From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-io0-f199.google.com (mail-io0-f199.google.com [209.85.223.199]) by kanga.kvack.org (Postfix) with ESMTP id 8A5046B0397 for ; Tue, 4 Apr 2017 17:10:05 -0400 (EDT) Received: by mail-io0-f199.google.com with SMTP id y22so71898253ioe.9 for ; Tue, 04 Apr 2017 14:10:05 -0700 (PDT) Received: from mail-it0-x234.google.com (mail-it0-x234.google.com. [2607:f8b0:4001:c0b::234]) by mx.google.com with ESMTPS id b130si15675807itb.21.2017.04.04.14.10.04 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Tue, 04 Apr 2017 14:10:04 -0700 (PDT) Received: by mail-it0-x234.google.com with SMTP id y18so68083045itc.1 for ; Tue, 04 Apr 2017 14:10:04 -0700 (PDT) MIME-Version: 1.0 In-Reply-To: <1491340140-18238-1-git-send-email-labbott@redhat.com> References: <1491340140-18238-1-git-send-email-labbott@redhat.com> From: Kees Cook Date: Tue, 4 Apr 2017 14:10:03 -0700 Message-ID: Subject: Re: [PATCH] mm/usercopy: Drop extra is_vmalloc_or_module check Content-Type: text/plain; charset=UTF-8 Sender: owner-linux-mm@kvack.org List-ID: To: Laura Abbott Cc: Linux-MM , LKML , "linux-arm-kernel@lists.infradead.org" , Mark Rutland On Tue, Apr 4, 2017 at 2:09 PM, Laura Abbott wrote: > virt_addr_valid was previously insufficient to validate if virt_to_page > could be called on an address on arm64. This has since been fixed up > so there is no need for the extra check. Drop it. > > Signed-off-by: Laura Abbott > --- > I've given this some testing on my machine and haven't seen any problems > (e.g. random crashes without the check) and the fix has been in for long > enough now. I'm in no rush to have this merged so I'm okay if this sits in > a tree somewhere to get more testing. Awesome, thanks! I'll get it into my usercopy branch for -next. -Kees > --- > mm/usercopy.c | 11 ----------- > 1 file changed, 11 deletions(-) > > diff --git a/mm/usercopy.c b/mm/usercopy.c > index d155e12563b1..4d23a0e0e232 100644 > --- a/mm/usercopy.c > +++ b/mm/usercopy.c > @@ -206,17 +206,6 @@ static inline const char *check_heap_object(const void *ptr, unsigned long n, > { > struct page *page; > > - /* > - * Some architectures (arm64) return true for virt_addr_valid() on > - * vmalloced addresses. Work around this by checking for vmalloc > - * first. > - * > - * We also need to check for module addresses explicitly since we > - * may copy static data from modules to userspace > - */ > - if (is_vmalloc_or_module_addr(ptr)) > - return NULL; > - > if (!virt_addr_valid(ptr)) > return NULL; > > -- > 2.12.1 > -- Kees Cook Pixel Security -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org