kernel-fxtec-pro1x/arch/hexagon/kernel/syscall.c
Jeff Layton 91a27b2a75 vfs: define struct filename and have getname() return it
getname() is intended to copy pathname strings from userspace into a
kernel buffer. The result is just a string in kernel space. It would
however be quite helpful to be able to attach some ancillary info to
the string.

For instance, we could attach some audit-related info to reduce the
amount of audit-related processing needed. When auditing is enabled,
we could also call getname() on the string more than once and not
need to recopy it from userspace.

This patchset converts the getname()/putname() interfaces to return
a struct instead of a string. For now, the struct just tracks the
string in kernel space and the original userland pointer for it.

Later, we'll add other information to the struct as it becomes
convenient.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-10-12 20:14:55 -04:00

89 lines
2.5 KiB
C

/*
* Hexagon system calls
*
* Copyright (c) 2010-2011, Code Aurora Forum. All rights reserved.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 and
* only version 2 as published by the Free Software Foundation.
*
* This program is distributed in the hope that 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.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
* 02110-1301, USA.
*/
#include <linux/file.h>
#include <linux/fs.h>
#include <linux/linkage.h>
#include <linux/mm.h>
#include <linux/module.h>
#include <linux/sched.h>
#include <linux/slab.h>
#include <linux/syscalls.h>
#include <linux/unistd.h>
#include <asm/mman.h>
#include <asm/registers.h>
/*
* System calls with architecture-specific wrappers.
* See signal.c for signal-related system call wrappers.
*/
asmlinkage int sys_execve(char __user *ufilename,
const char __user *const __user *argv,
const char __user *const __user *envp)
{
struct pt_regs *pregs = current_thread_info()->regs;
struct filename *filename;
int retval;
filename = getname(ufilename);
retval = PTR_ERR(filename);
if (IS_ERR(filename))
return retval;
retval = do_execve(filename->name, argv, envp, pregs);
putname(filename);
return retval;
}
asmlinkage int sys_clone(unsigned long clone_flags, unsigned long newsp,
unsigned long parent_tidp, unsigned long child_tidp)
{
struct pt_regs *pregs = current_thread_info()->regs;
if (!newsp)
newsp = pregs->SP;
return do_fork(clone_flags, newsp, pregs, 0, (int __user *)parent_tidp,
(int __user *)child_tidp);
}
/*
* Do a system call from the kernel, so as to have a proper pt_regs
* and recycle the sys_execvpe infrustructure.
*/
int kernel_execve(const char *filename,
const char *const argv[], const char *const envp[])
{
register unsigned long __a0 asm("r0") = (unsigned long) filename;
register unsigned long __a1 asm("r1") = (unsigned long) argv;
register unsigned long __a2 asm("r2") = (unsigned long) envp;
int retval;
__asm__ volatile(
" R6 = #%4;\n"
" trap0(#1);\n"
" %0 = R0;\n"
: "=r" (retval)
: "r" (__a0), "r" (__a1), "r" (__a2), "i" (__NR_execve)
);
return retval;
}