mirror of
https://mirrors.bfsu.edu.cn/git/linux.git
synced 2024-12-05 10:04:12 +08:00
df561f6688
Replace the existing /* fall through */ comments and its variants with the new pseudo-keyword macro fallthrough[1]. Also, remove unnecessary fall-through markings when it is the case. [1] https://www.kernel.org/doc/html/v5.7/process/deprecated.html?highlight=fallthrough#implicit-switch-case-fall-through Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
142 lines
3.3 KiB
C
142 lines
3.3 KiB
C
// SPDX-License-Identifier: GPL-2.0
|
|
/*
|
|
* Copyright (C) 2000 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com)
|
|
*/
|
|
|
|
#include <linux/module.h>
|
|
#include <linux/ptrace.h>
|
|
#include <linux/sched.h>
|
|
#include <linux/ftrace.h>
|
|
#include <asm/siginfo.h>
|
|
#include <asm/signal.h>
|
|
#include <asm/unistd.h>
|
|
#include <frame_kern.h>
|
|
#include <kern_util.h>
|
|
#include <os.h>
|
|
|
|
EXPORT_SYMBOL(block_signals);
|
|
EXPORT_SYMBOL(unblock_signals);
|
|
|
|
void block_signals_trace(void)
|
|
{
|
|
block_signals();
|
|
if (current_thread_info())
|
|
trace_hardirqs_off();
|
|
}
|
|
|
|
void unblock_signals_trace(void)
|
|
{
|
|
if (current_thread_info())
|
|
trace_hardirqs_on();
|
|
unblock_signals();
|
|
}
|
|
|
|
void um_trace_signals_on(void)
|
|
{
|
|
if (current_thread_info())
|
|
trace_hardirqs_on();
|
|
}
|
|
|
|
void um_trace_signals_off(void)
|
|
{
|
|
if (current_thread_info())
|
|
trace_hardirqs_off();
|
|
}
|
|
|
|
/*
|
|
* OK, we're invoking a handler
|
|
*/
|
|
static void handle_signal(struct ksignal *ksig, struct pt_regs *regs)
|
|
{
|
|
sigset_t *oldset = sigmask_to_save();
|
|
int singlestep = 0;
|
|
unsigned long sp;
|
|
int err;
|
|
|
|
if ((current->ptrace & PT_DTRACE) && (current->ptrace & PT_PTRACED))
|
|
singlestep = 1;
|
|
|
|
/* Did we come from a system call? */
|
|
if (PT_REGS_SYSCALL_NR(regs) >= 0) {
|
|
/* If so, check system call restarting.. */
|
|
switch (PT_REGS_SYSCALL_RET(regs)) {
|
|
case -ERESTART_RESTARTBLOCK:
|
|
case -ERESTARTNOHAND:
|
|
PT_REGS_SYSCALL_RET(regs) = -EINTR;
|
|
break;
|
|
|
|
case -ERESTARTSYS:
|
|
if (!(ksig->ka.sa.sa_flags & SA_RESTART)) {
|
|
PT_REGS_SYSCALL_RET(regs) = -EINTR;
|
|
break;
|
|
}
|
|
fallthrough;
|
|
case -ERESTARTNOINTR:
|
|
PT_REGS_RESTART_SYSCALL(regs);
|
|
PT_REGS_ORIG_SYSCALL(regs) = PT_REGS_SYSCALL_NR(regs);
|
|
break;
|
|
}
|
|
}
|
|
|
|
sp = PT_REGS_SP(regs);
|
|
if ((ksig->ka.sa.sa_flags & SA_ONSTACK) && (sas_ss_flags(sp) == 0))
|
|
sp = current->sas_ss_sp + current->sas_ss_size;
|
|
|
|
#ifdef CONFIG_ARCH_HAS_SC_SIGNALS
|
|
if (!(ksig->ka.sa.sa_flags & SA_SIGINFO))
|
|
err = setup_signal_stack_sc(sp, ksig, regs, oldset);
|
|
else
|
|
#endif
|
|
err = setup_signal_stack_si(sp, ksig, regs, oldset);
|
|
|
|
signal_setup_done(err, ksig, singlestep);
|
|
}
|
|
|
|
void do_signal(struct pt_regs *regs)
|
|
{
|
|
struct ksignal ksig;
|
|
int handled_sig = 0;
|
|
|
|
while (get_signal(&ksig)) {
|
|
handled_sig = 1;
|
|
/* Whee! Actually deliver the signal. */
|
|
handle_signal(&ksig, regs);
|
|
}
|
|
|
|
/* Did we come from a system call? */
|
|
if (!handled_sig && (PT_REGS_SYSCALL_NR(regs) >= 0)) {
|
|
/* Restart the system call - no handlers present */
|
|
switch (PT_REGS_SYSCALL_RET(regs)) {
|
|
case -ERESTARTNOHAND:
|
|
case -ERESTARTSYS:
|
|
case -ERESTARTNOINTR:
|
|
PT_REGS_ORIG_SYSCALL(regs) = PT_REGS_SYSCALL_NR(regs);
|
|
PT_REGS_RESTART_SYSCALL(regs);
|
|
break;
|
|
case -ERESTART_RESTARTBLOCK:
|
|
PT_REGS_ORIG_SYSCALL(regs) = __NR_restart_syscall;
|
|
PT_REGS_RESTART_SYSCALL(regs);
|
|
break;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* This closes a way to execute a system call on the host. If
|
|
* you set a breakpoint on a system call instruction and singlestep
|
|
* from it, the tracing thread used to PTRACE_SINGLESTEP the process
|
|
* rather than PTRACE_SYSCALL it, allowing the system call to execute
|
|
* on the host. The tracing thread will check this flag and
|
|
* PTRACE_SYSCALL if necessary.
|
|
*/
|
|
if (current->ptrace & PT_DTRACE)
|
|
current->thread.singlestep_syscall =
|
|
is_syscall(PT_REGS_IP(¤t->thread.regs));
|
|
|
|
/*
|
|
* if there's no signal to deliver, we just put the saved sigmask
|
|
* back
|
|
*/
|
|
if (!handled_sig)
|
|
restore_saved_sigmask();
|
|
}
|