From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Google-Smtp-Source: AIpwx4/6np/xPBvntSFPHKGlgEw4rRi901Gt7t4TMfMqQxwDuitku8jnQW+HNcdKyE4tgXSViRTU ARC-Seal: i=1; a=rsa-sha256; t=1523399900; cv=none; d=google.com; s=arc-20160816; b=OnFihCFqlMGQFTIgXDJE82VugVLUyIgnMb6Y/VW7TP2+/UEFu6sAXL+5FhOIqpsPC7 42/exmdE+wtYbT5HeM1qGQf1ZZ36A8+Vr60fCu2Bi4rZiwIvi+wtharymPpyJjG+O3mM /2P71V86Zgug2F67Ntq3+GAlVcdnO3vsOoQ2F3ix8XMcXuoNlPvYqxSRhHE0dOKnt5Uc 1/NdoY3SQPIZmAsneARL11vn69ZZqD8ZAXvuGUrtgCZTwzp8VlUgyF5TDbf3IOsTg14f V9KjJYC9d9WpkJdDGyFLJTr+QY18jywS9IOzNUxuHbGMb410E8IQI0LLYCnwQOsBDyg6 7NcQ== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=mime-version:user-agent:references:in-reply-to:message-id:date :subject:cc:to:from:arc-authentication-results; bh=ge3mPjeUEnq5PZlahWSwh0O3OWUO/Ydwu6X0MiS86vw=; b=dR1e+yJ0UzyUjT3p2LhX87ZFModSA2duvQ4KKI7E87QRKZayYTYvucQ2vKJQynlmUJ 3aTp1CvfkPpeaGkjsZHflr9+nnQs2u3tdsc3nyStIHBovZjRXjYUrKVvvJGALr3UbH4f wgTKT9Qh+n3a+dNjbjbktlmeY/noi2hV9G49i6qnrJQ/wl/m2yv8g0Iq2i2WL7sd474k zgWJ+RQmMTMNLqe1WhUBGVwgkemXjBNUxr6bOil8DFxGe5gsgvf+ZQAvNydFh4o0m2QQ nGxKodjQ2LLbdp4brgIvpVU7MciUt9GjYO/w3v55b4uvYjvSdWikdTtQVMaHuN9Wa9ir aA/A== ARC-Authentication-Results: i=1; mx.google.com; spf=softfail (google.com: domain of transitioning gregkh@linuxfoundation.org does not designate 90.92.61.202 as permitted sender) smtp.mailfrom=gregkh@linuxfoundation.org Authentication-Results: mx.google.com; spf=softfail (google.com: domain of transitioning gregkh@linuxfoundation.org does not designate 90.92.61.202 as permitted sender) smtp.mailfrom=gregkh@linuxfoundation.org From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Craig Dillabaugh , Jamal Hadi Salim , "David S. Miller" Subject: [PATCH 4.14 104/138] net sched actions: fix dumping which requires several messages to user space Date: Wed, 11 Apr 2018 00:24:54 +0200 Message-Id: <20180410212914.274790641@linuxfoundation.org> X-Mailer: git-send-email 2.17.0 In-Reply-To: <20180410212902.121524696@linuxfoundation.org> References: <20180410212902.121524696@linuxfoundation.org> User-Agent: quilt/0.65 X-stable: review MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 X-getmail-retrieved-from-mailbox: INBOX X-GMAIL-LABELS: =?utf-8?b?IlxcU2VudCI=?= X-GMAIL-THRID: =?utf-8?q?1597400153731397054?= X-GMAIL-MSGID: =?utf-8?q?1597400574240219292?= X-Mailing-List: linux-kernel@vger.kernel.org List-ID: 4.14-stable review patch. If anyone has any objections, please let me know. ------------------ From: Craig Dillabaugh [ Upstream commit 734549eb550c0c720bc89e50501f1b1e98cdd841 ] Fixes a bug in the tcf_dump_walker function that can cause some actions to not be reported when dumping a large number of actions. This issue became more aggrevated when cookies feature was added. In particular this issue is manifest when large cookie values are assigned to the actions and when enough actions are created that the resulting table must be dumped in multiple batches. The number of actions returned in each batch is limited by the total number of actions and the memory buffer size. With small cookies the numeric limit is reached before the buffer size limit, which avoids the code path triggering this bug. When large cookies are used buffer fills before the numeric limit, and the erroneous code path is hit. For example after creating 32 csum actions with the cookie aaaabbbbccccdddd $ tc actions ls action csum total acts 26 action order 0: csum (tcp) action continue index 1 ref 1 bind 0 cookie aaaabbbbccccdddd ..... action order 25: csum (tcp) action continue index 26 ref 1 bind 0 cookie aaaabbbbccccdddd total acts 6 action order 0: csum (tcp) action continue index 28 ref 1 bind 0 cookie aaaabbbbccccdddd ...... action order 5: csum (tcp) action continue index 32 ref 1 bind 0 cookie aaaabbbbccccdddd Note that the action with index 27 is omitted from the report. Fixes: 4b3550ef530c ("[NET_SCHED]: Use nla_nest_start/nla_nest_end")" Signed-off-by: Craig Dillabaugh Acked-by: Jamal Hadi Salim Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- net/sched/act_api.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) --- a/net/sched/act_api.c +++ b/net/sched/act_api.c @@ -133,8 +133,10 @@ static int tcf_dump_walker(struct tcf_id continue; nest = nla_nest_start(skb, n_i); - if (!nest) + if (!nest) { + index--; goto nla_put_failure; + } err = tcf_action_dump_1(skb, p, 0, 0); if (err < 0) { index--;