From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp-out2.suse.de (smtp-out2.suse.de [195.135.223.131]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 68CDC18FC75 for ; Mon, 28 Oct 2024 21:00:14 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=195.135.223.131 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1730149216; cv=none; b=pfeM0PkGzcY7uz/9bU88WaUgsTEymyaR04FiKO/emHYvXhgEYCkTEqfAexZ67daZuZ3SSlh79FqcMoQVMtM1vOPhOkGMAuef7zVJWFwdFvhfFG11zRJ/ZsDVndsr41vc+bEN0bFFwXbThb/nKOG2kGPFmeTZzIzDUcA3WAerUg8= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1730149216; c=relaxed/simple; bh=2R9Sh0GU1SqjsYYszRTrwU7rR4sj6b3HH41bb/a5a+Y=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=QgASeMCvOTkAy4T0CwgrYwCuFW//7+n36myBoeTlNd2dCTHJVAlRriqp/W+SOLGuLKs6jvFWKtDSY40Ne8DFnwiOWmNVI+hcV1viRPMU3v96vs5Uy93KzG0Ehgr41nMnIDqTVbr0a4G5ylJ/+IVJYrzTyEzQ0sdSnPTCODV4NUA= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=suse.cz; spf=pass smtp.mailfrom=suse.cz; dkim=pass (1024-bit key) header.d=suse.cz header.i=@suse.cz header.b=FQrsIqMB; dkim=permerror (0-bit key) header.d=suse.cz header.i=@suse.cz header.b=MPB0AEQh; dkim=pass (1024-bit key) header.d=suse.cz header.i=@suse.cz header.b=WkTgtwGx; dkim=permerror (0-bit key) header.d=suse.cz header.i=@suse.cz header.b=o/eeHX7Y; arc=none smtp.client-ip=195.135.223.131 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=suse.cz Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=suse.cz Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=suse.cz header.i=@suse.cz header.b="FQrsIqMB"; dkim=permerror (0-bit key) header.d=suse.cz header.i=@suse.cz header.b="MPB0AEQh"; dkim=pass (1024-bit key) header.d=suse.cz header.i=@suse.cz header.b="WkTgtwGx"; dkim=permerror (0-bit key) header.d=suse.cz header.i=@suse.cz header.b="o/eeHX7Y" Received: from imap1.dmz-prg2.suse.org (unknown [10.150.64.97]) (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 94D911FDB4; Mon, 28 Oct 2024 21:00:05 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.cz; s=susede2_rsa; t=1730149206; h=from:from:reply-to: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:autocrypt:autocrypt; bh=MIu8nbphfr0kRpJXu0L3XhSe06h41uBB4XXp8vIsjxU=; b=FQrsIqMBVP10UOIMfQvrX+aobJcjBh7NVYsyW41hVX9BmQ+//g5HdDepr0L2CwIac1AH2s 4BEaojhyk2KZ4p9im60xvzurEd9dyD5W8hldNl/V9e6VcwDwxdwPsGMOlQgmpdSTFDlZw6 5JNIuKMMGkY2vgjRR6+5JWDxmk2/wkU= DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=suse.cz; s=susede2_ed25519; t=1730149206; h=from:from:reply-to: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:autocrypt:autocrypt; bh=MIu8nbphfr0kRpJXu0L3XhSe06h41uBB4XXp8vIsjxU=; b=MPB0AEQhutVquFsbMPAPyr4KT05AUMlM06orXwlKpxm7r5ftfbhFTIpCZBwWxYi8bh4eFl rRPqTg19sGNodGCw== Authentication-Results: smtp-out2.suse.de; none DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.cz; s=susede2_rsa; t=1730149205; h=from:from:reply-to: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:autocrypt:autocrypt; bh=MIu8nbphfr0kRpJXu0L3XhSe06h41uBB4XXp8vIsjxU=; b=WkTgtwGxafHo3jqf8s0DkgSAtYnyWxW9Po1ya/Q+HPeSMaSryT7B0l55Czayr1A7sKfZbD NsAXUMCFKJcMm4N2hnqxCwwis/eTTxBgJfTJvs6VAsSFQwKCu6p11wZ2FqcdUDk5ii+wmH dWZA13rE+weuIwA7gVr4VSfAZnne9QE= DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=suse.cz; s=susede2_ed25519; t=1730149205; h=from:from:reply-to: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:autocrypt:autocrypt; bh=MIu8nbphfr0kRpJXu0L3XhSe06h41uBB4XXp8vIsjxU=; b=o/eeHX7YK1XUT6/NSl54j2oHJBm1I27JN02FaM2tXuEjtXKo21efrTp4andrnl5/3p181s srA3iv17R1Z/1CCg== Received: from imap1.dmz-prg2.suse.org (localhost [127.0.0.1]) (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 imap1.dmz-prg2.suse.org (Postfix) with ESMTPS id 76F1D136DC; Mon, 28 Oct 2024 21:00:05 +0000 (UTC) Received: from dovecot-director2.suse.de ([2a07:de40:b281:106:10:150:64:167]) by imap1.dmz-prg2.suse.org with ESMTPSA id 2ImzHFX7H2c+agAAD6G6ig (envelope-from ); Mon, 28 Oct 2024 21:00:05 +0000 Message-ID: <0b64edb9-491e-4dcd-8dc1-d3c8a336a49b@suse.cz> Date: Mon, 28 Oct 2024 22:00:05 +0100 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH hotfix 6.12 v2 4/8] mm: resolve faulty mmap_region() error path behaviour Content-Language: en-US To: Linus Torvalds , Lorenzo Stoakes Cc: "Liam R. Howlett" , Mark Brown , Andrew Morton , Jann Horn , linux-kernel@vger.kernel.org, linux-mm@kvack.org, Peter Xu , linux-arm-kernel@lists.infradead.org, Catalin Marinas , Will Deacon , Aishwarya TCV References: <6e8deda970b982e1e8ffd876e3cef342c292fbb5.1729715266.git.lorenzo.stoakes@oracle.com> <61461dcc-e455-450d-9c01-5465003fc31c@sirena.org.uk> <438f50c5-8b8c-444f-ae85-10e5151f3f24@lucifer.local> <57mgmdx7wgfwci3yo3ggkmcnm3ujamgkwcccm77ypvmer5tegn@opiq3ceh2uvy> From: Vlastimil Babka Autocrypt: addr=vbabka@suse.cz; keydata= xsFNBFZdmxYBEADsw/SiUSjB0dM+vSh95UkgcHjzEVBlby/Fg+g42O7LAEkCYXi/vvq31JTB KxRWDHX0R2tgpFDXHnzZcQywawu8eSq0LxzxFNYMvtB7sV1pxYwej2qx9B75qW2plBs+7+YB 87tMFA+u+L4Z5xAzIimfLD5EKC56kJ1CsXlM8S/LHcmdD9Ctkn3trYDNnat0eoAcfPIP2OZ+ 9oe9IF/R28zmh0ifLXyJQQz5ofdj4bPf8ecEW0rhcqHfTD8k4yK0xxt3xW+6Exqp9n9bydiy tcSAw/TahjW6yrA+6JhSBv1v2tIm+itQc073zjSX8OFL51qQVzRFr7H2UQG33lw2QrvHRXqD Ot7ViKam7v0Ho9wEWiQOOZlHItOOXFphWb2yq3nzrKe45oWoSgkxKb97MVsQ+q2SYjJRBBH4 8qKhphADYxkIP6yut/eaj9ImvRUZZRi0DTc8xfnvHGTjKbJzC2xpFcY0DQbZzuwsIZ8OPJCc LM4S7mT25NE5kUTG/TKQCk922vRdGVMoLA7dIQrgXnRXtyT61sg8PG4wcfOnuWf8577aXP1x 6mzw3/jh3F+oSBHb/GcLC7mvWreJifUL2gEdssGfXhGWBo6zLS3qhgtwjay0Jl+kza1lo+Cv BB2T79D4WGdDuVa4eOrQ02TxqGN7G0Biz5ZLRSFzQSQwLn8fbwARAQABzSBWbGFzdGltaWwg QmFia2EgPHZiYWJrYUBzdXNlLmN6PsLBlAQTAQoAPgIbAwULCQgHAwUVCgkICwUWAgMBAAIe AQIXgBYhBKlA1DSZLC6OmRA9UCJPp+fMgqZkBQJkBREIBQkRadznAAoJECJPp+fMgqZkNxIQ ALZRqwdUGzqL2aeSavbum/VF/+td+nZfuH0xeWiO2w8mG0+nPd5j9ujYeHcUP1edE7uQrjOC Gs9sm8+W1xYnbClMJTsXiAV88D2btFUdU1mCXURAL9wWZ8Jsmz5ZH2V6AUszvNezsS/VIT87 AmTtj31TLDGwdxaZTSYLwAOOOtyqafOEq+gJB30RxTRE3h3G1zpO7OM9K6ysLdAlwAGYWgJJ V4JqGsQ/lyEtxxFpUCjb5Pztp7cQxhlkil0oBYHkudiG8j1U3DG8iC6rnB4yJaLphKx57NuQ PIY0Bccg+r9gIQ4XeSK2PQhdXdy3UWBr913ZQ9AI2usid3s5vabo4iBvpJNFLgUmxFnr73SJ KsRh/2OBsg1XXF/wRQGBO9vRuJUAbnaIVcmGOUogdBVS9Sun/Sy4GNA++KtFZK95U7J417/J Hub2xV6Ehc7UGW6fIvIQmzJ3zaTEfuriU1P8ayfddrAgZb25JnOW7L1zdYL8rXiezOyYZ8Fm ZyXjzWdO0RpxcUEp6GsJr11Bc4F3aae9OZtwtLL/jxc7y6pUugB00PodgnQ6CMcfR/HjXlae h2VS3zl9+tQWHu6s1R58t5BuMS2FNA58wU/IazImc/ZQA+slDBfhRDGYlExjg19UXWe/gMcl De3P1kxYPgZdGE2eZpRLIbt+rYnqQKy8UxlszsBNBFsZNTUBCACfQfpSsWJZyi+SHoRdVyX5 J6rI7okc4+b571a7RXD5UhS9dlVRVVAtrU9ANSLqPTQKGVxHrqD39XSw8hxK61pw8p90pg4G /N3iuWEvyt+t0SxDDkClnGsDyRhlUyEWYFEoBrrCizbmahOUwqkJbNMfzj5Y7n7OIJOxNRkB IBOjPdF26dMP69BwePQao1M8Acrrex9sAHYjQGyVmReRjVEtv9iG4DoTsnIR3amKVk6si4Ea X/mrapJqSCcBUVYUFH8M7bsm4CSxier5ofy8jTEa/CfvkqpKThTMCQPNZKY7hke5qEq1CBk2 wxhX48ZrJEFf1v3NuV3OimgsF2odzieNABEBAAHCwXwEGAEKACYCGwwWIQSpQNQ0mSwujpkQ PVAiT6fnzIKmZAUCZAUSmwUJDK5EZgAKCRAiT6fnzIKmZOJGEACOKABgo9wJXsbWhGWYO7mD 8R8mUyJHqbvaz+yTLnvRwfe/VwafFfDMx5GYVYzMY9TWpA8psFTKTUIIQmx2scYsRBUwm5VI EurRWKqENcDRjyo+ol59j0FViYysjQQeobXBDDE31t5SBg++veI6tXfpco/UiKEsDswL1WAr tEAZaruo7254TyH+gydURl2wJuzo/aZ7Y7PpqaODbYv727Dvm5eX64HCyyAH0s6sOCyGF5/p eIhrOn24oBf67KtdAN3H9JoFNUVTYJc1VJU3R1JtVdgwEdr+NEciEfYl0O19VpLE/PZxP4wX PWnhf5WjdoNI1Xec+RcJ5p/pSel0jnvBX8L2cmniYnmI883NhtGZsEWj++wyKiS4NranDFlA HdDM3b4lUth1pTtABKQ1YuTvehj7EfoWD3bv9kuGZGPrAeFNiHPdOT7DaXKeHpW9homgtBxj 8aX/UkSvEGJKUEbFL9cVa5tzyialGkSiZJNkWgeHe+jEcfRT6pJZOJidSCdzvJpbdJmm+eED w9XOLH1IIWh7RURU7G1iOfEfmImFeC3cbbS73LQEFGe1urxvIH5K/7vX+FkNcr9ujwWuPE9b 1C2o4i/yZPLXIVy387EjA6GZMqvQUFuSTs/GeBcv0NjIQi8867H3uLjz+mQy63fAitsDwLmR EP+ylKVEKb0Q2A== In-Reply-To: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-Spam-Score: -4.29 X-Spamd-Result: default: False [-4.29 / 50.00]; BAYES_HAM(-3.00)[100.00%]; NEURAL_HAM_LONG(-1.00)[-1.000]; NEURAL_HAM_SHORT(-0.19)[-0.932]; MIME_GOOD(-0.10)[text/plain]; MID_RHS_MATCH_FROM(0.00)[]; RCVD_VIA_SMTP_AUTH(0.00)[]; MIME_TRACE(0.00)[0:+]; ARC_NA(0.00)[]; RCPT_COUNT_TWELVE(0.00)[13]; RCVD_TLS_ALL(0.00)[]; DKIM_SIGNED(0.00)[suse.cz:s=susede2_rsa,suse.cz:s=susede2_ed25519]; FUZZY_BLOCKED(0.00)[rspamd.com]; FROM_HAS_DN(0.00)[]; TO_DN_SOME(0.00)[]; FROM_EQ_ENVFROM(0.00)[]; TO_MATCH_ENVRCPT_ALL(0.00)[]; RCVD_COUNT_TWO(0.00)[2]; DBL_BLOCKED_OPENRESOLVER(0.00)[oracle.com:email] X-Spam-Flag: NO X-Spam-Level: On 10/28/24 21:22, Linus Torvalds wrote: > On Mon, 28 Oct 2024 at 10:18, Lorenzo Stoakes > wrote: >> >> I'm genuinely not opposed to a horrible, awful: >> >> #ifdef CONFIG_ARM64 >> if (file && file->f_ops == shmem_file_operations) >> vm_flags |= VM_MTE_ALLOWED; >> #endif >> >> Early in the operation prior to the arch_validate_flags() check. > > I would just put it inside the arm64 code itself. > > IOW, get rid of the VM_MTE_ALLOWED flag entirely, and just make the > arm64 arch_validate_flags() code do something like > > if (flags & VM_MTE) { > if (file->f_ops != shmem_file_operations) > return false; > } > > and be done with it. VM_MTE_ALLOWED is also set by arm64's arch_calc_vm_flag_bits(): if (system_supports_mte() && (flags & MAP_ANONYMOUS)) return VM_MTE_ALLOWED; And there's also this in arch/arm64/include/asm/page.h #define VM_DATA_DEFAULT_FLAGS (VM_DATA_FLAGS_TSK_EXEC | VM_MTE_ALLOWED) So it would need to all be considered in the validation if we wanted to replace VM_MTE_ALLOWED completely? > Considering that we only have that horrendous arch_validate_flags() > for two architectures, and that they both just have magical special > cases for MTE-like behavior, I do think that just making it be a hack > inside those functions is the way to go. > > Linus