kernel/linux.git/include/net/gro.h, branch v6.6.93

net: gro: fix udp bad offset in socket lookup by adding {inner_}network_offset to napi_gro_cb

2024-05-17T10:02:07+00:00

[ Upstream commit 5ef31ea5d053a8f493a772ebad3f3ce82c35d845 ] Commits a602456 ("udp: Add GRO functions to UDP socket") and 57c67ff ("udp: additional GRO support") introduce incorrect usage of {ip,ipv6}_hdr in the complete phase of gro. The functions always return skb->network_header, which in the case of encapsulated packets at the gro complete phase, is always set to the innermost L3 of the packet. That means that calling {ip,ipv6}_hdr for skbs which completed the GRO receive phase (both in gro_list and *_gro_complete) when parsing an encapsulated packet's _outer_ L3/L4 may return an unexpected value. This incorrect usage leads to a bug in GRO's UDP socket lookup. udp{4,6}_lib_lookup_skb functions use ip_hdr/ipv6_hdr respectively. These *_hdr functions return network_header which will point to the innermost L3, resulting in the wrong offset being used in __udp{4,6}_lib_lookup with encapsulated packets. This patch adds network_offset and inner_network_offset to napi_gro_cb, and makes sure both are set correctly. To fix the issue, network_offsets union is used inside napi_gro_cb, in which both the outer and the inner network offsets are saved. Reproduction example: Endpoint configuration example (fou + local address bind) # ip fou add port 6666 ipproto 4 # ip link add name tun1 type ipip remote 2.2.2.1 local 2.2.2.2 encap fou encap-dport 5555 encap-sport 6666 mode ipip # ip link set tun1 up # ip a add 1.1.1.2/24 dev tun1 Netperf TCP_STREAM result on net-next before patch is applied: net-next main, GRO enabled: $ netperf -H 1.1.1.2 -t TCP_STREAM -l 5 Recv Send Send Socket Socket Message Elapsed Size Size Size Time Throughput bytes bytes bytes secs. 10^6bits/sec 131072 16384 16384 5.28 2.37 net-next main, GRO disabled: $ netperf -H 1.1.1.2 -t TCP_STREAM -l 5 Recv Send Send Socket Socket Message Elapsed Size Size Size Time Throughput bytes bytes bytes secs. 10^6bits/sec 131072 16384 16384 5.01 2745.06 patch applied, GRO enabled: $ netperf -H 1.1.1.2 -t TCP_STREAM -l 5 Recv Send Send Socket Socket Message Elapsed Size Size Size Time Throughput bytes bytes bytes secs. 10^6bits/sec 131072 16384 16384 5.01 2877.38 Fixes: a6024562ffd7 ("udp: Add GRO functions to UDP socket") Signed-off-by: Richard Gobert Reviewed-by: Eric Dumazet Reviewed-by: Willem de Bruijn Signed-off-by: Paolo Abeni Signed-off-by: Sasha Levin

net: gro: fix misuse of CB in udp socket lookup

2023-07-29T16:10:27+00:00

This patch fixes a misuse of IP{6}CB(skb) in GRO, while calling to `udp6_lib_lookup2` when handling udp tunnels. `udp6_lib_lookup2` fetch the device from CB. The fix changes it to fetch the device from `skb->dev`. l3mdev case requires special attention since it has a master and a slave device. Fixes: a6024562ffd7 ("udp: Add GRO functions to UDP socket") Reported-by: Gal Pressman Signed-off-by: Richard Gobert Reviewed-by: David Ahern Signed-off-by: David S. Miller

net: move gso declarations and functions to their own files

2023-06-10T07:11:41+00:00

Move declarations into include/net/gso.h and code into net/core/gso.c Signed-off-by: Eric Dumazet Cc: Stanislav Fomichev Reviewed-by: Simon Horman Reviewed-by: David Ahern Link: https://lore.kernel.org/r/20230608191738.3947077-1-edumazet@google.com Signed-off-by: Jakub Kicinski

gro: decrease size of CB

2023-06-06T09:12:20+00:00

The GRO control block (NAPI_GRO_CB) is currently at its maximum size. This commit reduces its size by putting two groups of fields that are used only at different times into a union. Specifically, the fields frag0 and frag0_len are the fields that make up the frag0 optimisation mechanism, which is used during the initial parsing of the SKB. The fields last and age are used after the initial parsing, while the SKB is stored in the GRO list, waiting for other packets to arrive. There was one location in dev_gro_receive that modified the frag0 fields after setting last and age. I changed this accordingly without altering the code behaviour. Signed-off-by: Richard Gobert Reviewed-by: Eric Dumazet Link: https://lore.kernel.org/r/20230601161407.GA9253@debian Signed-off-by: Paolo Abeni

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

2022-08-25T23:07:42+00:00

drivers/net/ethernet/mellanox/mlx5/core/en_fs.c 21234e3a84c7 ("net/mlx5e: Fix use after free in mlx5e_fs_init()") c7eafc5ed068 ("net/mlx5e: Convert ethtool_steering member of flow_steering struct to pointer") https://lore.kernel.org/all/20220825104410.67d4709c@canb.auug.org.au/ https://lore.kernel.org/all/20220823055533.334471-1-saeed@kernel.org/ Signed-off-by: Jakub Kicinski

net: gro: skb_gro_header helper function

2022-08-25T08:33:21+00:00

Introduce a simple helper function to replace a common pattern. When accessing the GRO header, we fetch the pointer from frag0, then test its validity and fetch it from the skb when necessary. This leads to the pattern skb_gro_header_fast -> skb_gro_header_hard -> skb_gro_header_slow recurring many times throughout GRO code. This patch replaces these patterns with a single inlined function call, improving code readability. Signed-off-by: Richard Gobert Reviewed-by: Eric Dumazet Link: https://lore.kernel.org/r/20220823071034.GA56142@debian Signed-off-by: Paolo Abeni

net: Fix a data-race around gro_normal_batch.

2022-08-24T12:46:58+00:00

While reading gro_normal_batch, it can be changed concurrently. Thus, we need to add READ_ONCE() to its reader. Fixes: 323ebb61e32b ("net: use listified RX for handling GRO_NORMAL skbs") Signed-off-by: Kuniyuki Iwashima Acked-by: Edward Cree Signed-off-by: David S. Miller

net: gro: Fix a 'directive in macro's argument list' sparse warning

2022-02-18T11:00:25+00:00

Following the cited commit, sparse started complaining about: ../include/net/gro.h:58:1: warning: directive in macro's argument list ../include/net/gro.h:59:1: warning: directive in macro's argument list Fix that by moving the defines out of the struct_group() macro. Fixes: de5a1f3ce4c8 ("net: gro: minor optimization for dev_gro_receive()") Reviewed-by: Maxim Mikityanskiy Signed-off-by: Gal Pressman Acked-by: Alexander Lobakin Acked-by: Paolo Abeni Signed-off-by: David S. Miller

net: gro: minor optimization for dev_gro_receive()

2022-02-05T15:13:52+00:00

While inspecting some perf report, I noticed that the compiler emits suboptimal code for the napi CB initialization, fetching and storing multiple times the memory for flags bitfield. This is with gcc 10.3.1, but I observed the same with older compiler versions. We can help the compiler to do a nicer work clearing several fields at once using an u32 alias. The generated code is quite smaller, with the same number of conditional. Before: objdump -t net/core/gro.o | grep " F .text" 0000000000000bb0 l F .text 0000000000000357 dev_gro_receive After: 0000000000000bb0 l F .text 000000000000033c dev_gro_receive v1 -> v2: - use struct_group (Alexander and Alex) RFC -> v1: - use __struct_group to delimit the zeroed area (Alexander) Signed-off-by: Paolo Abeni Signed-off-by: David S. Miller

net: fix recent csum changes

2021-12-07T00:26:46+00:00

Vladimir reported csum issues after my recent change in skb_postpull_rcsum() Issue here is the following: initial skb->csum is the csum of [part to be pulled][rest of packet] Old code: skb->csum = csum_sub(skb->csum, csum_partial(pull, pull_length, 0)); New code: skb->csum = ~csum_partial(pull, pull_length, ~skb->csum); This is broken if the csum of [pulled part] happens to be equal to skb->csum, because end result of skb->csum is 0 in new code, instead of being 0xffffffff David Laight suggested to use skb->csum = -csum_partial(pull, pull_length, -skb->csum); I based my patches on existing code present in include/net/seg6.h, update_csum_diff4() and update_csum_diff16() which might need a similar fix. I guess that my tests, mostly pulling 40 bytes of IPv6 header were not providing enough entropy to hit this bug. v2: added wsum_negate() to make sparse happy. Fixes: 29c3002644bd ("net: optimize skb_postpull_rcsum()") Fixes: 0bd28476f636 ("gro: optimize skb_gro_postpull_rcsum()") Signed-off-by: Eric Dumazet Reported-by: Vladimir Oltean Suggested-by: David Laight Cc: David Lebrun Tested-by: Vladimir Oltean Link: https://lore.kernel.org/r/20211204045356.3659278-1-eric.dumazet@gmail.com Signed-off-by: Jakub Kicinski