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 4DE68C43603 for ; Wed, 4 Dec 2019 18:01:17 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 209B320863 for ; Wed, 4 Dec 2019 18:01:17 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1575482477; bh=vJW6LQs0JXd5WSJAwFOH6N0Stfj8RtMRcw+ztX7ByVU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=NU6HAgAEc2rQtsaGch3cTMwVCQLf/l/jhy4WS6yQ1Eq5BvzSRRmnQpJg8nhtxEnAX eBdObcK7D5lnhNY9XGXt4h9ZFnQsLCxnJUBDC0W1e6nrOSng3jlJd6+0A+0C4GET2I 1DUOAtP33obC8rRX2t4r6FWUqePNK4cIOFlK2ZWQ= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729539AbfLDSBP (ORCPT ); Wed, 4 Dec 2019 13:01:15 -0500 Received: from mail.kernel.org ([198.145.29.99]:41178 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729513AbfLDSBM (ORCPT ); Wed, 4 Dec 2019 13:01:12 -0500 Received: from localhost (unknown [217.68.49.72]) (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 A9DDB20659; Wed, 4 Dec 2019 18:01:11 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1575482472; bh=vJW6LQs0JXd5WSJAwFOH6N0Stfj8RtMRcw+ztX7ByVU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=KobLCTPutUWgaLV52i8Rdia0P8kpxUjjtcUHDnmjKVlneb/eDkA2jnUcR5gIilx2d GZ/FqqSYkv9Hkaguvox2DNsuEEoVsPhGyl+/2xAzMkZouHCvF/jWbvqPiY5OYUM84o S3dCn6/7F0MLemjvW0QbkMIYuQMdsFPya4ZyOe3I= 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 4.14 010/209] idr: Fix idr_alloc_u32 on 32-bit systems Date: Wed, 4 Dec 2019 18:53:42 +0100 Message-Id: <20191204175322.287481892@linuxfoundation.org> X-Mailer: git-send-email 2.24.0 In-Reply-To: <20191204175321.609072813@linuxfoundation.org> References: <20191204175321.609072813@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 d172f0341b807..ff00c816266b1 100644 --- a/lib/radix-tree.c +++ b/lib/radix-tree.c @@ -2184,7 +2184,7 @@ void __rcu **idr_get_free_cmn(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