From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id E947E18453B; Mon, 5 Aug 2024 17:59:36 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1722880777; cv=none; b=CFOw1QJnYS430U5Yow4NbY3/2yLpqZptLpjPrs9rye9D1ycTR0U22A2ZCI9tyaTOKDEtL9IRtIJ1wSsc59x94yi9chI86+0OvReQgDM1sHqdliCWQuPlKkTgCqSAABUYv28v2EKswdz160OCaQzFq8dFM36C37e8z9mKPUfjW20= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1722880777; c=relaxed/simple; bh=O9Iyc49rPuU+RjCe9qJiRt4yfIA/RXxWPaivUdrXFHM=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=MSd9FeKufbs30XlX6Xzt+gbkQ/pRbolPMNbTOtBykPRo5Tc1V8sqWG91eL9NNU1gNgbd4bSvDsJpnu48qnFUU0kvXMf9uUvOQYsjYHd7dbw+tmd7jhtnuKsIRLwOD96NN+fSuNqwjF9GcKfMwPVPBhcSBHFe2xOPlYGm1igNh5A= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=VAynaGJP; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="VAynaGJP" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 77E38C32782; Mon, 5 Aug 2024 17:59:35 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1722880776; bh=O9Iyc49rPuU+RjCe9qJiRt4yfIA/RXxWPaivUdrXFHM=; h=From:To:Cc:Subject:Date:From; b=VAynaGJPHW6NR/xJWaFqqnNwulTBJOW8bkGUZx2usXR5CE8CmNiztPbnM9VsEriBJ cnrBebtZF3swgtA8EyqRg7yckIWViepFO1D/YbQ7J7oLaQ+n3MjtjRm49uFIvx04hC M+LoUtv7zj5Xi9xu3JKwiJ4fELkEgM3kHtxziwnRWdprc//z2u0LEqV62v2W3xm9wD Cef3QFVVSkAlc7V4PMepJhbqHSXfqXSO8HLdEZWiZzZBZaJwU7Omd3OY/IUbUwMSsz XoZJtEjS+GwqwTLu9qjmkDd55ej+nUYv9h6RBgqeB1ejNj/V/fnTFAVSLohArWJ4GP BDFjkuig9Bu5g== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Tetsuo Handa , syzbot , Dmitry Torokhov , Linus Torvalds , Sasha Levin , linux-input@vger.kernel.org Subject: [PATCH AUTOSEL 4.19] Input: MT - limit max slots Date: Mon, 5 Aug 2024 13:59:33 -0400 Message-ID: <20240805175934.3257938-1-sashal@kernel.org> X-Mailer: git-send-email 2.43.0 Precedence: bulk X-Mailing-List: linux-input@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore X-stable-base: Linux 4.19.319 Content-Transfer-Encoding: 8bit From: Tetsuo Handa [ Upstream commit 99d3bf5f7377d42f8be60a6b9cb60fb0be34dceb ] syzbot is reporting too large allocation at input_mt_init_slots(), for num_slots is supplied from userspace using ioctl(UI_DEV_CREATE). Since nobody knows possible max slots, this patch chose 1024. Reported-by: syzbot Closes: https://syzkaller.appspot.com/bug?extid=0122fa359a69694395d5 Suggested-by: Dmitry Torokhov Signed-off-by: Tetsuo Handa Signed-off-by: Linus Torvalds Signed-off-by: Sasha Levin --- drivers/input/input-mt.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/input/input-mt.c b/drivers/input/input-mt.c index 6c7326c93721c..fd01c9306e66c 100644 --- a/drivers/input/input-mt.c +++ b/drivers/input/input-mt.c @@ -48,6 +48,9 @@ int input_mt_init_slots(struct input_dev *dev, unsigned int num_slots, return 0; if (mt) return mt->num_slots != num_slots ? -EINVAL : 0; + /* Arbitrary limit for avoiding too large memory allocation. */ + if (num_slots > 1024) + return -EINVAL; mt = kzalloc(struct_size(mt, slots, num_slots), GFP_KERNEL); if (!mt) -- 2.43.0