Commit Graph

992 Commits

Author SHA1 Message Date
Daniel T. Lee
3677d0a131 samples: bpf: Refactor kprobe tracing programs with libbpf
For the problem of increasing fragmentation of the bpf loader programs,
instead of using bpf_loader.o, which is used in samples/bpf, this
commit refactors the existing kprobe tracing programs with libbbpf
bpf loader.

    - For kprobe events pointing to system calls, the SYSCALL() macro in
    trace_common.h was used.
    - Adding a kprobe event and attaching a bpf program to it was done
    through bpf_program_attach().
    - Instead of using the existing BPF MAP definition, MAP definition
    has been refactored with the new BTF-defined MAP format.

Signed-off-by: Daniel T. Lee <danieltimlee@gmail.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200823085334.9413-3-danieltimlee@gmail.com
2020-08-24 20:59:35 -07:00
Daniel T. Lee
35a8b6dd33 samples: bpf: Cleanup bpf_load.o from Makefile
Since commit cc7f641d63 ("samples: bpf: Refactor BPF map performance
test with libbpf") has ommited the removal of bpf_load.o from Makefile,
this commit removes the bpf_load.o rule for targets where bpf_load.o is
not used.

Fixes: cc7f641d63 ("samples: bpf: Refactor BPF map performance test with libbpf")
Signed-off-by: Daniel T. Lee <danieltimlee@gmail.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200823085334.9413-2-danieltimlee@gmail.com
2020-08-24 20:59:35 -07:00
Daniel T. Lee
2bf8c7e735 samples: bpf: Fix broken bpf programs due to removed symbol
>From commit f1394b7988 ("block: mark blk_account_io_completion
static") symbol blk_account_io_completion() has been marked as static,
which makes it no longer possible to attach kprobe to this event.
Currently, there are broken samples due to this reason.

As a solution to this, attach kprobe events to blk_account_io_done()
to modify them to perform the same behavior as before.

Signed-off-by: Daniel T. Lee <danieltimlee@gmail.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20200818051641.21724-1-danieltimlee@gmail.com
2020-08-18 17:10:03 -07:00
Linus Torvalds
fc80c51fd4 Kbuild updates for v5.9
- run the checker (e.g. sparse) after the compiler
 
  - remove unneeded cc-option tests for old compiler flags
 
  - fix tar-pkg to install dtbs
 
  - introduce ccflags-remove-y and asflags-remove-y syntax
 
  - allow to trace functions in sub-directories of lib/
 
  - introduce hostprogs-always-y and userprogs-always-y syntax
 
  - various Makefile cleanups
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Merge tag 'kbuild-v5.9' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild

Pull Kbuild updates from Masahiro Yamada:

 - run the checker (e.g. sparse) after the compiler

 - remove unneeded cc-option tests for old compiler flags

 - fix tar-pkg to install dtbs

 - introduce ccflags-remove-y and asflags-remove-y syntax

 - allow to trace functions in sub-directories of lib/

 - introduce hostprogs-always-y and userprogs-always-y syntax

 - various Makefile cleanups

* tag 'kbuild-v5.9' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild:
  kbuild: stop filtering out $(GCC_PLUGINS_CFLAGS) from cc-option base
  kbuild: include scripts/Makefile.* only when relevant CONFIG is enabled
  kbuild: introduce hostprogs-always-y and userprogs-always-y
  kbuild: sort hostprogs before passing it to ifneq
  kbuild: move host .so build rules to scripts/gcc-plugins/Makefile
  kbuild: Replace HTTP links with HTTPS ones
  kbuild: trace functions in subdirectories of lib/
  kbuild: introduce ccflags-remove-y and asflags-remove-y
  kbuild: do not export LDFLAGS_vmlinux
  kbuild: always create directories of targets
  powerpc/boot: add DTB to 'targets'
  kbuild: buildtar: add dtbs support
  kbuild: remove cc-option test of -ffreestanding
  kbuild: remove cc-option test of -fno-stack-protector
  Revert "kbuild: Create directory for target DTB"
  kbuild: run the checker after the compiler
2020-08-09 14:10:26 -07:00
Masahiro Yamada
faabed295c kbuild: introduce hostprogs-always-y and userprogs-always-y
To build host programs, you need to add the program names to 'hostprogs'
to use the necessary build rule, but it is not enough to build them
because there is no dependency.

There are two types of host programs: built as the prerequisite of
another (e.g. gen_crc32table in lib/Makefile), or always built when
Kbuild visits the Makefile (e.g. genksyms in scripts/genksyms/Makefile).

The latter is typical in Makefiles under scripts/, which contains host
programs globally used during the kernel build. To build them, you need
to add them to both 'hostprogs' and 'always-y'.

This commit adds hostprogs-always-y as a shorthand.

The same applies to user programs. net/bpfilter/Makefile builds
bpfilter_umh on demand, hence always-y is unneeded. In contrast,
programs under samples/ are added to both 'userprogs' and 'always-y'
so they are always built when Kbuild visits the Makefiles.

userprogs-always-y works as a shorthand.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Acked-by: Miguel Ojeda <miguel.ojeda.sandonis@gmail.com>
2020-08-10 01:32:59 +09:00
Linus Torvalds
049eb096da pci-v5.9-changes
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Merge tag 'pci-v5.9-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci

Pull PCI updates from Bjorn Helgaas:
 "Enumeration:
   - Fix pci_cfg_wait queue locking problem (Bjorn Helgaas)
   - Convert PCIe capability PCIBIOS errors to errno (Bolarinwa Olayemi
     Saheed)
   - Align PCIe capability and PCI accessor return values (Bolarinwa
     Olayemi Saheed)
   - Fix pci_create_slot() reference count leak (Qiushi Wu)
   - Announce device after early fixups (Tiezhu Yang)

  PCI device hotplug:
   - Make rpadlpar functions static (Wei Yongjun)

  Driver binding:
   - Add device even if driver attach failed (Rajat Jain)

  Virtualization:
   - xen: Remove redundant initialization of irq (Colin Ian King)

  IOMMU:
   - Add pci_pri_supported() to check device or associated PF (Ashok Raj)
   - Release IVRS table in AMD ACS quirk (Hanjun Guo)
   - Mark AMD Navi10 GPU rev 0x00 ATS as broken (Kai-Heng Feng)
   - Treat "external-facing" devices themselves as internal (Rajat Jain)

  MSI:
   - Forward MSI-X error code in pci_alloc_irq_vectors_affinity() (Piotr
     Stankiewicz)

  Error handling:
   - Clear PCIe Device Status errors only if OS owns AER (Jonathan
     Cameron)
   - Log correctable errors as warning, not error (Matt Jolly)
   - Use 'pci_channel_state_t' instead of 'enum pci_channel_state' (Luc
     Van Oostenryck)

  Peer-to-peer DMA:
   - Allow P2PDMA on AMD Zen and newer CPUs (Logan Gunthorpe)

  ASPM:
   - Add missing newline in sysfs 'policy' (Xiongfeng Wang)

  Native PCIe controllers:
   - Convert to devm_platform_ioremap_resource_byname() (Dejin Zheng)
   - Convert to devm_platform_ioremap_resource() (Dejin Zheng)
   - Remove duplicate error message from devm_pci_remap_cfg_resource()
     callers (Dejin Zheng)
   - Fix runtime PM imbalance on error (Dinghao Liu)
   - Remove dev_err() when handing an error from platform_get_irq()
     (Krzysztof Wilczyński)
   - Use pci_host_bridge.windows list directly instead of splicing in a
     temporary list for cadence, mvebu, host-common (Rob Herring)
   - Use pci_host_probe() instead of open-coding all the pieces for
     altera, brcmstb, iproc, mobiveil, rcar, rockchip, tegra, v3,
     versatile, xgene, xilinx, xilinx-nwl (Rob Herring)
   - Default host bridge parent device to the platform device (Rob
     Herring)
   - Use pci_is_root_bus() instead of tracking root bus number
     separately in aardvark, designware (imx6, keystone,
     designware-host), mobiveil, xilinx-nwl, xilinx, rockchip, rcar (Rob
     Herring)
   - Set host bridge bus number in pci_scan_root_bus_bridge() instead of
     each driver for aardvark, designware-host, host-common, mediatek,
     rcar, tegra, v3-semi (Rob Herring)
   - Move DT resource setup into devm_pci_alloc_host_bridge() (Rob
     Herring)
   - Set bridge map_irq and swizzle_irq to default functions; drivers
     that don't support legacy IRQs (iproc) need to undo this (Rob
     Herring)

  ARM Versatile PCIe controller driver:
   - Drop flag PCI_ENABLE_PROC_DOMAINS (Rob Herring)

  Cadence PCIe controller driver:
   - Use "dma-ranges" instead of "cdns,no-bar-match-nbits" property
     (Kishon Vijay Abraham I)
   - Remove "mem" from reg binding (Kishon Vijay Abraham I)
   - Fix cdns_pcie_{host|ep}_setup() error path (Kishon Vijay Abraham I)
   - Convert all r/w accessors to perform only 32-bit accesses (Kishon
     Vijay Abraham I)
   - Add support to start link and verify link status (Kishon Vijay
     Abraham I)
   - Allow pci_host_bridge to have custom pci_ops (Kishon Vijay Abraham I)
   - Add new *ops* for CPU addr fixup (Kishon Vijay Abraham I)
   - Fix updating Vendor ID and Subsystem Vendor ID register (Kishon
     Vijay Abraham I)
   - Use bridge resources for outbound window setup (Rob Herring)
   - Remove private bus number and range storage (Rob Herring)

  Cadence PCIe endpoint driver:
   - Add MSI-X support (Alan Douglas)

  HiSilicon PCIe controller driver:
   - Remove non-ECAM HiSilicon hip05/hip06 driver (Rob Herring)

  Intel VMD host bridge driver:
   - Use Shadow MEMBAR registers for QEMU/KVM guests (Jon Derrick)

  Loongson PCIe controller driver:
   - Use DECLARE_PCI_FIXUP_EARLY for bridge_class_quirk() (Tiezhu Yang)

  Marvell Aardvark PCIe controller driver:
   - Indicate error in 'val' when config read fails (Pali Rohár)
   - Don't touch PCIe registers if no card connected (Pali Rohár)

  Marvell MVEBU PCIe controller driver:
   - Setup BAR0 in order to fix MSI (Shmuel Hazan)

  Microsoft Hyper-V host bridge driver:
   - Fix a timing issue which causes kdump to fail occasionally (Wei Hu)
   - Make some functions static (Wei Yongjun)

  NVIDIA Tegra PCIe controller driver:
   - Revert tegra124 raw_violation_fixup (Nicolas Chauvet)
   - Remove PLL power supplies (Thierry Reding)

  Qualcomm PCIe controller driver:
   - Change duplicate PCI reset to phy reset (Abhishek Sahu)
   - Add missing ipq806x clocks in PCIe driver (Ansuel Smith)
   - Add missing reset for ipq806x (Ansuel Smith)
   - Add ext reset (Ansuel Smith)
   - Use bulk clk API and assert on error (Ansuel Smith)
   - Add support for tx term offset for rev 2.1.0 (Ansuel Smith)
   - Define some PARF params needed for ipq8064 SoC (Ansuel Smith)
   - Add ipq8064 rev2 variant (Ansuel Smith)
   - Support PCI speed set for ipq806x (Sham Muthayyan)

  Renesas R-Car PCIe controller driver:
   - Use devm_pci_alloc_host_bridge() (Rob Herring)
   - Use struct pci_host_bridge.windows list directly (Rob Herring)
   - Convert rcar-gen2 to use modern host bridge probe functions (Rob
     Herring)

  TI J721E PCIe driver:
   - Add TI J721E PCIe host and endpoint driver (Kishon Vijay Abraham I)

  Xilinx Versal CPM PCIe controller driver:
   - Add Versal CPM Root Port driver and YAML schema (Bharat Kumar
     Gogada)

  MicroSemi Switchtec management driver:
   - Add missing __iomem and __user tags to fix sparse warnings (Logan
     Gunthorpe)

  Miscellaneous:
   - Replace http:// links with https:// (Alexander A. Klimov)
   - Replace lkml.org, spinics, gmane with lore.kernel.org (Bjorn
     Helgaas)
   - Remove unused pci_lost_interrupt() (Heiner Kallweit)
   - Move PCI_VENDOR_ID_REDHAT definition to pci_ids.h (Huacai Chen)
   - Fix kerneldoc warnings (Krzysztof Kozlowski)"

* tag 'pci-v5.9-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci: (113 commits)
  PCI: Fix kerneldoc warnings
  PCI: xilinx-cpm: Add Versal CPM Root Port driver
  PCI: xilinx-cpm: Add YAML schemas for Versal CPM Root Port
  PCI: Set bridge map_irq and swizzle_irq to default functions
  PCI: Move DT resource setup into devm_pci_alloc_host_bridge()
  PCI: rcar-gen2: Convert to use modern host bridge probe functions
  PCI: Remove dev_err() when handing an error from platform_get_irq()
  MAINTAINERS: Add Kishon Vijay Abraham I for TI J721E SoC PCIe
  misc: pci_endpoint_test: Add J721E in pci_device_id table
  PCI: j721e: Add TI J721E PCIe driver
  PCI: switchtec: Add missing __iomem tag to fix sparse warnings
  PCI: switchtec: Add missing __iomem and __user tags to fix sparse warnings
  PCI: rpadlpar: Make functions static
  PCI/P2PDMA: Allow P2PDMA on AMD Zen and newer CPUs
  PCI: Release IVRS table in AMD ACS quirk
  PCI: Announce device after early fixups
  PCI: Mark AMD Navi10 GPU rev 0x00 ATS as broken
  PCI: Remove unused pci_lost_interrupt()
  dt-bindings: PCI: Add EP mode dt-bindings for TI's J721E SoC
  dt-bindings: PCI: Add host mode dt-bindings for TI's J721E SoC
  ...
2020-08-07 18:48:15 -07:00
Linus Torvalds
47ec5303d7 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next
Pull networking updates from David Miller:

 1) Support 6Ghz band in ath11k driver, from Rajkumar Manoharan.

 2) Support UDP segmentation in code TSO code, from Eric Dumazet.

 3) Allow flashing different flash images in cxgb4 driver, from Vishal
    Kulkarni.

 4) Add drop frames counter and flow status to tc flower offloading,
    from Po Liu.

 5) Support n-tuple filters in cxgb4, from Vishal Kulkarni.

 6) Various new indirect call avoidance, from Eric Dumazet and Brian
    Vazquez.

 7) Fix BPF verifier failures on 32-bit pointer arithmetic, from
    Yonghong Song.

 8) Support querying and setting hardware address of a port function via
    devlink, use this in mlx5, from Parav Pandit.

 9) Support hw ipsec offload on bonding slaves, from Jarod Wilson.

10) Switch qca8k driver over to phylink, from Jonathan McDowell.

11) In bpftool, show list of processes holding BPF FD references to
    maps, programs, links, and btf objects. From Andrii Nakryiko.

12) Several conversions over to generic power management, from Vaibhav
    Gupta.

13) Add support for SO_KEEPALIVE et al. to bpf_setsockopt(), from Dmitry
    Yakunin.

14) Various https url conversions, from Alexander A. Klimov.

15) Timestamping and PHC support for mscc PHY driver, from Antoine
    Tenart.

16) Support bpf iterating over tcp and udp sockets, from Yonghong Song.

17) Support 5GBASE-T i40e NICs, from Aleksandr Loktionov.

18) Add kTLS RX HW offload support to mlx5e, from Tariq Toukan.

19) Fix the ->ndo_start_xmit() return type to be netdev_tx_t in several
    drivers. From Luc Van Oostenryck.

20) XDP support for xen-netfront, from Denis Kirjanov.

21) Support receive buffer autotuning in MPTCP, from Florian Westphal.

22) Support EF100 chip in sfc driver, from Edward Cree.

23) Add XDP support to mvpp2 driver, from Matteo Croce.

24) Support MPTCP in sock_diag, from Paolo Abeni.

25) Commonize UDP tunnel offloading code by creating udp_tunnel_nic
    infrastructure, from Jakub Kicinski.

26) Several pci_ --> dma_ API conversions, from Christophe JAILLET.

27) Add FLOW_ACTION_POLICE support to mlxsw, from Ido Schimmel.

28) Add SK_LOOKUP bpf program type, from Jakub Sitnicki.

29) Refactor a lot of networking socket option handling code in order to
    avoid set_fs() calls, from Christoph Hellwig.

30) Add rfc4884 support to icmp code, from Willem de Bruijn.

31) Support TBF offload in dpaa2-eth driver, from Ioana Ciornei.

32) Support XDP_REDIRECT in qede driver, from Alexander Lobakin.

33) Support PCI relaxed ordering in mlx5 driver, from Aya Levin.

34) Support TCP syncookies in MPTCP, from Flowian Westphal.

35) Fix several tricky cases of PMTU handling wrt. briding, from Stefano
    Brivio.

* git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (2056 commits)
  net: thunderx: initialize VF's mailbox mutex before first usage
  usb: hso: remove bogus check for EINPROGRESS
  usb: hso: no complaint about kmalloc failure
  hso: fix bailout in error case of probe
  ip_tunnel_core: Fix build for archs without _HAVE_ARCH_IPV6_CSUM
  selftests/net: relax cpu affinity requirement in msg_zerocopy test
  mptcp: be careful on subflow creation
  selftests: rtnetlink: make kci_test_encap() return sub-test result
  selftests: rtnetlink: correct the final return value for the test
  net: dsa: sja1105: use detected device id instead of DT one on mismatch
  tipc: set ub->ifindex for local ipv6 address
  ipv6: add ipv6_dev_find()
  net: openvswitch: silence suspicious RCU usage warning
  Revert "vxlan: fix tos value before xmit"
  ptp: only allow phase values lower than 1 period
  farsync: switch from 'pci_' to 'dma_' API
  wan: wanxl: switch from 'pci_' to 'dma_' API
  hv_netvsc: do not use VF device if link is down
  dpaa2-eth: Fix passing zero to 'PTR_ERR' warning
  net: macb: Properly handle phylink on at91sam9x
  ...
2020-08-05 20:13:21 -07:00
Linus Torvalds
2324d50d05 It's been a busy cycle for documentation - hopefully the busiest for a
while to come.  Changes include:
 
  - Some new Chinese translations
 
  - Progress on the battle against double words words and non-HTTPS URLs
 
  - Some block-mq documentation
 
  - More RST conversions from Mauro.  At this point, that task is
    essentially complete, so we shouldn't see this kind of churn again for a
    while.  Unless we decide to switch to asciidoc or something...:)
 
  - Lots of typo fixes, warning fixes, and more.
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Merge tag 'docs-5.9' of git://git.lwn.net/linux

Pull documentation updates from Jonathan Corbet:
 "It's been a busy cycle for documentation - hopefully the busiest for a
  while to come. Changes include:

   - Some new Chinese translations

   - Progress on the battle against double words words and non-HTTPS
     URLs

   - Some block-mq documentation

   - More RST conversions from Mauro. At this point, that task is
     essentially complete, so we shouldn't see this kind of churn again
     for a while. Unless we decide to switch to asciidoc or
     something...:)

   - Lots of typo fixes, warning fixes, and more"

* tag 'docs-5.9' of git://git.lwn.net/linux: (195 commits)
  scripts/kernel-doc: optionally treat warnings as errors
  docs: ia64: correct typo
  mailmap: add entry for <alobakin@marvell.com>
  doc/zh_CN: add cpu-load Chinese version
  Documentation/admin-guide: tainted-kernels: fix spelling mistake
  MAINTAINERS: adjust kprobes.rst entry to new location
  devices.txt: document rfkill allocation
  PCI: correct flag name
  docs: filesystems: vfs: correct flag name
  docs: filesystems: vfs: correct sync_mode flag names
  docs: path-lookup: markup fixes for emphasis
  docs: path-lookup: more markup fixes
  docs: path-lookup: fix HTML entity mojibake
  CREDITS: Replace HTTP links with HTTPS ones
  docs: process: Add an example for creating a fixes tag
  doc/zh_CN: add Chinese translation prefer section
  doc/zh_CN: add clearing-warn-once Chinese version
  doc/zh_CN: add admin-guide index
  doc:it_IT: process: coding-style.rst: Correct __maybe_unused compiler label
  futex: MAINTAINERS: Re-add selftests directory
  ...
2020-08-04 22:47:54 -07:00
Ilya Leoshkevich
e4d9c23207 samples/bpf, selftests/bpf: Use bpf_probe_read_kernel
A handful of samples and selftests fail to build on s390, because
after commit 0ebeea8ca8 ("bpf: Restrict bpf_probe_read{, str}()
only to archs where they work") bpf_probe_read is not available
anymore.

Fix by using bpf_probe_read_kernel.

Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200720114806.88823-1-iii@linux.ibm.com
2020-07-21 13:26:26 -07:00
Lorenzo Bianconi
ce4dade7f1 samples/bpf: xdp_redirect_cpu: Load a eBPF program on cpumap
Extend xdp_redirect_cpu_{usr,kern}.c adding the possibility to load
a XDP program on cpumap entries. The following options have been added:
- mprog-name: cpumap entry program name
- mprog-filename: cpumap entry program filename
- redirect-device: output interface if the cpumap program performs a
  XDP_REDIRECT to an egress interface
- redirect-map: bpf map used to perform XDP_REDIRECT to an egress
  interface
- mprog-disable: disable loading XDP program on cpumap entries

Add xdp_pass, xdp_drop, xdp_redirect stats accounting

Co-developed-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/aa5a9a281b9dac425620fdabe82670ffb6bbdb92.1594734381.git.lorenzo@kernel.org
2020-07-16 17:00:32 +02:00
Lorenzo Bianconi
a4e76f1bda samples/bpf: xdp_redirect_cpu_user: Do not update bpf maps in option loop
Do not update xdp_redirect_cpu maps running while option loop but
defer it after all available options have been parsed. This is a
preliminary patch to pass the program name we want to attach to the
map entries as a user option

Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Jesper Dangaard Brouer <brouer@redhat.com>
Link: https://lore.kernel.org/bpf/95dc46286fd2c609042948e04bb7ae1f5b425538.1594734381.git.lorenzo@kernel.org
2020-07-16 17:00:31 +02:00
David S. Miller
07dd1b7e68 Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next
Alexei Starovoitov says:

====================
pull-request: bpf-next 2020-07-13

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

We've added 36 non-merge commits during the last 7 day(s) which contain
a total of 62 files changed, 2242 insertions(+), 468 deletions(-).

The main changes are:

1) Avoid trace_printk warning banner by switching bpf_trace_printk to use
   its own tracing event, from Alan.

2) Better libbpf support on older kernels, from Andrii.

3) Additional AF_XDP stats, from Ciara.

4) build time resolution of BTF IDs, from Jiri.

5) BPF_CGROUP_INET_SOCK_RELEASE hook, from Stanislav.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2020-07-13 18:04:05 -07:00
Ciara Loftus
b36c3206f9 samples: bpf: Add an option for printing extra statistics in xdpsock
Introduce the --extra-stats (or simply -x) flag to the xdpsock application
which prints additional statistics alongside the regular rx and tx
counters. The new statistics printed report error conditions eg. rx ring
full, invalid descriptors, etc.

Signed-off-by: Ciara Loftus <ciara.loftus@intel.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200708072835.4427-3-ciara.loftus@intel.com
2020-07-13 15:32:56 -07:00
Wenbo Zhang
eef8a42d6c bpf: Fix fds_example SIGSEGV error
The `BPF_LOG_BUF_SIZE`'s value is `UINT32_MAX >> 8`, so define an array
with it on stack caused an overflow.

Signed-off-by: Wenbo Zhang <ethercflow@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/20200710092035.28919-1-ethercflow@gmail.com
2020-07-10 23:25:25 +02:00
Huacai Chen
2575b2f3ee PCI: Move PCI_VENDOR_ID_REDHAT definition to pci_ids.h
Instead of duplicating the PCI_VENDOR_ID_REDHAT definition everywhere, move
it to include/linux/pci_ids.h.

[bhelgaas: also update MDPY_PCI_VENDOR_ID]
Link: https://lore.kernel.org/r/1594195170-11119-1-git-send-email-chenhc@lemote.com
Signed-off-by: Huacai Chen <chenhc@lemote.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Gerd Hoffmann <kraxel@redhat.com>
2020-07-09 17:00:47 -05:00
Daniel T. Lee
cc7f641d63 samples: bpf: Refactor BPF map performance test with libbpf
Previously, in order to set the numa_node attribute at the time of map
creation using "libbpf", it was necessary to call bpf_create_map_node()
directly (bpf_load approach), instead of calling bpf_object_load()
that handles everything on its own, including map creation. And because
of this problem, this sample had problems with refactoring from bpf_load
to libbbpf.

However, by commit 1bdb6c9a1c ("libbpf: Add a bunch of attribute
getters/setters for map definitions") added the numa_node attribute and
allowed it to be set in the map.

By using libbpf instead of bpf_load, the inner map definition has
been explicitly declared with BTF-defined format. Also, the element of
ARRAY_OF_MAPS was also statically specified using the BTF format. And
for this reason some logic in fixup_map() was not needed and changed
or removed.

Signed-off-by: Daniel T. Lee <danieltimlee@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/20200707184855.30968-4-danieltimlee@gmail.com
2020-07-08 01:33:14 +02:00
Daniel T. Lee
88795b4adb samples: bpf: Refactor BPF map in map test with libbpf
From commit 646f02ffdd ("libbpf: Add BTF-defined map-in-map
support"), a way to define internal map in BTF-defined map has been
added.

Instead of using previous 'inner_map_idx' definition, the structure to
be used for the inner map can be directly defined using array directive.

    __array(values, struct inner_map)

This commit refactors map in map test program with libbpf by explicitly
defining inner map with BTF-defined format.

Signed-off-by: Daniel T. Lee <danieltimlee@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/20200707184855.30968-3-danieltimlee@gmail.com
2020-07-08 01:33:10 +02:00
Daniel T. Lee
af9bd3e333 samples: bpf: Fix bpf programs with kprobe/sys_connect event
Currently, BPF programs with kprobe/sys_connect does not work properly.

Commit 34745aed51 ("samples/bpf: fix kprobe attachment issue on x64")
This commit modifies the bpf_load behavior of kprobe events in the x64
architecture. If the current kprobe event target starts with "sys_*",
add the prefix "__x64_" to the front of the event.

Appending "__x64_" prefix with kprobe/sys_* event was appropriate as a
solution to most of the problems caused by the commit below.

    commit d5a00528b5 ("syscalls/core, syscalls/x86: Rename struct
    pt_regs-based sys_*() to __x64_sys_*()")

However, there is a problem with the sys_connect kprobe event that does
not work properly. For __sys_connect event, parameters can be fetched
normally, but for __x64_sys_connect, parameters cannot be fetched.

    ffffffff818d3520 <__x64_sys_connect>:
    ffffffff818d3520: e8 fb df 32 00        callq   0xffffffff81c01520
    <__fentry__>
    ffffffff818d3525: 48 8b 57 60           movq    96(%rdi), %rdx
    ffffffff818d3529: 48 8b 77 68           movq    104(%rdi), %rsi
    ffffffff818d352d: 48 8b 7f 70           movq    112(%rdi), %rdi
    ffffffff818d3531: e8 1a ff ff ff        callq   0xffffffff818d3450
    <__sys_connect>
    ffffffff818d3536: 48 98                 cltq
    ffffffff818d3538: c3                    retq
    ffffffff818d3539: 0f 1f 80 00 00 00 00  nopl    (%rax)

As the assembly code for __x64_sys_connect shows, parameters should be
fetched and set into rdi, rsi, rdx registers prior to calling
__sys_connect.

Because of this problem, this commit fixes the sys_connect event by
first getting the value of the rdi register and then the value of the
rdi, rsi, and rdx register through an offset based on that value.

Fixes: 34745aed51 ("samples/bpf: fix kprobe attachment issue on x64")
Signed-off-by: Daniel T. Lee <danieltimlee@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/20200707184855.30968-2-danieltimlee@gmail.com
2020-07-08 01:32:14 +02:00
Kees Cook
c3eeaae9fd samples/vfs: avoid warning in statx override
Something changed recently to uncover this warning:

  samples/vfs/test-statx.c:24:15: warning: `struct foo' declared inside parameter list will not be visible outside of this definition or declaration
     24 | #define statx foo
        |               ^~~

Which is due the use of "struct statx" (here, "struct foo") in a function
prototype argument list before it has been defined:

 int
 # 56 "/usr/include/x86_64-linux-gnu/bits/statx-generic.h"
    foo
 # 56 "/usr/include/x86_64-linux-gnu/bits/statx-generic.h" 3 4
          (int __dirfd, const char *__restrict __path, int __flags,
            unsigned int __mask, struct
 # 57 "/usr/include/x86_64-linux-gnu/bits/statx-generic.h"
                                       foo
 # 57 "/usr/include/x86_64-linux-gnu/bits/statx-generic.h" 3 4
                                             *__restrict __buf)
   __attribute__ ((__nothrow__ , __leaf__)) __attribute__ ((__nonnull__ (2, 5)));

Add explicit struct before #include to avoid warning.

Fixes: f1b5618e01 ("vfs: Add a sample program for the new mount API")
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Miklos Szeredi <mszeredi@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: David Howells <dhowells@redhat.com>
Link: http://lkml.kernel.org/r/202006282213.C516EA6@keescook
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-07-03 16:15:25 -07:00
Linus Torvalds
4a21185cda Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Pull networking fixes from David Miller:

 1) Don't insert ESP trailer twice in IPSEC code, from Huy Nguyen.

 2) The default crypto algorithm selection in Kconfig for IPSEC is out
    of touch with modern reality, fix this up. From Eric Biggers.

 3) bpftool is missing an entry for BPF_MAP_TYPE_RINGBUF, from Andrii
    Nakryiko.

 4) Missing init of ->frame_sz in xdp_convert_zc_to_xdp_frame(), from
    Hangbin Liu.

 5) Adjust packet alignment handling in ax88179_178a driver to match
    what the hardware actually does. From Jeremy Kerr.

 6) register_netdevice can leak in the case one of the notifiers fail,
    from Yang Yingliang.

 7) Use after free in ip_tunnel_lookup(), from Taehee Yoo.

 8) VLAN checks in sja1105 DSA driver need adjustments, from Vladimir
    Oltean.

 9) tg3 driver can sleep forever when we get enough EEH errors, fix from
    David Christensen.

10) Missing {READ,WRITE}_ONCE() annotations in various Intel ethernet
    drivers, from Ciara Loftus.

11) Fix scanning loop break condition in of_mdiobus_register(), from
    Florian Fainelli.

12) MTU limit is incorrect in ibmveth driver, from Thomas Falcon.

13) Endianness fix in mlxsw, from Ido Schimmel.

14) Use after free in smsc95xx usbnet driver, from Tuomas Tynkkynen.

15) Missing bridge mrp configuration validation, from Horatiu Vultur.

16) Fix circular netns references in wireguard, from Jason A. Donenfeld.

17) PTP initialization on recovery is not done properly in qed driver,
    from Alexander Lobakin.

18) Endian conversion of L4 ports in filters of cxgb4 driver is wrong,
    from Rahul Lakkireddy.

19) Don't clear bound device TX queue of socket prematurely otherwise we
    get problems with ktls hw offloading, from Tariq Toukan.

20) ipset can do atomics on unaligned memory, fix from Russell King.

21) Align ethernet addresses properly in bridging code, from Thomas
    Martitz.

22) Don't advertise ipv4 addresses on SCTP sockets having ipv6only set,
    from Marcelo Ricardo Leitner.

* git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (149 commits)
  rds: transport module should be auto loaded when transport is set
  sch_cake: fix a few style nits
  sch_cake: don't call diffserv parsing code when it is not needed
  sch_cake: don't try to reallocate or unshare skb unconditionally
  ethtool: fix error handling in linkstate_prepare_data()
  wil6210: account for napi_gro_receive never returning GRO_DROP
  hns: do not cast return value of napi_gro_receive to null
  socionext: account for napi_gro_receive never returning GRO_DROP
  wireguard: receive: account for napi_gro_receive never returning GRO_DROP
  vxlan: fix last fdb index during dump of fdb with nhid
  sctp: Don't advertise IPv4 addresses if ipv6only is set on the socket
  tc-testing: avoid action cookies with odd length.
  bpf: tcp: bpf_cubic: fix spurious HYSTART_DELAY exit upon drop in min RTT
  tcp_cubic: fix spurious HYSTART_DELAY exit upon drop in min RTT
  net: dsa: sja1105: fix tc-gate schedule with single element
  net: dsa: sja1105: recalculate gating subschedule after deleting tc-gate rules
  net: dsa: sja1105: unconditionally free old gating config
  net: dsa: sja1105: move sja1105_compose_gating_subschedule at the top
  net: macb: free resources on failure path of at91ether_open()
  net: macb: call pm_runtime_put_sync on failure path
  ...
2020-06-25 18:27:40 -07:00
Linus Torvalds
be9160a90d Kbuild fixes for v5.8
- fix -gz=zlib compiler option test for CONFIG_DEBUG_INFO_COMPRESSED
 
  - improve cc-option in scripts/Kbuild.include to clean up temp files
 
  - improve cc-option in scripts/Kconfig.include for more reliable compile
    option test
 
  - do not copy modules.builtin by 'make install' because it would break
    existing systems
 
  - use 'userprogs' syntax for watch_queue sample
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Merge tag 'kbuild-fixes-v5.8' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild

Pull Kbuild fixes from Masahiro Yamada:

 - fix -gz=zlib compiler option test for CONFIG_DEBUG_INFO_COMPRESSED

 - improve cc-option in scripts/Kbuild.include to clean up temp files

 - improve cc-option in scripts/Kconfig.include for more reliable
   compile option test

 - do not copy modules.builtin by 'make install' because it would break
   existing systems

 - use 'userprogs' syntax for watch_queue sample

* tag 'kbuild-fixes-v5.8' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild:
  samples: watch_queue: build sample program for target architecture
  Revert "Makefile: install modules.builtin even if CONFIG_MODULES=n"
  scripts: Fix typo in headers_install.sh
  kconfig: unify cc-option and as-option
  kbuild: improve cc-option to clean up all temporary files
  Makefile: Improve compressed debug info support detection
2020-06-21 12:44:52 -07:00
Masahiro Yamada
214377e9b7 samples: watch_queue: build sample program for target architecture
This userspace program includes UAPI headers exported to usr/include/.
'make headers' always works for the target architecture (i.e. the same
architecture as the kernel), so the sample program should be built for
the target as well. Kbuild now supports 'userprogs' for that.

I also guarded the CONFIG option by 'depends on CC_CAN_LINK' because
$(CC) may not provide libc.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-06-22 01:56:09 +09:00
Linus Torvalds
8b6ddd10d6 A few fixes and small cleanups for tracing:
- Have recordmcount work with > 64K sections (to support LTO)
  - kprobe RCU fixes
  - Correct a kprobe critical section with missing mutex
  - Remove redundant arch_disarm_kprobe() call
  - Fix lockup when kretprobe triggers within kprobe_flush_task()
  - Fix memory leak in fetch_op_data operations
  - Fix sleep in atomic in ftrace trace array sample code
  - Free up memory on failure in sample trace array code
  - Fix incorrect reporting of function_graph fields in format file
  - Fix quote within quote parsing in bootconfig
  - Fix return value of bootconfig tool
  - Add testcases for bootconfig tool
  - Fix maybe uninitialized warning in ftrace pid file code
  - Remove unused variable in tracing_iter_reset()
  - Fix some typos
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Merge tag 'trace-v5.8-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

Pull tracing fixes from Steven Rostedt:

 - Have recordmcount work with > 64K sections (to support LTO)

 - kprobe RCU fixes

 - Correct a kprobe critical section with missing mutex

 - Remove redundant arch_disarm_kprobe() call

 - Fix lockup when kretprobe triggers within kprobe_flush_task()

 - Fix memory leak in fetch_op_data operations

 - Fix sleep in atomic in ftrace trace array sample code

 - Free up memory on failure in sample trace array code

 - Fix incorrect reporting of function_graph fields in format file

 - Fix quote within quote parsing in bootconfig

 - Fix return value of bootconfig tool

 - Add testcases for bootconfig tool

 - Fix maybe uninitialized warning in ftrace pid file code

 - Remove unused variable in tracing_iter_reset()

 - Fix some typos

* tag 'trace-v5.8-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  ftrace: Fix maybe-uninitialized compiler warning
  tools/bootconfig: Add testcase for show-command and quotes test
  tools/bootconfig: Fix to return 0 if succeeded to show the bootconfig
  tools/bootconfig: Fix to use correct quotes for value
  proc/bootconfig: Fix to use correct quotes for value
  tracing: Remove unused event variable in tracing_iter_reset
  tracing/probe: Fix memleak in fetch_op_data operations
  trace: Fix typo in allocate_ftrace_ops()'s comment
  tracing: Make ftrace packed events have align of 1
  sample-trace-array: Remove trace_array 'sample-instance'
  sample-trace-array: Fix sleeping function called from invalid context
  kretprobe: Prevent triggering kretprobe from within kprobe_flush_task
  kprobes: Remove redundant arch_disarm_kprobe() call
  kprobes: Fix to protect kick_kprobe_optimizer() by kprobe_mutex
  kprobes: Use non RCU traversal APIs on kprobe_tables if possible
  kprobes: Suppress the suspicious RCU warning on kprobes
  recordmcount: support >64k sections
2020-06-20 13:17:47 -07:00
Mauro Carvalho Chehab
8e2a46a40f docs: move remaining stuff under Documentation/*.txt to Documentation/staging
There are several files that I was unable to find a proper place
for them, and 3 ones that are still in plain old text format.

Let's place those stuff behind the carpet, as we'd like to keep the
root directory clean.

We can later discuss and move those into better places.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Link: https://lore.kernel.org/r/11bd0d75e65a874f7c276a0aeab0fe13f3376f5f.1592203650.git.mchehab+huawei@kernel.org
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2020-06-19 14:17:05 -06:00
David S. Miller
b9d37bbb55 Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf
Alexei Starovoitov says:

====================
pull-request: bpf 2020-06-17

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

We've added 10 non-merge commits during the last 2 day(s) which contain
a total of 14 files changed, 158 insertions(+), 59 deletions(-).

The main changes are:

1) Important fix for bpf_probe_read_kernel_str() return value, from Andrii.

2) [gs]etsockopt fix for large optlen, from Stanislav.

3) devmap allocation fix, from Toke.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2020-06-17 13:26:55 -07:00
Kefeng Wang
9fbc01cdba sample-trace-array: Remove trace_array 'sample-instance'
Remove trace_array 'sample-instance' if kthread_run fails
in sample_trace_array_init().

Link: https://lkml.kernel.org/r/20200609135200.2206726-1-wangkefeng.wang@huawei.com

Cc: stable@vger.kernel.org
Fixes: 89ed42495e ("tracing: Sample module to demonstrate kernel access to Ftrace instances.")
Reviewed-by: Divya Indi <divya.indi@oracle.com>
Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2020-06-16 21:21:02 -04:00
Kefeng Wang
e9b7b1c0c1 sample-trace-array: Fix sleeping function called from invalid context
BUG: sleeping function called from invalid context at kernel/locking/mutex.c:935
 in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 0, name: swapper/5
 1 lock held by swapper/5/0:
  #0: ffff80001002bd90 (samples/ftrace/sample-trace-array.c:38){+.-.}-{0:0}, at: call_timer_fn+0x8/0x3e0
 CPU: 5 PID: 0 Comm: swapper/5 Not tainted 5.7.0+ #8
 Hardware name: QEMU QEMU Virtual Machine, BIOS 0.0.0 02/06/2015
 Call trace:
  dump_backtrace+0x0/0x1a0
  show_stack+0x20/0x30
  dump_stack+0xe4/0x150
  ___might_sleep+0x160/0x200
  __might_sleep+0x58/0x90
  __mutex_lock+0x64/0x948
  mutex_lock_nested+0x3c/0x58
  __ftrace_set_clr_event+0x44/0x88
  trace_array_set_clr_event+0x24/0x38
  mytimer_handler+0x34/0x40 [sample_trace_array]

mutex_lock() will be called in interrupt context, using workqueue to fix it.

Link: https://lkml.kernel.org/r/20200610011244.2209486-1-wangkefeng.wang@huawei.com

Cc: stable@vger.kernel.org
Fixes: 89ed42495e ("tracing: Sample module to demonstrate kernel access to Ftrace instances.")
Reviewed-by: Divya Indi <divya.indi@oracle.com>
Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2020-06-16 21:21:02 -04:00
Gaurav Singh
6903cdae9f bpf, xdp, samples: Fix null pointer dereference in *_user code
Memset on the pointer right after malloc can cause a NULL pointer
deference if it failed to allocate memory. A simple fix is to
replace malloc()/memset() pair with a simple call to calloc().

Fixes: 0fca931a6f ("samples/bpf: program demonstrating access to xdp_rxq_info")
Signed-off-by: Gaurav Singh <gaurav1086@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Jesper Dangaard Brouer <brouer@redhat.com>
Acked-by: John Fastabend <john.fastabend@gmail.com>
2020-06-16 14:55:35 +02:00
Gustavo A. R. Silva
f2baaff279 samples: mei: Replace zero-length array with flexible-array
There is a regular need in the kernel to provide a way to declare having a
dynamically sized set of trailing elements in a structure. Kernel code should
always use “flexible array members”[1] for these cases. The older style of
one-element or zero-length arrays should no longer be used[2].

[1] https://en.wikipedia.org/wiki/Flexible_array_member
[2] https://github.com/KSPP/linux/issues/21

Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
2020-06-15 23:08:31 -05:00
Linus Torvalds
4f9b3a3775 binderfs: add gitignore for generated sample program
Let's keep "git status" happy and quiet.

Fixes: 9762dc1432 ("samples: add binderfs sample program
Fixes: fca5e94921 ("samples: binderfs: really compile this sample and fix build issues")
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-13 13:41:24 -07:00
Linus Torvalds
6adc19fd13 Kbuild updates for v5.8 (2nd)
- fix build rules in binderfs sample
 
  - fix build errors when Kbuild recurses to the top Makefile
 
  - covert '---help---' in Kconfig to 'help'
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Merge tag 'kbuild-v5.8-2' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild

Pull more Kbuild updates from Masahiro Yamada:

 - fix build rules in binderfs sample

 - fix build errors when Kbuild recurses to the top Makefile

 - covert '---help---' in Kconfig to 'help'

* tag 'kbuild-v5.8-2' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild:
  treewide: replace '---help---' in Kconfig files with 'help'
  kbuild: fix broken builds because of GZIP,BZIP2,LZOP variables
  samples: binderfs: really compile this sample and fix build issues
2020-06-13 13:29:16 -07:00
Linus Torvalds
298ce0fd50 watch_queue: add gitignore for generated sample program
Let's keep "git status" happy and quiet.

Fixes: f5b5a164f9 ("Add sample notification program")
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-13 13:00:54 -07:00
Linus Torvalds
6c32978414 Notifications over pipes + Keyring notifications
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Merge tag 'notifications-20200601' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs

Pull notification queue from David Howells:
 "This adds a general notification queue concept and adds an event
  source for keys/keyrings, such as linking and unlinking keys and
  changing their attributes.

  Thanks to Debarshi Ray, we do have a pull request to use this to fix a
  problem with gnome-online-accounts - as mentioned last time:

     https://gitlab.gnome.org/GNOME/gnome-online-accounts/merge_requests/47

  Without this, g-o-a has to constantly poll a keyring-based kerberos
  cache to find out if kinit has changed anything.

  [ There are other notification pending: mount/sb fsinfo notifications
    for libmount that Karel Zak and Ian Kent have been working on, and
    Christian Brauner would like to use them in lxc, but let's see how
    this one works first ]

  LSM hooks are included:

   - A set of hooks are provided that allow an LSM to rule on whether or
     not a watch may be set. Each of these hooks takes a different
     "watched object" parameter, so they're not really shareable. The
     LSM should use current's credentials. [Wanted by SELinux & Smack]

   - A hook is provided to allow an LSM to rule on whether or not a
     particular message may be posted to a particular queue. This is
     given the credentials from the event generator (which may be the
     system) and the watch setter. [Wanted by Smack]

  I've provided SELinux and Smack with implementations of some of these
  hooks.

  WHY
  ===

  Key/keyring notifications are desirable because if you have your
  kerberos tickets in a file/directory, your Gnome desktop will monitor
  that using something like fanotify and tell you if your credentials
  cache changes.

  However, we also have the ability to cache your kerberos tickets in
  the session, user or persistent keyring so that it isn't left around
  on disk across a reboot or logout. Keyrings, however, cannot currently
  be monitored asynchronously, so the desktop has to poll for it - not
  so good on a laptop. This facility will allow the desktop to avoid the
  need to poll.

  DESIGN DECISIONS
  ================

   - The notification queue is built on top of a standard pipe. Messages
     are effectively spliced in. The pipe is opened with a special flag:

        pipe2(fds, O_NOTIFICATION_PIPE);

     The special flag has the same value as O_EXCL (which doesn't seem
     like it will ever be applicable in this context)[?]. It is given up
     front to make it a lot easier to prohibit splice&co from accessing
     the pipe.

     [?] Should this be done some other way?  I'd rather not use up a new
         O_* flag if I can avoid it - should I add a pipe3() system call
         instead?

     The pipe is then configured::

        ioctl(fds[1], IOC_WATCH_QUEUE_SET_SIZE, queue_depth);
        ioctl(fds[1], IOC_WATCH_QUEUE_SET_FILTER, &filter);

     Messages are then read out of the pipe using read().

   - It should be possible to allow write() to insert data into the
     notification pipes too, but this is currently disabled as the
     kernel has to be able to insert messages into the pipe *without*
     holding pipe->mutex and the code to make this work needs careful
     auditing.

   - sendfile(), splice() and vmsplice() are disabled on notification
     pipes because of the pipe->mutex issue and also because they
     sometimes want to revert what they just did - but one or more
     notification messages might've been interleaved in the ring.

   - The kernel inserts messages with the wait queue spinlock held. This
     means that pipe_read() and pipe_write() have to take the spinlock
     to update the queue pointers.

   - Records in the buffer are binary, typed and have a length so that
     they can be of varying size.

     This allows multiple heterogeneous sources to share a common
     buffer; there are 16 million types available, of which I've used
     just a few, so there is scope for others to be used. Tags may be
     specified when a watchpoint is created to help distinguish the
     sources.

   - Records are filterable as types have up to 256 subtypes that can be
     individually filtered. Other filtration is also available.

   - Notification pipes don't interfere with each other; each may be
     bound to a different set of watches. Any particular notification
     will be copied to all the queues that are currently watching for it
     - and only those that are watching for it.

   - When recording a notification, the kernel will not sleep, but will
     rather mark a queue as having lost a message if there's
     insufficient space. read() will fabricate a loss notification
     message at an appropriate point later.

   - The notification pipe is created and then watchpoints are attached
     to it, using one of:

        keyctl_watch_key(KEY_SPEC_SESSION_KEYRING, fds[1], 0x01);
        watch_mount(AT_FDCWD, "/", 0, fd, 0x02);
        watch_sb(AT_FDCWD, "/mnt", 0, fd, 0x03);

     where in both cases, fd indicates the queue and the number after is
     a tag between 0 and 255.

   - Watches are removed if either the notification pipe is destroyed or
     the watched object is destroyed. In the latter case, a message will
     be generated indicating the enforced watch removal.

  Things I want to avoid:

   - Introducing features that make the core VFS dependent on the
     network stack or networking namespaces (ie. usage of netlink).

   - Dumping all this stuff into dmesg and having a daemon that sits
     there parsing the output and distributing it as this then puts the
     responsibility for security into userspace and makes handling
     namespaces tricky. Further, dmesg might not exist or might be
     inaccessible inside a container.

   - Letting users see events they shouldn't be able to see.

  TESTING AND MANPAGES
  ====================

   - The keyutils tree has a pipe-watch branch that has keyctl commands
     for making use of notifications. Proposed manual pages can also be
     found on this branch, though a couple of them really need to go to
     the main manpages repository instead.

     If the kernel supports the watching of keys, then running "make
     test" on that branch will cause the testing infrastructure to spawn
     a monitoring process on the side that monitors a notifications pipe
     for all the key/keyring changes induced by the tests and they'll
     all be checked off to make sure they happened.

        https://git.kernel.org/pub/scm/linux/kernel/git/dhowells/keyutils.git/log/?h=pipe-watch

   - A test program is provided (samples/watch_queue/watch_test) that
     can be used to monitor for keyrings, mount and superblock events.
     Information on the notifications is simply logged to stdout"

* tag 'notifications-20200601' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs:
  smack: Implement the watch_key and post_notification hooks
  selinux: Implement the watch_key security hook
  keys: Make the KEY_NEED_* perms an enum rather than a mask
  pipe: Add notification lossage handling
  pipe: Allow buffers to be marked read-whole-or-error for notifications
  Add sample notification program
  watch_queue: Add a key/keyring notification facility
  security: Add hooks to rule on setting a watch
  pipe: Add general notification queue support
  pipe: Add O_NOTIFICATION_PIPE
  security: Add a hook for the point of notification insertion
  uapi: General notification queue definitions
2020-06-13 09:56:21 -07:00
Masahiro Yamada
fca5e94921 samples: binderfs: really compile this sample and fix build issues
Even after commit c624adc9cb ("samples: fix binderfs sample"), this
sample is never compiled.

'hostprogs' teaches Kbuild that this is a host program, but not enough
to order to compile it. You must add it to 'always-y' to really compile
it.

Since this sample has never been compiled in upstream, various issues
are left unnoticed.

[1] compilers without <linux/android/binderfs.h> are still widely used

<linux/android/binderfs.h> is only available since commit c13295ad21
("binderfs: rename header to binderfs.h"), i.e., Linux 5.0

If your compiler is based on UAPI headers older than Linux 5.0, you
will see the following error:

  samples/binderfs/binderfs_example.c:16:10: fatal error: linux/android/binderfs.h: No such file or directory
   #include <linux/android/binderfs.h>
            ^~~~~~~~~~~~~~~~~~~~~~~~~~
  compilation terminated.

You cannot rely on compilers having such a new header.

The common approach is to install UAPI headers of this kernel into
usr/include, and then add it to the header search path.

I added 'depends on HEADERS_INSTALL' in Kconfig, and '-I usr/include'
compiler flag in Makefile.

[2] compile the sample for target architecture

Because headers_install works for the target architecture, only the
native compiler was able to build sample code that requires
'-I usr/include'.

Commit 7f3a59db27 ("kbuild: add infrastructure to build userspace
programs") added the new syntax 'userprogs' to compile user-space
programs for the target architecture.

Use it, and then 'ifndef CROSS_COMPILE' will go away.

I added 'depends on CC_CAN_LINK' because $(CC) is not necessarily
capable of linking user-space programs.

[3] use subdir-y to descend into samples/binderfs

Since this directory does not contain any kernel-space code, it has no
point in generating built-in.a or modules.order.

Replace obj-$(CONFIG_...) with subdir-$(CONFIG_...).

[4] -Wunused-variable warning

If I compile this, I see the following warning.

  samples/binderfs/binderfs_example.c: In function 'main':
  samples/binderfs/binderfs_example.c:21:9: warning: unused variable 'len' [-Wunused-variable]
     21 |  size_t len;
        |         ^~~

I removed the unused 'len'.

[5] CONFIG_ANDROID_BINDERFS is not required

Since this is a user-space standalone program, it is independent of
the kernel configuration.

Remove 'depends on ANDROID_BINDERFS'.

Fixes: 9762dc1432 ("samples: add binderfs sample program")
Fixes: c624adc9cb ("samples: fix binderfs sample")
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Acked-by: Christian Brauner <christian.brauner@ubuntu.com>
2020-06-11 20:14:41 +09:00
Linus Torvalds
cff11abeca Kbuild updates for v5.8
- fix warnings in 'make clean' for ARCH=um, hexagon, h8300, unicore32
 
  - ensure to rebuild all objects when the compiler is upgraded
 
  - exclude system headers from dependency tracking and fixdep processing
 
  - fix potential bit-size mismatch between the kernel and BPF user-mode
    helper
 
  - add the new syntax 'userprogs' to build user-space programs for the
    target architecture (the same arch as the kernel)
 
  - compile user-space sample code under samples/ for the target arch
    instead of the host arch
 
  - make headers_install fail if a CONFIG option is leaked to user-space
 
  - sanitize the output format of scripts/checkstack.pl
 
  - handle ARM 'push' instruction in scripts/checkstack.pl
 
  - error out before modpost if a module name conflict is found
 
  - error out when multiple directories are passed to M= because this
    feature is broken for a long time
 
  - add CONFIG_DEBUG_INFO_COMPRESSED to support compressed debug info
 
  - a lot of cleanups of modpost
 
  - dump vmlinux symbols out into vmlinux.symvers, and reuse it in the
    second pass of modpost
 
  - do not run the second pass of modpost if nothing in modules is updated
 
  - install modules.builtin(.modinfo) by 'make install' as well as by
    'make modules_install' because it is useful even when CONFIG_MODULES=n
 
  - add new command line variables, GZIP, BZIP2, LZOP, LZMA, LZ4, and XZ
    to allow users to use alternatives such as pigz, pbzip2, etc.
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Merge tag 'kbuild-v5.8' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild

Pull Kbuild updates from Masahiro Yamada:

 - fix warnings in 'make clean' for ARCH=um, hexagon, h8300, unicore32

 - ensure to rebuild all objects when the compiler is upgraded

 - exclude system headers from dependency tracking and fixdep processing

 - fix potential bit-size mismatch between the kernel and BPF user-mode
   helper

 - add the new syntax 'userprogs' to build user-space programs for the
   target architecture (the same arch as the kernel)

 - compile user-space sample code under samples/ for the target arch
   instead of the host arch

 - make headers_install fail if a CONFIG option is leaked to user-space

 - sanitize the output format of scripts/checkstack.pl

 - handle ARM 'push' instruction in scripts/checkstack.pl

 - error out before modpost if a module name conflict is found

 - error out when multiple directories are passed to M= because this
   feature is broken for a long time

 - add CONFIG_DEBUG_INFO_COMPRESSED to support compressed debug info

 - a lot of cleanups of modpost

 - dump vmlinux symbols out into vmlinux.symvers, and reuse it in the
   second pass of modpost

 - do not run the second pass of modpost if nothing in modules is
   updated

 - install modules.builtin(.modinfo) by 'make install' as well as by
   'make modules_install' because it is useful even when
   CONFIG_MODULES=n

 - add new command line variables, GZIP, BZIP2, LZOP, LZMA, LZ4, and XZ
   to allow users to use alternatives such as pigz, pbzip2, etc.

* tag 'kbuild-v5.8' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (96 commits)
  kbuild: add variables for compression tools
  Makefile: install modules.builtin even if CONFIG_MODULES=n
  mksysmap: Fix the mismatch of '.L' symbols in System.map
  kbuild: doc: rename LDFLAGS to KBUILD_LDFLAGS
  modpost: change elf_info->size to size_t
  modpost: remove is_vmlinux() helper
  modpost: strip .o from modname before calling new_module()
  modpost: set have_vmlinux in new_module()
  modpost: remove mod->skip struct member
  modpost: add mod->is_vmlinux struct member
  modpost: remove is_vmlinux() call in check_for_{gpl_usage,unused}()
  modpost: remove mod->is_dot_o struct member
  modpost: move -d option in scripts/Makefile.modpost
  modpost: remove -s option
  modpost: remove get_next_text() and make {grab,release_}file static
  modpost: use read_text_file() and get_line() for reading text files
  modpost: avoid false-positive file open error
  modpost: fix potential mmap'ed file overrun in get_src_version()
  modpost: add read_text_file() and get_line() helpers
  modpost: do not call get_modinfo() for vmlinux(.o)
  ...
2020-06-06 12:00:25 -07:00
Linus Torvalds
cb8e59cc87 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next
Pull networking updates from David Miller:

 1) Allow setting bluetooth L2CAP modes via socket option, from Luiz
    Augusto von Dentz.

 2) Add GSO partial support to igc, from Sasha Neftin.

 3) Several cleanups and improvements to r8169 from Heiner Kallweit.

 4) Add IF_OPER_TESTING link state and use it when ethtool triggers a
    device self-test. From Andrew Lunn.

 5) Start moving away from custom driver versions, use the globally
    defined kernel version instead, from Leon Romanovsky.

 6) Support GRO vis gro_cells in DSA layer, from Alexander Lobakin.

 7) Allow hard IRQ deferral during NAPI, from Eric Dumazet.

 8) Add sriov and vf support to hinic, from Luo bin.

 9) Support Media Redundancy Protocol (MRP) in the bridging code, from
    Horatiu Vultur.

10) Support netmap in the nft_nat code, from Pablo Neira Ayuso.

11) Allow UDPv6 encapsulation of ESP in the ipsec code, from Sabrina
    Dubroca. Also add ipv6 support for espintcp.

12) Lots of ReST conversions of the networking documentation, from Mauro
    Carvalho Chehab.

13) Support configuration of ethtool rxnfc flows in bcmgenet driver,
    from Doug Berger.

14) Allow to dump cgroup id and filter by it in inet_diag code, from
    Dmitry Yakunin.

15) Add infrastructure to export netlink attribute policies to
    userspace, from Johannes Berg.

16) Several optimizations to sch_fq scheduler, from Eric Dumazet.

17) Fallback to the default qdisc if qdisc init fails because otherwise
    a packet scheduler init failure will make a device inoperative. From
    Jesper Dangaard Brouer.

18) Several RISCV bpf jit optimizations, from Luke Nelson.

19) Correct the return type of the ->ndo_start_xmit() method in several
    drivers, it's netdev_tx_t but many drivers were using
    'int'. From Yunjian Wang.

20) Add an ethtool interface for PHY master/slave config, from Oleksij
    Rempel.

21) Add BPF iterators, from Yonghang Song.

22) Add cable test infrastructure, including ethool interfaces, from
    Andrew Lunn. Marvell PHY driver is the first to support this
    facility.

23) Remove zero-length arrays all over, from Gustavo A. R. Silva.

24) Calculate and maintain an explicit frame size in XDP, from Jesper
    Dangaard Brouer.

25) Add CAP_BPF, from Alexei Starovoitov.

26) Support terse dumps in the packet scheduler, from Vlad Buslov.

27) Support XDP_TX bulking in dpaa2 driver, from Ioana Ciornei.

28) Add devm_register_netdev(), from Bartosz Golaszewski.

29) Minimize qdisc resets, from Cong Wang.

30) Get rid of kernel_getsockopt and kernel_setsockopt in order to
    eliminate set_fs/get_fs calls. From Christoph Hellwig.

* git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (2517 commits)
  selftests: net: ip_defrag: ignore EPERM
  net_failover: fixed rollback in net_failover_open()
  Revert "tipc: Fix potential tipc_aead refcnt leak in tipc_crypto_rcv"
  Revert "tipc: Fix potential tipc_node refcnt leak in tipc_rcv"
  vmxnet3: allow rx flow hash ops only when rss is enabled
  hinic: add set_channels ethtool_ops support
  selftests/bpf: Add a default $(CXX) value
  tools/bpf: Don't use $(COMPILE.c)
  bpf, selftests: Use bpf_probe_read_kernel
  s390/bpf: Use bcr 0,%0 as tail call nop filler
  s390/bpf: Maintain 8-byte stack alignment
  selftests/bpf: Fix verifier test
  selftests/bpf: Fix sample_cnt shared between two threads
  bpf, selftests: Adapt cls_redirect to call csum_level helper
  bpf: Add csum_level helper for fixing up csum levels
  bpf: Fix up bpf_skb_adjust_room helper's skb csum setting
  sfc: add missing annotation for efx_ef10_try_update_nic_stats_vf()
  crypto/chtls: IPv6 support for inline TLS
  Crypto/chcr: Fixes a coccinile check error
  Crypto/chcr: Fixes compilations warnings
  ...
2020-06-03 16:27:18 -07:00
Linus Torvalds
f359287765 Merge branch 'from-miklos' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull vfs updates from Al Viro:
 "Assorted patches from Miklos.

  An interesting part here is /proc/mounts stuff..."

The "/proc/mounts stuff" is using a cursor for keeeping the location
data while traversing the mount listing.

Also probably worth noting is the addition of faccessat2(), which takes
an additional set of flags to specify how the lookup is done
(AT_EACCESS, AT_SYMLINK_NOFOLLOW, AT_EMPTY_PATH).

* 'from-miklos' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  vfs: add faccessat2 syscall
  vfs: don't parse "silent" option
  vfs: don't parse "posixacl" option
  vfs: don't parse forbidden flags
  statx: add mount_root
  statx: add mount ID
  statx: don't clear STATX_ATIME on SB_RDONLY
  uapi: deprecate STATX_ALL
  utimensat: AT_EMPTY_PATH support
  vfs: split out access_override_creds()
  proc/mounts: add cursor
  aio: fix async fsync creds
  vfs: allow unprivileged whiteout creation
2020-06-01 16:44:06 -07:00
Linus Torvalds
b23c4771ff A fair amount of stuff this time around, dominated by yet another massive
set from Mauro toward the completion of the RST conversion.  I *really*
 hope we are getting close to the end of this.  Meanwhile, those patches
 reach pretty far afield to update document references around the tree;
 there should be no actual code changes there.  There will be, alas, more of
 the usual trivial merge conflicts.
 
 Beyond that we have more translations, improvements to the sphinx
 scripting, a number of additions to the sysctl documentation, and lots of
 fixes.
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Merge tag 'docs-5.8' of git://git.lwn.net/linux

Pull documentation updates from Jonathan Corbet:
 "A fair amount of stuff this time around, dominated by yet another
  massive set from Mauro toward the completion of the RST conversion. I
  *really* hope we are getting close to the end of this. Meanwhile,
  those patches reach pretty far afield to update document references
  around the tree; there should be no actual code changes there. There
  will be, alas, more of the usual trivial merge conflicts.

  Beyond that we have more translations, improvements to the sphinx
  scripting, a number of additions to the sysctl documentation, and lots
  of fixes"

* tag 'docs-5.8' of git://git.lwn.net/linux: (130 commits)
  Documentation: fixes to the maintainer-entry-profile template
  zswap: docs/vm: Fix typo accept_threshold_percent in zswap.rst
  tracing: Fix events.rst section numbering
  docs: acpi: fix old http link and improve document format
  docs: filesystems: add info about efivars content
  Documentation: LSM: Correct the basic LSM description
  mailmap: change email for Ricardo Ribalda
  docs: sysctl/kernel: document unaligned controls
  Documentation: admin-guide: update bug-hunting.rst
  docs: sysctl/kernel: document ngroups_max
  nvdimm: fixes to maintainter-entry-profile
  Documentation/features: Correct RISC-V kprobes support entry
  Documentation/features: Refresh the arch support status files
  Revert "docs: sysctl/kernel: document ngroups_max"
  docs: move locking-specific documents to locking/
  docs: move digsig docs to the security book
  docs: move the kref doc into the core-api book
  docs: add IRQ documentation at the core-api book
  docs: debugging-via-ohci1394.txt: add it to the core-api book
  docs: fix references for ipmi.rst file
  ...
2020-06-01 15:45:27 -07:00
Linus Torvalds
69fc06f70f There are a lot of objtool changes in this cycle, all across the map:
- Speed up objtool significantly, especially when there are large number of sections
  - Improve objtool's understanding of special instructions such as IRET,
    to reduce the number of annotations required
  - Implement 'noinstr' validation
  - Do baby steps for non-x86 objtool use
  - Simplify/fix retpoline decoding
  - Add vmlinux validation
  - Improve documentation
  - Fix various bugs and apply smaller cleanups
 
 Signed-off-by: Ingo Molnar <mingo@kernel.org>
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Merge tag 'objtool-core-2020-06-01' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull objtool updates from Ingo Molnar:
 "There are a lot of objtool changes in this cycle, all across the map:

   - Speed up objtool significantly, especially when there are large
     number of sections

   - Improve objtool's understanding of special instructions such as
     IRET, to reduce the number of annotations required

   - Implement 'noinstr' validation

   - Do baby steps for non-x86 objtool use

   - Simplify/fix retpoline decoding

   - Add vmlinux validation

   - Improve documentation

   - Fix various bugs and apply smaller cleanups"

* tag 'objtool-core-2020-06-01' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (54 commits)
  objtool: Enable compilation of objtool for all architectures
  objtool: Move struct objtool_file into arch-independent header
  objtool: Exit successfully when requesting help
  objtool: Add check_kcov_mode() to the uaccess safelist
  samples/ftrace: Fix asm function ELF annotations
  objtool: optimize add_dead_ends for split sections
  objtool: use gelf_getsymshndx to handle >64k sections
  objtool: Allow no-op CFI ops in alternatives
  x86/retpoline: Fix retpoline unwind
  x86: Change {JMP,CALL}_NOSPEC argument
  x86: Simplify retpoline declaration
  x86/speculation: Change FILL_RETURN_BUFFER to work with objtool
  objtool: Add support for intra-function calls
  objtool: Move the IRET hack into the arch decoder
  objtool: Remove INSN_STACK
  objtool: Make handle_insn_ops() unconditional
  objtool: Rework allocating stack_ops on decode
  objtool: UNWIND_HINT_RET_OFFSET should not check registers
  objtool: is_fentry_call() crashes if call has no destination
  x86,smap: Fix smap_{save,restore}() alternatives
  ...
2020-06-01 13:13:00 -07:00
Linus Torvalds
0bd957eb11 Various kprobes updates, mostly centered around cleaning up the no-instrumentation
logic, instead of the current per debug facility blacklist, use the more generic
 .noinstr.text approach, combined with a 'noinstr' marker for functions.
 
 Also add instrumentation_begin()/end() to better manage the exact place in entry
 code where instrumentation may be used.
 
 Also add a kprobes blacklist for modules.
 
 Signed-off-by: Ingo Molnar <mingo@kernel.org>
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Merge tag 'core-kprobes-2020-06-01' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull kprobes updates from Ingo Molnar:
 "Various kprobes updates, mostly centered around cleaning up the
  no-instrumentation logic.

  Instead of the current per debug facility blacklist, use the more
  generic .noinstr.text approach, combined with a 'noinstr' marker for
  functions.

  Also add instrumentation_begin()/end() to better manage the exact
  place in entry code where instrumentation may be used.

  And add a kprobes blacklist for modules"

* tag 'core-kprobes-2020-06-01' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  kprobes: Prevent probes in .noinstr.text section
  vmlinux.lds.h: Create section for protection against instrumentation
  samples/kprobes: Add __kprobes and NOKPROBE_SYMBOL() for handlers.
  kprobes: Support NOKPROBE_SYMBOL() in modules
  kprobes: Support __kprobes blacklist in modules
  kprobes: Lock kprobe_mutex while showing kprobe_blacklist
2020-06-01 12:45:04 -07:00
Josh Poimboeuf
9d907f1ae8 samples/ftrace: Fix asm function ELF annotations
Enable objtool coverage for the sample ftrace modules by adding ELF
annotations to the asm trampoline functions.

  samples/ftrace/ftrace-direct.o: warning: objtool: .text+0x0: unreachable instruction
  samples/ftrace/ftrace-direct-modify.o: warning: objtool: .text+0x0: unreachable instruction
  samples/ftrace/ftrace-direct-too.o: warning: objtool: .text+0x0: unreachable instruction

Reported-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
2020-05-20 08:30:43 -05:00
Daniel T. Lee
59929cd1fe samples, bpf: Refactor kprobe, tail call kern progs map definition
Because the previous two commit replaced the bpf_load implementation of
the user program with libbpf, the corresponding kernel program's MAP
definition can be replaced with new BTF-defined map syntax.

This commit only updates the samples which uses libbpf API for loading
bpf program not with bpf_load.

Signed-off-by: Daniel T. Lee <danieltimlee@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20200516040608.1377876-6-danieltimlee@gmail.com
2020-05-19 17:13:03 +02:00
Daniel T. Lee
14846dda63 samples, bpf: Add tracex7 test file to .gitignore
This commit adds tracex7 test file (testfile.img) to .gitignore which
comes from test_override_return.sh.

Signed-off-by: Daniel T. Lee <danieltimlee@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20200516040608.1377876-5-danieltimlee@gmail.com
2020-05-19 17:13:00 +02:00
Daniel T. Lee
bc1a85977b samples, bpf: Refactor tail call user progs with libbpf
BPF tail call uses the BPF_MAP_TYPE_PROG_ARRAY type map for calling
into other BPF programs and this PROG_ARRAY should be filled prior to
use. Currently, samples with the PROG_ARRAY type MAP fill this program
array with bpf_load. For bpf_load to fill this map, kernel BPF program
must specify the section with specific format of <prog_type>/<array_idx>
(e.g. SEC("socket/0"))

But by using libbpf instead of bpf_load, user program can specify which
programs should be added to PROG_ARRAY. The advantage of this approach
is that you can selectively add only the programs you want, rather than
adding all of them to PROG_ARRAY, and it's much more intuitive than the
traditional approach.

This commit refactors user programs with the PROG_ARRAY type MAP with
libbpf instead of using bpf_load.

Signed-off-by: Daniel T. Lee <danieltimlee@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20200516040608.1377876-4-danieltimlee@gmail.com
2020-05-19 17:12:56 +02:00
Daniel T. Lee
63841bc083 samples, bpf: Refactor kprobe tracing user progs with libbpf
Currently, the kprobe BPF program attachment method for bpf_load is
quite old. The implementation of bpf_load "directly" controls and
manages(create, delete) the kprobe events of DEBUGFS. On the other hand,
using using the libbpf automatically manages the kprobe event.
(under bpf_link interface)

By calling bpf_program__attach(_kprobe) in libbpf, the corresponding
kprobe is created and the BPF program will be attached to this kprobe.
To remove this, by simply invoking bpf_link__destroy will clean up the
event.

This commit refactors kprobe tracing programs (tracex{1~7}_user.c) with
libbpf using bpf_link interface and bpf_program__attach.

tracex2_kern.c, which tracks system calls (sys_*), has been modified to
append prefix depending on architecture.

Signed-off-by: Daniel T. Lee <danieltimlee@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20200516040608.1377876-3-danieltimlee@gmail.com
2020-05-19 17:12:53 +02:00
Daniel T. Lee
0efdcefb00 samples, bpf: Refactor pointer error check with libbpf
Current method of checking pointer error is not user friendly.
Especially the __must_check define makes this less intuitive.

Since, libbpf has an API libbpf_get_error() which checks pointer error,
this commit refactors existing pointer error check logic with libbpf.

Signed-off-by: Daniel T. Lee <danieltimlee@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20200516040608.1377876-2-danieltimlee@gmail.com
2020-05-19 17:12:49 +02:00
David Howells
e7d553d69c pipe: Add notification lossage handling
Add handling for loss of notifications by having read() insert a
loss-notification message after it has read the pipe buffer that was last
in the ring when the loss occurred.

Lossage can come about either by running out of notification descriptors or
by running out of space in the pipe ring.

Signed-off-by: David Howells <dhowells@redhat.com>
2020-05-19 15:40:28 +01:00
David Howells
8cfba76383 pipe: Allow buffers to be marked read-whole-or-error for notifications
Allow a buffer to be marked such that read() must return the entire buffer
in one go or return ENOBUFS.  Multiple buffers can be amalgamated into a
single read, but a short read will occur if the next "whole" buffer won't
fit.

This is useful for watch queue notifications to make sure we don't split a
notification across multiple reads, especially given that we need to
fabricate an overrun record under some circumstances - and that isn't in
the buffers.

Signed-off-by: David Howells <dhowells@redhat.com>
2020-05-19 15:38:18 +01:00
David Howells
f5b5a164f9 Add sample notification program
The sample program is run like:

	./samples/watch_queue/watch_test

and watches "/" for mount changes and the current session keyring for key
changes:

	# keyctl add user a a @s
	1035096409
	# keyctl unlink 1035096409 @s

producing:

	# ./watch_test
	read() = 16
	NOTIFY[000]: ty=000001 sy=02 i=00000110
	KEY 2ffc2e5d change=2[linked] aux=1035096409
	read() = 16
	NOTIFY[000]: ty=000001 sy=02 i=00000110
	KEY 2ffc2e5d change=3[unlinked] aux=1035096409

Other events may be produced, such as with a failing disk:

	read() = 22
	NOTIFY[000]: ty=000003 sy=02 i=00000416
	USB 3-7.7 dev-reset e=0 r=0
	read() = 24
	NOTIFY[000]: ty=000002 sy=06 i=00000418
	BLOCK 00800050 e=6[critical medium] s=64000ef8

This corresponds to:

	blk_update_request: critical medium error, dev sdf, sector 1677725432 op 0x0:(READ) flags 0x0 phys_seg 1 prio class 0

in dmesg.

Signed-off-by: David Howells <dhowells@redhat.com>
2020-05-19 15:38:07 +01:00
Masahiro Yamada
88a8e278ff samples: watchdog: use 'userprogs' syntax
Kbuild now supports the 'userprogs' syntax to compile userspace
programs for the same architecture as the kernel.

Add the entry to samples/Makefile to put this into the build bot
coverage.

I also added the CONFIG option guarded by 'depends on CC_CAN_LINK'
because $(CC) may not provide libc.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Acked-by: Sam Ravnborg <sam@ravnborg.org>
2020-05-17 18:52:02 +09:00