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 D9DE91DA317; Wed, 3 Jul 2024 05:02:44 +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=1719982965; cv=none; b=dFs3jkKLvy7wXUqwtMR4RgWAhK3GkWkCFH4/TLFCAandkQ9A8EGcuB1YYuIQZUAZgeeCJci9JMtC1kjbbqYaNmnQJKcCcQRzCGiYmRT00JnILRBSWuP431o8gSwi6otnvo4YSd9PQ+cOyuIMMhtey8AMRvgaK2Cdm85e7aLN6S4= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1719982965; c=relaxed/simple; bh=tqodm5LXmDW7fB6efoOZfjUgq6nKZ30g0K3nhfm75yM=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=a/VTEydzDGAhkOucua30EDlgCjw0nqmBhfRqH6PkcQex0wfVg4jmj9mw+L6v+F3TskDLSN6FLK3e9q6EgxHh7CUZgPTT8STtHE5t4IBF37i1cuqW4z6MsgYvx5pDryz70zA9FYD06Gkr+popyw/+YWBd7sBU7HytvO6dLBaxAYE= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=X7kBDFBP; 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="X7kBDFBP" Received: by smtp.kernel.org (Postfix) with ESMTPSA id C9218C32781; Wed, 3 Jul 2024 05:02:42 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1719982964; bh=tqodm5LXmDW7fB6efoOZfjUgq6nKZ30g0K3nhfm75yM=; h=Date:Subject:To:Cc:References:From:In-Reply-To:From; b=X7kBDFBP0YomTwTukk3LQeIHq6XxIe2ZETRVYi0TTM6tEkT2DNHKvczpYdODOFgfI DDo0dxz65qyzTT2NdTS68a2NSomJB3gcfx2qUFXFRTkeziW3RC9VUIYcFmt3jIkVxO LbYMWT4o1IPOpAFtaQj0g0jD+JM0k9Ocu5evoGxkH9msY7lFHLjvztPQ7fp3iK18ec fs0xhxsCO6sijUtsJOVjQ+dl/u4S3+y7xl3OkpD301xnyjw986Uc0ydwW5WidhUZdg WDmOs52iflfu1dwqEyQHBgDEtSz5O7kidrvKfYlzNBV9qa7GxMK6BSLgBTVI6jW88r naqC1acD4t9Eg== Message-ID: Date: Wed, 3 Jul 2024 07:02:40 +0200 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] nfc: pn533: Add poll mod list filling check To: Aleksandr Mishin , Samuel Ortiz Cc: netdev@vger.kernel.org, linux-kernel@vger.kernel.org, lvc-project@linuxtesting.org References: <20240702093924.12092-1-amishin@t-argos.ru> Content-Language: en-US From: Krzysztof Kozlowski Autocrypt: addr=krzk@kernel.org; keydata= xsFNBFVDQq4BEAC6KeLOfFsAvFMBsrCrJ2bCalhPv5+KQF2PS2+iwZI8BpRZoV+Bd5kWvN79 cFgcqTTuNHjAvxtUG8pQgGTHAObYs6xeYJtjUH0ZX6ndJ33FJYf5V3yXqqjcZ30FgHzJCFUu JMp7PSyMPzpUXfU12yfcRYVEMQrmplNZssmYhiTeVicuOOypWugZKVLGNm0IweVCaZ/DJDIH gNbpvVwjcKYrx85m9cBVEBUGaQP6AT7qlVCkrf50v8bofSIyVa2xmubbAwwFA1oxoOusjPIE J3iadrwpFvsZjF5uHAKS+7wHLoW9hVzOnLbX6ajk5Hf8Pb1m+VH/E8bPBNNYKkfTtypTDUCj NYcd27tjnXfG+SDs/EXNUAIRefCyvaRG7oRYF3Ec+2RgQDRnmmjCjoQNbFrJvJkFHlPeHaeS BosGY+XWKydnmsfY7SSnjAzLUGAFhLd/XDVpb1Een2XucPpKvt9ORF+48gy12FA5GduRLhQU vK4tU7ojoem/G23PcowM1CwPurC8sAVsQb9KmwTGh7rVz3ks3w/zfGBy3+WmLg++C2Wct6nM Pd8/6CBVjEWqD06/RjI2AnjIq5fSEH/BIfXXfC68nMp9BZoy3So4ZsbOlBmtAPvMYX6U8VwD TNeBxJu5Ex0Izf1NV9CzC3nNaFUYOY8KfN01X5SExAoVTr09ewARAQABzSVLcnp5c3p0b2Yg S296bG93c2tpIDxrcnprQGtlcm5lbC5vcmc+wsGVBBMBCgA/AhsDBgsJCAcDAgYVCAIJCgsE FgIDAQIeAQIXgBYhBJvQfg4MUfjVlne3VBuTQ307QWKbBQJgPO8PBQkUX63hAAoJEBuTQ307 QWKbBn8P+QFxwl7pDsAKR1InemMAmuykCHl+XgC0LDqrsWhAH5TYeTVXGSyDsuZjHvj+FRP+ gZaEIYSw2Yf0e91U9HXo3RYhEwSmxUQ4Fjhc9qAwGKVPQf6YuQ5yy6pzI8brcKmHHOGrB3tP /MODPt81M1zpograAC2WTDzkICfHKj8LpXp45PylD99J9q0Y+gb04CG5/wXs+1hJy/dz0tYy iua4nCuSRbxnSHKBS5vvjosWWjWQXsRKd+zzXp6kfRHHpzJkhRwF6ArXi4XnQ+REnoTfM5Fk VmVmSQ3yFKKePEzoIriT1b2sXO0g5QXOAvFqB65LZjXG9jGJoVG6ZJrUV1MVK8vamKoVbUEe 0NlLl/tX96HLowHHoKhxEsbFzGzKiFLh7hyboTpy2whdonkDxpnv/H8wE9M3VW/fPgnL2nPe xaBLqyHxy9hA9JrZvxg3IQ61x7rtBWBUQPmEaK0azW+l3ysiNpBhISkZrsW3ZUdknWu87nh6 eTB7mR7xBcVxnomxWwJI4B0wuMwCPdgbV6YDUKCuSgRMUEiVry10xd9KLypR9Vfyn1AhROrq AubRPVeJBf9zR5UW1trJNfwVt3XmbHX50HCcHdEdCKiT9O+FiEcahIaWh9lihvO0ci0TtVGZ MCEtaCE80Q3Ma9RdHYB3uVF930jwquplFLNF+IBCn5JRzsFNBFVDXDQBEADNkrQYSREUL4D3 Gws46JEoZ9HEQOKtkrwjrzlw/tCmqVzERRPvz2Xg8n7+HRCrgqnodIYoUh5WsU84N03KlLue MNsWLJBvBaubYN4JuJIdRr4dS4oyF1/fQAQPHh8Thpiz0SAZFx6iWKB7Qrz3OrGCjTPcW6ei OMheesVS5hxietSmlin+SilmIAPZHx7n242u6kdHOh+/SyLImKn/dh9RzatVpUKbv34eP1wA GldWsRxbf3WP9pFNObSzI/Bo3kA89Xx2rO2roC+Gq4LeHvo7ptzcLcrqaHUAcZ3CgFG88CnA 6z6lBZn0WyewEcPOPdcUB2Q7D/NiUY+HDiV99rAYPJztjeTrBSTnHeSBPb+qn5ZZGQwIdUW9 YegxWKvXXHTwB5eMzo/RB6vffwqcnHDoe0q7VgzRRZJwpi6aMIXLfeWZ5Wrwaw2zldFuO4Dt 91pFzBSOIpeMtfgb/Pfe/a1WJ/GgaIRIBE+NUqckM+3zJHGmVPqJP/h2Iwv6nw8U+7Yyl6gU BLHFTg2hYnLFJI4Xjg+AX1hHFVKmvl3VBHIsBv0oDcsQWXqY+NaFahT0lRPjYtrTa1v3tem/ JoFzZ4B0p27K+qQCF2R96hVvuEyjzBmdq2esyE6zIqftdo4MOJho8uctOiWbwNNq2U9pPWmu 4vXVFBYIGmpyNPYzRm0QPwARAQABwsF8BBgBCgAmAhsMFiEEm9B+DgxR+NWWd7dUG5NDfTtB YpsFAmA872oFCRRflLYACgkQG5NDfTtBYpvScw/9GrqBrVLuJoJ52qBBKUBDo4E+5fU1bjt0 Gv0nh/hNJuecuRY6aemU6HOPNc2t8QHMSvwbSF+Vp9ZkOvrM36yUOufctoqON+wXrliEY0J4 ksR89ZILRRAold9Mh0YDqEJc1HmuxYLJ7lnbLYH1oui8bLbMBM8S2Uo9RKqV2GROLi44enVt vdrDvo+CxKj2K+d4cleCNiz5qbTxPUW/cgkwG0lJc4I4sso7l4XMDKn95c7JtNsuzqKvhEVS oic5by3fbUnuI0cemeizF4QdtX2uQxrP7RwHFBd+YUia7zCcz0//rv6FZmAxWZGy5arNl6Vm lQqNo7/Poh8WWfRS+xegBxc6hBXahpyUKphAKYkah+m+I0QToCfnGKnPqyYIMDEHCS/RfqA5 t8F+O56+oyLBAeWX7XcmyM6TGeVfb+OZVMJnZzK0s2VYAuI0Rl87FBFYgULdgqKV7R7WHzwD uZwJCLykjad45hsWcOGk3OcaAGQS6NDlfhM6O9aYNwGL6tGt/6BkRikNOs7VDEa4/HlbaSJo 7FgndGw1kWmkeL6oQh7wBvYll2buKod4qYntmNKEicoHGU+x91Gcan8mCoqhJkbqrL7+nXG2 5Q/GS5M9RFWS+nYyJh+c3OcfKqVcZQNANItt7+ULzdNJuhvTRRdC3g9hmCEuNSr+CLMdnRBY fv0= In-Reply-To: <20240702093924.12092-1-amishin@t-argos.ru> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit On 02/07/2024 11:39, Aleksandr Mishin wrote: > In case of im_protocols value is 1 and tm_protocols value is 0 this Which im protocol has value 1 in the mask? The pn533_poll_create_mod_list() handles all possible masks, so your case is just not possible to happen. This patch is purely to satisfy (your) static analyzers, so this should be clear in commit msg. You are not fixing any bug but adding sort of defensive code and suppresion of false-positive warning... > combination successfully passes the check > 'if (!im_protocols && !tm_protocols)' in the nfc_start_poll(). > But then after pn533_poll_create_mod_list() call in pn533_start_poll() > poll mod list will remain empty and dev->poll_mod_count will remain 0 > which lead to division by zero. > > Add poll mod list filling check. > > Found by Linux Verification Center (linuxtesting.org) with SVACE. > > Fixes: dfccd0f58044 ("NFC: pn533: Add some polling entropy") > Signed-off-by: Aleksandr Mishin > --- > drivers/nfc/pn533/pn533.c | 5 +++++ > 1 file changed, 5 insertions(+) > > diff --git a/drivers/nfc/pn533/pn533.c b/drivers/nfc/pn533/pn533.c > index b19c39dcfbd9..e2bc67300a91 100644 > --- a/drivers/nfc/pn533/pn533.c > +++ b/drivers/nfc/pn533/pn533.c > @@ -1723,6 +1723,11 @@ static int pn533_start_poll(struct nfc_dev *nfc_dev, > } > > pn533_poll_create_mod_list(dev, im_protocols, tm_protocols); > + if (!dev->poll_mod_count) { > + nfc_err(dev->dev, > + "Poll mod list is empty\n"); Odd wrapping. > + return -EINVAL; > + } > > /* Do not always start polling from the same modulation */ > get_random_bytes(&rand_mod, sizeof(rand_mod)); Best regards, Krzysztof