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 154AE17C230; Mon, 5 Aug 2024 17:59:10 +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=1722880751; cv=none; b=AUGH2ULKvulBOs3+IYWytjOiUyCXbjv8kAM8d406ZvyDNzVJ9VsZ7K9HfegTAWjuMAlZm/t17ZOKCSS8oMFwL+ZBUHnPzR6Fk+m82UnxOcv8YqolDniFbcPRUtZUSmm6GRNH3f0rLMvAzOrX9pkwilDxgFy237cWClyOXTy+3PQ= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1722880751; c=relaxed/simple; bh=xlrR3WwL+cXJc1lqxFYvNtOrzzq8EIlyhO6U+rAUZkc=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=AlRUASLGUoPSBf3fVTGWoFmi6U/zFF+gy2jyj7JOM7phR3mrwNX74FTYnNIkC0Lpjb5YCrUNNYIQg364OMJlGbTtbYbTMAW/LEQpwsaPohjEe+uedj2+bYbW4ciT8ikyQ4bYLCEkHP51oqPK5Dkujqj21jnC5CtV6vA2axoyj3Q= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=HZdf67Wo; 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="HZdf67Wo" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 95CF3C4AF0B; Mon, 5 Aug 2024 17:59:09 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1722880750; bh=xlrR3WwL+cXJc1lqxFYvNtOrzzq8EIlyhO6U+rAUZkc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=HZdf67WolOzIGqpfbckZs+dBHZPEzaxFO8IqJB3zs3CZCqVWRP0tSWzObzwHSIYP+ qglFo7cWjkOxhmZqMc9dOKBCTWeLFXDqlXG8+QfJsq7RMHMvweJmRlFj9zUkQx2REm 6+C0cgwn+yfpmBr/GjOfre7hlH1njWMTz9ZoxLx5l+2D/lZUpbTx2M1yyIG8gzMiGR cRAYAmlyGAVYbyDvd8IsU37iTrq/rLr1l/9NBmNnYMpoKnGYJ/l3x4so6gH6sIGUI/ P+8cli1kgLxVg0EkepnVGG5j4uSWYlag7BBvZ7ftXArN+Iuus2ghpFM9tV8jSq5PCA hgZPoggj10CXA== 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 5.15 4/4] Input: MT - limit max slots Date: Mon, 5 Aug 2024 13:58:52 -0400 Message-ID: <20240805175857.3256338-4-sashal@kernel.org> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20240805175857.3256338-1-sashal@kernel.org> References: <20240805175857.3256338-1-sashal@kernel.org> 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 5.15.164 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 44fe6f2f063ce..d0f8c31d7cc04 100644 --- a/drivers/input/input-mt.c +++ b/drivers/input/input-mt.c @@ -45,6 +45,9 @@ 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