On 06/13/22 at 12:00pm, Uladzislau Rezki wrote:
> > vmalloc does not allocate a vm_struct for vm_map_ram() areas. That causes
> > us to deny usercopies from those areas. This affects XFS which uses
> > vm_map_ram() for its directories.
> >
> > Fix this by calling find_vmap_area() instead of find_vm_area().
> >
> > Fixes: 0aef499f3172 ("mm/usercopy: Detect vmalloc overruns")
> > Signed-off-by: Matthew Wilcox (Oracle) <willy@xxxxxxxxxxxxx>
> > ---
> > include/linux/vmalloc.h | 1 +
> > mm/usercopy.c | 8 +++++---
> > mm/vmalloc.c | 2 +-
> > 3 files changed, 7 insertions(+), 4 deletions(-)
> >
> > diff --git a/include/linux/vmalloc.h b/include/linux/vmalloc.h
> > index b159c2789961..096d48aa3437 100644
> > --- a/include/linux/vmalloc.h
> > +++ b/include/linux/vmalloc.h
> > @@ -215,6 +215,7 @@ extern struct vm_struct *__get_vm_area_caller(unsigned long size,
> > void free_vm_area(struct vm_struct *area);
> > extern struct vm_struct *remove_vm_area(const void *addr);
> > extern struct vm_struct *find_vm_area(const void *addr);
> > +struct vmap_area *find_vmap_area(unsigned long addr);
> Make it "extern" since it becomes globally visible?
extern is not suggested any more to add for function declaration in
header file, and removing it doesn't impact thing.
>
> --
> Uladzislau Rezki
>
