1// SPDX-License-Identifier: GPL-2.0
 2/*
 3 * Copyright (C) 2002 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com)
 
 4 */
 5
 6#include <linux/kernel.h>
 7#include <linux/ptrace.h>
 8#include <linux/seccomp.h>
 9#include <kern_util.h>
10#include <sysdep/ptrace.h>
11#include <sysdep/ptrace_user.h>
12#include <sysdep/syscalls.h>
13#include <linux/time-internal.h>
14#include <asm/unistd.h>
15
16void handle_syscall(struct uml_pt_regs *r)
17{
18	struct pt_regs *regs = container_of(r, struct pt_regs, regs);
 
19	int syscall;
20
 
 
21	/*
22	 * If we have infinite CPU resources, then make every syscall also a
23	 * preemption point, since we don't have any other preemption in this
24	 * case, and kernel threads would basically never run until userspace
25	 * went to sleep, even if said userspace interacts with the kernel in
26	 * various ways.
 
 
27	 */
28	if (time_travel_mode == TT_MODE_INFCPU ||
29	    time_travel_mode == TT_MODE_EXTERNAL)
30		schedule();
31
32	/* Initialize the syscall number and default return value. */
33	UPT_SYSCALL_NR(r) = PT_SYSCALL_NR(r->gp);
34	PT_REGS_SET_SYSCALL_RETURN(regs, -ENOSYS);
35
36	if (syscall_trace_enter(regs))
37		goto out;
38
39	/* Do the seccomp check after ptrace; failures should be fast. */
40	if (secure_computing() == -1)
41		goto out;
42
43	syscall = UPT_SYSCALL_NR(r);
44	if (syscall >= 0 && syscall <= __NR_syscall_max)
45		PT_REGS_SET_SYSCALL_RETURN(regs,
46				EXECUTE_SYSCALL(syscall, regs));
 
 
47
48out:
49	syscall_trace_leave(regs);
50}

 
 1/*
 2 * Copyright (C) 2002 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com)
 3 * Licensed under the GPL
 4 */
 5
 6#include "linux/kernel.h"
 7#include "linux/ptrace.h"
 8#include "kern_util.h"
 9#include "sysdep/ptrace.h"
10#include "sysdep/syscalls.h"
11
12extern int syscall_table_size;
13#define NR_SYSCALLS (syscall_table_size / sizeof(void *))
 
14
15void handle_syscall(struct uml_pt_regs *r)
16{
17	struct pt_regs *regs = container_of(r, struct pt_regs, regs);
18	long result;
19	int syscall;
20
21	syscall_trace(r, 0);
22
23	/*
24	 * This should go in the declaration of syscall, but when I do that,
25	 * strace -f -c bash -c 'ls ; ls' breaks, sometimes not tracing
26	 * children at all, sometimes hanging when bash doesn't see the first
27	 * ls exit.
28	 * The assembly looks functionally the same to me.  This is
29	 *     gcc version 4.0.1 20050727 (Red Hat 4.0.1-5)
30	 * in case it's a compiler bug.
31	 */
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
32	syscall = UPT_SYSCALL_NR(r);
33	if ((syscall >= NR_SYSCALLS) || (syscall < 0))
34		result = -ENOSYS;
35	else result = EXECUTE_SYSCALL(syscall, regs);
36
37	UPT_SET_SYSCALL_RETURN(r, result);
38
39	syscall_trace(r, 1);
 
40}