+CC vma reviewers
On Wed, Aug 28, 2024 at 10:55:21PM GMT, jeffxu@xxxxxxxxxxxx wrote:
> From: Jeff Xu <jeffxu@xxxxxxxxxxxx>
>
> mmap(MAP_FIXED) should return EPERM when memory is sealed.
>
> Fixes: 4205a39e06da ("mm/munmap: replace can_modify_mm with can_modify_vma")
Thank you for the patch!
This Fixes: is wrong, the bug was added during Liam's rebasing of his munmap patch
set on mine.
> Signed-off-by: Jeff Xu <jeffxu@xxxxxxxxxxxx>
> ---
> mm/mmap.c | 5 ++++-
> 1 file changed, 4 insertions(+), 1 deletion(-)
>
> diff --git a/mm/mmap.c b/mm/mmap.c
> index 80d70ed099cf..0cd0c0ef03c7 100644
> --- a/mm/mmap.c
> +++ b/mm/mmap.c
> @@ -1386,7 +1386,10 @@ unsigned long mmap_region(struct file *file, unsigned long addr,
> mt_on_stack(mt_detach);
> mas_init(&mas_detach, &mt_detach, /* addr = */ 0);
> /* Prepare to unmap any existing mapping in the area */
> - if (vms_gather_munmap_vmas(&vms, &mas_detach))
> + error = vms_gather_munmap_vmas(&vms, &mas_detach);
> + if (error == -EPERM)
> + return -EPERM;
Not sure if it makes sense to special case this. We should probably deal with this inside
vms_gather_munmap_vmas and just pass through the error we get.
Otherwise LGTM. Liam?
(we should also squash this into the offending commit)
--
Pedro
