diff --git a/mm/nommu.c b/mm/nommu.c index 28754c40be98..4bde489ec431 100644 --- a/mm/nommu.c +++ b/mm/nommu.c @@ -919,6 +919,10 @@ static int validate_mmap_request(struct file *file, if (!file->f_op->read) capabilities &= ~BDI_CAP_MAP_COPY; + /* The file shall have been opened with read permission. */ + if (!(file->f_mode & FMODE_READ)) + return -EACCES; + if (flags & MAP_SHARED) { /* do checks for writing, appending and locking */ if ((prot & PROT_WRITE) &&