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b=yKe3Oh6gdg531OfBw43CRNUKsQgWvXsUsbqL4REjhWRWV/EyQEdrVIPBBxhbQ6Wrl uuEd8GqnykwLaOZjANMsTohCJzwCacYB3UAVC5dchhbfYum2drYrs96DeGaFsN7WKW G7/mjy+gPsau7YI7w5oIeKkn7hbiOy2ShrvOTQZw= Received: from pek-lxu-l1.wrs.com ([111.198.228.153]) by newxmesmtplogicsvrszb9-1.qq.com (NewEsmtp) with SMTP id 162A8876; Thu, 11 Apr 2024 19:05:34 +0800 X-QQ-mid: xmsmtpt1712833534tlne241la Message-ID: X-QQ-XMAILINFO: OKKHiI6c9SH3AsUbxSTqAm1aPqHoG6wb2nOwfjMYc+bqlS1kwVIRXEAwYBBERt QbCiin0C5bVqMplz4dl9vTcDDMYP7hAZO+hM1n0jGudJ3wFMqw75nDi6Ar9VwEzqKOmhKLYLVoOr QaJNV+Fagrx4dx2jXdMq4Wl8Un5e6k1fYhhp+q7vg7mOqvraeER+n8UeEp8L/Z17RWCdJxdOqVIP swEgTIYpf6sXbmr7PUmc6leLos2wya5ZsXPnxUFjVYEB3hHbx9CQJmOGS53Zliwg+Kbf5EFtLHDI +zoFnq1w/z7BIe2DJ1KLADjm8xZ/KBxD/tlJvrGFnB2NIJDQJfXMjdTJ24SClRGqZo5a8fvwCuXA 7pTNbtT3F4/7V4wiazYeEpHPPIpp1oWd5OWJMRxtpnDq4MJdxrTV4UeJbYkyRKsd2NQcTLHqYrn7 XVgHOQDOnAw0YWdKi9QzUr3Tqm+l7ZplpSyNC7Qf5Mvj16FXNcSiM5qDG0mipJvQ+/KFS2pbc30x rLKHflaOisJm6dTtaMBbj3p5HEbI9bF588B47HxUazY71dRY9gjoki27OTtGNHEvKo5y2eTz6PV+ Z8XdHHOviEsCXaBhbhj9ODWa71pYo/yh3Ib1vqsTAD7Ybom8XeBpYRxQVV3xZIAbKfs92kFHvrD5 EuU3sOpgqvqRarVH90fcuTHyDm/uG9BAv2v10W+JVoIL3rSAiWl0VJ9YHHTExiHXB/OgBEQQpsX6 z6EUUBpL/jv7ioEgoIPe+xmp8PbdmpgeB50BU9Ivc5z9j+0nQ1sBL+NNF/4Y97qMLQAv9xtzxStf 4CmoNXVs7z8owUvuhzP0FDaOQfyE2Ayx7ZH+RlgGlBJiaPYewgvDCyPd2BVy+qC0e8buVqDX2BZl 50bjoHO6+5zsfWRTAAJMefByiS1A3kyxuRqPFtN9/POUtmFfEgzGdX6NPZN0xi+T30UqTJ1ltQ X-QQ-XMRINFO: NyFYKkN4Ny6FSmKK/uo/jdU= From: Edward Adam Davis To: yonghong.song@linux.dev Cc: andrii@kernel.org, ast@kernel.org, bpf@vger.kernel.org, daniel@iogearbox.net, eadavis@qq.com, haoluo@google.com, john.fastabend@gmail.com, jolsa@kernel.org, kpsingh@kernel.org, linux-kernel@vger.kernel.org, martin.lau@linux.dev, sdf@google.com, song@kernel.org, syzkaller-bugs@googlegroups.com Subject: Re: [PATCH] bpf: strnchr not suitable for getting NUL-terminator Date: Thu, 11 Apr 2024 19:05:19 +0800 X-OQ-MSGID: <20240411110518.1245753-2-eadavis@qq.com> X-Mailer: git-send-email 2.43.0 In-Reply-To: <4bfc3494-a3e9-4b4c-9d93-fa1049a10235@linux.dev> References: <4bfc3494-a3e9-4b4c-9d93-fa1049a10235@linux.dev> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit > > The strnchr() is not suitable for obtaining the end of a string with a length > > exceeding 1 and ending with a NUL character. > > Could you give more detailed explanation with specific examples? I think > strnchr() does the right thing here. Note that if fmt is not NULL, > strnchrnul() never returns NULL pointer so in the change below, > 'if (!fmt_end)' will be always false. My mistake, strnchr() work well. > > >