diff options
| -rw-r--r-- | security/selinux/selinuxfs.c | 44 | ||||
| -rw-r--r-- | security/selinux/ss/services.c | 2 |
2 files changed, 45 insertions, 1 deletions
diff --git a/security/selinux/selinuxfs.c b/security/selinux/selinuxfs.c index 8eb102c7260..87e0556bae7 100644 --- a/security/selinux/selinuxfs.c +++ b/security/selinux/selinuxfs.c @@ -439,9 +439,53 @@ out: return ret; } +static int sel_mmap_policy_fault(struct vm_area_struct *vma, + struct vm_fault *vmf) +{ + struct policy_load_memory *plm = vma->vm_file->private_data; + unsigned long offset; + struct page *page; + + if (vmf->flags & (FAULT_FLAG_MKWRITE | FAULT_FLAG_WRITE)) + return VM_FAULT_SIGBUS; + + offset = vmf->pgoff << PAGE_SHIFT; + if (offset >= roundup(plm->len, PAGE_SIZE)) + return VM_FAULT_SIGBUS; + + page = vmalloc_to_page(plm->data + offset); + get_page(page); + + vmf->page = page; + + return 0; +} + +static struct vm_operations_struct sel_mmap_policy_ops = { + .fault = sel_mmap_policy_fault, + .page_mkwrite = sel_mmap_policy_fault, +}; + +int sel_mmap_policy(struct file *filp, struct vm_area_struct *vma) +{ + if (vma->vm_flags & VM_SHARED) { + /* do not allow mprotect to make mapping writable */ + vma->vm_flags &= ~VM_MAYWRITE; + + if (vma->vm_flags & VM_WRITE) + return -EACCES; + } + + vma->vm_flags |= VM_RESERVED; + vma->vm_ops = &sel_mmap_policy_ops; + + return 0; +} + static const struct file_operations sel_policy_ops = { .open = sel_open_policy, .read = sel_read_policy, + .mmap = sel_mmap_policy, .release = sel_release_policy, }; diff --git a/security/selinux/ss/services.c b/security/selinux/ss/services.c index 7565d16aac3..3a1739b33b7 100644 --- a/security/selinux/ss/services.c +++ b/security/selinux/ss/services.c @@ -3169,7 +3169,7 @@ int security_read_policy(void **data, ssize_t *len) *len = security_policydb_len(); - *data = vmalloc(*len); + *data = vmalloc_user(*len); if (!*data) return -ENOMEM; |