mirror of
https://github.com/AuxXxilium/linux_dsm_epyc7002.git
synced 2024-12-01 13:16:37 +07:00
44f5c4ced6
In my previous x86_64 thread fix, I forgot to initialize thread.arch.fs in arch_prctl. A process calling arch_prctl to set %fs would lose it on the next context switch. It also turns out that you can switch to a process which is in the process of exiting and which has lost its mm. In this case, it's worse than useless to try to call arch_prctl on the host process. Signed-off-by: Jeff Dike <jdike@linux.intel.com> Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
151 lines
3.8 KiB
C
151 lines
3.8 KiB
C
/*
|
|
* Copyright 2003 PathScale, Inc.
|
|
*
|
|
* Licensed under the GPL
|
|
*/
|
|
|
|
#include "linux/linkage.h"
|
|
#include "linux/slab.h"
|
|
#include "linux/shm.h"
|
|
#include "linux/utsname.h"
|
|
#include "linux/personality.h"
|
|
#include "asm/uaccess.h"
|
|
#define __FRAME_OFFSETS
|
|
#include "asm/ptrace.h"
|
|
#include "asm/unistd.h"
|
|
#include "asm/prctl.h" /* XXX This should get the constants from libc */
|
|
#include "choose-mode.h"
|
|
#include "kern.h"
|
|
#include "os.h"
|
|
|
|
asmlinkage long sys_uname64(struct new_utsname __user * name)
|
|
{
|
|
int err;
|
|
down_read(&uts_sem);
|
|
err = copy_to_user(name, utsname(), sizeof (*name));
|
|
up_read(&uts_sem);
|
|
if (personality(current->personality) == PER_LINUX32)
|
|
err |= copy_to_user(&name->machine, "i686", 5);
|
|
return err ? -EFAULT : 0;
|
|
}
|
|
|
|
#ifdef CONFIG_MODE_TT
|
|
extern long arch_prctl(int code, unsigned long addr);
|
|
|
|
static long arch_prctl_tt(int code, unsigned long addr)
|
|
{
|
|
unsigned long tmp;
|
|
long ret;
|
|
|
|
switch(code){
|
|
case ARCH_SET_GS:
|
|
case ARCH_SET_FS:
|
|
ret = arch_prctl(code, addr);
|
|
break;
|
|
case ARCH_GET_FS:
|
|
case ARCH_GET_GS:
|
|
ret = arch_prctl(code, (unsigned long) &tmp);
|
|
if(!ret)
|
|
ret = put_user(tmp, (long __user *)addr);
|
|
break;
|
|
default:
|
|
ret = -EINVAL;
|
|
break;
|
|
}
|
|
|
|
return(ret);
|
|
}
|
|
#endif
|
|
|
|
#ifdef CONFIG_MODE_SKAS
|
|
|
|
long arch_prctl_skas(struct task_struct *task, int code,
|
|
unsigned long __user *addr)
|
|
{
|
|
unsigned long *ptr = addr, tmp;
|
|
long ret;
|
|
int pid = task->mm->context.skas.id.u.pid;
|
|
|
|
/*
|
|
* With ARCH_SET_FS (and ARCH_SET_GS is treated similarly to
|
|
* be safe), we need to call arch_prctl on the host because
|
|
* setting %fs may result in something else happening (like a
|
|
* GDT or thread.fs being set instead). So, we let the host
|
|
* fiddle the registers and thread struct and restore the
|
|
* registers afterwards.
|
|
*
|
|
* So, the saved registers are stored to the process (this
|
|
* needed because a stub may have been the last thing to run),
|
|
* arch_prctl is run on the host, then the registers are read
|
|
* back.
|
|
*/
|
|
switch(code){
|
|
case ARCH_SET_FS:
|
|
case ARCH_SET_GS:
|
|
restore_registers(pid, ¤t->thread.regs.regs);
|
|
break;
|
|
case ARCH_GET_FS:
|
|
case ARCH_GET_GS:
|
|
/*
|
|
* With these two, we read to a local pointer and
|
|
* put_user it to the userspace pointer that we were
|
|
* given. If addr isn't valid (because it hasn't been
|
|
* faulted in or is just bogus), we want put_user to
|
|
* fault it in (or return -EFAULT) instead of having
|
|
* the host return -EFAULT.
|
|
*/
|
|
ptr = &tmp;
|
|
}
|
|
|
|
ret = os_arch_prctl(pid, code, ptr);
|
|
if(ret)
|
|
return ret;
|
|
|
|
switch(code){
|
|
case ARCH_SET_FS:
|
|
current->thread.arch.fs = (unsigned long) ptr;
|
|
save_registers(pid, ¤t->thread.regs.regs);
|
|
break;
|
|
case ARCH_SET_GS:
|
|
save_registers(pid, ¤t->thread.regs.regs);
|
|
break;
|
|
case ARCH_GET_FS:
|
|
ret = put_user(tmp, addr);
|
|
break;
|
|
case ARCH_GET_GS:
|
|
ret = put_user(tmp, addr);
|
|
break;
|
|
}
|
|
|
|
return ret;
|
|
}
|
|
#endif
|
|
|
|
long sys_arch_prctl(int code, unsigned long addr)
|
|
{
|
|
return CHOOSE_MODE_PROC(arch_prctl_tt, arch_prctl_skas, current, code,
|
|
(unsigned long __user *) addr);
|
|
}
|
|
|
|
long sys_clone(unsigned long clone_flags, unsigned long newsp,
|
|
void __user *parent_tid, void __user *child_tid)
|
|
{
|
|
long ret;
|
|
|
|
if (!newsp)
|
|
newsp = UPT_SP(¤t->thread.regs.regs);
|
|
current->thread.forking = 1;
|
|
ret = do_fork(clone_flags, newsp, ¤t->thread.regs, 0, parent_tid,
|
|
child_tid);
|
|
current->thread.forking = 0;
|
|
return ret;
|
|
}
|
|
|
|
void arch_switch_to_skas(struct task_struct *from, struct task_struct *to)
|
|
{
|
|
if((to->thread.arch.fs == 0) || (to->mm == NULL))
|
|
return;
|
|
|
|
arch_prctl_skas(to, ARCH_SET_FS, (void __user *) to->thread.arch.fs);
|
|
}
|