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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 9C8A2C4332F for ; Mon, 28 Nov 2022 18:08:27 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234077AbiK1SIY (ORCPT ); Mon, 28 Nov 2022 13:08:24 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:45904 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234066AbiK1SIF (ORCPT ); Mon, 28 Nov 2022 13:08:05 -0500 Received: from mail-wm1-x332.google.com (mail-wm1-x332.google.com [IPv6:2a00:1450:4864:20::332]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id EBE9F59FF4 for ; Mon, 28 Nov 2022 09:52:21 -0800 (PST) Received: by mail-wm1-x332.google.com with SMTP id o7-20020a05600c510700b003cffc0b3374so8977974wms.0 for ; Mon, 28 Nov 2022 09:52:21 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bgdev-pl.20210112.gappssmtp.com; s=20210112; h=content-transfer-encoding:mime-version:message-id:date:subject:cc :to:from:from:to:cc:subject:date:message-id:reply-to; bh=Dibc9ypp0Q6XbTsifB1ue+YUADzHWkwbuvMtdIKjxQQ=; b=4im5lt765haSulIwEkgqdxEvE9h4M4wp3TRUgnIOejFUdCw9PcKIETCWvBbZya1Mcj FKAhuWdT1mO3VIPozkdTSmDp/6cobIzwyR5Q4WHikUhjgGH8VNirVgxqfllzFEHqjv0m mInR0irKqQC28i28arolf+j7do3FZTTZIuP3OD6Sxsel6/9Cvo3aEJzSsHIVhKg0kV82 8q6a6BOsP5VIHW8RjWohMsr5nxqpiYgIEDSJbXHubAUhUVKEkFUnHr9Qed4Kkzysxv5v XsiqXy69aPBl/YCEDZ9BB9j42AW0Hpd/2VbVQqbTMiD/UWK49lrceL1TyItgi+XoMEpD Q3+w== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=content-transfer-encoding:mime-version:message-id:date:subject:cc :to:from:x-gm-message-state:from:to:cc:subject:date:message-id :reply-to; bh=Dibc9ypp0Q6XbTsifB1ue+YUADzHWkwbuvMtdIKjxQQ=; b=R8Y3q8lTbRK/h2F/bkwTZlLmvwQvJqKAulsm5K++Dh4i/iHcNEh+6siuYuXgor6Ji7 /9OLmK0s7SrMdSgtEJBVvzwm8jaaYzK0XTJR2Cl9HrDWH1K7H0tHWQoT+qcML/ynaQFC eOyK//nfX4YRbLEQb4i0zVD2Qgkz4er4gMWcbF6O2WkkkMYBneEfwKe7owKmenHaozrr 4cVY9iaLm9NjUQdKY/qPJuv4UxKh7SDCACZMHZ9hRflInmaHCVwKqVI4pTRQFKVNblFL /k3NuwaFv9vs3f2hLxFXU6bLOuo5/+md0/3RgmXVP4Qht5a5EjlB/33tcLVDfLos2y10 Yovw== X-Gm-Message-State: ANoB5pkyhHohCAbwjOmgCyyUFKNay6SojchISSMTCRADfoECf/B+b3XT osBdVIwjCCDJsr/af9ZywSgalA== X-Google-Smtp-Source: AA0mqf6Fyo9ILJk30OroWysuv9NytlHqKSnd+1O6cWNLrD056ikszVIDzVixXavJV8LqsZMxZqJ/7A== X-Received: by 2002:a05:600c:3495:b0:3cf:a258:99b with SMTP id a21-20020a05600c349500b003cfa258099bmr38004715wmq.34.1669657939770; Mon, 28 Nov 2022 09:52:19 -0800 (PST) Received: from brgl-uxlite.home ([2a01:cb1d:334:ac00:791b:cf20:d3ea:d01]) by smtp.gmail.com with ESMTPSA id w7-20020a5d4b47000000b00242109cf587sm5828856wrs.28.2022.11.28.09.52.19 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 28 Nov 2022 09:52:19 -0800 (PST) From: Bartosz Golaszewski To: Kent Gibson , Linus Walleij , Andy Shevchenko Cc: linux-gpio@vger.kernel.org, linux-kernel@vger.kernel.org, Bartosz Golaszewski Subject: [PATCH v2 0/2] gpiolib: don't allow user-space to crash the kernel with hot-unplugs Date: Mon, 28 Nov 2022 18:52:12 +0100 Message-Id: <20221128175214.602612-1-brgl@bgdev.pl> X-Mailer: git-send-email 2.37.2 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Bartosz Golaszewski This is a second iteration of the changes that aim at fixing the situation in which the user-space can provoke a NULL-pointer derefence in the kernel when a GPIO device that's in use by user-space is removed. v1 -> v2: - add missing gdev->chip checks in patch 1/2 - add a second patch that protects the structures that can be accessed by user-space calls against concurrent removal Bartosz Golaszewski (2): gpiolib: cdev: fix NULL-pointer dereferences gpiolib: protect the GPIO device against being dropped while in use by user-space drivers/gpio/gpiolib-cdev.c | 240 +++++++++++++++++++++++++++++------- drivers/gpio/gpiolib.c | 3 + drivers/gpio/gpiolib.h | 5 + 3 files changed, 205 insertions(+), 43 deletions(-) -- 2.37.2