From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 6C72CCF64B1 for ; Sat, 22 Nov 2025 04:51:42 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 450F06B0010; Fri, 21 Nov 2025 23:51:41 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id 401326B0011; Fri, 21 Nov 2025 23:51:41 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 2EFA06B0012; Fri, 21 Nov 2025 23:51:41 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0011.hostedemail.com [216.40.44.11]) by kanga.kvack.org (Postfix) with ESMTP id 19E8A6B0010 for ; Fri, 21 Nov 2025 23:51:41 -0500 (EST) Received: from smtpin28.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay07.hostedemail.com (Postfix) with ESMTP id 632C41607C0 for ; Sat, 22 Nov 2025 04:51:39 +0000 (UTC) X-FDA: 84137019918.28.0752773 Received: from relay.hostedemail.com (unirelay07 [10.200.18.70]) by imf24.hostedemail.com (Postfix) with ESMTP id A0B15180007 for ; Sat, 22 Nov 2025 04:51:37 +0000 (UTC) Authentication-Results: imf24.hostedemail.com; none ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1763787097; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=lb5XVyTevFRmZ3WNn7e33CY5XsENhkQmd79+UQ0qfZk=; b=moaeZbk63KzEBm36BZTkiiElxlNlGnjfCl5UxU6Jurz5Jxvr39xySyHItwXX+n2rQyIPXL OqzdVXe22usz47yRhFAp03EcjzTF48xzoqvhAoAPRqIGLxMePOIe75xwjNUNvzoR/p2vEg 7ycc4coJOzEkqC+VqTm0C2mKqW2/KzM= ARC-Authentication-Results: i=1; imf24.hostedemail.com; none ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1763787097; a=rsa-sha256; cv=none; b=OmjJXNFFfpSA8MQF41W2/0Hp4OZpA3irf+pZ+pZz9PVxJL+/J5JRXL/emVuQJom6B1Rtac oUBhuVhxf46KNHJGpR27TKSP5469w7PeedmHHW7OW4ueWLCjOSPne8AhSajDr+hkfpm/wz MPLjQY3PILjsMEaMi7tGF2jFo5P7fe8= Received: from omf14.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay07.hostedemail.com (Postfix) with ESMTP id A5B841607B4; Sat, 22 Nov 2025 04:51:33 +0000 (UTC) Received: from [HIDDEN] (Authenticated sender: joe@perches.com) by omf14.hostedemail.com (Postfix) with ESMTPA id C6BA130; Sat, 22 Nov 2025 04:51:20 +0000 (UTC) Message-ID: Subject: Re: [PATCH v5 3/4] checkpatch: Suggest kmalloc_obj family for sizeof allocations From: Joe Perches To: Kees Cook , Vlastimil Babka Cc: Andy Whitcroft , Dwaipayan Ray , Lukas Bulwahn , Randy Dunlap , Miguel Ojeda , Przemek Kitszel , "Gustavo A. R. Silva" , Linus Torvalds , Matthew Wilcox , Christoph Lameter , Marco Elver , Vegard Nossum , Pekka Enberg , David Rientjes , Joonsoo Kim , Andrew Morton , Roman Gushchin , Harry Yoo , Bill Wendling , Justin Stitt , Jann Horn , Greg Kroah-Hartman , Sasha Levin , linux-mm@kvack.org, Nathan Chancellor , Peter Zijlstra , Nick Desaulniers , Jonathan Corbet , Jakub Kicinski , Yafang Shao , Tony Ambardar , Alexander Lobakin , Jan Hendrik Farr , Alexander Potapenko , linux-kernel@vger.kernel.org, linux-hardening@vger.kernel.org, linux-doc@vger.kernel.org, llvm@lists.linux.dev Date: Fri, 21 Nov 2025 20:51:19 -0800 In-Reply-To: <20251122014304.3417954-3-kees@kernel.org> References: <20251122014258.do.018-kees@kernel.org> <20251122014304.3417954-3-kees@kernel.org> Content-Type: text/plain; charset="ISO-8859-1" Content-Transfer-Encoding: quoted-printable User-Agent: Evolution 3.56.2 (3.56.2-2.fc42) MIME-Version: 1.0 X-Session-Marker: 6A6F6540706572636865732E636F6D X-Session-ID: U2FsdGVkX1+Sr1JQ+437w6kkX38ORxtyNSi2FQhscRU= X-HE-Meta: U2FsdGVkX1+M0hbju6B4R0TNwI2E2iep66FeX6Que0tNsb+p8wMZ25hWgq/0Vg70NWm4auf2lfTvdpVhLVnfB1hBlf5wFSevwBSyC6wNObgGWMSG0iH9DzDUrYTNDo1mwj53A3UlpMDs/Z2ciaydLxUjMSIkc3wYa0yAFskiGr3Tq2v2v12WwDKOLviXDa9mthgm8+7cSFMGd5Waqo5a6wL6Mgv1Le1Mknb+2EzvfPlMA8grKHD5zYIb6mFlNhPbNWs5Ml0iBRYXn8u6C5HyT5LVyPiZlIL+x5IRaAH/Pm0+Q/OzWQjOGYlSjR+teOoC X-Rspamd-Queue-Id: A0B15180007 X-Stat-Signature: y1e6wye49h55e9yihtz99bqq8wccka44 X-Rspamd-Server: rspam02 X-HE-Tag-Orig: 1763787080-150056 X-Rspam-User: X-HE-Tag: 1763787097-316547 X-HE-Meta: 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 jVtESHEF 2Ehl37RahGk4cRGiGvRC/itdoTa6WAHdD5eHhv9OousxoCoYA1AGLVktmwg== X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Fri, 2025-11-21 at 17:42 -0800, Kees Cook wrote: > To support shifting away from sized allocation towards typed > allocations, suggest the kmalloc_obj family of macros when a sizeof() is > present in the argument lists. [] > diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl [] > @@ -7258,17 +7258,42 @@ sub process { > "Prefer $3(sizeof(*$1)...) over $3($4...)\n" . $herecurr); > } > =20 > -# check for (kv|k)[mz]alloc with multiplies that could be kmalloc_array/= kvmalloc_array/kvcalloc/kcalloc > +# check for (kv|k)[mz]alloc that could be kmalloc_obj/kvmalloc_obj/kzall= oc_obj/kvzalloc_obj There are _way_ too many of these existing uses to suggest this change in existing files so please add '&& !$file' to these tests > + if ($perl_version_ok && > + defined $stat && > + $stat =3D~ /^\+\s*($Lval)\s*\=3D\s*(?:$balanced_parens)?\s*((?:kv|= k)[mz]alloc)\s*\(\s*($FuncArg)\s*,/) { > + my $oldfunc =3D $3; > + my $a1 =3D $4; > + my $newfunc =3D "kmalloc_obj"; > + $newfunc =3D "kvmalloc_obj" if ($oldfunc eq "kvmalloc"); > + $newfunc =3D "kvzalloc_obj" if ($oldfunc eq "kvzalloc"); > + $newfunc =3D "kzalloc_obj" if ($oldfunc eq "kzalloc"); > + > + if ($a1 =3D~ s/^sizeof\s*\S\(?([^\)]*)\)?$/$1/) { > + my $cnt =3D statement_rawlines($stat); > + my $herectx =3D get_stat_here($linenr, $cnt, $here); > + > + if (WARN("ALLOC_WITH_SIZEOF", > + "Prefer $newfunc over $oldfunc with sizeof\n" . $herectx) && > + $cnt =3D=3D 1 && > + $fix) { > + $fixed[$fixlinenr] =3D~ s/\b($Lval)\s*\=3D\s*(?:$balanced_parens)?\= s*((?:kv|k)[mz]alloc)\s*\(\s*($FuncArg)\s*,/$1 =3D $newfunc($a1,/; > + } > + } > + } > + > + > +# check for (kv|k)[mz]alloc with multiplies that could be kmalloc_objs/k= vmalloc_objs/kzalloc_objs/kvzalloc_objs > if ($perl_version_ok && > defined $stat && > $stat =3D~ /^\+\s*($Lval)\s*\=3D\s*(?:$balanced_parens)?\s*((?:kv|= k)[mz]alloc)\s*\(\s*($FuncArg)\s*\*\s*($FuncArg)\s*,/) { > my $oldfunc =3D $3; > my $a1 =3D $4; > my $a2 =3D $10; > - my $newfunc =3D "kmalloc_array"; > - $newfunc =3D "kvmalloc_array" if ($oldfunc eq "kvmalloc"); > - $newfunc =3D "kvcalloc" if ($oldfunc eq "kvzalloc"); > - $newfunc =3D "kcalloc" if ($oldfunc eq "kzalloc"); > + my $newfunc =3D "kmalloc_objs"; > + $newfunc =3D "kvmalloc_objs" if ($oldfunc eq "kvmalloc"); > + $newfunc =3D "kvzalloc_objs" if ($oldfunc eq "kvzalloc"); > + $newfunc =3D "kzalloc_objs" if ($oldfunc eq "kzalloc"); > my $r1 =3D $a1; > my $r2 =3D $a2; > if ($a1 =3D~ /^sizeof\s*\S/) { > @@ -7284,7 +7309,9 @@ sub process { > "Prefer $newfunc over $oldfunc with multiply\n" . $herectx) && > $cnt =3D=3D 1 && > $fix) { > - $fixed[$fixlinenr] =3D~ s/\b($Lval)\s*\=3D\s*(?:$balanced_parens)?\= s*((?:kv|k)[mz]alloc)\s*\(\s*($FuncArg)\s*\*\s*($FuncArg)/$1 . ' =3D ' . "$= newfunc(" . trim($r1) . ', ' . trim($r2)/e; > + my $sized =3D trim($r2); > + $sized =3D~ s/^sizeof\s*\S\(?([^\)]*)\)?$/$1/; > + $fixed[$fixlinenr] =3D~ s/\b($Lval)\s*\=3D\s*(?:$balanced_parens)?\= s*((?:kv|k)[mz]alloc)\s*\(\s*($FuncArg)\s*\*\s*($FuncArg)/$1 . ' =3D ' . "$= newfunc(" . $sized . ', ' . trim($r1)/e; > } > } > }