tizen: Use unique directory prefix for baselibs packages

[platform/kernel/linux-rpi.git] / kernel / sys.c

diff --git a/kernel/sys.c b/kernel/sys.c
index 2410e39..7a4ae6d 100644 (file)
--- a/kernel/sys.c
+++ b/kernel/sys.c
@@ -2368,19 +2368,45 @@ static int prctl_set_vma(unsigned long opt, unsigned long start,
 }
 #endif /* CONFIG_ANON_VMA_NAME */
 
+static inline unsigned long get_current_mdwe(void)
+{
+       unsigned long ret = 0;
+
+       if (test_bit(MMF_HAS_MDWE, &current->mm->flags))
+               ret |= PR_MDWE_REFUSE_EXEC_GAIN;
+       if (test_bit(MMF_HAS_MDWE_NO_INHERIT, &current->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, &current->mm->flags);
        if (bits & PR_MDWE_REFUSE_EXEC_GAIN)
                set_bit(MMF_HAS_MDWE, &current->mm->flags);
-       else if (test_bit(MMF_HAS_MDWE, &current->mm->flags))
-               return -EPERM; /* Cannot unset the flag */
 
        return 0;
 }
@@ -2390,9 +2416,7 @@ static inline int prctl_get_mdwe(unsigned long arg2, unsigned long arg3,
 {
        if (arg2 || arg3 || arg4 || arg5)
                return -EINVAL;
-
-       return test_bit(MMF_HAS_MDWE, &current->mm->flags) ?
-               PR_MDWE_REFUSE_EXEC_GAIN : 0;
+       return get_current_mdwe();
 }
 
 static int prctl_get_auxv(void __user *addr, unsigned long len)