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 117B0C001DF for ; Fri, 20 Oct 2023 20:22:15 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230100AbjJTUWO (ORCPT ); Fri, 20 Oct 2023 16:22:14 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:35836 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230114AbjJTUWN (ORCPT ); Fri, 20 Oct 2023 16:22:13 -0400 Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 7E59AD65 for ; Fri, 20 Oct 2023 13:22:11 -0700 (PDT) Received: by smtp.kernel.org (Postfix) with ESMTPSA id BF7B6C433C8; Fri, 20 Oct 2023 20:22:10 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1697833331; bh=5M8B0xyUgQVkjXiJZ4F3G43uxlGkMisxy4syV+y45u0=; h=Subject:To:Cc:From:Date:From; b=b2pw6H2f1YSrrqIyDwcPmD2OAprCj9h3pUvH7r508xYpYqgDInPGnCLYk/aA9FSF1 zcclFamfboiQHQbc3SnKJ15zl0+GD1XSr3sx5tGjhGMNxGwF/1duXVXD0ev0hTIrYG EXIqqzJ2UJCigoIcQSt/0QGfRBXRNwlUm8ymgGJc= Subject: FAILED: patch "[PATCH] xfrm6: fix inet6_dev refcount underflow problem" failed to apply to 5.10-stable tree To: zhangchangzhong@huawei.com, lucien.xin@gmail.com, steffen.klassert@secunet.com Cc: From: Date: Fri, 20 Oct 2023 22:22:03 +0200 Message-ID: <2023102003-anagram-decency-29a0@gregkh> MIME-Version: 1.0 Content-Type: text/plain; charset=ANSI_X3.4-1968 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org The patch below does not apply to the 5.10-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to . To reproduce the conflict and resubmit, you may use the following commands: git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-5.10.y git checkout FETCH_HEAD git cherry-pick -x cc9b364bb1d58d3dae270c7a931a8cc717dc2b3b # git commit -s git send-email --to '' --in-reply-to '2023102003-anagram-decency-29a0@gregkh' --subject-prefix 'PATCH 5.10.y' HEAD^.. Possible dependencies: thanks, greg k-h ------------------ original commit in Linus's tree ------------------ >From cc9b364bb1d58d3dae270c7a931a8cc717dc2b3b Mon Sep 17 00:00:00 2001 From: Zhang Changzhong Date: Fri, 15 Sep 2023 19:20:41 +0800 Subject: [PATCH] xfrm6: fix inet6_dev refcount underflow problem There are race conditions that may lead to inet6_dev refcount underflow in xfrm6_dst_destroy() and rt6_uncached_list_flush_dev(). One of the refcount underflow bugs is shown below: (cpu 1) | (cpu 2) xfrm6_dst_destroy() | ... | in6_dev_put() | | rt6_uncached_list_flush_dev() ... | ... | in6_dev_put() rt6_uncached_list_del() | ... ... | xfrm6_dst_destroy() calls rt6_uncached_list_del() after in6_dev_put(), so rt6_uncached_list_flush_dev() has a chance to call in6_dev_put() again for the same inet6_dev. Fix it by moving in6_dev_put() after rt6_uncached_list_del() in xfrm6_dst_destroy(). Fixes: 510c321b5571 ("xfrm: reuse uncached_list to track xdsts") Signed-off-by: Zhang Changzhong Reviewed-by: Xin Long Signed-off-by: Steffen Klassert diff --git a/net/ipv6/xfrm6_policy.c b/net/ipv6/xfrm6_policy.c index 188224a76685..45d0f9a8b28c 100644 --- a/net/ipv6/xfrm6_policy.c +++ b/net/ipv6/xfrm6_policy.c @@ -117,10 +117,10 @@ static void xfrm6_dst_destroy(struct dst_entry *dst) { struct xfrm_dst *xdst = (struct xfrm_dst *)dst; - if (likely(xdst->u.rt6.rt6i_idev)) - in6_dev_put(xdst->u.rt6.rt6i_idev); dst_destroy_metrics_generic(dst); rt6_uncached_list_del(&xdst->u.rt6); + if (likely(xdst->u.rt6.rt6i_idev)) + in6_dev_put(xdst->u.rt6.rt6i_idev); xfrm_dst_destroy(xdst); }