On Sun, Jun 09, 2019 at 09:51:45PM -0400, Theodore Ts'o wrote: > On Wed, Apr 17, 2019 at 12:04:33PM -0700, Darrick J. Wong wrote: > > diff --git a/mm/memory.c b/mm/memory.c > > index ab650c21bccd..dfd5eba278d6 100644 > > --- a/mm/memory.c > > +++ b/mm/memory.c > > @@ -2149,6 +2149,9 @@ static vm_fault_t do_page_mkwrite(struct vm_fault *vmf) > > > > vmf->flags = FAULT_FLAG_WRITE|FAULT_FLAG_MKWRITE; > > > > + if (vmf->vma->vm_file && IS_IMMUTABLE(file_inode(vmf->vma->vm_file))) > > + return VM_FAULT_SIGBUS; > > + > > ret = vmf->vma->vm_ops->page_mkwrite(vmf); > > /* Restore original flags so that caller is not surprised */ > > vmf->flags = old_flags; > > Shouldn't this check be moved before the modification of vmf->flags? > It looks like do_page_mkwrite() isn't supposed to be returning with > vmf->flags modified, lest "the caller gets surprised". Yeah, I think that was a merge error during a rebase... :( Er ... if you're still planning to take this patch through your tree, can you move it to above the "vmf->flags = FAULT_FLAG_WRITE..." ? --D > - Ted
