From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id E753CC369D1 for ; Wed, 23 Apr 2025 13:57:54 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id E75146B00A5; Wed, 23 Apr 2025 09:57:53 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id DFA1E6B00A4; Wed, 23 Apr 2025 09:57:53 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id C9AA56B00A5; Wed, 23 Apr 2025 09:57:53 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0013.hostedemail.com [216.40.44.13]) by kanga.kvack.org (Postfix) with ESMTP id A97906B00A4 for ; Wed, 23 Apr 2025 09:57:53 -0400 (EDT) Received: from smtpin23.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay02.hostedemail.com (Postfix) with ESMTP id 8E9FF12089A for ; 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x86_64-pc-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-Stat-Signature: hm7fx3uxo1inzs7dbxkpf76bk549ouyh X-Rspamd-Queue-Id: B0D278000A X-Rspam-User: X-Rspamd-Server: rspam05 X-HE-Tag: 1745416671-218259 X-HE-Meta: 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 B2jRwwL1 qsx4H8AeGLhoQfXsdKU9Lm/8DWerRlJLowIG0hK5HS2yOCq/RV5Zw7a7weYYqbG67n1l8P3iyPqrKkZAvPC/u5nhAfbhIZBUyY5MgKAva0smm0EnbhTDSE06jBtpGif/xdAQZOveCRY8RCIjPpBMzTUhz7VNMMFjRgCWhydkmQP3MItPygIBZVJoQJ+ubDbIIFFseXJBuKY14YHQj12VkpgFwvv1ZRJujqyqEU4+VUZvFH3zNpVU1jeHvFzxD2u+8zQqD22Fb012qqceD11uR3Zil/bZClnb2WBS64ERFqK9W9Es2sKNjsjHM2pHYqXtrR/eQgGKW1c2xqRy/hjm7F67SYFhkL9bWJp1GD2o3Pfu+RiIZE/TSpMmUfzOu0SyKgSw8Ps7BPN0YY7cdkTLV5SJMH3RDLTIwtXTc X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Wed, 23 Apr 2025 12:37:46 +0100 Mykyta Yatsenko wrote: > > Does this fix any known runtime issue? If so, please fully describe this? > Not that I'm aware of. The issue could be found when trying to copy empty > user space string in BPF program (and relying on return value).There are > some usage of > `strncpy_from_user_nofault` in tracing subsystem, but I'm not sure how to > hit those code paths. > > Although your patch found a bug in the tracing subsystem, this wasn't the cause. It only cared if the read faulted or not. It was incorrectly checking for zero as non fault when in reality, it needed to check >= 0. With that fixed, it should work the same with or without this patch. -- Steve