linux-stable.git/drivers/net/veth.c, branch v6.3 Linux kernel stable tree veth: take into account peer device for NETDEV_XDP_ACT_NDO_XMIT xdp_features flag 2023-04-18T18:10:58+00:00 Lorenzo Bianconi lorenzo@kernel.org 2023-04-17T21:53:22+00:00 8267fc71abb2dc47338570e56dd3473a58313fce For veth pairs, NETDEV_XDP_ACT_NDO_XMIT is supported by the current device if the peer one is running a XDP program or if it has GRO enabled. Fix the xdp_features flags reporting considering peer device and not current one for NETDEV_XDP_ACT_NDO_XMIT. Fixes: fccca038f300 ("veth: take into account device reconfiguration for xdp_features flag") Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org> Link: https://lore.kernel.org/r/4f1ca6f6f6b42ae125bfdb5c7782217c83968b2e.1681767806.git.lorenzo@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> 
For veth pairs, NETDEV_XDP_ACT_NDO_XMIT is supported by the current
device if the peer one is running a XDP program or if it has GRO enabled.
Fix the xdp_features flags reporting considering peer device and not
current one for NETDEV_XDP_ACT_NDO_XMIT.

Fixes: fccca038f300 ("veth: take into account device reconfiguration for xdp_features flag")
Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
Link: https://lore.kernel.org/r/4f1ca6f6f6b42ae125bfdb5c7782217c83968b2e.1681767806.git.lorenzo@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
veth: bpf_xdp_metadata_rx_hash add xdp rss hash type 2023-04-13T18:15:10+00:00 Jesper Dangaard Brouer brouer@redhat.com 2023-04-12T19:48:50+00:00 96b1a098f3db06223a6b6268e756f980d5c07f10 Update API for bpf_xdp_metadata_rx_hash() with arg for xdp rss hash type. The veth driver currently only support XDP-hints based on SKB code path. The SKB have lost information about the RSS hash type, by compressing the information down to a single bitfield skb->l4_hash, that only knows if this was a L4 hash value. In preparation for veth, the xdp_rss_hash_type have an L4 indication bit that allow us to return a meaningful L4 indication when working with SKB based packets. Fixes: 306531f0249f ("veth: Support RX XDP metadata") Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com> Acked-by: Toke Høiland-Jørgensen <toke@redhat.com> Acked-by: Stanislav Fomichev <sdf@google.com> Link: https://lore.kernel.org/r/168132893055.340624.16209448340644513469.stgit@firesoul Signed-off-by: Alexei Starovoitov <ast@kernel.org> 
Update API for bpf_xdp_metadata_rx_hash() with arg for xdp rss hash type.

The veth driver currently only support XDP-hints based on SKB code path.
The SKB have lost information about the RSS hash type, by compressing
the information down to a single bitfield skb->l4_hash, that only knows
if this was a L4 hash value.

In preparation for veth, the xdp_rss_hash_type have an L4 indication
bit that allow us to return a meaningful L4 indication when working
with SKB based packets.

Fixes: 306531f0249f ("veth: Support RX XDP metadata")
Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
Acked-by: Toke Høiland-Jørgensen <toke@redhat.com>
Acked-by: Stanislav Fomichev <sdf@google.com>
Link: https://lore.kernel.org/r/168132893055.340624.16209448340644513469.stgit@firesoul
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
xdp: rss hash types representation 2023-04-13T18:15:10+00:00 Jesper Dangaard Brouer brouer@redhat.com 2023-04-12T19:48:40+00:00 0cd917a4a8ace70ff9082d797c899f6bf10de910 The RSS hash type specifies what portion of packet data NIC hardware used when calculating RSS hash value. The RSS types are focused on Internet traffic protocols at OSI layers L3 and L4. L2 (e.g. ARP) often get hash value zero and no RSS type. For L3 focused on IPv4 vs. IPv6, and L4 primarily TCP vs UDP, but some hardware supports SCTP. Hardware RSS types are differently encoded for each hardware NIC. Most hardware represent RSS hash type as a number. Determining L3 vs L4 often requires a mapping table as there often isn't a pattern or sorting according to ISO layer. The patch introduce a XDP RSS hash type (enum xdp_rss_hash_type) that contains both BITs for the L3/L4 types, and combinations to be used by drivers for their mapping tables. The enum xdp_rss_type_bits get exposed to BPF via BTF, and it is up to the BPF-programmer to match using these defines. This proposal change the kfunc API bpf_xdp_metadata_rx_hash() adding a pointer value argument for provide the RSS hash type. Change signature for all xmo_rx_hash calls in drivers to make it compile. The RSS type implementations for each driver comes as separate patches. Fixes: 3d76a4d3d4e5 ("bpf: XDP metadata RX kfuncs") Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com> Acked-by: Toke Høiland-Jørgensen <toke@redhat.com> Acked-by: Stanislav Fomichev <sdf@google.com> Link: https://lore.kernel.org/r/168132892042.340624.582563003880565460.stgit@firesoul Signed-off-by: Alexei Starovoitov <ast@kernel.org> 
The RSS hash type specifies what portion of packet data NIC hardware used
when calculating RSS hash value. The RSS types are focused on Internet
traffic protocols at OSI layers L3 and L4. L2 (e.g. ARP) often get hash
value zero and no RSS type. For L3 focused on IPv4 vs. IPv6, and L4
primarily TCP vs UDP, but some hardware supports SCTP.

Hardware RSS types are differently encoded for each hardware NIC. Most
hardware represent RSS hash type as a number. Determining L3 vs L4 often
requires a mapping table as there often isn't a pattern or sorting
according to ISO layer.

The patch introduce a XDP RSS hash type (enum xdp_rss_hash_type) that
contains both BITs for the L3/L4 types, and combinations to be used by
drivers for their mapping tables. The enum xdp_rss_type_bits get exposed
to BPF via BTF, and it is up to the BPF-programmer to match using these
defines.

This proposal change the kfunc API bpf_xdp_metadata_rx_hash() adding
a pointer value argument for provide the RSS hash type.
Change signature for all xmo_rx_hash calls in drivers to make it compile.

The RSS type implementations for each driver comes as separate patches.

Fixes: 3d76a4d3d4e5 ("bpf: XDP metadata RX kfuncs")
Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
Acked-by: Toke Høiland-Jørgensen <toke@redhat.com>
Acked-by: Stanislav Fomichev <sdf@google.com>
Link: https://lore.kernel.org/r/168132892042.340624.582563003880565460.stgit@firesoul
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Merge tag 'for-netdev' of https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf 2023-03-23T23:03:33+00:00 Jakub Kicinski kuba@kernel.org 2023-03-23T23:03:33+00:00 1b4ae19e432dfec785d980993c09593cbb182754 Daniel Borkmann says: ==================== pull-request: bpf 2023-03-23 We've added 8 non-merge commits during the last 13 day(s) which contain a total of 21 files changed, 238 insertions(+), 161 deletions(-). The main changes are: 1) Fix verification issues in some BPF programs due to their stack usage patterns, from Eduard Zingerman. 2) Fix to add missing overflow checks in xdp_umem_reg and return an error in such case, from Kal Conley. 3) Fix and undo poisoning of strlcpy in libbpf given it broke builds for libcs which provided the former like uClibc-ng, from Jesus Sanchez-Palencia. 4) Fix insufficient bpf_jit_limit default to avoid users running into hard to debug seccomp BPF errors, from Daniel Borkmann. 5) Fix driver return code when they don't support a bpf_xdp_metadata kfunc to make it unambiguous from other errors, from Jesper Dangaard Brouer. 6) Two BPF selftest fixes to address compilation errors from recent changes in kernel structures, from Alexei Starovoitov. * tag 'for-netdev' of https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf: xdp: bpf_xdp_metadata use EOPNOTSUPP for no driver support bpf: Adjust insufficient default bpf_jit_limit xsk: Add missing overflow check in xdp_umem_reg selftests/bpf: Fix progs/test_deny_namespace.c issues. selftests/bpf: Fix progs/find_vma_fail1.c build error. libbpf: Revert poisoning of strlcpy selftests/bpf: Tests for uninitialized stack reads bpf: Allow reads from uninit stack ==================== Link: https://lore.kernel.org/r/20230323225221.6082-1-daniel@iogearbox.net Signed-off-by: Jakub Kicinski <kuba@kernel.org> 
Daniel Borkmann says:

====================
pull-request: bpf 2023-03-23

We've added 8 non-merge commits during the last 13 day(s) which contain
a total of 21 files changed, 238 insertions(+), 161 deletions(-).

The main changes are:

1) Fix verification issues in some BPF programs due to their stack usage
   patterns, from Eduard Zingerman.

2) Fix to add missing overflow checks in xdp_umem_reg and return an error
   in such case, from Kal Conley.

3) Fix and undo poisoning of strlcpy in libbpf given it broke builds for
   libcs which provided the former like uClibc-ng, from Jesus Sanchez-Palencia.

4) Fix insufficient bpf_jit_limit default to avoid users running into hard
   to debug seccomp BPF errors, from Daniel Borkmann.

5) Fix driver return code when they don't support a bpf_xdp_metadata kfunc
   to make it unambiguous from other errors, from Jesper Dangaard Brouer.

6) Two BPF selftest fixes to address compilation errors from recent changes
   in kernel structures, from Alexei Starovoitov.

* tag 'for-netdev' of https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf:
  xdp: bpf_xdp_metadata use EOPNOTSUPP for no driver support
  bpf: Adjust insufficient default bpf_jit_limit
  xsk: Add missing overflow check in xdp_umem_reg
  selftests/bpf: Fix progs/test_deny_namespace.c issues.
  selftests/bpf: Fix progs/find_vma_fail1.c build error.
  libbpf: Revert poisoning of strlcpy
  selftests/bpf: Tests for uninitialized stack reads
  bpf: Allow reads from uninit stack
====================

Link: https://lore.kernel.org/r/20230323225221.6082-1-daniel@iogearbox.net
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
xdp: bpf_xdp_metadata use EOPNOTSUPP for no driver support 2023-03-22T16:11:09+00:00 Jesper Dangaard Brouer brouer@redhat.com 2023-03-21T13:52:31+00:00 915efd8a446b74442039d31689d5d863caf82517 When driver doesn't implement a bpf_xdp_metadata kfunc the fallback implementation returns EOPNOTSUPP, which indicate device driver doesn't implement this kfunc. Currently many drivers also return EOPNOTSUPP when the hint isn't available, which is ambiguous from an API point of view. Instead change drivers to return ENODATA in these cases. There can be natural cases why a driver doesn't provide any hardware info for a specific hint, even on a frame to frame basis (e.g. PTP). Lets keep these cases as separate return codes. When describing the return values, adjust the function kernel-doc layout to get proper rendering for the return values. Fixes: ab46182d0dcb ("net/mlx4_en: Support RX XDP metadata") Fixes: bc8d405b1ba9 ("net/mlx5e: Support RX XDP metadata") Fixes: 306531f0249f ("veth: Support RX XDP metadata") Fixes: 3d76a4d3d4e5 ("bpf: XDP metadata RX kfuncs") Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com> Acked-by: Stanislav Fomichev <sdf@google.com> Acked-by: Toke Høiland-Jørgensen <toke@redhat.com> Acked-by: Tariq Toukan <tariqt@nvidia.com> Link: https://lore.kernel.org/r/167940675120.2718408.8176058626864184420.stgit@firesoul Signed-off-by: Alexei Starovoitov <ast@kernel.org> 
When driver doesn't implement a bpf_xdp_metadata kfunc the fallback
implementation returns EOPNOTSUPP, which indicate device driver doesn't
implement this kfunc.

Currently many drivers also return EOPNOTSUPP when the hint isn't
available, which is ambiguous from an API point of view. Instead
change drivers to return ENODATA in these cases.

There can be natural cases why a driver doesn't provide any hardware
info for a specific hint, even on a frame to frame basis (e.g. PTP).
Lets keep these cases as separate return codes.

When describing the return values, adjust the function kernel-doc layout
to get proper rendering for the return values.

Fixes: ab46182d0dcb ("net/mlx4_en: Support RX XDP metadata")
Fixes: bc8d405b1ba9 ("net/mlx5e: Support RX XDP metadata")
Fixes: 306531f0249f ("veth: Support RX XDP metadata")
Fixes: 3d76a4d3d4e5 ("bpf: XDP metadata RX kfuncs")
Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
Acked-by: Stanislav Fomichev <sdf@google.com>
Acked-by: Toke Høiland-Jørgensen <toke@redhat.com>
Acked-by: Tariq Toukan <tariqt@nvidia.com>
Link: https://lore.kernel.org/r/167940675120.2718408.8176058626864184420.stgit@firesoul
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
veth: Fix use after free in XDP_REDIRECT 2023-03-16T04:11:06+00:00 Shawn Bohrer sbohrer@cloudflare.com 2023-03-14T15:33:51+00:00 7c10131803e45269ddc6c817f19ed649110f3cae Commit 718a18a0c8a6 ("veth: Rework veth_xdp_rcv_skb in order to accept non-linear skb") introduced a bug where it tried to use pskb_expand_head() if the headroom was less than XDP_PACKET_HEADROOM. This however uses kmalloc to expand the head, which will later allow consume_skb() to free the skb while is it still in use by AF_XDP. Previously if the headroom was less than XDP_PACKET_HEADROOM we continued on to allocate a new skb from pages so this restores that behavior. BUG: KASAN: use-after-free in __xsk_rcv+0x18d/0x2c0 Read of size 78 at addr ffff888976250154 by task napi/iconduit-g/148640 CPU: 5 PID: 148640 Comm: napi/iconduit-g Kdump: loaded Tainted: G O 6.1.4-cloudflare-kasan-2023.1.2 #1 Hardware name: Quanta Computer Inc. QuantaPlex T41S-2U/S2S-MB, BIOS S2S_3B10.03 06/21/2018 Call Trace: <TASK> dump_stack_lvl+0x34/0x48 print_report+0x170/0x473 ? __xsk_rcv+0x18d/0x2c0 kasan_report+0xad/0x130 ? __xsk_rcv+0x18d/0x2c0 kasan_check_range+0x149/0x1a0 memcpy+0x20/0x60 __xsk_rcv+0x18d/0x2c0 __xsk_map_redirect+0x1f3/0x490 ? veth_xdp_rcv_skb+0x89c/0x1ba0 [veth] xdp_do_redirect+0x5ca/0xd60 veth_xdp_rcv_skb+0x935/0x1ba0 [veth] ? __netif_receive_skb_list_core+0x671/0x920 ? veth_xdp+0x670/0x670 [veth] veth_xdp_rcv+0x304/0xa20 [veth] ? do_xdp_generic+0x150/0x150 ? veth_xdp_rcv_one+0xde0/0xde0 [veth] ? _raw_spin_lock_bh+0xe0/0xe0 ? newidle_balance+0x887/0xe30 ? __perf_event_task_sched_in+0xdb/0x800 veth_poll+0x139/0x571 [veth] ? veth_xdp_rcv+0xa20/0xa20 [veth] ? _raw_spin_unlock+0x39/0x70 ? finish_task_switch.isra.0+0x17e/0x7d0 ? __switch_to+0x5cf/0x1070 ? __schedule+0x95b/0x2640 ? io_schedule_timeout+0x160/0x160 __napi_poll+0xa1/0x440 napi_threaded_poll+0x3d1/0x460 ? __napi_poll+0x440/0x440 ? __kthread_parkme+0xc6/0x1f0 ? __napi_poll+0x440/0x440 kthread+0x2a2/0x340 ? kthread_complete_and_exit+0x20/0x20 ret_from_fork+0x22/0x30 </TASK> Freed by task 148640: kasan_save_stack+0x23/0x50 kasan_set_track+0x21/0x30 kasan_save_free_info+0x2a/0x40 ____kasan_slab_free+0x169/0x1d0 slab_free_freelist_hook+0xd2/0x190 __kmem_cache_free+0x1a1/0x2f0 skb_release_data+0x449/0x600 consume_skb+0x9f/0x1c0 veth_xdp_rcv_skb+0x89c/0x1ba0 [veth] veth_xdp_rcv+0x304/0xa20 [veth] veth_poll+0x139/0x571 [veth] __napi_poll+0xa1/0x440 napi_threaded_poll+0x3d1/0x460 kthread+0x2a2/0x340 ret_from_fork+0x22/0x30 The buggy address belongs to the object at ffff888976250000 which belongs to the cache kmalloc-2k of size 2048 The buggy address is located 340 bytes inside of 2048-byte region [ffff888976250000, ffff888976250800) The buggy address belongs to the physical page: page:00000000ae18262a refcount:2 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x976250 head:00000000ae18262a order:3 compound_mapcount:0 compound_pincount:0 flags: 0x2ffff800010200(slab|head|node=0|zone=2|lastcpupid=0x1ffff) raw: 002ffff800010200 0000000000000000 dead000000000122 ffff88810004cf00 raw: 0000000000000000 0000000080080008 00000002ffffffff 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff888976250000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888976250080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb > ffff888976250100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888976250180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888976250200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb Fixes: 718a18a0c8a6 ("veth: Rework veth_xdp_rcv_skb in order to accept non-linear skb") Signed-off-by: Shawn Bohrer <sbohrer@cloudflare.com> Acked-by: Lorenzo Bianconi <lorenzo@kernel.org> Acked-by: Toshiaki Makita <toshiaki.makita1@gmail.com> Acked-by: Toke Høiland-Jørgensen <toke@kernel.org> Link: https://lore.kernel.org/r/20230314153351.2201328-1-sbohrer@cloudflare.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> 
Commit 718a18a0c8a6 ("veth: Rework veth_xdp_rcv_skb in order
to accept non-linear skb") introduced a bug where it tried to
use pskb_expand_head() if the headroom was less than
XDP_PACKET_HEADROOM.  This however uses kmalloc to expand the head,
which will later allow consume_skb() to free the skb while is it still
in use by AF_XDP.

Previously if the headroom was less than XDP_PACKET_HEADROOM we
continued on to allocate a new skb from pages so this restores that
behavior.

BUG: KASAN: use-after-free in __xsk_rcv+0x18d/0x2c0
Read of size 78 at addr ffff888976250154 by task napi/iconduit-g/148640

CPU: 5 PID: 148640 Comm: napi/iconduit-g Kdump: loaded Tainted: G           O       6.1.4-cloudflare-kasan-2023.1.2 #1
Hardware name: Quanta Computer Inc. QuantaPlex T41S-2U/S2S-MB, BIOS S2S_3B10.03 06/21/2018
Call Trace:
  <TASK>
  dump_stack_lvl+0x34/0x48
  print_report+0x170/0x473
  ? __xsk_rcv+0x18d/0x2c0
  kasan_report+0xad/0x130
  ? __xsk_rcv+0x18d/0x2c0
  kasan_check_range+0x149/0x1a0
  memcpy+0x20/0x60
  __xsk_rcv+0x18d/0x2c0
  __xsk_map_redirect+0x1f3/0x490
  ? veth_xdp_rcv_skb+0x89c/0x1ba0 [veth]
  xdp_do_redirect+0x5ca/0xd60
  veth_xdp_rcv_skb+0x935/0x1ba0 [veth]
  ? __netif_receive_skb_list_core+0x671/0x920
  ? veth_xdp+0x670/0x670 [veth]
  veth_xdp_rcv+0x304/0xa20 [veth]
  ? do_xdp_generic+0x150/0x150
  ? veth_xdp_rcv_one+0xde0/0xde0 [veth]
  ? _raw_spin_lock_bh+0xe0/0xe0
  ? newidle_balance+0x887/0xe30
  ? __perf_event_task_sched_in+0xdb/0x800
  veth_poll+0x139/0x571 [veth]
  ? veth_xdp_rcv+0xa20/0xa20 [veth]
  ? _raw_spin_unlock+0x39/0x70
  ? finish_task_switch.isra.0+0x17e/0x7d0
  ? __switch_to+0x5cf/0x1070
  ? __schedule+0x95b/0x2640
  ? io_schedule_timeout+0x160/0x160
  __napi_poll+0xa1/0x440
  napi_threaded_poll+0x3d1/0x460
  ? __napi_poll+0x440/0x440
  ? __kthread_parkme+0xc6/0x1f0
  ? __napi_poll+0x440/0x440
  kthread+0x2a2/0x340
  ? kthread_complete_and_exit+0x20/0x20
  ret_from_fork+0x22/0x30
  </TASK>

Freed by task 148640:
  kasan_save_stack+0x23/0x50
  kasan_set_track+0x21/0x30
  kasan_save_free_info+0x2a/0x40
  ____kasan_slab_free+0x169/0x1d0
  slab_free_freelist_hook+0xd2/0x190
  __kmem_cache_free+0x1a1/0x2f0
  skb_release_data+0x449/0x600
  consume_skb+0x9f/0x1c0
  veth_xdp_rcv_skb+0x89c/0x1ba0 [veth]
  veth_xdp_rcv+0x304/0xa20 [veth]
  veth_poll+0x139/0x571 [veth]
  __napi_poll+0xa1/0x440
  napi_threaded_poll+0x3d1/0x460
  kthread+0x2a2/0x340
  ret_from_fork+0x22/0x30

The buggy address belongs to the object at ffff888976250000
  which belongs to the cache kmalloc-2k of size 2048
The buggy address is located 340 bytes inside of
  2048-byte region [ffff888976250000, ffff888976250800)

The buggy address belongs to the physical page:
page:00000000ae18262a refcount:2 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x976250
head:00000000ae18262a order:3 compound_mapcount:0 compound_pincount:0
flags: 0x2ffff800010200(slab|head|node=0|zone=2|lastcpupid=0x1ffff)
raw: 002ffff800010200 0000000000000000 dead000000000122 ffff88810004cf00
raw: 0000000000000000 0000000080080008 00000002ffffffff 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
  ffff888976250000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
  ffff888976250080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
> ffff888976250100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                                  ^
  ffff888976250180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
  ffff888976250200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb

Fixes: 718a18a0c8a6 ("veth: Rework veth_xdp_rcv_skb in order to accept non-linear skb")
Signed-off-by: Shawn Bohrer <sbohrer@cloudflare.com>
Acked-by: Lorenzo Bianconi <lorenzo@kernel.org>
Acked-by: Toshiaki Makita <toshiaki.makita1@gmail.com>
Acked-by: Toke Høiland-Jørgensen <toke@kernel.org>
Link: https://lore.kernel.org/r/20230314153351.2201328-1-sbohrer@cloudflare.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
veth: rely on rtnl_dereference() instead of on rcu_dereference() in veth_set_xdp_features() 2023-03-15T07:38:33+00:00 Lorenzo Bianconi lorenzo@kernel.org 2023-03-13T23:08:40+00:00 5ce76fe1eead179c058d9151ee1f4088cfdc1c6b Fix the following kernel warning in veth_set_xdp_features routine relying on rtnl_dereference() instead of on rcu_dereference(): ============================= WARNING: suspicious RCU usage 6.3.0-rc1-00144-g064d70527aaa #149 Not tainted ----------------------------- drivers/net/veth.c:1265 suspicious rcu_dereference_check() usage! other info that might help us debug this: rcu_scheduler_active = 2, debug_locks = 1 1 lock held by ip/135: (net/core/rtnetlink.c:6172) stack backtrace: CPU: 1 PID: 135 Comm: ip Not tainted 6.3.0-rc1-00144-g064d70527aaa #149 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.15.0-1 04/01/2014 Call Trace: <TASK> dump_stack_lvl (lib/dump_stack.c:107) lockdep_rcu_suspicious (include/linux/context_tracking.h:152) veth_set_xdp_features (drivers/net/veth.c:1265 (discriminator 9)) veth_newlink (drivers/net/veth.c:1892) ? veth_set_features (drivers/net/veth.c:1774) ? kasan_save_stack (mm/kasan/common.c:47) ? kasan_save_stack (mm/kasan/common.c:46) ? kasan_set_track (mm/kasan/common.c:52) ? alloc_netdev_mqs (include/linux/slab.h:737) ? rcu_read_lock_sched_held (kernel/rcu/update.c:125) ? trace_kmalloc (include/trace/events/kmem.h:54) ? __xdp_rxq_info_reg (net/core/xdp.c:188) ? alloc_netdev_mqs (net/core/dev.c:10657) ? rtnl_create_link (net/core/rtnetlink.c:3312) rtnl_newlink_create (net/core/rtnetlink.c:3440) ? rtnl_link_get_net_capable.constprop.0 (net/core/rtnetlink.c:3391) __rtnl_newlink (net/core/rtnetlink.c:3657) ? lock_downgrade (kernel/locking/lockdep.c:5321) ? rtnl_link_unregister (net/core/rtnetlink.c:3487) rtnl_newlink (net/core/rtnetlink.c:3671) rtnetlink_rcv_msg (net/core/rtnetlink.c:6174) ? rtnl_link_fill (net/core/rtnetlink.c:6070) ? mark_usage (kernel/locking/lockdep.c:4914) ? mark_usage (kernel/locking/lockdep.c:4914) netlink_rcv_skb (net/netlink/af_netlink.c:2574) ? rtnl_link_fill (net/core/rtnetlink.c:6070) ? netlink_ack (net/netlink/af_netlink.c:2551) ? lock_acquire (kernel/locking/lockdep.c:467) ? net_generic (include/linux/rcupdate.h:805) ? netlink_deliver_tap (include/linux/rcupdate.h:805) netlink_unicast (net/netlink/af_netlink.c:1340) ? netlink_attachskb (net/netlink/af_netlink.c:1350) netlink_sendmsg (net/netlink/af_netlink.c:1942) ? netlink_unicast (net/netlink/af_netlink.c:1861) ? netlink_unicast (net/netlink/af_netlink.c:1861) sock_sendmsg (net/socket.c:727) ____sys_sendmsg (net/socket.c:2501) ? kernel_sendmsg (net/socket.c:2448) ? __copy_msghdr (net/socket.c:2428) ___sys_sendmsg (net/socket.c:2557) ? mark_usage (kernel/locking/lockdep.c:4914) ? do_recvmmsg (net/socket.c:2544) ? lock_acquire (kernel/locking/lockdep.c:467) ? find_held_lock (kernel/locking/lockdep.c:5159) ? __lock_release (kernel/locking/lockdep.c:5345) ? __might_fault (mm/memory.c:5625) ? lock_downgrade (kernel/locking/lockdep.c:5321) ? __fget_light (include/linux/atomic/atomic-arch-fallback.h:227) __sys_sendmsg (include/linux/file.h:31) ? __sys_sendmsg_sock (net/socket.c:2572) ? rseq_get_rseq_cs (kernel/rseq.c:275) ? lockdep_hardirqs_on_prepare.part.0 (kernel/locking/lockdep.c:4263) do_syscall_64 (arch/x86/entry/common.c:50) entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:120) RIP: 0033:0x7f0d1aadeb17 Code: 0f 00 f7 d8 64 89 02 48 c7 c0 ff ff ff ff eb b9 0f 1f 00 f3 0f 1e fa 64 8b 04 25 18 00 00 00 85 c0 75 10 b8 2e 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 51 c3 48 83 ec 28 89 54 24 1c 48 89 74 24 10 Fixes: fccca038f300 ("veth: take into account device reconfiguration for xdp_features flag") Suggested-by: Eric Dumazet <edumazet@google.com> Reported-by: Matthieu Baerts <matthieu.baerts@tessares.net> Link: https://lore.kernel.org/netdev/cover.1678364612.git.lorenzo@kernel.org/T/#me4c9d8e985ec7ebee981cfdb5bc5ec651ef4035d Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org> Reported-by: syzbot+c3d0d9c42d59ff644ea6@syzkaller.appspotmail.com Reviewed-by: Eric Dumazet <edumazet@google.com> Tested-by: Matthieu Baerts <matthieu.baerts@tessares.net> Link: https://lore.kernel.org/r/dfd6a9a7d85e9113063165e1f47b466b90ad7b8a.1678748579.git.lorenzo@kernel.org Signed-off-by: Jakub Kicinski <kuba@kernel.org> 
Fix the following kernel warning in veth_set_xdp_features routine
relying on rtnl_dereference() instead of on rcu_dereference():

=============================
WARNING: suspicious RCU usage
6.3.0-rc1-00144-g064d70527aaa #149 Not tainted
-----------------------------
drivers/net/veth.c:1265 suspicious rcu_dereference_check() usage!

other info that might help us debug this:

rcu_scheduler_active = 2, debug_locks = 1
1 lock held by ip/135:
(net/core/rtnetlink.c:6172)

stack backtrace:
CPU: 1 PID: 135 Comm: ip Not tainted 6.3.0-rc1-00144-g064d70527aaa #149
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.15.0-1
04/01/2014
Call Trace:
 <TASK>
dump_stack_lvl (lib/dump_stack.c:107)
lockdep_rcu_suspicious (include/linux/context_tracking.h:152)
veth_set_xdp_features (drivers/net/veth.c:1265 (discriminator 9))
veth_newlink (drivers/net/veth.c:1892)
? veth_set_features (drivers/net/veth.c:1774)
? kasan_save_stack (mm/kasan/common.c:47)
? kasan_save_stack (mm/kasan/common.c:46)
? kasan_set_track (mm/kasan/common.c:52)
? alloc_netdev_mqs (include/linux/slab.h:737)
? rcu_read_lock_sched_held (kernel/rcu/update.c:125)
? trace_kmalloc (include/trace/events/kmem.h:54)
? __xdp_rxq_info_reg (net/core/xdp.c:188)
? alloc_netdev_mqs (net/core/dev.c:10657)
? rtnl_create_link (net/core/rtnetlink.c:3312)
rtnl_newlink_create (net/core/rtnetlink.c:3440)
? rtnl_link_get_net_capable.constprop.0 (net/core/rtnetlink.c:3391)
__rtnl_newlink (net/core/rtnetlink.c:3657)
? lock_downgrade (kernel/locking/lockdep.c:5321)
? rtnl_link_unregister (net/core/rtnetlink.c:3487)
rtnl_newlink (net/core/rtnetlink.c:3671)
rtnetlink_rcv_msg (net/core/rtnetlink.c:6174)
? rtnl_link_fill (net/core/rtnetlink.c:6070)
? mark_usage (kernel/locking/lockdep.c:4914)
? mark_usage (kernel/locking/lockdep.c:4914)
netlink_rcv_skb (net/netlink/af_netlink.c:2574)
? rtnl_link_fill (net/core/rtnetlink.c:6070)
? netlink_ack (net/netlink/af_netlink.c:2551)
? lock_acquire (kernel/locking/lockdep.c:467)
? net_generic (include/linux/rcupdate.h:805)
? netlink_deliver_tap (include/linux/rcupdate.h:805)
netlink_unicast (net/netlink/af_netlink.c:1340)
? netlink_attachskb (net/netlink/af_netlink.c:1350)
netlink_sendmsg (net/netlink/af_netlink.c:1942)
? netlink_unicast (net/netlink/af_netlink.c:1861)
? netlink_unicast (net/netlink/af_netlink.c:1861)
sock_sendmsg (net/socket.c:727)
____sys_sendmsg (net/socket.c:2501)
? kernel_sendmsg (net/socket.c:2448)
? __copy_msghdr (net/socket.c:2428)
___sys_sendmsg (net/socket.c:2557)
? mark_usage (kernel/locking/lockdep.c:4914)
? do_recvmmsg (net/socket.c:2544)
? lock_acquire (kernel/locking/lockdep.c:467)
? find_held_lock (kernel/locking/lockdep.c:5159)
? __lock_release (kernel/locking/lockdep.c:5345)
? __might_fault (mm/memory.c:5625)
? lock_downgrade (kernel/locking/lockdep.c:5321)
? __fget_light (include/linux/atomic/atomic-arch-fallback.h:227)
__sys_sendmsg (include/linux/file.h:31)
? __sys_sendmsg_sock (net/socket.c:2572)
? rseq_get_rseq_cs (kernel/rseq.c:275)
? lockdep_hardirqs_on_prepare.part.0 (kernel/locking/lockdep.c:4263)
do_syscall_64 (arch/x86/entry/common.c:50)
entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:120)
RIP: 0033:0x7f0d1aadeb17
Code: 0f 00 f7 d8 64 89 02 48 c7 c0 ff ff ff ff eb b9 0f 1f 00 f3 0f 1e
fa 64 8b 04 25 18 00 00 00 85 c0 75 10 b8 2e 00 00 00 0f 05 <48> 3d 00
f0 ff ff 77 51 c3 48 83 ec 28 89 54 24 1c 48 89 74 24 10

Fixes: fccca038f300 ("veth: take into account device reconfiguration for xdp_features flag")
Suggested-by: Eric Dumazet <edumazet@google.com>
Reported-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Link: https://lore.kernel.org/netdev/cover.1678364612.git.lorenzo@kernel.org/T/#me4c9d8e985ec7ebee981cfdb5bc5ec651ef4035d
Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
Reported-by: syzbot+c3d0d9c42d59ff644ea6@syzkaller.appspotmail.com
Reviewed-by: Eric Dumazet <edumazet@google.com>
Tested-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Link: https://lore.kernel.org/r/dfd6a9a7d85e9113063165e1f47b466b90ad7b8a.1678748579.git.lorenzo@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
veth: take into account device reconfiguration for xdp_features flag 2023-03-11T05:33:48+00:00 Lorenzo Bianconi lorenzo@kernel.org 2023-03-09T12:25:30+00:00 fccca038f3003daa8f28a5e5d97efe50f04b8d9d Take into account tx/rx queues reconfiguration setting device xdp_features flag. Moreover consider NETIF_F_GRO flag in order to enable ndo_xdp_xmit callback. Fixes: 66c0e13ad236 ("drivers: net: turn on XDP features") Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org> Signed-off-by: Jakub Kicinski <kuba@kernel.org> 
Take into account tx/rx queues reconfiguration setting device
xdp_features flag. Moreover consider NETIF_F_GRO flag in order to enable
ndo_xdp_xmit callback.

Fixes: 66c0e13ad236 ("drivers: net: turn on XDP features")
Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
drivers: net: turn on XDP features 2023-02-03T04:48:23+00:00 Marek Majtyka alardam@gmail.com 2023-02-01T10:24:18+00:00 66c0e13ad236c74ea88c7c1518f3cef7f372e3da A summary of the flags being set for various drivers is given below. Note that XDP_F_REDIRECT_TARGET and XDP_F_FRAG_TARGET are features that can be turned off and on at runtime. This means that these flags may be set and unset under RTNL lock protection by the driver. Hence, READ_ONCE must be used by code loading the flag value. Also, these flags are not used for synchronization against the availability of XDP resources on a device. It is merely a hint, and hence the read may race with the actual teardown of XDP resources on the device. This may change in the future, e.g. operations taking a reference on the XDP resources of the driver, and in turn inhibiting turning off this flag. However, for now, it can only be used as a hint to check whether device supports becoming a redirection target. Turn 'hw-offload' feature flag on for: - netronome (nfp) - netdevsim. Turn 'native' and 'zerocopy' features flags on for: - intel (i40e, ice, ixgbe, igc) - mellanox (mlx5). - stmmac - netronome (nfp) Turn 'native' features flags on for: - amazon (ena) - broadcom (bnxt) - freescale (dpaa, dpaa2, enetc) - funeth - intel (igb) - marvell (mvneta, mvpp2, octeontx2) - mellanox (mlx4) - mtk_eth_soc - qlogic (qede) - sfc - socionext (netsec) - ti (cpsw) - tap - tsnep - veth - xen - virtio_net. Turn 'basic' (tx, pass, aborted and drop) features flags on for: - netronome (nfp) - cavium (thunder) - hyperv. Turn 'redirect_target' feature flag on for: - amanzon (ena) - broadcom (bnxt) - freescale (dpaa, dpaa2) - intel (i40e, ice, igb, ixgbe) - ti (cpsw) - marvell (mvneta, mvpp2) - sfc - socionext (netsec) - qlogic (qede) - mellanox (mlx5) - tap - veth - virtio_net - xen Reviewed-by: Gerhard Engleder <gerhard@engleder-embedded.com> Reviewed-by: Simon Horman <simon.horman@corigine.com> Acked-by: Stanislav Fomichev <sdf@google.com> Acked-by: Jakub Kicinski <kuba@kernel.org> Co-developed-by: Kumar Kartikeya Dwivedi <memxor@gmail.com> Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com> Co-developed-by: Lorenzo Bianconi <lorenzo@kernel.org> Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org> Signed-off-by: Marek Majtyka <alardam@gmail.com> Link: https://lore.kernel.org/r/3eca9fafb308462f7edb1f58e451d59209aa07eb.1675245258.git.lorenzo@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> 
A summary of the flags being set for various drivers is given below.
Note that XDP_F_REDIRECT_TARGET and XDP_F_FRAG_TARGET are features
that can be turned off and on at runtime. This means that these flags
may be set and unset under RTNL lock protection by the driver. Hence,
READ_ONCE must be used by code loading the flag value.

Also, these flags are not used for synchronization against the availability
of XDP resources on a device. It is merely a hint, and hence the read
may race with the actual teardown of XDP resources on the device. This
may change in the future, e.g. operations taking a reference on the XDP
resources of the driver, and in turn inhibiting turning off this flag.
However, for now, it can only be used as a hint to check whether device
supports becoming a redirection target.

Turn 'hw-offload' feature flag on for:
 - netronome (nfp)
 - netdevsim.

Turn 'native' and 'zerocopy' features flags on for:
 - intel (i40e, ice, ixgbe, igc)
 - mellanox (mlx5).
 - stmmac
 - netronome (nfp)

Turn 'native' features flags on for:
 - amazon (ena)
 - broadcom (bnxt)
 - freescale (dpaa, dpaa2, enetc)
 - funeth
 - intel (igb)
 - marvell (mvneta, mvpp2, octeontx2)
 - mellanox (mlx4)
 - mtk_eth_soc
 - qlogic (qede)
 - sfc
 - socionext (netsec)
 - ti (cpsw)
 - tap
 - tsnep
 - veth
 - xen
 - virtio_net.

Turn 'basic' (tx, pass, aborted and drop) features flags on for:
 - netronome (nfp)
 - cavium (thunder)
 - hyperv.

Turn 'redirect_target' feature flag on for:
 - amanzon (ena)
 - broadcom (bnxt)
 - freescale (dpaa, dpaa2)
 - intel (i40e, ice, igb, ixgbe)
 - ti (cpsw)
 - marvell (mvneta, mvpp2)
 - sfc
 - socionext (netsec)
 - qlogic (qede)
 - mellanox (mlx5)
 - tap
 - veth
 - virtio_net
 - xen

Reviewed-by: Gerhard Engleder <gerhard@engleder-embedded.com>
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Acked-by: Stanislav Fomichev <sdf@google.com>
Acked-by: Jakub Kicinski <kuba@kernel.org>
Co-developed-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Co-developed-by: Lorenzo Bianconi <lorenzo@kernel.org>
Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
Signed-off-by: Marek Majtyka <alardam@gmail.com>
Link: https://lore.kernel.org/r/3eca9fafb308462f7edb1f58e451d59209aa07eb.1675245258.git.lorenzo@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
veth: Support RX XDP metadata 2023-01-23T17:38:11+00:00 Stanislav Fomichev sdf@google.com 2023-01-19T22:15:29+00:00 306531f0249f4e1c1aabaa0d70d24a1e9c71e38b The goal is to enable end-to-end testing of the metadata for AF_XDP. Cc: John Fastabend <john.fastabend@gmail.com> Cc: David Ahern <dsahern@gmail.com> Cc: Martin KaFai Lau <martin.lau@linux.dev> Cc: Jakub Kicinski <kuba@kernel.org> Cc: Willem de Bruijn <willemb@google.com> Cc: Jesper Dangaard Brouer <brouer@redhat.com> Cc: Anatoly Burakov <anatoly.burakov@intel.com> Cc: Alexander Lobakin <alexandr.lobakin@intel.com> Cc: Magnus Karlsson <magnus.karlsson@gmail.com> Cc: Maryam Tahhan <mtahhan@redhat.com> Cc: xdp-hints@xdp-project.net Cc: netdev@vger.kernel.org Signed-off-by: Stanislav Fomichev <sdf@google.com> Link: https://lore.kernel.org/r/20230119221536.3349901-11-sdf@google.com Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org> 
The goal is to enable end-to-end testing of the metadata for AF_XDP.

Cc: John Fastabend <john.fastabend@gmail.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Martin KaFai Lau <martin.lau@linux.dev>
Cc: Jakub Kicinski <kuba@kernel.org>
Cc: Willem de Bruijn <willemb@google.com>
Cc: Jesper Dangaard Brouer <brouer@redhat.com>
Cc: Anatoly Burakov <anatoly.burakov@intel.com>
Cc: Alexander Lobakin <alexandr.lobakin@intel.com>
Cc: Magnus Karlsson <magnus.karlsson@gmail.com>
Cc: Maryam Tahhan <mtahhan@redhat.com>
Cc: xdp-hints@xdp-project.net
Cc: netdev@vger.kernel.org
Signed-off-by: Stanislav Fomichev <sdf@google.com>
Link: https://lore.kernel.org/r/20230119221536.3349901-11-sdf@google.com
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>