From 37f3605e5e7af7de12aeb670c5b94e5a3c8dbf74 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig <hch@lst.de> Date: Sat, 21 Jan 2023 08:10:42 +0100 Subject: [PATCH] mm: reject vmap with VM_FLUSH_RESET_PERMS Patch series "cleanup vfree and vunmap". This little series untangles the vfree and vunmap code path a bit. This patch (of 10): VM_FLUSH_RESET_PERMS is just for use with vmalloc as it is tied to freeing the underlying pages. Link: https://lkml.kernel.org/r/20230121071051.1143058-1-hch@lst.de Link: https://lkml.kernel.org/r/20230121071051.1143058-2-hch@lst.de Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Uladzislau Rezki (Sony) <urezki@gmail.com> Reviewed-by: David Hildenbrand <david@redhat.com> Cc: Alexander Potapenko <glider@google.com> Cc: Andrey Konovalov <andreyknvl@gmail.com> Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Vincenzo Frascino <vincenzo.frascino@arm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> --- mm/vmalloc.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/mm/vmalloc.c b/mm/vmalloc.c index 428e0bee5c9c7..3f3cb48759665 100644 --- a/mm/vmalloc.c +++ b/mm/vmalloc.c @@ -2868,6 +2868,9 @@ void *vmap(struct page **pages, unsigned int count, might_sleep(); + if (WARN_ON_ONCE(flags & VM_FLUSH_RESET_PERMS)) + return NULL; + /* * Your top guard is someone else's bottom guard. Not having a top * guard compromises someone else's mappings too. -- 2.30.2