diff options
| -rw-r--r-- | drivers/staging/android/ashmem.c | 11 |
1 files changed, 10 insertions, 1 deletions
diff --git a/drivers/staging/android/ashmem.c b/drivers/staging/android/ashmem.c index 6f1a0bbc9a5..0b923b01da5 100644 --- a/drivers/staging/android/ashmem.c +++ b/drivers/staging/android/ashmem.c @@ -236,6 +236,13 @@ out: return ret; } +static inline unsigned long +calc_vm_may_flags(unsigned long prot) +{ + return _calc_vm_trans(prot, PROT_READ, VM_MAYREAD ) | + _calc_vm_trans(prot, PROT_WRITE, VM_MAYWRITE) | + _calc_vm_trans(prot, PROT_EXEC, VM_MAYEXEC); +} static int ashmem_mmap(struct file *file, struct vm_area_struct *vma) { @@ -251,10 +258,12 @@ static int ashmem_mmap(struct file *file, struct vm_area_struct *vma) } /* requested protection bits must match our allowed protection mask */ - if (unlikely((vma->vm_flags & ~asma->prot_mask) & PROT_MASK)) { + if (unlikely((vma->vm_flags & ~calc_vm_prot_bits(asma->prot_mask)) & + calc_vm_prot_bits(PROT_MASK))) { ret = -EPERM; goto out; } + vma->vm_flags &= ~calc_vm_may_flags(~asma->prot_mask); if (!asma->file) { char *name = ASHMEM_NAME_DEF; |