From patchwork Fri Mar 11 09:14:18 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Lorenzo Bianconi X-Patchwork-Id: 12777696 X-Patchwork-Delegate: bpf@iogearbox.net 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 AEF46C433F5 for ; Fri, 11 Mar 2022 09:15:08 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1345408AbiCKJQJ (ORCPT ); Fri, 11 Mar 2022 04:16:09 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:60600 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235073AbiCKJQI (ORCPT ); Fri, 11 Mar 2022 04:16:08 -0500 Received: from ams.source.kernel.org (ams.source.kernel.org [145.40.68.75]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id D9D4F1BB739; Fri, 11 Mar 2022 01:15:05 -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 59A5CB8299A; Fri, 11 Mar 2022 09:15:04 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 6B4C2C340E9; Fri, 11 Mar 2022 09:15:00 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1646990103; bh=rXL77Q12KqMeZVo0cFoB+g0xbu14At7FWgr78IMxYmg=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=BJTBIhalogwxLVq6h70/YhceHEGgNBRIEz5CU4p/+YsqAe9zCNcuVUAdU5ZNYy2+4 4EATkO4l0FZg97ev1bj/yju5jCTl4nlkEC23YBJ/mhieyeSp7xMDCyzT8P6gr4Uq5l 9XLzg5OFzQjtSRgiFc2I3Go8E0JLSQCy/z/N6JstMw5aASKU6gsL3uu0TXwcn3IFsy jLSt6wa+G3MB4sgjZEZtDgd6u+EfKhqEgwGQv1XWs5FFyfpg98c3nXHC0PLuXV2p3q pE0iTdWWPAkH6mG2G37lk3/MxR5/K92gApiHLSZU2Y0I1F2xuLXpq715fBxNiM6rZ4 iUClQOorEEgiA== From: Lorenzo Bianconi To: bpf@vger.kernel.org, netdev@vger.kernel.org Cc: davem@davemloft.net, kuba@kernel.org, ast@kernel.org, daniel@iogearbox.net, brouer@redhat.com, toke@redhat.com, pabeni@redhat.com, echaudro@redhat.com, lorenzo.bianconi@redhat.com, toshiaki.makita1@gmail.com, andrii@kernel.org Subject: [PATCH v5 bpf-next 1/3] net: veth: account total xdp_frame len running ndo_xdp_xmit Date: Fri, 11 Mar 2022 10:14:18 +0100 Message-Id: <54f9fd3bb65d190daf2c0bbae2f852ff16cfbaa0.1646989407.git.lorenzo@kernel.org> X-Mailer: git-send-email 2.35.1 In-Reply-To: References: MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org X-Patchwork-Delegate: bpf@iogearbox.net Even if this is a theoretical issue since it is not possible to perform XDP_REDIRECT on a non-linear xdp_frame, veth driver does not account paged area in ndo_xdp_xmit function pointer. Introduce xdp_get_frame_len utility routine to get the xdp_frame full length and account total frame size running XDP_REDIRECT of a non-linear xdp frame into a veth device. Acked-by: Toke Hoiland-Jorgensen Signed-off-by: Lorenzo Bianconi Acked-by: John Fastabend --- drivers/net/veth.c | 4 ++-- include/net/xdp.h | 14 ++++++++++++++ 2 files changed, 16 insertions(+), 2 deletions(-) diff --git a/drivers/net/veth.c b/drivers/net/veth.c index 58b20ea171dd..b77ce3fdcfe8 100644 --- a/drivers/net/veth.c +++ b/drivers/net/veth.c @@ -494,7 +494,7 @@ static int veth_xdp_xmit(struct net_device *dev, int n, struct xdp_frame *frame = frames[i]; void *ptr = veth_xdp_to_ptr(frame); - if (unlikely(frame->len > max_len || + if (unlikely(xdp_get_frame_len(frame) > max_len || __ptr_ring_produce(&rq->xdp_ring, ptr))) break; nxmit++; @@ -855,7 +855,7 @@ static int veth_xdp_rcv(struct veth_rq *rq, int budget, /* ndo_xdp_xmit */ struct xdp_frame *frame = veth_ptr_to_xdp(ptr); - stats->xdp_bytes += frame->len; + stats->xdp_bytes += xdp_get_frame_len(frame); frame = veth_xdp_rcv_one(rq, frame, bq, stats); if (frame) { /* XDP_PASS */ diff --git a/include/net/xdp.h b/include/net/xdp.h index b7721c3e4d1f..04c852c7a77f 100644 --- a/include/net/xdp.h +++ b/include/net/xdp.h @@ -343,6 +343,20 @@ static inline void xdp_release_frame(struct xdp_frame *xdpf) __xdp_release_frame(xdpf->data, mem); } +static __always_inline unsigned int xdp_get_frame_len(struct xdp_frame *xdpf) +{ + struct skb_shared_info *sinfo; + unsigned int len = xdpf->len; + + if (likely(!xdp_frame_has_frags(xdpf))) + goto out; + + sinfo = xdp_get_shared_info_from_frame(xdpf); + len += sinfo->xdp_frags_size; +out: + return len; +} + int __xdp_rxq_info_reg(struct xdp_rxq_info *xdp_rxq, struct net_device *dev, u32 queue_index, unsigned int napi_id, u32 frag_size); From patchwork Fri Mar 11 09:14:19 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Lorenzo Bianconi X-Patchwork-Id: 12777697 X-Patchwork-Delegate: bpf@iogearbox.net 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 E130CC4332F for ; Fri, 11 Mar 2022 09:15:16 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1346172AbiCKJQQ (ORCPT ); Fri, 11 Mar 2022 04:16:16 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:60812 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1345646AbiCKJQL (ORCPT ); Fri, 11 Mar 2022 04:16:11 -0500 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id CB4941BB73A; Fri, 11 Mar 2022 01:15:07 -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 dfw.source.kernel.org (Postfix) with ESMTPS id 5A16C61F2A; Fri, 11 Mar 2022 09:15:07 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 1BA37C340F3; Fri, 11 Mar 2022 09:15:03 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1646990106; bh=HCCSiwwusuPFDujvRRxiAqoFYDqBp1+SqwDe+Bwssw8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=P3M+p0MJZXZQK0gbKYwLsoz0v4XUrCAlkeHhXe6nno3ZBCPDKJV+ZykWTF2tmDI5J zn8oSk7Fdl1+q1qE9IM1IlQDJIQ7kWYl+bSF1xZG4azhutachgP9kZGRj8gLDV2lkT za1kATzZKiq2dAO1X0ZitxqjuTvavqneves+5PzcdwTi4D+girEjuA8rnYx/gXpbhF 7iMBHB77Gl++iqscUP2pzjN5O8wu6YKm6ZMiT+uuoowsPSb2s0fKiJVtYCzcVETV3I A6iqA5Hk/J53Dc2q9MM2BvYSZwfvraiIf/WjLhEPADNzQfg/zynwiUip+6tsQ3xOuF +dDqPWQTK827g== From: Lorenzo Bianconi To: bpf@vger.kernel.org, netdev@vger.kernel.org Cc: davem@davemloft.net, kuba@kernel.org, ast@kernel.org, daniel@iogearbox.net, brouer@redhat.com, toke@redhat.com, pabeni@redhat.com, echaudro@redhat.com, lorenzo.bianconi@redhat.com, toshiaki.makita1@gmail.com, andrii@kernel.org Subject: [PATCH v5 bpf-next 2/3] veth: rework veth_xdp_rcv_skb in order to accept non-linear skb Date: Fri, 11 Mar 2022 10:14:19 +0100 Message-Id: <8d228b106bc1903571afd1d77e797bffe9a5ea7c.1646989407.git.lorenzo@kernel.org> X-Mailer: git-send-email 2.35.1 In-Reply-To: References: MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org X-Patchwork-Delegate: bpf@iogearbox.net Introduce veth_convert_skb_to_xdp_buff routine in order to convert a non-linear skb into a xdp buffer. If the received skb is cloned or shared, veth_convert_skb_to_xdp_buff will copy it in a new skb composed by order-0 pages for the linear and the fragmented area. Moreover veth_convert_skb_to_xdp_buff guarantees we have enough headroom for xdp. This is a preliminary patch to allow attaching xdp programs with frags support on veth devices. Signed-off-by: Lorenzo Bianconi Acked-by: Toke Høiland-Jørgensen Acked-by: John Fastabend --- drivers/net/veth.c | 177 +++++++++++++++++++++++++++++++-------------- net/core/xdp.c | 1 + 2 files changed, 122 insertions(+), 56 deletions(-) diff --git a/drivers/net/veth.c b/drivers/net/veth.c index b77ce3fdcfe8..bfae15ec902b 100644 --- a/drivers/net/veth.c +++ b/drivers/net/veth.c @@ -433,21 +433,6 @@ static void veth_set_multicast_list(struct net_device *dev) { } -static struct sk_buff *veth_build_skb(void *head, int headroom, int len, - int buflen) -{ - struct sk_buff *skb; - - skb = build_skb(head, buflen); - if (!skb) - return NULL; - - skb_reserve(skb, headroom); - skb_put(skb, len); - - return skb; -} - static int veth_select_rxq(struct net_device *dev) { return smp_processor_id() % dev->real_num_rx_queues; @@ -695,72 +680,143 @@ static void veth_xdp_rcv_bulk_skb(struct veth_rq *rq, void **frames, } } -static struct sk_buff *veth_xdp_rcv_skb(struct veth_rq *rq, - struct sk_buff *skb, - struct veth_xdp_tx_bq *bq, - struct veth_stats *stats) +static void veth_xdp_get(struct xdp_buff *xdp) { - u32 pktlen, headroom, act, metalen, frame_sz; - void *orig_data, *orig_data_end; - struct bpf_prog *xdp_prog; - int mac_len, delta, off; - struct xdp_buff xdp; + struct skb_shared_info *sinfo = xdp_get_shared_info_from_buff(xdp); + int i; - skb_prepare_for_gro(skb); + get_page(virt_to_page(xdp->data)); + if (likely(!xdp_buff_has_frags(xdp))) + return; - rcu_read_lock(); - xdp_prog = rcu_dereference(rq->xdp_prog); - if (unlikely(!xdp_prog)) { - rcu_read_unlock(); - goto out; - } + for (i = 0; i < sinfo->nr_frags; i++) + __skb_frag_ref(&sinfo->frags[i]); +} - mac_len = skb->data - skb_mac_header(skb); - pktlen = skb->len + mac_len; - headroom = skb_headroom(skb) - mac_len; +static int veth_convert_skb_to_xdp_buff(struct veth_rq *rq, + struct xdp_buff *xdp, + struct sk_buff **pskb) +{ + struct sk_buff *skb = *pskb; + u32 frame_sz; if (skb_shared(skb) || skb_head_is_locked(skb) || - skb_is_nonlinear(skb) || headroom < XDP_PACKET_HEADROOM) { + skb_shinfo(skb)->nr_frags) { + u32 size, len, max_head_size, off; struct sk_buff *nskb; - int size, head_off; - void *head, *start; struct page *page; + int i, head_off; - size = SKB_DATA_ALIGN(VETH_XDP_HEADROOM + pktlen) + - SKB_DATA_ALIGN(sizeof(struct skb_shared_info)); - if (size > PAGE_SIZE) + /* We need a private copy of the skb and data buffers since + * the ebpf program can modify it. We segment the original skb + * into order-0 pages without linearize it. + * + * Make sure we have enough space for linear and paged area + */ + max_head_size = SKB_WITH_OVERHEAD(PAGE_SIZE - + VETH_XDP_HEADROOM); + if (skb->len > PAGE_SIZE * MAX_SKB_FRAGS + max_head_size) goto drop; + /* Allocate skb head */ page = alloc_page(GFP_ATOMIC | __GFP_NOWARN); if (!page) goto drop; - head = page_address(page); - start = head + VETH_XDP_HEADROOM; - if (skb_copy_bits(skb, -mac_len, start, pktlen)) { - page_frag_free(head); + nskb = build_skb(page_address(page), PAGE_SIZE); + if (!nskb) { + put_page(page); goto drop; } - nskb = veth_build_skb(head, VETH_XDP_HEADROOM + mac_len, - skb->len, PAGE_SIZE); - if (!nskb) { - page_frag_free(head); + skb_reserve(nskb, VETH_XDP_HEADROOM); + size = min_t(u32, skb->len, max_head_size); + if (skb_copy_bits(skb, 0, nskb->data, size)) { + consume_skb(nskb); goto drop; } + skb_put(nskb, size); skb_copy_header(nskb, skb); head_off = skb_headroom(nskb) - skb_headroom(skb); skb_headers_offset_update(nskb, head_off); + + /* Allocate paged area of new skb */ + off = size; + len = skb->len - off; + + for (i = 0; i < MAX_SKB_FRAGS && off < skb->len; i++) { + page = alloc_page(GFP_ATOMIC | __GFP_NOWARN); + if (!page) { + consume_skb(nskb); + goto drop; + } + + size = min_t(u32, len, PAGE_SIZE); + skb_add_rx_frag(nskb, i, page, 0, size, PAGE_SIZE); + if (skb_copy_bits(skb, off, page_address(page), + size)) { + consume_skb(nskb); + goto drop; + } + + len -= size; + off += size; + } + consume_skb(skb); skb = nskb; + } else if (skb_headroom(skb) < XDP_PACKET_HEADROOM && + pskb_expand_head(skb, VETH_XDP_HEADROOM, 0, GFP_ATOMIC)) { + goto drop; } /* SKB "head" area always have tailroom for skb_shared_info */ frame_sz = skb_end_pointer(skb) - skb->head; frame_sz += SKB_DATA_ALIGN(sizeof(struct skb_shared_info)); - xdp_init_buff(&xdp, frame_sz, &rq->xdp_rxq); - xdp_prepare_buff(&xdp, skb->head, skb->mac_header, pktlen, true); + xdp_init_buff(xdp, frame_sz, &rq->xdp_rxq); + xdp_prepare_buff(xdp, skb->head, skb_headroom(skb), + skb_headlen(skb), true); + + if (skb_is_nonlinear(skb)) { + skb_shinfo(skb)->xdp_frags_size = skb->data_len; + xdp_buff_set_frags_flag(xdp); + } else { + xdp_buff_clear_frags_flag(xdp); + } + *pskb = skb; + + return 0; +drop: + consume_skb(skb); + *pskb = NULL; + + return -ENOMEM; +} + +static struct sk_buff *veth_xdp_rcv_skb(struct veth_rq *rq, + struct sk_buff *skb, + struct veth_xdp_tx_bq *bq, + struct veth_stats *stats) +{ + void *orig_data, *orig_data_end; + struct bpf_prog *xdp_prog; + struct xdp_buff xdp; + u32 act, metalen; + int off; + + skb_prepare_for_gro(skb); + + rcu_read_lock(); + xdp_prog = rcu_dereference(rq->xdp_prog); + if (unlikely(!xdp_prog)) { + rcu_read_unlock(); + goto out; + } + + __skb_push(skb, skb->data - skb_mac_header(skb)); + if (veth_convert_skb_to_xdp_buff(rq, &xdp, &skb)) + goto drop; orig_data = xdp.data; orig_data_end = xdp.data_end; @@ -771,7 +827,7 @@ static struct sk_buff *veth_xdp_rcv_skb(struct veth_rq *rq, case XDP_PASS: break; case XDP_TX: - get_page(virt_to_page(xdp.data)); + veth_xdp_get(&xdp); consume_skb(skb); xdp.rxq->mem = rq->xdp_mem; if (unlikely(veth_xdp_tx(rq, &xdp, bq) < 0)) { @@ -783,7 +839,7 @@ static struct sk_buff *veth_xdp_rcv_skb(struct veth_rq *rq, rcu_read_unlock(); goto xdp_xmit; case XDP_REDIRECT: - get_page(virt_to_page(xdp.data)); + veth_xdp_get(&xdp); consume_skb(skb); xdp.rxq->mem = rq->xdp_mem; if (xdp_do_redirect(rq->dev, &xdp, xdp_prog)) { @@ -806,18 +862,27 @@ static struct sk_buff *veth_xdp_rcv_skb(struct veth_rq *rq, rcu_read_unlock(); /* check if bpf_xdp_adjust_head was used */ - delta = orig_data - xdp.data; - off = mac_len + delta; + off = orig_data - xdp.data; if (off > 0) __skb_push(skb, off); else if (off < 0) __skb_pull(skb, -off); - skb->mac_header -= delta; + + skb_reset_mac_header(skb); /* check if bpf_xdp_adjust_tail was used */ off = xdp.data_end - orig_data_end; if (off != 0) __skb_put(skb, off); /* positive on grow, negative on shrink */ + + /* XDP frag metadata (e.g. nr_frags) are updated in eBPF helpers + * (e.g. bpf_xdp_adjust_tail), we need to update data_len here. + */ + if (xdp_buff_has_frags(&xdp)) + skb->data_len = skb_shinfo(skb)->xdp_frags_size; + else + skb->data_len = 0; + skb->protocol = eth_type_trans(skb, rq->dev); metalen = xdp.data - xdp.data_meta; @@ -833,7 +898,7 @@ static struct sk_buff *veth_xdp_rcv_skb(struct veth_rq *rq, return NULL; err_xdp: rcu_read_unlock(); - page_frag_free(xdp.data); + xdp_return_buff(&xdp); xdp_xmit: return NULL; } diff --git a/net/core/xdp.c b/net/core/xdp.c index 361df312ee7f..b5f2d428d856 100644 --- a/net/core/xdp.c +++ b/net/core/xdp.c @@ -528,6 +528,7 @@ void xdp_return_buff(struct xdp_buff *xdp) out: __xdp_return(xdp->data, &xdp->rxq->mem, true, xdp); } +EXPORT_SYMBOL_GPL(xdp_return_buff); /* Only called for MEM_TYPE_PAGE_POOL see xdp.h */ void __xdp_release_frame(void *data, struct xdp_mem_info *mem) From patchwork Fri Mar 11 09:14:20 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Lorenzo Bianconi X-Patchwork-Id: 12777698 X-Patchwork-Delegate: bpf@iogearbox.net 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 7FEE7C433FE for ; Fri, 11 Mar 2022 09:15:18 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1345942AbiCKJQS (ORCPT ); Fri, 11 Mar 2022 04:16:18 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:32798 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235073AbiCKJQP (ORCPT ); Fri, 11 Mar 2022 04:16:15 -0500 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id A87291BBF45; Fri, 11 Mar 2022 01:15:11 -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 dfw.source.kernel.org (Postfix) with ESMTPS id 45A9061F2B; Fri, 11 Mar 2022 09:15:11 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 04B9BC340E9; Fri, 11 Mar 2022 09:15:07 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1646990110; bh=c61+9/J2HkxPYOFusMQumMxePvjg9hKFovxmJgey1to=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=iop+DWtIjJkMlUCEylX+HGdzTT0emHfBDcXbJbA2CRYwU5+uhcRCnZLYeO6/uvT1n flELcwfb+4plMyLSVah3m7+ZeOAokTJ3Ea6SWO2IhPmRKcSYsRcNMiJoJEH6i8kQ1s 1ViRKtI9MRopgk/6pnYVQEYe6QGAnHSZ4NJ0O9i+sK/yS+eQZLx946qDg8nqVnvx/p NzxpCpke+Vp/mj89iQ+dM3An8jGu2SDYdpQ3Oq/ALZmV95kko71w7CAi4FiS9SCaCv 2jejqYGMj6DEH2qVt2yMBaBIq7n8CO3E/5458yzWU2Cn6q1MxRbKk1rkqz51FrTFg1 prfEadv7QFVRQ== From: Lorenzo Bianconi To: bpf@vger.kernel.org, netdev@vger.kernel.org Cc: davem@davemloft.net, kuba@kernel.org, ast@kernel.org, daniel@iogearbox.net, brouer@redhat.com, toke@redhat.com, pabeni@redhat.com, echaudro@redhat.com, lorenzo.bianconi@redhat.com, toshiaki.makita1@gmail.com, andrii@kernel.org Subject: [PATCH v5 bpf-next 3/3] veth: allow jumbo frames in xdp mode Date: Fri, 11 Mar 2022 10:14:20 +0100 Message-Id: X-Mailer: git-send-email 2.35.1 In-Reply-To: References: MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org X-Patchwork-Delegate: bpf@iogearbox.net Allow increasing the MTU over page boundaries on veth devices if the attached xdp program declares to support xdp fragments. Signed-off-by: Lorenzo Bianconi Acked-by: Toke Høiland-Jørgensen Acked-by: John Fastabend --- drivers/net/veth.c | 11 ++++++++--- 1 file changed, 8 insertions(+), 3 deletions(-) diff --git a/drivers/net/veth.c b/drivers/net/veth.c index bfae15ec902b..1b5714926d81 100644 --- a/drivers/net/veth.c +++ b/drivers/net/veth.c @@ -1528,9 +1528,14 @@ static int veth_xdp_set(struct net_device *dev, struct bpf_prog *prog, goto err; } - max_mtu = PAGE_SIZE - VETH_XDP_HEADROOM - - peer->hard_header_len - - SKB_DATA_ALIGN(sizeof(struct skb_shared_info)); + max_mtu = SKB_WITH_OVERHEAD(PAGE_SIZE - VETH_XDP_HEADROOM) - + peer->hard_header_len; + /* Allow increasing the max_mtu if the program supports + * XDP fragments. + */ + if (prog->aux->xdp_has_frags) + max_mtu += PAGE_SIZE * MAX_SKB_FRAGS; + if (peer->mtu > max_mtu) { NL_SET_ERR_MSG_MOD(extack, "Peer MTU is too large to set XDP"); err = -ERANGE;