From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Miller Subject: Re: [PATCH] net: socket: fix recvmmsg not returning error from sock_error Date: Tue, 21 Feb 2017 13:35:58 -0500 (EST) Message-ID: <20170221.133558.1628815110115665532.davem@davemloft.net> References: <20170221173551.3471-1-maxime.jayat@mobile-devices.fr> Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit Cc: acme@redhat.com, netdev@vger.kernel.org, linux-kernel@vger.kernel.org To: maxime.jayat@mobile-devices.fr Return-path: In-Reply-To: <20170221173551.3471-1-maxime.jayat@mobile-devices.fr> Sender: linux-kernel-owner@vger.kernel.org List-Id: netdev.vger.kernel.org From: Maxime Jayat Date: Tue, 21 Feb 2017 18:35:51 +0100 > Commit 34b88a68f26a ("net: Fix use after free in the recvmmsg exit path"), > changed the exit path of recvmmsg to always return the datagrams > variable and modified the error paths to set the variable to the error > code returned by recvmsg if necessary. > > However in the case sock_error returned an error, the error code was > then ignored, and recvmmsg returned 0. > > Change the error path of recvmmsg to correctly return the error code > of sock_error. > > The bug was triggered by using recvmmsg on a CAN interface which was > not up. Linux 4.6 and later return 0 in this case while earlier > releases returned -ENETDOWN. > > Fixes: 34b88a68f26a ("net: Fix use after free in the recvmmsg exit path") > Signed-off-by: Maxime Jayat Good catch, applied and queued up for -stable.