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[34.86.148.56]) by smtp.gmail.com with ESMTPSA id ny7-20020a056214398700b00686ac3226ccsm1300519qvb.114.2024.02.13.06.47.47 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 13 Feb 2024 06:47:47 -0800 (PST) Date: Tue, 13 Feb 2024 09:47:47 -0500 From: Willem de Bruijn To: Vadim Fedorenko , Vadim Fedorenko , Willem de Bruijn , Andy Lutomirski Cc: Vadim Fedorenko , Jakub Kicinski , "David S . Miller" , Willem de Bruijn , netdev@vger.kernel.org Message-ID: <65cb81133b8_2220892948a@willemb.c.googlers.com.notmuch> In-Reply-To: <20240213110428.1681540-1-vadfed@meta.com> References: <20240213110428.1681540-1-vadfed@meta.com> Subject: Re: [PATCH net v3] net-timestamp: make sk_tskey more predictable in error path Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Vadim Fedorenko wrote: > When SOF_TIMESTAMPING_OPT_ID is used to ambiguate timestamped datagrams, > the sk_tskey can become unpredictable in case of any error happened > during sendmsg(). Move increment later in the code and make decrement of > sk_tskey in error path. This solution is still racy in case of multiple > threads doing snedmsg() over the very same socket in parallel, but still > makes error path much more predictable. > > Fixes: 09c2d251b707 ("net-timestamp: add key to disambiguate concurrent datagrams") > Reported-by: Andy Lutomirski > Signed-off-by: Vadim Fedorenko Reviewed-by: Willem de Bruijn