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b=VB5BaOgfyrAXSSi5m4EFQEb8Aj XrLFenIf+dBNd7uulUxeTn5poyR8aKCBNf54YRhg9Au+AIoSbEmXOo4Fy1ZLZhY2qvy3C3mwRDOkt y0HRmTY10nZdGq5TMRO0WebFuOAfzbU+/InME9Y662/bkW+dkFZ4hvnmyRpDuiAT90FNQ3ZZIt4Hr zIErHqz6AVZUyvQ9cVL3e6zh5WjVNIaoPDxH/jDidiPG+Ef2BQP7jHMK81OWSFFqPnqe3nJb6k7pe gQKyEmnExlD2O5yXc6r+6F5wrMnQHtCD9x3tZYvjNKzcITGKVUjFoFLyhOFr7Bq/WGPlDaDSV5QWP SOzwRwdA==; Received: from [179.193.2.40] (helo=[192.168.15.100]) by fanzine2.igalia.com with esmtpsa (Cipher TLS1.3:ECDHE_X25519__RSA_PSS_RSAE_SHA256__AES_128_GCM:128) (Exim) id 1wPRL2-003P3J-6r; Tue, 19 May 2026 22:46:52 +0200 Message-ID: <186dbf31-e5a8-4bb5-a392-0bf3cb4127cb@igalia.com> Date: Tue, 19 May 2026 17:46:44 -0300 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH 3/6] string: Introduce strtostr() for safe and performance string copies To: Linus Torvalds Cc: David Laight , Peter Zijlstra , Juri Lelli , Vincent Guittot , Steven Rostedt , Christian Brauner , Kees Cook , Shuah Khan , willy@infradead.org, mathieu.desnoyers@efficios.com, akpm@linux-foundation.org, Yafang Shao , andrii.nakryiko@gmail.com, arnaldo.melo@gmail.com, Petr Mladek , linux-kernel@vger.kernel.org, kernel-dev@igalia.com, linux-mm@kvack.org, linux-api@vger.kernel.org References: <20260517-tonyk-long_name-v1-0-3c282eaa91e2@igalia.com> <20260517-tonyk-long_name-v1-3-3c282eaa91e2@igalia.com> <20260517223419.3262de7c@pumpkin> Content-Language: en-US From: =?UTF-8?Q?Andr=C3=A9_Almeida?= In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit X-Rspamd-Server: rspam12 X-Rspamd-Queue-Id: 18F1814000F X-Stat-Signature: whta8c4cf1jzhxe4kffwc7baqnsb3dyy X-Rspam-User: X-HE-Tag: 1779223633-557503 X-HE-Meta: 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 +uH6Ahzo BpWIGvJbx0+2k/cDDwZg7baBaC5clV/dcB8FuNhC68uSXAke3NHS2YQzQIaQT9vMhpiCnnHfzHYc+9fzx2uPj+r4OyzcjvyY37vvOAkI3SDcf+OZRGiE/Rh32/USSi5ghCjKfk3pqzmUQyiTt/smIWFWTPl1ruMaQZzXP/Lju1hXAuiEEoB1eh5wEV6rNAtSkYh6ZqSIhuEAiQjLIZLEgM+liml3sduD3lWZqi8cVEBlWNk5UuIr6jYSRchdCEmRCZHhwnd++i72g4iLEJNEJ2vex9M3kNRUaEJp4sKMYpktpP+wjr/WSXXYdlLh/Plhq2RdU3IoNl6QJ2C2e7rj1k8z6WizM6kzDcKK+E9en33XJAHDnRmNeDQxA7o/Hqr7SSrnFNfMJuZOpf8gHMXKIOjDqKFlkx3nKSO24OoHqt1owo8f3Ymte/Zczx1sv/XOT284x Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: Em 19/05/2026 17:37, Linus Torvalds escreveu: > On Mon, 18 May 2026 at 09:37, André Almeida wrote: >> >> The problem is that as I'm expanding current->comm, the source buffer >> might be bigger than destination, and when we truncate the string, it >> won't have the termination NUL byte. So we need an extra dest[len-1] = >> \0 after the memcpy. > > What's wrong with just using strscpy() with 'len' being min(srcsize,dstsize)? > Well, I thought that strscpy() was too expensive for the trace use case, but I'm happy to use it in the v2 if it's ok.