user/sven/linux.git/include/linux/virtio_net.h, branch v5.4.171

net: skip virtio_net_hdr_set_proto if protocol already set

2021-12-29T11:23:34Z

[ Upstream commit 1ed1d592113959f00cc552c3b9f47ca2d157768f ] virtio_net_hdr_set_proto infers skb->protocol from the virtio_net_hdr gso_type, to avoid packets getting dropped for lack of a proto type. Its protocol choice is a guess, especially in the case of UFO, where the single VIRTIO_NET_HDR_GSO_UDP label covers both UFOv4 and UFOv6. Skip this best effort if the field is already initialized. Whether explicitly from userspace, or implicitly based on an earlier call to dev_parse_header_protocol (which is more robust, but was introduced after this patch). Fixes: 9d2f67e43b73 ("net/packet: fix packet drop as of virtio gso") Signed-off-by: Willem de Bruijn Link: https://lore.kernel.org/r/20211220145027.2784293-1-willemdebruijn.kernel@gmail.com Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin

net: accept UFOv6 packages in virtio_net_hdr_to_skb

2021-12-29T11:23:34Z

[ Upstream commit 7e5cced9ca84df52d874aca6b632f930b3dc5bc6 ] Skb with skb->protocol 0 at the time of virtio_net_hdr_to_skb may have a protocol inferred from virtio_net_hdr with virtio_net_hdr_set_proto. Unlike TCP, UDP does not have separate types for IPv4 and IPv6. Type VIRTIO_NET_HDR_GSO_UDP is guessed to be IPv4/UDP. As of the below commit, UFOv6 packets are dropped due to not matching the protocol as obtained from dev_parse_header_protocol. Invert the test to take that L2 protocol field as starting point and pass both UFOv4 and UFOv6 for VIRTIO_NET_HDR_GSO_UDP. Fixes: 924a9bc362a5 ("net: check if protocol extracted by virtio_net_hdr_set_proto is correct") Link: https://lore.kernel.org/netdev/CABcq3pG9GRCYqFDBAJ48H1vpnnX=41u+MhQnayF1ztLH4WX0Fw@mail.gmail.com/ Reported-by: Andrew Melnichenko Signed-off-by: Willem de Bruijn Link: https://lore.kernel.org/r/20211220144901.2784030-1-willemdebruijn.kernel@gmail.com Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin

net: virtio_net_hdr_to_skb: count transport header in UFO

2021-11-26T09:47:19Z

[ Upstream commit cf9acc90c80ecbee00334aa85d92f4e74014bcff ] virtio_net_hdr_to_skb does not set the skb's gso_size and gso_type correctly for UFO packets received via virtio-net that are a little over the GSO size. This can lead to problems elsewhere in the networking stack, e.g. ovs_vport_send dropping over-sized packets if gso_size is not set. This is due to the comparison if (skb->len - p_off > gso_size) not properly accounting for the transport layer header. p_off includes the size of the transport layer header (thlen), so skb->len - p_off is the size of the TCP/UDP payload. gso_size is read from the virtio-net header. For UFO, fragmentation happens at the IP level so does not need to include the UDP header. Hence the calculation could be comparing a TCP/UDP payload length with an IP payload length, causing legitimate virtio-net packets to have lack gso_type/gso_size information. Example: a UDP packet with payload size 1473 has IP payload size 1481. If the guest used UFO, it is not fragmented and the virtio-net header's flags indicate that it is a GSO frame (VIRTIO_NET_HDR_GSO_UDP), with gso_size = 1480 for an MTU of 1500. skb->len will be 1515 and p_off will be 42, so skb->len - p_off = 1473. Hence the comparison fails, and shinfo->gso_size and gso_type are not set as they should be. Instead, add the UDP header length before comparing to gso_size when using UFO. In this way, it is the size of the IP payload that is compared to gso_size. Fixes: 6dd912f82680 ("net: check untrusted gso_size at kernel entry") Signed-off-by: Jonathan Davies Reviewed-by: Willem de Bruijn Signed-off-by: David S. Miller Signed-off-by: Sasha Levin

virtio_net: Do not pull payload in skb->head

2021-05-22T09:38:28Z

[ Upstream commit 0f6925b3e8da0dbbb52447ca8a8b42b371aac7db ] Xuan Zhuo reported that commit 3226b158e67c ("net: avoid 32 x truesize under-estimation for tiny skbs") brought a ~10% performance drop. The reason for the performance drop was that GRO was forced to chain sk_buff (using skb_shinfo(skb)->frag_list), which uses more memory but also cause packet consumers to go over a lot of overhead handling all the tiny skbs. It turns out that virtio_net page_to_skb() has a wrong strategy : It allocates skbs with GOOD_COPY_LEN (128) bytes in skb->head, then copies 128 bytes from the page, before feeding the packet to GRO stack. This was suboptimal before commit 3226b158e67c ("net: avoid 32 x truesize under-estimation for tiny skbs") because GRO was using 2 frags per MSS, meaning we were not packing MSS with 100% efficiency. Fix is to pull only the ethernet header in page_to_skb() Then, we change virtio_net_hdr_to_skb() to pull the missing headers, instead of assuming they were already pulled by callers. This fixes the performance regression, but could also allow virtio_net to accept packets with more than 128bytes of headers. Many thanks to Xuan Zhuo for his report, and his tests/help. Fixes: 3226b158e67c ("net: avoid 32 x truesize under-estimation for tiny skbs") Reported-by: Xuan Zhuo Link: https://www.spinics.net/lists/netdev/msg731397.html Co-Developed-by: Xuan Zhuo Signed-off-by: Xuan Zhuo Signed-off-by: Eric Dumazet Cc: "Michael S. Tsirkin" Cc: Jason Wang Cc: virtualization@lists.linux-foundation.org Acked-by: Jason Wang Signed-off-by: David S. Miller Signed-off-by: Sasha Levin

net: ensure mac header is set in virtio_net_hdr_to_skb()

2021-04-14T06:24:12Z

commit 61431a5907fc36d0738e9a547c7e1556349a03e9 upstream. Commit 924a9bc362a5 ("net: check if protocol extracted by virtio_net_hdr_set_proto is correct") added a call to dev_parse_header_protocol() but mac_header is not yet set. This means that eth_hdr() reads complete garbage, and syzbot complained about it [1] This patch resets mac_header earlier, to get more coverage about this change. Audit of virtio_net_hdr_to_skb() callers shows that this change should be safe. [1] BUG: KASAN: use-after-free in eth_header_parse_protocol+0xdc/0xe0 net/ethernet/eth.c:282 Read of size 2 at addr ffff888017a6200b by task syz-executor313/8409 CPU: 1 PID: 8409 Comm: syz-executor313 Not tainted 5.12.0-rc2-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:79 [inline] dump_stack+0x141/0x1d7 lib/dump_stack.c:120 print_address_description.constprop.0.cold+0x5b/0x2f8 mm/kasan/report.c:232 __kasan_report mm/kasan/report.c:399 [inline] kasan_report.cold+0x7c/0xd8 mm/kasan/report.c:416 eth_header_parse_protocol+0xdc/0xe0 net/ethernet/eth.c:282 dev_parse_header_protocol include/linux/netdevice.h:3177 [inline] virtio_net_hdr_to_skb.constprop.0+0x99d/0xcd0 include/linux/virtio_net.h:83 packet_snd net/packet/af_packet.c:2994 [inline] packet_sendmsg+0x2325/0x52b0 net/packet/af_packet.c:3031 sock_sendmsg_nosec net/socket.c:654 [inline] sock_sendmsg+0xcf/0x120 net/socket.c:674 sock_no_sendpage+0xf3/0x130 net/core/sock.c:2860 kernel_sendpage.part.0+0x1ab/0x350 net/socket.c:3631 kernel_sendpage net/socket.c:3628 [inline] sock_sendpage+0xe5/0x140 net/socket.c:947 pipe_to_sendpage+0x2ad/0x380 fs/splice.c:364 splice_from_pipe_feed fs/splice.c:418 [inline] __splice_from_pipe+0x43e/0x8a0 fs/splice.c:562 splice_from_pipe fs/splice.c:597 [inline] generic_splice_sendpage+0xd4/0x140 fs/splice.c:746 do_splice_from fs/splice.c:767 [inline] do_splice+0xb7e/0x1940 fs/splice.c:1079 __do_splice+0x134/0x250 fs/splice.c:1144 __do_sys_splice fs/splice.c:1350 [inline] __se_sys_splice fs/splice.c:1332 [inline] __x64_sys_splice+0x198/0x250 fs/splice.c:1332 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 Fixes: 924a9bc362a5 ("net: check if protocol extracted by virtio_net_hdr_set_proto is correct") Signed-off-by: Eric Dumazet Cc: Balazs Nemeth Cc: Willem de Bruijn Reported-by: syzbot Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

net: check if protocol extracted by virtio_net_hdr_set_proto is correct

2021-03-17T16:03:30Z

commit 924a9bc362a5223cd448ca08c3dde21235adc310 upstream. For gso packets, virtio_net_hdr_set_proto sets the protocol (if it isn't set) based on the type in the virtio net hdr, but the skb could contain anything since it could come from packet_snd through a raw socket. If there is a mismatch between what virtio_net_hdr_set_proto sets and the actual protocol, then the skb could be handled incorrectly later on. An example where this poses an issue is with the subsequent call to skb_flow_dissect_flow_keys_basic which relies on skb->protocol being set correctly. A specially crafted packet could fool skb_flow_dissect_flow_keys_basic preventing EINVAL to be returned. Avoid blindly trusting the information provided by the virtio net header by checking that the protocol in the packet actually matches the protocol set by virtio_net_hdr_set_proto. Note that since the protocol is only checked if skb->dev implements header_ops->parse_protocol, packets from devices without the implementation are not checked at this stage. Fixes: 9274124f023b ("net: stricter validation of untrusted gso packets") Signed-off-by: Balazs Nemeth Acked-by: Willem de Bruijn Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

net: be more gentle about silly gso requests coming from user

2020-06-10T18:24:55Z

[ Upstream commit 7c6d2ecbda83150b2036a2b36b21381ad4667762 ] Recent change in virtio_net_hdr_to_skb() broke some packetdrill tests. When --mss=XXX option is set, packetdrill always provide gso_type & gso_size for its inbound packets, regardless of packet size. if (packet->tcp && packet->mss) { if (packet->ipv4) gso.gso_type = VIRTIO_NET_HDR_GSO_TCPV4; else gso.gso_type = VIRTIO_NET_HDR_GSO_TCPV6; gso.gso_size = packet->mss; } Since many other programs could do the same, relax virtio_net_hdr_to_skb() to no longer return an error, but instead ignore gso settings. This keeps Willem intent to make sure no malicious packet could reach gso stack. Note that TCP stack has a special logic in tcp_set_skb_tso_segs() to clear gso_size for small packets. Fixes: 6dd912f82680 ("net: check untrusted gso_size at kernel entry") Signed-off-by: Eric Dumazet Cc: Willem de Bruijn Acked-by: Willem de Bruijn Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

net: check untrusted gso_size at kernel entry

2020-06-10T18:24:55Z

[ Upstream commit 6dd912f82680761d8fb6b1bb274a69d4c7010988 ] Syzkaller again found a path to a kernel crash through bad gso input: a packet with gso size exceeding len. These packets are dropped in tcp_gso_segment and udp[46]_ufo_fragment. But they may affect gso size calculations earlier in the path. Now that we have thlen as of commit 9274124f023b ("net: stricter validation of untrusted gso packets"), check gso_size at entry too. Fixes: bfd5f4a3d605 ("packet: Add GSO/csum offload support.") Reported-by: syzbot Signed-off-by: Willem de Bruijn Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

net: stricter validation of untrusted gso packets

2020-05-14T05:58:21Z

[ Upstream commit 9274124f023b5c56dc4326637d4f787968b03607 ] Syzkaller again found a path to a kernel crash through bad gso input: a packet with transport header extending beyond skb_headlen(skb). Tighten validation at kernel entry: - Verify that the transport header lies within the linear section. To avoid pulling linux/tcp.h, verify just sizeof tcphdr. tcp_gso_segment will call pskb_may_pull (th->doff * 4) before use. - Match the gso_type against the ip_proto found by the flow dissector. Fixes: bfd5f4a3d605 ("packet: Add GSO/csum offload support.") Reported-by: syzbot Signed-off-by: Willem de Bruijn Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net

2019-02-24T20:06:19Z

Three conflicts, one of which, for marvell10g.c is non-trivial and requires some follow-up from Heiner or someone else. The issue is that Heiner converted the marvell10g driver over to use the generic c45 code as much as possible. However, in 'net' a bug fix appeared which makes sure that a new local mask (MDIO_AN_10GBT_CTRL_ADV_NBT_MASK) with value 0x01e0 is cleared. Signed-off-by: David S. Miller