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 775BFC4332F for ; Mon, 14 Nov 2022 12:55:11 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237498AbiKNMzK (ORCPT ); Mon, 14 Nov 2022 07:55:10 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:47492 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S237510AbiKNMzJ (ORCPT ); Mon, 14 Nov 2022 07:55:09 -0500 Received: from ams.source.kernel.org (ams.source.kernel.org [IPv6:2604:1380:4601:e00::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id AD031275E9 for ; Mon, 14 Nov 2022 04:55:07 -0800 (PST) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id 3ABD9B80EBC for ; Mon, 14 Nov 2022 12:55:06 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 7035AC43470; Mon, 14 Nov 2022 12:55:04 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1668430504; bh=S8n8NR0RAELzsKraZRDDZDen1H7Fgh/Gvz/w5CFFM7Q=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=jig5GIca+7H7nRhVM8KeztzZO8+c+Tdxh0knVhwaB+vvGTi1uLnt46TKgQ5jifak6 71ofxyWs1W0zlH5O59OIYflAdtsoxrd17Yde8J0WoizRLsXBfQFjZkWZkgONgCJvBw Xu9dmyLQrBa3RNQc9lPVLca8TzCiPRTHdoQC0XrA= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Wang Yufen , Eric Dumazet , "David S. Miller" , Sasha Levin Subject: [PATCH 5.15 030/131] net: tun: Fix memory leaks of napi_get_frags Date: Mon, 14 Nov 2022 13:44:59 +0100 Message-Id: <20221114124449.959978368@linuxfoundation.org> X-Mailer: git-send-email 2.38.1 In-Reply-To: <20221114124448.729235104@linuxfoundation.org> References: <20221114124448.729235104@linuxfoundation.org> User-Agent: quilt/0.67 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Wang Yufen [ Upstream commit 1118b2049d77ca0b505775fc1a8d1909cf19a7ec ] kmemleak reports after running test_progs: unreferenced object 0xffff8881b1672dc0 (size 232): comm "test_progs", pid 394388, jiffies 4354712116 (age 841.975s) hex dump (first 32 bytes): e0 84 d7 a8 81 88 ff ff 80 2c 67 b1 81 88 ff ff .........,g..... 00 40 c5 9b 81 88 ff ff 00 00 00 00 00 00 00 00 .@.............. backtrace: [<00000000c8f01748>] napi_skb_cache_get+0xd4/0x150 [<0000000041c7fc09>] __napi_build_skb+0x15/0x50 [<00000000431c7079>] __napi_alloc_skb+0x26e/0x540 [<000000003ecfa30e>] napi_get_frags+0x59/0x140 [<0000000099b2199e>] tun_get_user+0x183d/0x3bb0 [tun] [<000000008a5adef0>] tun_chr_write_iter+0xc0/0x1b1 [tun] [<0000000049993ff4>] do_iter_readv_writev+0x19f/0x320 [<000000008f338ea2>] do_iter_write+0x135/0x630 [<000000008a3377a4>] vfs_writev+0x12e/0x440 [<00000000a6b5639a>] do_writev+0x104/0x280 [<00000000ccf065d8>] do_syscall_64+0x3b/0x90 [<00000000d776e329>] entry_SYSCALL_64_after_hwframe+0x63/0xcd The issue occurs in the following scenarios: tun_get_user() napi_gro_frags() napi_frags_finish() case GRO_NORMAL: gro_normal_one() list_add_tail(&skb->list, &napi->rx_list); <-- While napi->rx_count < READ_ONCE(gro_normal_batch), <-- gro_normal_list() is not called, napi->rx_list is not empty <-- not ask to complete the gro work, will cause memory leaks in <-- following tun_napi_del() ... tun_napi_del() netif_napi_del() __netif_napi_del() <-- &napi->rx_list is not empty, which caused memory leaks To fix, add napi_complete() after napi_gro_frags(). Fixes: 90e33d459407 ("tun: enable napi_gro_frags() for TUN/TAP driver") Signed-off-by: Wang Yufen Reviewed-by: Eric Dumazet Signed-off-by: David S. Miller Signed-off-by: Sasha Levin --- drivers/net/tun.c | 1 + 1 file changed, 1 insertion(+) diff --git a/drivers/net/tun.c b/drivers/net/tun.c index 9909f430d723..4e77b269ef0a 100644 --- a/drivers/net/tun.c +++ b/drivers/net/tun.c @@ -1959,6 +1959,7 @@ static ssize_t tun_get_user(struct tun_struct *tun, struct tun_file *tfile, local_bh_disable(); napi_gro_frags(&tfile->napi); + napi_complete(&tfile->napi); local_bh_enable(); mutex_unlock(&tfile->napi_mutex); } else if (tfile->napi_enabled) { -- 2.35.1