From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 7F1037F7DA for ; Fri, 26 Apr 2024 04:01:29 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1714104089; cv=none; b=LG2P47eJ8fGFB0/7hDz9sfH0QE6nz5t/EDUVDPv11C9A5Y8hkuquRaNocYepI81DIv8K36lNaIbb3DmngiGQ6DZFafT/pBTCf2WXJgskUyfXXp2YWRKcqiAl9g6PB9kDFbRDbpps9h+TXXwyCeCSl/xCWCQAxqAuWtOSSDVpRcs= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1714104089; c=relaxed/simple; bh=oM692+WXHdsMHuBj6s3n6AhiqcVEpV5fiWakGpBpW4g=; h=Date:To:From:Subject:Message-Id; b=hvokfnPbwRx9+0bFLH40Z0s0m8CfB9Md7ty2ZSgoZ9PkRUqkEL/a1t0xhqPK+0oD5q1HfQcoGom6I+yIF3L9laNdMOyj8Ob++W7xDYQnEjQqq+5JrVCoesPOpv3crsatvKr8OcG4uhaoQQ1dZ2kioI5ZlvKVP4jAoUMuGsMU+Zk= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux-foundation.org header.i=@linux-foundation.org header.b=XKUbL6wh; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux-foundation.org header.i=@linux-foundation.org header.b="XKUbL6wh" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 559C9C113CD; Fri, 26 Apr 2024 04:01:29 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux-foundation.org; s=korg; t=1714104089; bh=oM692+WXHdsMHuBj6s3n6AhiqcVEpV5fiWakGpBpW4g=; h=Date:To:From:Subject:From; b=XKUbL6whvoB8mc6IVI7UpLa7axFg+jw1D8rC/b8vYdqonjOkOZQfZC+j7Y37QB28O Z3Zn0NqdxfsbBHdqxaO6fB0V8bmMTvcWhzi9LWkg6t5/acZE4Vjs5YvGMC9n5c5L8Z UBLNLbXnlXZYgllMCywJ1tktIcpmdmHE1fzi4wZA= Date: Thu, 25 Apr 2024 21:01:28 -0700 To: mm-commits@vger.kernel.org,tglx@linutronix.de,peterz@infradead.org,npiggin@gmail.com,naveen.n.rao@linux.ibm.com,mpe@ellerman.id.au,mingo@redhat.com,luto@kernel.org,Liam.Howlett@oracle.com,kirill.shutemov@linux.intel.com,keescook@chromium.org,James.Bottomley@HansenPartnership.com,hpa@zytor.com,guoren@kernel.org,deller@gmx.de,debug@rivosinc.com,dave.hansen@linux.intel.com,dan.j.williams@intel.com,christophe.leroy@csgroup.eu,broonie@kernel.org,bp@alien8.de,ast@kernel.org,aneesh.kumar@kernel.org,rick.p.edgecombe@intel.com,akpm@linux-foundation.org From: Andrew Morton Subject: [merged mm-stable] parisc-use-initializer-for-struct-vm_unmapped_area_info.patch removed from -mm tree Message-Id: <20240426040129.559C9C113CD@smtp.kernel.org> Precedence: bulk X-Mailing-List: mm-commits@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: The quilt patch titled Subject: parisc: use initializer for struct vm_unmapped_area_info has been removed from the -mm tree. Its filename was parisc-use-initializer-for-struct-vm_unmapped_area_info.patch This patch was dropped because it was merged into the mm-stable branch of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm ------------------------------------------------------ From: Rick Edgecombe Subject: parisc: use initializer for struct vm_unmapped_area_info Date: Mon, 25 Mar 2024 19:16:50 -0700 Future changes will need to add a new member to struct vm_unmapped_area_info. This would cause trouble for any call site that doesn't initialize the struct. Currently every caller sets each member manually, so if new members are added they will be uninitialized and the core code parsing the struct will see garbage in the new member. It could be possible to initialize the new member manually to 0 at each call site. This and a couple other options were discussed, and a working consensus (see links) was that in general the best way to accomplish this would be via static initialization with designated member initiators. Having some struct vm_unmapped_area_info instances not zero initialized will put those sites at risk of feeding garbage into vm_unmapped_area() if the convention is to zero initialize the struct and any new member addition misses a call site that initializes each member manually. It could be possible to leave the code mostly untouched, and just change the line: struct vm_unmapped_area_info info to: struct vm_unmapped_area_info info = {}; However, that would leave cleanup for the members that are manually set to zero, as it would no longer be required. So to be reduce the chance of bugs via uninitialized members, instead simply continue the process to initialize the struct this way tree wide. This will zero any unspecified members. Move the member initializers to the struct declaration when they are known at that time. Leave the members out that were manually initialized to zero, as this would be redundant for designated initializers. Link: https://lkml.kernel.org/r/20240326021656.202649-9-rick.p.edgecombe@intel.com Link: https://lore.kernel.org/lkml/202402280912.33AEE7A9CF@keescook/#t Link: https://lore.kernel.org/lkml/j7bfvig3gew3qruouxrh7z7ehjjafrgkbcmg6tcghhfh3rhmzi@wzlcoecgy5rs/ Signed-off-by: Rick Edgecombe Reviewed-by: Christophe Leroy Acked-by: Helge Deller Cc: "James E.J. Bottomley" Cc: Helge Deller Cc: Alexei Starovoitov Cc: Andy Lutomirski Cc: Aneesh Kumar K.V Cc: Borislav Petkov (AMD) Cc: Dan Williams Cc: Dave Hansen Cc: Deepak Gupta Cc: Guo Ren Cc: H. Peter Anvin (Intel) Cc: Ingo Molnar Cc: Kees Cook Cc: Kirill A. Shutemov Cc: Liam R. Howlett Cc: Mark Brown Cc: Michael Ellerman Cc: Naveen N. Rao Cc: Nicholas Piggin Cc: Peter Zijlstra Cc: Thomas Gleixner Signed-off-by: Andrew Morton --- arch/parisc/kernel/sys_parisc.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) --- a/arch/parisc/kernel/sys_parisc.c~parisc-use-initializer-for-struct-vm_unmapped_area_info +++ a/arch/parisc/kernel/sys_parisc.c @@ -104,7 +104,9 @@ static unsigned long arch_get_unmapped_a struct vm_area_struct *vma, *prev; unsigned long filp_pgoff; int do_color_align; - struct vm_unmapped_area_info info; + struct vm_unmapped_area_info info = { + .length = len + }; if (unlikely(len > TASK_SIZE)) return -ENOMEM; @@ -139,7 +141,6 @@ static unsigned long arch_get_unmapped_a return addr; } - info.length = len; info.align_mask = do_color_align ? (PAGE_MASK & (SHM_COLOUR - 1)) : 0; info.align_offset = shared_align_offset(filp_pgoff, pgoff); @@ -160,7 +161,6 @@ static unsigned long arch_get_unmapped_a */ } - info.flags = 0; info.low_limit = mm->mmap_base; info.high_limit = mmap_upper_limit(NULL); return vm_unmapped_area(&info); _ Patches currently in -mm which might be from rick.p.edgecombe@intel.com are