From patchwork Tue May 9 13:18:57 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Eric Dumazet X-Patchwork-Id: 13235807 X-Patchwork-Delegate: kuba@kernel.org Received: from lindbergh.monkeyblade.net (lindbergh.monkeyblade.net [23.128.96.19]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 874A3182AE for ; Tue, 9 May 2023 13:19:04 +0000 (UTC) Received: from mail-yb1-xb49.google.com (mail-yb1-xb49.google.com [IPv6:2607:f8b0:4864:20::b49]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 99B0C1BE4 for ; Tue, 9 May 2023 06:19:02 -0700 (PDT) Received: by mail-yb1-xb49.google.com with SMTP id 3f1490d57ef6-b8f46dc51bdso12752610276.3 for ; Tue, 09 May 2023 06:19:02 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20221208; t=1683638342; x=1686230342; h=content-transfer-encoding:cc:to:from:subject:message-id :mime-version:date:from:to:cc:subject:date:message-id:reply-to; bh=zcDLJjD+xErZe10CJAjjRbsBCbBOcSySl03HFJFeYLU=; b=BGGPs2la3Kga/FcqcyYLsvpVALGPbHslOLwcDrhEIvvhxxICKuu2TgIOXTN9HUYkYE GM+C3u7VhJM3NTerk9tIL9LJRF7IuLkqi9xYVOZZUe8IQptkB380DIqRNO04psCB0/rp pN8gFsGQCPqWLBXqmaGYqk75fVyiQrxdZcdM/U798osKwyENwgU+5KQIpvd5F3keXx0q scgHGpTwFlDqowARXsLuSIIpMeIHIljDV9NZ9VWzIj5Len6hpRkTD8tvfyFP4tVhC3jJ VZq1j++4Jid6IQi075OXdNUPiXVJJeAthijbrYPX6GFozLARaYMY5NllANwgbBTRGVxT EIRQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1683638342; x=1686230342; h=content-transfer-encoding:cc:to:from:subject:message-id :mime-version:date:x-gm-message-state:from:to:cc:subject:date :message-id:reply-to; bh=zcDLJjD+xErZe10CJAjjRbsBCbBOcSySl03HFJFeYLU=; b=GjF6a4ViNWL5n+RCW4cVkn65Xy3kQtAkSpV36dktXnal3fAUurr+TxGq3Zc/V7Is4c itnvwVj0mXYL2dP8hywvZU+KQa10kJJzRzlqpRTJrNVruB2i2e3gceNOynCugPyUNEzF QVqrqtq2IgWgPA6lDieR4GlxttJ/HGFf4SPtD3QcWFbDhhdsK1/jEWvpki4Y2xY0+1yK lFTc9kazA3Li1wJkwcP0njkzoo7moqa8DCWHHMscXbfaqe0tgHTqcjQD+XFUYSO/8BRD p5ntKCGXMnL+DVjKznx/wN+ERsVrXEYKo8+vx6A6irHHZeTiZdcrSLIxvL8ukclBN2Fz fKXw== X-Gm-Message-State: AC+VfDwd2BVdCxPDwwWVMRemHlzZX2HMMrWtX9tT7vxfWnLBbjbw1xlr vTkD57Xtd4Lr8Udkzfq2o20JNTqZGn2OiA== X-Google-Smtp-Source: ACHHUZ4EqTq5njvi7+UTnvlArUCzzPn7lsWM2F7gKC5oRoQE+2n/ZLpNtvvmzzEVGyMdTIJu0v27HwD/b+L+5A== X-Received: from edumazet1.c.googlers.com ([fda3:e722:ac3:cc00:2b:7d90:c0a8:395a]) (user=edumazet job=sendgmr) by 2002:a05:6902:1021:b0:ba1:b908:364c with SMTP id x1-20020a056902102100b00ba1b908364cmr8824076ybt.12.1683638341776; Tue, 09 May 2023 06:19:01 -0700 (PDT) Date: Tue, 9 May 2023 13:18:57 +0000 Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 X-Mailer: git-send-email 2.40.1.521.gf1e218fcd8-goog Message-ID: <20230509131857.2947439-1-edumazet@google.com> Subject: [PATCH net] net: add vlan_get_protocol_and_depth() helper From: Eric Dumazet To: "David S . Miller" , Jakub Kicinski , Paolo Abeni Cc: netdev@vger.kernel.org, eric.dumazet@gmail.com, Eric Dumazet , syzbot , " =?utf-8?q?Toke_H=C3=B8iland-J=C3=B8rgensen?= " , Willem de Bruijn X-Spam-Status: No, score=-9.6 required=5.0 tests=BAYES_00,DKIMWL_WL_MED, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,RCVD_IN_DNSWL_NONE, SPF_HELO_NONE,SPF_PASS,T_SCC_BODY_TEXT_LINE,USER_IN_DEF_DKIM_WL autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net X-Patchwork-Delegate: kuba@kernel.org Before blamed commit, pskb_may_pull() was used instead of skb_header_pointer() in __vlan_get_protocol() and friends. Few callers depended on skb->head being populated with MAC header, syzbot caught one of them (skb_mac_gso_segment()) Add vlan_get_protocol_and_depth() to make the intent clearer and use it where sensible. This is a more generic fix than commit e9d3f80935b6 ("net/af_packet: make sure to pull mac header") which was dealing with a similar issue. kernel BUG at include/linux/skbuff.h:2655 ! invalid opcode: 0000 [#1] SMP KASAN CPU: 0 PID: 1441 Comm: syz-executor199 Not tainted 6.1.24-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/14/2023 RIP: 0010:__skb_pull include/linux/skbuff.h:2655 [inline] RIP: 0010:skb_mac_gso_segment+0x68f/0x6a0 net/core/gro.c:136 Code: fd 48 8b 5c 24 10 44 89 6b 70 48 c7 c7 c0 ae 0d 86 44 89 e6 e8 a1 91 d0 00 48 c7 c7 00 af 0d 86 48 89 de 31 d2 e8 d1 4a e9 ff <0f> 0b 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 55 48 89 e5 41 RSP: 0018:ffffc90001bd7520 EFLAGS: 00010286 RAX: ffffffff8469736a RBX: ffff88810f31dac0 RCX: ffff888115a18b00 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffffc90001bd75e8 R08: ffffffff84697183 R09: fffff5200037adf9 R10: 0000000000000000 R11: dffffc0000000001 R12: 0000000000000012 R13: 000000000000fee5 R14: 0000000000005865 R15: 000000000000fed7 FS: 000055555633f300(0000) GS:ffff8881f6a00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000020000000 CR3: 0000000116fea000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: [] __skb_gso_segment+0x32d/0x4c0 net/core/dev.c:3419 [] skb_gso_segment include/linux/netdevice.h:4819 [inline] [] validate_xmit_skb+0x3aa/0xee0 net/core/dev.c:3725 [] __dev_queue_xmit+0x1332/0x3300 net/core/dev.c:4313 [] dev_queue_xmit+0x17/0x20 include/linux/netdevice.h:3029 [] packet_snd net/packet/af_packet.c:3111 [inline] [] packet_sendmsg+0x49d2/0x6470 net/packet/af_packet.c:3142 [] sock_sendmsg_nosec net/socket.c:716 [inline] [] sock_sendmsg net/socket.c:736 [inline] [] __sys_sendto+0x472/0x5f0 net/socket.c:2139 [] __do_sys_sendto net/socket.c:2151 [inline] [] __se_sys_sendto net/socket.c:2147 [inline] [] __x64_sys_sendto+0xe5/0x100 net/socket.c:2147 [] do_syscall_x64 arch/x86/entry/common.c:50 [inline] [] do_syscall_64+0x2f/0x50 arch/x86/entry/common.c:80 [] entry_SYSCALL_64_after_hwframe+0x63/0xcd Fixes: 469aceddfa3e ("vlan: consolidate VLAN parsing code and limit max parsing depth") Reported-by: syzbot Signed-off-by: Eric Dumazet Cc: Toke Høiland-Jørgensen Cc: Willem de Bruijn Reviewed-by: Simon Horman --- drivers/net/tap.c | 4 ++-- include/linux/if_vlan.h | 17 +++++++++++++++++ net/bridge/br_forward.c | 2 +- net/core/dev.c | 2 +- net/packet/af_packet.c | 6 ++---- 5 files changed, 23 insertions(+), 8 deletions(-) diff --git a/drivers/net/tap.c b/drivers/net/tap.c index ce993cc75bf3106cd7fe71ab9d4188c6ac09af27..d30d730ed5a71b8cc31880acc0f82d4b0f65f739 100644 --- a/drivers/net/tap.c +++ b/drivers/net/tap.c @@ -742,7 +742,7 @@ static ssize_t tap_get_user(struct tap_queue *q, void *msg_control, /* Move network header to the right position for VLAN tagged packets */ if (eth_type_vlan(skb->protocol) && - __vlan_get_protocol(skb, skb->protocol, &depth) != 0) + vlan_get_protocol_and_depth(skb, skb->protocol, &depth) != 0) skb_set_network_header(skb, depth); /* copy skb_ubuf_info for callback when skb has no error */ @@ -1197,7 +1197,7 @@ static int tap_get_user_xdp(struct tap_queue *q, struct xdp_buff *xdp) /* Move network header to the right position for VLAN tagged packets */ if (eth_type_vlan(skb->protocol) && - __vlan_get_protocol(skb, skb->protocol, &depth) != 0) + vlan_get_protocol_and_depth(skb, skb->protocol, &depth) != 0) skb_set_network_header(skb, depth); rcu_read_lock(); diff --git a/include/linux/if_vlan.h b/include/linux/if_vlan.h index 0f40f379d75cb1e80aaff132842a8d1b968ad087..6ba71957851e22829ec9f18cd29bea2d92dfa583 100644 --- a/include/linux/if_vlan.h +++ b/include/linux/if_vlan.h @@ -637,6 +637,23 @@ static inline __be16 vlan_get_protocol(const struct sk_buff *skb) return __vlan_get_protocol(skb, skb->protocol, NULL); } +/* This version of __vlan_get_protocol() also pulls mac header in skb->head */ +static inline __be16 vlan_get_protocol_and_depth(struct sk_buff *skb, + __be16 type, int *depth) +{ + int maclen; + + type = __vlan_get_protocol(skb, type, &maclen); + + if (type) { + if (!pskb_may_pull(skb, maclen)) + type = 0; + else if (depth) + *depth = maclen; + } + return type; +} + /* A getter for the SKB protocol field which will handle VLAN tags consistently * whether VLAN acceleration is enabled or not. */ diff --git a/net/bridge/br_forward.c b/net/bridge/br_forward.c index 57744704ff692ae4dd573ec025cf29935785900e..84d6dd5e5b1a23a2fddad3e0573ebf7b1924204c 100644 --- a/net/bridge/br_forward.c +++ b/net/bridge/br_forward.c @@ -42,7 +42,7 @@ int br_dev_queue_push_xmit(struct net *net, struct sock *sk, struct sk_buff *skb eth_type_vlan(skb->protocol)) { int depth; - if (!__vlan_get_protocol(skb, skb->protocol, &depth)) + if (!vlan_get_protocol_and_depth(skb, skb->protocol, &depth)) goto drop; skb_set_network_header(skb, depth); diff --git a/net/core/dev.c b/net/core/dev.c index 735096d42c1d13999597a882370ca439e9389e24..b3c13e0419356b943e90b1f46dd7e035c6ec1a9c 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -3335,7 +3335,7 @@ __be16 skb_network_protocol(struct sk_buff *skb, int *depth) type = eth->h_proto; } - return __vlan_get_protocol(skb, type, depth); + return vlan_get_protocol_and_depth(skb, type, depth); } /* openvswitch calls this on rx path, so we need a different check. diff --git a/net/packet/af_packet.c b/net/packet/af_packet.c index 640d94e34635b51709d51be27635d23b3c184d0c..94c6a1ffa459aab491d92fb4fd96d58fb0e00094 100644 --- a/net/packet/af_packet.c +++ b/net/packet/af_packet.c @@ -1934,10 +1934,8 @@ static void packet_parse_headers(struct sk_buff *skb, struct socket *sock) /* Move network header to the right position for VLAN tagged packets */ if (likely(skb->dev->type == ARPHRD_ETHER) && eth_type_vlan(skb->protocol) && - __vlan_get_protocol(skb, skb->protocol, &depth) != 0) { - if (pskb_may_pull(skb, depth)) - skb_set_network_header(skb, depth); - } + vlan_get_protocol_and_depth(skb, skb->protocol, &depth) != 0) + skb_set_network_header(skb, depth); skb_probe_transport_header(skb); }