From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 454074B44CC; Thu, 17 Sep 2026 15:38:07 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789659493; cv=none; b=WW/hc3HoSh0w2sun8Bigh8Y2+vjO008oHkaRj7vjyxykbAxTNfv9StItZWtuv/jZ4G3kgvZz5KEGJ/+Qg60RqHFB2dmUx9kDuLrB5ZzyPaAHZ5W7UTrgeJt1r1rVlPnBckGbzteRWU3O0fmzdy7TBrsTWzI3YDxnGPpMFbrNgSM= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789659493; c=relaxed/simple; bh=U591tsCwOio8HFGEHszi7g2CVRO0aQwiWSy1aywOK8k=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=ttl53eIpQLmsCZBH9lXN/f5JeLb3t/hshXtdLq+qYNEvaytphQ52J8+ZH7xVfbDroOKcas2TE0HJ4+Y/CyJLTOCBfiZ1gp4zLtFzu5YmJPlA64osYXZN1G77Bx20IukSV3wc569c90mNX6XhwYQ0duAOqVU9f1mWzmqELQOlmJc= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=MpQSKcul; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="MpQSKcul" Received: by smtp.kernel.org (Postfix) with ESMTPSA id BBFA41F00898; Thu, 17 Sep 2026 15:38:06 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1789659487; bh=XlJIlo/jlK91tBe2exG2p8Uu73ks/OIwVYpzcFx6lq4=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=MpQSKculSmLF2h3eHmWQTiM2jUTSDprBoWM7ll+bAJEGX4AdiK6ssP7N5ux9blEeQ UU24WiKw6tY5yU8RjYoI9dZrySq5MQkbdfmDLVc+MAv2xg6NYWf0NojaCHq0qVLmvb 5u6uXAhTj/OrRNLWuKHeBU0nCaYCDfhBE1VQIJo4= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Eric Dumazet , Hangbin Liu , Jay Vosburgh , Nikolay Aleksandrov , Jakub Kicinski , Sasha Levin Subject: [PATCH 7.2 273/733] bonding: use skb_cow_head() in bond_do_alb_xmit() and rlb_arp_xmit() Date: Thu, 17 Sep 2026 16:09:41 +0100 Message-ID: <20260917151358.154389287@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260917151350.597953846@linuxfoundation.org> References: <20260917151350.597953846@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 7.2-stable review patch. If anyone has any objections, please let me know. ------------------ From: Eric Dumazet [ Upstream commit 1746ef2e2df2ad71c66eca56364d56bde284523b ] In bond_do_alb_xmit() and rlb_arp_xmit(), make sure to unclone skb head via skb_cow_head() before modifying the source MAC address (Ethernet header and ARP payload) to avoid silent corruption if the skb is shared or cloned. Avoid caching the header pointers across skb_cow_head(). In rlb_arp_xmit(), only modify arp->mac_src if it differs from tx_slave->dev->dev_addr to avoid an unnecessary copy and head reallocation. Also, we should not assume mac header is set in output path. Use skb_eth_hdr() instead of eth_hdr() to fix the issue, and remove now redundant skb_reset_mac_header() calls. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Eric Dumazet Reviewed-by: Hangbin Liu Cc: Jay Vosburgh Reviewed-by: Nikolay Aleksandrov Link: https://patch.msgid.link/20260903143940.1180513-1-edumazet@google.com Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin --- drivers/net/bonding/bond_alb.c | 19 ++++++++++++------- 1 file changed, 12 insertions(+), 7 deletions(-) diff --git a/drivers/net/bonding/bond_alb.c b/drivers/net/bonding/bond_alb.c index 654f051d00239..43ac8e28e4182 100644 --- a/drivers/net/bonding/bond_alb.c +++ b/drivers/net/bonding/bond_alb.c @@ -678,9 +678,15 @@ static struct slave *rlb_arp_xmit(struct sk_buff *skb, struct bonding *bond) if (arp->op_code == htons(ARPOP_REPLY)) { /* the arp must be sent on the selected rx channel */ tx_slave = rlb_choose_channel(skb, bond, arp); - if (tx_slave) + if (tx_slave && + !ether_addr_equal_64bits(arp->mac_src, + tx_slave->dev->dev_addr)) { + if (unlikely(skb_cow_head(skb, 0))) + return NULL; + arp = (struct arp_pkt *)skb_network_header(skb); bond_hw_addr_copy(arp->mac_src, tx_slave->dev->dev_addr, tx_slave->dev->addr_len); + } netdev_dbg(bond->dev, "(slave %s): Server sent ARP Reply packet\n", tx_slave ? tx_slave->dev->name : "NULL"); } else if (arp->op_code == htons(ARPOP_REQUEST)) { @@ -1340,7 +1346,6 @@ static netdev_tx_t bond_do_alb_xmit(struct sk_buff *skb, struct bonding *bond, struct slave *tx_slave) { struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond)); - struct ethhdr *eth_data = eth_hdr(skb); if (!tx_slave) { /* unbalanced or unassigned, send through primary */ @@ -1351,7 +1356,9 @@ static netdev_tx_t bond_do_alb_xmit(struct sk_buff *skb, struct bonding *bond, if (tx_slave && bond_slave_can_tx(tx_slave)) { if (tx_slave != rcu_access_pointer(bond->curr_active_slave)) { - ether_addr_copy(eth_data->h_source, + if (unlikely(skb_cow_head(skb, 0))) + return bond_tx_drop(bond->dev, skb); + ether_addr_copy(skb_eth_hdr(skb)->h_source, tx_slave->dev->dev_addr); } @@ -1375,8 +1382,7 @@ struct slave *bond_xmit_tlb_slave_get(struct bonding *bond, struct ethhdr *eth_data; u32 hash_index; - skb_reset_mac_header(skb); - eth_data = eth_hdr(skb); + eth_data = skb_eth_hdr(skb); /* Do not TX balance any multicast or broadcast */ if (!is_multicast_ether_addr(eth_data->h_dest)) { @@ -1428,8 +1434,7 @@ struct slave *bond_xmit_alb_slave_get(struct bonding *bond, u32 hash_index = 0; int hash_size = 0; - skb_reset_mac_header(skb); - eth_data = eth_hdr(skb); + eth_data = skb_eth_hdr(skb); switch (ntohs(skb->protocol)) { case ETH_P_IP: { -- 2.53.0