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=-9.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,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 75EF8C43215 for ; Tue, 3 Dec 2019 22:46:01 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 3F34F2084B for ; Tue, 3 Dec 2019 22:46:01 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1575413161; bh=vrTu9F5jC4RL5sr9hqkoyrHflN/833s3zkjY/EcRUUc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=wo31jnKY/xga+oAG2wMpSKn6X9/0/05Tc91OIf+AXvFhiNPsalg6+j4eVSqLlwHKd MDFAa7r8zP6hqq/mU1j65FsKLzzGgR8pS7l16HnssbKjgrdTlGjmMIF5uPRtNEkpSt v2wYnHNm9tlnjjXNAteuDDcw/hLfb4SIaH/1lH5Q= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729144AbfLCWp7 (ORCPT ); Tue, 3 Dec 2019 17:45:59 -0500 Received: from mail.kernel.org ([198.145.29.99]:34966 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728971AbfLCWp5 (ORCPT ); Tue, 3 Dec 2019 17:45:57 -0500 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 0C59720656; Tue, 3 Dec 2019 22:45:55 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1575413156; bh=vrTu9F5jC4RL5sr9hqkoyrHflN/833s3zkjY/EcRUUc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=rAa1MW81SFHQfsO6cuTn2mXooLt6sdMyBMwHp25dP+v5BvPO/v69/Xd3AUdfw6T4I fUjSimCHRW/wng4UkaRrppXN79z3XMvyPjPLDt06KtSYD9rHE2StkoImLjhdhBTcWw yc3SH8ml1uUr4Ikjdujk3ZsrzJoq1K6l603nvypI= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, "Matthew Wilcox (Oracle)" , Sasha Levin Subject: [PATCH 4.19 020/321] idr: Fix idr_alloc_u32 on 32-bit systems Date: Tue, 3 Dec 2019 23:31:26 +0100 Message-Id: <20191203223428.170816737@linuxfoundation.org> X-Mailer: git-send-email 2.24.0 In-Reply-To: <20191203223427.103571230@linuxfoundation.org> References: <20191203223427.103571230@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Matthew Wilcox (Oracle) [ Upstream commit b7e9728f3d7fc5c5c8508d99f1675212af5cfd49 ] Attempting to allocate an entry at 0xffffffff when one is already present would succeed in allocating one at 2^32, which would confuse everything. Return -ENOSPC in this case, as expected. Signed-off-by: Matthew Wilcox (Oracle) Signed-off-by: Sasha Levin --- lib/radix-tree.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/lib/radix-tree.c b/lib/radix-tree.c index bc03ecc4dfd2f..e5cab5c4e3830 100644 --- a/lib/radix-tree.c +++ b/lib/radix-tree.c @@ -2172,7 +2172,7 @@ void __rcu **idr_get_free(struct radix_tree_root *root, offset = radix_tree_find_next_bit(node, IDR_FREE, offset + 1); start = next_index(start, node, offset); - if (start > max) + if (start > max || start == 0) return ERR_PTR(-ENOSPC); while (offset == RADIX_TREE_MAP_SIZE) { offset = node->offset + 1; -- 2.20.1