Commit Graph

25010 Commits

Author SHA1 Message Date
Cong Wang
d6378af615 selftests/bpf: Add a test case for udp sockmap
Add a test case to ensure redirection between two UDP sockets work.

Signed-off-by: Cong Wang <cong.wang@bytedance.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20210331023237.41094-16-xiyou.wangcong@gmail.com
2021-04-01 10:56:14 -07:00
Cong Wang
a7ba4558e6 sock_map: Introduce BPF_SK_SKB_VERDICT
Reusing BPF_SK_SKB_STREAM_VERDICT is possible but its name is
confusing and more importantly we still want to distinguish them
from user-space. So we can just reuse the stream verdict code but
introduce a new type of eBPF program, skb_verdict. Users are not
allowed to attach stream_verdict and skb_verdict programs to the
same map.

Signed-off-by: Cong Wang <cong.wang@bytedance.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/bpf/20210331023237.41094-10-xiyou.wangcong@gmail.com
2021-04-01 10:56:14 -07:00
Stanislav Fomichev
e27bfefb21 tools/resolve_btfids: Fix warnings
* make eprintf static, used only in main.c
* initialize ret in eprintf
* remove unused *tmp

v3:
* remove another err (Song Liu)

v2:
* remove unused 'int err = -1'

Signed-off-by: Stanislav Fomichev <sdf@google.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Song Liu <songliubraving@fb.com>
Link: https://lore.kernel.org/bpf/20210329223143.3659983-1-sdf@google.com
2021-03-31 12:09:12 -07:00
KP Singh
63f8af0fc3 selftests/bpf: Add an option for a debug shell in vmtest.sh
The newly introduced -s command line option starts an interactive shell.
If a command is specified, the shell is started after the command
finishes executing. It's useful to have a shell especially when
debugging failing tests or developing new tests.

Since the user may terminate the VM forcefully, an extra "sync" is added
after the execution of the command to persist any logs from the command
into the log file.

Signed-off-by: KP Singh <kpsingh@kernel.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20210323014752.3198283-1-kpsingh@kernel.org
2021-03-30 22:05:23 -07:00
Björn Töpel
ae6b6a1780 selftests: xsk: Remove unused defines
Remove two unused defines.

Signed-off-by: Björn Töpel <bjorn.topel@intel.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20210329224316.17793-18-maciej.fijalkowski@intel.com
2021-03-30 09:24:40 -07:00
Björn Töpel
96539f1c5e selftests: xsk: Remove mutex and condition variable
The usage of the condition variable is broken, and overkill. Replace it
with a pthread barrier.

Signed-off-by: Björn Töpel <bjorn.topel@intel.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20210329224316.17793-17-maciej.fijalkowski@intel.com
2021-03-30 09:24:40 -07:00
Björn Töpel
7651910257 selftests: xsk: Remove thread attribute
There is really no reason to have a non-default thread stack
size. Remove that.

Signed-off-by: Björn Töpel <bjorn.topel@intel.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20210329224316.17793-16-maciej.fijalkowski@intel.com
2021-03-30 09:24:40 -07:00
Maciej Fijalkowski
27e1ca2525 selftests: xsk: Implement bpf_link test
Introduce a test that is supposed to verify the persistence of BPF
resources based on underlying bpf_link usage.

Test will:
1) create and bind two sockets on queue ids 0 and 1
2) run a traffic on queue ids 0
3) remove xsk sockets from queue 0 on both veth interfaces
4) run a traffic on queues ids 1

Running traffic successfully on qids 1 means that BPF resources were
not removed on step 3).

In order to make it work, change the command that creates veth pair to
have the 4 queue pairs by default.

Introduce the arrays of xsks and umems to ifobject struct but keep a
pointers to single entities, so rest of the logic around Rx/Tx can be
kept as-is.

For umem handling, double the size of mmapped space and split that
between the two sockets.

Rename also bidi_pass to a variable 'second_step' of a boolean type as
it's now used also for the test that is introduced here and it doesn't
have anything in common with bi-directional testing.

Drop opt_queue command line argument as it wasn't working before anyway.

Signed-off-by: Maciej Fijalkowski <maciej.fijalkowski@intel.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20210329224316.17793-15-maciej.fijalkowski@intel.com
2021-03-30 09:24:39 -07:00
Maciej Fijalkowski
0464b1ed07 selftests: xsk: Remove sync_mutex_tx and atomic var
Although thread_common_ops() are called in both Tx and Rx threads,
testapp_validate() will not spawn Tx thread until Rx thread signals that
it has finished its initialization via condition variable.

Therefore, locking in thread_common_ops is not needed and furthermore Tx
thread does not have to spin on atomic variable.

Note that this simplification wouldn't be possible if there would still
be a common worker thread.

Signed-off-by: Maciej Fijalkowski <maciej.fijalkowski@intel.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20210329224316.17793-13-maciej.fijalkowski@intel.com
2021-03-30 09:24:39 -07:00
Maciej Fijalkowski
9445f8c765 selftests: xsk: Refactor teardown/bidi test cases and testapp_validate
Currently, there is a testapp_sockets() that acts like a wrapper around
testapp_validate() and it is called for bidi and teardown test types.
Other test types call testapp_validate() directly.

Split testapp_sockets() onto two separate functions so a bunch of bidi
specific logic can be moved there and out of testapp_validate() itself.

Introduce function pointer to ifobject struct which will be used for
assigning the Rx/Tx function that is assigned to worker thread. Let's
also have a global ifobject Rx/Tx pointers so it's easier to swap the
vectors on a second run of a bi-directional test. Thread creation now is
easey to follow.

switching_notify variable is useless, info about vector switch can be
printed based on bidi_pass state.

Last but not least, init/destroy synchronization variables only once,
not per each test.

Signed-off-by: Maciej Fijalkowski <maciej.fijalkowski@intel.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20210329224316.17793-12-maciej.fijalkowski@intel.com
2021-03-30 09:24:39 -07:00
Maciej Fijalkowski
99f9bcb657 selftests: xsk: Remove Tx synchronization resources
Tx thread needs to be started after the Rx side is fully initialized so
that packets are not xmitted until xsk Rx socket is ready to be used.

It can be observed that atomic variable spinning_tx is not checked from
Rx side in any way, so thread_common_ops can be modified to only address
the spinning_rx. This means that spinning_tx can be removed altogheter.

signal_tx_condition is never utilized, so simply remove it.

Signed-off-by: Maciej Fijalkowski <maciej.fijalkowski@intel.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20210329224316.17793-11-maciej.fijalkowski@intel.com
2021-03-30 09:24:39 -07:00
Maciej Fijalkowski
9866bcd663 selftests: xsk: Split worker thread
Let's a have a separate Tx/Rx worker threads instead of a one common
thread packed with Tx/Rx specific checks.

Move mmap for umem buffer space and a switch_namespace() call to
thread_common_ops.

This also allows for a bunch of simplifactions that are the subject of
the next commits. The final result will be a code base that is much
easier to follow.

Signed-off-by: Maciej Fijalkowski <maciej.fijalkowski@intel.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20210329224316.17793-10-maciej.fijalkowski@intel.com
2021-03-30 09:24:39 -07:00
Maciej Fijalkowski
ef92807897 selftests: xsk: Remove thread for netns switch
Currently, there is a dedicated thread for following remote ns operations:
- grabbing the ifindex of the interface moved to remote netns
- removing xdp prog from that interface

With bpf_link usage in place, this can be simply omitted, so remove
mentioned thread, as BPF resources will be managed by bpf_link itself,
so there's no further need for creating the thread that will switch to
remote netns and do the cleanup.

Keep most of the logic for switching the ns, though, but make
switch_namespace() return the fd so that it will be possible to close it
at the process termination time. Get rid of logic around making sure
that it's possible to switch ns in validate_interfaces().

Signed-off-by: Maciej Fijalkowski <maciej.fijalkowski@intel.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20210329224316.17793-9-maciej.fijalkowski@intel.com
2021-03-30 09:24:39 -07:00
Maciej Fijalkowski
10397994d3 libbpf: xsk: Use bpf_link
Currently, if there are multiple xdpsock instances running on a single
interface and in case one of the instances is terminated, the rest of
them are left in an inoperable state due to the fact of unloaded XDP
prog from interface.

Consider the scenario below:

// load xdp prog and xskmap and add entry to xskmap at idx 10
$ sudo ./xdpsock -i ens801f0 -t -q 10

// add entry to xskmap at idx 11
$ sudo ./xdpsock -i ens801f0 -t -q 11

terminate one of the processes and another one is unable to work due to
the fact that the XDP prog was unloaded from interface.

To address that, step away from setting bpf prog in favour of bpf_link.
This means that refcounting of BPF resources will be done automatically
by bpf_link itself.

Provide backward compatibility by checking if underlying system is
bpf_link capable. Do this by looking up/creating bpf_link on loopback
device. If it failed in any way, stick with netlink-based XDP prog.
therwise, use bpf_link-based logic.

When setting up BPF resources during xsk socket creation, check whether
bpf_link for a given ifindex already exists via set of calls to
bpf_link_get_next_id -> bpf_link_get_fd_by_id -> bpf_obj_get_info_by_fd
and comparing the ifindexes from bpf_link and xsk socket.

For case where resources exist but they are not AF_XDP related, bail out
and ask user to remove existing prog and then retry.

Lastly, do a bit of refactoring within __xsk_setup_xdp_prog and pull out
existing code branches based on prog_id value onto separate functions
that are responsible for resource initialization if prog_id was 0 and
for lookup existing resources for non-zero prog_id as that implies that
XDP program is present on the underlying net device. This in turn makes
it easier to follow, especially the teardown part of both branches.

Signed-off-by: Maciej Fijalkowski <maciej.fijalkowski@intel.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20210329224316.17793-7-maciej.fijalkowski@intel.com
2021-03-30 09:24:38 -07:00
Maciej Fijalkowski
aa2d61c154 selftests: xsk: Simplify frame traversal in dumping thread
Store offsets to each layer in a separate variables rather than compute
them every single time.

Signed-off-by: Björn Töpel <bjorn.topel@intel.com>
Signed-off-by: Maciej Fijalkowski <maciej.fijalkowski@intel.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20210329224316.17793-6-maciej.fijalkowski@intel.com
2021-03-30 09:24:38 -07:00
Maciej Fijalkowski
965d2cb0f6 selftests: xsk: Remove inline keyword from source file
Follow the kernel coding style guidelines and let compiler do the
decision about inlining.

Signed-off-by: Maciej Fijalkowski <maciej.fijalkowski@intel.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20210329224316.17793-5-maciej.fijalkowski@intel.com
2021-03-30 09:24:38 -07:00
Maciej Fijalkowski
7519c387e6 selftests: xsk: Remove unused function
Probably it was ported from xdpsock but is not used anywhere.

Signed-off-by: Maciej Fijalkowski <maciej.fijalkowski@intel.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20210329224316.17793-4-maciej.fijalkowski@intel.com
2021-03-30 09:24:38 -07:00
Maciej Fijalkowski
e623bfdef7 selftests: xsk: Remove struct ifaceconfigobj
ifaceconfigobj is not really useful, it is possible to keep the
functionality and simplify the code.

Signed-off-by: Maciej Fijalkowski <maciej.fijalkowski@intel.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20210329224316.17793-3-maciej.fijalkowski@intel.com
2021-03-30 09:24:38 -07:00
Maciej Fijalkowski
9f33df73a9 selftests: xsk: Don't call worker_pkt_dump() for stats test
For TEST_TYPE_STATS, worker_pkt_validate() that places frames onto
pkt_buf is not called. Therefore, when dump mode is set, don't call
worker_pkt_dump() for mentioned test type, so that it won't crash on
pkt_buf() access.

Signed-off-by: Maciej Fijalkowski <maciej.fijalkowski@intel.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20210329224316.17793-2-maciej.fijalkowski@intel.com
2021-03-30 09:24:38 -07:00
Andrii Nakryiko
05d817031f libbpf: Fix memory leak when emitting final btf_ext
Free temporary allocated memory used to construct finalized .BTF.ext data.
Found by Coverity static analysis on libbpf's Github repo.

Fixes: 8fd27bf69b ("libbpf: Add BPF static linker BTF and BTF.ext support")
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Song Liu <songliubraving@fb.com>
Link: https://lore.kernel.org/bpf/20210327042502.969745-1-andrii@kernel.org
2021-03-30 07:38:36 -07:00
Martin KaFai Lau
2ba4badca9 bpf: selftests: Update clang requirement in README.rst for testing kfunc call
This patch updates the README.rst to specify the clang requirement
to compile the bpf selftests that call kernel function.

Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Song Liu <songliubraving@fb.com>
Link: https://lore.kernel.org/bpf/20210330054156.2933804-1-kafai@fb.com
2021-03-30 07:31:01 -07:00
Martin KaFai Lau
7bd1590d4e bpf: selftests: Add kfunc_call test
This patch adds a few kernel function bpf_kfunc_call_test*() for the
selftest's test_run purpose.  They will be allowed for tc_cls prog.

The selftest calling the kernel function bpf_kfunc_call_test*()
is also added in this patch.

Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20210325015252.1551395-1-kafai@fb.com
2021-03-26 20:41:52 -07:00
Martin KaFai Lau
78e60bbbe8 bpf: selftests: Bpf_cubic and bpf_dctcp calling kernel functions
This patch removes the bpf implementation of tcp_slow_start()
and tcp_cong_avoid_ai().  Instead, it directly uses the kernel
implementation.

It also replaces the bpf_cubic_undo_cwnd implementation by directly
calling tcp_reno_undo_cwnd().  bpf_dctcp also directly calls
tcp_reno_cong_avoid() instead.

Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20210325015246.1551062-1-kafai@fb.com
2021-03-26 20:41:52 -07:00
Martin KaFai Lau
39cd9e0f67 bpf: selftests: Rename bictcp to bpf_cubic
As a similar chanage in the kernel, this patch gives the proper
name to the bpf cubic.

Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20210325015240.1550074-1-kafai@fb.com
2021-03-26 20:41:51 -07:00
Martin KaFai Lau
5bd022ec01 libbpf: Support extern kernel function
This patch is to make libbpf able to handle the following extern
kernel function declaration and do the needed relocations before
loading the bpf program to the kernel.

extern int foo(struct sock *) __attribute__((section(".ksyms")))

In the collect extern phase, needed changes is made to
bpf_object__collect_externs() and find_extern_btf_id() to collect
extern function in ".ksyms" section.  The func in the BTF datasec also
needs to be replaced by an int var.  The idea is similar to the existing
handling in extern var.  In case the BTF may not have a var, a dummy ksym
var is added at the beginning of bpf_object__collect_externs()
if there is func under ksyms datasec.  It will also change the
func linkage from extern to global which the kernel can support.
It also assigns a param name if it does not have one.

In the collect relo phase, it will record the kernel function
call as RELO_EXTERN_FUNC.

bpf_object__resolve_ksym_func_btf_id() is added to find the func
btf_id of the running kernel.

During actual relocation, it will patch the BPF_CALL instruction with
src_reg = BPF_PSEUDO_FUNC_CALL and insn->imm set to the running
kernel func's btf_id.

The required LLVM patch: https://reviews.llvm.org/D93563

Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20210325015234.1548923-1-kafai@fb.com
2021-03-26 20:41:51 -07:00
Martin KaFai Lau
aa0b8d43e9 libbpf: Record extern sym relocation first
This patch records the extern sym relocs first before recording
subprog relocs.  The later patch will have relocs for extern
kernel function call which is also using BPF_JMP | BPF_CALL.
It will be easier to handle the extern symbols first in
the later patch.

is_call_insn() helper is added.  The existing is_ldimm64() helper
is renamed to is_ldimm64_insn() for consistency.

Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20210325015227.1548623-1-kafai@fb.com
2021-03-26 20:41:51 -07:00
Martin KaFai Lau
0c091e5c2d libbpf: Rename RELO_EXTERN to RELO_EXTERN_VAR
This patch renames RELO_EXTERN to RELO_EXTERN_VAR.
It is to avoid the confusion with a later patch adding
RELO_EXTERN_FUNC.

Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20210325015221.1547722-1-kafai@fb.com
2021-03-26 20:41:51 -07:00
Martin KaFai Lau
774e132e83 libbpf: Refactor codes for finding btf id of a kernel symbol
This patch refactors code, that finds kernel btf_id by kind
and symbol name, to a new function find_ksym_btf_id().

It also adds a new helper __btf_kind_str() to return
a string by the numeric kind value.

Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20210325015214.1547069-1-kafai@fb.com
2021-03-26 20:41:51 -07:00
Martin KaFai Lau
933d1aa324 libbpf: Refactor bpf_object__resolve_ksyms_btf_id
This patch refactors most of the logic from
bpf_object__resolve_ksyms_btf_id() into a new function
bpf_object__resolve_ksym_var_btf_id().
It is to get ready for a later patch adding
bpf_object__resolve_ksym_func_btf_id() which resolves
a kernel function to the running kernel btf_id.

Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20210325015207.1546749-1-kafai@fb.com
2021-03-26 20:41:51 -07:00
Martin KaFai Lau
e6ac2450d6 bpf: Support bpf program calling kernel function
This patch adds support to BPF verifier to allow bpf program calling
kernel function directly.

The use case included in this set is to allow bpf-tcp-cc to directly
call some tcp-cc helper functions (e.g. "tcp_cong_avoid_ai()").  Those
functions have already been used by some kernel tcp-cc implementations.

This set will also allow the bpf-tcp-cc program to directly call the
kernel tcp-cc implementation,  For example, a bpf_dctcp may only want to
implement its own dctcp_cwnd_event() and reuse other dctcp_*() directly
from the kernel tcp_dctcp.c instead of reimplementing (or
copy-and-pasting) them.

The tcp-cc kernel functions mentioned above will be white listed
for the struct_ops bpf-tcp-cc programs to use in a later patch.
The white listed functions are not bounded to a fixed ABI contract.
Those functions have already been used by the existing kernel tcp-cc.
If any of them has changed, both in-tree and out-of-tree kernel tcp-cc
implementations have to be changed.  The same goes for the struct_ops
bpf-tcp-cc programs which have to be adjusted accordingly.

This patch is to make the required changes in the bpf verifier.

First change is in btf.c, it adds a case in "btf_check_func_arg_match()".
When the passed in "btf->kernel_btf == true", it means matching the
verifier regs' states with a kernel function.  This will handle the
PTR_TO_BTF_ID reg.  It also maps PTR_TO_SOCK_COMMON, PTR_TO_SOCKET,
and PTR_TO_TCP_SOCK to its kernel's btf_id.

In the later libbpf patch, the insn calling a kernel function will
look like:

insn->code == (BPF_JMP | BPF_CALL)
insn->src_reg == BPF_PSEUDO_KFUNC_CALL /* <- new in this patch */
insn->imm == func_btf_id /* btf_id of the running kernel */

[ For the future calling function-in-kernel-module support, an array
  of module btf_fds can be passed at the load time and insn->off
  can be used to index into this array. ]

At the early stage of verifier, the verifier will collect all kernel
function calls into "struct bpf_kfunc_desc".  Those
descriptors are stored in "prog->aux->kfunc_tab" and will
be available to the JIT.  Since this "add" operation is similar
to the current "add_subprog()" and looking for the same insn->code,
they are done together in the new "add_subprog_and_kfunc()".

In the "do_check()" stage, the new "check_kfunc_call()" is added
to verify the kernel function call instruction:
1. Ensure the kernel function can be used by a particular BPF_PROG_TYPE.
   A new bpf_verifier_ops "check_kfunc_call" is added to do that.
   The bpf-tcp-cc struct_ops program will implement this function in
   a later patch.
2. Call "btf_check_kfunc_args_match()" to ensure the regs can be
   used as the args of a kernel function.
3. Mark the regs' type, subreg_def, and zext_dst.

At the later do_misc_fixups() stage, the new fixup_kfunc_call()
will replace the insn->imm with the function address (relative
to __bpf_call_base).  If needed, the jit can find the btf_func_model
by calling the new bpf_jit_find_kfunc_model(prog, insn).
With the imm set to the function address, "bpftool prog dump xlated"
will be able to display the kernel function calls the same way as
it displays other bpf helper calls.

gpl_compatible program is required to call kernel function.

This feature currently requires JIT.

The verifier selftests are adjusted because of the changes in
the verbose log in add_subprog_and_kfunc().

Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20210325015142.1544736-1-kafai@fb.com
2021-03-26 20:41:51 -07:00
Andrii Nakryiko
36e7985160 libbpf: Preserve empty DATASEC BTFs during static linking
Ensure that BPF static linker preserves all DATASEC BTF types, even if some of
them might not have any variable information at all. This may happen if the
compiler promotes local initialized variable contents into .rodata section and
there are no global or static functions in the program.

For example,

  $ cat t.c
  struct t { char a; char b; char c; };
  void bar(struct t*);
  void find() {
     struct t tmp = {1, 2, 3};
     bar(&tmp);
  }

  $ clang -target bpf -O2 -g -S t.c
         .long   104                             # BTF_KIND_DATASEC(id = 8)
         .long   251658240                       # 0xf000000
         .long   0

         .ascii  ".rodata"                       # string offset=104

  $ clang -target bpf -O2 -g -c t.c
  $ readelf -S t.o | grep data
     [ 4] .rodata           PROGBITS         0000000000000000  00000090

Fixes: 8fd27bf69b ("libbpf: Add BPF static linker BTF and BTF.ext support")
Reported-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20210326043036.3081011-1-andrii@kernel.org
2021-03-26 17:45:17 +01:00
Rafael David Tinoco
155f556d64 libbpf: Add bpf object kern_version attribute setter
Unfortunately some distros don't have their kernel version defined
accurately in <linux/version.h> due to different long term support
reasons.

It is important to have a way to override the bpf kern_version
attribute during runtime: some old kernels might still check for
kern_version attribute during bpf_prog_load().

Signed-off-by: Rafael David Tinoco <rafaeldtinoco@ubuntu.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/bpf/20210323040952.2118241-1-rafaeldtinoco@ubuntu.com
2021-03-25 19:23:27 -07:00
Pedro Tammela
e9bd8cbd97 bpf: selftests: Add tests for batched ops in LPM trie maps
Uses the already existing infrastructure for testing batched ops.
The testing code is essentially the same, with minor tweaks for this use
case.

Suggested-by: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: Pedro Tammela <pctammela@mojatatu.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20210323025058.315763-3-pctammela@gmail.com
2021-03-25 18:51:08 -07:00
KP Singh
cff908463d selftests/bpf: Better error messages for ima_setup.sh failures
The current implementation uses the CHECK_FAIL macro which does not
provide useful error messages when the script fails. Use the CHECK macro
instead and provide more descriptive messages to aid debugging.

Signed-off-by: KP Singh <kpsingh@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20210322170720.2926715-1-kpsingh@kernel.org
2021-03-25 18:39:51 -07:00
Andrii Nakryiko
a46410d5e4 libbpf: Constify few bpf_program getters
bpf_program__get_type() and bpf_program__get_expected_attach_type() shouldn't
modify given bpf_program, so mark input parameter as const struct bpf_program.
This eliminates unnecessary compilation warnings or explicit casts in user
programs.

Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20210324172941.2609884-1-andrii@kernel.org
2021-03-26 01:17:04 +01:00
David S. Miller
241949e488 Merge https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next
Alexei Starovoitov says:

====================
pull-request: bpf-next 2021-03-24

The following pull-request contains BPF updates for your *net-next* tree.

We've added 37 non-merge commits during the last 15 day(s) which contain
a total of 65 files changed, 3200 insertions(+), 738 deletions(-).

The main changes are:

1) Static linking of multiple BPF ELF files, from Andrii.

2) Move drop error path to devmap for XDP_REDIRECT, from Lorenzo.

3) Spelling fixes from various folks.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2021-03-25 16:30:46 -07:00
David S. Miller
efd13b71a3 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-03-25 15:31:22 -07:00
Linus Torvalds
002322402d Merge branch 'akpm' (patches from Andrew)
Merge misc fixes from Andrew Morton:
 "14 patches.

  Subsystems affected by this patch series: mm (hugetlb, kasan, gup,
  selftests, z3fold, kfence, memblock, and highmem), squashfs, ia64,
  gcov, and mailmap"

* emailed patches from Andrew Morton <akpm@linux-foundation.org>:
  mailmap: update Andrey Konovalov's email address
  mm/highmem: fix CONFIG_DEBUG_KMAP_LOCAL_FORCE_MAP
  mm: memblock: fix section mismatch warning again
  kfence: make compatible with kmemleak
  gcov: fix clang-11+ support
  ia64: fix format strings for err_inject
  ia64: mca: allocate early mca with GFP_ATOMIC
  squashfs: fix xattr id and id lookup sanity checks
  squashfs: fix inode lookup sanity checks
  z3fold: prevent reclaim/free race for headless pages
  selftests/vm: fix out-of-tree build
  mm/mmu_notifiers: ensure range_end() is paired with range_start()
  kasan: fix per-page tags for non-page_alloc pages
  hugetlb_cgroup: fix imbalanced css_get and css_put pair for shared mappings
2021-03-25 11:43:43 -07:00
Linus Torvalds
43f0b56259 arm64 fixes for -rc5
- Fix possible memory hotplug failure with KASLR
 
 - Fix FFR value in SVE kselftest
 
 - Fix backtraces reported in /proc/$pid/stack
 
 - Disable broken CnP implementation on NVIDIA Carmel
 
 - Typo fixes and ACPI documentation clarification
 
 - Fix some W=1 warnings
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Merge tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux

Pull arm64 fixes from Will Deacon:
 "Minor fixes all over, ranging from typos to tests to errata
  workarounds:

   - Fix possible memory hotplug failure with KASLR

   - Fix FFR value in SVE kselftest

   - Fix backtraces reported in /proc/$pid/stack

   - Disable broken CnP implementation on NVIDIA Carmel

   - Typo fixes and ACPI documentation clarification

   - Fix some W=1 warnings"

* tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux:
  arm64: kernel: disable CNP on Carmel
  arm64/process.c: fix Wmissing-prototypes build warnings
  kselftest/arm64: sve: Do not use non-canonical FFR register value
  arm64: mm: correct the inside linear map range during hotplug check
  arm64: kdump: update ppos when reading elfcorehdr
  arm64: cpuinfo: Fix a typo
  Documentation: arm64/acpi : clarify arm64 support of IBFT
  arm64: stacktrace: don't trace arch_stack_walk()
  arm64: csum: cast to the proper type
2021-03-25 11:07:40 -07:00
Rong Chen
19ec368cbc selftests/vm: fix out-of-tree build
When building out-of-tree, attempting to make target from $(OUTPUT) directory:

  make[1]: *** No rule to make target '$(OUTPUT)/protection_keys.c', needed by '$(OUTPUT)/protection_keys_32'.

Link: https://lkml.kernel.org/r/20210315094700.522753-1-rong.a.chen@intel.com
Signed-off-by: Rong Chen <rong.a.chen@intel.com>
Reported-by: kernel test robot <lkp@intel.com>
Cc: Shuah Khan <shuah@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-03-25 09:22:55 -07:00
Linus Torvalds
e138138003 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Pull networking fixes from David Miller:
 "Various fixes, all over:

   1) Fix overflow in ptp_qoriq_adjfine(), from Yangbo Lu.

   2) Always store the rx queue mapping in veth, from Maciej
      Fijalkowski.

   3) Don't allow vmlinux btf in map_create, from Alexei Starovoitov.

   4) Fix memory leak in octeontx2-af from Colin Ian King.

   5) Use kvalloc in bpf x86 JIT for storing jit'd addresses, from
      Yonghong Song.

   6) Fix tx ptp stats in mlx5, from Aya Levin.

   7) Check correct ip version in tun decap, fropm Roi Dayan.

   8) Fix rate calculation in mlx5 E-Switch code, from arav Pandit.

   9) Work item memork leak in mlx5, from Shay Drory.

  10) Fix ip6ip6 tunnel crash with bpf, from Daniel Borkmann.

  11) Lack of preemptrion awareness in macvlan, from Eric Dumazet.

  12) Fix data race in pxa168_eth, from Pavel Andrianov.

  13) Range validate stab in red_check_params(), from Eric Dumazet.

  14) Inherit vlan filtering setting properly in b53 driver, from
      Florian Fainelli.

  15) Fix rtnl locking in igc driver, from Sasha Neftin.

  16) Pause handling fixes in igc driver, from Muhammad Husaini
      Zulkifli.

  17) Missing rtnl locking in e1000_reset_task, from Vitaly Lifshits.

  18) Use after free in qlcnic, from Lv Yunlong.

  19) fix crash in fritzpci mISDN, from Tong Zhang.

  20) Premature rx buffer reuse in igb, from Li RongQing.

  21) Missing termination of ip[a driver message handler arrays, from
      Alex Elder.

  22) Fix race between "x25_close" and "x25_xmit"/"x25_rx" in hdlc_x25
      driver, from Xie He.

  23) Use after free in c_can_pci_remove(), from Tong Zhang.

  24) Uninitialized variable use in nl80211, from Jarod Wilson.

  25) Off by one size calc in bpf verifier, from Piotr Krysiuk.

  26) Use delayed work instead of deferrable for flowtable GC, from
      Yinjun Zhang.

  27) Fix infinite loop in NPC unmap of octeontx2 driver, from
      Hariprasad Kelam.

  28) Fix being unable to change MTU of dwmac-sun8i devices due to lack
      of fifo sizes, from Corentin Labbe.

  29) DMA use after free in r8169 with WoL, fom Heiner Kallweit.

  30) Mismatched prototypes in isdn-capi, from Arnd Bergmann.

  31) Fix psample UAPI breakage, from Ido Schimmel"

* git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (171 commits)
  psample: Fix user API breakage
  math: Export mul_u64_u64_div_u64
  ch_ktls: fix enum-conversion warning
  octeontx2-af: Fix memory leak of object buf
  ptp_qoriq: fix overflow in ptp_qoriq_adjfine() u64 calcalation
  net: bridge: don't notify switchdev for local FDB addresses
  net/sched: act_ct: clear post_ct if doing ct_clear
  net: dsa: don't assign an error value to tag_ops
  isdn: capi: fix mismatched prototypes
  net/mlx5: SF, do not use ecpu bit for vhca state processing
  net/mlx5e: Fix division by 0 in mlx5e_select_queue
  net/mlx5e: Fix error path for ethtool set-priv-flag
  net/mlx5e: Offload tuple rewrite for non-CT flows
  net/mlx5e: Allow to match on MPLS parameters only for MPLS over UDP
  net/mlx5: Add back multicast stats for uplink representor
  net: ipconfig: ic_dev can be NULL in ic_close_devs
  MAINTAINERS: Combine "QLOGIC QLGE 10Gb ETHERNET DRIVER" sections into one
  docs: networking: Fix a typo
  r8169: fix DMA being used after buffer free if WoL is enabled
  net: ipa: fix init header command validation
  ...
2021-03-24 18:16:04 -07:00
Ido Schimmel
ffd3e9b07b selftests: mlxsw: Add resilient nexthop groups configuration tests
Test that unsupported resilient nexthop group configurations are
rejected and that offload / trap indication is correctly set on nexthop
buckets in a resilient group.

Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Reviewed-by: Petr Machata <petrm@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-03-24 16:34:58 -07:00
Ido Schimmel
861584724c selftests: mlxsw: Test unresolved neigh trap with resilient nexthop groups
The number of nexthop buckets in a resilient nexthop group never
changes, so when the gateway address of a nexthop cannot be resolved,
the nexthop buckets are programmed to trap packets to the CPU in order
to trigger resolution. For example:

 # ip nexthop add id 1 via 198.51.100.1 dev swp3
 # ip nexthop add id 10 group 1 type resilient buckets 32
 # ip nexthop bucket get id 10 index 0
 id 10 index 0 idle_time 1.44 nhid 1 trap

Where 198.51.100.1 is a made-up IP.

Test that in this case packets are indeed trapped to the CPU via the
unresolved neigh trap.

Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Reviewed-by: Petr Machata <petrm@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-03-24 16:34:58 -07:00
Pablo Neira Ayuso
79d4071ea4 selftests: netfilter: flowtable bridge and vlan support
This patch adds two new tests to cover bridge and vlan support:

- Add a bridge device to the Router1 (nsr1) container and attach the
  veth0 device to the bridge. Set the IP address to the bridge device
  to exercise the bridge forwarding path.

- Add vlan encapsulation between to the bridge device in the Router1 and
  one of the sender containers (ns1).

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-03-24 12:48:39 -07:00
Linus Torvalds
7acac4b319 linux-kselftest-kunit-fixes-5.12-rc5.1
This KUnit update for Linux 5.12-rc5 consists of two fixes to kunit
 tool from David Gow.
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Merge tag 'linux-kselftest-kunit-fixes-5.12-rc5.1' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest

Pull KUnit fixes from Shuah Khan:
 "Two fixes to the kunit tool from David Gow"

* tag 'linux-kselftest-kunit-fixes-5.12-rc5.1' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest:
  kunit: tool: Disable PAGE_POISONING under --alltests
  kunit: tool: Fix a python tuple typing error
2021-03-23 10:18:08 -07:00
Andrii Nakryiko
78b226d481 libbpf: Skip BTF fixup if object file has no BTF
Skip BTF fixup step when input object file is missing BTF altogether.

Fixes: 8fd27bf69b ("libbpf: Add BPF static linker BTF and BTF.ext support")
Reported-by: Jiri Olsa <jolsa@redhat.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Tested-by: Jiri Olsa <jolsa@redhat.com>
Link: https://lore.kernel.org/bpf/20210319205909.1748642-3-andrii@kernel.org
2021-03-22 18:58:25 -07:00
Andre Przywara
7011d72588 kselftest/arm64: sve: Do not use non-canonical FFR register value
The "First Fault Register" (FFR) is an SVE register that mimics a
predicate register, but clears bits when a load or store fails to handle
an element of a vector. The supposed usage scenario is to initialise
this register (using SETFFR), then *read* it later on to learn about
elements that failed to load or store. Explicit writes to this register
using the WRFFR instruction are only supposed to *restore* values
previously read from the register (for context-switching only).
As the manual describes, this register holds only certain values, it:
"... contains a monotonic predicate value, in which starting from bit 0
there are zero or more 1 bits, followed only by 0 bits in any remaining
bit positions."
Any other value is UNPREDICTABLE and is not supposed to be "restored"
into the register.

The SVE test currently tries to write a signature pattern into the
register, which is *not* a canonical FFR value. Apparently the existing
setups treat UNPREDICTABLE as "read-as-written", but a new
implementation actually only stores canonical values. As a consequence,
the sve-test fails immediately when comparing the FFR value:
-----------
 # ./sve-test
Vector length:  128 bits
PID:    207
Mismatch: PID=207, iteration=0, reg=48
        Expected [cf00]
        Got      [0f00]
Aborted
-----------

Fix this by only populating the FFR with proper canonical values.
Effectively the requirement described above limits us to 17 unique
values over 16 bits worth of FFR, so we condense our signature down to 4
bits (2 bits from the PID, 2 bits from the generation) and generate the
canonical pattern from it. Any bits describing elements above the
minimum 128 bit are set to 0.

This aligns the FFR usage to the architecture and fixes the test on
microarchitectures implementing FFR in a more restricted way.

Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Reviwed-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20210319120128.29452-1-andre.przywara@arm.com
Signed-off-by: Will Deacon <will@kernel.org>
2021-03-22 12:49:57 +00:00
David S. Miller
e56c53d194 Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf
Alexei Starovoitov says:

====================
pull-request: bpf 2021-03-20

The following pull-request contains BPF updates for your *net* tree.

We've added 5 non-merge commits during the last 3 day(s) which contain
a total of 8 files changed, 155 insertions(+), 12 deletions(-).

The main changes are:

1) Use correct nops in fexit trampoline, from Stanislav.

2) Fix BTF dump, from Jean-Philippe.

3) Fix umd memory leak, from Zqiang.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2021-03-20 15:18:06 -07:00
Jean-Philippe Brucker
f118aac651 selftests/bpf: Add selftest for pointer-to-array-of-struct BTF dump
Bpftool used to issue forward declarations for a struct used as part of
a pointer to array, which is invalid. Add a test to check that the
struct is fully defined in this case:

	@@ -134,9 +134,9 @@
	 	};
	 };

	-struct struct_in_array {};
	+struct struct_in_array;

	-struct struct_in_array_typed {};
	+struct struct_in_array_typed;

	 typedef struct struct_in_array_typed struct_in_array_t[2];

	@@ -189,3 +189,7 @@
	 	struct struct_with_embedded_stuff _14;
	 };

	+struct struct_in_array {};
	+
	+struct struct_in_array_typed {};
	+
	...
	#13/1 btf_dump: syntax:FAIL

Suggested-by: Andrii Nakryiko <andrii.nakryiko@gmail.com>
Signed-off-by: Jean-Philippe Brucker <jean-philippe@linaro.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20210319112554.794552-3-jean-philippe@linaro.org
2021-03-19 14:14:44 -07:00
Jean-Philippe Brucker
901ee1d750 libbpf: Fix BTF dump of pointer-to-array-of-struct
The vmlinux.h generated from BTF is invalid when building
drivers/phy/ti/phy-gmii-sel.c with clang:

vmlinux.h:61702:27: error: array type has incomplete element type ‘struct reg_field’
61702 |  const struct reg_field (*regfields)[3];
      |                           ^~~~~~~~~

bpftool generates a forward declaration for this struct regfield, which
compilers aren't happy about. Here's a simplified reproducer:

	struct inner {
		int val;
	};
	struct outer {
		struct inner (*ptr_to_array)[2];
	} A;

After build with clang -> bpftool btf dump c -> clang/gcc:
./def-clang.h:11:23: error: array has incomplete element type 'struct inner'
        struct inner (*ptr_to_array)[2];

Member ptr_to_array of struct outer is a pointer to an array of struct
inner. In the DWARF generated by clang, struct outer appears before
struct inner, so when converting BTF of struct outer into C, bpftool
issues a forward declaration to struct inner. With GCC the DWARF info is
reversed so struct inner gets fully defined.

That forward declaration is not sufficient when compilers handle an
array of the struct, even when it's only used through a pointer. Note
that we can trigger the same issue with an intermediate typedef:

	struct inner {
	        int val;
	};
	typedef struct inner inner2_t[2];
	struct outer {
	        inner2_t *ptr_to_array;
	} A;

Becomes:

	struct inner;
	typedef struct inner inner2_t[2];

And causes:

./def-clang.h:10:30: error: array has incomplete element type 'struct inner'
	typedef struct inner inner2_t[2];

To fix this, clear through_ptr whenever we encounter an intermediate
array, to make the inner struct part of a strong link and force full
declaration.

Fixes: 351131b51c ("libbpf: add btf_dump API for BTF-to-C conversion")
Signed-off-by: Jean-Philippe Brucker <jean-philippe@linaro.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20210319112554.794552-2-jean-philippe@linaro.org
2021-03-19 14:14:44 -07:00