From 8ac6c7a54ed1b98d142dce24b11c6de6a1e239a5 Mon Sep 17 00:00:00 2001
From: hc <hc@nodka.com>
Date: Tue, 22 Oct 2024 10:36:11 +0000
Subject: [PATCH] 修改4g拨号为QMI,需要在系统里后台执行quectel-CM
---
kernel/tools/testing/selftests/x86/single_step_syscall.c | 123 +++++++++++++++++++++++++++++-----------
1 files changed, 89 insertions(+), 34 deletions(-)
diff --git a/kernel/tools/testing/selftests/x86/single_step_syscall.c b/kernel/tools/testing/selftests/x86/single_step_syscall.c
index ddfdd63..120ac74 100644
--- a/kernel/tools/testing/selftests/x86/single_step_syscall.c
+++ b/kernel/tools/testing/selftests/x86/single_step_syscall.c
@@ -1,15 +1,7 @@
+// SPDX-License-Identifier: GPL-2.0-only
/*
* single_step_syscall.c - single-steps various x86 syscalls
* Copyright (c) 2014-2015 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 is a very simple series of tests that makes system calls with
* the TF flag set. This exercises some nasty kernel code in the
@@ -39,6 +31,8 @@
#include <sys/ptrace.h>
#include <sys/user.h>
+#include "helpers.h"
+
static void sethandler(int sig, void (*handler)(int, siginfo_t *, void *),
int flags)
{
@@ -51,7 +45,19 @@
err(1, "sigaction");
}
-static volatile sig_atomic_t sig_traps;
+static void clearhandler(int sig)
+{
+ struct sigaction sa;
+ memset(&sa, 0, sizeof(sa));
+ sa.sa_handler = SIG_DFL;
+ sigemptyset(&sa.sa_mask);
+ if (sigaction(sig, &sa, 0))
+ err(1, "sigaction");
+}
+
+static volatile sig_atomic_t sig_traps, sig_eflags;
+sigjmp_buf jmpbuf;
+static unsigned char altstack_data[SIGSTKSZ];
#ifdef __x86_64__
# define REG_IP REG_RIP
@@ -62,21 +68,6 @@
# define WIDTH "l"
# define INT80_CLOBBERS
#endif
-
-static unsigned long get_eflags(void)
-{
- unsigned long eflags;
- asm volatile ("pushf" WIDTH "\n\tpop" WIDTH " %0" : "=rm" (eflags));
- return eflags;
-}
-
-static void set_eflags(unsigned long eflags)
-{
- asm volatile ("push" WIDTH " %0\n\tpopf" WIDTH
- : : "rm" (eflags) : "flags");
-}
-
-#define X86_EFLAGS_TF (1UL << 8)
static void sigtrap(int sig, siginfo_t *info, void *ctx_void)
{
@@ -98,6 +89,25 @@
}
}
+static char const * const signames[] = {
+ [SIGSEGV] = "SIGSEGV",
+ [SIGBUS] = "SIBGUS",
+ [SIGTRAP] = "SIGTRAP",
+ [SIGILL] = "SIGILL",
+};
+
+static void print_and_longjmp(int sig, siginfo_t *si, void *ctx_void)
+{
+ ucontext_t *ctx = ctx_void;
+
+ printf("\tGot %s with RIP=%lx, TF=%ld\n", signames[sig],
+ (unsigned long)ctx->uc_mcontext.gregs[REG_IP],
+ (unsigned long)ctx->uc_mcontext.gregs[REG_EFL] & X86_EFLAGS_TF);
+
+ sig_eflags = (unsigned long)ctx->uc_mcontext.gregs[REG_EFL];
+ siglongjmp(jmpbuf, 1);
+}
+
static void check_result(void)
{
unsigned long new_eflags = get_eflags();
@@ -115,6 +125,22 @@
printf("[OK]\tSurvived with TF set and %d traps\n", (int)sig_traps);
sig_traps = 0;
+}
+
+static void fast_syscall_no_tf(void)
+{
+ sig_traps = 0;
+ printf("[RUN]\tFast syscall with TF cleared\n");
+ fflush(stdout); /* Force a syscall */
+ if (get_eflags() & X86_EFLAGS_TF) {
+ printf("[FAIL]\tTF is now set\n");
+ exit(1);
+ }
+ if (sig_traps) {
+ printf("[FAIL]\tGot SIGTRAP\n");
+ exit(1);
+ }
+ printf("[OK]\tNothing unexpected happened\n");
}
int main()
@@ -171,17 +197,46 @@
check_result();
/* Now make sure that another fast syscall doesn't set TF again. */
- printf("[RUN]\tFast syscall with TF cleared\n");
- fflush(stdout); /* Force a syscall */
- if (get_eflags() & X86_EFLAGS_TF) {
- printf("[FAIL]\tTF is now set\n");
+ fast_syscall_no_tf();
+
+ /*
+ * And do a forced SYSENTER to make sure that this works even if
+ * fast syscalls don't use SYSENTER.
+ *
+ * Invoking SYSENTER directly breaks all the rules. Just handle
+ * the SIGSEGV.
+ */
+ if (sigsetjmp(jmpbuf, 1) == 0) {
+ unsigned long nr = SYS_getpid;
+ printf("[RUN]\tSet TF and check SYSENTER\n");
+ stack_t stack = {
+ .ss_sp = altstack_data,
+ .ss_size = SIGSTKSZ,
+ };
+ if (sigaltstack(&stack, NULL) != 0)
+ err(1, "sigaltstack");
+ sethandler(SIGSEGV, print_and_longjmp,
+ SA_RESETHAND | SA_ONSTACK);
+ sethandler(SIGILL, print_and_longjmp, SA_RESETHAND);
+ set_eflags(get_eflags() | X86_EFLAGS_TF);
+ /* Clear EBP first to make sure we segfault cleanly. */
+ asm volatile ("xorl %%ebp, %%ebp; SYSENTER" : "+a" (nr) :: "flags", "rcx"
+#ifdef __x86_64__
+ , "r11"
+#endif
+ );
+
+ /* We're unreachable here. SYSENTER forgets RIP. */
+ }
+ clearhandler(SIGSEGV);
+ clearhandler(SIGILL);
+ if (!(sig_eflags & X86_EFLAGS_TF)) {
+ printf("[FAIL]\tTF was cleared\n");
exit(1);
}
- if (sig_traps) {
- printf("[FAIL]\tGot SIGTRAP\n");
- exit(1);
- }
- printf("[OK]\tNothing unexpected happened\n");
+
+ /* Now make sure that another fast syscall doesn't set TF again. */
+ fast_syscall_no_tf();
return 0;
}
--
Gitblit v1.6.2