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Daniel Borkmann ddc665a4bb bpf, arm64: fix jit branch offset related to ldimm64
When the instruction right before the branch destination is
a 64 bit load immediate, we currently calculate the wrong
jump offset in the ctx->offset[] array as we only account
one instruction slot for the 64 bit load immediate although
it uses two BPF instructions. Fix it up by setting the offset
into the right slot after we incremented the index.

Before (ldimm64 test 1):

  [...]
  00000020:  52800007  mov w7, #0x0 // #0
  00000024:  d2800060  mov x0, #0x3 // #3
  00000028:  d2800041  mov x1, #0x2 // #2
  0000002c:  eb01001f  cmp x0, x1
  00000030:  54ffff82  b.cs 0x00000020
  00000034:  d29fffe7  mov x7, #0xffff // #65535
  00000038:  f2bfffe7  movk x7, #0xffff, lsl #16
  0000003c:  f2dfffe7  movk x7, #0xffff, lsl #32
  00000040:  f2ffffe7  movk x7, #0xffff, lsl #48
  00000044:  d29dddc7  mov x7, #0xeeee // #61166
  00000048:  f2bdddc7  movk x7, #0xeeee, lsl #16
  0000004c:  f2ddddc7  movk x7, #0xeeee, lsl #32
  00000050:  f2fdddc7  movk x7, #0xeeee, lsl #48
  [...]

After (ldimm64 test 1):

  [...]
  00000020:  52800007  mov w7, #0x0 // #0
  00000024:  d2800060  mov x0, #0x3 // #3
  00000028:  d2800041  mov x1, #0x2 // #2
  0000002c:  eb01001f  cmp x0, x1
  00000030:  540000a2  b.cs 0x00000044
  00000034:  d29fffe7  mov x7, #0xffff // #65535
  00000038:  f2bfffe7  movk x7, #0xffff, lsl #16
  0000003c:  f2dfffe7  movk x7, #0xffff, lsl #32
  00000040:  f2ffffe7  movk x7, #0xffff, lsl #48
  00000044:  d29dddc7  mov x7, #0xeeee // #61166
  00000048:  f2bdddc7  movk x7, #0xeeee, lsl #16
  0000004c:  f2ddddc7  movk x7, #0xeeee, lsl #32
  00000050:  f2fdddc7  movk x7, #0xeeee, lsl #48
  [...]

Also, add a couple of test cases to make sure JITs pass
this test. Tested on Cavium ThunderX ARMv8. The added
test cases all pass after the fix.

Fixes: 8eee539dde ("arm64: bpf: fix out-of-bounds read in bpf2a64_offset()")
Reported-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Cc: Xi Wang <xi.wang@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-05-02 15:04:50 -04:00
Documentation switchdev: documentation: fix whitespace issues 2017-05-01 13:52:43 -04:00
arch bpf, arm64: fix jit branch offset related to ldimm64 2017-05-02 15:04:50 -04:00
block blk-mq: fix potential oops with polling and blk-mq scheduler 2017-04-20 14:53:28 -06:00
certs certs: Add a secondary system keyring that can be added to dynamically 2016-04-11 22:48:09 +01:00
crypto Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2017-04-20 10:35:33 -04:00
drivers net: dsa: mv88e6xxx: add VTU support for 88E6390 2017-05-01 15:03:13 -04:00
firmware WHENCE: use https://linuxtv.org for LinuxTV URLs 2015-12-04 10:35:11 -02:00
fs Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2017-04-26 22:39:08 -04:00
include rhashtable: compact struct rhashtable_params 2017-05-01 16:22:40 -04:00
init mm: move mm_percpu_wq initialization earlier 2017-03-31 17:13:30 -07:00
ipc Merge branch 'WIP.sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2017-03-03 10:16:38 -08:00
kernel bpf: enhance verifier to understand stack pointer arithmetic 2017-05-01 11:40:23 -04:00
lib bpf, arm64: fix jit branch offset related to ldimm64 2017-05-02 15:04:50 -04:00
mm mm: prevent NR_ISOLATE_* stats from going negative 2017-04-20 15:30:18 -07:00
net bpf: Align packet data properly in program testing framework. 2017-05-02 11:46:28 -04:00
samples bpf, samples: fix build warning in cookie_uid_helper_example 2017-05-02 09:29:35 -04:00
scripts Kbuild fixes for v4.11 2017-04-05 08:37:28 -07:00
security Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2017-04-21 20:23:53 -07:00
sound ASoC: Fixes for v4.11 2017-04-25 17:43:56 +02:00
tools selftests: bpf: Use bpf_endian.h in test_xdp.c 2017-05-02 07:52:01 -07:00
usr kbuild: initramfs cleanup, set target from Kconfig 2017-01-05 09:40:16 -08:00
virt KVM/ARM Fixes for v4.11-rc6 2017-04-05 16:27:47 +02:00
.cocciconfig scripts: add Linux .cocciconfig for coccinelle 2016-07-22 12:13:39 +02:00
.get_maintainer.ignore Add hch to .get_maintainer.ignore 2015-08-21 14:30:10 -07:00
.gitattributes .gitattributes: set git diff driver for C source code files 2016-10-07 18:46:30 -07:00
.gitignore Merge branch 'misc' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild 2016-08-02 16:48:52 -04:00
.mailmap mailmap: add Martin Kepplinger's email 2017-04-13 18:24:21 -07:00
COPYING
CREDITS MAINTAINERS: Remove old e-mail address 2017-02-13 12:24:56 -05:00
Kbuild scripts/gdb: provide linux constants 2016-05-23 17:04:14 -07:00
Kconfig
MAINTAINERS VSOCK: Add vsockmon device 2017-04-24 12:35:56 -04:00
Makefile Linux 4.11-rc8 2017-04-23 16:53:00 -07:00
README README: add a new README file, pointing to the Documentation/ 2016-10-24 08:12:35 -02:00

README

Linux kernel
============

This file was moved to Documentation/admin-guide/README.rst

Please notice that there are several guides for kernel developers and users.
These guides can be rendered in a number of formats, like HTML and PDF.

In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``.

There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
See Documentation/00-INDEX for a list of what is contained in each file.

Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.