From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-ot1-f47.google.com (mail-ot1-f47.google.com [209.85.210.47]) (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 D3D0E2EACEF for ; Sat, 30 May 2026 01:44:09 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.210.47 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1780105451; cv=none; b=KvURrzqZ5koz1pzAWFP+ZC9tMLZMiY7uJOHZyQSG6KOs5F5HwRDPte8AZ5YebuEyekJB5aZ6x1zIFDFXEHQszpQGzK5ErLmYQ8VXoLFGItcJSbKHQOrQDnSlQJAiLXH9cr/6nv2aprxbyrortZGnjHslYun29soJ3N8ECGSIg3k= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1780105451; c=relaxed/simple; bh=RoQnkjSAGQlltUOHi6qTBWzLW/MPRpTjVtIir1Bku8o=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=IhzwobvNmar14FXrFiLxNFT4iI0x/9FVwNdRZyKT2n4DF/NLfjL9S0Sqod2iZXaL0bYCLR9+ZsbDmy6XYK0r4XauYsNEIKyzPPEg1eqRVfWoZHYIAo9LA3XZ4vZvR0pIbQHf5ZLapQCukxbEJlqpR6jbEn3rCEChcam66PBuAk4= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=ieee.org; spf=pass smtp.mailfrom=ieee.org; dkim=pass (1024-bit key) header.d=ieee.org header.i=@ieee.org header.b=DxvId/bX; arc=none smtp.client-ip=209.85.210.47 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=ieee.org Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=ieee.org Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=ieee.org header.i=@ieee.org header.b="DxvId/bX" Received: by mail-ot1-f47.google.com with SMTP id 46e09a7af769-7e5fd39cf11so7171210a34.0 for ; Fri, 29 May 2026 18:44:09 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ieee.org; s=google; t=1780105449; x=1780710249; darn=vger.kernel.org; h=content-transfer-encoding:in-reply-to:from:content-language :references:cc:to:subject:user-agent:mime-version:date:message-id :from:to:cc:subject:date:message-id:reply-to; bh=X+zTIztgsGKEhgjsVhvr5Rv5TrBYFcWsdOmt+WZ+x9w=; b=DxvId/bX6y9ovt3FpOHoF/jE8a+2ZK+wO1h+JJstdq1pihW80TGRlPSKVszpS7/Efj YeVhEK5WftrE6UJNCse0z0hN9zhj2hOcNgzoo94sO2+Ifq5Yd1XkVNUYxyfEpqbe2JtU BICSZC2kiX0GAWnMOs7u+/dJk0Gkpgz79rHqg= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1780105449; x=1780710249; h=content-transfer-encoding:in-reply-to:from:content-language :references:cc:to:subject:user-agent:mime-version:date:message-id :x-gm-gg:x-gm-message-state:from:to:cc:subject:date:message-id :reply-to; bh=X+zTIztgsGKEhgjsVhvr5Rv5TrBYFcWsdOmt+WZ+x9w=; b=cIv/8d0M3nxiaGaKaJNup0OxR/rBxxIzqL79hUowsLQQjDA8ciNSN3ZqqJB9HCksN0 dHJcZJdesGYUcl276Kq2RnlFLvjJg2nhvnKg8p1N3NhMpAk9U0rhxhn3jKXBrgKh+hD6 oEhUtB3iJugpkvFbN9Z70stw15f9bxSpkPnWjyJCJ9Dvt0sLHVsZ97W8rca6y1YgyUlc GHi+DdjW54QqRphWtBj+Xy/AvIVPxgyJNnKkTBvWeBuF5Oy1Kg3jnZX80nghUE1/c2mL UQEtCPd3u8Ss6BnusMtKcp4TDNUAP9Xc6g7qvJH1PJ1gX9S/APc0+u0/Y+57G24BGBsh odOA== X-Forwarded-Encrypted: i=1; AFNElJ+SXvMJPwttVTYEuToHOVKf4yIb8APXk4GTp1jUpHX+35YMtvoO6sgDSSjIOrjYYJF2yKNfEPgN39Zz0qo=@vger.kernel.org X-Gm-Message-State: AOJu0YyOwPNF6Ovk1psn4agIdyKQ+UBTRsJStzKNTlSWA0D96SEVokAu NzXnm7WE7PdMW3AysqIZXN4E/b5TW34pDoU4Jq6o9v/uLDmS3xU8mhuKCzB04tbWHA== X-Gm-Gg: Acq92OG9fL8P6dtCpQXVgSKXUJ2pI+EUP+zsaw57uwrXLoMqoAKkaUHrClcG2Lte5iR PX3NSjzT1iQZj9WwyltfBoQ06Smv32FMu0bEbrkgoqhYU5SNuuCRpyodQ978j2jWrikDpPSp4N6 wmE4rMHJLVz5PZllJHzbSnCwthxEQGmdcN3NhbIZYsmF/67u4REhpSE1A3BsF6rXXFx03jgZdsI 9+32h0jVBYEig8xW/UmjWDLNxnz2ORcsZZZSae2ktiwryXublmnF0VHHP40MREZdtrno980W+jr lhz+QAduLykkPbXHxywhGfzeoeOc95DtPuNVPfw4S4OYYycnAgG/43B8MmzLWte+rxr+5XNUJ64 xCkj6IxnEUs9ZAq5bxXLf22HouBwvPO7DQwQDidD03fduGoc0Y5dVuoowvLoPO/9NQau/zPUZMV /TeIdcyrAEmIidruPc3yQT1Fsnd1WZ X-Received: by 2002:a05:6820:1996:b0:69d:795a:5e8b with SMTP id 006d021491bc7-69e105d4115mr948538eaf.60.1780105448859; Fri, 29 May 2026 18:44:08 -0700 (PDT) Received: from [172.22.22.28] ([73.62.185.64]) by smtp.googlemail.com with ESMTPSA id 586e51a60fabf-43c94078170sm2262599fac.14.2026.05.29.18.44.07 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Fri, 29 May 2026 18:44:08 -0700 (PDT) Message-ID: <284d5062-460e-496c-b700-2275deb7f8bb@ieee.org> Date: Fri, 29 May 2026 20:44:06 -0500 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] rbd: check snap_count against RBD_MAX_SNAP_COUNT To: Rosen Penev , linux-block@vger.kernel.org Cc: Ilya Dryomov , Dongsheng Yang , Jens Axboe , Nathan Chancellor , Nick Desaulniers , Bill Wendling , Justin Stitt , "open list:RADOS BLOCK DEVICE (RBD)" , open list , "open list:CLANG/LLVM BUILD SUPPORT:Keyword:b(?i:clang|llvm)b" References: <20260530011255.52916-1-rosenp@gmail.com> Content-Language: en-US From: Alex Elder In-Reply-To: <20260530011255.52916-1-rosenp@gmail.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit On 5/29/26 8:12 PM, Rosen Penev wrote: > snap_count is u32 but the comparison is against a SIZE_MAX-derived value > (~2^61 on 64-bit), which clang flags as always false with > -Wtautological-constant-out-of-range-compare. > > The proper check here should be that snap_count does not go over > RBD_MAX_SNAP_COUNT. > > Assisted-by: Opencode:Big-pickle > Signed-off-by: Rosen Penev Looks good to me. Reviewed-by: Alex Elder > --- > drivers/block/rbd.c | 7 ++----- > 1 file changed, 2 insertions(+), 5 deletions(-) > > diff --git a/drivers/block/rbd.c b/drivers/block/rbd.c > index 94709466ad19..25215c209484 100644 > --- a/drivers/block/rbd.c > +++ b/drivers/block/rbd.c > @@ -6075,12 +6075,9 @@ static int rbd_dev_v2_snap_context(struct rbd_device *rbd_dev, > > /* > * Make sure the reported number of snapshot ids wouldn't go > - * beyond the end of our buffer. But before checking that, > - * make sure the computed size of the snapshot context we > - * allocate is representable in a size_t. > + * beyond the end of our buffer. > */ > - if (snap_count > (SIZE_MAX - sizeof (struct ceph_snap_context)) > - / sizeof (u64)) { > + if (snap_count > RBD_MAX_SNAP_COUNT) { > ret = -EINVAL; > goto out; > }