From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from smtp-out2.suse.de (smtp-out2.suse.de [195.135.223.131]) by sourceware.org (Postfix) with ESMTPS id 4693F3858410 for ; Fri, 22 Mar 2024 08:08:27 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.2 sourceware.org 4693F3858410 Authentication-Results: sourceware.org; dmarc=pass (p=none dis=none) header.from=suse.de Authentication-Results: sourceware.org; spf=pass smtp.mailfrom=suse.de ARC-Filter: OpenARC Filter v1.0.0 sourceware.org 4693F3858410 Authentication-Results: server2.sourceware.org; arc=none smtp.remote-ip=195.135.223.131 ARC-Seal: i=1; a=rsa-sha256; d=sourceware.org; s=key; t=1711094917; cv=none; b=rmSZn3nPOY22XlVm7vAJzQW7X0lQ6anStS17j3cPOONzav96EylGfFSQKFdKIMW5+wZqlwEZXBZIC9TN9Zr39Pqw39Cn3zd86R6W7c3Btr8tvCfyuGjQPxsUSzgq0+PMkNLO9M8H5O2D2WW43vyT2EIi6geDOacunB1Nk1S1vJM= ARC-Message-Signature: i=1; a=rsa-sha256; d=sourceware.org; s=key; t=1711094917; c=relaxed/simple; bh=XiK6KpY/BC46A1cZTlmCsjaRp20RwroZECFHMQpLFyE=; h=DKIM-Signature:DKIM-Signature:DKIM-Signature:DKIM-Signature:Date: From:To:Subject:Message-ID:MIME-Version; b=sMQgfMwIGc8VnYiZVZ6BdmNbZ2ImY0hZQ4VQf7c0AOliFJ8GK2CEX+xwMajUoc7b83rEUJ+FOyY05M1f7vl91wiSboS4L5N95bv4ycmzA9/IRB0SYwNy2WbWGxCRJQ523oDTTT35fELqaBGK56m9DAN2FUyYszYwqngGHL3tFyY= ARC-Authentication-Results: i=1; server2.sourceware.org Received: from [10.168.4.150] (unknown [10.168.4.150]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) by smtp-out2.suse.de (Postfix) with ESMTPS id 051835FB5A; Fri, 22 Mar 2024 08:08:24 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.de; s=susede2_rsa; t=1711094906; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=Z+QdX7Ntut0QIHuCrxd7NH+ujuW/ynJTKQc3ojbPwgE=; b=LfkcSemkUauIFsUH/taov4yn0YYSz538AHdDoFZH5tRHtSqyois3cXUVZOfH7EQBbZkuEY 1DENOSuXxJz2JCSuAeUP/v6f+aw5hOO1j6qpf/Pe81/H5dw3JaWb3sejjSfWymdGkslCFP mau2BxaqNZ1Au1jNreDhyo6VHumV4aM= DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=suse.de; s=susede2_ed25519; t=1711094906; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=Z+QdX7Ntut0QIHuCrxd7NH+ujuW/ynJTKQc3ojbPwgE=; b=6VsG5ZWN/ipYtYn4OBxzs68347SfF8s/+5O6jFlEfe97Gcchw6rAUwsGrJYO4AAPlPLtvr 8/wx34Dmq60RIgCQ== DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.de; s=susede2_rsa; t=1711094904; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=Z+QdX7Ntut0QIHuCrxd7NH+ujuW/ynJTKQc3ojbPwgE=; b=p4YIFfZR4brvpbQCmPYI9CzW+d+c/VD/SsnpvG1LPNxZ1xl++Z95t3cErLn8i4q870A65h +bIiJ/vGLu72TNq8QVb+yAa/ciJ8KDIwdYlrrlZecaVWJn35B4a3K7csF5niHGYDHkqrR5 Y4BMW+FwyVT+P8dIYPR7fKqkDC8nTLA= DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=suse.de; s=susede2_ed25519; t=1711094904; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=Z+QdX7Ntut0QIHuCrxd7NH+ujuW/ynJTKQc3ojbPwgE=; b=abEhNwuh0qrDb8YxsuNM8iWEm/8l9H7d5kwITgbBbwCd9wGx6arwfQYnm0dktHGGfGvYj7 SmxcqGq+E+7GqmAA== Date: Fri, 22 Mar 2024 09:08:23 +0100 (CET) From: Richard Biener To: Jakub Jelinek cc: gcc-patches@gcc.gnu.org Subject: Re: [PATCH] ubsan: Don't -fsanitize=null instrument __seg_fs/gs pointers [PR111736] In-Reply-To: Message-ID: References: MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII X-Spam-Score: -1.10 X-Spamd-Result: default: False [-1.10 / 50.00]; ARC_NA(0.00)[]; FROM_HAS_DN(0.00)[]; TO_DN_SOME(0.00)[]; TO_MATCH_ENVRCPT_ALL(0.00)[]; NEURAL_SPAM_SHORT(3.00)[1.000]; MIME_GOOD(-0.10)[text/plain]; NEURAL_HAM_LONG(-1.00)[-1.000]; DKIM_SIGNED(0.00)[suse.de:s=susede2_rsa,suse.de:s=susede2_ed25519]; RCPT_COUNT_TWO(0.00)[2]; DBL_BLOCKED_OPENRESOLVER(0.00)[suse.de:email,ubsan.cc:url]; FUZZY_BLOCKED(0.00)[rspamd.com]; RCVD_COUNT_ZERO(0.00)[0]; FROM_EQ_ENVFROM(0.00)[]; MIME_TRACE(0.00)[0:+]; BAYES_HAM(-3.00)[100.00%] X-Spam-Level: Authentication-Results: smtp-out2.suse.de; none X-Spam-Status: No, score=-4.9 required=5.0 tests=BAYES_00,DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,SPF_HELO_NONE,SPF_PASS,TXREP autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on server2.sourceware.org List-Id: On Fri, 22 Mar 2024, Jakub Jelinek wrote: > Hi! > > On x86 and avr some address spaces allow 0 pointers (on avr actually > even generic as, but libsanitizer isn't ported to it and > I'm not convinced we should completely kill -fsanitize=null in that > case). > The following patch makes sure those aren't diagnosed for -fsanitize=null, > though they are still sanitized for -fsanitize=alignment. > > Bootstrapped/regtested on x86_64-linux and i686-linux, ok for trunk? OK. > 2024-03-22 Jakub Jelinek > > PR sanitizer/111736 > * ubsan.cc (ubsan_expand_null_ifn, instrument_mem_ref): Avoid > SANITIZE_NULL instrumentation for non-generic address spaces > for which targetm.addr_space.zero_address_valid (as) is true. > > * gcc.dg/ubsan/pr111736.c: New test. > > --- gcc/ubsan.cc.jj 2024-03-13 09:16:37.791885010 +0100 > +++ gcc/ubsan.cc 2024-03-22 08:11:50.093131678 +0100 > @@ -858,6 +858,13 @@ ubsan_expand_null_ifn (gimple_stmt_itera > } > } > check_null = sanitize_flags_p (SANITIZE_NULL); > + if (check_null && POINTER_TYPE_P (TREE_TYPE (ptr))) > + { > + addr_space_t as = TYPE_ADDR_SPACE (TREE_TYPE (TREE_TYPE (ptr))); > + if (!ADDR_SPACE_GENERIC_P (as) > + && targetm.addr_space.zero_address_valid (as)) > + check_null = false; > + } > > if (check_align == NULL_TREE && !check_null) > { > @@ -1447,8 +1454,15 @@ instrument_mem_ref (tree mem, tree base, > if (align <= 1) > align = 0; > } > - if (align == 0 && !sanitize_flags_p (SANITIZE_NULL)) > - return; > + if (align == 0) > + { > + if (!sanitize_flags_p (SANITIZE_NULL)) > + return; > + addr_space_t as = TYPE_ADDR_SPACE (TREE_TYPE (base)); > + if (!ADDR_SPACE_GENERIC_P (as) > + && targetm.addr_space.zero_address_valid (as)) > + return; > + } > tree t = TREE_OPERAND (base, 0); > if (!POINTER_TYPE_P (TREE_TYPE (t))) > return; > --- gcc/testsuite/gcc.dg/ubsan/pr111736.c.jj 2024-03-21 13:50:49.482348296 +0100 > +++ gcc/testsuite/gcc.dg/ubsan/pr111736.c 2024-03-21 13:53:33.789091054 +0100 > @@ -0,0 +1,23 @@ > +/* PR sanitizer/111736 */ > +/* { dg-do compile { target i?86-*-* x86_64-*-* } } */ > +/* { dg-options "-fsanitize=null,alignment -fdump-tree-optimized -ffat-lto-objects" } */ > +/* { dg-final { scan-tree-dump-times "__ubsan_handle_type_mismatch" 1 "optimized" } } */ > +/* { dg-final { scan-tree-dump-not "p_\[0-9]*.D. \[=!]= 0" "optimized" } } */ > + > +#ifdef __x86_64__ > +#define SEG __seg_fs > +#else > +#define SEG __seg_gs > +#endif > + > +int > +foo (int SEG *p, int *q) > +{ > + return *p; > +} > + > +__attribute__((no_sanitize("alignment"))) int > +bar (int SEG *p, int *q) > +{ > + return *p; > +} > > Jakub > > -- Richard Biener SUSE Software Solutions Germany GmbH, Frankenstrasse 146, 90461 Nuernberg, Germany; GF: Ivo Totev, Andrew McDonald, Werner Knoblich; (HRB 36809, AG Nuernberg)