Jeff... come on now. Please cc- the reviewers of mm/mmap.c on these patches - that's me, Vlastimil and Liam. Same for mm/vma.c, mm/vma.h, mm/vma_internal.h. And it seems like it should be pretty obvious you should cc- Liam when it's quite literally his code you're changing! Relevant section from MAINTAINERS: MEMORY MAPPING M: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> R: Liam R. Howlett <Liam.Howlett@xxxxxxxxxx> R: Vlastimil Babka <vbabka@xxxxxxx> R: Lorenzo Stoakes <lorenzo.stoakes@xxxxxxxxxx> L: linux-mm@xxxxxxxxx S: Maintained W: http://www.linux-mm.org T: git git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm F: mm/mmap.c 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") > 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; > + if (error) > return -ENOMEM; Can't we just return the error here? This is one for Liam, but I'm ostensibly in favour, this does seem valid! > > vmg.next = vms.next; > -- > 2.46.0.295.g3b9ea8a38a-goog >