__cgroup_bpf_attach() and __cgroup_bpf_detach() functions have
a good amount of duplicated code, which is possible to eliminate
by introducing the update_effective_progs() helper function.

The update_effective_progs() calls compute_effective_progs()
and then in case of success it calls activate_effective_progs()
for each descendant cgroup. In case of failure (OOM), it releases
allocated prog arrays and return the error code.
Signed-off-by: NRoman Gushchin <guro@fb.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: NSong Liu <songliubraving@fb.com>
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>

Add support for adjust_tail.  There are no FW changes needed but add
a FW capability just in case there would be any issue with previously
released FW, or we will have to change the ABI in the future.

The helper is trivial and shouldn't be used too often so just inline
the body of the function.  We add the delta to locally maintained
packet length register and check for overflow, since add of negative
value must overflow if result is positive.  Note that if delta of 0
would be allowed in the kernel this trick stops working and we need
one more instruction to compare lengths before and after the change.
Signed-off-by: NJakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: NQuentin Monnet <quentin.monnet@netronome.com>
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>

Commit fbeb1603 ("bpf: verifier: MOV64 don't mark dst reg unbounded")
revealed a typo in commit fb30d4b7 ("bpf: Add tests for map-in-map"):
BPF_MOV64_REG(BPF_REG_0, 0) was used instead of
BPF_MOV64_IMM(BPF_REG_0, 0).

I've noticed the problem by running bpf kselftests.

Fixes: fb30d4b7 ("bpf: Add tests for map-in-map")
Signed-off-by: NRoman Gushchin <guro@fb.com>
Cc: Martin KaFai Lau <kafai@fb.com>
Cc: Arthur Fabre <afabre@cloudflare.com>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Alexei Starovoitov <ast@kernel.org>
Acked-by: NMartin KaFai Lau <kafai@fb.com>
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>

Roman Gushchin says:

====================
This patchset implements cgroup local storage for bpf programs.
The main idea is to provide a fast accessible memory for storing
various per-cgroup data, e.g. number of transmitted packets.

Cgroup local storage looks as a special type of map for userspace,
and is accessible using generic bpf maps API for reading and
updating of the data. The (cgroup inode id, attachment type) pair
is used as a map key.

A user can't create new entries or destroy existing entries;
it happens automatically when a user attaches/detaches a bpf program
to a cgroup.

From a bpf program's point of view, cgroup storage is accessible
without lookup using the special get_local_storage() helper function.
It takes a map fd as an argument. It always returns a valid pointer
to the corresponding memory area.

To implement such a lookup-free access a pointer to the cgroup
storage is saved for an attachment of a bpf program to a cgroup,
if required by the program. Before running the program, it's saved
in a special global per-cpu variable, which is accessible from the
get_local_storage() helper.

This patchset implement only cgroup local storage, however the API
is intentionally made extensible to support other local storage types
further: e.g. thread local storage, socket local storage, etc.

v7->v6:
  - fixed a use-after-free bug, caused by not clearing
    prog->aux->cgroup_storage pointer after releasing the map

v6->v5:
  - fixed an error with returning -EINVAL instead of a pointer

v5->v4:
  - fixed an issue in verifier (test that flags == 0 properly)
  - added a corresponding test
  - added a note about synchronization, sync docs to tools/uapi/...
  - switched the cgroup test to use XADD
  - added a check for attr->max_entries to be 0, and atter->max_flags
    to be sane
  - use bpf_uncharge_memlock() in bpf_uncharge_memlock()
  - rebased to bpf-next

v4->v3:
  - fixed a leak in cgroup attachment code (discovered by Daniel)
  - cgroup storage map will be released if the corresponding
    bpf program failed to load by any reason
  - introduced bpf_uncharge_memlock() helper

v3->v2:
  - fixed more build and sparse issues
  - rebased to bpf-next

v2->v1:
  - fixed build issues
  - removed explicit rlimit calls in patch 14
  - rebased to bpf-next
====================
Signed-off-by: NRoman Gushchin <guro@fb.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>

The test_cgrp2_attach test covers bpf cgroup attachment code well,
so let's re-use it for testing allocation/releasing of cgroup storage.

The extension is pretty straightforward: the bpf program will use
the cgroup storage to save the number of transmitted bytes.

Expected output:
  $ ./test_cgrp2_attach2
  Attached DROP prog. This ping in cgroup /foo should fail...
  ping: sendmsg: Operation not permitted
  Attached DROP prog. This ping in cgroup /foo/bar should fail...
  ping: sendmsg: Operation not permitted
  Attached PASS prog. This ping in cgroup /foo/bar should pass...
  Detached PASS from /foo/bar while DROP is attached to /foo.
  This ping in cgroup /foo/bar should fail...
  ping: sendmsg: Operation not permitted
  Attached PASS from /foo/bar and detached DROP from /foo.
  This ping in cgroup /foo/bar should pass...
  ### override:PASS
  ### multi:PASS
Signed-off-by: NRoman Gushchin <guro@fb.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: NMartin KaFai Lau <kafai@fb.com>
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>

Implement a test to cover the cgroup storage functionality.
The test implements a bpf program which drops every second packet
by using the cgroup storage as a persistent storage.

The test also use the userspace API to check the data
in the cgroup storage, alter it, and check that the loaded
and attached bpf program sees the update.

Expected output:
  $ ./test_cgroup_storage
  test_cgroup_storage:PASS
Signed-off-by: NRoman Gushchin <guro@fb.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: NMartin KaFai Lau <kafai@fb.com>
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>

Add the following verifier tests to cover the cgroup storage
functionality:
1) valid access to the cgroup storage
2) invalid access: use regular hashmap instead of cgroup storage map
3) invalid access: use invalid map fd
4) invalid access: try access memory after the cgroup storage
5) invalid access: try access memory before the cgroup storage
6) invalid access: call get_local_storage() with non-zero flags

For tests 2)-6) check returned error strings.

Expected output:
  $ ./test_verifier
  #0/u add+sub+mul OK
  #0/p add+sub+mul OK
  #1/u DIV32 by 0, zero check 1 OK
  ...
  #280/p valid cgroup storage access OK
  #281/p invalid cgroup storage access 1 OK
  #282/p invalid cgroup storage access 2 OK
  #283/p invalid per-cgroup storage access 3 OK
  #284/p invalid cgroup storage access 4 OK
  #285/p invalid cgroup storage access 5 OK
  ...
  #649/p pass modified ctx pointer to helper, 2 OK
  #650/p pass modified ctx pointer to helper, 3 OK
  Summary: 901 PASSED, 0 SKIPPED, 0 FAILED
Signed-off-by: NRoman Gushchin <guro@fb.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: NMartin KaFai Lau <kafai@fb.com>
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>

Allocate a temporary cgroup storage to use for bpf program test runs.

Because the test program is not actually attached to a cgroup,
the storage is allocated manually just for the execution
of the bpf program.

If the program is executed multiple times, the storage is not zeroed
on each run, emulating multiple runs of the program, attached to
a real cgroup.
Signed-off-by: NRoman Gushchin <guro@fb.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: NMartin KaFai Lau <kafai@fb.com>
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>

Add BPF_MAP_TYPE_CGROUP_STORAGE maps to the list
of maps types which bpftool recognizes.
Signed-off-by: NRoman Gushchin <guro@fb.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: NJakub Kicinski <jakub.kicinski@netronome.com>
Acked-by: NMartin KaFai Lau <kafai@fb.com>
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>

Sync cgroup storage related changes:
1) new BPF_MAP_TYPE_CGROUP_STORAGE map type
2) struct bpf_cgroup_sotrage_key definition
3) get_local_storage() helper
Signed-off-by: NRoman Gushchin <guro@fb.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: NMartin KaFai Lau <kafai@fb.com>
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>

The bpf_get_local_storage() helper function is used
to get a pointer to the bpf local storage from a bpf program.

It takes a pointer to a storage map and flags as arguments.
Right now it accepts only cgroup storage maps, and flags
argument has to be 0. Further it can be extended to support
other types of local storage: e.g. thread local storage etc.
Signed-off-by: NRoman Gushchin <guro@fb.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: NMartin KaFai Lau <kafai@fb.com>
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>

As there is one-to-one relation between a bpf program
and cgroup local storage map, there is no sense in
creating a map of cgroup local storage maps.

Forbid it explicitly to avoid possible side effects.
Signed-off-by: NRoman Gushchin <guro@fb.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: NMartin KaFai Lau <kafai@fb.com>
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>

BPF_MAP_TYPE_CGROUP_STORAGE maps are special in a way
that the access from the bpf program side is lookup-free.
That means the result is guaranteed to be a valid
pointer to the cgroup storage; no NULL-check is required.

This patch introduces BPF_PTR_TO_MAP_VALUE return type,
which is required to cause the verifier accept programs,
which are not checking the map value pointer for being NULL.
Signed-off-by: NRoman Gushchin <guro@fb.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: NMartin KaFai Lau <kafai@fb.com>
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>

This patch converts bpf_prog_array from an array of prog pointers
to the array of struct bpf_prog_array_item elements.

This allows to save a cgroup storage pointer for each bpf program
efficiently attached to a cgroup.
Signed-off-by: NRoman Gushchin <guro@fb.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: NMartin KaFai Lau <kafai@fb.com>
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>

If a bpf program is using cgroup local storage, allocate
a bpf_cgroup_storage structure automatically on attaching the program
to a cgroup and save the pointer into the corresponding bpf_prog_list
entry.
Analogically, release the cgroup local storage on detaching
of the bpf program.
Signed-off-by: NRoman Gushchin <guro@fb.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: NMartin KaFai Lau <kafai@fb.com>
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>

This commit introduces the bpf_cgroup_storage_set() helper,
which will be used to pass a pointer to a cgroup storage
to the bpf helper.
Signed-off-by: NRoman Gushchin <guro@fb.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: NMartin KaFai Lau <kafai@fb.com>
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>

This commit introduces BPF_MAP_TYPE_CGROUP_STORAGE maps:
a special type of maps which are implementing the cgroup storage.

>From the userspace point of view it's almost a generic
hash map with the (cgroup inode id, attachment type) pair
used as a key.

The only difference is that some operations are restricted:
  1) a user can't create new entries,
  2) a user can't remove existing entries.

The lookup from userspace is o(log(n)).
Signed-off-by: NRoman Gushchin <guro@fb.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: NMartin KaFai Lau <kafai@fb.com>
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>

This commits extends existing bpf maps memory charging API
to support dynamic charging/uncharging.

This is required to account memory used by maps,
if all entries are created dynamically after
the map initialization.
Signed-off-by: NRoman Gushchin <guro@fb.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: NMartin KaFai Lau <kafai@fb.com>
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>

When check_alu_op() handles a BPF_MOV64 between two registers,
it calls check_reg_arg(DST_OP) on the dst register, marking it
as unbounded. If the src and dst register are the same, this
marks the src as unbounded, which can lead to unexpected errors
for further checks that rely on bounds info. For example:

	BPF_MOV64_IMM(BPF_REG_2, 0),
	BPF_MOV64_REG(BPF_REG_2, BPF_REG_2),
	BPF_ALU64_REG(BPF_ADD, BPF_REG_1, BPF_REG_2),
	BPF_MOV64_IMM(BPF_REG_0, 0),
	BPF_EXIT_INSN(),

Results in:

	"math between ctx pointer and register with unbounded
	min value is not allowed"

check_alu_op() now uses check_reg_arg(DST_OP_NO_MARK), and MOVs
that need to mark the dst register (MOVIMM, MOV32) do so.

Added a test case for MOV64 dst == src, and dst != src.
Signed-off-by: NArthur Fabre <afabre@cloudflare.com>
Acked-by: NEdward Cree <ecree@solarflare.com>
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>

Add test to use get_socket_cookie() from BPF programs of types
BPF_PROG_TYPE_SOCK_OPS and BPF_PROG_TYPE_CGROUP_SOCK_ADDR.

The test attaches two programs to cgroup, runs TCP server and client in
the cgroup and checks that two operations are done properly on client
socket when user calls connect(2):

1. In BPF_CGROUP_INET6_CONNECT socket cookie is used as the key to write
   new value in a map for client socket.

2. In BPF_CGROUP_SOCK_OPS (BPF_SOCK_OPS_TCP_CONNECT_CB callback) the
   value written in "1." is found by socket cookie, since it's the same
   socket, and updated.

Finally the test verifies the value in the map.
Signed-off-by: NAndrey Ignatov <rdna@fb.com>
Acked-by: NYonghong Song <yhs@fb.com>
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>

Add missing helper to bpf_helpers.h that is used in tests and samples.
Signed-off-by: NAndrey Ignatov <rdna@fb.com>
Acked-by: NYonghong Song <yhs@fb.com>
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>

Sync bpf_get_socket_cookie() related bpf UAPI changes to tools/.
Signed-off-by: NAndrey Ignatov <rdna@fb.com>
Acked-by: NYonghong Song <yhs@fb.com>
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>

bpf_get_socket_cookie() helper can be used to identify skb that
correspond to the same socket.

Though socket cookie can be useful in many other use-cases where socket is
available in program context. Specifically BPF_PROG_TYPE_CGROUP_SOCK_ADDR
and BPF_PROG_TYPE_SOCK_OPS programs can benefit from it so that one of
them can augment a value in a map prepared earlier by other program for
the same socket.

The patch adds support to call bpf_get_socket_cookie() from
BPF_PROG_TYPE_CGROUP_SOCK_ADDR and BPF_PROG_TYPE_SOCK_OPS.

It doesn't introduce new helpers. Instead it reuses same helper name
bpf_get_socket_cookie() but adds support to this helper to accept
`struct bpf_sock_addr` and `struct bpf_sock_ops`.

Documentation in bpf.h is changed in a way that should not break
automatic generation of markdown.
Signed-off-by: NAndrey Ignatov <rdna@fb.com>
Acked-by: NYonghong Song <yhs@fb.com>
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>

'app' is dereferenced before used for the devlink trace point.
In case FW is buggy and sends a control message to a VF queue
we should make sure app is not NULL.
Reported-by: NDan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: NJakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: NDirk van der Merwe <dirk.vandermerwe@netronome.com>
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>

run_lwt_bpf is called by bpf_{input/output/xmit}.
These functions are already protected by rcu_read_lock.
because lwtunnel_{input/output/xmit} holds rcu_read_lock
and then calls bpf_{input/output/xmit}.
So that rcu_read_lock in the run_lwt_bpf is unnecessary.
Signed-off-by: NTaehee Yoo <ap420073@gmail.com>
Acked-by: NYonghong Song <yhs@fb.com>
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>

The seg6local LWT provides the End.DT6 action, which allows to
decapsulate an outer IPv6 header containing a Segment Routing Header
(SRH), full specification is available here:

https://tools.ietf.org/html/draft-filsfils-spring-srv6-network-programming-05

This patch adds this action now to the seg6local BPF
interface. Since it is not mandatory that the inner IPv6 header also
contains a SRH, seg6_bpf_srh_state has been extended with a pointer to
a possible SRH of the outermost IPv6 header. This helps assessing if the
validation must be triggered or not, and avoids some calls to
ipv6_find_hdr.

v3: s/1/true, s/0/false for boolean values
v2: - changed true/false -> 1/0
    - preempt_enable no longer called in first conditional block
Signed-off-by: NMathieu Xhonneux <m.xhonneux@gmail.com>
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>

Commit 531b014e ("tools: bpf: make use of reallocarray") causes
a compiler error when building the perf tool in the linux-next tree.
Compile file tools/lib/bpf/libbpf.c on a FEDORA 28 installation with
gcc compiler version: gcc (GCC) 8.0.1 20180324 (Red Hat 8.0.1-0.20)
shows this error message:

  [root@p23lp27] # make V=1 EXTRA_CFLAGS="-Wp,-D_FORTIFY_SOURCE=2 -O2"
  [...]
  make -f /home6/tmricht/linux-next/tools/build/Makefile.build
  	dir=./util/scripting-engines obj=libperf
  libbpf.c: In function ‘bpf_object__elf_collect’:
  libbpf.c:811:15: error: ignoring return value of ‘strerror_r’,
  		declared with attribute warn_unused_result [-Werror=unused-result]
       strerror_r(-err, errmsg, sizeof(errmsg));
                 ^
  cc1: all warnings being treated as errors
  mv: cannot stat './.libbpf.o.tmp': No such file or directory
  /home6/tmricht/linux-next/tools/build/Makefile.build:96: recipe for target 'libbpf.o' failed

Replace all occurrences of strerror() by calls to strerror_r(). To
keep the compiler quiet also use the return value from strerror_r()
otherwise a 'variable set but not use' warning which is treated as
error terminates the compile.

Fixes: 531b014e ("tools: bpf: make use of reallocarray")
Suggested-by: NJakub Kicinski <jakub.kicinski@netronome.com>
Suggested-by: NDaniel Borkmann <daniel@iogearbox.net>
Signed-off-by: NThomas Richter <tmricht@linux.ibm.com>
Reviewed-by: NHendrik Brueckner <brueckner@linux.ibm.com>
Reviewed-by: NJakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>

Tobin C. Harding says:

====================
Recently BPF docs were converted to RST format. A couple of things were
missed:

 - Use 'index.rst' instead of 'README.rst'.  Although README.rst will
   work just fine it is more typical to keep the subdirectory indices
   in a file called 'index.rst'.

 - Integrate files Documentation/bpf/*.rst into build system using
   toctree in Documentation/bpf/index.rst

 - Include bpf/index in top level toctree so bpf is indexed in the main
   kernel docs.

 - Make anal change to heading format (inline with rest of Documentation/).
====================
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>

The majority of files in the kernel documentation index use
capitalisation for all words, especially the shorter ones.  BPF docs
better fit in with the rest of the documentation if the heading is all
capitalised.

Capitalise document heading.
Signed-off-by: NTobin C. Harding <me@tobin.cc>
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>

Recently bpf docs were converted to RST format.  The new files were not
added to the top level toctree.  This causes build system to emit a
warning of type

	WARNING: document isn't included in any toctree

Add bpf/index.rst to Documentation/index.rst
Signed-off-by: NTobin C. Harding <me@tobin.cc>
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>

Recently bpf/ docs were converted to us RST format.  bp/index.rst was
created out of README but toctree was not added to include files within
Documentation/bpf/

Add toctree to Documentation/bpf/index.rst
Signed-off-by: NTobin C. Harding <me@tobin.cc>
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>

Recently bpf/ docs were converted to use RST format.  'README.rst' was
created but in order to fit in with the Sphinx build system this file
should be named 'index.rst'.  Rename file, fixes to integrate into
Sphinx build system in following patches.

docs: Rename Documentation/bpf/README.rst to Documentation/bpf/index.rst
Signed-off-by: NTobin C. Harding <me@tobin.cc>
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>

Jakub Kicinski says:

====================
This set converts xdpsock_user.c and xdp_fwd_user.c to use libbpf instead
of bpf_load.o.  First two patches are minor improvements to libbpf to make
the conversion (and use of libbpf in general) nicer.
====================
Acked-by: NYonghong Song <yhs@fb.com>
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>

Convert xdpsock_user.c to use libbpf instead of bpf_load.o.
Signed-off-by: NJakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: NQuentin Monnet <quentin.monnet@netronome.com>
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>

Convert xdp_fwd_user.c to use libbpf instead of bpf_load.o.
Signed-off-by: NJakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: NQuentin Monnet <quentin.monnet@netronome.com>
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>

Allow users to find programs by section names.
Signed-off-by: NJakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: NQuentin Monnet <quentin.monnet@netronome.com>
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>

bpf_map__fd() handles NULL map gracefully and returns -EINVAL.
bpf_program__fd() and bpf_program__nth_fd() crash in this case.
Make the behaviour more consistent by validating prog pointer
as well.
Signed-off-by: NJakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: NQuentin Monnet <quentin.monnet@netronome.com>
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>

Jakub Kicinski says:

====================
This set is focused on improving the performance of perf events
reported from BPF offload.  Perf events can now be received on
packet data queues, which significantly improves the performance
(from total of 0.5 Msps to 5Msps per core).  To get to this
performance we need a fast path for control messages which will
operate on raw buffers and recycle them immediately.

Patch 5 replaces the map pointers for perf maps with map IDs.
We look the pointers up in a hashtable, anyway, to validate they
are correct, so there is no performance difference.  Map IDs
have the advantage of being easier to understand for users in
case of errors (we no longer print raw pointers to the logs).

Last patch improves info messages about map offload.
====================
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>

FW can put constraints on map element size to maximize resource
use and efficiency.  When user attempts offload of a map which
does not fit into those constraints an informational message is
printed to kernel logs to inform user about the reason offload
failed.  Map offload does not have access to any advanced error
reporting like verifier log or extack.  There is also currently
no way for us to nicely expose the FW capabilities to user
space.  Given all those constraints we should make sure log
messages are as informative as possible.  Improve them.
Signed-off-by: NJakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: NDirk van der Merwe <dirk.vandermerwe@netronome.com>
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>

Record perf maps by map ID, not raw kernel pointer.  This helps
with debug messages, because printing pointers to logs is frowned
upon, and makes debug easier for the users, as map ID is something
they should be more familiar with.  Note that perf maps are offload
neutral, therefore IDs won't be orphaned.

While at it use a rate limited print helper for the error message.
Reported-by: NKees Cook <keescook@chromium.org>
Signed-off-by: NJakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: NDirk van der Merwe <dirk.vandermerwe@netronome.com>
Reviewed-by: NQuentin Monnet <quentin.monnet@netronome.com>
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>