vmxnet3 is currently at version 4 and this patch initiates the
preparation to accommodate changes for upto version 6. Introduced
utility macros for vmxnet3 version 6 comparison and update Copyright
information.
Signed-off-by: Ronak Doshi <doshir@vmware.com>
Acked-by: Guolin Yang <gyang@vmware.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Currently, when userspace reads a datagram with a buffer that is
smaller than this datagram, the data will be truncated and only
part of it can be received by users. It doesn't seem right that
users don't know the datagram size and have to use a huge buffer
to read it to avoid the truncation.
This patch to fix it by keeping the skb in rcv queue until the
whole data is read by users. Only the last msg of the datagram
will be marked with MSG_EOR, just as TCP/SCTP does.
Note that this will work as above only when MSG_EOR is set in the
flags parameter of recvmsg(), so that it won't break any old user
applications.
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Acked-by: Jon Maloy <jmaloy@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
nguy/next-queue
Tony Nguyen says:
====================
1GbE Intel Wired LAN Driver Updates 2021-07-16
Vinicius Costa Gomes says:
Add support for steering traffic to specific RX queues using Flex Filters.
As the name implies, Flex Filters are more flexible than using
Layer-2, VLAN or MAC address filters, one of the reasons is that they
allow "AND" operations more easily, e.g. when the user wants to steer
some traffic based on the source MAC address and the packet ethertype.
Future work include adding support for offloading tc-u32 filters to
the hardware.
The series is divided as follows:
Patch 1/5, add the low level primitives for configuring Flex filters.
Patch 2/5 and 3/5, allow ethtool to manage Flex filters.
Patch 4/5, when specifying filters that have multiple predicates, use
Flex filters.
Patch 5/5, Adds support for exposing the i225 LEDs using the LED subsystem.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Each i225 has three LEDs. Export them via the LED class framework.
Each LED is controllable via sysfs. Example:
$ cd /sys/class/leds/igc_led0
$ cat brightness # Current Mode
$ cat max_brightness # 15
$ echo 0 > brightness # Mode 0
$ echo 1 > brightness # Mode 1
The brightness field here reflects the different LED modes ranging
from 0 to 15.
Signed-off-by: Kurt Kanzenbach <kurt@linutronix.de>
Reviewed-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Tested-by: Dvora Fuxbrumer <dvorax.fuxbrumer@linux.intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>
Currently flex filters are only used for filters containing user data.
However, it makes sense to utilize them also for filters having
multiple conditions, because that's not supported by the driver at the
moment. Add it.
Signed-off-by: Kurt Kanzenbach <kurt@linutronix.de>
Reviewed-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Vinicius Costa Gomes <vinicius.gomes@intel.com>
Tested-by: Dvora Fuxbrumer <dvorax.fuxbrumer@linux.intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>
Allows Flex Filters to be installed.
The previous restriction to the types of filters that can be installed
can now be lifted.
Signed-off-by: Vinicius Costa Gomes <vinicius.gomes@intel.com>
Tested-by: Dvora Fuxbrumer <dvorax.fuxbrumer@linux.intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>
Use the flex filter mechanism to extend the current ethtool filter
operations by intercoperating the user data. This allows to match
eight more bytes within a Ethernet frame in addition to macs, ether
types and vlan.
The matching pattern looks like this:
* dest_mac [6]
* src_mac [6]
* tpid [2]
* vlan tci [2]
* ether type [2]
* user data [8]
This can be used to match Profinet traffic classes by FrameID range.
Signed-off-by: Kurt Kanzenbach <kurt@linutronix.de>
Reviewed-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Tested-by: Dvora Fuxbrumer <dvorax.fuxbrumer@linux.intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>
The Intel i225 NIC has the possibility to add flex filters which can
match up to the first 128 byte of a packet. These filters are useful
for all kind of packet matching. One particular use case is Profinet,
as the different traffic classes are distinguished by the frame id
range which cannot be matched by any other means.
Add code to configure and enable flex filters.
Signed-off-by: Kurt Kanzenbach <kurt@linutronix.de>
Reviewed-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Vinicius Costa Gomes <vinicius.gomes@intel.com>
Tested-by: Dvora Fuxbrumer <dvorax.fuxbrumer@linux.intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>
Implement Wake-on-LAN feature for 88X3310 and 88E2110.
This is done by enabling WoL interrupt and WoL detection and
configuring MAC address into WoL magic packet registers
Signed-off-by: Voon Weifeng <weifeng.voon@intel.com>
Signed-off-by: Ling Pei Lee <pei.lee.ling@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Remove un-used "phy-reset-delay" property which found when do dtbs_check
(set additionalProperties: false in fsl,fec.yaml).
Double check current driver and commit history, "phy-reset-delay" never comes
up, so it should be safe to remove it.
$ make ARCH=arm CROSS_COMPILE=arm-linux-gnueabihf- dtbs_check DT_SCHEMA_FILES=Documentation/devicetree/bindings/net/fsl,fec.yaml
arch/arm/boot/dts/imx7d-mba7.dt.yaml: ethernet@30be0000: 'phy-reset-delay' does not match any of the regexes: 'pinctrl-[0-9]+'
arch/arm/boot/dts/imx7d-mba7.dt.yaml: ethernet@30bf0000: 'phy-reset-delay' does not match any of the regexes: 'pinctrl-[0-9]+'
/arch/arm/boot/dts/imx7s-mba7.dt.yaml: ethernet@30be0000: 'phy-reset-delay' does not match any of the regexes: 'pinctrl-[0-9]+'
Signed-off-by: Joakim Zhang <qiangqing.zhang@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Correct node name for FEC which found when do dtbs_check.
$ make ARCH=arm CROSS_COMPILE=arm-linux-gnueabihf- dtbs_check DT_SCHEMA_FILES=Documentation/devicetree/bindings/net/fsl,fec.yaml
arch/arm/boot/dts/imx35-eukrea-mbimxsd35-baseboard.dt.yaml: fec@50038000: $nodename:0: 'fec@50038000' does not match '^ethernet(@.*)?$'
arch/arm/boot/dts/imx35-pdk.dt.yaml: fec@50038000: $nodename:0: 'fec@50038000' does not match '^ethernet(@.*)?$'
Signed-off-by: Joakim Zhang <qiangqing.zhang@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
In order to automate the verification of DT nodes convert fsl-fec.txt to
fsl,fec.yaml, and pass binding check with below command.
$ make ARCH=arm CROSS_COMPILE=arm-linux-gnueabihf- dt_binding_check DT_SCHEMA_FILES=Documentation/devicetree/bindings/net/fsl,fec.yaml
DTEX Documentation/devicetree/bindings/net/fsl,fec.example.dts
DTC Documentation/devicetree/bindings/net/fsl,fec.example.dt.yaml
CHECK Documentation/devicetree/bindings/net/fsl,fec.example.dt.yaml
Signed-off-by: Joakim Zhang <qiangqing.zhang@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Currently netdevsim only supports a single queue per port, which is
insufficient for testing multi-queue TC schedulers e.g. sch_mq. Extend
the current sysfs interface so that users can create ports with multiple
queues:
$ echo "[ID] [PORT_COUNT] [NUM_QUEUES]" > /sys/bus/netdevsim/new_device
As an example, echoing "2 4 8" creates 4 ports, with 8 queues per port.
Note, this is compatible with the current interface, with default number
of queues set to 1. For example, echoing "2 4" creates 4 ports with 1
queue per port; echoing "2" simply creates 1 port with 1 queue.
Reviewed-by: Cong Wang <cong.wang@bytedance.com>
Signed-off-by: Peilin Ye <peilin.ye@bytedance.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The Open vSwitch kernel module uses the upcall mechanism to send
packets from kernel space to user space when it misses in the kernel
space flow table. The upcall sends packets via a Netlink socket.
Currently, a Netlink socket is created for every vport. In this way,
there is a 1:1 mapping between a vport and a Netlink socket.
When a packet is received by a vport, if it needs to be sent to
user space, it is sent via the corresponding Netlink socket.
This mechanism, with various iterations of the corresponding user
space code, has seen some limitations and issues:
* On systems with a large number of vports, there is a correspondingly
large number of Netlink sockets which can limit scaling.
(https://bugzilla.redhat.com/show_bug.cgi?id=1526306)
* Packet reordering on upcalls.
(https://bugzilla.redhat.com/show_bug.cgi?id=1844576)
* A thundering herd issue.
(https://bugzilla.redhat.com/show_bug.cgi?id=1834444)
This patch introduces an alternative, feature-negotiated, upcall
mode using a per-cpu dispatch rather than a per-vport dispatch.
In this mode, the Netlink socket to be used for the upcall is
selected based on the CPU of the thread that is executing the upcall.
In this way, it resolves the issues above as:
a) The number of Netlink sockets scales with the number of CPUs
rather than the number of vports.
b) Ordering per-flow is maintained as packets are distributed to
CPUs based on mechanisms such as RSS and flows are distributed
to a single user space thread.
c) Packets from a flow can only wake up one user space thread.
The corresponding user space code can be found at:
https://mail.openvswitch.org/pipermail/ovs-dev/2021-July/385139.html
Bugzilla: https://bugzilla.redhat.com/1844576
Signed-off-by: Mark Gray <mark.d.gray@redhat.com>
Acked-by: Flavio Leitner <fbl@sysclose.org>
Acked-by: Pravin B Shelar <pshelar@ovn.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Fix the clang build warning:
drivers/net/ethernet/broadcom/bnx2x/bnx2x_sriov.c:1862:13: error: variable 'cur_data_offset' set but not used [-Werror,-Wunused-but-set-variable]
dma_addr_t cur_data_offset;
Signed-off-by: Bill Wendling <morbo@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Use 'bitmap_alloc()/bitmap_free()' instead of hand-writing it.
This makes the code less verbose.
Also, use 'bitmap_alloc()' instead of 'bitmap_zalloc()' because the bitmap
is fully overridden by a 'bitmap_copy()' call just after its allocation.
While at it, remove an extra and unneeded space.
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
It has been deal with the 'if (err' statement in rtnetlink_send()
and rtnl_unicast(). so remove unnecessary if statement.
v2: use the raw name rtnetlink_send().
Signed-off-by: Yajun Deng <yajun.deng@linux.dev>
Signed-off-by: David S. Miller <davem@davemloft.net>
The netlink_{broadcast, unicast} don't deal with 'if (err > 0' statement
but nlmsg_{multicast, unicast} do. The nlmsg_notify() contains them.
so use nlmsg_notify() instead. so that the caller wouldn't deal with
'if (err > 0' statement.
v2: use nlmsg_notify() will do well.
Signed-off-by: Yajun Deng <yajun.deng@linux.dev>
Signed-off-by: David S. Miller <davem@davemloft.net>
The 'tail' pointer is also free-running count, so it needs to be masked
as 'adminq_prod_cnt' does, to become an index value of AdminQ buffer.
Fixes: 5cdad90de6 ("gve: Batch AQ commands for creating and destroying queues.")
Signed-off-by: Haiyue Wang <haiyue.wang@intel.com>
Reviewed-by: Catherine Sullivan <csully@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Alexei Starovoitov says:
====================
pull-request: bpf-next 2021-07-15
The following pull-request contains BPF updates for your *net-next* tree.
We've added 45 non-merge commits during the last 15 day(s) which contain
a total of 52 files changed, 3122 insertions(+), 384 deletions(-).
The main changes are:
1) Introduce bpf timers, from Alexei.
2) Add sockmap support for unix datagram socket, from Cong.
3) Fix potential memleak and UAF in the verifier, from He.
4) Add bpf_get_func_ip helper, from Jiri.
5) Improvements to generic XDP mode, from Kumar.
6) Support for passing xdp_md to XDP programs in bpf_prog_run, from Zvi.
===================
Signed-off-by: David S. Miller <davem@davemloft.net>
Cong Wang says:
====================
From: Cong Wang <cong.wang@bytedance.com>
This is the last patchset of the original large patchset. In the
previous patchset, a new BPF sockmap program BPF_SK_SKB_VERDICT
was introduced and UDP began to support it too. In this patchset,
we add BPF_SK_SKB_VERDICT support to Unix datagram socket, so that
we can finally splice Unix datagram socket and UDP socket. Please
check each patch description for more details.
To see the big picture, the previous patchsets are available here:
https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next.git/commit/?id=1e0ab70778bd86a90de438cc5e1535c115a7c396https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next.git/commit/?id=89d69c5d0fbcabd8656459bc8b1a476d6f1efee4
and this patchset is available here:
https://github.com/congwang/linux/tree/sockmap3
Acked-by: John Fastabend <john.fastabend@gmail.com>
---
v5: lift socket state check for dgram
remove ->unhash() case
add retries for EAGAIN in all test cases
remove an unused parameter of __unix_dgram_recvmsg()
rebase on the latest bpf-next
v4: fix af_unix disconnect case
add unix_unhash()
split out two small patches
reduce u->iolock critical section
remove an unused parameter of __unix_dgram_recvmsg()
v3: fix Kconfig dependency
make unix_read_sock() static
fix a UAF in unix_release()
add a missing header unix_bpf.c
v2: separate out from the original large patchset
rebase to the latest bpf-next
clean up unix_read_sock()
export sock_map_close()
factor out some helpers in selftests for code reuse
====================
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
We have to implement unix_dgram_bpf_recvmsg() to replace the
original ->recvmsg() to retrieve skmsg from ingress_msg.
AF_UNIX is again special here because the lack of
sk_prot->recvmsg(). I simply add a special case inside
unix_dgram_recvmsg() to call sk->sk_prot->recvmsg() directly.
Signed-off-by: Cong Wang <cong.wang@bytedance.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20210704190252.11866-8-xiyou.wangcong@gmail.com
Unlike af_inet, unix_proto is very different, it does not even
have a ->close(). We have to add a dummy implementation to
satisfy sockmap. Normally it is just a nop, it is introduced only
for sockmap to replace it.
Signed-off-by: Cong Wang <cong.wang@bytedance.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20210704190252.11866-6-xiyou.wangcong@gmail.com
Currently only unix stream socket sets TCP_ESTABLISHED,
datagram socket can set this too when they connect to its
peer socket. At least __ip4_datagram_connect() does the same.
This will be used to determine whether an AF_UNIX datagram
socket can be redirected to in sockmap.
Signed-off-by: Cong Wang <cong.wang@bytedance.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20210704190252.11866-5-xiyou.wangcong@gmail.com
TCP and other connection oriented sockets have accept()
for each incoming connection on the server side, hence
they can just insert those fd's from accept() to sockmap,
which are of course established.
Now with datagram sockets begin to support sockmap and
redirection, the restriction is no longer applicable to
them, as they have no accept(). So we have to lift this
restriction for them. This is fine, because inside
bpf_sk_redirect_map() we still have another socket status
check, sock_map_redirect_allowed(), as a guard.
This also means they do not have to be removed from
sockmap when disconnecting.
Signed-off-by: Cong Wang <cong.wang@bytedance.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20210704190252.11866-3-xiyou.wangcong@gmail.com
Currently sock_map still has Kconfig dependency on CONFIG_INET,
but there is no actual functional dependency on it after we
introduce ->psock_update_sk_prot().
We have to extend it to CONFIG_NET now as we are going to
support AF_UNIX.
Signed-off-by: Cong Wang <cong.wang@bytedance.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20210704190252.11866-2-xiyou.wangcong@gmail.com
Jiri Olsa says:
====================
Add bpf_get_func_ip helper that returns IP address of the
caller function for trampoline and krobe programs.
There're 2 specific implementation of the bpf_get_func_ip
helper, one for trampoline progs and one for kprobe/kretprobe
progs.
The trampoline helper call is replaced/inlined by the verifier
with simple move instruction. The kprobe/kretprobe is actual
helper call that returns prepared caller address.
Also available at:
https://git.kernel.org/pub/scm/linux/kernel/git/jolsa/perf.git
bpf/get_func_ip
v4 changes:
- dropped jit/x86 check for get_func_ip tracing check [Alexei]
- added code to bpf_get_func_ip_tracing [Alexei]
and tested that it works without inlining [Alexei]
- changed has_get_func_ip to check_get_func_ip [Andrii]
- replaced test assert loop with explicit asserts [Andrii]
- adde bpf_program__attach_kprobe_opts function
and use it for offset setup [Andrii]
- used bpf_program__set_autoload(false) for test6 [Andrii]
- added Masami's ack
v3 changes:
- resend with Masami in cc and v3 in each patch subject
v2 changes:
- use kprobe_running to get kprobe instead of cpu var [Masami]
- added support to add kprobe on function+offset
and test for that [Alan]
====================
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Adding test for bpf_get_func_ip in kprobe+ofset probe.
Because of the offset value it's arch specific, enabling
the new test only for x86_64 architecture.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20210714094400.396467-9-jolsa@kernel.org
kprobes can be placed on most instructions in a function, not
just entry, and ftrace and bpftrace support the function+offset
notification for probe placement. Adding parsing of func_name
into func+offset to bpf_program__attach_kprobe() allows the
user to specify
SEC("kprobe/bpf_fentry_test5+0x6")
...for example, and the offset can be passed to perf_event_open_probe()
to support kprobe attachment.
Signed-off-by: Alan Maguire <alan.maguire@oracle.com>
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20210714094400.396467-8-jolsa@kernel.org
Adding bpf_program__attach_kprobe_opts that does the same
as bpf_program__attach_kprobe, but takes opts argument.
Currently opts struct holds just retprobe bool, but we will
add new field in following patch.
The function is not exported, so there's no need to add
size to the struct bpf_program_attach_kprobe_opts for now.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20210714094400.396467-7-jolsa@kernel.org
Adding bpf_get_func_ip helper for BPF_PROG_TYPE_KPROBE programs,
so it's now possible to call bpf_get_func_ip from both kprobe and
kretprobe programs.
Taking the caller's address from 'struct kprobe::addr', which is
defined for both kprobe and kretprobe.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org>
Link: https://lore.kernel.org/bpf/20210714094400.396467-5-jolsa@kernel.org
Adding bpf_get_func_ip helper for BPF_PROG_TYPE_TRACING programs,
specifically for all trampoline attach types.
The trampoline's caller IP address is stored in (ctx - 8) address.
so there's no reason to actually call the helper, but rather fixup
the call instruction and return [ctx - 8] value directly.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20210714094400.396467-4-jolsa@kernel.org
Enabling BPF_TRAMP_F_IP_ARG for trampolines that actually need it.
The BPF_TRAMP_F_IP_ARG adds extra 3 instructions to trampoline code
and is used only by programs with bpf_get_func_ip helper, which is
added in following patch and sets call_get_func_ip bit.
This patch ensures that BPF_TRAMP_F_IP_ARG flag is used only for
trampolines that have programs with call_get_func_ip set.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20210714094400.396467-3-jolsa@kernel.org
Storing caller's ip in trampoline's stack. Trampoline programs
can reach the IP in (ctx - 8) address, so there's no change in
program's arguments interface.
The IP address is takes from [fp + 8], which is return address
from the initial 'call fentry' call to trampoline.
This IP address will be returned via bpf_get_func_ip helper
helper, which is added in following patches.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20210714094400.396467-2-jolsa@kernel.org
Alexei Starovoitov says:
====================
The first request to support timers in bpf was made in 2013 before sys_bpf
syscall was added. That use case was periodic sampling. It was address with
attaching bpf programs to perf_events. Then during XDP development the timers
were requested to do garbage collection and health checks. They were worked
around by implementing timers in user space and triggering progs with
BPF_PROG_RUN command. The user space timers and perf_event+bpf timers are not
armed by the bpf program. They're done asynchronously vs program execution.
The XDP program cannot send a packet and arm the timer at the same time. The
tracing prog cannot record an event and arm the timer right away. This large
class of use cases remained unaddressed. The jiffy based and hrtimer based
timers are essential part of the kernel development and with this patch set
the hrtimer based timers will be available to bpf programs.
TLDR: bpf timers is a wrapper of hrtimers with all the extra safety added
to make sure bpf progs cannot crash the kernel.
v6->v7:
- address Andrii's comments and add his Acks.
v5->v6:
- address code review feedback from Martin and add his Acks.
- add usercnt > 0 check to bpf_timer_init and remove timers_cancel_and_free
second loop in map_free callbacks.
- add cond_resched_rcu.
v4->v5:
- Martin noticed the following issues:
. prog could be reallocated bpf_patch_insn_data().
Fixed by passing 'aux' into bpf_timer_set_callback, since 'aux' is stable
during insn patching.
. Added missing rcu_read_lock.
. Removed redundant record_map.
- Discovered few bugs with stress testing:
. One cpu does htab_free_prealloced_timers->bpf_timer_cancel_and_free->hrtimer_cancel
while another is trying to do something with the timer like bpf_timer_start/set_callback.
Those ops try to acquire bpf_spin_lock that is already taken by bpf_timer_cancel_and_free,
so both cpus spin forever. The same problem existed in bpf_timer_cancel().
One bpf prog on one cpu might call bpf_timer_cancel and wait, while another cpu is in
the timer callback that tries to do bpf_timer_*() helper on the same timer.
The fix is to do drop_prog_refcnt() and unlock. And only then hrtimer_cancel.
Because of this had to add callback_fn != NULL check to bpf_timer_cb().
Also removed redundant bpf_prog_inc/put from bpf_timer_cb() and replaced
with rcu_dereference_check similar to recent rcu_read_lock-removal from drivers.
bpf_timer_cb is in softirq.
. Managed to hit refcnt==0 while doing bpf_prog_put from bpf_timer_cancel_and_free().
That exposed the issue that bpf_prog_put wasn't ready to be called from irq context.
Fixed similar to bpf_map_put which is irq ready.
- Refactored BPF_CALL_1(bpf_spin_lock) into __bpf_spin_lock_irqsave() to
make the main logic more clear, since Martin and Yonghong brought up this concern.
v3->v4:
1.
Split callback_fn from bpf_timer_start into bpf_timer_set_callback as
suggested by Martin. That makes bpf timer api match one to one to
kernel hrtimer api and provides greater flexibility.
2.
Martin also discovered the following issue with uref approach:
bpftool prog load xdp_timer.o /sys/fs/bpf/xdp_timer type xdp
bpftool net attach xdpgeneric pinned /sys/fs/bpf/xdp_timer dev lo
rm /sys/fs/bpf/xdp_timer
nc -6 ::1 8888
bpftool net detach xdpgeneric dev lo
The timer callback stays active in the kernel though the prog was detached
and map usercnt == 0.
It happened because 'bpftool prog load' pinned the prog only.
The map usercnt went to zero. Subsequent attach and runs didn't
affect map usercnt. The timer was able to start and bpf_prog_inc itself.
When the prog was detached the prog stayed active.
To address this issue added
if (!atomic64_read(&(t->map->usercnt))) return -EPERM;
to the first patch.
Which means that timers are allowed only in the maps that are held
by user space with open file descriptor or maps pinned in bpffs.
3.
Discovered that timers in inner maps were broken.
The inner map pointers are dynamic. Therefore changed bpf_timer_init()
to accept explicit map pointer supplied by the program instead
of hidden map pointer supplied by the verifier.
To make sure that pointer to a timer actually belongs to that map
added the verifier check in patch 3.
4.
Addressed Yonghong's feedback. Improved comments and added
dynamic in_nmi() check.
Added Acks.
v2->v3:
The v2 approach attempted to bump bpf_prog refcnt when bpf_timer_start is
called to make sure callback code doesn't disappear when timer is active and
drop refcnt when timer cb is done. That led to a ton of race conditions between
callback running and concurrent bpf_timer_init/start/cancel on another cpu,
and concurrent bpf_map_update/delete_elem, and map destroy.
Then v2.5 approach skipped prog refcnt altogether. Instead it remembered all
timers that bpf prog armed in a link list and canceled them when prog refcnt
went to zero. The race conditions disappeared, but timers in map-in-map could
not be supported cleanly, since timers in inner maps have inner map's life time
and don't match prog's life time.
This v3 approach makes timers to be owned by maps. It allows timers in inner
maps to be supported from the start. This apporach relies on "user refcnt"
scheme used in prog_array that stores bpf programs for bpf_tail_call. The
bpf_timer_start() increments prog refcnt, but unlike 1st approach the timer
callback does decrement the refcnt. The ops->map_release_uref is
responsible for cancelling the timers and dropping prog refcnt when user space
reference to a map is dropped. That addressed all the races and simplified
locking.
Andrii presented a use case where specifying callback_fn in bpf_timer_init()
is inconvenient vs specifying in bpf_timer_start(). The bpf_timer_init()
typically is called outside for timer callback, while bpf_timer_start() most
likely will be called from the callback.
timer_cb() { ... bpf_timer_start(timer_cb); ...} looks like recursion and as
infinite loop to the verifier. The verifier had to be made smarter to recognize
such async callbacks. Patches 7,8,9 addressed that.
Patch 1 and 2 refactoring.
Patch 3 implements bpf timer helpers and locking.
Patch 4 implements map side of bpf timer support.
Patch 5 prevent pointer mismatch in bpf_timer_init.
Patch 6 adds support for BTF in inner maps.
Patch 7 teaches check_cfg() pass to understand async callbacks.
Patch 8 teaches do_check() pass to understand async callbacks.
Patch 9 teaches check_max_stack_depth() pass to understand async callbacks.
Patches 10 and 11 are the tests.
v1->v2:
- Addressed great feedback from Andrii and Toke.
- Fixed race between parallel bpf_timer_*() ops.
- Fixed deadlock between timer callback and LRU eviction or bpf_map_delete/update.
- Disallowed mmap and global timers.
- Allow spin_lock and bpf_timer in an element.
- Fixed memory leaks due to map destruction and LRU eviction.
- A ton more tests.
====================
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Check that map-in-map supports bpf timers.
Check that indirect "recursion" of timer callbacks works:
timer_cb1() { bpf_timer_set_callback(timer_cb2); }
timer_cb2() { bpf_timer_set_callback(timer_cb1); }
Check that
bpf_map_release
htab_free_prealloced_timers
bpf_timer_cancel_and_free
hrtimer_cancel
works while timer cb is running.
"while true; do ./test_progs -t timer_mim; done"
is a great stress test. It caught missing timer cancel in htab->extra_elems.
timer_mim_reject.c is a negative test that checks
that timer<->map mismatch is prevented.
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Toke Høiland-Jørgensen <toke@redhat.com>
Link: https://lore.kernel.org/bpf/20210715005417.78572-12-alexei.starovoitov@gmail.com
Add bpf_timer test that creates timers in preallocated and
non-preallocated hash, in array and in lru maps.
Let array timer expire once and then re-arm it for 35 seconds.
Arm lru timer into the same callback.
Then arm and re-arm hash timers 10 times each.
At the last invocation of prealloc hash timer cancel the array timer.
Force timer free via LRU eviction and direct bpf_map_delete_elem.
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Toke Høiland-Jørgensen <toke@redhat.com>
Link: https://lore.kernel.org/bpf/20210715005417.78572-11-alexei.starovoitov@gmail.com
Teach max stack depth checking algorithm about async callbacks
that don't increase bpf program stack size.
Also add sanity check that bpf_tail_call didn't sneak into async cb.
It's impossible, since PTR_TO_CTX is not available in async cb,
hence the program cannot contain bpf_tail_call(ctx,...);
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Toke Høiland-Jørgensen <toke@redhat.com>
Link: https://lore.kernel.org/bpf/20210715005417.78572-10-alexei.starovoitov@gmail.com
bpf_for_each_map_elem() and bpf_timer_set_callback() helpers are relying on
PTR_TO_FUNC infra in the verifier to validate addresses to subprograms
and pass them into the helpers as function callbacks.
In case of bpf_for_each_map_elem() the callback is invoked synchronously
and the verifier treats it as a normal subprogram call by adding another
bpf_func_state and new frame in __check_func_call().
bpf_timer_set_callback() doesn't invoke the callback directly.
The subprogram will be called asynchronously from bpf_timer_cb().
Teach the verifier to validate such async callbacks as special kind
of jump by pushing verifier state into stack and let pop_stack() process it.
Special care needs to be taken during state pruning.
The call insn doing bpf_timer_set_callback has to be a prune_point.
Otherwise short timer callbacks might not have prune points in front of
bpf_timer_set_callback() which means is_state_visited() will be called
after this call insn is processed in __check_func_call(). Which means that
another async_cb state will be pushed to be walked later and the verifier
will eventually hit BPF_COMPLEXITY_LIMIT_JMP_SEQ limit.
Since push_async_cb() looks like another push_stack() branch the
infinite loop detection will trigger false positive. To recognize
this case mark such states as in_async_callback_fn.
To distinguish infinite loop in async callback vs the same callback called
with different arguments for different map and timer add async_entry_cnt
to bpf_func_state.
Enforce return zero from async callbacks.
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Toke Høiland-Jørgensen <toke@redhat.com>
Link: https://lore.kernel.org/bpf/20210715005417.78572-9-alexei.starovoitov@gmail.com
In the following bpf subprogram:
static int timer_cb(void *map, void *key, void *value)
{
bpf_timer_set_callback(.., timer_cb);
}
the 'timer_cb' is a pointer to a function.
ld_imm64 insn is used to carry this pointer.
bpf_pseudo_func() returns true for such ld_imm64 insn.
Unlike bpf_for_each_map_elem() the bpf_timer_set_callback() is asynchronous.
Relax control flow check to allow such "recursion" that is seen as an infinite
loop by check_cfg(). The distinction between bpf_for_each_map_elem() the
bpf_timer_set_callback() is done in the follow up patch.
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Toke Høiland-Jørgensen <toke@redhat.com>
Link: https://lore.kernel.org/bpf/20210715005417.78572-8-alexei.starovoitov@gmail.com
BTF is required for 'struct bpf_timer' to be recognized inside map value.
The bpf timers are supported inside inner maps.
Remember 'struct btf *' in inner_map_meta to make it available
to the verifier in the sequence:
struct bpf_map *inner_map = bpf_map_lookup_elem(&outer_map, ...);
if (inner_map)
timer = bpf_map_lookup_elem(&inner_map, ...);
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Yonghong Song <yhs@fb.com>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Toke Høiland-Jørgensen <toke@redhat.com>
Link: https://lore.kernel.org/bpf/20210715005417.78572-7-alexei.starovoitov@gmail.com
bpf_timer_init() arguments are:
1. pointer to a timer (which is embedded in map element).
2. pointer to a map.
Make sure that pointer to a timer actually belongs to that map.
Use map_uid (which is unique id of inner map) to reject:
inner_map1 = bpf_map_lookup_elem(outer_map, key1)
inner_map2 = bpf_map_lookup_elem(outer_map, key2)
if (inner_map1 && inner_map2) {
timer = bpf_map_lookup_elem(inner_map1);
if (timer)
// mismatch would have been allowed
bpf_timer_init(timer, inner_map2);
}
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Toke Høiland-Jørgensen <toke@redhat.com>
Link: https://lore.kernel.org/bpf/20210715005417.78572-6-alexei.starovoitov@gmail.com
Restrict bpf timers to array, hash (both preallocated and kmalloced), and
lru map types. The per-cpu maps with timers don't make sense, since 'struct
bpf_timer' is a part of map value. bpf timers in per-cpu maps would mean that
the number of timers depends on number of possible cpus and timers would not be
accessible from all cpus. lpm map support can be added in the future.
The timers in inner maps are supported.
The bpf_map_update/delete_elem() helpers and sys_bpf commands cancel and free
bpf_timer in a given map element.
Similar to 'struct bpf_spin_lock' BTF is required and it is used to validate
that map element indeed contains 'struct bpf_timer'.
Make check_and_init_map_value() init both bpf_spin_lock and bpf_timer when
map element data is reused in preallocated htab and lru maps.
Teach copy_map_value() to support both bpf_spin_lock and bpf_timer in a single
map element. There could be one of each, but not more than one. Due to 'one
bpf_timer in one element' restriction do not support timers in global data,
since global data is a map of single element, but from bpf program side it's
seen as many global variables and restriction of single global timer would be
odd. The sys_bpf map_freeze and sys_mmap syscalls are not allowed on maps with
timers, since user space could have corrupted mmap element and crashed the
kernel. The maps with timers cannot be readonly. Due to these restrictions
search for bpf_timer in datasec BTF in case it was placed in the global data to
report clear error.
The previous patch allowed 'struct bpf_timer' as a first field in a map
element only. Relax this restriction.
Refactor lru map to s/bpf_lru_push_free/htab_lru_push_free/ to cancel and free
the timer when lru map deletes an element as a part of it eviction algorithm.
Make sure that bpf program cannot access 'struct bpf_timer' via direct load/store.
The timer operation are done through helpers only.
This is similar to 'struct bpf_spin_lock'.
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Yonghong Song <yhs@fb.com>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Toke Høiland-Jørgensen <toke@redhat.com>
Link: https://lore.kernel.org/bpf/20210715005417.78572-5-alexei.starovoitov@gmail.com
Ronak Doshi