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 lists.zx2c4.com (lists.zx2c4.com [165.227.139.114]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 04C6CCA0FE2 for ; Thu, 21 Aug 2025 20:07:37 +0000 (UTC) Received: by lists.zx2c4.com (ZX2C4 Mail Server) with ESMTP id 988995e6; Thu, 21 Aug 2025 20:07:37 +0000 (UTC) Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) by lists.zx2c4.com (ZX2C4 Mail Server) with ESMTPS id 5e61e713 (TLSv1.3:TLS_AES_256_GCM_SHA384:256:NO) for ; Thu, 21 Aug 2025 20:07:33 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1755806852; h=from:from: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=A9Znt0atqEjtEUkbTSfKRsvBJ9rEcbnqI7Kn1XkJSrA=; b=ITLO/1J6W1DJKSfaKtRf06Ot+s9ohvdWvDpizjU2cvmrr4sGCrYfwaIORAQjCFcgOYMMoV wOrzYt8vDNcFokA/hnukRSSXVgMroYh7wkGw2kcY0IiZYu37GO0F2to9QtKhn7uo8rTU5A w2TNG2pR+567D24FAMyh8j/jvBts4VU= Received: from mail-wm1-f70.google.com (mail-wm1-f70.google.com [209.85.128.70]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-178-EJFJEWmFNVWs0K7hoI2t2g-1; Thu, 21 Aug 2025 16:07:28 -0400 X-MC-Unique: EJFJEWmFNVWs0K7hoI2t2g-1 X-Mimecast-MFC-AGG-ID: EJFJEWmFNVWs0K7hoI2t2g_1755806847 Received: by mail-wm1-f70.google.com with SMTP id 5b1f17b1804b1-45a1b0b2b5cso10135945e9.2 for ; Thu, 21 Aug 2025 13:07:28 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1755806847; x=1756411647; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=A9Znt0atqEjtEUkbTSfKRsvBJ9rEcbnqI7Kn1XkJSrA=; b=xVmxdxmE3W0hFd97YHcwxIBJcxLltB1VQFUUA2u/C3WldgXRQuy+Vgw/wLs1tI/KTZ uBhu36ShKnbxo/i+/2zOzpOzjGyAywXw0QTg0s+4XrUCJ0q7YNhgaOs3UeyoTAh+3n3w HQj+mVNFujEHPsmbgaubRBHc5gnsiEMSRag0t6ogZK2xUs0YM6REEAl/VxQgC3w59lzd EFB38YOXLJGjGrXGqtH/16nUllDtHT8CJwoG60ZsmpMQsr/STrDinu3G1muYzLgNTxZa 7wW2zxR/LE4G/r0+5E6KFs6aniZwkpi5/abTrrsC1S3qoAZh2K71aQSyT1+rljhwiKfO 9hCQ== X-Forwarded-Encrypted: i=1; AJvYcCUG0n5iy+9jWKAVdA1VmQ5ve0uD5lJr/VKigipi32apHS7wNRhUnUJqKggdtRXTl1eI/SscH3FAbwY=@lists.zx2c4.com X-Gm-Message-State: AOJu0Yzs3nF8i4odH6Oz/DOFmHpd0lnUUzevXYp8fBLUOus0Z316vBWJ b5y4gX/+kmmpd2buT3v69RZYsRzhIc4Pm4p1k7hae0LPiM4+fEBx0v+ZWECzmQACFtEwHM2ByBd YBLloRQ0XcnH5ogU0AN9J93xsJRfod8V042PpUjPs/CmyiFlft4aJy1WXaZZeBw== X-Gm-Gg: ASbGncuChr1sM2V5at3cQo9OEnYq1tV5dtH+CoTlZnhEzknV1J4MtvN+M36Cx4FAGB2 FNovKRmmepO2VfGBbM51rV1PujGyWjdvUEySW/MipVGQxTh2FsalZ874f4NSveyNlLj8EAyeGT9 rsr40WuZhw4/c3H74VRcgjP8XL09s5ezOhKIv0GpJEYUlq/zcYf4BRmcoUG9y7uOgn36KwLheI5 cxc4AgLtcaZO5cYnCv68oBiCgucgQ0MPOERtnI9gPVyGCWe3zlgnouVnwNQfe7qRG/zuiwpp4GE AsSOtfqrNmGIr9dm78aItpYZiaAamK+v+M0//ETcLyBkjp2+NYrzQgthV48MX2diveAbu9rrJiJ qnv9zSf8krnAcPfpZiovApQ== X-Received: by 2002:a05:600c:3552:b0:459:dde3:1a33 with SMTP id 5b1f17b1804b1-45b517d26d4mr2922165e9.26.1755806847219; Thu, 21 Aug 2025 13:07:27 -0700 (PDT) X-Google-Smtp-Source: AGHT+IGUeapMM5JkcwJNJXC+LM6ICHu4lGUEF2ir46AAuHXhYXAFzTcPIdec/q/lplZD/isU7mGEgg== X-Received: by 2002:a05:600c:3552:b0:459:dde3:1a33 with SMTP id 5b1f17b1804b1-45b517d26d4mr2921795e9.26.1755806846742; Thu, 21 Aug 2025 13:07:26 -0700 (PDT) Received: from localhost (p200300d82f26ba0008036ec5991806fd.dip0.t-ipconnect.de. [2003:d8:2f26:ba00:803:6ec5:9918:6fd]) by smtp.gmail.com with UTF8SMTPSA id 5b1f17b1804b1-45b50d62991sm9535385e9.0.2025.08.21.13.07.24 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Thu, 21 Aug 2025 13:07:26 -0700 (PDT) From: David Hildenbrand To: linux-kernel@vger.kernel.org Cc: David Hildenbrand , Alexander Potapenko , Andrew Morton , Brendan Jackman , Christoph Lameter , Dennis Zhou , Dmitry Vyukov , dri-devel@lists.freedesktop.org, intel-gfx@lists.freedesktop.org, iommu@lists.linux.dev, io-uring@vger.kernel.org, Jason Gunthorpe , Jens Axboe , Johannes Weiner , John Hubbard , kasan-dev@googlegroups.com, kvm@vger.kernel.org, "Liam R. Howlett" , Linus Torvalds , linux-arm-kernel@axis.com, linux-arm-kernel@lists.infradead.org, linux-crypto@vger.kernel.org, linux-ide@vger.kernel.org, linux-kselftest@vger.kernel.org, linux-mips@vger.kernel.org, linux-mmc@vger.kernel.org, linux-mm@kvack.org, linux-riscv@lists.infradead.org, linux-s390@vger.kernel.org, linux-scsi@vger.kernel.org, Lorenzo Stoakes , Marco Elver , Marek Szyprowski , Michal Hocko , Mike Rapoport , Muchun Song , netdev@vger.kernel.org, Oscar Salvador , Peter Xu , Robin Murphy , Suren Baghdasaryan , Tejun Heo , virtualization@lists.linux.dev, Vlastimil Babka , wireguard@lists.zx2c4.com, x86@kernel.org, Zi Yan Subject: [PATCH RFC 07/35] mm/memremap: reject unreasonable folio/compound page sizes in memremap_pages() Date: Thu, 21 Aug 2025 22:06:33 +0200 Message-ID: <20250821200701.1329277-8-david@redhat.com> X-Mailer: git-send-email 2.50.1 In-Reply-To: <20250821200701.1329277-1-david@redhat.com> References: <20250821200701.1329277-1-david@redhat.com> MIME-Version: 1.0 X-Mimecast-Spam-Score: 0 X-Mimecast-MFC-PROC-ID: xZGTi7SCzfEdoEOH6vfMOxhmpnotCWmmeE24PQEKdmM_1755806847 X-Mimecast-Originator: redhat.com Content-Transfer-Encoding: 8bit content-type: text/plain; charset="US-ASCII"; x-default=true X-BeenThere: wireguard@lists.zx2c4.com X-Mailman-Version: 2.1.30rc1 Precedence: list List-Id: Development discussion of WireGuard List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: wireguard-bounces@lists.zx2c4.com Sender: "WireGuard" Let's reject unreasonable folio sizes early, where we can still fail. We'll add sanity checks to prepare_compound_head/prepare_compound_page next. Is there a way to configure a system such that unreasonable folio sizes would be possible? It would already be rather questionable. If so, we'd probably want to bail out earlier, where we can avoid a WARN and just report a proper error message that indicates where something went wrong such that we messed up. Signed-off-by: David Hildenbrand --- mm/memremap.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/mm/memremap.c b/mm/memremap.c index b0ce0d8254bd8..a2d4bb88f64b6 100644 --- a/mm/memremap.c +++ b/mm/memremap.c @@ -275,6 +275,9 @@ void *memremap_pages(struct dev_pagemap *pgmap, int nid) if (WARN_ONCE(!nr_range, "nr_range must be specified\n")) return ERR_PTR(-EINVAL); + if (WARN_ONCE(pgmap->vmemmap_shift > MAX_FOLIO_ORDER, + "requested folio size unsupported\n")) + return ERR_PTR(-EINVAL); switch (pgmap->type) { case MEMORY_DEVICE_PRIVATE: -- 2.50.1