From patchwork Tue Apr 7 10:21:45 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg Kroah-Hartman X-Patchwork-Id: 228141 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=-9.9 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,URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable 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 800C5C2BB54 for ; Tue, 7 Apr 2020 10:29:23 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 5426B2074F for ; Tue, 7 Apr 2020 10:29:23 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1586255363; bh=IefxS/Yc5ROgBysnlD7RBJzc6vlR8Ndpi0VarpK9QKA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=U6+ZPacz0ObNp1kwn/RHuNWmaqgBsakHhSykjT5KAlsNh0fdvN2I9DjbdB/wivIJ7 7hUzdfSR2z2x4SB5N+gasYVSjdk1EfZ6i6EQmWd4Sttt+rNU7IdJuYMPMmwbUvmtF6 X7yz6V+ceg6E9ALt7/e+UghaaTAaME12Vfue5Fek= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728177AbgDGKXw (ORCPT ); Tue, 7 Apr 2020 06:23:52 -0400 Received: from mail.kernel.org ([198.145.29.99]:33822 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728572AbgDGKXv (ORCPT ); Tue, 7 Apr 2020 06:23:51 -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 5E7502082D; Tue, 7 Apr 2020 10:23:50 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1586255030; bh=IefxS/Yc5ROgBysnlD7RBJzc6vlR8Ndpi0VarpK9QKA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=BgEnh+cTklHT92fkelwkJ/4zloF+0WSb3Qwd+ophHzjXkABjuY0tfgBM4VbhlbMbj f1GApiSNW3rPnZLsvvkaPcGM9eTmeaIY2ru22nL4NvZGfv8mpS/71KB8g60ae2ZhbL 7inlMS4rtfFnpY93qwVJswm/MbxbKKRAFRuqA0VQ= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Bjorn Helgaas , Kees Cook , "Matthew Wilcox (Oracle)" , Sasha Levin Subject: [PATCH 5.4 12/36] XArray: Fix xa_find_next for large multi-index entries Date: Tue, 7 Apr 2020 12:21:45 +0200 Message-Id: <20200407101455.909577389@linuxfoundation.org> X-Mailer: git-send-email 2.26.0 In-Reply-To: <20200407101454.281052964@linuxfoundation.org> References: <20200407101454.281052964@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Matthew Wilcox (Oracle) [ Upstream commit bd40b17ca49d7d110adf456e647701ce74de2241 ] Coverity pointed out that xas_sibling() was shifting xa_offset without promoting it to an unsigned long first, so the shift could cause an overflow and we'd get the wrong answer. The fix is obvious, and the new test-case provokes UBSAN to report an error: runtime error: shift exponent 60 is too large for 32-bit type 'int' Fixes: 19c30f4dd092 ("XArray: Fix xa_find_after with multi-index entries") Reported-by: Bjorn Helgaas Reported-by: Kees Cook Signed-off-by: Matthew Wilcox (Oracle) Cc: stable@vger.kernel.org Signed-off-by: Sasha Levin --- lib/test_xarray.c | 18 ++++++++++++++++++ lib/xarray.c | 3 ++- 2 files changed, 20 insertions(+), 1 deletion(-) diff --git a/lib/test_xarray.c b/lib/test_xarray.c index 55c14e8c88591..8c7d7a8468b88 100644 --- a/lib/test_xarray.c +++ b/lib/test_xarray.c @@ -12,6 +12,9 @@ static unsigned int tests_run; static unsigned int tests_passed; +static const unsigned int order_limit = + IS_ENABLED(CONFIG_XARRAY_MULTI) ? BITS_PER_LONG : 1; + #ifndef XA_DEBUG # ifdef __KERNEL__ void xa_dump(const struct xarray *xa) { } @@ -959,6 +962,20 @@ static noinline void check_multi_find_2(struct xarray *xa) } } +static noinline void check_multi_find_3(struct xarray *xa) +{ + unsigned int order; + + for (order = 5; order < order_limit; order++) { + unsigned long index = 1UL << (order - 5); + + XA_BUG_ON(xa, !xa_empty(xa)); + xa_store_order(xa, 0, order - 4, xa_mk_index(0), GFP_KERNEL); + XA_BUG_ON(xa, xa_find_after(xa, &index, ULONG_MAX, XA_PRESENT)); + xa_erase_index(xa, 0); + } +} + static noinline void check_find_1(struct xarray *xa) { unsigned long i, j, k; @@ -1081,6 +1098,7 @@ static noinline void check_find(struct xarray *xa) for (i = 2; i < 10; i++) check_multi_find_1(xa, i); check_multi_find_2(xa); + check_multi_find_3(xa); } /* See find_swap_entry() in mm/shmem.c */ diff --git a/lib/xarray.c b/lib/xarray.c index 1d9fab7db8dad..acd1fad2e862a 100644 --- a/lib/xarray.c +++ b/lib/xarray.c @@ -1839,7 +1839,8 @@ static bool xas_sibling(struct xa_state *xas) if (!node) return false; mask = (XA_CHUNK_SIZE << node->shift) - 1; - return (xas->xa_index & mask) > (xas->xa_offset << node->shift); + return (xas->xa_index & mask) > + ((unsigned long)xas->xa_offset << node->shift); } /**