Merge branch 'akpm-current/current'

[karo-tx-linux.git] / mm / mprotect.c

diff --git a/mm/mprotect.c b/mm/mprotect.c
index 8eb7bb40dc40b6e8e89d05fbb7e05f8c836e05da..6ff5dfa65b33d8453f097c80bd21f352127ed185 100644 (file)
--- a/mm/mprotect.c
+++ b/mm/mprotect.c
@@ -160,9 +160,11 @@ static inline unsigned long change_pmd_range(struct vm_area_struct *vma,
                }
 
                if (pmd_trans_huge(*pmd) || pmd_devmap(*pmd)) {
-                       if (next - addr != HPAGE_PMD_SIZE)
+                       if (next - addr != HPAGE_PMD_SIZE) {
                                split_huge_pmd(vma, pmd, addr);
-                       else {
+                               if (pmd_none(*pmd))
+                                       continue;
+                       } else {
                                int nr_ptes = change_huge_pmd(vma, pmd, addr,
                                                newprot, prot_numa);
 
@@ -352,10 +354,12 @@ fail:
 SYSCALL_DEFINE3(mprotect, unsigned long, start, size_t, len,
                unsigned long, prot)
 {
-       unsigned long vm_flags, nstart, end, tmp, reqprot;
+       unsigned long nstart, end, tmp, reqprot;
        struct vm_area_struct *vma, *prev;
        int error = -EINVAL;
        const int grows = prot & (PROT_GROWSDOWN|PROT_GROWSUP);
+       const bool rier = (current->personality & READ_IMPLIES_EXEC) &&
+                               (prot & PROT_READ);
        prot &= ~(PROT_GROWSDOWN|PROT_GROWSUP);
        if (grows == (PROT_GROWSDOWN|PROT_GROWSUP)) /* can't be both */
                return -EINVAL;
@@ -372,13 +376,6 @@ SYSCALL_DEFINE3(mprotect, unsigned long, start, size_t, len,
                return -EINVAL;
 
        reqprot = prot;
-       /*
-        * Does the application expect PROT_READ to imply PROT_EXEC:
-        */
-       if ((prot & PROT_READ) && (current->personality & READ_IMPLIES_EXEC))
-               prot |= PROT_EXEC;
-
-       vm_flags = calc_vm_prot_bits(prot);
 
        down_write(&current->mm->mmap_sem);
 
@@ -412,7 +409,11 @@ SYSCALL_DEFINE3(mprotect, unsigned long, start, size_t, len,
 
                /* Here we know that vma->vm_start <= nstart < vma->vm_end. */
 
-               newflags = vm_flags;
+               /* Does the application expect PROT_READ to imply PROT_EXEC */
+               if (rier && (vma->vm_flags & VM_MAYEXEC))
+                       prot |= PROT_EXEC;
+
+               newflags = calc_vm_prot_bits(prot);
                newflags |= (vma->vm_flags & ~(VM_READ | VM_WRITE | VM_EXEC));
 
                /* newflags >> 4 shift VM_MAY% in place of VM_% */
@@ -443,6 +444,7 @@ SYSCALL_DEFINE3(mprotect, unsigned long, start, size_t, len,
                        error = -ENOMEM;
                        goto out;
                }
+               prot = reqprot;
        }
 out:
        up_write(&current->mm->mmap_sem);