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 X-Spam-Level: X-Spam-Status: No, score=-0.9 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by aws-us-west-2-korg-lkml-1.web.codeaurora.org (Postfix) with ESMTP id C4FF3C433EF for ; Tue, 12 Jun 2018 22:40:47 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id B18A02086D for ; Tue, 12 Jun 2018 22:40:46 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=linaro.org header.i=@linaro.org header.b="OLTYh0Ca" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org B18A02086D Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=linaro.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S934956AbeFLWko (ORCPT ); Tue, 12 Jun 2018 18:40:44 -0400 Received: from mail-wm0-f65.google.com ([74.125.82.65]:55443 "EHLO mail-wm0-f65.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S934418AbeFLWkn (ORCPT ); Tue, 12 Jun 2018 18:40:43 -0400 Received: by mail-wm0-f65.google.com with SMTP id v16-v6so1406466wmh.5 for ; Tue, 12 Jun 2018 15:40:43 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; h=mime-version:from:date:message-id:subject:to:cc; bh=hx+vH43n5PZp+7APDmcf4yYkJPhesrm9wSMWB7GYEHU=; b=OLTYh0Ca+AOx3QiLpvNr97g9V/xMO/L1Dgs+bzG6y2BwFDSql/MCJSUysiqRSqbJtF zelOWvjBdfrr//3u/Wfyzzs5p6bCTWTFTTRc4Il4k9G0U5V+WfmhVxBkGCbwYcM/iJqM P7Rc/BpGPOLOrZ1uqNZlpe/7dFb+Bv5NtfCdQ= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:from:date:message-id:subject:to:cc; bh=hx+vH43n5PZp+7APDmcf4yYkJPhesrm9wSMWB7GYEHU=; b=GlrRjgcnnXIeSHtrOPmUehhQjiXNcxx6h7+EDJ88NQ09FSiwMdVgeEKyCFL8txDCCO 1sF7iHYiIB6NGU326b1uFf3B3+iR4dIr0tWRvfPaNdqjS60qeR2qQmCYgg1QEoK9JkmJ 0mNNjWA9G34/4iPROrJHUAhnHPrrFCaZrdMfV8ig293jiAZCtAzz7PG1kbhYcTkDnBfx FRdvSeuidYzDi2Oe3CxIjIFecARilF5p4jDO9p/SCF6V/w+YuoCTAuEmZh7CzPaB7X0E JfcUIEkhQieo8Sr9SLTuR2BlgyLhL7a0f9XWGyd9te6LYyDhtB3JekoabEyxwq7yIEv/ 2fiw== X-Gm-Message-State: APt69E3ag5iExZ49Hi96wA8I83k0FIllnTWYbUsHwww37c52AeZp4MTT UKq+GNDIrTa/CD4d4wD6V4WI3HqWM2ibBVTailHHUA== X-Google-Smtp-Source: ADUXVKLCj8hXGyqXJlcd2NZ7ATlt3LW0LtN+7/5up1MD9y5gtGNlVb01gvsKDcU74eiJXSkPErt7yYCf6lfIub3Ugwo= X-Received: by 2002:a1c:3c4:: with SMTP id 187-v6mr1681283wmd.96.1528843242241; Tue, 12 Jun 2018 15:40:42 -0700 (PDT) MIME-Version: 1.0 Received: by 2002:a1c:8ac3:0:0:0:0:0 with HTTP; Tue, 12 Jun 2018 15:40:41 -0700 (PDT) From: John Stultz Date: Tue, 12 Jun 2018 15:40:41 -0700 Message-ID: Subject: REGRESSION?: debugfs: inode: debugfs_create_dir uses mode permission from parent To: Thomas Richter Cc: Kees Cook , Greg Kroah-Hartman , lkml Content-Type: text/plain; charset="UTF-8" Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hey all, I noticed recently that linus/master (plus patches) stopped booting to UI on HiKey960, and I bisected the issue down to: 92170b62f1c1 ("debugfs: inode: debugfs_create_dir uses mode permission from parent") On the HiKey960 board, we mount debugfs via: mount debugfs /sys/kernel/debug /sys/kernel/debug mode=755 But since the change, it seems most of the nodes in /sys/kernel/debug are: drwx------ Which ends up breaking the egl library, keeping it from loading. This seems to be the expected behavior of the patch, but I'm surprised the mode override is now ignored. It seems like the potential fix here would be to set the /sys/kernel/debug dir to 755 prior to mounting? Or is there some other advised solution? thanks -john