From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1) server-digest SHA256) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 889C060A3835 for ; Thu, 5 Nov 2026 19:29:58 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key, unprotected) header.d=lists.infradead.org header.i=@lists.infradead.org header.a=rsa-sha256 header.s=bombadil.20210309 header.b=Ku2ikHCP; dkim=pass (2048-bit key, unprotected) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=dlMl9M/r DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:Reply-To:List-Subscribe: List-Help:List-Post:List-Archive:List-Unsubscribe:List-Id:Date: Content-Transfer-Encoding:Content-Type:References:In-Reply-To:Cc:To:Subject: From:Message-ID:MIME-Version:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Unsubscribe-Post:List-Owner; bh=2jOjP+w+HiO6pPFlf+UtXLVpbUo8fVoVCMG/gzgxPSY=; b=Ku2ikHCP6ivys390X0vV+E3thJ 1RwNOZJPa2GoEbUvzwf0A080Ypw1si5/AqvB8b3Gv+m13Xu9oV1Nj9/1eY3uIrG2XdCeLQjXpOnPM 8uUtZ3Sm8ODacQV4Bt+McKqhvzGt843nFZ/zd8kaFnRvgv88WV5FVqtrfhI9lobSaeivKuOOrSmn9 PjaOWixtv2wSv4+aukdYBZAC5EeClhdioKEherkOCkdoW9Qsx1p9E9AEWMiurotQC4hJjZbphjrY5 hScmuspZO7Dg4agmFDRG+hfa5wxJpxxUI9Jio1OS8m0LUZsNdGq/cxktcNiYgHZND6t4rph4tVq11 dhA9XZaw==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.100.1 #2 (Red Hat Linux)) id 1xP39q-0000000AKby-0DQn; Thu, 05 Nov 2026 19:29:58 +0000 Received: from tor.source.kernel.org ([172.105.4.254]) by bombadil.infradead.org with esmtps (Exim 4.100.1 #2 (Red Hat Linux)) id 1xP39D-0000000AKG8-0GFW for kexec@lists.infradead.org; Thu, 05 Nov 2026 19:29:19 +0000 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) by tor.source.kernel.org (Postfix) with ESMTP id 8159B6015B; Thu, 5 Nov 2026 19:29:18 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id C1D611F00919; Thu, 5 Nov 2026 19:29:16 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1793906958; bh=2jOjP+w+HiO6pPFlf+UtXLVpbUo8fVoVCMG/gzgxPSY=; h=From:Subject:Reply-To:To:Cc:In-Reply-To:References:Date; b=dlMl9M/rPNxEZu6+Ri3OXa9FPI28S+nKPOVBymLRvAUIbEdACYesn7GaasG71a1si Jkdk1nguj1FW0I6rEhmRyL6rCf6iGgz0RsNmgA2Aax7T6dfl/bLd0reMK3dxl47No2 cZOPksbLnHyzXhnv8X6aqtgNCaUxaH8zvMCcgysEle4NYPvSVucRgboVQsljfhslI1 t38Nm+rBEGJUAgtRVOrBLiUgvSsBb85o5UOO6lhjVE/GMpZGzwjSdxGKJTR11kjWCO BXN98+TIo2Yx9dB8Tl/s4rDba6W5uK4F2hW8KmNF5r4lJJBlBYlOLW1lUh+7tDsUMj MzavIifWHwTQQ== Message-ID: From: sashiko-bot@kernel.org Subject: Re: [PATCH RESEND v2 14/51] proc: sysctl: don't stop readdir at an entry that is being unregistered To: "Christian Brauner" Cc: "Linus Torvalds" , "Jann Horn" , "Josef Bacik" , "Chris Mason" , "Jeff Layton" , NeilBrown , "Eric Dumazet" , "Thomas Gleixner" , "Al Viro" , "Jonathan Corbet" , "Christoph Hellwig" , "Greg Kroah-Hartman" , "Joel Granados" , "Kees Cook" , "Jan Kara" , "Jan Kara" , linux-s390@vger.kernel.org, coreteam@netfilter.org, kexec@lists.infradead.org, linux-pci@vger.kernel.org, linux-hwmon@vger.kernel.org, linux-usb@vger.kernel.org, samba-technical@lists.samba.org, linux-m68k@lists.linux-m68k.org, linux-serial@vger.kernel.org, "Takashi Iwai" , linux-ext4@vger.kernel.org, "Chuck Lever" , tytso@mit.edu, "Heiko Carstens" , "Vasily Gorbik" , "Alexander Gordeev" , "Christian Borntraeger" In-Reply-To: <20261104-work-procfs-bugfixes-v2-14-021c84d852e0@kernel.org> References: <20261104-work-procfs-bugfixes-v2-0-021c84d852e0@kernel.org> <20261104-work-procfs-bugfixes-v2-14-021c84d852e0@kernel.org> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Date: Thu, 05 Nov 2026 19:29:16 +0000 X-BeenThere: kexec@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Archive: List-Post: List-Help: List-Subscribe: , Reply-To: sashiko-reviews@lists.linux.dev Sender: "kexec" X-Spam-Status: No, score=-10.9 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS autolearn=ham autolearn_force=no version=4.0.1 X-Spam-Checker-Version: SpamAssassin 4.0.1 (2024-03-26) on aws-us-west-2-korg-listserv-alma10-1 X-Archived-By: > proc_sys_fill_cache() creates the inode of an entry that has no dentry > yet. Since ace0c791e6c3 ("proc/sysctl: Don't grab i_lock under > sysctl_lock.") proc_sys_make_inode() refuses to do that once the table > is being unregistered and fails with -ENOENT. readdir takes every table > it lists into use and unregister_sysctl_table() marks the table as > being unregistered before it waits for readdir to let go of it. So an > entry that is unregistered right then makes proc_sys_fill_cache() fail, > proc_sys_readdir() stops there and returns 0. If that getdents64() call > hadn't emitted anything before that entry userspace sees the end of the > directory and never gets the entries behind it. A listing of > /proc/sys/net/ipv6/conf can end early that way while a device goes > away. >=20 > So skip an entry whose table is being unregistered, like readdir > already skips a link it can't follow. Lookup treats such an entry as > gone too since ea5751ccd665 ("proc/sysctl: don't return ENOMEM on > lookup when a table is unregistering"). >=20 > Fixes: ace0c791e6c3 ("proc/sysctl: Don't grab i_lock under sysctl_lock.") > Cc: stable@vger.kernel.org > Signed-off-by: Christian Brauner (Amutable) Sashiko has reviewed this patch and found no issues. --=20 Sashiko AI review =C2=B7 https://sashiko.dev/#/patchset/20261104-work-procf= s-bugfixes-v2-0-021c84d852e0@kernel.org?part=3D14