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Diffstat (limited to 'arch/x86/kernel/process_32.c')
-rw-r--r--arch/x86/kernel/process_32.c53
1 files changed, 32 insertions, 21 deletions
diff --git a/arch/x86/kernel/process_32.c b/arch/x86/kernel/process_32.c
index 1a1ae8edc40c..fec79ad85dc6 100644
--- a/arch/x86/kernel/process_32.c
+++ b/arch/x86/kernel/process_32.c
@@ -11,6 +11,7 @@
#include <stdarg.h>
+#include <linux/stackprotector.h>
#include <linux/cpu.h>
#include <linux/errno.h>
#include <linux/sched.h>
@@ -91,6 +92,15 @@ void cpu_idle(void)
{
int cpu = smp_processor_id();
+ /*
+ * If we're the non-boot CPU, nothing set the stack canary up
+ * for us. CPU0 already has it initialized but no harm in
+ * doing it again. This is a good place for updating it, as
+ * we wont ever return from this function (so the invalid
+ * canaries already on the stack wont ever trigger).
+ */
+ boot_init_stack_canary();
+
current_thread_info()->status |= TS_POLLING;
/* endless idle loop with no priority at all */
@@ -131,7 +141,7 @@ void __show_regs(struct pt_regs *regs, int all)
if (user_mode_vm(regs)) {
sp = regs->sp;
ss = regs->ss & 0xffff;
- savesegment(gs, gs);
+ gs = get_user_gs(regs);
} else {
sp = (unsigned long) (&regs->sp);
savesegment(ss, ss);
@@ -212,6 +222,7 @@ int kernel_thread(int (*fn)(void *), void *arg, unsigned long flags)
regs.ds = __USER_DS;
regs.es = __USER_DS;
regs.fs = __KERNEL_PERCPU;
+ regs.gs = __KERNEL_STACK_CANARY;
regs.orig_ax = -1;
regs.ip = (unsigned long) kernel_thread_helper;
regs.cs = __KERNEL_CS | get_kernel_rpl();
@@ -304,7 +315,7 @@ int copy_thread(int nr, unsigned long clone_flags, unsigned long sp,
p->thread.ip = (unsigned long) ret_from_fork;
- savesegment(gs, p->thread.gs);
+ task_user_gs(p) = get_user_gs(regs);
tsk = current;
if (unlikely(test_tsk_thread_flag(tsk, TIF_IO_BITMAP))) {
@@ -342,7 +353,7 @@ int copy_thread(int nr, unsigned long clone_flags, unsigned long sp,
void
start_thread(struct pt_regs *regs, unsigned long new_ip, unsigned long new_sp)
{
- __asm__("movl %0, %%gs" : : "r"(0));
+ set_user_gs(regs, 0);
regs->fs = 0;
set_fs(USER_DS);
regs->ds = __USER_DS;
@@ -539,7 +550,7 @@ __switch_to(struct task_struct *prev_p, struct task_struct *next_p)
* used %fs or %gs (it does not today), or if the kernel is
* running inside of a hypervisor layer.
*/
- savesegment(gs, prev->gs);
+ lazy_save_gs(prev->gs);
/*
* Load the per-thread Thread-Local Storage descriptor.
@@ -585,31 +596,31 @@ __switch_to(struct task_struct *prev_p, struct task_struct *next_p)
* Restore %gs if needed (which is common)
*/
if (prev->gs | next->gs)
- loadsegment(gs, next->gs);
+ lazy_load_gs(next->gs);
percpu_write(current_task, next_p);
return prev_p;
}
-asmlinkage int sys_fork(struct pt_regs regs)
+int sys_fork(struct pt_regs *regs)
{
- return do_fork(SIGCHLD, regs.sp, &regs, 0, NULL, NULL);
+ return do_fork(SIGCHLD, regs->sp, regs, 0, NULL, NULL);
}
-asmlinkage int sys_clone(struct pt_regs regs)
+int sys_clone(struct pt_regs *regs)
{
unsigned long clone_flags;
unsigned long newsp;
int __user *parent_tidptr, *child_tidptr;
- clone_flags = regs.bx;
- newsp = regs.cx;
- parent_tidptr = (int __user *)regs.dx;
- child_tidptr = (int __user *)regs.di;
+ clone_flags = regs->bx;
+ newsp = regs->cx;
+ parent_tidptr = (int __user *)regs->dx;
+ child_tidptr = (int __user *)regs->di;
if (!newsp)
- newsp = regs.sp;
- return do_fork(clone_flags, newsp, &regs, 0, parent_tidptr, child_tidptr);
+ newsp = regs->sp;
+ return do_fork(clone_flags, newsp, regs, 0, parent_tidptr, child_tidptr);
}
/*
@@ -622,27 +633,27 @@ asmlinkage int sys_clone(struct pt_regs regs)
* do not have enough call-clobbered registers to hold all
* the information you need.
*/
-asmlinkage int sys_vfork(struct pt_regs regs)
+int sys_vfork(struct pt_regs *regs)
{
- return do_fork(CLONE_VFORK | CLONE_VM | SIGCHLD, regs.sp, &regs, 0, NULL, NULL);
+ return do_fork(CLONE_VFORK | CLONE_VM | SIGCHLD, regs->sp, regs, 0, NULL, NULL);
}
/*
* sys_execve() executes a new program.
*/
-asmlinkage int sys_execve(struct pt_regs regs)
+int sys_execve(struct pt_regs *regs)
{
int error;
char *filename;
- filename = getname((char __user *) regs.bx);
+ filename = getname((char __user *) regs->bx);
error = PTR_ERR(filename);
if (IS_ERR(filename))
goto out;
error = do_execve(filename,
- (char __user * __user *) regs.cx,
- (char __user * __user *) regs.dx,
- &regs);
+ (char __user * __user *) regs->cx,
+ (char __user * __user *) regs->dx,
+ regs);
if (error == 0) {
/* Make sure we don't return using sysenter.. */
set_thread_flag(TIF_IRET);