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=-9.0 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_PASS,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id B56ADC43381 for ; Fri, 22 Mar 2019 11:25:47 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 851E12192D for ; Fri, 22 Mar 2019 11:25:47 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1553253947; bh=XMZ4XN4kUDEllxWJ0IuHS++PhDlbBi+TdZnjWGdqprY=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=QryomKTFzyrh+327N/Tkzcu0E3yaV05Eu80x4DaTWVEctBfvapJ/Wrx1lsZH7Qi5r mzwmLRgHOqxVsvNU8tXKUT+dy/3AATaMwU8o4kGWjS0z8FQRHtvPVIfkHIGAINbQGB 18sytLuOY7bvfgkruORos9PgrKao6v2wwEg9rLrA= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728241AbfCVLZp (ORCPT ); Fri, 22 Mar 2019 07:25:45 -0400 Received: from mail.kernel.org ([198.145.29.99]:53256 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729329AbfCVLZo (ORCPT ); Fri, 22 Mar 2019 07:25:44 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id B4DAE20657; Fri, 22 Mar 2019 11:25:43 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1553253944; bh=XMZ4XN4kUDEllxWJ0IuHS++PhDlbBi+TdZnjWGdqprY=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=dFuxjHaUuRFQWDln8ivWtsXTdSOajAw/Av4MXjYSxLa2PxjvU+G8LidKEgluEQTq2 wmxq5k0mQhxGgpNdhWr8UC0srdL2VneuqdGXlBPNj84b9E+J9VNRIo28aVOXp7bzU0 SCTHjXIYHjz1Lo1iQ42LAAshzhFkGJ/TZxsJV9DU= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, David Howells , James Morris , Sasha Levin Subject: [PATCH 3.18 102/134] assoc_array: Fix shortcut creation Date: Fri, 22 Mar 2019 12:15:15 +0100 Message-Id: <20190322111217.548351431@linuxfoundation.org> X-Mailer: git-send-email 2.21.0 In-Reply-To: <20190322111210.465931067@linuxfoundation.org> References: <20190322111210.465931067@linuxfoundation.org> User-Agent: quilt/0.65 X-stable: review X-Patchwork-Hint: ignore MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org 3.18-stable review patch. If anyone has any objections, please let me know. ------------------ [ Upstream commit bb2ba2d75a2d673e76ddaf13a9bd30d6a8b1bb08 ] Fix the creation of shortcuts for which the length of the index key value is an exact multiple of the machine word size. The problem is that the code that blanks off the unused bits of the shortcut value malfunctions if the number of bits in the last word equals machine word size. This is due to the "<<" operator being given a shift of zero in this case, and so the mask that should be all zeros is all ones instead. This causes the subsequent masking operation to clear everything rather than clearing nothing. Ordinarily, the presence of the hash at the beginning of the tree index key makes the issue very hard to test for, but in this case, it was encountered due to a development mistake that caused the hash output to be either 0 (keyring) or 1 (non-keyring) only. This made it susceptible to the keyctl/unlink/valid test in the keyutils package. The fix is simply to skip the blanking if the shift would be 0. For example, an index key that is 64 bits long would produce a 0 shift and thus a 'blank' of all 1s. This would then be inverted and AND'd onto the index_key, incorrectly clearing the entire last word. Fixes: 3cb989501c26 ("Add a generic associative array implementation.") Signed-off-by: David Howells Signed-off-by: James Morris Signed-off-by: Sasha Levin --- lib/assoc_array.c | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-) diff --git a/lib/assoc_array.c b/lib/assoc_array.c index 0d122543bd63..1db287fffb67 100644 --- a/lib/assoc_array.c +++ b/lib/assoc_array.c @@ -780,9 +780,11 @@ all_leaves_cluster_together: new_s0->index_key[i] = ops->get_key_chunk(index_key, i * ASSOC_ARRAY_KEY_CHUNK_SIZE); - blank = ULONG_MAX << (level & ASSOC_ARRAY_KEY_CHUNK_MASK); - pr_devel("blank off [%zu] %d: %lx\n", keylen - 1, level, blank); - new_s0->index_key[keylen - 1] &= ~blank; + if (level & ASSOC_ARRAY_KEY_CHUNK_MASK) { + blank = ULONG_MAX << (level & ASSOC_ARRAY_KEY_CHUNK_MASK); + pr_devel("blank off [%zu] %d: %lx\n", keylen - 1, level, blank); + new_s0->index_key[keylen - 1] &= ~blank; + } /* This now reduces to a node splitting exercise for which we'll need * to regenerate the disparity table. -- 2.19.1