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[34.124.129.10]) by smtp.gmail.com with ESMTPSA id d9443c01a7336-2b242765b9fsm88519465ad.43.2026.03.30.02.38.53 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 30 Mar 2026 02:38:55 -0700 (PDT) Date: Mon, 30 Mar 2026 09:38:49 +0000 From: Pranjal Shrivastava To: Zhenzhong Duan Cc: iommu@lists.linux.dev, linux-kernel@vger.kernel.org, jgg@ziepe.ca, kevin.tian@intel.com, joro@8bytes.org, will@kernel.org, robin.murphy@arm.com, baolu.lu@linux.intel.com, stable@vger.kernel.org Subject: Re: [PATCH] iommufd: Fix return value of iommufd_fault_fops_write() Message-ID: References: <20260330030755.12856-1-zhenzhong.duan@intel.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: <20260330030755.12856-1-zhenzhong.duan@intel.com> On Sun, Mar 29, 2026 at 11:07:55PM -0400, Zhenzhong Duan wrote: > copy_from_user() may return number of bytes failed to copy, we should > not pass over this number to user space to cheat that write() succeed. > Instead, -EFAULT should be returned. > > Cc: stable@vger.kernel.org > Fixes: 07838f7fd529 ("iommufd: Add iommufd fault object") > Signed-off-by: Zhenzhong Duan > Reviewed-by: Lu Baolu Reviewed-by: Pranjal Shrivastava Thanks, Praan