From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-ej1-f54.google.com (mail-ej1-f54.google.com [209.85.218.54]) (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 F39F234AAE9 for ; Wed, 15 Jul 2026 14:23:51 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.218.54 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784125434; cv=none; b=kfIFz1ZwQx7YDpiAJKBHALRZg7VU8MB4505nlar5GVOMonEA3QWRrnA8TSwYG8iK8+NxHJVv8bYC71dwytKmJKSfrPgVUlmOb5VmfdnnBg56z/lKaUU1TwJWdPkDrbsVwLrh6CwpGIJ8ubpIiZ0ygcOL550uU3uIr3K31kxYEWs= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784125434; c=relaxed/simple; bh=p/A+hyd8Czmzv+d6bee7JEW5kyJdrX0FwFb3c+j1AQE=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=VqMFOFvLe1DAhNp9qnA11OwhNVVaZPVnw/fMSB+EQJKtJwXcsLIhy/xeSwJ8ieA4Ze6Ax+1xhtj2oLunbfoJ8hV9skicgYUyia97k7Ty+VOJMDFt+rHHeZeYimXmsPAI09HHbsDhFwNSH7z2rBN6ZCfSwLmCYKAp0Q3fnf7Ul7U= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com; spf=pass smtp.mailfrom=gmail.com; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b=qYr3sTAQ; arc=none smtp.client-ip=209.85.218.54 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=gmail.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="qYr3sTAQ" Received: by mail-ej1-f54.google.com with SMTP id a640c23a62f3a-c12614b81c9so1022576866b.3 for ; Wed, 15 Jul 2026 07:23:51 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20251104; t=1784125430; x=1784730230; darn=lists.linux.dev; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to:content-type; bh=b3M40eRQW8Z0pMjSw8FZJIlwcW2HMM9RvErrQLP04DY=; b=qYr3sTAQa+lHajUv5IGGnXonxQikbxQLrTdqrF2yMkBcz8Ux1hxmGNKXmX0bCpJTYG /eOxx/3FqPFpFOe3h6Z03V22izbqSVDlVSLIZiarBEaGw0yJ9/HlUE5e2r5/ufBiKuOI LrQUXl3k4AvPM8+BfXpCylrWoXuk/TL9bTjPvqn9ewa43II4GWhBD4kRfTkym1A+TvOM 8+HzDsXBXUa1ZMlB5C/zX0WHMEhn8ant/iH124aNFIblN+hN5pLlBQU0JW6GYZCHjAan yrz6+Yjo4awHrVwd96s52f3iiDfCatKPXsFHV1Uq5CIkMXcCrARgD3FBFhMc5H8Qqh4S BHMA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1784125430; x=1784730230; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-gg:x-gm-message-state:from :to:cc:subject:date:message-id:reply-to:content-type; bh=b3M40eRQW8Z0pMjSw8FZJIlwcW2HMM9RvErrQLP04DY=; b=gmZMsKzymRkmBBS6vXT5TJoYJEGkiHchkt+X53t7PkOrrFXTCMoACqD2TO3x8cZKPT V+LRE5EHH5crY7XQP7+sgaJLsBFp2nx/N5BwBVdLIvuUlOuVcicj7lyOmNMN/4zWlp3a yRy5pavOSuBQFURpDoJfWtweWN6GQQg5QMzOeWdrjl7Ao3Ha6yplY2MLDebT3O+aBEcV UYAPbyb8+QvNpDEflsDcYnDNFY6wuEmGWEVgz1m9Y2LFLxlFjiEqqfoneqGTLJY+lf5V wOoUIvlWgQ5gDBd9G5gElJMvvdTG12cucwTVoTugUaA1CeeaR/agi61Kf5BESagIDUYL ndwg== X-Forwarded-Encrypted: i=1; AHgh+RpUVDVK64p74dhjsNgMyWEdc+Iyn2g+p1aqxNe9Ej3aUHjWbbti8Ybyn+bWTakRG9DwXL+RdatvWddDG1zWvA==@lists.linux.dev X-Gm-Message-State: AOJu0YwOfUDwhZTUtCi7hgOBmi/WM0aeO6gxRxgwHIkwEShPgoWTi4YE Ho1mABW7AUXRgQFSAfVsVpXt/jp6Bz24ZsPGvLExWwptGNr0ac4x4O2F X-Gm-Gg: AfdE7cm4t7LXgFBgYUXEpwyhgpsYv4AvAxd0/+uuVs8XNbfBU6b1g+TUhI+JD3aag4i LO2ESp8wTdTDGOQo6JKYnGNtuE8pPXaSlPzwVM0/vcfqFrMe7ARg6F5lxh4jhUDb8jpdUcwlG1G 4T1/I37m6rVMhAqigTrqUMUiRBPOBvGswW5yP293o5J4Wq8pRWsdfiXfYAwi1sdACgDcYLEC/7h mit1lBUBNJlELYHJ5khVqyAskn7p6fwiRb1AvfqPPE/O3TH7m5IcRwB7bUifbN2fNm5vTXkdk4Z hz4rvdPQcmEyGFmEQhxUiTy82Be9qwBK74t+WlEq8QfJa9/ZgRA8m4TLGMPFfKwOjIoUDXboxJ8 IYmOqMnhGgn+8jPFkCFuumJ93D2DgGnpPNW0/9esddaDAvFffk+o+vWZbPdWqteYujcbAISwM34 hvzxh38g0vNRajqMV8u4Mk2pHrC9bgM53E+Rl7bj/79m5Lo44vuSJh7bUpchP09ZXlVO6bk8oUZ bTe X-Received: by 2002:a17:907:d16:b0:c15:bc2d:e938 with SMTP id a640c23a62f3a-c16792a5887mr227159666b.32.1784125429946; Wed, 15 Jul 2026 07:23:49 -0700 (PDT) Received: from misharu.home (2a02-a463-a071-0-8f3f-3afb-28f6-19c0.fixed6.kpn.net. [2a02:a463:a071:0:8f3f:3afb:28f6:19c0]) by smtp.gmail.com with ESMTPSA id a640c23a62f3a-c168744bd40sm38743766b.43.2026.07.15.07.23.49 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 15 Jul 2026 07:23:49 -0700 (PDT) From: Hari Mishal To: Amit Shah , Arnd Bergmann , Greg Kroah-Hartman , Gerd Hoffmann , "Michael S . Tsirkin" , Jason Wang , David Hildenbrand , Henrik Rydberg Cc: Xuan Zhuo , =?UTF-8?q?Eugenio=20P=C3=A9rez?= , virtualization@lists.linux.dev, linux-kernel@vger.kernel.org, linux-input@vger.kernel.org, Hari Mishal Subject: [PATCH 2/4] virtio_input: validate device-reported multitouch slot count Date: Wed, 15 Jul 2026 16:22:41 +0200 Message-ID: <20260715142337.22811-3-harimishal1@gmail.com> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20260715142337.22811-1-harimishal1@gmail.com> References: <20260715142337.22811-1-harimishal1@gmail.com> Precedence: bulk X-Mailing-List: virtualization@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit nslots is derived from the ABS_MT_SLOT maximum reported by the virtio device. A device could report a bogus maximum (e.g. -1) making nslots = 0, which input_mt_init_slots() does not reject; it returns success without allocating any slot storage, silently leaving the device registered as multitouch capable with no backing state. Reject non-positive slot counts before calling input_mt_init_slots(). Assisted-by: gkh_clanker:t1000 Signed-off-by: Hari Mishal --- drivers/virtio/virtio_input.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/drivers/virtio/virtio_input.c b/drivers/virtio/virtio_input.c index deec24e8e682..2cc19782cdd3 100644 --- a/drivers/virtio/virtio_input.c +++ b/drivers/virtio/virtio_input.c @@ -312,6 +312,10 @@ static int virtinput_probe(struct virtio_device *vdev) if (test_bit(ABS_MT_SLOT, vi->idev->absbit)) { nslots = input_abs_get_max(vi->idev, ABS_MT_SLOT) + 1; + if (nslots <= 0) { + err = -EINVAL; + goto err_mt_init_slots; + } err = input_mt_init_slots(vi->idev, nslots, 0); if (err) goto err_mt_init_slots; -- 2.43.0