Commit a37d01ea authored by Al Viro's avatar Al Viro
Browse files

x86: switch save_v86_state() to unsafe_put_user() 



Signed-off-by: default avatarAl Viro <viro@zeniv.linux.org.uk>
parent 77f3c616

arch/x86/kernel/vm86_32.c

+30 −31
Original line number Diff line number Diff line
@@ -98,7 +98,6 @@ void save_v86_state(struct kernel_vm86_regs *regs, int retval) 
	struct task_struct *tsk = current;

	struct vm86plus_struct __user *user;

	struct vm86 *vm86 = current->thread.vm86;

	long err = 0;



	/*

	 * This gets called from entry.S with interrupts disabled, but
@@ -114,37 +113,30 @@ void save_v86_state(struct kernel_vm86_regs *regs, int retval) 
	set_flags(regs->pt.flags, VEFLAGS, X86_EFLAGS_VIF | vm86->veflags_mask);

	user = vm86->user_vm86;



	if (!access_ok(user, vm86->vm86plus.is_vm86pus ?

	if (!user_access_begin(user, vm86->vm86plus.is_vm86pus ?

		       sizeof(struct vm86plus_struct) :

		       sizeof(struct vm86_struct))) {

		pr_alert("could not access userspace vm86 info\n");

		do_exit(SIGSEGV);

	}



	put_user_try {

		put_user_ex(regs->pt.bx, &user->regs.ebx);

		put_user_ex(regs->pt.cx, &user->regs.ecx);

		put_user_ex(regs->pt.dx, &user->regs.edx);

		put_user_ex(regs->pt.si, &user->regs.esi);

		put_user_ex(regs->pt.di, &user->regs.edi);

		put_user_ex(regs->pt.bp, &user->regs.ebp);

		put_user_ex(regs->pt.ax, &user->regs.eax);

		put_user_ex(regs->pt.ip, &user->regs.eip);

		put_user_ex(regs->pt.cs, &user->regs.cs);

		put_user_ex(regs->pt.flags, &user->regs.eflags);

		put_user_ex(regs->pt.sp, &user->regs.esp);

		put_user_ex(regs->pt.ss, &user->regs.ss);

		put_user_ex(regs->es, &user->regs.es);

		put_user_ex(regs->ds, &user->regs.ds);

		put_user_ex(regs->fs, &user->regs.fs);

		put_user_ex(regs->gs, &user->regs.gs);



		put_user_ex(vm86->screen_bitmap, &user->screen_bitmap);

	} put_user_catch(err);

	if (err) {

		pr_alert("could not access userspace vm86 info\n");

		do_exit(SIGSEGV);

	}

		       sizeof(struct vm86_struct)))

		goto Efault;



	unsafe_put_user(regs->pt.bx, &user->regs.ebx, Efault_end);

	unsafe_put_user(regs->pt.cx, &user->regs.ecx, Efault_end);

	unsafe_put_user(regs->pt.dx, &user->regs.edx, Efault_end);

	unsafe_put_user(regs->pt.si, &user->regs.esi, Efault_end);

	unsafe_put_user(regs->pt.di, &user->regs.edi, Efault_end);

	unsafe_put_user(regs->pt.bp, &user->regs.ebp, Efault_end);

	unsafe_put_user(regs->pt.ax, &user->regs.eax, Efault_end);

	unsafe_put_user(regs->pt.ip, &user->regs.eip, Efault_end);

	unsafe_put_user(regs->pt.cs, &user->regs.cs, Efault_end);

	unsafe_put_user(regs->pt.flags, &user->regs.eflags, Efault_end);

	unsafe_put_user(regs->pt.sp, &user->regs.esp, Efault_end);

	unsafe_put_user(regs->pt.ss, &user->regs.ss, Efault_end);

	unsafe_put_user(regs->es, &user->regs.es, Efault_end);

	unsafe_put_user(regs->ds, &user->regs.ds, Efault_end);

	unsafe_put_user(regs->fs, &user->regs.fs, Efault_end);

	unsafe_put_user(regs->gs, &user->regs.gs, Efault_end);

	unsafe_put_user(vm86->screen_bitmap, &user->screen_bitmap, Efault_end);



	user_access_end();



	preempt_disable();

	tsk->thread.sp0 = vm86->saved_sp0;
@@ -159,6 +151,13 @@ void save_v86_state(struct kernel_vm86_regs *regs, int retval) 
	lazy_load_gs(vm86->regs32.gs);



	regs->pt.ax = retval;

	return;



Efault_end:

	user_access_end();

Efault:

	pr_alert("could not access userspace vm86 info\n");

	do_exit(SIGSEGV);

}



static void mark_screen_rdonly(struct mm_struct *mm)