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}

 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 <shared/timer-internal.h>
14
15void handle_syscall(struct uml_pt_regs *r)
16{
17	struct pt_regs *regs = container_of(r, struct pt_regs, regs);
 
18	int syscall;
19
 
 
20	/*
21	 * If we have infinite CPU resources, then make every syscall also a
22	 * preemption point, since we don't have any other preemption in this
23	 * case, and kernel threads would basically never run until userspace
24	 * went to sleep, even if said userspace interacts with the kernel in
25	 * various ways.
 
 
26	 */
27	if (time_travel_mode == TT_MODE_INFCPU)
28		schedule();
 
 
29
30	/* Initialize the syscall number and default return value. */
31	UPT_SYSCALL_NR(r) = PT_SYSCALL_NR(r->gp);
32	PT_REGS_SET_SYSCALL_RETURN(regs, -ENOSYS);
33
34	if (syscall_trace_enter(regs))
35		goto out;
36
37	/* Do the seccomp check after ptrace; failures should be fast. */
38	if (secure_computing(NULL) == -1)
39		goto out;
40
41	syscall = UPT_SYSCALL_NR(r);
42	if (syscall >= 0 && syscall <= __NR_syscall_max)
43		PT_REGS_SET_SYSCALL_RETURN(regs,
44				EXECUTE_SYSCALL(syscall, regs));
45
46out:
47	syscall_trace_leave(regs);
48}