From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-pl1-f172.google.com (mail-pl1-f172.google.com [209.85.214.172]) (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 266CA384CEB for ; Wed, 3 Jun 2026 14:15:11 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.214.172 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1780496113; cv=none; b=tfwYTP4+PRXoEX6DvSO/LNTHzIcfC1gtUkgqjVdQRckBDgWPEg2M0Ue2cY3N0Gs2Dyz6N0qWp2Fqa5gnFk6xJwO4q4ENCPLtPVvdUl/XaQSaBps122e+OBa3lzAVwAubQd7BP76PjTmCXnp29wTFEujVLtpFiCGyq3oAK9s9BV0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1780496113; c=relaxed/simple; bh=np8yTAGyoHyKjiswZIV0dx/wnbvVdMEDawhwZGw0qTY=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=l/JA45tCi2LriBcHOpUhO+eNTG2AVTwSs6z3qHveR1s2bkJa8oROtoCZxPcbg8hPVadhovtCBmWZLlibY/md3eyaYFb7IJGJLQCb2LztSPMEQ2s3THgoDFUhflhUdtL2NOYaS+ZC0VS/7Q5HqBqrPNSNLuVm/fFFkEyr3vLeXyU= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com; spf=pass smtp.mailfrom=google.com; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b=hmjGPsCg; arc=none smtp.client-ip=209.85.214.172 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=google.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="hmjGPsCg" Received: by mail-pl1-f172.google.com with SMTP id d9443c01a7336-2c0b1a48855so89685ad.0 for ; Wed, 03 Jun 2026 07:15:11 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20251104; t=1780496111; x=1781100911; darn=vger.kernel.org; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:from:to:cc:subject:date:message-id:reply-to; bh=6eaHVbDYv4hX/p3BkMc9yoT5MuLzy6Lq3RWtBuTNxcE=; b=hmjGPsCg1liRDzIKs2eWjset5lC/gH1E8c05Fj0ZygZiJr+e9nOXECrN6+9/abOGLF 78wasu2LaQibM3erTF1FrKXO043gfSWJlX527gROJhD5J7/x43wm78ybWKuWci/THnHS rWWZq3B9oRaW9L3u3oz6m9HBPbf0gM6F5Cg7sWsrxOfuhVfVjRxkbfoUNiZAPCU4A6kP aYoK2pMRz0xpNy8767THIoW6eGRJThMfOnyDcwSXjXKmjVDPF3Eds3KC9UnBsJjuO6Jd CUHDubEik6FwS45omUJPEbxlC2Zqs8vjSLjAuliA86hpE3c3txYXJoT9oa2RH917COoj aNuA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1780496111; x=1781100911; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:x-gm-gg:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=6eaHVbDYv4hX/p3BkMc9yoT5MuLzy6Lq3RWtBuTNxcE=; b=OJ/SkWv5ShFmFMtD+NFvTzGACApkc4n7L8gHq40EGoU3QT0keSxiRGauPGFhvt73V+ BEMtIC01ridztql7PM2TmYf66JLfXCjbKudTmWhGuW+o5wPlq2gwrJnxLLrF1mlzQQzO uXE02PS5bny3FRaIJQWPcSJC7ubQ735aPcNdDRl3WBQ4M7Vb8gekyWDiWBVwA9GWOrd2 ANQpd/ILticgTiHy1OZpuV0HL/jMtW05E7+m2NdnJ7oC8cZjrCoAjvM2G1CNfGuR2Mb7 YDI8Iis70WDRyqGeZYLZ+7U0vdxiuvQmnCCqKaXAha+sos3ceGTmLskYDavOCvTdQN2s Yk6g== X-Forwarded-Encrypted: i=1; AFNElJ/BeN3p/6S04RynBroSBax88LVcF/oW9E5bYAAPS9UjLAQQhJjV2IlEWLeasf27O7Lmci40ajaRxW/ntRI=@vger.kernel.org X-Gm-Message-State: AOJu0YzzUfJuqeXU0AoBMlHayNuKFOKFAEOxFRKuSMpEr5UDt1bfCx/n qluBbSFM21+UOi2zUvVv43C8PT68x+Afqe+x/JlbKVqNTzhFxIFLXs67WWXd4z0F/A== X-Gm-Gg: Acq92OHjaQB5RR2tHQSpmXjoSXvHLeS2vfG4ndiVE+I4/G9F6eF+ljqjNnVcFSoCIn0 GP6fr2r8RbD1ckAI/yzvrKPQn0ONlUQLGvMmn3yMlSUN2Itg5u6YzmzXH4bhdkR6lziXDEEQeI8 KPGyXQePJBkstOsyw10D28/GkOhMpyjFbqrnGkBtRLjuZ1jhG+e+Bk5SvYVsbUtSjlvHArVKvJX 8L1+dxDBBDU/yNrD3wS+96EwktDXwlZQPgZA4hAue5OJ0QIXRdpp8XhaQtZiecBxB3e58cD+OWR ZwcThlk9QpQEIhlkgq3SeZjYkVytdNmW3avt21hAtJtTbOwAZUFvItqqpsz/qgRlbHZBrUl8LMV ZVIWhv7dETtXqJfSdRAWeqblcC1tZgIYQDDK6TLG2i6mvIjjVy9zeXsTsvpQ/HjH5e0FuAeocPw e3m1XpNcNbVPdKdZRf8LWugHnhJAo6yOUpnpkFO2MeQbRKvGgPWhfxBq2jm+SNA+zIRUSEmU5Xc GNAiCavpA== X-Received: by 2002:a17:902:c405:b0:2bd:5fc9:27b9 with SMTP id d9443c01a7336-2c16fa720bamr1530475ad.3.1780496110631; Wed, 03 Jun 2026 07:15:10 -0700 (PDT) Received: from google.com (199.255.142.34.bc.googleusercontent.com. [34.142.255.199]) by smtp.gmail.com with ESMTPSA id d9443c01a7336-2c16629d40asm25583475ad.64.2026.06.03.07.15.08 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 03 Jun 2026 07:15:10 -0700 (PDT) Date: Wed, 3 Jun 2026 14:15:04 +0000 From: Pranjal Shrivastava To: Nicolin Chen Cc: jgg@nvidia.com, kevin.tian@intel.com, joro@8bytes.org, baolu.lu@linux.intel.com, iommu@lists.linux.dev, linux-kernel@vger.kernel.org, linux-kselftest@vger.kernel.org Subject: Re: [PATCH v1 4/7] iommufd: Reject invalid read count in iommufd_fault_fops_read() Message-ID: References: <85c118a606fbedc5c132a1f5ec223a5ba23b92d2.1780343944.git.nicolinc@nvidia.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <85c118a606fbedc5c132a1f5ec223a5ba23b92d2.1780343944.git.nicolinc@nvidia.com> On Mon, Jun 01, 2026 at 01:42:35PM -0700, Nicolin Chen wrote: > The read count must be large enough to hold one fault or a group's faults. > > iommufd_fault_fops_read() does not validate the count, but returns 0 as if > the read had succeeded while leaving the pending fault in the queue. > > Return -EINVAL in the undersize cases. > > Fixes: 07838f7fd529 ("iommufd: Add iommufd fault object") > Cc: stable@vger.kernel.org > Signed-off-by: Nicolin Chen Reviewed-by: Pranjal Shrivastava Thanks, Praan