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Content-Language: en-US To: Alejandro Colomar , Vincent Lefevre , libc-alpha@sourceware.org References: <9d7ca3d8-6998-e741-b669-03ef42bc99f1@gmail.com> <20230319230722.GD390223@zira.vinc17.org> From: Siddhesh Poyarekar In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-Spam-Status: No, score=-3030.6 required=5.0 tests=BAYES_00,DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,NICE_REPLY_A,RCVD_IN_DNSWL_NONE,RCVD_IN_MSPIKE_H2,SPF_HELO_NONE,SPF_PASS,TXREP autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on server2.sourceware.org List-Id: On 2023-03-20 08:17, Alejandro Colomar wrote: >>> if (checked) >>> sprintf (buf, "%s", s); >>> else >>> snprintf(buf, n, "%s", s); >>> >>> in particular in the cases where the format string is complex. > > That pattern looks like _FORTIFY_SOURCE, doesn't it? If so, the correct > action would be to call sprintf(3) and rely on the compiler to do the > checks. Yes the pattern is similar to __sprintf_chk, except that if the result string is larger, it will result in program abort while in the above pattern the string will get truncated. Sid