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505 Commits (b0b04fc49e3b97a6039b9b658798efdcda71478d)

Author SHA1 Message Date
Alexei Starovoitov cc2b14d510 bpf: teach verifier to recognize zero initialized stack
programs with function calls are often passing various
pointers via stack. When all calls are inlined llvm
flattens stack accesses and optimizes away extra branches.
When functions are not inlined it becomes the job of
the verifier to recognize zero initialized stack to avoid
exploring paths that program will not take.
The following program would fail otherwise:

ptr = &buffer_on_stack;
*ptr = 0;
...
func_call(.., ptr, ...) {
  if (..)
    *ptr = bpf_map_lookup();
}
...
if (*ptr != 0) {
  // Access (*ptr)->field is valid.
  // Without stack_zero tracking such (*ptr)->field access
  // will be rejected
}

since stack slots are no longer uniform invalid | spill | misc
add liveness marking to all slots, but do it in 8 byte chunks.
So if nothing was read or written in [fp-16, fp-9] range
it will be marked as LIVE_NONE.
If any byte in that range was read, it will be marked LIVE_READ
and stacksafe() check will perform byte-by-byte verification.
If all bytes in the range were written the slot will be
marked as LIVE_WRITTEN.
This significantly speeds up state equality comparison
and reduces total number of states processed.

                    before   after
bpf_lb-DLB_L3.o       2051    2003
bpf_lb-DLB_L4.o       3287    3164
bpf_lb-DUNKNOWN.o     1080    1080
bpf_lxc-DDROP_ALL.o   24980   12361
bpf_lxc-DUNKNOWN.o    34308   16605
bpf_netdev.o          15404   10962
bpf_overlay.o         7191    6679

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
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
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
David S. Miller 7cda4cee13 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Small overlapping change conflict ('net' changed a line,
'net-next' added a line right afterwards) in flexcan.c

Signed-off-by: David S. Miller <davem@davemloft.net>
2017-12-05 10:44:19 -05:00
Alexei Starovoitov 914cb781ee bpf: cleanup register_is_null()
don't pass large struct bpf_reg_state by value.
Instead pass it by pointer.

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>
2017-12-01 11:25:10 +01:00
Alexei Starovoitov 3bf15921c5 bpf: improve JEQ/JNE path walking
verifier knows how to trim paths that are known not to be
taken at run-time when register containing run-time constant
is compared with another constant.
It was done only for JEQ comparison.
Extend it to include JNE as well.
More cases can be added in the future.

                     before  after
bpf_lb-DLB_L3.o       2270    2051
bpf_lb-DLB_L4.o       3682    3287
bpf_lb-DUNKNOWN.o     1110    1080
bpf_lxc-DDROP_ALL.o   27876   24980
bpf_lxc-DUNKNOWN.o    38780   34308
bpf_netdev.o          16937   15404
bpf_overlay.o         7929    7191

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>
2017-12-01 11:25:10 +01:00
Alexei Starovoitov 2f18f62ee1 bpf: improve verifier liveness marks
registers with pointers filled from stack were missing live_written marks
which caused liveness propagation to unnecessary mark more registers as
live_read and miss state pruning opportunities later on.

                     before  after
bpf_lb-DLB_L3.o       2285   2270
bpf_lb-DLB_L4.o       3723   3682
bpf_lb-DUNKNOWN.o     1110   1110
bpf_lxc-DDROP_ALL.o   27954  27876
bpf_lxc-DUNKNOWN.o    38954  38780
bpf_netdev.o          16943  16937
bpf_overlay.o         7929   7929

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>
2017-12-01 11:25:10 +01:00
Alexei Starovoitov 19ceb4178d bpf: don't mark FP reg as uninit
when verifier hits an internal bug don't mark register R10==FP as uninit,
since it's read only register and it's not technically correct to let
verifier run further, since it may assume that R10 has valid auxiliary state.

While developing subsequent patches this issue was discovered,
though the code eventually changed that aux reg state doesn't have
pointers any more it is still safer to avoid clearing readonly register.

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>
2017-12-01 11:25:10 +01:00
Alexei Starovoitov 4e92024a48 bpf: print liveness info to verifier log
let verifier print register and stack liveness information
into verifier log

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>
2017-12-01 11:25:10 +01:00
Alexei Starovoitov 12a3cc8424 bpf: fix stack state printing in verifier log
fix incorrect stack state prints in print_verifier_state()

Fixes: 638f5b90d4 ("bpf: reduce verifier memory consumption")
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>
2017-12-01 11:25:10 +01:00
Yonghong Song c8c088ba0e bpf: set maximum number of attached progs to 64 for a single perf tp
cgropu+bpf prog array has a maximum number of 64 programs.
Let us apply the same limit here.

Fixes: e87c6bc385 ("bpf: permit multiple bpf attachments for a single perf event")
Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2017-12-01 02:56:10 +01:00
Jakub Kicinski a39e17b2d8 bpf: offload: add a license header
I forgot to add a license on kernel/bpf/offload.c.  Luckily I'm
still the only author so make it explicitly GPLv2.

Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Simon Horman <simon.horman@netronome.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2017-11-27 22:24:51 +01:00
Alexei Starovoitov c131187db2 bpf: fix branch pruning logic
when the verifier detects that register contains a runtime constant
and it's compared with another constant it will prune exploration
of the branch that is guaranteed not to be taken at runtime.
This is all correct, but malicious program may be constructed
in such a way that it always has a constant comparison and
the other branch is never taken under any conditions.
In this case such path through the program will not be explored
by the verifier. It won't be taken at run-time either, but since
all instructions are JITed the malicious program may cause JITs
to complain about using reserved fields, etc.
To fix the issue we have to track the instructions explored by
the verifier and sanitize instructions that are dead at run time
with NOPs. We cannot reject such dead code, since llvm generates
it for valid C code, since it doesn't do as much data flow
analysis as the verifier does.

Fixes: 17a5267067 ("bpf: verifier (add verifier core)")
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2017-11-23 10:56:35 +01:00
Gianluca Borello db1ac4964f bpf: introduce ARG_PTR_TO_MEM_OR_NULL
With the current ARG_PTR_TO_MEM/ARG_PTR_TO_UNINIT_MEM semantics, an helper
argument can be NULL when the next argument type is ARG_CONST_SIZE_OR_ZERO
and the verifier can prove the value of this next argument is 0. However,
most helpers are just interested in handling <!NULL, 0>, so forcing them to
deal with <NULL, 0> makes the implementation of those helpers more
complicated for no apparent benefits, requiring them to explicitly handle
those corner cases with checks that bpf programs could start relying upon,
preventing the possibility of removing them later.

Solve this by making ARG_PTR_TO_MEM/ARG_PTR_TO_UNINIT_MEM never accept NULL
even when ARG_CONST_SIZE_OR_ZERO is set, and introduce a new argument type
ARG_PTR_TO_MEM_OR_NULL to explicitly deal with the NULL case.

Currently, the only helper that needs this is bpf_csum_diff_proto(), so
change arg1 and arg3 to this new type as well.

Also add a new battery of tests that explicitly test the
!ARG_PTR_TO_MEM_OR_NULL combination: all the current ones testing the
various <NULL, 0> variations are focused on bpf_csum_diff, so cover also
other helpers.

Signed-off-by: Gianluca Borello <g.borello@gmail.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2017-11-22 21:40:54 +01:00
Jakub Kicinski 1ee640095f bpf: revert report offload info to user space
This reverts commit bd601b6ada ("bpf: report offload info to user
space").  The ifindex by itself is not sufficient, we should provide
information on which network namespace this ifindex belongs to.
After considering some options we concluded that it's best to just
remove this API for now, and rework it in -next.

Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2017-11-21 00:37:35 +01:00
Jakub Kicinski 62c71b45e8 bpf: offload: ignore namespace moves
We are currently destroying the device offload state when device
moves to another net namespace.  This doesn't break with current
NFP code, because offload state is not used on program removal,
but it's not correct behaviour.

Ignore the device unregister notifications on namespace move.

Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2017-11-21 00:37:35 +01:00
Jakub Kicinski 479321e9c3 bpf: turn bpf_prog_get_type() into a wrapper
bpf_prog_get_type() is identical to bpf_prog_get_type_dev(),
with false passed as attach_drv.  Instead of keeping it as
an exported symbol turn it into static inline wrapper.

Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2017-11-21 00:37:35 +01:00
Jakub Kicinski 288b3de55a bpf: offload: move offload device validation out to the drivers
With TC shared block changes we can't depend on correct netdev
pointer being available in cls_bpf.  Move the device validation
to the driver.  Core will only make sure that offloaded programs
are always attached in the driver (or in HW by the driver).  We
trust that drivers which implement offload callbacks will perform
necessary checks.

Moving the checks to the driver is generally a useful thing,
in practice the check should be against a switchdev instance,
not a netdev, given that most ASICs will probably allow using
the same program on many ports.

Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2017-11-21 00:37:35 +01:00
Jakub Kicinski 1f6f4cb7ba bpf: offload: rename the ifindex field
bpf_target_prog seems long and clunky, rename it to prog_ifindex.
We don't want to call this field just ifindex, because maps
may need a similar field in the future and bpf_attr members for
programs and maps are unnamed.

Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2017-11-21 00:37:35 +01:00
Jakub Kicinski 649f11dcd1 bpf: offload: limit offload to cls_bpf and xdp programs only
We are currently only allowing attachment of device-bound
cls_bpf and XDP programs.  Make this restriction explicit in
the BPF offload code.  This way we can potentially reuse the
ifindex field in the future.

Since XDP and cls_bpf programs can only be loaded by admin,
we can drop the explicit capability check from offload code.

Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2017-11-21 00:37:35 +01:00
Jakub Kicinski 13a9c48a85 bpf: offload: add comment warning developers about double destroy
Offload state may get destroyed either because the device for which
it was constructed is going away, or because the refcount of bpf
program itself has reached 0.  In both of those cases we will call
__bpf_prog_offload_destroy() to unlink the offload from the device.
We may in fact call it twice, which works just fine, but we should
make clear this is intended and caution others trying to extend the
function.

Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2017-11-21 00:37:35 +01:00
Linus Torvalds 7c225c69f8 Merge branch 'akpm' (patches from Andrew)
Merge updates from Andrew Morton:

 - a few misc bits

 - ocfs2 updates

 - almost all of MM

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (131 commits)
  memory hotplug: fix comments when adding section
  mm: make alloc_node_mem_map a void call if we don't have CONFIG_FLAT_NODE_MEM_MAP
  mm: simplify nodemask printing
  mm,oom_reaper: remove pointless kthread_run() error check
  mm/page_ext.c: check if page_ext is not prepared
  writeback: remove unused function parameter
  mm: do not rely on preempt_count in print_vma_addr
  mm, sparse: do not swamp log with huge vmemmap allocation failures
  mm/hmm: remove redundant variable align_end
  mm/list_lru.c: mark expected switch fall-through
  mm/shmem.c: mark expected switch fall-through
  mm/page_alloc.c: broken deferred calculation
  mm: don't warn about allocations which stall for too long
  fs: fuse: account fuse_inode slab memory as reclaimable
  mm, page_alloc: fix potential false positive in __zone_watermark_ok
  mm: mlock: remove lru_add_drain_all()
  mm, sysctl: make NUMA stats configurable
  shmem: convert shmem_init_inodecache() to void
  Unify migrate_pages and move_pages access checks
  mm, pagevec: rename pagevec drained field
  ...
2017-11-15 19:42:40 -08:00
Levin, Alexander (Sasha Levin) 4950276672 kmemcheck: remove annotations
Patch series "kmemcheck: kill kmemcheck", v2.

As discussed at LSF/MM, kill kmemcheck.

KASan is a replacement that is able to work without the limitation of
kmemcheck (single CPU, slow).  KASan is already upstream.

We are also not aware of any users of kmemcheck (or users who don't
consider KASan as a suitable replacement).

The only objection was that since KASAN wasn't supported by all GCC
versions provided by distros at that time we should hold off for 2
years, and try again.

Now that 2 years have passed, and all distros provide gcc that supports
KASAN, kill kmemcheck again for the very same reasons.

This patch (of 4):

Remove kmemcheck annotations, and calls to kmemcheck from the kernel.

[alexander.levin@verizon.com: correctly remove kmemcheck call from dma_map_sg_attrs]
  Link: http://lkml.kernel.org/r/20171012192151.26531-1-alexander.levin@verizon.com
Link: http://lkml.kernel.org/r/20171007030159.22241-2-alexander.levin@verizon.com
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Tim Hansen <devtimhansen@gmail.com>
Cc: Vegard Nossum <vegardno@ifi.uio.no>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-11-15 18:21:04 -08:00
Eric Dumazet 89ad2fa3f0 bpf: fix lockdep splat
pcpu_freelist_pop() needs the same lockdep awareness than
pcpu_freelist_populate() to avoid a false positive.

 [ INFO: SOFTIRQ-safe -> SOFTIRQ-unsafe lock order detected ]

 switchto-defaul/12508 [HC0[0]:SC0[6]:HE0:SE0] is trying to acquire:
  (&htab->buckets[i].lock){......}, at: [<ffffffff9dc099cb>] __htab_percpu_map_update_elem+0x1cb/0x300

 and this task is already holding:
  (dev_queue->dev->qdisc_class ?: &qdisc_tx_lock#2){+.-...}, at: [<ffffffff9e135848>] __dev_queue_xmit+0
x868/0x1240
 which would create a new lock dependency:
  (dev_queue->dev->qdisc_class ?: &qdisc_tx_lock#2){+.-...} -> (&htab->buckets[i].lock){......}

 but this new dependency connects a SOFTIRQ-irq-safe lock:
  (dev_queue->dev->qdisc_class ?: &qdisc_tx_lock#2){+.-...}
 ... which became SOFTIRQ-irq-safe at:
   [<ffffffff9db5931b>] __lock_acquire+0x42b/0x1f10
   [<ffffffff9db5b32c>] lock_acquire+0xbc/0x1b0
   [<ffffffff9da05e38>] _raw_spin_lock+0x38/0x50
   [<ffffffff9e135848>] __dev_queue_xmit+0x868/0x1240
   [<ffffffff9e136240>] dev_queue_xmit+0x10/0x20
   [<ffffffff9e1965d9>] ip_finish_output2+0x439/0x590
   [<ffffffff9e197410>] ip_finish_output+0x150/0x2f0
   [<ffffffff9e19886d>] ip_output+0x7d/0x260
   [<ffffffff9e19789e>] ip_local_out+0x5e/0xe0
   [<ffffffff9e197b25>] ip_queue_xmit+0x205/0x620
   [<ffffffff9e1b8398>] tcp_transmit_skb+0x5a8/0xcb0
   [<ffffffff9e1ba152>] tcp_write_xmit+0x242/0x1070
   [<ffffffff9e1baffc>] __tcp_push_pending_frames+0x3c/0xf0
   [<ffffffff9e1b3472>] tcp_rcv_established+0x312/0x700
   [<ffffffff9e1c1acc>] tcp_v4_do_rcv+0x11c/0x200
   [<ffffffff9e1c3dc2>] tcp_v4_rcv+0xaa2/0xc30
   [<ffffffff9e191107>] ip_local_deliver_finish+0xa7/0x240
   [<ffffffff9e191a36>] ip_local_deliver+0x66/0x200
   [<ffffffff9e19137d>] ip_rcv_finish+0xdd/0x560
   [<ffffffff9e191e65>] ip_rcv+0x295/0x510
   [<ffffffff9e12ff88>] __netif_receive_skb_core+0x988/0x1020
   [<ffffffff9e130641>] __netif_receive_skb+0x21/0x70
   [<ffffffff9e1306ff>] process_backlog+0x6f/0x230
   [<ffffffff9e132129>] net_rx_action+0x229/0x420
   [<ffffffff9da07ee8>] __do_softirq+0xd8/0x43d
   [<ffffffff9e282bcc>] do_softirq_own_stack+0x1c/0x30
   [<ffffffff9dafc2f5>] do_softirq+0x55/0x60
   [<ffffffff9dafc3a8>] __local_bh_enable_ip+0xa8/0xb0
   [<ffffffff9db4c727>] cpu_startup_entry+0x1c7/0x500
   [<ffffffff9daab333>] start_secondary+0x113/0x140

 to a SOFTIRQ-irq-unsafe lock:
  (&head->lock){+.+...}
 ... which became SOFTIRQ-irq-unsafe at:
 ...  [<ffffffff9db5971f>] __lock_acquire+0x82f/0x1f10
   [<ffffffff9db5b32c>] lock_acquire+0xbc/0x1b0
   [<ffffffff9da05e38>] _raw_spin_lock+0x38/0x50
   [<ffffffff9dc0b7fa>] pcpu_freelist_pop+0x7a/0xb0
   [<ffffffff9dc08b2c>] htab_map_alloc+0x50c/0x5f0
   [<ffffffff9dc00dc5>] SyS_bpf+0x265/0x1200
   [<ffffffff9e28195f>] entry_SYSCALL_64_fastpath+0x12/0x17

 other info that might help us debug this:

 Chain exists of:
   dev_queue->dev->qdisc_class ?: &qdisc_tx_lock#2 --> &htab->buckets[i].lock --> &head->lock

  Possible interrupt unsafe locking scenario:

        CPU0                    CPU1
        ----                    ----
   lock(&head->lock);
                                local_irq_disable();
                                lock(dev_queue->dev->qdisc_class ?: &qdisc_tx_lock#2);
                                lock(&htab->buckets[i].lock);
   <Interrupt>
     lock(dev_queue->dev->qdisc_class ?: &qdisc_tx_lock#2);

  *** DEADLOCK ***

Fixes: e19494edab ("bpf: introduce percpu_freelist")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-15 19:46:32 +09:00
Yonghong Song 9fd29c08e5 bpf: improve verifier ARG_CONST_SIZE_OR_ZERO semantics
For helpers, the argument type ARG_CONST_SIZE_OR_ZERO permits the
access size to be 0 when accessing the previous argument (arg).
Right now, it requires the arg needs to be NULL when size passed
is 0 or could be 0. It also requires a non-NULL arg when the size
is proved to be non-0.

This patch changes verifier ARG_CONST_SIZE_OR_ZERO behavior
such that for size-0 or possible size-0, it is not required
the arg equal to NULL.

There are a couple of reasons for this semantics change, and
all of them intends to simplify user bpf programs which
may improve user experience and/or increase chances of
verifier acceptance. Together with the next patch which
changes bpf_probe_read arg2 type from ARG_CONST_SIZE to
ARG_CONST_SIZE_OR_ZERO, the following two examples, which
fail the verifier currently, are able to get verifier acceptance.

Example 1:
   unsigned long len = pend - pstart;
   len = len > MAX_PAYLOAD_LEN ? MAX_PAYLOAD_LEN : len;
   len &= MAX_PAYLOAD_LEN;
   bpf_probe_read(data->payload, len, pstart);

It does not have test for "len > 0" and it failed the verifier.
Users may not be aware that they have to add this test.
Converting the bpf_probe_read helper to have
ARG_CONST_SIZE_OR_ZERO helps the above code get
verifier acceptance.

Example 2:
  Here is one example where llvm "messed up" the code and
  the verifier fails.

......
   unsigned long len = pend - pstart;
   if (len > 0 && len <= MAX_PAYLOAD_LEN)
     bpf_probe_read(data->payload, len, pstart);
......

The compiler generates the following code and verifier fails:
......
39: (79) r2 = *(u64 *)(r10 -16)
40: (1f) r2 -= r8
41: (bf) r1 = r2
42: (07) r1 += -1
43: (25) if r1 > 0xffe goto pc+3
  R0=inv(id=0) R1=inv(id=0,umax_value=4094,var_off=(0x0; 0xfff))
  R2=inv(id=0) R6=map_value(id=0,off=0,ks=4,vs=4095,imm=0) R7=inv(id=0)
  R8=inv(id=0) R9=inv0 R10=fp0
44: (bf) r1 = r6
45: (bf) r3 = r8
46: (85) call bpf_probe_read#45
R2 min value is negative, either use unsigned or 'var &= const'
......

The compiler optimization is correct. If r1 = 0,
r1 - 1 = 0xffffffffffffffff > 0xffe.  If r1 != 0, r1 - 1 will not wrap.
r1 > 0xffe at insn #43 can actually capture
both "r1 > 0" and "len <= MAX_PAYLOAD_LEN".
This however causes an issue in verifier as the value range of arg2
"r2" does not properly get refined and lead to verification failure.

Relaxing bpf_prog_read arg2 from ARG_CONST_SIZE to ARG_CONST_SIZE_OR_ZERO
allows the following simplied code:
   unsigned long len = pend - pstart;
   if (len <= MAX_PAYLOAD_LEN)
     bpf_probe_read(data->payload, len, pstart);

The llvm compiler will generate less complex code and the
verifier is able to verify that the program is okay.

Signed-off-by: Yonghong Song <yhs@fb.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-14 16:20:03 +09:00
David S. Miller f3edacbd69 bpf: Revert bpf_overrid_function() helper changes.
NACK'd by x86 maintainer.

Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-11 18:24:55 +09:00
Josef Bacik dd0bb688ea 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>
Signed-off-by: Josef Bacik <jbacik@fb.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-11 12:18:05 +09:00
Ingo Molnar 15bcdc9477 Merge branch 'linus' into perf/core, to fix conflicts
Conflicts:
	tools/perf/arch/arm/annotate/instructions.c
	tools/perf/arch/arm64/annotate/instructions.c
	tools/perf/arch/powerpc/annotate/instructions.c
	tools/perf/arch/s390/annotate/instructions.c
	tools/perf/arch/x86/tests/intel-cqm.c
	tools/perf/ui/tui/progress.c
	tools/perf/util/zlib.c

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-11-07 10:30:18 +01:00
Roman Gushchin ebc614f687 bpf, cgroup: implement eBPF-based device controller for cgroup v2
Cgroup v2 lacks the device controller, provided by cgroup v1.
This patch adds a new eBPF program type, which in combination
of previously added ability to attach multiple eBPF programs
to a cgroup, will provide a similar functionality, but with some
additional flexibility.

This patch introduces a BPF_PROG_TYPE_CGROUP_DEVICE program type.
A program takes major and minor device numbers, device type
(block/character) and access type (mknod/read/write) as parameters
and returns an integer which defines if the operation should be
allowed or terminated with -EPERM.

Signed-off-by: Roman Gushchin <guro@fb.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Tejun Heo <tj@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-05 23:26:51 +09:00
Jakub Kicinski b37a530613 bpf: remove old offload/analyzer
Thanks to the ability to load a program for a specific device,
running verifier twice is no longer needed.

Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-05 22:26:20 +09:00
Jakub Kicinski 6c8dfe21c4 cls_bpf: allow attaching programs loaded for specific device
If TC program is loaded with skip_sw flag, we should allow
the device-specific programs to be accepted.

Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Simon Horman <simon.horman@netronome.com>
Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-05 22:26:19 +09:00
Jakub Kicinski 248f346ffe xdp: allow attaching programs loaded for specific device
Pass the netdev pointer to bpf_prog_get_type().  This way
BPF code can decide whether the device matches what the
code was loaded/translated for.

Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Simon Horman <simon.horman@netronome.com>
Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-05 22:26:19 +09:00
Jakub Kicinski bd601b6ada bpf: report offload info to user space
Extend struct bpf_prog_info to contain information about program
being bound to a device.  Since the netdev may get destroyed while
program still exists we need a flag to indicate the program is
loaded for a device, even if the device is gone.

Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Simon Horman <simon.horman@netronome.com>
Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-05 22:26:18 +09:00
Jakub Kicinski ab3f0063c4 bpf: offload: add infrastructure for loading programs for a specific netdev
The fact that we don't know which device the program is going
to be used on is quite limiting in current eBPF infrastructure.
We have to reverse or limit the changes which kernel makes to
the loaded bytecode if we want it to be offloaded to a networking
device.  We also have to invent new APIs for debugging and
troubleshooting support.

Make it possible to load programs for a specific netdev.  This
helps us to bring the debug information closer to the core
eBPF infrastructure (e.g. we will be able to reuse the verifer
log in device JIT).  It allows device JITs to perform translation
on the original bytecode.

__bpf_prog_get() when called to get a reference for an attachment
point will now refuse to give it if program has a device assigned.
Following patches will add a version of that function which passes
the expected netdev in. @type argument in __bpf_prog_get() is
renamed to attach_type to make it clearer that it's only set on
attachment.

All calls to ndo_bpf are protected by rtnl, only verifier callbacks
are not.  We need a wait queue to make sure netdev doesn't get
destroyed while verifier is still running and calling its driver.

Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Simon Horman <simon.horman@netronome.com>
Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-05 22:26:18 +09:00
David S. Miller 2a171788ba Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Files removed in 'net-next' had their license header updated
in 'net'.  We take the remove from 'net-next'.

Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-04 09:26:51 +09:00
Craig Gallek 8c01c4f896 bpf: fix verifier NULL pointer dereference
do_check() can fail early without allocating env->cur_state under
memory pressure.  Syzkaller found the stack below on the linux-next
tree because of this.

  kasan: CONFIG_KASAN_INLINE enabled
  kasan: GPF could be caused by NULL-ptr deref or user memory access
  general protection fault: 0000 [#1] SMP KASAN
  Dumping ftrace buffer:
     (ftrace buffer empty)
  Modules linked in:
  CPU: 1 PID: 27062 Comm: syz-executor5 Not tainted 4.14.0-rc7+ #106
  Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
  task: ffff8801c2c74700 task.stack: ffff8801c3e28000
  RIP: 0010:free_verifier_state kernel/bpf/verifier.c:347 [inline]
  RIP: 0010:bpf_check+0xcf4/0x19c0 kernel/bpf/verifier.c:4533
  RSP: 0018:ffff8801c3e2f5c8 EFLAGS: 00010202
  RAX: dffffc0000000000 RBX: 00000000fffffff4 RCX: 0000000000000000
  RDX: 0000000000000070 RSI: ffffffff817d5aa9 RDI: 0000000000000380
  RBP: ffff8801c3e2f668 R08: 0000000000000000 R09: 1ffff100387c5d9f
  R10: 00000000218c4e80 R11: ffffffff85b34380 R12: ffff8801c4dc6a28
  R13: 0000000000000000 R14: ffff8801c4dc6a00 R15: ffff8801c4dc6a20
  FS:  00007f311079b700(0000) GS:ffff8801db300000(0000) knlGS:0000000000000000
  CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
  CR2: 00000000004d4a24 CR3: 00000001cbcd0000 CR4: 00000000001406e0
  DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
  DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
  Call Trace:
   bpf_prog_load+0xcbb/0x18e0 kernel/bpf/syscall.c:1166
   SYSC_bpf kernel/bpf/syscall.c:1690 [inline]
   SyS_bpf+0xae9/0x4620 kernel/bpf/syscall.c:1652
   entry_SYSCALL_64_fastpath+0x1f/0xbe
  RIP: 0033:0x452869
  RSP: 002b:00007f311079abe8 EFLAGS: 00000212 ORIG_RAX: 0000000000000141
  RAX: ffffffffffffffda RBX: 0000000000758020 RCX: 0000000000452869
  RDX: 0000000000000030 RSI: 0000000020168000 RDI: 0000000000000005
  RBP: 00007f311079aa20 R08: 0000000000000000 R09: 0000000000000000
  R10: 0000000000000000 R11: 0000000000000212 R12: 00000000004b7550
  R13: 00007f311079ab58 R14: 00000000004b7560 R15: 0000000000000000
  Code: df 48 c1 ea 03 80 3c 02 00 0f 85 e6 0b 00 00 4d 8b 6e 20 48 b8 00 00 00 00 00 fc ff df 49 8d bd 80 03 00 00 48 89 fa 48 c1 ea 03 <80> 3c 02 00 0f 85 b6 0b 00 00 49 8b bd 80 03 00 00 e8 d6 0c 26
  RIP: free_verifier_state kernel/bpf/verifier.c:347 [inline] RSP: ffff8801c3e2f5c8
  RIP: bpf_check+0xcf4/0x19c0 kernel/bpf/verifier.c:4533 RSP: ffff8801c3e2f5c8
  ---[ end trace c8d37f339dc64004 ]---

Fixes: 638f5b90d4 ("bpf: reduce verifier memory consumption")
Fixes: 1969db47f8 ("bpf: fix verifier memory leaks")
Signed-off-by: Craig Gallek <kraig@google.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-03 15:49:15 +09:00
Arnd Bergmann eba0c929d1 bpf: fix out-of-bounds access warning in bpf_check
The bpf_verifer_ops array is generated dynamically and may be
empty depending on configuration, which then causes an out
of bounds access:

kernel/bpf/verifier.c: In function 'bpf_check':
kernel/bpf/verifier.c:4320:29: error: array subscript is above array bounds [-Werror=array-bounds]

This adds a check to the start of the function as a workaround.
I would assume that the function is never called in that configuration,
so the warning is probably harmless.

Fixes: 00176a34d9 ("bpf: remove the verifier ops from program structure")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-03 14:20:22 +09:00
Arnd Bergmann 7cce782ef3 bpf: fix link error without CONFIG_NET
I ran into this link error with the latest net-next plus linux-next
trees when networking is disabled:

kernel/bpf/verifier.o:(.rodata+0x2958): undefined reference to `tc_cls_act_analyzer_ops'
kernel/bpf/verifier.o:(.rodata+0x2970): undefined reference to `xdp_analyzer_ops'

It seems that the code was written to deal with varying contents of
the arrray, but the actual #ifdef was missing. Both tc_cls_act_analyzer_ops
and xdp_analyzer_ops are defined in the core networking code, so adding
a check for CONFIG_NET seems appropriate here, and I've verified this with
many randconfig builds

Fixes: 4f9218aaf8 ("bpf: move knowledge about post-translation offsets out of verifier")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-03 14:20:22 +09:00
Linus Torvalds ead751507d License cleanup: add SPDX license identifiers to some files
Many source files in the tree are missing licensing information, which
 makes it harder for compliance tools to determine the correct license.
 
 By default all files without license information are under the default
 license of the kernel, which is GPL version 2.
 
 Update the files which contain no license information with the 'GPL-2.0'
 SPDX license identifier.  The SPDX identifier is a legally binding
 shorthand, which can be used instead of the full boiler plate text.
 
 This patch is based on work done by Thomas Gleixner and Kate Stewart and
 Philippe Ombredanne.
 
 How this work was done:
 
 Patches were generated and checked against linux-4.14-rc6 for a subset of
 the use cases:
  - file had no licensing information it it.
  - file was a */uapi/* one with no licensing information in it,
  - file was a */uapi/* one with existing licensing information,
 
 Further patches will be generated in subsequent months to fix up cases
 where non-standard license headers were used, and references to license
 had to be inferred by heuristics based on keywords.
 
 The analysis to determine which SPDX License Identifier to be applied to
 a file was done in a spreadsheet of side by side results from of the
 output of two independent scanners (ScanCode & Windriver) producing SPDX
 tag:value files created by Philippe Ombredanne.  Philippe prepared the
 base worksheet, and did an initial spot review of a few 1000 files.
 
 The 4.13 kernel was the starting point of the analysis with 60,537 files
 assessed.  Kate Stewart did a file by file comparison of the scanner
 results in the spreadsheet to determine which SPDX license identifier(s)
 to be applied to the file. She confirmed any determination that was not
 immediately clear with lawyers working with the Linux Foundation.
 
 Criteria used to select files for SPDX license identifier tagging was:
  - Files considered eligible had to be source code files.
  - Make and config files were included as candidates if they contained >5
    lines of source
  - File already had some variant of a license header in it (even if <5
    lines).
 
 All documentation files were explicitly excluded.
 
 The following heuristics were used to determine which SPDX license
 identifiers to apply.
 
  - when both scanners couldn't find any license traces, file was
    considered to have no license information in it, and the top level
    COPYING file license applied.
 
    For non */uapi/* files that summary was:
 
    SPDX license identifier                            # files
    ---------------------------------------------------|-------
    GPL-2.0                                              11139
 
    and resulted in the first patch in this series.
 
    If that file was a */uapi/* path one, it was "GPL-2.0 WITH
    Linux-syscall-note" otherwise it was "GPL-2.0".  Results of that was:
 
    SPDX license identifier                            # files
    ---------------------------------------------------|-------
    GPL-2.0 WITH Linux-syscall-note                        930
 
    and resulted in the second patch in this series.
 
  - if a file had some form of licensing information in it, and was one
    of the */uapi/* ones, it was denoted with the Linux-syscall-note if
    any GPL family license was found in the file or had no licensing in
    it (per prior point).  Results summary:
 
    SPDX license identifier                            # files
    ---------------------------------------------------|------
    GPL-2.0 WITH Linux-syscall-note                       270
    GPL-2.0+ WITH Linux-syscall-note                      169
    ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause)    21
    ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause)    17
    LGPL-2.1+ WITH Linux-syscall-note                      15
    GPL-1.0+ WITH Linux-syscall-note                       14
    ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause)    5
    LGPL-2.0+ WITH Linux-syscall-note                       4
    LGPL-2.1 WITH Linux-syscall-note                        3
    ((GPL-2.0 WITH Linux-syscall-note) OR MIT)              3
    ((GPL-2.0 WITH Linux-syscall-note) AND MIT)             1
 
    and that resulted in the third patch in this series.
 
  - when the two scanners agreed on the detected license(s), that became
    the concluded license(s).
 
  - when there was disagreement between the two scanners (one detected a
    license but the other didn't, or they both detected different
    licenses) a manual inspection of the file occurred.
 
  - In most cases a manual inspection of the information in the file
    resulted in a clear resolution of the license that should apply (and
    which scanner probably needed to revisit its heuristics).
 
  - When it was not immediately clear, the license identifier was
    confirmed with lawyers working with the Linux Foundation.
 
  - If there was any question as to the appropriate license identifier,
    the file was flagged for further research and to be revisited later
    in time.
 
 In total, over 70 hours of logged manual review was done on the
 spreadsheet to determine the SPDX license identifiers to apply to the
 source files by Kate, Philippe, Thomas and, in some cases, confirmation
 by lawyers working with the Linux Foundation.
 
 Kate also obtained a third independent scan of the 4.13 code base from
 FOSSology, and compared selected files where the other two scanners
 disagreed against that SPDX file, to see if there was new insights.  The
 Windriver scanner is based on an older version of FOSSology in part, so
 they are related.
 
 Thomas did random spot checks in about 500 files from the spreadsheets
 for the uapi headers and agreed with SPDX license identifier in the
 files he inspected. For the non-uapi files Thomas did random spot checks
 in about 15000 files.
 
 In initial set of patches against 4.14-rc6, 3 files were found to have
 copy/paste license identifier errors, and have been fixed to reflect the
 correct identifier.
 
 Additionally Philippe spent 10 hours this week doing a detailed manual
 inspection and review of the 12,461 patched files from the initial patch
 version early this week with:
  - a full scancode scan run, collecting the matched texts, detected
    license ids and scores
  - reviewing anything where there was a license detected (about 500+
    files) to ensure that the applied SPDX license was correct
  - reviewing anything where there was no detection but the patch license
    was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied
    SPDX license was correct
 
 This produced a worksheet with 20 files needing minor correction.  This
 worksheet was then exported into 3 different .csv files for the
 different types of files to be modified.
 
 These .csv files were then reviewed by Greg.  Thomas wrote a script to
 parse the csv files and add the proper SPDX tag to the file, in the
 format that the file expected.  This script was further refined by Greg
 based on the output to detect more types of files automatically and to
 distinguish between header and source .c files (which need different
 comment types.)  Finally Greg ran the script using the .csv files to
 generate the patches.
 
 Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
 Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com>
 Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'spdx_identifiers-4.14-rc8' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core

Pull initial SPDX identifiers from Greg KH:
 "License cleanup: add SPDX license identifiers to some files

  Many source files in the tree are missing licensing information, which
  makes it harder for compliance tools to determine the correct license.

  By default all files without license information are under the default
  license of the kernel, which is GPL version 2.

  Update the files which contain no license information with the
  'GPL-2.0' SPDX license identifier. The SPDX identifier is a legally
  binding shorthand, which can be used instead of the full boiler plate
  text.

  This patch is based on work done by Thomas Gleixner and Kate Stewart
  and Philippe Ombredanne.

  How this work was done:

  Patches were generated and checked against linux-4.14-rc6 for a subset
  of the use cases:

   - file had no licensing information it it.

   - file was a */uapi/* one with no licensing information in it,

   - file was a */uapi/* one with existing licensing information,

  Further patches will be generated in subsequent months to fix up cases
  where non-standard license headers were used, and references to
  license had to be inferred by heuristics based on keywords.

  The analysis to determine which SPDX License Identifier to be applied
  to a file was done in a spreadsheet of side by side results from of
  the output of two independent scanners (ScanCode & Windriver)
  producing SPDX tag:value files created by Philippe Ombredanne.
  Philippe prepared the base worksheet, and did an initial spot review
  of a few 1000 files.

  The 4.13 kernel was the starting point of the analysis with 60,537
  files assessed. Kate Stewart did a file by file comparison of the
  scanner results in the spreadsheet to determine which SPDX license
  identifier(s) to be applied to the file. She confirmed any
  determination that was not immediately clear with lawyers working with
  the Linux Foundation.

  Criteria used to select files for SPDX license identifier tagging was:

   - Files considered eligible had to be source code files.

   - Make and config files were included as candidates if they contained
     >5 lines of source

   - File already had some variant of a license header in it (even if <5
     lines).

  All documentation files were explicitly excluded.

  The following heuristics were used to determine which SPDX license
  identifiers to apply.

   - when both scanners couldn't find any license traces, file was
     considered to have no license information in it, and the top level
     COPYING file license applied.

     For non */uapi/* files that summary was:

       SPDX license identifier                            # files
       ---------------------------------------------------|-------
       GPL-2.0                                              11139

     and resulted in the first patch in this series.

     If that file was a */uapi/* path one, it was "GPL-2.0 WITH
     Linux-syscall-note" otherwise it was "GPL-2.0". Results of that
     was:

       SPDX license identifier                            # files
       ---------------------------------------------------|-------
       GPL-2.0 WITH Linux-syscall-note                        930

     and resulted in the second patch in this series.

   - if a file had some form of licensing information in it, and was one
     of the */uapi/* ones, it was denoted with the Linux-syscall-note if
     any GPL family license was found in the file or had no licensing in
     it (per prior point). Results summary:

       SPDX license identifier                            # files
       ---------------------------------------------------|------
       GPL-2.0 WITH Linux-syscall-note                       270
       GPL-2.0+ WITH Linux-syscall-note                      169
       ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause)    21
       ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause)    17
       LGPL-2.1+ WITH Linux-syscall-note                      15
       GPL-1.0+ WITH Linux-syscall-note                       14
       ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause)    5
       LGPL-2.0+ WITH Linux-syscall-note                       4
       LGPL-2.1 WITH Linux-syscall-note                        3
       ((GPL-2.0 WITH Linux-syscall-note) OR MIT)              3
       ((GPL-2.0 WITH Linux-syscall-note) AND MIT)             1

     and that resulted in the third patch in this series.

   - when the two scanners agreed on the detected license(s), that
     became the concluded license(s).

   - when there was disagreement between the two scanners (one detected
     a license but the other didn't, or they both detected different
     licenses) a manual inspection of the file occurred.

   - In most cases a manual inspection of the information in the file
     resulted in a clear resolution of the license that should apply
     (and which scanner probably needed to revisit its heuristics).

   - When it was not immediately clear, the license identifier was
     confirmed with lawyers working with the Linux Foundation.

   - If there was any question as to the appropriate license identifier,
     the file was flagged for further research and to be revisited later
     in time.

  In total, over 70 hours of logged manual review was done on the
  spreadsheet to determine the SPDX license identifiers to apply to the
  source files by Kate, Philippe, Thomas and, in some cases,
  confirmation by lawyers working with the Linux Foundation.

  Kate also obtained a third independent scan of the 4.13 code base from
  FOSSology, and compared selected files where the other two scanners
  disagreed against that SPDX file, to see if there was new insights.
  The Windriver scanner is based on an older version of FOSSology in
  part, so they are related.

  Thomas did random spot checks in about 500 files from the spreadsheets
  for the uapi headers and agreed with SPDX license identifier in the
  files he inspected. For the non-uapi files Thomas did random spot
  checks in about 15000 files.

  In initial set of patches against 4.14-rc6, 3 files were found to have
  copy/paste license identifier errors, and have been fixed to reflect
  the correct identifier.

  Additionally Philippe spent 10 hours this week doing a detailed manual
  inspection and review of the 12,461 patched files from the initial
  patch version early this week with:

   - a full scancode scan run, collecting the matched texts, detected
     license ids and scores

   - reviewing anything where there was a license detected (about 500+
     files) to ensure that the applied SPDX license was correct

   - reviewing anything where there was no detection but the patch
     license was not GPL-2.0 WITH Linux-syscall-note to ensure that the
     applied SPDX license was correct

  This produced a worksheet with 20 files needing minor correction. This
  worksheet was then exported into 3 different .csv files for the
  different types of files to be modified.

  These .csv files were then reviewed by Greg. Thomas wrote a script to
  parse the csv files and add the proper SPDX tag to the file, in the
  format that the file expected. This script was further refined by Greg
  based on the output to detect more types of files automatically and to
  distinguish between header and source .c files (which need different
  comment types.) Finally Greg ran the script using the .csv files to
  generate the patches.

  Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
  Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com>
  Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
  Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>"

* tag 'spdx_identifiers-4.14-rc8' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core:
  License cleanup: add SPDX license identifier to uapi header files with a license
  License cleanup: add SPDX license identifier to uapi header files with no license
  License cleanup: add SPDX GPL-2.0 license identifier to files with no license
2017-11-02 10:04:46 -07:00
Greg Kroah-Hartman b24413180f License cleanup: add SPDX GPL-2.0 license identifier to files with no license
Many source files in the tree are missing licensing information, which
makes it harder for compliance tools to determine the correct license.

By default all files without license information are under the default
license of the kernel, which is GPL version 2.

Update the files which contain no license information with the 'GPL-2.0'
SPDX license identifier.  The SPDX identifier is a legally binding
shorthand, which can be used instead of the full boiler plate text.

This patch is based on work done by Thomas Gleixner and Kate Stewart and
Philippe Ombredanne.

How this work was done:

Patches were generated and checked against linux-4.14-rc6 for a subset of
the use cases:
 - file had no licensing information it it.
 - file was a */uapi/* one with no licensing information in it,
 - file was a */uapi/* one with existing licensing information,

Further patches will be generated in subsequent months to fix up cases
where non-standard license headers were used, and references to license
had to be inferred by heuristics based on keywords.

The analysis to determine which SPDX License Identifier to be applied to
a file was done in a spreadsheet of side by side results from of the
output of two independent scanners (ScanCode & Windriver) producing SPDX
tag:value files created by Philippe Ombredanne.  Philippe prepared the
base worksheet, and did an initial spot review of a few 1000 files.

The 4.13 kernel was the starting point of the analysis with 60,537 files
assessed.  Kate Stewart did a file by file comparison of the scanner
results in the spreadsheet to determine which SPDX license identifier(s)
to be applied to the file. She confirmed any determination that was not
immediately clear with lawyers working with the Linux Foundation.

Criteria used to select files for SPDX license identifier tagging was:
 - Files considered eligible had to be source code files.
 - Make and config files were included as candidates if they contained >5
   lines of source
 - File already had some variant of a license header in it (even if <5
   lines).

All documentation files were explicitly excluded.

The following heuristics were used to determine which SPDX license
identifiers to apply.

 - when both scanners couldn't find any license traces, file was
   considered to have no license information in it, and the top level
   COPYING file license applied.

   For non */uapi/* files that summary was:

   SPDX license identifier                            # files
   ---------------------------------------------------|-------
   GPL-2.0                                              11139

   and resulted in the first patch in this series.

   If that file was a */uapi/* path one, it was "GPL-2.0 WITH
   Linux-syscall-note" otherwise it was "GPL-2.0".  Results of that was:

   SPDX license identifier                            # files
   ---------------------------------------------------|-------
   GPL-2.0 WITH Linux-syscall-note                        930

   and resulted in the second patch in this series.

 - if a file had some form of licensing information in it, and was one
   of the */uapi/* ones, it was denoted with the Linux-syscall-note if
   any GPL family license was found in the file or had no licensing in
   it (per prior point).  Results summary:

   SPDX license identifier                            # files
   ---------------------------------------------------|------
   GPL-2.0 WITH Linux-syscall-note                       270
   GPL-2.0+ WITH Linux-syscall-note                      169
   ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause)    21
   ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause)    17
   LGPL-2.1+ WITH Linux-syscall-note                      15
   GPL-1.0+ WITH Linux-syscall-note                       14
   ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause)    5
   LGPL-2.0+ WITH Linux-syscall-note                       4
   LGPL-2.1 WITH Linux-syscall-note                        3
   ((GPL-2.0 WITH Linux-syscall-note) OR MIT)              3
   ((GPL-2.0 WITH Linux-syscall-note) AND MIT)             1

   and that resulted in the third patch in this series.

 - when the two scanners agreed on the detected license(s), that became
   the concluded license(s).

 - when there was disagreement between the two scanners (one detected a
   license but the other didn't, or they both detected different
   licenses) a manual inspection of the file occurred.

 - In most cases a manual inspection of the information in the file
   resulted in a clear resolution of the license that should apply (and
   which scanner probably needed to revisit its heuristics).

 - When it was not immediately clear, the license identifier was
   confirmed with lawyers working with the Linux Foundation.

 - If there was any question as to the appropriate license identifier,
   the file was flagged for further research and to be revisited later
   in time.

In total, over 70 hours of logged manual review was done on the
spreadsheet to determine the SPDX license identifiers to apply to the
source files by Kate, Philippe, Thomas and, in some cases, confirmation
by lawyers working with the Linux Foundation.

Kate also obtained a third independent scan of the 4.13 code base from
FOSSology, and compared selected files where the other two scanners
disagreed against that SPDX file, to see if there was new insights.  The
Windriver scanner is based on an older version of FOSSology in part, so
they are related.

Thomas did random spot checks in about 500 files from the spreadsheets
for the uapi headers and agreed with SPDX license identifier in the
files he inspected. For the non-uapi files Thomas did random spot checks
in about 15000 files.

In initial set of patches against 4.14-rc6, 3 files were found to have
copy/paste license identifier errors, and have been fixed to reflect the
correct identifier.

Additionally Philippe spent 10 hours this week doing a detailed manual
inspection and review of the 12,461 patched files from the initial patch
version early this week with:
 - a full scancode scan run, collecting the matched texts, detected
   license ids and scores
 - reviewing anything where there was a license detected (about 500+
   files) to ensure that the applied SPDX license was correct
 - reviewing anything where there was no detection but the patch license
   was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied
   SPDX license was correct

This produced a worksheet with 20 files needing minor correction.  This
worksheet was then exported into 3 different .csv files for the
different types of files to be modified.

These .csv files were then reviewed by Greg.  Thomas wrote a script to
parse the csv files and add the proper SPDX tag to the file, in the
format that the file expected.  This script was further refined by Greg
based on the output to detect more types of files automatically and to
distinguish between header and source .c files (which need different
comment types.)  Finally Greg ran the script using the .csv files to
generate the patches.

Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-02 11:10:55 +01:00
Daniel Borkmann 5beca081be bpf: also improve pattern matches for meta access
Follow-up to 0fd4759c55 ("bpf: fix pattern matches for direct
packet access") to cover also the remaining data_meta/data matches
in the verifier. The matches are also refactored a bit to simplify
handling of all the cases.

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-02 17:01:38 +09:00
Daniel Borkmann b06723da82 bpf: minor cleanups after merge
Two minor cleanups after Dave's recent merge in f8ddadc4db
("Merge git://git.kernel.org...") of net into net-next in
order to get the code in line with what was done originally
in the net tree: i) use max() instead of max_t() since both
ranges are u16, ii) don't split the direct access test cases
in the middle with bpf_exit test cases from 390ee7e29f
("bpf: enforce return code for cgroup-bpf programs").

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-02 17:01:38 +09:00
Jesper Dangaard Brouer 03c4cc385f bpf: cpumap micro-optimization in cpu_map_enqueue
Discovered that the compiler laid-out asm code in suboptimal way
when studying perf report during benchmarking of cpumap. Help
the compiler by the marking unlikely code paths.

Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-02 16:13:14 +09:00
David S. Miller ed29668d1a Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Smooth Cong Wang's bug fix into 'net-next'.  Basically put
the bulk of the tcf_block_put() logic from 'net' into
tcf_block_put_ext(), but after the offload unbind.

Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-02 15:23:39 +09:00
Alexei Starovoitov 1969db47f8 bpf: fix verifier memory leaks
fix verifier memory leaks

Fixes: 638f5b90d4 ("bpf: reduce verifier memory consumption")
Signed-off-by: Alexei Starovoitov <ast@fb.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-01 22:07:31 +09:00
John Fastabend 04686ef299 bpf: remove SK_REDIRECT from UAPI
Now that SK_REDIRECT is no longer a valid return code. Remove it
from the UAPI completely. Then do a namespace remapping internal
to sockmap so SK_REDIRECT is no longer externally visible.

Patchs primary change is to do a namechange from SK_REDIRECT to
__SK_REDIRECT

Reported-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-01 11:43:50 +09:00
Alexei Starovoitov 638f5b90d4 bpf: reduce verifier memory consumption
the verifier got progressively smarter over time and size of its internal
state grew as well. Time to reduce the memory consumption.

Before:
sizeof(struct bpf_verifier_state) = 6520
After:
sizeof(struct bpf_verifier_state) = 896

It's done by observing that majority of BPF programs use little to
no stack whereas verifier kept all of 512 stack slots ready always.
Instead dynamically reallocate struct verifier state when stack
access is detected.
Runtime difference before vs after is within a noise.
The number of processed instructions stays the same.

Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-01 11:41:18 +09:00
David S. Miller e1ea2f9856 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Several conflicts here.

NFP driver bug fix adding nfp_netdev_is_nfp_repr() check to
nfp_fl_output() needed some adjustments because the code block is in
an else block now.

Parallel additions to net/pkt_cls.h and net/sch_generic.h

A bug fix in __tcp_retransmit_skb() conflicted with some of
the rbtree changes in net-next.

The tc action RCU callback fixes in 'net' had some overlap with some
of the recent tcf_block reworking.

Signed-off-by: David S. Miller <davem@davemloft.net>
2017-10-30 21:09:24 +09:00