Commit Graph

722507 Commits

Author SHA1 Message Date
Alexei Starovoitov
a7ff3eca95 selftests/bpf: add verifier tests for bpf_call
Add extensive set of tests for bpf_call verification logic:

calls: basic sanity
calls: using r0 returned by callee
calls: callee is using r1
calls: callee using args1
calls: callee using wrong args2
calls: callee using two args
calls: callee changing pkt pointers
calls: two calls with args
calls: two calls with bad jump
calls: recursive call. test1
calls: recursive call. test2
calls: unreachable code
calls: invalid call
calls: jumping across function bodies. test1
calls: jumping across function bodies. test2
calls: call without exit
calls: call into middle of ld_imm64
calls: call into middle of other call
calls: two calls with bad fallthrough
calls: two calls with stack read
calls: two calls with stack write
calls: spill into caller stack frame
calls: two calls with stack write and void return
calls: ambiguous return value
calls: two calls that return map_value
calls: two calls that return map_value with bool condition
calls: two calls that return map_value with incorrect bool check
calls: two calls that receive map_value via arg=ptr_stack_of_caller. test1
calls: two calls that receive map_value via arg=ptr_stack_of_caller. test2
calls: two jumps that receive map_value via arg=ptr_stack_of_jumper. test3
calls: two calls that receive map_value_ptr_or_null via arg. test1
calls: two calls that receive map_value_ptr_or_null via arg. test2
calls: pkt_ptr spill into caller stack

Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2017-12-17 20:34:35 +01:00
Alexei Starovoitov
f4d7e40a5b bpf: introduce function calls (verification)
Allow arbitrary function calls from bpf function to another bpf function.

To recognize such set of bpf functions the verifier does:
1. runs control flow analysis to detect function boundaries
2. proceeds with verification of all functions starting from main(root) function
It recognizes that the stack of the caller can be accessed by the callee
(if the caller passed a pointer to its stack to the callee) and the callee
can store map_value and other pointers into the stack of the caller.
3. keeps track of the stack_depth of each function to make sure that total
stack depth is still less than 512 bytes
4. disallows pointers to the callee stack to be stored into the caller stack,
since they will be invalid as soon as the callee returns
5. to reuse all of the existing state_pruning logic each function call
is considered to be independent call from the verifier point of view.
The verifier pretends to inline all function calls it sees are being called.
It stores the callsite instruction index as part of the state to make sure
that two calls to the same callee from two different places in the caller
will be different from state pruning point of view
6. more safety checks are added to liveness analysis

Implementation details:
. struct bpf_verifier_state is now consists of all stack frames that
  led to this function
. struct bpf_func_state represent one stack frame. It consists of
  registers in the given frame and its stack
. propagate_liveness() logic had a premature optimization where
  mark_reg_read() and mark_stack_slot_read() were manually inlined
  with loop iterating over parents for each register or stack slot.
  Undo this optimization to reuse more complex mark_*_read() logic
. skip_callee() logic is not necessary from safety point of view,
  but without it mark_*_read() markings become too conservative,
  since after returning from the funciton call a read of r6-r9
  will incorrectly propagate the read marks into callee causing
  inefficient pruning later
. mark_*_read() logic is now aware of control flow which makes it
  more complex. In the future the plan is to rewrite liveness
  to be hierarchical. So that liveness can be done within
  basic block only and control flow will be responsible for
  propagation of liveness information along cfg and between calls.
. tail_calls and ld_abs insns are not allowed in the programs with
  bpf-to-bpf calls
. returning stack pointers to the caller or storing them into stack
  frame of the caller is not allowed

Testing:
. no difference in cilium processed_insn numbers
. large number of tests follows in next patches

Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2017-12-17 20:34:35 +01:00
Alexei Starovoitov
cc8b0b92a1 bpf: introduce function calls (function boundaries)
Allow arbitrary function calls from bpf function to another bpf function.

Since the beginning of bpf all bpf programs were represented as a single function
and program authors were forced to use always_inline for all functions
in their C code. That was causing llvm to unnecessary inflate the code size
and forcing developers to move code to header files with little code reuse.

With a bit of additional complexity teach verifier to recognize
arbitrary function calls from one bpf function to another as long as
all of functions are presented to the verifier as a single bpf program.
New program layout:
r6 = r1    // some code
..
r1 = ..    // arg1
r2 = ..    // arg2
call pc+1  // function call pc-relative
exit
.. = r1    // access arg1
.. = r2    // access arg2
..
call pc+20 // second level of function call
...

It allows for better optimized code and finally allows to introduce
the core bpf libraries that can be reused in different projects,
since programs are no longer limited by single elf file.
With function calls bpf can be compiled into multiple .o files.

This patch is the first step. It detects programs that contain
multiple functions and checks that calls between them are valid.
It splits the sequence of bpf instructions (one program) into a set
of bpf functions that call each other. Calls to only known
functions are allowed. In the future the verifier may allow
calls to unresolved functions and will do dynamic linking.
This logic supports statically linked bpf functions only.

Such function boundary detection could have been done as part of
control flow graph building in check_cfg(), but it's cleaner to
separate function boundary detection vs control flow checks within
a subprogram (function) into logically indepedent steps.
Follow up patches may split check_cfg() further, but not check_subprogs().

Only allow bpf-to-bpf calls for root only and for non-hw-offloaded programs.
These restrictions can be relaxed in the future.

Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2017-12-17 20:34:35 +01:00
Jakub Kicinski
0bce7c9a60 nfp: bpf: correct printk formats for size_t
Build bot reported warning about invalid printk formats on 32bit
architectures.  Use %zu for size_t and %zd ptr diff.

Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2017-12-15 22:01:05 +01:00
Daniel Borkmann
1c45597ec5 Merge branch 'bpf-nfp-jit-adjust-head-support'
Jakub Kicinski says:

====================
This small set adds support for bpf_xdp_adjust_head() to the offload.
Since we have access to unmodified BPF bytecode translating calls is
pretty trivial.  First part of the series adds handling of BPF
capabilities included in the FW in TLV format.  The last two patches
add adjust head support in the nfp verifier and jit, and a small
optimization in case we can guarantee the constant adjustment
will always meet adjustment constaints.
====================

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2017-12-15 14:18:19 +01:00
Jakub Kicinski
8231f84441 nfp: bpf: optimize the adjust_head calls in trivial cases
If the program is simple and has only one adjust head call
with constant parameters, we can check that the call will
always succeed at translation time.  We need to track the
location of the call and make sure parameters are always
the same.  We also have to check the parameters against
datapath constraints and ETH_HLEN.

Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2017-12-15 14:18:18 +01:00
Jakub Kicinski
0d49eaf4db nfp: bpf: add basic support for adjust head call
Support bpf_xdp_adjust_head().  We need to check whether the
packet offset after adjustment is within datapath's limits.
We also check if the frame is at least ETH_HLEN long (similar
to the kernel implementation).

Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2017-12-15 14:18:18 +01:00
Jakub Kicinski
2cb230bded nfp: bpf: prepare for call support
Add skeleton of verifier checks and translation handler
for call instructions.  Make sure jump target resolution
will not treat them as jumps.

Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2017-12-15 14:18:18 +01:00
Jakub Kicinski
77a844ee65 nfp: bpf: prepare for parsing BPF FW capabilities
BPF FW creates a run time symbol called bpf_capabilities which
contains TLV-formatted capability information.  Allocate app
private structure to store parsed capabilities and add a skeleton
of parsing logic.

Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2017-12-15 14:18:18 +01:00
Jakub Kicinski
a351ab565c nfp: add nfp_cpp_area_size() accessor
Allow users outside of core reading area sizes.  This was not needed
previously because whatever entity created the area would usually know
what size it asked for.  The nfp_rtsym_map() helper, however, will
allocate the area based on the size of an RT-symbol with given name.

Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2017-12-15 14:18:18 +01:00
Daniel Borkmann
7310c23328 Merge branch 'bpf-bpftool-cgroup-ops'
Roman Gushchin says:

====================
This patchset adds basic cgroup bpf operations to bpftool.

Right now there is no convenient way to perform these operations.
The /samples/bpf/load_sock_ops.c implements attach/detacg operations,
but only for BPF_CGROUP_SOCK_OPS programs. Bps (part of bcc) implements
bpf introspection, but lacks any cgroup-related specific.

I find having a tool to perform these basic operations in the kernel tree
very useful, as it can be used in the corresponding bpf documentation
without creating additional dependencies. And bpftool seems to be
a right tool to extend with such functionality.

v4:
  - ATTACH_FLAGS and ATTACH_TYPE are listed and described in docs and usage
  - ATTACH_FLAG names converted to "multi" and "override"
  - do_attach() recognizes ATTACH_FLAG abbreviations, e.g "mul"
  - Local variables sorted ("reverse Christmas tree")
  - unknown attach flags value will be never truncated

v3:
  - SRC replaced with OBJ in prog load docs
  - Output unknown attach type in hex
  - License header in SPDX format
  - Minor style fixes (e.g. variable reordering)

v2:
  - Added prog load operations
  - All cgroup operations are looking like bpftool cgroup <command>
  - All cgroup-related stuff is moved to a separate file
  - Added support for attach flags
  - Added support for attaching/detaching programs by id, pinned name, etc
  - Changed cgroup detach arguments order
  - Added empty json output for succesful programs
  - Style fixed: includes order, strncmp and macroses, error handling
  - Added man pages

v1:
  https://lwn.net/Articles/740366/
====================

Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2017-12-14 13:37:14 +01:00
Roman Gushchin
5ccda64d38 bpftool: implement cgroup bpf operations
This patch adds basic cgroup bpf operations to bpftool:
cgroup list, attach and detach commands.

Usage is described in the corresponding man pages,
and examples are provided.

Syntax:
$ bpftool cgroup list CGROUP
$ bpftool cgroup attach CGROUP ATTACH_TYPE PROG [ATTACH_FLAGS]
$ bpftool cgroup detach CGROUP ATTACH_TYPE PROG

Signed-off-by: Roman Gushchin <guro@fb.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Jakub Kicinski <jakub.kicinski@netronome.com>
Cc: Martin KaFai Lau <kafai@fb.com>
Cc: Quentin Monnet <quentin.monnet@netronome.com>
Reviewed-by: David Ahern <dsahern@gmail.com>
Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2017-12-14 13:37:13 +01:00
Roman Gushchin
49a086c201 bpftool: implement prog load command
Add the prog load command to load a bpf program from a specified
binary file and pin it to bpffs.

Usage description and examples are given in the corresponding man
page.

Syntax:
$ bpftool prog load OBJ FILE

FILE is a non-existing file on bpffs.

Signed-off-by: Roman Gushchin <guro@fb.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Cc: Martin KaFai Lau <kafai@fb.com>
Cc: Quentin Monnet <quentin.monnet@netronome.com>
Cc: David Ahern <dsahern@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2017-12-14 13:37:13 +01:00
Roman Gushchin
fe4d44b23f libbpf: prefer global symbols as bpf program name source
Libbpf picks the name of the first symbol in the corresponding
elf section to use as a program name. But without taking symbol's
scope into account it may end's up with some local label
as a program name. E.g.:

$ bpftool prog
1: type 15  name LBB0_10    tag 0390a5136ba23f5c
	loaded_at Dec 07/17:22  uid 0
	xlated 456B  not jited  memlock 4096B

Fix this by preferring global symbols as program name.

For instance:
$ bpftool prog
1: type 15  name bpf_prog1  tag 0390a5136ba23f5c
	loaded_at Dec 07/17:26  uid 0
	xlated 456B  not jited  memlock 4096B

Signed-off-by: Roman Gushchin <guro@fb.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Jakub Kicinski <jakub.kicinski@netronome.com>
Cc: Martin KaFai Lau <kafai@fb.com>
Cc: Quentin Monnet <quentin.monnet@netronome.com>
Cc: David Ahern <dsahern@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2017-12-14 13:37:13 +01:00
Roman Gushchin
583c90097f libbpf: add ability to guess program type based on section name
The bpf_prog_load() function will guess program type if it's not
specified explicitly. This functionality will be used to implement
loading of different programs without asking a user to specify
the program type. In first order it will be used by bpftool.

Signed-off-by: Roman Gushchin <guro@fb.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Jakub Kicinski <jakub.kicinski@netronome.com>
Cc: Martin KaFai Lau <kafai@fb.com>
Cc: Quentin Monnet <quentin.monnet@netronome.com>
Cc: David Ahern <dsahern@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2017-12-14 13:37:13 +01:00
Yonghong Song
f4e2298e63 bpf/tracing: fix kernel/events/core.c compilation error
Commit f371b304f1 ("bpf/tracing: allow user space to
query prog array on the same tp") introduced a perf
ioctl command to query prog array attached to the
same perf tracepoint. The commit introduced a
compilation error under certain config conditions, e.g.,
  (1). CONFIG_BPF_SYSCALL is not defined, or
  (2). CONFIG_TRACING is defined but neither CONFIG_UPROBE_EVENTS
       nor CONFIG_KPROBE_EVENTS is defined.

Error message:
  kernel/events/core.o: In function `perf_ioctl':
  core.c:(.text+0x98c4): undefined reference to `bpf_event_query_prog_array'

This patch fixed this error by guarding the real definition under
CONFIG_BPF_EVENTS and provided static inline dummy function
if CONFIG_BPF_EVENTS was not defined.
It renamed the function from bpf_event_query_prog_array to
perf_event_query_prog_array and moved the definition from linux/bpf.h
to linux/trace_events.h so the definition is in proximity to
other prog_array related functions.

Fixes: f371b304f1 ("bpf/tracing: allow user space to query prog array on the same tp")
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2017-12-13 22:44:10 +01:00
Alexei Starovoitov
553a8f2f42 Merge branch 'bpf-override-return'
Josef Bacik says:

====================
This is the same as v8, just rebased onto the bpf tree.

v8->v9:
- rebased onto the bpf tree.

v7->v8:
- removed the _ASM_KPROBE_ERROR_INJECT since it was not needed.

v6->v7:
- moved the opt-in macro to bpf.h out of kprobes.h.

v5->v6:
- add BPF_ALLOW_ERROR_INJECTION() tagging for functions that will support this
  feature.  This way only functions that opt-in will be allowed to be
  overridden.
- added a btrfs patch to allow error injection for open_ctree() so that the bpf
  sample actually works.

v4->v5:
- disallow kprobe_override programs from being put in the prog map array so we
  don't tail call into something we didn't check.  This allows us to make the
  normal path still fast without a bunch of percpu operations.

v3->v4:
- fix a build error found by kbuild test bot (I didn't wait long enough
  apparently.)
- Added a warning message as per Daniels suggestion.

v2->v3:
- added a ->kprobe_override flag to bpf_prog.
- added some sanity checks to disallow attaching bpf progs that have
  ->kprobe_override set that aren't for ftrace kprobes.
- added the trace_kprobe_ftrace helper to check if the trace_event_call is a
  ftrace kprobe.
- renamed bpf_kprobe_state to bpf_kprobe_override, fixed it so we only read this
  value in the kprobe path, and thus only write to it if we're overriding or
  clearing the override.

v1->v2:
- moved things around to make sure that bpf_override_return could really only be
  used for an ftrace kprobe.
- killed the special return values from trace_call_bpf.
- renamed pc_modified to bpf_kprobe_state so bpf_override_return could tell if
  it was being called from an ftrace kprobe context.
- reworked the logic in kprobe_perf_func to take advantage of bpf_kprobe_state.
- updated the test as per Alexei's review.

- Original message -

A lot of our error paths are not well tested because we have no good way of
injecting errors generically.  Some subystems (block, memory) have ways to
inject errors, but they are random so it's hard to get reproduceable results.

With BPF we can add determinism to our error injection.  We can use kprobes and
other things to verify we are injecting errors at the exact case we are trying
to test.  This patch gives us the tool to actual do the error injection part.
It is very simple, we just set the return value of the pt_regs we're given to
whatever we provide, and then override the PC with a dummy function that simply
returns.

Right now this only works on x86, but it would be simple enough to expand to
other architectures.  Thanks,

Josef
====================

In patch "bpf: add a bpf_override_function helper" Alexei moved
"ifdef CONFIG_BPF_KPROBE_OVERRIDE" few lines to fail program loading
when kprobe_override is not available instead of failing at run-time.

Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2017-12-12 09:16:56 -08:00
Josef Bacik
023f46c5b8 btrfs: allow us to inject errors at io_ctl_init
This was instrumental in reproducing a space cache bug.

Signed-off-by: Josef Bacik <jbacik@fb.com>
Acked-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2017-12-12 09:02:40 -08:00
Josef Bacik
965de87e54 samples/bpf: add a test for bpf_override_return
This adds a basic test for bpf_override_return to verify it works.  We
override the main function for mounting a btrfs fs so it'll return
-ENOMEM and then make sure that trying to mount a btrfs fs will fail.

Acked-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2017-12-12 09:02:40 -08:00
Josef Bacik
9802d86585 bpf: add a bpf_override_function helper
Error injection is sloppy and very ad-hoc.  BPF could fill this niche
perfectly with it's kprobe functionality.  We could make sure errors are
only triggered in specific call chains that we care about with very
specific situations.  Accomplish this with the bpf_override_funciton
helper.  This will modify the probe'd callers return value to the
specified value and set the PC to an override function that simply
returns, bypassing the originally probed function.  This gives us a nice
clean way to implement systematic error injection for all of our code
paths.

Acked-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2017-12-12 09:02:34 -08:00
Josef Bacik
8556e50994 btrfs: make open_ctree error injectable
This allows us to do error injection with BPF for open_ctree.

Signed-off-by: Josef Bacik <jbacik@fb.com>
Acked-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2017-12-12 08:56:26 -08:00
Josef Bacik
92ace9991d add infrastructure for tagging functions as error injectable
Using BPF we can override kprob'ed functions and return arbitrary
values.  Obviously this can be a bit unsafe, so make this feature opt-in
for functions.  Simply tag a function with KPROBE_ERROR_INJECT_SYMBOL in
order to give BPF access to that function for error injection purposes.

Signed-off-by: Josef Bacik <jbacik@fb.com>
Acked-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2017-12-12 08:56:26 -08:00
Alexei Starovoitov
a23967c181 Merge branch 'bpf-tracing-multiprog-tp-query'
Yonghong Song says:

====================
Commit e87c6bc385 ("bpf: permit multiple bpf attachments
for a single perf event") added support to attach multiple
bpf programs to a single perf event. Given a perf event
(kprobe, uprobe, or kernel tracepoint), the perf ioctl interface
is used to query bpf programs attached to the same trace event.

There already exists a BPF_PROG_QUERY command for introspection
currently used by cgroup+bpf. We did have an implementation for
querying tracepoint+bpf through the same interface. However, it
looks cleaner to use ioctl() style of api here, since attaching
bpf prog to tracepoint/kuprobe is also done via ioctl.

Patch #1 had the core implementation and patch #2 added
a test case in tools bpf selftests suite.

Changelogs:
v3 -> v4:
  - Fix a compilation error with newer gcc like 6.3.1 while
    old gcc 4.8.5 is okay. I was using &uquery->ids to represent
    the address to the ids array to make it explicit that the
    address is passed, and this syntax is rightly rejected
    by gcc 6.3.1.
v2 -> v3:
  - Change uapi structure perf_event_query_bpf to be more
    clearer based on Peter's suggestion, and adjust
    other codes accordingly.
v1 -> v2:
  - Rebase on top of net-next.
  - Use existing bpf_prog_array_length function instead of
    implementing the same functionality in function
    bpf_prog_array_copy_info.
====================

Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2017-12-12 08:49:14 -08:00
Yonghong Song
d279f1f8c6 bpf/tracing: add a bpf test for new ioctl query interface
Added a subtest in test_progs. The tracepoint is
sched/sched_switch. Multiple bpf programs are attached to
this tracepoint and the query interface is exercised.

Signed-off-by: Yonghong Song <yhs@fb.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2017-12-12 08:46:40 -08:00
Yonghong Song
f371b304f1 bpf/tracing: allow user space to query prog array on the same tp
Commit e87c6bc385 ("bpf: permit multiple bpf attachments
for a single perf event") added support to attach multiple
bpf programs to a single perf event.
Although this provides flexibility, users may want to know
what other bpf programs attached to the same tp interface.
Besides getting visibility for the underlying bpf system,
such information may also help consolidate multiple bpf programs,
understand potential performance issues due to a large array,
and debug (e.g., one bpf program which overwrites return code
may impact subsequent program results).

Commit 2541517c32 ("tracing, perf: Implement BPF programs
attached to kprobes") utilized the existing perf ioctl
interface and added the command PERF_EVENT_IOC_SET_BPF
to attach a bpf program to a tracepoint. This patch adds a new
ioctl command, given a perf event fd, to query the bpf program
array attached to the same perf tracepoint event.

The new uapi ioctl command:
  PERF_EVENT_IOC_QUERY_BPF

The new uapi/linux/perf_event.h structure:
  struct perf_event_query_bpf {
       __u32	ids_len;
       __u32	prog_cnt;
       __u32	ids[0];
  };

User space provides buffer "ids" for kernel to copy to.
When returning from the kernel, the number of available
programs in the array is set in "prog_cnt".

The usage:
  struct perf_event_query_bpf *query =
    malloc(sizeof(*query) + sizeof(u32) * ids_len);
  query.ids_len = ids_len;
  err = ioctl(pmu_efd, PERF_EVENT_IOC_QUERY_BPF, query);
  if (err == 0) {
    /* query.prog_cnt is the number of available progs,
     * number of progs in ids: (ids_len == 0) ? 0 : query.prog_cnt
     */
  } else if (errno == ENOSPC) {
    /* query.ids_len number of progs copied,
     * query.prog_cnt is the number of available progs
     */
  } else {
      /* other errors */
  }

Signed-off-by: Yonghong Song <yhs@fb.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2017-12-12 08:46:40 -08:00
Naresh Kamboju
63060c3916 selftests: bpf: Adding config fragment CONFIG_CGROUP_BPF=y
CONFIG_CGROUP_BPF=y is required for test_dev_cgroup test case.

Signed-off-by: Naresh Kamboju <naresh.kamboju@linaro.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2017-12-12 02:32:45 +01:00
Daniel Borkmann
97c5058922 Merge branch 'bpf-bpftool-makefile-cleanups'
Quentin Monnet says:

====================
First patch of this series cleans up the two Makefiles (Makefile and
Documentation/Makefile) and make their contents more consistent.

The second one add "uninstall" and "doc-uninstall" targets, to remove
files previously installed on the system with "install" and "doc-install"
targets.
====================

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2017-12-08 20:16:22 +01:00
Quentin Monnet
d32442485d tools: bpftool: create "uninstall", "doc-uninstall" make targets
Create two targets to remove executable and documentation that would
have been previously installed with `make install` and `make
doc-install`.

Also create a "QUIET_UNINST" helper in tools/scripts/Makefile.include.

Do not attempt to remove directories /usr/local/sbin and
/usr/share/bash-completions/completions, even if they are empty, as
those specific directories probably already existed on the system before
we installed the program, and we do not wish to break other makefiles
that might assume their existence. Do remvoe /usr/local/share/man/man8
if empty however, as this directory does not seem to exist by default.

Signed-off-by: Quentin Monnet <quentin.monnet@netronome.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2017-12-08 20:14:16 +01:00
Quentin Monnet
658e85aa4f tools: bpftool: harmonise Makefile and Documentation/Makefile
Several minor fixes and harmonisation items for Makefiles:

* Use the same mechanism for verbose/non-verbose output in two files
  ("$(Q)"), for all commands.
* Use calls to "QUIET_INSTALL" and equivalent in Makefile. In
  particular, use "call(descend, ...)" instead of "make -C" to run
  documentation targets.
* Add a "doc-clean" target, aligned on "doc" and "doc-install".
* Make "install" target in Makefile depend on "bpftool".
* Remove condition on DESTDIR to initialise prefix in doc Makefile.
* Remove modification of VPATH based on OUTPUT, it is unused.
* Formatting: harmonise spaces around equal signs.
* Make install path for man pages /usr/local/man instead of
  /usr/local/share/man (respects the Makefile conventions, and the
  latter is usually a symbolic link to the former anyway).
* Do not erase prefix if set by user in bpftool Makefile.
* Fix install target for bpftool: append DESTDIR to install path.

Signed-off-by: Quentin Monnet <quentin.monnet@netronome.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2017-12-08 20:14:02 +01:00
David S. Miller
62cd277039 Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next
Alexei Starovoitov says:

====================
pull-request: bpf-next 2017-12-07

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

The main changes are:

1) Detailed documentation of BPF development process from Daniel.

2) Addition of is_fullsock, snd_cwnd and srtt_us fields to bpf_sock_ops
   from Lawrence.

3) Minor follow up for bpf_skb_set_tunnel_key() from William.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2017-12-08 10:48:25 -05:00
Jason Wang
124da8f611 tuntap: fix possible deadlock when fail to register netdev
Private destructor could be called when register_netdev() fail with
rtnl lock held. This will lead deadlock in tun_free_netdev() who tries
to hold rtnl_lock. Fixing this by switching to use spinlock to
synchronize.

Fixes: 96f8406162 ("tun: add eBPF based queue selection method")
Reported-by: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Willem de Bruijn <willemb@google.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-12-08 10:44:27 -05:00
David S. Miller
66c5c5b566 Merge branch 'smc-fixes-next'
Ursula Braun says:

====================
smc: fixes 2017-12-07

here are some smc-patches. The initial 4 patches are cleanups.
Patch 5 gets rid of ib_post_sends in tasklet context to avoid peer drops due
to out-of-order receivals.
Patch 6 makes sure, the Linux SMC code understands variable sized CLC proposal
messages built according to RFC7609.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2017-12-07 15:03:13 -05:00
Ursula Braun
e7b7a64a84 smc: support variable CLC proposal messages
According to RFC7609 [1] the CLC proposal message contains an area of
unknown length for future growth. Additionally it may contain up to
8 IPv6 prefixes. The current version of the SMC-code does not
understand CLC proposal messages using these variable length fields and,
thus, is incompatible with SMC implementations in other operating
systems.

This patch makes sure, SMC understands incoming CLC proposals
* with arbitrary length values for future growth
* with up to 8 IPv6 prefixes

[1] SMC-R Informational RFC: http://www.rfc-editor.org/info/rfc7609

Signed-off-by: Ursula Braun <ubraun@linux.vnet.ibm.com>
Reviewed-by: Hans Wippel <hwippel@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-12-07 15:03:12 -05:00
Ursula Braun
6b5771aa3c smc: no consumer update in tasklet context
The SMC protocol requires to send a separate consumer cursor update,
if it cannot be piggybacked to updates of the producer cursor.
When receiving a blocked signal from the sender, this update is sent
already in tasklet context. In addition consumer cursor updates are
sent after data receival.
Sending of cursor updates is controlled by sequence numbers.
Assuming receiving stray messages the receiver drops updates with older
sequence numbers than an already received cursor update with a higher
sequence number.
Sending consumer cursor updates in tasklet context may result in
wrong order sends and its corresponding drops at the receiver. Since
it is sufficient to send consumer cursor updates once the data is
received, this patch gets rid of the consumer cursor update in tasklet
context to guarantee in-sequence arrival of cursor updates.

Signed-off-by: Ursula Braun <ubraun@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-12-07 15:03:12 -05:00
Ursula Braun
71c125c3f2 smc: cleanup close checking during data receival
When waiting for data to be received it must be checked if the
peer signals shutdown. The SMC code uses two different checks
for this purpose, even though just one check is sufficient.
This patch removes the superfluous test for SOCK_DONE.

Signed-off-by: Ursula Braun <ubraun@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-12-07 15:03:12 -05:00
Ursula Braun
4bd3e7fbfa smc: no update for unused sk_write_pending
The smc code never checks the sk_write_pending sock field.
Thus there is no need to update it.

Signed-off-by: Ursula Braun <ubraun@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-12-07 15:03:12 -05:00
Ursula Braun
0c9f1515aa smc: improve smc_clc_send_decline() error handling
Let smc_clc_send_decline() return with an error, if the amount
sent is smaller than the length of an smc decline message.

Signed-off-by: Ursula Braun <ubraun@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-12-07 15:03:12 -05:00
Ursula Braun
a8ae890b9c smc: make smc_close_active_abort() static
smc_close_active_abort() is used in smc_close.c only.
Make it static.

Signed-off-by: Ursula Braun <ubraun@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-12-07 15:03:12 -05:00
Florian Fainelli
2a93c1a365 net: dsa: Allow compiling out legacy support
Introduce a configuration option: CONFIG_NET_DSA_LEGACY allowing to compile out
support for the old platform device and Device Tree binding registration.
Support for these configurations is scheduled to be removed in 4.17.

Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-12-07 14:14:54 -05:00
Michael Chan
a8168b6cee bnxt_en: Don't print "Link speed -1 no longer supported" messages.
On some dual port NICs, the 2 ports have to be configured with compatible
link speeds.  Under some conditions, a port's configured speed may no
longer be supported.  The firmware will send a message to the driver
when this happens.

Improve this logic that prints out the warning by only printing it if
we can determine the link speed that is no longer supported.  If the
speed is unknown or it is in autoneg mode, skip the warning message.

Reported-by: Thomas Bogendoerfer <tbogendoerfer@suse.de>
Signed-off-by: Michael Chan <michael.chan@broadcom.com>
Tested-by: Thomas Bogendoerfer <tbogendoerfer@suse.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-12-07 13:35:56 -05:00
Alexei Starovoitov
47adc5b07c Merge branch 'bpf-devel-doc'
Daniel Borkmann says:

====================
Few BPF doc updates

Two changes, i) add BPF trees into maintainers file, and ii) add
a BPF doc around the development process, similarly as we have
with netdev FAQ, but just describing BPF specifics. Thanks!
====================

Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2017-12-06 14:35:04 -08:00
Daniel Borkmann
34f15bf31e bpf, doc: add faq about bpf development process
In the same spirit of netdev FAQ, start a BPF FAQ as a collection
of expectations and/or workflow details in the context of BPF patch
processing.

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2017-12-06 14:32:42 -08:00
Daniel Borkmann
5e01929ff0 bpf, doc: add bpf trees and tps to maintainers entry
i) Add the bpf and bpf-next trees to the maintainers entry
   so they can be found easily and picked up by test bots
   etc that would integrate all trees from maintainers file.
   Suggested by Stephen while integrating the trees into
   linux-next.

ii) Add the two headers defining BPF/XDP tracepoints to the
    list of files as well.

Suggested-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2017-12-06 14:32:42 -08:00
Gao Feng
24e5992a6b ipvlan: Eliminate duplicated codes with existing function
The recv flow of ipvlan l2 mode performs as same as l3 mode for
non-multicast packet, so use the existing func ipvlan_handle_mode_l3
instead of these duplicated statements in non-multicast case.

Signed-off-by: Gao Feng <gfree.wind@vip.163.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-12-06 15:15:29 -05:00
Jiri Pirko
9454d9307e mlxsw: spectrum: handle NETIF_F_HW_TC changes correctly
Currently, whenever the NETIF_F_HW_TC feature changes, we silently
always allow it, but we actually do not disable the flows in HW
on disable. That breaks user's expectations. So just forbid
the feature disable in case there are any filters offloaded.

Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Reviewed-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-12-06 15:11:17 -05:00
Willem de Bruijn
cc166427dc tun: avoid unnecessary READ_ONCE in tun_net_xmit
The statement no longer serves a purpose.

Commit fa35864e0b ("tuntap: Fix for a race in accessing numqueues")
added the ACCESS_ONCE to avoid a race condition with skb_queue_len.

Commit 436accebb5 ("tuntap: remove unnecessary sk_receive_queue
length check during xmit") removed the affected skb_queue_len check.

Commit 96f8406162 ("tun: add eBPF based queue selection method")
split the function, reading the field a second time in the callee.
The temp variable is now only read once, so just remove it.

Signed-off-by: Willem de Bruijn <willemb@google.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-12-06 15:09:13 -05:00
Prashant Bhole
d9b8693783 rds: debug: fix null check on static array
t_name cannot be NULL since it is an array field of a struct.
Replacing null check on static array with string length check using
strnlen()

Signed-off-by: Prashant Bhole <bhole_prashant_q7@lab.ntt.co.jp>
Acked-by: Sowmini Varadhan <sowmini.varadhan@oracle.com>
Acked-by: Santosh Shilimkar <santosh.shilimkar@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-12-06 15:02:48 -05:00
Cong Wang
4bee00eb25 act_mirred: get rid of mirred_list_lock spinlock
TC actions are no longer freed in RCU callbacks and we should
always have RTNL lock, so this spinlock is no longer needed.

Cc: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Jiri Pirko <jiri@mellanox.com>
Cc: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Acked-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-12-06 14:50:13 -05:00
Cong Wang
9f8a739e72 act_mirred: get rid of tcfm_ifindex from struct tcf_mirred
tcfm_dev always points to the correct netdev and we already
hold a refcnt, so no need to use tcfm_ifindex to lookup again.

If we would support moving target netdev across netns, using
pointer would be better than ifindex.

This also fixes dumping obsolete ifindex, now after the
target device is gone we just dump 0 as ifindex.

Cc: Jiri Pirko <jiri@mellanox.com>
Cc: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Acked-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-12-06 14:50:13 -05:00
David S. Miller
3a9ab39328 Merge branch 'ipv6-add-ip6erspan-collect_md-mode'
William Tu says:

====================
ipv6: add ip6erspan collect_md mode

Similar to erspan collect_md mode in ipv4, the first patch adds
support for ip6erspan collect metadata mode.  The second patch
adds the test case using bpf_skb_[gs]et_tunnel_key helpers.

The corresponding iproute2 patch:
https://marc.info/?l=linux-netdev&m=151251545410047&w=2
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2017-12-06 14:45:29 -05:00