linux.git/net/xdp, branch v5.12 Linux kernel source tree xsk: Fold xp_assign_dev and __xp_assign_dev 2021-01-25T22:56:33+00:00 Björn Töpel bjorn.topel@intel.com 2021-01-22T10:53:50+00:00 f0863eab966b95f46f96708b25996c6615856484 Fold xp_assign_dev and __xp_assign_dev. The former directly calls the latter. Signed-off-by: Björn Töpel <bjorn.topel@intel.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Reviewed-by: Maciej Fijalkowski <maciej.fijalkowski@intel.com> Link: https://lore.kernel.org/bpf/20210122105351.11751-3-bjorn.topel@gmail.com 
Fold xp_assign_dev and __xp_assign_dev. The former directly calls the
latter.

Signed-off-by: Björn Töpel <bjorn.topel@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Maciej Fijalkowski <maciej.fijalkowski@intel.com>
Link: https://lore.kernel.org/bpf/20210122105351.11751-3-bjorn.topel@gmail.com
xsk: Remove explicit_free parameter from __xsk_rcv() 2021-01-25T22:56:33+00:00 Björn Töpel bjorn.topel@intel.com 2021-01-22T10:53:49+00:00 458f7272341265e443c227ba55ee4a338021a60a The explicit_free parameter of the __xsk_rcv() function was used to mark whether the call was via the generic XDP or the native XDP path. Instead of clutter the code with if-statements and "true/false" parameters which are hard to understand, simply move the explicit free to the __xsk_map_redirect() which is always called from the native XDP path. Signed-off-by: Björn Töpel <bjorn.topel@intel.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Reviewed-by: Maciej Fijalkowski <maciej.fijalkowski@intel.com> Link: https://lore.kernel.org/bpf/20210122105351.11751-2-bjorn.topel@gmail.com 
The explicit_free parameter of the __xsk_rcv() function was used to
mark whether the call was via the generic XDP or the native XDP
path. Instead of clutter the code with if-statements and "true/false"
parameters which are hard to understand, simply move the explicit free
to the __xsk_map_redirect() which is always called from the native XDP
path.

Signed-off-by: Björn Töpel <bjorn.topel@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Maciej Fijalkowski <maciej.fijalkowski@intel.com>
Link: https://lore.kernel.org/bpf/20210122105351.11751-2-bjorn.topel@gmail.com
xsk: Clear pool even for inactive queues 2021-01-19T21:47:04+00:00 Maxim Mikityanskiy maximmi@mellanox.com 2021-01-18T16:03:33+00:00 b425e24a934e21a502d25089c6c7443d799c5594 The number of queues can change by other means, rather than ethtool. For example, attaching an mqprio qdisc with num_tc > 1 leads to creating multiple sets of TX queues, which may be then destroyed when mqprio is deleted. If an AF_XDP socket is created while mqprio is active, dev->_tx[queue_id].pool will be filled, but then real_num_tx_queues may decrease with deletion of mqprio, which will mean that the pool won't be NULLed, and a further increase of the number of TX queues may expose a dangling pointer. To avoid any potential misbehavior, this commit clears pool for RX and TX queues, regardless of real_num_*_queues, still taking into consideration num_*_queues to avoid overflows. Fixes: 1c1efc2af158 ("xsk: Create and free buffer pool independently from umem") Fixes: a41b4f3c58dd ("xsk: simplify xdp_clear_umem_at_qid implementation") Signed-off-by: Maxim Mikityanskiy <maximmi@mellanox.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Björn Töpel <bjorn.topel@intel.com> Link: https://lore.kernel.org/bpf/20210118160333.333439-1-maximmi@mellanox.com 
The number of queues can change by other means, rather than ethtool. For
example, attaching an mqprio qdisc with num_tc > 1 leads to creating
multiple sets of TX queues, which may be then destroyed when mqprio is
deleted. If an AF_XDP socket is created while mqprio is active,
dev->_tx[queue_id].pool will be filled, but then real_num_tx_queues may
decrease with deletion of mqprio, which will mean that the pool won't be
NULLed, and a further increase of the number of TX queues may expose a
dangling pointer.

To avoid any potential misbehavior, this commit clears pool for RX and
TX queues, regardless of real_num_*_queues, still taking into
consideration num_*_queues to avoid overflows.

Fixes: 1c1efc2af158 ("xsk: Create and free buffer pool independently from umem")
Fixes: a41b4f3c58dd ("xsk: simplify xdp_clear_umem_at_qid implementation")
Signed-off-by: Maxim Mikityanskiy <maximmi@mellanox.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Björn Töpel <bjorn.topel@intel.com>
Link: https://lore.kernel.org/bpf/20210118160333.333439-1-maximmi@mellanox.com
xsk: Rollback reservation at NETDEV_TX_BUSY 2020-12-18T15:10:21+00:00 Magnus Karlsson magnus.karlsson@intel.com 2020-12-18T13:45:25+00:00 b1b95cb5c0a9694d47d5f845ba97e226cfda957d Rollback the reservation in the completion ring when we get a NETDEV_TX_BUSY. When this error is received from the driver, we are supposed to let the user application retry the transmit again. And in order to do this, we need to roll back the failed send so it can be retried. Unfortunately, we did not cancel the reservation we had made in the completion ring. By not doing this, we actually make the completion ring one entry smaller per NETDEV_TX_BUSY error we get, and after enough of these errors the completion ring will be of size zero and transmit will stop working. Fix this by cancelling the reservation when we get a NETDEV_TX_BUSY error. Fixes: 642e450b6b59 ("xsk: Do not discard packet when NETDEV_TX_BUSY") Reported-by: Xuan Zhuo <xuanzhuo@linux.alibaba.com> Signed-off-by: Magnus Karlsson <magnus.karlsson@intel.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Björn Töpel <bjorn.topel@intel.com> Link: https://lore.kernel.org/bpf/20201218134525.13119-3-magnus.karlsson@gmail.com 
Rollback the reservation in the completion ring when we get a
NETDEV_TX_BUSY. When this error is received from the driver, we are
supposed to let the user application retry the transmit again. And in
order to do this, we need to roll back the failed send so it can be
retried. Unfortunately, we did not cancel the reservation we had made
in the completion ring. By not doing this, we actually make the
completion ring one entry smaller per NETDEV_TX_BUSY error we get, and
after enough of these errors the completion ring will be of size zero
and transmit will stop working.

Fix this by cancelling the reservation when we get a NETDEV_TX_BUSY
error.

Fixes: 642e450b6b59 ("xsk: Do not discard packet when NETDEV_TX_BUSY")
Reported-by: Xuan Zhuo <xuanzhuo@linux.alibaba.com>
Signed-off-by: Magnus Karlsson <magnus.karlsson@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Björn Töpel <bjorn.topel@intel.com>
Link: https://lore.kernel.org/bpf/20201218134525.13119-3-magnus.karlsson@gmail.com
xsk: Fix race in SKB mode transmit with shared cq 2020-12-18T15:10:21+00:00 Magnus Karlsson magnus.karlsson@intel.com 2020-12-18T13:45:24+00:00 f09ced4053bc0a2094a12b60b646114c966ef4c6 Fix a race when multiple sockets are simultaneously calling sendto() when the completion ring is shared in the SKB case. This is the case when you share the same netdev and queue id through the XDP_SHARED_UMEM bind flag. The problem is that multiple processes can be in xsk_generic_xmit() and call the backpressure mechanism in xskq_prod_reserve(xs->pool->cq). As this is a shared resource in this specific scenario, a race might occur since the rings are single-producer single-consumer. Fix this by moving the tx_completion_lock from the socket to the pool as the pool is shared between the sockets that share the completion ring. (The pool is not shared when this is not the case.) And then protect the accesses to xskq_prod_reserve() with this lock. The tx_completion_lock is renamed cq_lock to better reflect that it protects accesses to the potentially shared completion ring. Fixes: 35fcde7f8deb ("xsk: support for Tx") Reported-by: Xuan Zhuo <xuanzhuo@linux.alibaba.com> Signed-off-by: Magnus Karlsson <magnus.karlsson@intel.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Björn Töpel <bjorn.topel@intel.com> Link: https://lore.kernel.org/bpf/20201218134525.13119-2-magnus.karlsson@gmail.com 
Fix a race when multiple sockets are simultaneously calling sendto()
when the completion ring is shared in the SKB case. This is the case
when you share the same netdev and queue id through the
XDP_SHARED_UMEM bind flag. The problem is that multiple processes can
be in xsk_generic_xmit() and call the backpressure mechanism in
xskq_prod_reserve(xs->pool->cq). As this is a shared resource in this
specific scenario, a race might occur since the rings are
single-producer single-consumer.

Fix this by moving the tx_completion_lock from the socket to the pool
as the pool is shared between the sockets that share the completion
ring. (The pool is not shared when this is not the case.) And then
protect the accesses to xskq_prod_reserve() with this lock. The
tx_completion_lock is renamed cq_lock to better reflect that it
protects accesses to the potentially shared completion ring.

Fixes: 35fcde7f8deb ("xsk: support for Tx")
Reported-by: Xuan Zhuo <xuanzhuo@linux.alibaba.com>
Signed-off-by: Magnus Karlsson <magnus.karlsson@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Björn Töpel <bjorn.topel@intel.com>
Link: https://lore.kernel.org/bpf/20201218134525.13119-2-magnus.karlsson@gmail.com
xsk: Fix memory leak for failed bind 2020-12-17T21:48:55+00:00 Magnus Karlsson magnus.karlsson@intel.com 2020-12-14T08:51:27+00:00 8bee683384087a6275c9183a483435225f7bb209 Fix a possible memory leak when a bind of an AF_XDP socket fails. When the fill and completion rings are created, they are tied to the socket. But when the buffer pool is later created at bind time, the ownership of these two rings are transferred to the buffer pool as they might be shared between sockets (and the buffer pool cannot be created until we know what we are binding to). So, before the buffer pool is created, these two rings are cleaned up with the socket, and after they have been transferred they are cleaned up together with the buffer pool. The problem is that ownership was transferred before it was absolutely certain that the buffer pool could be created and initialized correctly and when one of these errors occurred, the fill and completion rings did neither belong to the socket nor the pool and where therefore leaked. Solve this by moving the ownership transfer to the point where the buffer pool has been completely set up and there is no way it can fail. Fixes: 7361f9c3d719 ("xsk: Move fill and completion rings to buffer pool") Reported-by: syzbot+cfa88ddd0655afa88763@syzkaller.appspotmail.com Signed-off-by: Magnus Karlsson <magnus.karlsson@intel.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Björn Töpel <bjorn.topel@intel.com> Link: https://lore.kernel.org/bpf/20201214085127.3960-1-magnus.karlsson@gmail.com 
Fix a possible memory leak when a bind of an AF_XDP socket fails. When
the fill and completion rings are created, they are tied to the
socket. But when the buffer pool is later created at bind time, the
ownership of these two rings are transferred to the buffer pool as
they might be shared between sockets (and the buffer pool cannot be
created until we know what we are binding to). So, before the buffer
pool is created, these two rings are cleaned up with the socket, and
after they have been transferred they are cleaned up together with
the buffer pool.

The problem is that ownership was transferred before it was absolutely
certain that the buffer pool could be created and initialized
correctly and when one of these errors occurred, the fill and
completion rings did neither belong to the socket nor the pool and
where therefore leaked. Solve this by moving the ownership transfer
to the point where the buffer pool has been completely set up and
there is no way it can fail.

Fixes: 7361f9c3d719 ("xsk: Move fill and completion rings to buffer pool")
Reported-by: syzbot+cfa88ddd0655afa88763@syzkaller.appspotmail.com
Signed-off-by: Magnus Karlsson <magnus.karlsson@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Björn Töpel <bjorn.topel@intel.com>
Link: https://lore.kernel.org/bpf/20201214085127.3960-1-magnus.karlsson@gmail.com
Merge https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next 2020-12-14T23:34:36+00:00 Jakub Kicinski kuba@kernel.org 2020-12-14T23:34:35+00:00 a6b5e026e6238cbdd51e3c9b77cc3c79a7c24a9a Daniel Borkmann says: ==================== pull-request: bpf-next 2020-12-14 1) Expose bpf_sk_storage_*() helpers to iterator programs, from Florent Revest. 2) Add AF_XDP selftests based on veth devs to BPF selftests, from Weqaar Janjua. 3) Support for finding BTF based kernel attach targets through libbpf's bpf_program__set_attach_target() API, from Andrii Nakryiko. 4) Permit pointers on stack for helper calls in the verifier, from Yonghong Song. 5) Fix overflows in hash map elem size after rlimit removal, from Eric Dumazet. 6) Get rid of direct invocation of llc in BPF selftests, from Andrew Delgadillo. 7) Fix xsk_recvmsg() to reorder socket state check before access, from Björn Töpel. 8) Add new libbpf API helper to retrieve ring buffer epoll fd, from Brendan Jackman. 9) Batch of minor BPF selftest improvements all over the place, from Florian Lehner, KP Singh, Jiri Olsa and various others. * https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (31 commits) selftests/bpf: Add a test for ptr_to_map_value on stack for helper access bpf: Permits pointers on stack for helper calls libbpf: Expose libbpf ring_buffer epoll_fd selftests/bpf: Add set_attach_target() API selftest for module target libbpf: Support modules in bpf_program__set_attach_target() API selftests/bpf: Silence ima_setup.sh when not running in verbose mode. selftests/bpf: Drop the need for LLVM's llc selftests/bpf: fix bpf_testmod.ko recompilation logic samples/bpf: Fix possible hang in xdpsock with multiple threads selftests/bpf: Make selftest compilation work on clang 11 selftests/bpf: Xsk selftests - adding xdpxceiver to .gitignore selftests/bpf: Drop tcp-{client,server}.py from Makefile selftests/bpf: Xsk selftests - Bi-directional Sockets - SKB, DRV selftests/bpf: Xsk selftests - Socket Teardown - SKB, DRV selftests/bpf: Xsk selftests - DRV POLL, NOPOLL selftests/bpf: Xsk selftests - SKB POLL, NOPOLL selftests/bpf: Xsk selftests framework bpf: Only provide bpf_sock_from_file with CONFIG_NET bpf: Return -ENOTSUPP when attaching to non-kernel BTF xsk: Validate socket state in xsk_recvmsg, prior touching socket members ... ==================== Link: https://lore.kernel.org/r/20201214214316.20642-1-daniel@iogearbox.net Signed-off-by: Jakub Kicinski <kuba@kernel.org> 
Daniel Borkmann says:

====================
pull-request: bpf-next 2020-12-14

1) Expose bpf_sk_storage_*() helpers to iterator programs, from Florent Revest.

2) Add AF_XDP selftests based on veth devs to BPF selftests, from Weqaar Janjua.

3) Support for finding BTF based kernel attach targets through libbpf's
   bpf_program__set_attach_target() API, from Andrii Nakryiko.

4) Permit pointers on stack for helper calls in the verifier, from Yonghong Song.

5) Fix overflows in hash map elem size after rlimit removal, from Eric Dumazet.

6) Get rid of direct invocation of llc in BPF selftests, from Andrew Delgadillo.

7) Fix xsk_recvmsg() to reorder socket state check before access, from Björn Töpel.

8) Add new libbpf API helper to retrieve ring buffer epoll fd, from Brendan Jackman.

9) Batch of minor BPF selftest improvements all over the place, from Florian Lehner,
   KP Singh, Jiri Olsa and various others.

* https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (31 commits)
  selftests/bpf: Add a test for ptr_to_map_value on stack for helper access
  bpf: Permits pointers on stack for helper calls
  libbpf: Expose libbpf ring_buffer epoll_fd
  selftests/bpf: Add set_attach_target() API selftest for module target
  libbpf: Support modules in bpf_program__set_attach_target() API
  selftests/bpf: Silence ima_setup.sh when not running in verbose mode.
  selftests/bpf: Drop the need for LLVM's llc
  selftests/bpf: fix bpf_testmod.ko recompilation logic
  samples/bpf: Fix possible hang in xdpsock with multiple threads
  selftests/bpf: Make selftest compilation work on clang 11
  selftests/bpf: Xsk selftests - adding xdpxceiver to .gitignore
  selftests/bpf: Drop tcp-{client,server}.py from Makefile
  selftests/bpf: Xsk selftests - Bi-directional Sockets - SKB, DRV
  selftests/bpf: Xsk selftests - Socket Teardown - SKB, DRV
  selftests/bpf: Xsk selftests - DRV POLL, NOPOLL
  selftests/bpf: Xsk selftests - SKB POLL, NOPOLL
  selftests/bpf: Xsk selftests framework
  bpf: Only provide bpf_sock_from_file with CONFIG_NET
  bpf: Return -ENOTSUPP when attaching to non-kernel BTF
  xsk: Validate socket state in xsk_recvmsg, prior touching socket members
  ...
====================

Link: https://lore.kernel.org/r/20201214214316.20642-1-daniel@iogearbox.net
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2020-12-12T06:29:38+00:00 Jakub Kicinski kuba@kernel.org 2020-12-12T04:12:36+00:00 46d5e62dd3c34770f3bfd0642daa9a7772a00362 xdp_return_frame_bulk() needs to pass a xdp_buff to __xdp_return(). strlcpy got converted to strscpy but here it makes no functional difference, so just keep the right code. Conflicts: net/netfilter/nf_tables_api.c Signed-off-by: Jakub Kicinski <kuba@kernel.org> 
xdp_return_frame_bulk() needs to pass a xdp_buff
to __xdp_return().

strlcpy got converted to strscpy but here it makes no
functional difference, so just keep the right code.

Conflicts:
	net/netfilter/nf_tables_api.c

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
xsk: Validate socket state in xsk_recvmsg, prior touching socket members 2020-12-08T16:11:58+00:00 Björn Töpel bjorn.topel@intel.com 2020-12-07T08:20:08+00:00 3546b9b8eced9799b35ef953f766a0973b17fda2 In AF_XDP the socket state needs to be checked, prior touching the members of the socket. This was not the case for the recvmsg implementation. Fix that by moving the xsk_is_bound() call. Fixes: 45a86681844e ("xsk: Add support for recvmsg()") Reported-by: kernel test robot <oliver.sang@intel.com> Signed-off-by: Björn Töpel <bjorn.topel@intel.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Magnus Karlsson <magnus.karlsson@intel.com> Link: https://lore.kernel.org/bpf/20201207082008.132263-1-bjorn.topel@gmail.com 
In AF_XDP the socket state needs to be checked, prior touching the
members of the socket. This was not the case for the recvmsg
implementation. Fix that by moving the xsk_is_bound() call.

Fixes: 45a86681844e ("xsk: Add support for recvmsg()")
Reported-by: kernel test robot <oliver.sang@intel.com>
Signed-off-by: Björn Töpel <bjorn.topel@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Magnus Karlsson <magnus.karlsson@intel.com>
Link: https://lore.kernel.org/bpf/20201207082008.132263-1-bjorn.topel@gmail.com
xsk: Return error code if force_zc is set 2020-12-04T15:48:31+00:00 Zhang Changzhong zhangchangzhong@huawei.com 2020-12-04T10:21:16+00:00 12c8a8ca117f3d734babc3fba131fdaa329d2163 If force_zc is set, we should exit out with an error, not fall back to copy mode. Fixes: 921b68692abb ("xsk: Enable sharing of dma mappings") Reported-by: Hulk Robot <hulkci@huawei.com> Signed-off-by: Zhang Changzhong <zhangchangzhong@huawei.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Magnus Karlsson <magnus.karlsson@intel.com> Link: https://lore.kernel.org/bpf/1607077277-41995-1-git-send-email-zhangchangzhong@huawei.com 
If force_zc is set, we should exit out with an error, not fall back to
copy mode.

Fixes: 921b68692abb ("xsk: Enable sharing of dma mappings")
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Zhang Changzhong <zhangchangzhong@huawei.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Magnus Karlsson <magnus.karlsson@intel.com>
Link: https://lore.kernel.org/bpf/1607077277-41995-1-git-send-email-zhangchangzhong@huawei.com