From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 294C13655DB; Tue, 2 Jun 2026 17:25:58 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1780421160; cv=none; b=rYULutYjCex8bAvVoN1plSD/LMnSOAf+N9B+CKvnGdxjWTfcc7Pvt8U7X+SQbihauN98m3Ifi7nWH6saxQ96L6R9VEAM3IFst8TV09N9VltduirPiHQ/8WM+95c3L6GoIbbqCDP/UGmGAG8Ge9FVeMcqekXyrXaDTXYa3TM9GIo= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1780421160; c=relaxed/simple; bh=a5a5ljYBkMcosKeZd76EEJBkTbTnm9xS61a4Pk60/D8=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=d5ebyjK6vjZw8SJnchOOAV0UZuHfVHbqhzjzLPaLx9cEIQGx+It/VKfFxAS/qALvOtb128AxcyahaC0jELZH9FHq/ijmwYUPuskY1G/o77FnAuRmply2G1Fcf9T61tRxeYqCk0V+O+MLhmxNFDIUxdoP1O14Qisw/2+VYHIuQyM= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=FgU+bvAw; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="FgU+bvAw" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 4C1991F00893; Tue, 2 Jun 2026 17:25:57 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1780421158; bh=kfe19sVn9ZhdUldoutwKGgWSVE+tCqxFrQg7po2PBy0=; h=Date:Subject:To:Cc:References:From:In-Reply-To; b=FgU+bvAwoVjr76+Fer3oZ7cSF5VHreVThRx31VnTidu4O49pZYUriWac6WrwD/WK7 Cx4b8tM3Z+hEWG2MlX1YJR6E7yC+u6DBgjCO5DIqOIQs7d2Xci2/2f4bbMaVVWTyEw Kf/plgXN49UuYAkff0TxP3OVRQ+cwfRpW5yDehmNUKcsKx5H4xekCXm3bjP0C/F2r3 7Yog5Us50t7xcUs/0uGtGfW9UVJl6kYznUl6SAr+MsfHD4u4bKZFuBO9djJJbGAnZD GZ9BX6i3/+QfPEk8xe+VLT4Y2xI2OE4u4/MOCslNtrHOSpSXQRv/7nanSJ3DAnLLn3 gRna1C15fvU2Q== Message-ID: Date: Tue, 2 Jun 2026 19:25:56 +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] kernel/sys.c: fix prctl_set_auxv to use sizeof instead of user-supplied len To: Aiden Bowling , Lorenzo Stoakes Cc: Andrew Morton , Vlastimil Babka , linux-kernel@vger.kernel.org, stable@vger.kernel.org References: <20260602024001.14119-2-aidenlbowling56@gmail.com> From: "David Hildenbrand (Arm)" Content-Language: en-US Autocrypt: addr=david@kernel.org; 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charset=UTF-8 Content-Transfer-Encoding: 7bit On 6/2/26 16:14, Aiden Bowling wrote: > The issue is that using the user-supplied 'len' risks a partial write into mm- >>saved_auxv if they pass something smaller than the actual buffer size, even if > the buffer is validated. We should always copy the full buffer size after > validation to maintain consistency and prevent accidental partial data exposure/ > corruption. Which partial data exposure? -- Cheers, David