Commit Graph

19 Commits

Author SHA1 Message Date
Daniel Borkmann 631b1e3b83 bpf, sparc: remove unused variable
Since fe83963b7c ("bpf, sparc64: remove ld_abs/ld_ind") it's not
used anymore therefore remove it.

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-05-14 19:11:45 -07:00
Daniel Borkmann fe83963b7c bpf, sparc64: remove ld_abs/ld_ind
Since LD_ABS/LD_IND instructions are now removed from the core and
reimplemented through a combination of inlined BPF instructions and
a slow-path helper, we can get rid of the complexity from sparc64 JIT.

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-05-03 16:49:20 -07:00
Daniel Borkmann 740d52c646 bpf, sparc64: remove obsolete exception handling from div/mod
Since we've changed div/mod exception handling for src_reg in
eBPF verifier itself, remove the leftovers from sparc64 JIT.

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Cc: David S. Miller <davem@davemloft.net>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-01-26 16:42:06 -08:00
Daniel Borkmann fa9dd599b4 bpf: get rid of pure_initcall dependency to enable jits
Having a pure_initcall() callback just to permanently enable BPF
JITs under CONFIG_BPF_JIT_ALWAYS_ON is unnecessary and could leave
a small race window in future where JIT is still disabled on boot.
Since we know about the setting at compilation time anyway, just
initialize it properly there. Also consolidate all the individual
bpf_jit_enable variables into a single one and move them under one
location. Moreover, don't allow for setting unspecified garbage
values on them.

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-01-19 18:37:00 -08:00
David S. Miller fcffe2edbd Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next
Daniel Borkmann says:

====================
pull-request: bpf-next 2017-12-28

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

The main changes are:

1) Fix incorrect state pruning related to recognition of zero initialized
   stack slots, where stacksafe exploration would mistakenly return a
   positive pruning verdict too early ignoring other slots, from Gianluca.

2) Various BPF to BPF calls related follow-up fixes. Fix an off-by-one
   in maximum call depth check, and rework maximum stack depth tracking
   logic to fix a bypass of the total stack size check reported by Jann.
   Also fix a bug in arm64 JIT where prog->jited_len was uninitialized.
   Addition of various test cases to BPF selftests, from Alexei.

3) Addition of a BPF selftest to test_verifier that is related to BPF to
   BPF calls which demonstrates a late caller stack size increase and
   thus out of bounds access. Fixed above in 2). Test case from Jann.

4) Addition of correlating BPF helper calls, BPF to BPF calls as well
   as BPF maps to bpftool xlated dump in order to allow for better
   BPF program introspection and debugging, from Daniel.

5) Fixing several bugs in BPF to BPF calls kallsyms handling in order
   to get it actually to work for subprogs, from Daniel.

6) Extending sparc64 JIT support for BPF to BPF calls and fix a couple
   of build errors for libbpf on sparc64, from David.

7) Allow narrower context access for BPF dev cgroup typed programs in
   order to adapt to LLVM code generation. Also adjust memlock rlimit
   in the test_dev_cgroup BPF selftest, from Yonghong.

8) Add netdevsim Kconfig entry to BPF selftests since test_offload.py
   relies on netdevsim device being available, from Jakub.

9) Reduce scope of xdp_do_generic_redirect_map() to being static,
   from Xiongwei.

10) Minor cleanups and spelling fixes in BPF verifier, from Colin.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2017-12-27 20:40:32 -05:00
David Miller 5f5a641116 bpf: sparc64: Add JIT support for multi-function programs.
Modelled strongly upon the arm64 implementation.

Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2017-12-23 01:00:52 +01:00
David S. Miller fba961ab29 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Lots of overlapping changes.  Also on the net-next side
the XDP state management is handled more in the generic
layers so undo the 'net' nfp fix which isn't applicable
in net-next.

Include a necessary change by Jakub Kicinski, with log message:

====================
cls_bpf no longer takes care of offload tracking.  Make sure
netdevsim performs necessary checks.  This fixes a warning
caused by TC trying to remove a filter it has not added.

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>
2017-12-22 11:16:31 -05:00
Alexei Starovoitov 60b58afc96 bpf: fix net.core.bpf_jit_enable race
global bpf_jit_enable variable is tested multiple times in JITs,
blinding and verifier core. The malicious root can try to toggle
it while loading the programs. This race condition was accounted
for and there should be no issues, but it's safer to avoid
this race condition.

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 20:34:36 +01:00
Daniel Borkmann 07aee94394 bpf, sparc: fix usage of wrong reg for load_skb_regs after call
When LD_ABS/IND is used in the program, and we have a BPF helper
call that changes packet data (bpf_helper_changes_pkt_data() returns
true), then in case of sparc JIT, we try to reload cached skb data
from bpf2sparc[BPF_REG_6]. However, there is no such guarantee or
assumption that skb sits in R6 at this point, all helpers changing
skb data only have a guarantee that skb sits in R1. Therefore,
store BPF R1 in L7 temporarily and after procedure call use L7 to
reload cached skb data. skb sitting in R6 is only true at the time
when LD_ABS/IND is executed.

Fixes: 7a12b5031c ("sparc64: Add eBPF JIT.")
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: David S. Miller <davem@davemloft.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2017-12-15 09:19:35 -08:00
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 18423550e3 bpf, sparc64: implement jiting of BPF_J{LT, LE, SLT, SLE}
This work implements jiting of BPF_J{LT,LE,SLT,SLE} instructions
with BPF_X/BPF_K variants for the sparc64 eBPF JIT.

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-08-09 16:53:57 -07:00
Martin KaFai Lau 783d28dd11 bpf: Add jited_len to struct bpf_prog
Add jited_len to struct bpf_prog.  It will be
useful for the struct bpf_prog_info which will
be added in the later patch.

Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Acked-by: Alexei Starovoitov <ast@fb.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-06-06 15:41:24 -04:00
David S. Miller a5e2ee5da4 bpf: Take advantage of stack_depth tracking in sparc64 JIT
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-05-31 19:35:00 -07:00
Alexei Starovoitov 71189fa9b0 bpf: free up BPF_JMP | BPF_CALL | BPF_X opcode
free up BPF_JMP | BPF_CALL | BPF_X opcode to be used by actual
indirect call by register and use kernel internal opcode to
mark call instruction into bpf_tail_call() helper.

Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-05-31 19:29:47 -04:00
David S. Miller e3bf4c61da sparc64: Fix BPF JIT wrt. branches and ldimm64 instructions.
Like other JITs, sparc64 maintains an array of instruction offsets but
stores the entries off by one.  This is done because jumps to the
exit block are indexed to one past the last BPF instruction.

So if we size the array by the program length, we need to record
the previous instruction in order to stay within the array bounds.

This is explained in ARM JIT commit 8eee539dde ("arm64: bpf: fix
out-of-bounds read in bpf2a64_offset()").

But this scheme requires a little bit of careful handling when
the instruction before the branch destination is a 64-bit load
immediate.  It takes up 2 BPF instruction slots.

Therefore, we have to fill in the array entry for the second
half of the 64-bit load immediate instruction rather than for
the one for the beginning of that instruction.

Fixes: 7a12b5031c ("sparc64: Add eBPF JIT.")
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-05-01 20:48:36 -07:00
David S. Miller 14933dc8d9 sparc64: Improve 64-bit constant loading in eBPF JIT.
Doing a full 64-bit decomposition is really stupid especially for
simple values like 0 and -1.

But if we are going to optimize this, go all the way and try for all 2
and 3 instruction sequences not requiring a temporary register as
well.

First we do the easy cases where it's a zero or sign extended 32-bit
number (sethi+or, sethi+xor, respectively).

Then we try to find a range of set bits we can load simply then shift
up into place, in various ways.

Then we try negating the constant and see if we can do a simple
sequence using that with a xor at the end.  (f.e. the range of set
bits can't be loaded simply, but for the negated value it can)

The final optimized strategy involves 4 instructions sequences not
needing a temporary register.

Otherwise we sadly fully decompose using a temp..

Example, from ALU64_XOR_K: 0x0000ffffffff0000 ^ 0x0 = 0x0000ffffffff0000:

0000000000000000 <foo>:
   0:   9d e3 bf 50     save  %sp, -176, %sp
   4:   01 00 00 00     nop
   8:   90 10 00 18     mov  %i0, %o0
   c:   13 3f ff ff     sethi  %hi(0xfffffc00), %o1
  10:   92 12 63 ff     or  %o1, 0x3ff, %o1     ! ffffffff <foo+0xffffffff>
  14:   93 2a 70 10     sllx  %o1, 0x10, %o1
  18:   15 3f ff ff     sethi  %hi(0xfffffc00), %o2
  1c:   94 12 a3 ff     or  %o2, 0x3ff, %o2     ! ffffffff <foo+0xffffffff>
  20:   95 2a b0 10     sllx  %o2, 0x10, %o2
  24:   92 1a 60 00     xor  %o1, 0, %o1
  28:   12 e2 40 8a     cxbe  %o1, %o2, 38 <foo+0x38>
  2c:   9a 10 20 02     mov  2, %o5
  30:   10 60 00 03     b,pn   %xcc, 3c <foo+0x3c>
  34:   01 00 00 00     nop
  38:   9a 10 20 01     mov  1, %o5     ! 1 <foo+0x1>
  3c:   81 c7 e0 08     ret
  40:   91 eb 40 00     restore  %o5, %g0, %o0

Signed-off-by: David S. Miller <davem@davemloft.net>
2017-04-24 20:32:15 -07:00
David S. Miller e3a724edee sparc64: Support cbcond instructions in eBPF JIT.
cbcond combines a compare with a branch into a single instruction.

The limitations are:

1) Only newer chips support it

2) For immediate compares we are limited to 5-bit signed immediate
   values

3) The branch displacement is limited to 10-bit signed

4) We cannot use it for JSET

Also, cbcond (unlike all other sparc control transfers) lacks a delay
slot.

Currently we don't have a useful instruction we can push into the
delay slot of normal branches.  So using cbcond pretty much always
increases code density, and is therefore a win.

Signed-off-by: David S. Miller <davem@davemloft.net>
2017-04-24 15:56:21 -07:00
David S. Miller 7a12b5031c sparc64: Add eBPF JIT.
This is an eBPF JIT for sparc64.  All major features are supported.

All tests under tools/testing/selftests/bpf/ pass.

Signed-off-by: David S. Miller <davem@davemloft.net>
2017-04-22 12:10:52 -07:00
David S. Miller 6b3d4eec7f sparc: Split BPF JIT into 32-bit and 64-bit.
This is in preparation for adding the 64-bit eBPF JIT.

Signed-off-by: David S. Miller <davem@davemloft.net>
2017-04-22 12:10:52 -07:00