xref: /third_party/musl/src/exit/abort.c (revision 570af302)
1#include <stdlib.h>
2#include <signal.h>
3#include "syscall.h"
4#include "pthread_impl.h"
5#include "atomic.h"
6#include "lock.h"
7#include "ksigaction.h"
8#if defined(MUSL_AARCH64_ARCH)
9#include <stdint.h>
10#include <stdio.h>
11#include <inttypes.h>
12#include <info/fatal_message.h>
13
14#define MESSAGE_BUFFER_SIZE 512
15
16/**
17 * @brief Retrieves the current value of the x1 register on AArch64.
18 *
19 * This function is used in CFI checks to obtain the function address
20 * stored in the x1 register during calls involving function pointers,
21 * virtual calls (vcall), and non-virtual calls (nvcall) using vtable addresses.
22 *
23 * @return Value of the x1 register.
24 */
25uint64_t fetch_function_address()
26{
27	uint64_t val;
28	__asm__ __volatile__(
29		"mov %0, x1"
30		: "=r" (val)
31		:
32		: "memory"
33	);
34	return val;
35}
36#endif
37
38_Noreturn void __cfi_fail_report(void)
39{
40#if defined(MUSL_AARCH64_ARCH)
41	uint64_t function_address = fetch_function_address();
42	char message[MESSAGE_BUFFER_SIZE];
43	snprintf(message, sizeof(message),
44			" CFI check failed. Function Address: 0x%" PRIx64, function_address);
45	set_fatal_message(message);
46#endif
47	abort();
48}
49
50_Noreturn void abort(void)
51{
52#ifdef __LITEOS_A__
53	sigset_t set, pending;
54	sigemptyset(&set);
55	sigaddset(&set, SIGABRT);
56
57	sigpending(&pending);
58	__syscall(SYS_rt_sigprocmask, SIG_UNBLOCK, &set, 0, _NSIG / 8);
59	if (!sigismember(&pending, SIGABRT)) {
60		raise(SIGABRT);
61	}
62#else
63	raise(SIGABRT);
64#endif
65
66	/* If there was a SIGABRT handler installed and it returned, or if
67	 * SIGABRT was blocked or ignored, take an AS-safe lock to prevent
68	 * sigaction from installing a new SIGABRT handler, uninstall any
69	 * handler that may be present, and re-raise the signal to generate
70	 * the default action of abnormal termination. */
71	__block_all_sigs(0);
72	LOCK(__abort_lock);
73#ifdef __LITEOS_A__
74	signal(SIGABRT, SIG_DFL);
75#else
76	__syscall(SYS_rt_sigaction, SIGABRT,
77		&(struct k_sigaction){.handler = SIG_DFL}, 0, _NSIG/8);
78#endif
79	__syscall(SYS_tkill, __pthread_self()->tid, SIGABRT);
80	__syscall(SYS_rt_sigprocmask, SIG_UNBLOCK,
81		&(long[_NSIG/(8*sizeof(long))]){1UL<<(SIGABRT-1)}, 0, _NSIG/8);
82
83	/* Beyond this point should be unreachable. */
84	a_crash();
85	raise(SIGKILL);
86	_Exit(127);
87}
88