Commit Graph

44 Commits

Author SHA1 Message Date
Christoph Hellwig
4f010246b4 net/bpfilter: Initialize pos in __bpfilter_process_sockopt
__bpfilter_process_sockopt never initialized the pos variable passed
to the pipe write. This has been mostly harmless in the past as pipes
ignore the offset, but the switch to kernel_write now verified the
position, which can lead to a failure depending on the exact stack
initialization pattern. Initialize the variable to zero to make
rw_verify_area happy.

Fixes: 6955a76fbc ("bpfilter: switch to kernel_write")
Reported-by: Christian Brauner <christian.brauner@ubuntu.com>
Reported-by: Rodrigo Madera <rodrigo.madera@gmail.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Tested-by: Rodrigo Madera <rodrigo.madera@gmail.com>
Tested-by: Christian Brauner <christian.brauner@ubuntu.com>
Reviewed-by: Christian Brauner <christian.brauner@ubuntu.com>
Link: https://lore.kernel.org/bpf/20200730160900.187157-1-hch@lst.de
2020-07-31 01:07:32 +02:00
Valdis Kl ē tnieks
9f64fbdb77 bpfilter: document build requirements for bpfilter_umh
It's not intuitively obvious that bpfilter_umh is a statically linked binary.
Mention the toolchain requirement in the Kconfig help, so people
have an easier time figuring out what's needed.

Signed-off-by: Valdis Kletnieks <valdis.kletnieks@vt.edu>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-05-26 00:03:16 +09:00
Masahiro Yamada
8a2cc0505c bpfilter: use 'userprogs' syntax to build bpfilter_umh
The user mode helper should be compiled for the same architecture as
the kernel.

This Makefile reused the 'hostprogs' syntax by overriding HOSTCC with CC.
Use the new syntax 'userprogs' to fix the Makefile mess.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Acked-by: Sam Ravnborg <sam@ravnborg.org>
2020-05-17 18:52:01 +09:00
Masahiro Yamada
b1183b6dca bpfilter: check if $(CC) can link static libc in Kconfig
On Fedora, linking static glibc requires the glibc-static RPM package,
which is not part of the glibc-devel package.

CONFIG_CC_CAN_LINK does not check the capability of static linking,
so you can enable CONFIG_BPFILTER_UMH, then fail to build:

    HOSTLD  net/bpfilter/bpfilter_umh
  /usr/bin/ld: cannot find -lc
  collect2: error: ld returned 1 exit status

Add CONFIG_CC_CAN_LINK_STATIC, and make CONFIG_BPFILTER_UMH depend
on it.

Reported-by: Valdis Kletnieks <valdis.kletnieks@vt.edu>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Acked-by: Alexei Starovoitov <ast@kernel.org>
2020-05-17 18:52:01 +09:00
Masahiro Yamada
9371f86ecb bpfilter: match bit size of bpfilter_umh to that of the kernel
bpfilter_umh is built for the default machine bit of the compiler,
which may not match to the bit size of the kernel.

This happens in the scenario below:

You can use biarch GCC that defaults to 64-bit for building the 32-bit
kernel. In this case, Kbuild passes -m32 to teach the compiler to
produce 32-bit kernel space objects. However, it is missing when
building bpfilter_umh. It is built as a 64-bit ELF, and then embedded
into the 32-bit kernel.

The 32-bit kernel and 64-bit umh is a bad combination.

In theory, we can have 32-bit umh running on 64-bit kernel, but we do
not have a good reason to support such a usecase.

The best is to match the bit size between them.

Pass -m32 or -m64 to the umh build command if it is found in
$(KBUILD_CFLAGS). Evaluate CC_CAN_LINK against the kernel bit-size.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-05-17 18:52:01 +09:00
Linus Torvalds
ff2ae607c6 SPDX patches for 5.7-rc1.
Here are 3 SPDX patches for 5.7-rc1.
 
 One fixes up the SPDX tag for a single driver, while the other two go
 through the tree and add SPDX tags for all of the .gitignore files as
 needed.
 
 Nothing too complex, but you will get a merge conflict with your current
 tree, that should be trivial to handle (one file modified by two things,
 one file deleted.)
 
 All 3 of these have been in linux-next for a while, with no reported
 issues other than the merge conflict.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'spdx-5.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/spdx

Pull SPDX updates from Greg KH:
 "Here are three SPDX patches for 5.7-rc1.

  One fixes up the SPDX tag for a single driver, while the other two go
  through the tree and add SPDX tags for all of the .gitignore files as
  needed.

  Nothing too complex, but you will get a merge conflict with your
  current tree, that should be trivial to handle (one file modified by
  two things, one file deleted.)

  All three of these have been in linux-next for a while, with no
  reported issues other than the merge conflict"

* tag 'spdx-5.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/spdx:
  ASoC: MT6660: make spdxcheck.py happy
  .gitignore: add SPDX License Identifier
  .gitignore: remove too obvious comments
2020-04-03 13:12:26 -07:00
Bruno Meneguele
41c55ea6c2 net/bpfilter: remove superfluous testing message
A testing message was brought by 13d0f7b814 ("net/bpfilter: fix dprintf
usage for /dev/kmsg") but should've been deleted before patch submission.
Although it doesn't cause any harm to the code or functionality itself, it's
totally unpleasant to have it displayed on every loop iteration with no real
use case. Thus remove it unconditionally.

Fixes: 13d0f7b814 ("net/bpfilter: fix dprintf usage for /dev/kmsg")
Signed-off-by: Bruno Meneguele <bmeneg@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-03-31 10:07:51 -07:00
Masahiro Yamada
d198b34f38 .gitignore: add SPDX License Identifier
Add SPDX License Identifier to all .gitignore files.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-25 11:50:48 +01:00
Bruno Meneguele
13d0f7b814 net/bpfilter: fix dprintf usage for /dev/kmsg
The bpfilter UMH code was recently changed to log its informative messages to
/dev/kmsg, however this interface doesn't support SEEK_CUR yet, used by
dprintf(). As result dprintf() returns -EINVAL and doesn't log anything.

However there already had some discussions about supporting SEEK_CUR into
/dev/kmsg interface in the past it wasn't concluded. Since the only user of
that from userspace perspective inside the kernel is the bpfilter UMH
(userspace) module it's better to correct it here instead waiting a conclusion
on the interface.

Fixes: 36c4357c63 ("net: bpfilter: print umh messages to /dev/kmsg")
Signed-off-by: Bruno Meneguele <bmeneg@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-03-14 20:58:10 -07:00
Masahiro Yamada
5f2fb52fac kbuild: rename hostprogs-y/always to hostprogs/always-y
In old days, the "host-progs" syntax was used for specifying host
programs. It was renamed to the current "hostprogs-y" in 2004.

It is typically useful in scripts/Makefile because it allows Kbuild to
selectively compile host programs based on the kernel configuration.

This commit renames like follows:

  always       ->  always-y
  hostprogs-y  ->  hostprogs

So, scripts/Makefile will look like this:

  always-$(CONFIG_BUILD_BIN2C) += ...
  always-$(CONFIG_KALLSYMS)    += ...
      ...
  hostprogs := $(always-y) $(always-m)

I think this makes more sense because a host program is always a host
program, irrespective of the kernel configuration. We want to specify
which ones to compile by CONFIG options, so always-y will be handier.

The "always", "hostprogs-y", "hostprogs-m" will be kept for backward
compatibility for a while.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-02-04 01:53:07 +09:00
Linus Torvalds
39ceda5ce1 Kbuild updates for v5.3
- remove headers_{install,check}_all targets
 
 - remove unreasonable 'depends on !UML' from CONFIG_SAMPLES
 
 - re-implement 'make headers_install' more cleanly
 
 - add new header-test-y syntax to compile-test headers
 
 - compile-test exported headers to ensure they are compilable in
   user-space
 
 - compile-test headers under include/ to ensure they are self-contained
 
 - remove -Waggregate-return, -Wno-uninitialized, -Wno-unused-value flags
 
 - add -Werror=unknown-warning-option for Clang
 
 - add 128-bit built-in types support to genksyms
 
 - fix missed rebuild of modules.builtin
 
 - propagate 'No space left on device' error in fixdep to Make
 
 - allow Clang to use its integrated assembler
 
 - improve some coccinelle scripts
 
 - add a new flag KBUILD_ABS_SRCTREE to request Kbuild to use absolute
   path for $(srctree).
 
 - do not ignore errors when compression utility is missing
 
 - misc cleanups
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Merge tag 'kbuild-v5.3' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild

Pull Kbuild updates from Masahiro Yamada:

 - remove headers_{install,check}_all targets

 - remove unreasonable 'depends on !UML' from CONFIG_SAMPLES

 - re-implement 'make headers_install' more cleanly

 - add new header-test-y syntax to compile-test headers

 - compile-test exported headers to ensure they are compilable in
   user-space

 - compile-test headers under include/ to ensure they are self-contained

 - remove -Waggregate-return, -Wno-uninitialized, -Wno-unused-value
   flags

 - add -Werror=unknown-warning-option for Clang

 - add 128-bit built-in types support to genksyms

 - fix missed rebuild of modules.builtin

 - propagate 'No space left on device' error in fixdep to Make

 - allow Clang to use its integrated assembler

 - improve some coccinelle scripts

 - add a new flag KBUILD_ABS_SRCTREE to request Kbuild to use absolute
   path for $(srctree).

 - do not ignore errors when compression utility is missing

 - misc cleanups

* tag 'kbuild-v5.3' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (49 commits)
  kbuild: use -- separater intead of $(filter-out ...) for cc-cross-prefix
  kbuild: Inform user to pass ARCH= for make mrproper
  kbuild: fix compression errors getting ignored
  kbuild: add a flag to force absolute path for srctree
  kbuild: replace KBUILD_SRCTREE with boolean building_out_of_srctree
  kbuild: remove src and obj from the top Makefile
  scripts/tags.sh: remove unused environment variables from comments
  scripts/tags.sh: drop SUBARCH support for ARM
  kbuild: compile-test kernel headers to ensure they are self-contained
  kheaders: include only headers into kheaders_data.tar.xz
  kheaders: remove meaningless -R option of 'ls'
  kbuild: support header-test-pattern-y
  kbuild: do not create wrappers for header-test-y
  kbuild: compile-test exported headers to ensure they are self-contained
  init/Kconfig: add CONFIG_CC_CAN_LINK
  kallsyms: exclude kasan local symbols on s390
  kbuild: add more hints about SUBDIRS replacement
  coccinelle: api/stream_open: treat all wait_.*() calls as blocking
  coccinelle: put_device: Add a cast to an expression for an assignment
  coccinelle: put_device: Adjust a message construction
  ...
2019-07-12 16:03:16 -07:00
Linus Torvalds
237f83dfbe Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next
Pull networking updates from David Miller:
 "Some highlights from this development cycle:

   1) Big refactoring of ipv6 route and neigh handling to support
      nexthop objects configurable as units from userspace. From David
      Ahern.

   2) Convert explored_states in BPF verifier into a hash table,
      significantly decreased state held for programs with bpf2bpf
      calls, from Alexei Starovoitov.

   3) Implement bpf_send_signal() helper, from Yonghong Song.

   4) Various classifier enhancements to mvpp2 driver, from Maxime
      Chevallier.

   5) Add aRFS support to hns3 driver, from Jian Shen.

   6) Fix use after free in inet frags by allocating fqdirs dynamically
      and reworking how rhashtable dismantle occurs, from Eric Dumazet.

   7) Add act_ctinfo packet classifier action, from Kevin
      Darbyshire-Bryant.

   8) Add TFO key backup infrastructure, from Jason Baron.

   9) Remove several old and unused ISDN drivers, from Arnd Bergmann.

  10) Add devlink notifications for flash update status to mlxsw driver,
      from Jiri Pirko.

  11) Lots of kTLS offload infrastructure fixes, from Jakub Kicinski.

  12) Add support for mv88e6250 DSA chips, from Rasmus Villemoes.

  13) Various enhancements to ipv6 flow label handling, from Eric
      Dumazet and Willem de Bruijn.

  14) Support TLS offload in nfp driver, from Jakub Kicinski, Dirk van
      der Merwe, and others.

  15) Various improvements to axienet driver including converting it to
      phylink, from Robert Hancock.

  16) Add PTP support to sja1105 DSA driver, from Vladimir Oltean.

  17) Add mqprio qdisc offload support to dpaa2-eth, from Ioana
      Radulescu.

  18) Add devlink health reporting to mlx5, from Moshe Shemesh.

  19) Convert stmmac over to phylink, from Jose Abreu.

  20) Add PTP PHC (Physical Hardware Clock) support to mlxsw, from
      Shalom Toledo.

  21) Add nftables SYNPROXY support, from Fernando Fernandez Mancera.

  22) Convert tcp_fastopen over to use SipHash, from Ard Biesheuvel.

  23) Track spill/fill of constants in BPF verifier, from Alexei
      Starovoitov.

  24) Support bounded loops in BPF, from Alexei Starovoitov.

  25) Various page_pool API fixes and improvements, from Jesper Dangaard
      Brouer.

  26) Just like ipv4, support ref-countless ipv6 route handling. From
      Wei Wang.

  27) Support VLAN offloading in aquantia driver, from Igor Russkikh.

  28) Add AF_XDP zero-copy support to mlx5, from Maxim Mikityanskiy.

  29) Add flower GRE encap/decap support to nfp driver, from Pieter
      Jansen van Vuuren.

  30) Protect against stack overflow when using act_mirred, from John
      Hurley.

  31) Allow devmap map lookups from eBPF, from Toke Høiland-Jørgensen.

  32) Use page_pool API in netsec driver, Ilias Apalodimas.

  33) Add Google gve network driver, from Catherine Sullivan.

  34) More indirect call avoidance, from Paolo Abeni.

  35) Add kTLS TX HW offload support to mlx5, from Tariq Toukan.

  36) Add XDP_REDIRECT support to bnxt_en, from Andy Gospodarek.

  37) Add MPLS manipulation actions to TC, from John Hurley.

  38) Add sending a packet to connection tracking from TC actions, and
      then allow flower classifier matching on conntrack state. From
      Paul Blakey.

  39) Netfilter hw offload support, from Pablo Neira Ayuso"

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (2080 commits)
  net/mlx5e: Return in default case statement in tx_post_resync_params
  mlx5: Return -EINVAL when WARN_ON_ONCE triggers in mlx5e_tls_resync().
  net: dsa: add support for BRIDGE_MROUTER attribute
  pkt_sched: Include const.h
  net: netsec: remove static declaration for netsec_set_tx_de()
  net: netsec: remove superfluous if statement
  netfilter: nf_tables: add hardware offload support
  net: flow_offload: rename tc_cls_flower_offload to flow_cls_offload
  net: flow_offload: add flow_block_cb_is_busy() and use it
  net: sched: remove tcf block API
  drivers: net: use flow block API
  net: sched: use flow block API
  net: flow_offload: add flow_block_cb_{priv, incref, decref}()
  net: flow_offload: add list handling functions
  net: flow_offload: add flow_block_cb_alloc() and flow_block_cb_free()
  net: flow_offload: rename TCF_BLOCK_BINDER_TYPE_* to FLOW_BLOCK_BINDER_TYPE_*
  net: flow_offload: rename TC_BLOCK_{UN}BIND to FLOW_BLOCK_{UN}BIND
  net: flow_offload: add flow_block_cb_setup_simple()
  net: hisilicon: Add an tx_desc to adapt HI13X1_GMAC
  net: hisilicon: Add an rx_desc to adapt HI13X1_GMAC
  ...
2019-07-11 10:55:49 -07:00
Linus Torvalds
5ad18b2e60 Merge branch 'siginfo-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace
Pull force_sig() argument change from Eric Biederman:
 "A source of error over the years has been that force_sig has taken a
  task parameter when it is only safe to use force_sig with the current
  task.

  The force_sig function is built for delivering synchronous signals
  such as SIGSEGV where the userspace application caused a synchronous
  fault (such as a page fault) and the kernel responded with a signal.

  Because the name force_sig does not make this clear, and because the
  force_sig takes a task parameter the function force_sig has been
  abused for sending other kinds of signals over the years. Slowly those
  have been fixed when the oopses have been tracked down.

  This set of changes fixes the remaining abusers of force_sig and
  carefully rips out the task parameter from force_sig and friends
  making this kind of error almost impossible in the future"

* 'siginfo-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace: (27 commits)
  signal/x86: Move tsk inside of CONFIG_MEMORY_FAILURE in do_sigbus
  signal: Remove the signal number and task parameters from force_sig_info
  signal: Factor force_sig_info_to_task out of force_sig_info
  signal: Generate the siginfo in force_sig
  signal: Move the computation of force into send_signal and correct it.
  signal: Properly set TRACE_SIGNAL_LOSE_INFO in __send_signal
  signal: Remove the task parameter from force_sig_fault
  signal: Use force_sig_fault_to_task for the two calls that don't deliver to current
  signal: Explicitly call force_sig_fault on current
  signal/unicore32: Remove tsk parameter from __do_user_fault
  signal/arm: Remove tsk parameter from __do_user_fault
  signal/arm: Remove tsk parameter from ptrace_break
  signal/nds32: Remove tsk parameter from send_sigtrap
  signal/riscv: Remove tsk parameter from do_trap
  signal/sh: Remove tsk parameter from force_sig_info_fault
  signal/um: Remove task parameter from send_sigtrap
  signal/x86: Remove task parameter from send_sigtrap
  signal: Remove task parameter from force_sig_mceerr
  signal: Remove task parameter from force_sig
  signal: Remove task parameter from force_sigsegv
  ...
2019-07-08 21:48:15 -07:00
Gary Lin
36c4357c63 net: bpfilter: print umh messages to /dev/kmsg
bpfilter_umh currently printed all messages to /dev/console and this
might interfere the user activity(*).

This commit changes the output device to /dev/kmsg so that the messages
from bpfilter_umh won't show on the console directly.

(*) https://bugzilla.suse.com/show_bug.cgi?id=1140221

Signed-off-by: Gary Lin <glin@suse.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-07-07 22:16:11 -07:00
Masahiro Yamada
1a927fd347 init/Kconfig: add CONFIG_CC_CAN_LINK
Currently, scripts/cc-can-link.sh is run just for BPFILTER_UMH, but
defining CC_CAN_LINK will be useful in other places.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2019-07-08 02:25:59 +09:00
Eric W. Biederman
1dfd1711de signal/bpfilter: Fix bpfilter_kernl to use send_sig not force_sig
The locking in force_sig_info is not prepared to deal with
a task that exits or execs (as sighand may change).  As force_sig
is only built to handle synchronous exceptions.

Further the function force_sig_info changes the signal state if the
signal is ignored, or blocked or if SIGNAL_UNKILLABLE will prevent the
delivery of the signal.  The signal SIGKILL can not be ignored and can
not be blocked and SIGNAL_UNKILLABLE won't prevent it from being
delivered.

So using force_sig rather than send_sig for SIGKILL is pointless.

Because it won't impact the sending of the signal and and because
using force_sig is wrong, replace force_sig with send_sig.

Cc: Alexei Starovoitov <ast@kernel.org>
Cc: David S. Miller <davem@davemloft.net>
Fixes: d2ba09c17a ("net: add skeleton of bpfilter kernel module")
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2019-05-27 09:36:28 -05:00
Thomas Gleixner
ec8f24b7fa treewide: Add SPDX license identifier - Makefile/Kconfig
Add SPDX license identifiers to all Make/Kconfig files which:

 - Have no license information of any form

These files fall under the project license, GPL v2 only. The resulting SPDX
license identifier is:

  GPL-2.0-only

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-21 10:50:46 +02:00
Masahiro Yamada
9cc342f6c4 treewide: prefix header search paths with $(srctree)/
Currently, the Kbuild core manipulates header search paths in a crazy
way [1].

To fix this mess, I want all Makefiles to add explicit $(srctree)/ to
the search paths in the srctree. Some Makefiles are already written in
that way, but not all. The goal of this work is to make the notation
consistent, and finally get rid of the gross hacks.

Having whitespaces after -I does not matter since commit 48f6e3cf5b
("kbuild: do not drop -I without parameter").

[1]: https://patchwork.kernel.org/patch/9632347/

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2019-05-18 11:49:57 +09:00
Masahiro Yamada
dccd3ab55e bpfilter: re-add header search paths to tools include to fix build error
I thought header search paths to tools/include(/uapi) were unneeded,
but it looks like a build error occurs depending on the compiler.

Commit 303a339f30 ("bpfilter: remove extra header search paths for
bpfilter_umh") reintroduced the build error fixed by commit ae40832e53
("bpfilter: fix a build err").

Apology for the breakage, and thanks to Guenter for reporting this.

Fixes: 303a339f30 ("bpfilter: remove extra header search paths for bpfilter_umh")
Reported-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Tested-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-02-23 13:34:40 -08:00
Masahiro Yamada
303a339f30 bpfilter: remove extra header search paths for bpfilter_umh
Currently, the header search paths -Itools/include and
-Itools/include/uapi are not used. Let's drop the unused code.

We can remove -I. too by fixing up one C file.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-02-03 20:11:43 -08:00
Taehee Yoo
1a9352687c net: bpfilter: change section name of bpfilter UMH blob.
The section of bpfilter UMH blob is the ".bpfilter_umh". but this is not
an explicit section. so linking warning occurred at compile time for the
powerpc.
So, this patch makes use of the ".rodata" instead of the ".bpfilter_umh".

Config condition:

CONFIG_BPFILTER=y
CONFIG_BPFILTER_UMH=y

Result:

ld: warning: orphan section `.bpfilter_umh' from
`net/bpfilter/bpfilter_umh_blob.o' being placed in section `.bpfilter_umh'

Fixes: 61fbf5933d ("net: bpfilter: restart bpfilter_umh when error occurred")
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Taehee Yoo <ap420073@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-01-16 15:46:46 -08:00
Taehee Yoo
71a8508402 net: bpfilter: disallow to remove bpfilter module while being used
The bpfilter.ko module can be removed while functions of the bpfilter.ko
are executing. so panic can occurred. in order to protect that, locks can
be used. a bpfilter_lock protects routines in the
__bpfilter_process_sockopt() but it's not enough because __exit routine
can be executed concurrently.

Now, the bpfilter_umh can not run in parallel.
So, the module do not removed while it's being used and it do not
double-create UMH process.
The members of the umh_info and the bpfilter_umh_ops are protected by
the bpfilter_umh_ops.lock.

test commands:
   while :
   do
	iptables -I FORWARD -m string --string ap --algo kmp &
	modprobe -rv bpfilter &
   done

splat looks like:
[  298.623435] BUG: unable to handle kernel paging request at fffffbfff807440b
[  298.628512] #PF error: [normal kernel read fault]
[  298.633018] PGD 124327067 P4D 124327067 PUD 11c1a3067 PMD 119eb2067 PTE 0
[  298.638859] Oops: 0000 [#1] SMP DEBUG_PAGEALLOC KASAN PTI
[  298.638859] CPU: 0 PID: 2997 Comm: iptables Not tainted 4.20.0+ #154
[  298.638859] RIP: 0010:__mutex_lock+0x6b9/0x16a0
[  298.638859] Code: c0 00 00 e8 89 82 ff ff 80 bd 8f fc ff ff 00 0f 85 d9 05 00 00 48 8b 85 80 fc ff ff 48 bf 00 00 00 00 00 fc ff df 48 c1 e8 03 <80> 3c 38 00 0f 85 1d 0e 00 00 48 8b 85 c8 fc ff ff 49 39 47 58 c6
[  298.638859] RSP: 0018:ffff88810e7777a0 EFLAGS: 00010202
[  298.638859] RAX: 1ffffffff807440b RBX: ffff888111bd4d80 RCX: 0000000000000000
[  298.638859] RDX: 1ffff110235ff806 RSI: ffff888111bd5538 RDI: dffffc0000000000
[  298.638859] RBP: ffff88810e777b30 R08: 0000000080000002 R09: 0000000000000000
[  298.638859] R10: 0000000000000000 R11: 0000000000000000 R12: fffffbfff168a42c
[  298.638859] R13: ffff888111bd4d80 R14: ffff8881040e9a05 R15: ffffffffc03a2000
[  298.638859] FS:  00007f39e3758700(0000) GS:ffff88811ae00000(0000) knlGS:0000000000000000
[  298.638859] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  298.638859] CR2: fffffbfff807440b CR3: 000000011243e000 CR4: 00000000001006f0
[  298.638859] Call Trace:
[  298.638859]  ? mutex_lock_io_nested+0x1560/0x1560
[  298.638859]  ? kasan_kmalloc+0xa0/0xd0
[  298.638859]  ? kmem_cache_alloc+0x1c2/0x260
[  298.638859]  ? __alloc_file+0x92/0x3c0
[  298.638859]  ? alloc_empty_file+0x43/0x120
[  298.638859]  ? alloc_file_pseudo+0x220/0x330
[  298.638859]  ? sock_alloc_file+0x39/0x160
[  298.638859]  ? __sys_socket+0x113/0x1d0
[  298.638859]  ? __x64_sys_socket+0x6f/0xb0
[  298.638859]  ? do_syscall_64+0x138/0x560
[  298.638859]  ? entry_SYSCALL_64_after_hwframe+0x49/0xbe
[  298.638859]  ? __alloc_file+0x92/0x3c0
[  298.638859]  ? init_object+0x6b/0x80
[  298.638859]  ? cyc2ns_read_end+0x10/0x10
[  298.638859]  ? cyc2ns_read_end+0x10/0x10
[  298.638859]  ? hlock_class+0x140/0x140
[  298.638859]  ? sched_clock_local+0xd4/0x140
[  298.638859]  ? sched_clock_local+0xd4/0x140
[  298.638859]  ? check_flags.part.37+0x440/0x440
[  298.638859]  ? __lock_acquire+0x4f90/0x4f90
[  298.638859]  ? set_rq_offline.part.89+0x140/0x140
[ ... ]

Fixes: d2ba09c17a ("net: add skeleton of bpfilter kernel module")
Signed-off-by: Taehee Yoo <ap420073@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-01-11 18:05:41 -08:00
Taehee Yoo
61fbf5933d net: bpfilter: restart bpfilter_umh when error occurred
The bpfilter_umh will be stopped via __stop_umh() when the bpfilter
error occurred.
The bpfilter_umh() couldn't start again because there is no restart
routine.

The section of the bpfilter_umh_{start/end} is no longer .init.rodata
because these area should be reused in the restart routine. hence
the section name is changed to .bpfilter_umh.

The bpfilter_ops->start() is restart callback. it will be called when
bpfilter_umh is stopped.
The stop bit means bpfilter_umh is stopped. this bit is set by both
start and stop routine.

Before this patch,
Test commands:
   $ iptables -vnL
   $ kill -9 <pid of bpfilter_umh>
   $ iptables -vnL
   [  480.045136] bpfilter: write fail -32
   $ iptables -vnL

All iptables commands will fail.

After this patch,
Test commands:
   $ iptables -vnL
   $ kill -9 <pid of bpfilter_umh>
   $ iptables -vnL
   $ iptables -vnL

Now, all iptables commands will work.

Fixes: d2ba09c17a ("net: add skeleton of bpfilter kernel module")
Signed-off-by: Taehee Yoo <ap420073@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-01-11 18:05:41 -08:00
Taehee Yoo
5b4cb650e5 net: bpfilter: use cleanup callback to release umh_info
Now, UMH process is killed, do_exit() calls the umh_info->cleanup callback
to release members of the umh_info.
This patch makes bpfilter_umh's cleanup routine to use the
umh_info->cleanup callback.

Signed-off-by: Taehee Yoo <ap420073@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-01-11 18:05:41 -08:00
Olivier Brunel
4b78030b8f net: bpfilter: Set user mode helper's command line
Signed-off-by: Olivier Brunel <jjk@jjacky.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-10-22 19:37:36 -07:00
Taehee Yoo
84258438e8 net: bpfilter: use get_pid_task instead of pid_task
pid_task() dereferences rcu protected tasks array.
But there is no rcu_read_lock() in shutdown_umh() routine so that
rcu_read_lock() is needed.
get_pid_task() is wrapper function of pid_task. it holds rcu_read_lock()
then calls pid_task(). if task isn't NULL, it increases reference count
of task.

test commands:
   %modprobe bpfilter
   %modprobe -rv bpfilter

splat looks like:
[15102.030932] =============================
[15102.030957] WARNING: suspicious RCU usage
[15102.030985] 4.19.0-rc7+ #21 Not tainted
[15102.031010] -----------------------------
[15102.031038] kernel/pid.c:330 suspicious rcu_dereference_check() usage!
[15102.031063]
	       other info that might help us debug this:

[15102.031332]
	       rcu_scheduler_active = 2, debug_locks = 1
[15102.031363] 1 lock held by modprobe/1570:
[15102.031389]  #0: 00000000580ef2b0 (bpfilter_lock){+.+.}, at: stop_umh+0x13/0x52 [bpfilter]
[15102.031552]
               stack backtrace:
[15102.031583] CPU: 1 PID: 1570 Comm: modprobe Not tainted 4.19.0-rc7+ #21
[15102.031607] Hardware name: To be filled by O.E.M. To be filled by O.E.M./Aptio CRB, BIOS 5.6.5 07/08/2015
[15102.031628] Call Trace:
[15102.031676]  dump_stack+0xc9/0x16b
[15102.031723]  ? show_regs_print_info+0x5/0x5
[15102.031801]  ? lockdep_rcu_suspicious+0x117/0x160
[15102.031855]  pid_task+0x134/0x160
[15102.031900]  ? find_vpid+0xf0/0xf0
[15102.032017]  shutdown_umh.constprop.1+0x1e/0x53 [bpfilter]
[15102.032055]  stop_umh+0x46/0x52 [bpfilter]
[15102.032092]  __x64_sys_delete_module+0x47e/0x570
[ ... ]

Fixes: d2ba09c17a ("net: add skeleton of bpfilter kernel module")
Signed-off-by: Taehee Yoo <ap420073@gmail.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-10-17 22:03:40 -07:00
Shanthosh RK
33aa8da1f8 net: bpfilter: Fix type cast and pointer warnings
Fixes the following Sparse warnings:

net/bpfilter/bpfilter_kern.c:62:21: warning: cast removes address space
of expression
net/bpfilter/bpfilter_kern.c:101:49: warning: Using plain integer as
NULL pointer

Signed-off-by: Shanthosh RK <shanthosh.rk@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-10-05 11:51:06 -07:00
Linus Torvalds
9a76aba02a Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next
Pull networking updates from David Miller:
 "Highlights:

   - Gustavo A. R. Silva keeps working on the implicit switch fallthru
     changes.

   - Support 802.11ax High-Efficiency wireless in cfg80211 et al, From
     Luca Coelho.

   - Re-enable ASPM in r8169, from Kai-Heng Feng.

   - Add virtual XFRM interfaces, which avoids all of the limitations of
     existing IPSEC tunnels. From Steffen Klassert.

   - Convert GRO over to use a hash table, so that when we have many
     flows active we don't traverse a long list during accumluation.

   - Many new self tests for routing, TC, tunnels, etc. Too many
     contributors to mention them all, but I'm really happy to keep
     seeing this stuff.

   - Hardware timestamping support for dpaa_eth/fsl-fman from Yangbo Lu.

   - Lots of cleanups and fixes in L2TP code from Guillaume Nault.

   - Add IPSEC offload support to netdevsim, from Shannon Nelson.

   - Add support for slotting with non-uniform distribution to netem
     packet scheduler, from Yousuk Seung.

   - Add UDP GSO support to mlx5e, from Boris Pismenny.

   - Support offloading of Team LAG in NFP, from John Hurley.

   - Allow to configure TX queue selection based upon RX queue, from
     Amritha Nambiar.

   - Support ethtool ring size configuration in aquantia, from Anton
     Mikaev.

   - Support DSCP and flowlabel per-transport in SCTP, from Xin Long.

   - Support list based batching and stack traversal of SKBs, this is
     very exciting work. From Edward Cree.

   - Busyloop optimizations in vhost_net, from Toshiaki Makita.

   - Introduce the ETF qdisc, which allows time based transmissions. IGB
     can offload this in hardware. From Vinicius Costa Gomes.

   - Add parameter support to devlink, from Moshe Shemesh.

   - Several multiplication and division optimizations for BPF JIT in
     nfp driver, from Jiong Wang.

   - Lots of prepatory work to make more of the packet scheduler layer
     lockless, when possible, from Vlad Buslov.

   - Add ACK filter and NAT awareness to sch_cake packet scheduler, from
     Toke Høiland-Jørgensen.

   - Support regions and region snapshots in devlink, from Alex Vesker.

   - Allow to attach XDP programs to both HW and SW at the same time on
     a given device, with initial support in nfp. From Jakub Kicinski.

   - Add TLS RX offload and support in mlx5, from Ilya Lesokhin.

   - Use PHYLIB in r8169 driver, from Heiner Kallweit.

   - All sorts of changes to support Spectrum 2 in mlxsw driver, from
     Ido Schimmel.

   - PTP support in mv88e6xxx DSA driver, from Andrew Lunn.

   - Make TCP_USER_TIMEOUT socket option more accurate, from Jon
     Maxwell.

   - Support for templates in packet scheduler classifier, from Jiri
     Pirko.

   - IPV6 support in RDS, from Ka-Cheong Poon.

   - Native tproxy support in nf_tables, from Máté Eckl.

   - Maintain IP fragment queue in an rbtree, but optimize properly for
     in-order frags. From Peter Oskolkov.

   - Improvde handling of ACKs on hole repairs, from Yuchung Cheng"

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (1996 commits)
  bpf: test: fix spelling mistake "REUSEEPORT" -> "REUSEPORT"
  hv/netvsc: Fix NULL dereference at single queue mode fallback
  net: filter: mark expected switch fall-through
  xen-netfront: fix warn message as irq device name has '/'
  cxgb4: Add new T5 PCI device ids 0x50af and 0x50b0
  net: dsa: mv88e6xxx: missing unlock on error path
  rds: fix building with IPV6=m
  inet/connection_sock: prefer _THIS_IP_ to current_text_addr
  net: dsa: mv88e6xxx: bitwise vs logical bug
  net: sock_diag: Fix spectre v1 gadget in __sock_diag_cmd()
  ieee802154: hwsim: using right kind of iteration
  net: hns3: Add vlan filter setting by ethtool command -K
  net: hns3: Set tx ring' tc info when netdev is up
  net: hns3: Remove tx ring BD len register in hns3_enet
  net: hns3: Fix desc num set to default when setting channel
  net: hns3: Fix for phy link issue when using marvell phy driver
  net: hns3: Fix for information of phydev lost problem when down/up
  net: hns3: Fix for command format parsing error in hclge_is_all_function_id_zero
  net: hns3: Add support for serdes loopback selftest
  bnxt_en: take coredump_record structure off stack
  ...
2018-08-15 15:04:25 -07:00
Stephen Hemminger
a17922def7 bpfilter: remove trailing newline
Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-07-24 14:10:42 -07:00
Laura Abbott
b90a368000 kbuild: Rename HOSTLDFLAGS to KBUILD_HOSTLDFLAGS
In preparation for enabling command line LDFLAGS, re-name HOSTLDFLAGS
to KBUILD_HOSTLDFLAGS as the internal use only flags. This should not
have any visible effects.

Signed-off-by: Laura Abbott <labbott@redhat.com>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-07-18 01:18:05 +09:00
Laura Abbott
96f14fe738 kbuild: Rename HOSTCFLAGS to KBUILD_HOSTCFLAGS
In preparation for enabling command line CFLAGS, re-name HOSTCFLAGS to
KBUILD_HOSTCFLAGS as the internal use only flags. This should not have
any visible effects.

Signed-off-by: Laura Abbott <labbott@redhat.com>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-07-18 01:18:05 +09:00
Masahiro Yamada
8e75887d32 bpfilter: include bpfilter_umh in assembly instead of using objcopy
What we want here is to embed a user-space program into the kernel.
Instead of the complex ELF magic, let's simply wrap it in the assembly
with the '.incbin' directive.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-06-28 21:39:16 +09:00
Masahiro Yamada
88e85a7daf bpfilter: check compiler capability in Kconfig
With the brand-new syntax extension of Kconfig, we can directly
check the compiler capability in the configuration phase.

If the cc-can-link.sh fails, the BPFILTER_UMH is automatically
hidden by the dependency.

I also deleted 'default n', which is no-op.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-06-28 13:36:39 +09:00
Matteo Croce
c24fb5e68e bpfilter: fix user mode helper cross compilation
Use $(OBJDUMP) instead of literal 'objdump' to avoid
using host toolchain when cross compiling.

Fixes: 421780fd49 ("bpfilter: fix build error")
Signed-off-by: Matteo Croce <mcroce@redhat.com>
Reported-by: Stefano Brivio <sbrivio@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-06-21 09:19:19 +09:00
Matteo Croce
8b26a06ad4 bpfilter: ignore binary files
net/bpfilter/bpfilter_umh is a binary file generated when bpfilter is
enabled, add it to .gitignore to avoid committing it.

Fixes: d2ba09c17a ("net: add skeleton of bpfilter kernel module")
Signed-off-by: Matteo Croce <mcroce@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-06-20 09:07:46 +09:00
Matteo Croce
421780fd49 bpfilter: fix build error
bpfilter Makefile assumes that the system locale is en_US, and the
parsing of objdump output fails.
Set LC_ALL=C and, while at it, rewrite the objdump parsing so it spawns
only 2 processes instead of 7.

Fixes: d2ba09c17a ("net: add skeleton of bpfilter kernel module")
Signed-off-by: Matteo Croce <mcroce@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-06-20 09:07:46 +09:00
Alexei Starovoitov
66e58e0ef8 bpfilter: fix race in pipe access
syzbot reported the following crash
[  338.293946] bpfilter: read fail -512
[  338.304515] kasan: GPF could be caused by NULL-ptr deref or user memory access
[  338.311863] general protection fault: 0000 [#1] SMP KASAN
[  338.344360] RIP: 0010:__vfs_write+0x4a6/0x960
[  338.426363] Call Trace:
[  338.456967]  __kernel_write+0x10c/0x380
[  338.460928]  __bpfilter_process_sockopt+0x1d8/0x35b
[  338.487103]  bpfilter_mbox_request+0x4d/0xb0
[  338.491492]  bpfilter_ip_get_sockopt+0x6b/0x90

This can happen when multiple cpus trying to talk to user mode process
via bpfilter_mbox_request(). One cpu grabs the mutex while another goes to
sleep on the same mutex. Then former cpu sees that umh pipe is down and
shuts down the pipes. Later cpu finally acquires the mutex and crashes
on freed pipe.
Fix the race by using info.pid as an indicator that umh and pipes are healthy
and check it after acquiring the mutex.

Fixes: d2ba09c17a ("net: add skeleton of bpfilter kernel module")
Reported-by: syzbot+7ade6c94abb2774c0fee@syzkaller.appspotmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-06-07 20:07:28 -04:00
Alexei Starovoitov
8d97ca6b67 bpfilter: fix OUTPUT_FORMAT
CONFIG_OUTPUT_FORMAT is x86 only macro.
Used objdump to extract elf file format.

Fixes: d2ba09c17a ("net: add skeleton of bpfilter kernel module")
Reported-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-06-07 16:56:48 -04:00
Alexei Starovoitov
819dd92b9c bpfilter: switch to CC from HOSTCC
check that CC can build executables and use that compiler instead of HOSTCC

Suggested-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-06-05 10:21:18 -04:00
YueHaibing
ae40832e53 bpfilter: fix a build err
gcc-7.3.0 report following err:

  HOSTCC  net/bpfilter/main.o
In file included from net/bpfilter/main.c:9:0:
./include/uapi/linux/bpf.h:12:10: fatal error: linux/bpf_common.h: No such file or directory
 #include <linux/bpf_common.h>

remove it by adding a include path.
Fixes: d2ba09c17a ("net: add skeleton of bpfilter kernel module")

Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-05-29 15:20:21 -04:00
Arnd Bergmann
d71dbdaa2d bpfilter: fix building without CONFIG_INET
bpfilter_process_sockopt is a callback that gets called from
ip_setsockopt() and ip_getsockopt(). However, when CONFIG_INET is
disabled, it never gets called at all, and assigning a function to the
callback pointer results in a link failure:

net/bpfilter/bpfilter_kern.o: In function `__stop_umh':
bpfilter_kern.c:(.text.unlikely+0x3): undefined reference to `bpfilter_process_sockopt'
net/bpfilter/bpfilter_kern.o: In function `load_umh':
bpfilter_kern.c:(.init.text+0x73): undefined reference to `bpfilter_process_sockopt'

Since there is no caller in this configuration, I assume we can
simply make the assignment conditional.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-05-29 08:13:35 -04:00
Jakub Kicinski
13405468f4 bpfilter: don't pass O_CREAT when opening console for debug
Passing O_CREAT (00000100) to open means we should also pass file
mode as the third parameter.  Creating /dev/console as a regular
file may not be helpful anyway, so simply drop the flag when
opening debug_fd.

Fixes: d2ba09c17a ("net: add skeleton of bpfilter kernel module")
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-05-24 09:36:49 -04:00
Alexei Starovoitov
61a552eb48 bpfilter: fix build dependency
BPFILTER could have been enabled without INET causing this build error:
ERROR: "bpfilter_process_sockopt" [net/bpfilter/bpfilter.ko] undefined!

Fixes: d2ba09c17a ("net: add skeleton of bpfilter kernel module")
Reported-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-05-24 09:33:28 -04:00
Alexei Starovoitov
d2ba09c17a net: add skeleton of bpfilter kernel module
bpfilter.ko consists of bpfilter_kern.c (normal kernel module code)
and user mode helper code that is embedded into bpfilter.ko

The steps to build bpfilter.ko are the following:
- main.c is compiled by HOSTCC into the bpfilter_umh elf executable file
- with quite a bit of objcopy and Makefile magic the bpfilter_umh elf file
  is converted into bpfilter_umh.o object file
  with _binary_net_bpfilter_bpfilter_umh_start and _end symbols
  Example:
  $ nm ./bld_x64/net/bpfilter/bpfilter_umh.o
  0000000000004cf8 T _binary_net_bpfilter_bpfilter_umh_end
  0000000000004cf8 A _binary_net_bpfilter_bpfilter_umh_size
  0000000000000000 T _binary_net_bpfilter_bpfilter_umh_start
- bpfilter_umh.o and bpfilter_kern.o are linked together into bpfilter.ko

bpfilter_kern.c is a normal kernel module code that calls
the fork_usermode_blob() helper to execute part of its own data
as a user mode process.

Notice that _binary_net_bpfilter_bpfilter_umh_start - end
is placed into .init.rodata section, so it's freed as soon as __init
function of bpfilter.ko is finished.
As part of __init the bpfilter.ko does first request/reply action
via two unix pipe provided by fork_usermode_blob() helper to
make sure that umh is healthy. If not it will kill it via pid.

Later bpfilter_process_sockopt() will be called from bpfilter hooks
in get/setsockopt() to pass iptable commands into umh via bpfilter.ko

If admin does 'rmmod bpfilter' the __exit code bpfilter.ko will
kill umh as well.

Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-05-23 13:23:40 -04:00