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Diffstat (limited to 'arch/x86/kernel/vm86_32.c')
-rw-r--r--arch/x86/kernel/vm86_32.c46
1 files changed, 27 insertions, 19 deletions
diff --git a/arch/x86/kernel/vm86_32.c b/arch/x86/kernel/vm86_32.c
index e6c2b47ec261..bfa59b1400b9 100644
--- a/arch/x86/kernel/vm86_32.c
+++ b/arch/x86/kernel/vm86_32.c
@@ -44,6 +44,7 @@
#include <linux/ptrace.h>
#include <linux/audit.h>
#include <linux/stddef.h>
+#include <linux/slab.h>
#include <asm/uaccess.h>
#include <asm/io.h>
@@ -81,8 +82,8 @@
/*
* virtual flags (16 and 32-bit versions)
*/
-#define VFLAGS (*(unsigned short *)&(current->thread.v86flags))
-#define VEFLAGS (current->thread.v86flags)
+#define VFLAGS (*(unsigned short *)&(current->thread.vm86->v86flags))
+#define VEFLAGS (current->thread.vm86->v86flags)
#define set_flags(X, new, mask) \
((X) = ((X) & ~(mask)) | ((new) & (mask)))
@@ -96,6 +97,7 @@ struct pt_regs *save_v86_state(struct kernel_vm86_regs *regs)
struct pt_regs *ret;
struct task_struct *tsk = current;
struct vm86plus_struct __user *user;
+ struct vm86 *vm86 = current->thread.vm86;
long err = 0;
/*
@@ -105,12 +107,12 @@ struct pt_regs *save_v86_state(struct kernel_vm86_regs *regs)
*/
local_irq_enable();
- if (!tsk->thread.vm86_info) {
+ if (!vm86 || !vm86->vm86_info) {
pr_alert("no vm86_info: BAD\n");
do_exit(SIGSEGV);
}
- set_flags(regs->pt.flags, VEFLAGS, X86_EFLAGS_VIF | tsk->thread.v86mask);
- user = tsk->thread.vm86_info;
+ set_flags(regs->pt.flags, VEFLAGS, X86_EFLAGS_VIF | vm86->v86mask);
+ user = vm86->vm86_info;
if (!access_ok(VERIFY_WRITE, user, VMPI.is_vm86pus ?
sizeof(struct vm86plus_struct) :
@@ -137,7 +139,7 @@ struct pt_regs *save_v86_state(struct kernel_vm86_regs *regs)
put_user_ex(regs->fs, &user->regs.fs);
put_user_ex(regs->gs, &user->regs.gs);
- put_user_ex(tsk->thread.screen_bitmap, &user->screen_bitmap);
+ put_user_ex(vm86->screen_bitmap, &user->screen_bitmap);
} put_user_catch(err);
if (err) {
pr_alert("could not access userspace vm86_info\n");
@@ -145,10 +147,10 @@ struct pt_regs *save_v86_state(struct kernel_vm86_regs *regs)
}
tss = &per_cpu(cpu_tss, get_cpu());
- tsk->thread.sp0 = tsk->thread.saved_sp0;
+ tsk->thread.sp0 = vm86->saved_sp0;
tsk->thread.sysenter_cs = __KERNEL_CS;
load_sp0(tss, &tsk->thread);
- tsk->thread.saved_sp0 = 0;
+ vm86->saved_sp0 = 0;
put_cpu();
ret = KVM86->regs32;
@@ -242,9 +244,15 @@ static long do_sys_vm86(struct vm86plus_struct __user *v86, bool plus,
{
struct tss_struct *tss;
struct task_struct *tsk = current;
+ struct vm86 *vm86 = tsk->thread.vm86;
unsigned long err = 0;
- if (tsk->thread.saved_sp0)
+ if (!vm86) {
+ if (!(vm86 = kzalloc(sizeof(*vm86), GFP_KERNEL)))
+ return -ENOMEM;
+ tsk->thread.vm86 = vm86;
+ }
+ if (vm86->saved_sp0)
return -EPERM;
if (!access_ok(VERIFY_READ, v86, plus ?
@@ -295,7 +303,7 @@ static long do_sys_vm86(struct vm86plus_struct __user *v86, bool plus,
}
info->regs32 = current_pt_regs();
- tsk->thread.vm86_info = v86;
+ vm86->vm86_info = v86;
/*
* The flags register is also special: we cannot trust that the user
@@ -311,16 +319,16 @@ static long do_sys_vm86(struct vm86plus_struct __user *v86, bool plus,
switch (info->cpu_type) {
case CPU_286:
- tsk->thread.v86mask = 0;
+ vm86->v86mask = 0;
break;
case CPU_386:
- tsk->thread.v86mask = X86_EFLAGS_NT | X86_EFLAGS_IOPL;
+ vm86->v86mask = X86_EFLAGS_NT | X86_EFLAGS_IOPL;
break;
case CPU_486:
- tsk->thread.v86mask = X86_EFLAGS_AC | X86_EFLAGS_NT | X86_EFLAGS_IOPL;
+ vm86->v86mask = X86_EFLAGS_AC | X86_EFLAGS_NT | X86_EFLAGS_IOPL;
break;
default:
- tsk->thread.v86mask = X86_EFLAGS_ID | X86_EFLAGS_AC | X86_EFLAGS_NT | X86_EFLAGS_IOPL;
+ vm86->v86mask = X86_EFLAGS_ID | X86_EFLAGS_AC | X86_EFLAGS_NT | X86_EFLAGS_IOPL;
break;
}
@@ -328,7 +336,7 @@ static long do_sys_vm86(struct vm86plus_struct __user *v86, bool plus,
* Save old state, set default return value (%ax) to 0 (VM86_SIGNAL)
*/
info->regs32->ax = VM86_SIGNAL;
- tsk->thread.saved_sp0 = tsk->thread.sp0;
+ vm86->saved_sp0 = tsk->thread.sp0;
lazy_save_gs(info->regs32->gs);
tss = &per_cpu(cpu_tss, get_cpu());
@@ -338,7 +346,7 @@ static long do_sys_vm86(struct vm86plus_struct __user *v86, bool plus,
load_sp0(tss, &tsk->thread);
put_cpu();
- tsk->thread.screen_bitmap = info->screen_bitmap;
+ vm86->screen_bitmap = info->screen_bitmap;
if (info->flags & VM86_SCREEN_BITMAP)
mark_screen_rdonly(tsk->mm);
@@ -408,7 +416,7 @@ static inline void clear_AC(struct kernel_vm86_regs *regs)
static inline void set_vflags_long(unsigned long flags, struct kernel_vm86_regs *regs)
{
- set_flags(VEFLAGS, flags, current->thread.v86mask);
+ set_flags(VEFLAGS, flags, current->thread.vm86->v86mask);
set_flags(regs->pt.flags, flags, SAFE_MASK);
if (flags & X86_EFLAGS_IF)
set_IF(regs);
@@ -418,7 +426,7 @@ static inline void set_vflags_long(unsigned long flags, struct kernel_vm86_regs
static inline void set_vflags_short(unsigned short flags, struct kernel_vm86_regs *regs)
{
- set_flags(VFLAGS, flags, current->thread.v86mask);
+ set_flags(VFLAGS, flags, current->thread.vm86->v86mask);
set_flags(regs->pt.flags, flags, SAFE_MASK);
if (flags & X86_EFLAGS_IF)
set_IF(regs);
@@ -433,7 +441,7 @@ static inline unsigned long get_vflags(struct kernel_vm86_regs *regs)
if (VEFLAGS & X86_EFLAGS_VIF)
flags |= X86_EFLAGS_IF;
flags |= X86_EFLAGS_IOPL;
- return flags | (VEFLAGS & current->thread.v86mask);
+ return flags | (VEFLAGS & current->thread.vm86->v86mask);
}
static inline int is_revectored(int nr, struct revectored_struct *bitmap)
generated by cgit v1.2.3 (git 2.39.0) at 2024-11-09 01:03:02 +0300