()) return; // seems busted
|
|
SPAWN(fork);
|
|
signal(SIGSEGV, SIG_IGN);
|
|
_Exit(pSegfault(0));
|
|
TERMS(SIGSEGV);
|
|
}
|
|
|
|
TEST(sigaction, killSigSegv_canBeIgnored) {
|
|
int child, ws;
|
|
if (IsWindows()) return; // TODO
|
|
sighandler_t old = signal(SIGSEGV, SIG_IGN);
|
|
ASSERT_NE(-1, (child = fork()));
|
|
while (!child) {
|
|
pause();
|
|
}
|
|
ASSERT_SYS(0, 0, kill(child, SIGSEGV));
|
|
EXPECT_SYS(0, 0, kill(child, SIGTERM));
|
|
EXPECT_SYS(0, child, wait(&ws));
|
|
EXPECT_EQ(SIGTERM, ws);
|
|
signal(SIGSEGV, old);
|
|
}
|
|
#endif
|