Am 09.10.20 um 17:14 schrieb Jason Gunthorpe:
On Fri, Oct 09, 2020 at 05:03:38PM +0200, Christian König wrote:
+/*
+ * Change backing file, only valid to use during initial VMA setup.
+ */
+void vma_set_file(struct vm_area_struct *vma, struct file *file)
+{
+ if (file)
+ get_file(file);
+
+ swap(vma->vm_file, file);
+
+ if (file)
+ fput(file);
+}
fput crashes when file is NULL so the error handling after
unmap_and_free_vma: can't handle this case, similarly vm_file can't be
NULL either.
So just simply:
swap(vma->vm_file, file);
get_file(vma->vm_file);
fput(file);
Will do?
I was considering this as well, yes.
Just let it crash if any of them are wrongly NULL.
Mhm, changing from anonymous to file backed or reverse is probably not
such a good idea.
So yes catching those problems early is probably the best approach we
could do.
Going to do this in v4 if nobody objects.
Regards,
Christian.
Jason
