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 274ACC32796 for ; Tue, 23 Aug 2022 12:03:58 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S244525AbiHWMD4 (ORCPT ); Tue, 23 Aug 2022 08:03:56 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:48218 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S241742AbiHWMDF (ORCPT ); Tue, 23 Aug 2022 08:03:05 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id D2197DC5C5; Tue, 23 Aug 2022 02:36:57 -0700 (PDT) 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 dfw.source.kernel.org (Postfix) with ESMTPS id 7D74561389; Tue, 23 Aug 2022 09:36:57 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 43A0CC433D7; Tue, 23 Aug 2022 09:36:56 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1661247416; bh=3pYrimhcGr0K85s/IZAnpNsiTmUnQgIr+fgbMTw5icc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=SPPKMb3Sl8ztf/7hsjIpvB+tmWeSWl2W+bzHD1aIJgnKCt2ZPpk69oW7R5B+jFHav sRMJN92G+8AIid2iezBxCmjF9Ixp/qHOaMk2oW2Cc1PMEiVrEDgCkPumJUbX3L+Chz ToXHa8h3pric/iPm1p7Rl96EIefAZU2S2TPDFnM8= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Hou Tao , Yonghong Song , Martin KaFai Lau , Alexei Starovoitov Subject: [PATCH 5.10 029/158] bpf: Acquire map uref in .init_seq_private for sock local storage map iterator Date: Tue, 23 Aug 2022 10:26:01 +0200 Message-Id: <20220823080047.265635596@linuxfoundation.org> X-Mailer: git-send-email 2.37.2 In-Reply-To: <20220823080046.056825146@linuxfoundation.org> References: <20220823080046.056825146@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: Hou Tao commit 3c5f6e698b5c538bbb23cd453b22e1e4922cffd8 upstream. bpf_iter_attach_map() acquires a map uref, and the uref may be released before or in the middle of iterating map elements. For example, the uref could be released in bpf_iter_detach_map() as part of bpf_link_release(), or could be released in bpf_map_put_with_uref() as part of bpf_map_release(). So acquiring an extra map uref in bpf_iter_init_sk_storage_map() and releasing it in bpf_iter_fini_sk_storage_map(). Fixes: 5ce6e77c7edf ("bpf: Implement bpf iterator for sock local storage map") Signed-off-by: Hou Tao Acked-by: Yonghong Song Acked-by: Martin KaFai Lau Link: https://lore.kernel.org/r/20220810080538.1845898-4-houtao@huaweicloud.com Signed-off-by: Alexei Starovoitov Signed-off-by: Greg Kroah-Hartman --- net/core/bpf_sk_storage.c | 10 +++++++++- 1 file changed, 9 insertions(+), 1 deletion(-) --- a/net/core/bpf_sk_storage.c +++ b/net/core/bpf_sk_storage.c @@ -794,10 +794,18 @@ static int bpf_iter_init_sk_storage_map( { struct bpf_iter_seq_sk_storage_map_info *seq_info = priv_data; + bpf_map_inc_with_uref(aux->map); seq_info->map = aux->map; return 0; } +static void bpf_iter_fini_sk_storage_map(void *priv_data) +{ + struct bpf_iter_seq_sk_storage_map_info *seq_info = priv_data; + + bpf_map_put_with_uref(seq_info->map); +} + static int bpf_iter_attach_map(struct bpf_prog *prog, union bpf_iter_link_info *linfo, struct bpf_iter_aux_info *aux) @@ -843,7 +851,7 @@ static const struct seq_operations bpf_s static const struct bpf_iter_seq_info iter_seq_info = { .seq_ops = &bpf_sk_storage_map_seq_ops, .init_seq_private = bpf_iter_init_sk_storage_map, - .fini_seq_private = NULL, + .fini_seq_private = bpf_iter_fini_sk_storage_map, .seq_priv_size = sizeof(struct bpf_iter_seq_sk_storage_map_info), };