}
#endif /* CONFIG_ANON_VMA_NAME */
+static inline unsigned long get_current_mdwe(void)
+{
+ unsigned long ret = 0;
+
+ if (test_bit(MMF_HAS_MDWE, ¤t->mm->flags))
+ ret |= PR_MDWE_REFUSE_EXEC_GAIN;
+ if (test_bit(MMF_HAS_MDWE_NO_INHERIT, ¤t->mm->flags))
+ ret |= PR_MDWE_NO_INHERIT;
+
+ return ret;
+}
+
static inline int prctl_set_mdwe(unsigned long bits, unsigned long arg3,
unsigned long arg4, unsigned long arg5)
{
+ unsigned long current_bits;
+
if (arg3 || arg4 || arg5)
return -EINVAL;
- if (bits & ~(PR_MDWE_REFUSE_EXEC_GAIN))
+ if (bits & ~(PR_MDWE_REFUSE_EXEC_GAIN | PR_MDWE_NO_INHERIT))
+ return -EINVAL;
+
+ /* NO_INHERIT only makes sense with REFUSE_EXEC_GAIN */
+ if (bits & PR_MDWE_NO_INHERIT && !(bits & PR_MDWE_REFUSE_EXEC_GAIN))
return -EINVAL;
+ /* PARISC cannot allow mdwe as it needs writable stacks */
+ if (IS_ENABLED(CONFIG_PARISC))
+ return -EINVAL;
+
+ current_bits = get_current_mdwe();
+ if (current_bits && current_bits != bits)
+ return -EPERM; /* Cannot unset the flags */
+
+ if (bits & PR_MDWE_NO_INHERIT)
+ set_bit(MMF_HAS_MDWE_NO_INHERIT, ¤t->mm->flags);
if (bits & PR_MDWE_REFUSE_EXEC_GAIN)
set_bit(MMF_HAS_MDWE, ¤t->mm->flags);
- else if (test_bit(MMF_HAS_MDWE, ¤t->mm->flags))
- return -EPERM; /* Cannot unset the flag */
return 0;
}
{
if (arg2 || arg3 || arg4 || arg5)
return -EINVAL;
-
- return test_bit(MMF_HAS_MDWE, ¤t->mm->flags) ?
- PR_MDWE_REFUSE_EXEC_GAIN : 0;
+ return get_current_mdwe();
}
static int prctl_get_auxv(void __user *addr, unsigned long len)
else
return -EINVAL;
break;
- case PR_GET_AUXV:
- if (arg4 || arg5)
- return -EINVAL;
- error = prctl_get_auxv((void __user *)arg2, arg3);
- break;
default:
return -EINVAL;
}
case PR_SET_VMA:
error = prctl_set_vma(arg2, arg3, arg4, arg5);
break;
+ case PR_GET_AUXV:
+ if (arg4 || arg5)
+ return -EINVAL;
+ error = prctl_get_auxv((void __user *)arg2, arg3);
+ break;
#ifdef CONFIG_KSM
case PR_SET_MEMORY_MERGE:
if (arg3 || arg4 || arg5)