futex_atomic_op_inuser (int encoded_op, u32 __user *uaddr)
{
unsigned long int flags;
- u32 val;
int op = (encoded_op >> 28) & 7;
int cmp = (encoded_op >> 24) & 15;
int oparg = (encoded_op << 8) >> 20;
int cmparg = (encoded_op << 20) >> 20;
- int oldval = 0, ret;
+ int oldval, ret;
+ u32 tmp;
+
if (encoded_op & (FUTEX_OP_OPARG_SHIFT << 28))
oparg = 1 << oparg;
if (!access_ok(VERIFY_WRITE, uaddr, sizeof(*uaddr)))
return -EFAULT;
+ _futex_spin_lock_irqsave(uaddr, &flags);
pagefault_disable();
- _futex_spin_lock_irqsave(uaddr, &flags);
+ ret = -EFAULT;
+ if (unlikely(get_user(oldval, uaddr) != 0))
+ goto out_pagefault_enable;
+
+ ret = 0;
+ tmp = oldval;
switch (op) {
case FUTEX_OP_SET:
- /* *(int *)UADDR2 = OPARG; */
- ret = get_user(oldval, uaddr);
- if (!ret)
- ret = put_user(oparg, uaddr);
+ tmp = oparg;
break;
case FUTEX_OP_ADD:
- /* *(int *)UADDR2 += OPARG; */
- ret = get_user(oldval, uaddr);
- if (!ret) {
- val = oldval + oparg;
- ret = put_user(val, uaddr);
- }
+ tmp += oparg;
break;
case FUTEX_OP_OR:
- /* *(int *)UADDR2 |= OPARG; */
- ret = get_user(oldval, uaddr);
- if (!ret) {
- val = oldval | oparg;
- ret = put_user(val, uaddr);
- }
+ tmp |= oparg;
break;
case FUTEX_OP_ANDN:
- /* *(int *)UADDR2 &= ~OPARG; */
- ret = get_user(oldval, uaddr);
- if (!ret) {
- val = oldval & ~oparg;
- ret = put_user(val, uaddr);
- }
+ tmp &= ~oparg;
break;
case FUTEX_OP_XOR:
- /* *(int *)UADDR2 ^= OPARG; */
- ret = get_user(oldval, uaddr);
- if (!ret) {
- val = oldval ^ oparg;
- ret = put_user(val, uaddr);
- }
+ tmp ^= oparg;
break;
default:
ret = -ENOSYS;
}
- _futex_spin_unlock_irqrestore(uaddr, &flags);
+ if (ret == 0 && unlikely(put_user(tmp, uaddr) != 0))
+ ret = -EFAULT;
+out_pagefault_enable:
pagefault_enable();
+ _futex_spin_unlock_irqrestore(uaddr, &flags);
- if (!ret) {
+ if (ret == 0) {
switch (cmp) {
case FUTEX_OP_CMP_EQ: ret = (oldval == cmparg); break;
case FUTEX_OP_CMP_NE: ret = (oldval != cmparg); break;
return ret;
}
-/* Non-atomic version */
static inline int
futex_atomic_cmpxchg_inatomic(u32 *uval, u32 __user *uaddr,
u32 oldval, u32 newval)
{
- int ret;
u32 val;
unsigned long flags;
*/
_futex_spin_lock_irqsave(uaddr, &flags);
+ if (unlikely(get_user(val, uaddr) != 0)) {
+ _futex_spin_unlock_irqrestore(uaddr, &flags);
+ return -EFAULT;
+ }
- ret = get_user(val, uaddr);
-
- if (!ret && val == oldval)
- ret = put_user(newval, uaddr);
+ if (val == oldval && unlikely(put_user(newval, uaddr) != 0)) {
+ _futex_spin_unlock_irqrestore(uaddr, &flags);
+ return -EFAULT;
+ }
*uval = val;
-
_futex_spin_unlock_irqrestore(uaddr, &flags);
- return ret;
+ return 0;
}
#endif /*__KERNEL__*/