From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.io!.POSTED.blaine.gmane.org!not-for-mail From: Eli Zaretskii Newsgroups: gmane.emacs.devel Subject: Re: feature/asan-gc-poisoning aa9ca2c1493 2/2: src/alloc.c: Fix incorrect pointer arithmetic. Date: Mon, 05 Dec 2022 15:06:39 +0200 Message-ID: <83r0xe80f4.fsf@gnu.org> References: <167017421615.20730.5839006885061308371@vcs2.savannah.gnu.org> <20221204171657.3636BC00B0F@vcs2.savannah.gnu.org> <87k036ps88.fsf@yahoo.com> Injection-Info: ciao.gmane.io; posting-host="blaine.gmane.org:116.202.254.214"; logging-data="11586"; mail-complaints-to="usenet@ciao.gmane.io" Cc: emacs-devel@gnu.org, vibhavp@gmail.com To: Po Lu Original-X-From: emacs-devel-bounces+ged-emacs-devel=m.gmane-mx.org@gnu.org Mon Dec 05 14:08:59 2022 Return-path: Envelope-to: ged-emacs-devel@m.gmane-mx.org Original-Received: from lists.gnu.org ([209.51.188.17]) by ciao.gmane.io with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1p2BDP-0002lO-Dm for ged-emacs-devel@m.gmane-mx.org; Mon, 05 Dec 2022 14:08:59 +0100 Original-Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1p2BBs-0001nl-JG; Mon, 05 Dec 2022 08:07:24 -0500 Original-Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1p2BBS-0001d8-4d for emacs-devel@gnu.org; Mon, 05 Dec 2022 08:07:00 -0500 Original-Received: from fencepost.gnu.org ([2001:470:142:3::e]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1p2BBP-0003MP-W5; Mon, 05 Dec 2022 08:06:56 -0500 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=gnu.org; s=fencepost-gnu-org; h=References:Subject:In-Reply-To:To:From:Date: mime-version; bh=Gm9r4pI8/KIzVrVq2D/Rryj7ugo8NgFCsLxU1g0s9RE=; b=dQBiX4wu1vhx WZYbcIdI+bMWqzpNVPEH5Ev/IBGhq/jSoP8ye2H1MggiIvrmH0I70ttimB2ooZ3hblH76yw7+oIH7 T/fScNcpl8451TnwI2XFhzOdmzZL8u2zZNiMGwBo4LjSBLS/QvlY0yGVd1wB2Rbbf8OY0vM6QZ0M4 rWLmZKzB/lZ8hksu2e9UDDMKyiZr8+B+jueoEm2Njey5P9JQFQxRMDgHlZKIcgDUwfJBOc2N7K22h 2m6KpNNKD4o5N8zM2OcGNix28qY5l7xQ27U92Q3pV2KxufNv4QO6aa4IAGd9zIC2XOMZ9AGHgR4If 0YLbeFV66exPjv6YQ+JLFA==; Original-Received: from [87.69.77.57] (helo=home-c4e4a596f7) by fencepost.gnu.org with esmtpsa (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1p2BBO-0005Ez-Rh; Mon, 05 Dec 2022 08:06:55 -0500 In-Reply-To: <87k036ps88.fsf@yahoo.com> (message from Po Lu on Mon, 05 Dec 2022 09:13:59 +0800) X-BeenThere: emacs-devel@gnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: "Emacs development discussions." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: emacs-devel-bounces+ged-emacs-devel=m.gmane-mx.org@gnu.org Original-Sender: emacs-devel-bounces+ged-emacs-devel=m.gmane-mx.org@gnu.org Xref: news.gmane.io gmane.emacs.devel:300927 Archived-At: > From: Po Lu > Cc: Vibhav Pant > Date: Mon, 05 Dec 2022 09:13:59 +0800 > > Vibhav Pant writes: > > > branch: feature/asan-gc-poisoning > > commit aa9ca2c1493f1cd9d50698747fd054b1be53dc95 > > Author: Vibhav Pant > > Commit: Vibhav Pant > > > > src/alloc.c: Fix incorrect pointer arithmetic. > > > > * src/alloc.c (live_float_holding): Use parenthesis around the > > pointer arithmetic expression to untag 'cp' correctly. > > --- > > src/alloc.c | 2 +- > > 1 file changed, 1 insertion(+), 1 deletion(-) > > > > diff --git a/src/alloc.c b/src/alloc.c > > index 31108837e5a..6b8a4cdcc02 100644 > > --- a/src/alloc.c > > +++ b/src/alloc.c > > @@ -5104,7 +5104,7 @@ live_float_holding (struct mem_node *m, void *p) > > && (b != float_block > > || offset / sizeof b->floats[0] < float_block_index)) > > { > > - struct Lisp_Float *f = (struct Lisp_Float *) cp - off; > > + struct Lisp_Float *f = (struct Lisp_Float *) (cp - off); > > #if GC_ASAN_POISON_OBJECTS > > if (__asan_region_is_poisoned (f, sizeof (*f))) > > return NULL; > > This is a problem on master and emacs-29 too, right? I don't think so: there are no such code on those two branches, AFAICT.