Commit Graph

24280 Commits

Author SHA1 Message Date
Aaron Lewis
df11f7dd58 selftests: kvm: Fix the segment descriptor layout to match the actual layout
Fix the layout of 'struct desc64' to match the layout described in the
SDM Vol 3, Chapter 3 "Protected-Mode Memory Management", section 3.4.5
"Segment Descriptors", Figure 3-8 "Segment Descriptor".  The test added
later in this series relies on this and crashes if this layout is not
correct.

Signed-off-by: Aaron Lewis <aaronlewis@google.com>
Reviewed-by: Alexander Graf <graf@amazon.com>
Message-Id: <20201012194716.3950330-2-aaronlewis@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-11-08 06:02:13 -05:00
Jakub Kicinski
86bbf01977 Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf
Alexei Starovoitov says:

====================
pull-request: bpf 2020-11-06

1) Pre-allocated per-cpu hashmap needs to zero-fill reused element, from David.

2) Tighten bpf_lsm function check, from KP.

3) Fix bpftool attaching to flow dissector, from Lorenz.

4) Use -fno-gcse for the whole kernel/bpf/core.c instead of function attribute, from Ard.

* git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf:
  bpf: Update verification logic for LSM programs
  bpf: Zero-fill re-used per-cpu map element
  bpf: BPF_PRELOAD depends on BPF_SYSCALL
  tools/bpftool: Fix attaching flow dissector
  libbpf: Fix possible use after free in xsk_socket__delete
  libbpf: Fix null dereference in xsk_socket__delete
  libbpf, hashmap: Fix undefined behavior in hash_bits
  bpf: Don't rely on GCC __attribute__((optimize)) to disable GCSE
  tools, bpftool: Remove two unused variables.
  tools, bpftool: Avoid array index warnings.
  xsk: Fix possible memory leak at socket close
  bpf: Add struct bpf_redir_neigh forward declaration to BPF helper defs
  samples/bpf: Set rlimit for memlock to infinity in all samples
  bpf: Fix -Wshadow warnings
  selftest/bpf: Fix profiler test using CO-RE relocation for enums
====================

Link: https://lore.kernel.org/r/20201106221759.24143-1-alexei.starovoitov@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2020-11-06 17:49:34 -08:00
Jakub Kicinski
ae0d0bb29b Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2020-11-06 17:33:38 -08:00
Paul E. McKenney
b6ff30849c tools/memory-model: Label MP tests' producers and consumers
This commit adds comments that label the MP tests' producer and consumer
processes, and also that label the "exists" clause as the bad outcome.

Reported-by: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2020-11-06 17:25:17 -08:00
Paul E. McKenney
acc4bdc55d tools/memory-model: Use "buf" and "flag" for message-passing tests
The use of "x" and "y" for message-passing tests is fine for people
familiar with memory models and litmus-test nomenclature, but is a bit
obtuse for others.  This commit therefore substitutes "buf" for "x" and
"flag" for "y" for the MP tests.  There are a few special-case MP tests
that use locks and these are unchanged.  There is another MP test that
uses pointers, and this is changed to name the pointer "p".

Reported-by: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2020-11-06 17:25:16 -08:00
Paul E. McKenney
1947bfcf81 tools/memory-model: Add types to litmus tests
This commit adds type information for global variables in the litmus
tests in order to allow easier use with klitmus7.

Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2020-11-06 17:25:16 -08:00
Paul E. McKenney
0a27ce6b69 tools/memory-model: Add a glossary of LKMM terms
[ paulmck: Apply Alan Stern feedback. ]
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2020-11-06 17:24:53 -08:00
Paul E. McKenney
ebb477cb2f tools/memory-model: Document categories of ordering primitives
The Linux kernel has a number of categories of ordering primitives, which
are recorded in the LKMM implementation and hinted at by cheatsheet.txt.
But there is no overview of these categories, and such an overview
is needed in order to understand multithreaded LKMM litmus tests.
This commit therefore adds an ordering.txt as well as extracting a
control-dependencies.txt from memory-barriers.txt.  It also updates the
README file.

[ paulmck:  Apply Akira Yokosawa file-placement feedback. ]
[ paulmck:  Apply Alan Stern feedback. ]
[ paulmck:  Apply self-review feedback. ]
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2020-11-06 17:24:50 -08:00
Anna-Maria Behnsen
01f9e708d9 tools/rcutorture: Fix BUG parsing of console.log
For the rcutorture test summary log file console.log of virtual machines is
parsed. When a console.log contains "DEBUG", BUG counter is incremented
because regular expression does not handle to ignore DEBUG.

Signed-off-by: Anna-Maria Behnsen <anna-maria@linutronix.de>
Reviewed-by: Benedikt Spranger <b.spranger@linutronix.de>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2020-11-06 17:13:58 -08:00
Bhaskar Chowdhury
06dc8d4591 tools/nolibc: Fix a spelling error in a comment
Fix a spelling in the comment line.

s/memry/memory/p

This is on linux-next.

Signed-off-by: Bhaskar Chowdhury <unixbhaskar@gmail.com>
Signed-off-by: Willy Tarreau <w@1wt.eu>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2020-11-06 17:13:58 -08:00
Paul E. McKenney
5be7d80deb torture: Make kvm-check-branches.sh use --allcpus
Currently the kvm-check-branches.sh script calculates the number of CPUs
and passes this to the kvm.sh --cpus command-line argument.  This works,
but this commit saves a line by instead using the new kvm.sh --allcpus
command-line argument.

Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2020-11-06 17:13:58 -08:00
Samuel Hernandez
6c5b9de2c6 rcutorture/nolibc: Fix a typo in header file
This fixes a typo. Before this, the AT_FDCWD macro would be defined
regardless of whether or not it's been defined before.

Signed-off-by: Samuel Hernandez <sam.hernandez.amador@gmail.com>
Signed-off-by: Willy Tarreau <w@1wt.eu>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2020-11-06 17:13:57 -08:00
Paul E. McKenney
a5136f4ffb torture: Allow alternative forms of kvm.sh command-line arguments
This commit allows --build-only as a synonym for --buildonly, --kconfigs
for --kconfig, and --kmake-args for --kmake-arg.

Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2020-11-06 17:13:55 -08:00
Paul E. McKenney
7de1ca3526 torture: Accept time units on kvm.sh --duration argument
The "--duration <minutes>" has worked well for a very long time, but
it can be inconvenient to compute the minutes for (say) a 28-hour run.
It can also be annoying to have to let a simple boot test run for a full
minute.  This commit therefore permits an "s" suffix to specify seconds,
"m" to specify minutes (which remains the default), "h" suffix to specify
hours, and "d" to specify days.

With this change, "--duration 5" still specifies that each scenario
run for five minutes, but "--duration 30s" runs for only 30 seconds,
"--duration 8h" runs for eight hours, and "--duration 2d" runs for
two days.

Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2020-11-06 17:13:55 -08:00
Paul E. McKenney
c1e0628758 torture: Force weak-hashed pointers on console log
Although the rcutorture scripting now deals correctly with full-up
security-induced pointer obfuscation, it is still counter-productive for
kernel hackers who are analyzing console output.  This commit therefore
sets the debug_boot_weak_hash kernel boot parameter, which enables
printing of weak-hashed pointers for torture-test runs.

Please note that this change applies only to runs initiated by the
kvm.sh scripting.  If you are instead using modprobe and rmmod, it is
your responsibility to build and boot the underlying kernel to your taste.

Please note further that this change does not result in a security hole
in normal use.  The rcutorture testing runs with a negligible userspace,
no networking, and no user interaction.  Besides which, there is no data
of value that can be extracted from an rcutorture guest OS that could
not also be extracted from the host that this guest is running on.

Suggested-by: Anna-Maria Gleixner <anna-maria@linutronix.de>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2020-11-06 17:13:54 -08:00
Paul E. McKenney
c64659ef29 torture: Prevent jitter processes from delaying failed run
Even when the kernel panics and qemu dies, runs with jitter enabled will
continue uselessly until the jitter.sh processes terminate.  This can
be annoying if a planned one-hour run instead dies during boot.

This commit therefore kills the jitter.sh processes when the run ends
more than one minute prior to the termination time specified by the
kvm.sh --duration argument or its default.

Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2020-11-06 17:13:53 -08:00
Paul E. McKenney
6f26d010e6 rcutorture: Adjust scenarios SRCU-t and SRCU-u to make kconfig happy
The SRCU-u scenario expects to enable lockdep but to also disable the
CONFIG_PREEMPT_COUNT kconfig option.  This no longer works.  This commit
therefore instead enables lockdep in SRCU-t, which then allows SRCU-u
to disable CONFIG_PREEMPT_COUNT.

Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2020-11-06 17:13:52 -08:00
Paul E. McKenney
8d68e68a78 torture: Exclude "NOHZ tick-stop error" from fatal errors
The "NOHZ tick-stop error: Non-RCU local softirq work is pending"
warning happens frequently and appears to be irrelevant to the various
torture tests.  This commit therefore filters it out.

If there proves to be a need to pay attention to it a later commit will
add an "advice" category to allow the user to immediately see that
although something happened, it was not an indictment of the system
being tortured.

Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2020-11-06 17:13:50 -08:00
Paul E. McKenney
45c7b96201 rcuscale: Avoid divide by zero
The rcuscale test module does not use batches, so there is only
ever one batch.  This commit therefore informs the kvm-recheck-rcuscale.sh
script of this fact of life.

Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2020-11-06 17:13:50 -08:00
Paul E. McKenney
899f317e48 rcuscale: Add RCU Tasks Trace
This commit adds the ability to test performance and scalability of RCU
Tasks Trace updaters.

Reported-by: Alexei Starovoitov <alexei.starovoitov@gmail.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2020-11-06 17:13:50 -08:00
Linus Torvalds
03f0f5ad58 Merge tag 'linux-kselftest-fixes-5.10-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest
Pull Kselftest fixes from Shuah Khan:
 "Fixes to the ftrace test and several fixes from Tommi Rantala for
  various other tests"

* tag 'linux-kselftest-fixes-5.10-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest:
  selftests: binderfs: use SKIP instead of XFAIL
  selftests: clone3: use SKIP instead of XFAIL
  selftests: core: use SKIP instead of XFAIL in close_range_test.c
  selftests: proc: fix warning: _GNU_SOURCE redefined
  selftests: pidfd: drop needless linux/kcmp.h inclusion in pidfd_setns_test.c
  selftests: pidfd: add CONFIG_CHECKPOINT_RESTORE=y to config
  selftests: pidfd: skip test on kcmp() ENOSYS
  selftests: pidfd: use ksft_test_result_skip() when skipping test
  selftests/harness: prettify SKIP message whitespace again
  selftests: pidfd: fix compilation errors due to wait.h
  selftests: filter kselftest headers from command in lib.mk
  selftests/ftrace: check for do_sys_openat2 in user-memory test
  selftests/ftrace: Use $FUNCTION_FORK to reference kernel fork function
2020-11-06 15:42:42 -08:00
Alexei Starovoitov
f055f355fa selftests/bpf: Fix selftest build with old libc
pidfd_open was added in 2019. Some versions of libc library don't define it.
Define it manually if it's not available.

Reported-by: Sergei Iudin <siudin@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2020-11-06 12:33:46 -08:00
Linus Torvalds
41f1653024 Merge tag 'net-5.10-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Pull networking fixes from Jakub Kicinski:
 "Networking fixes for 5.10-rc3, including fixes from wireless, can, and
  netfilter subtrees.

  Current merge window - bugs in new features:

   - can: isotp: isotp_rcv_cf(): enable RX timeout handling in
     listen-only mode

  Previous releases - regressions:

   - mac80211:
      - don't require VHT elements for HE on 2.4 GHz
      - fix regression where EAPOL frames were sent in plaintext

   - netfilter:
      - ipset: Update byte and packet counters regardless of whether
        they match

   - ip_tunnel: fix over-mtu packet send by allowing fragmenting even if
     inner packet has IP_DF (don't fragment) set in its header (when
     TUNNEL_DONT_FRAGMENT flag is not set on the tunnel dev)

   - net: fec: fix MDIO probing for some FEC hardware blocks

   - ip6_tunnel: set inner ipproto before ip6_tnl_encap to un-break gso
     support

   - sctp: Fix COMM_LOST/CANT_STR_ASSOC err reporting on big-endian
     platforms, sparse-related fix used the wrong integer size

  Previous releases - always broken:

   - netfilter: use actual socket sk rather than skb sk when routing
     harder

   - r8169: work around short packet hw bug on RTL8125 by padding frames

   - net: ethernet: ti: cpsw: disable PTPv1 hw timestamping
     advertisement, the hardware does not support it

   - chelsio/chtls: fix always leaking ctrl_skb and another leak caused
     by a race condition

   - fix drivers incorrectly writing into skbs on TX:
      - cadence: force nonlinear buffers to be cloned
      - gianfar: Account for Tx PTP timestamp in the skb headroom
      - gianfar: Replace skb_realloc_headroom with skb_cow_head for PTP

   - can: flexcan:
      - remove FLEXCAN_QUIRK_DISABLE_MECR quirk for LS1021A
      - add ECC initialization for VF610 and LX2160A
      - flexcan_remove(): disable wakeup completely

   - can: fix packet echo functionality:
      - peak_canfd: fix echo management when loopback is on
      - make sure skbs are not freed in IRQ context in case they need to
        be dropped
      - always clone the skbs to make sure they have a reference on the
        socket, and prevent it from disappearing
      - fix real payload length return value for RTR frames

   - can: j1939: return failure on bind if netdev is down, rather than
     waiting indefinitely

  Misc:

   - IPv6: reply ICMP error if the first fragment don't include all
     headers to improve compliance with RFC 8200"

* tag 'net-5.10-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (66 commits)
  ionic: check port ptr before use
  r8169: work around short packet hw bug on RTL8125
  net: openvswitch: silence suspicious RCU usage warning
  chelsio/chtls: fix always leaking ctrl_skb
  chelsio/chtls: fix memory leaks caused by a race
  can: flexcan: flexcan_remove(): disable wakeup completely
  can: flexcan: add ECC initialization for VF610
  can: flexcan: add ECC initialization for LX2160A
  can: flexcan: remove FLEXCAN_QUIRK_DISABLE_MECR quirk for LS1021A
  can: mcp251xfd: remove unneeded break
  can: mcp251xfd: mcp251xfd_regmap_nocrc_read(): fix semicolon.cocci warnings
  can: mcp251xfd: mcp251xfd_regmap_crc_read(): increase severity of CRC read error messages
  can: peak_canfd: pucan_handle_can_rx(): fix echo management when loopback is on
  can: peak_usb: peak_usb_get_ts_time(): fix timestamp wrapping
  can: peak_usb: add range checking in decode operations
  can: xilinx_can: handle failure cases of pm_runtime_get_sync
  can: ti_hecc: ti_hecc_probe(): add missed clk_disable_unprepare() in error path
  can: isotp: padlen(): make const array static, makes object smaller
  can: isotp: isotp_rcv_cf(): enable RX timeout handling in listen-only mode
  can: isotp: Explain PDU in CAN_ISOTP help text
  ...
2020-11-06 11:50:28 -08:00
Ido Schimmel
21584e6a92 selftests: netdevsim: Add test for nexthop offload API
Test various aspects of the nexthop offload API on top of the netdevsim
implementation. Both good and bad flows are tested.

Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2020-11-06 11:28:50 -08:00
KP Singh
4170bc6baa bpf: Exercise syscall operations for inode and sk storage
Use the check_syscall_operations added for task_local_storage to
exercise syscall operations for other local storage maps:

* Check the absence of an element for the given fd.
* Create a new element, retrieve and compare its value.
* Delete the element and check again for absence.

Signed-off-by: KP Singh <kpsingh@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Link: https://lore.kernel.org/bpf/20201106103747.2780972-10-kpsingh@chromium.org
2020-11-06 08:08:38 -08:00
KP Singh
9cde3beead bpf: Add tests for task_local_storage
The test exercises the syscall based map operations by creating a pidfd
for the current process.

For verifying kernel / LSM functionality, the test implements a simple
MAC policy which denies an executable from unlinking itself. The LSM
program bprm_committed_creds sets a task_local_storage with a pointer to
the inode. This is then used to detect if the task is trying to unlink
itself in the inode_unlink LSM hook.

The test copies /bin/rm to /tmp and executes it in a child thread with
the intention of deleting itself. A successful test should prevent the
the running executable from deleting itself.

The bpf programs are also updated to call bpf_spin_{lock, unlock} to
trigger the verfier checks for spin locks.

The temporary file is cleaned up later in the test.

Signed-off-by: KP Singh <kpsingh@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Link: https://lore.kernel.org/bpf/20201106103747.2780972-9-kpsingh@chromium.org
2020-11-06 08:08:38 -08:00
KP Singh
a367efa71b bpf: Update selftests for local_storage to use vmlinux.h
With the fixing of BTF pruning of embedded types being fixed, the test
can be simplified to use vmlinux.h

Signed-off-by: KP Singh <kpsingh@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Song Liu <songliubraving@fb.com>
Link: https://lore.kernel.org/bpf/20201106103747.2780972-8-kpsingh@chromium.org
2020-11-06 08:08:37 -08:00
KP Singh
f0e5ba0bc4 bpf: Fix tests for local_storage
The {inode,sk}_storage_result checking if the correct value was retrieved
was being clobbered unconditionally by the return value of the
bpf_{inode,sk}_storage_delete call.

Also, consistently use the newly added BPF_LOCAL_STORAGE_GET_F_CREATE
flag.

Fixes: cd324d7abb ("bpf: Add selftests for local_storage")
Signed-off-by: KP Singh <kpsingh@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Song Liu <songliubraving@fb.com>
Link: https://lore.kernel.org/bpf/20201106103747.2780972-7-kpsingh@chromium.org
2020-11-06 08:08:37 -08:00
KP Singh
3ca1032ab7 bpf: Implement get_current_task_btf and RET_PTR_TO_BTF_ID
The currently available bpf_get_current_task returns an unsigned integer
which can be used along with BPF_CORE_READ to read data from
the task_struct but still cannot be used as an input argument to a
helper that accepts an ARG_PTR_TO_BTF_ID of type task_struct.

In order to implement this helper a new return type, RET_PTR_TO_BTF_ID,
is added. This is similar to RET_PTR_TO_BTF_ID_OR_NULL but does not
require checking the nullness of returned pointer.

Signed-off-by: KP Singh <kpsingh@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Song Liu <songliubraving@fb.com>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Link: https://lore.kernel.org/bpf/20201106103747.2780972-6-kpsingh@chromium.org
2020-11-06 08:08:37 -08:00
KP Singh
864ab0616d bpftool: Add support for task local storage
Updates the binary to handle the BPF_MAP_TYPE_TASK_STORAGE as
"task_storage" for printing and parsing. Also updates the documentation
and bash completion

Signed-off-by: KP Singh <kpsingh@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Song Liu <songliubraving@fb.com>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Link: https://lore.kernel.org/bpf/20201106103747.2780972-5-kpsingh@chromium.org
2020-11-06 08:08:37 -08:00
KP Singh
8885274d22 libbpf: Add support for task local storage
Updates the bpf_probe_map_type API to also support
BPF_MAP_TYPE_TASK_STORAGE similar to other local storage maps.

Signed-off-by: KP Singh <kpsingh@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Link: https://lore.kernel.org/bpf/20201106103747.2780972-4-kpsingh@chromium.org
2020-11-06 08:08:37 -08:00
KP Singh
4cf1bc1f10 bpf: Implement task local storage
Similar to bpf_local_storage for sockets and inodes add local storage
for task_struct.

The life-cycle of storage is managed with the life-cycle of the
task_struct.  i.e. the storage is destroyed along with the owning task
with a callback to the bpf_task_storage_free from the task_free LSM
hook.

The BPF LSM allocates an __rcu pointer to the bpf_local_storage in
the security blob which are now stackable and can co-exist with other
LSMs.

The userspace map operations can be done by using a pid fd as a key
passed to the lookup, update and delete operations.

Signed-off-by: KP Singh <kpsingh@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Song Liu <songliubraving@fb.com>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Link: https://lore.kernel.org/bpf/20201106103747.2780972-3-kpsingh@chromium.org
2020-11-06 08:08:37 -08:00
Florian Lehner
c6bde958a6 bpf: Lift hashtab key_size limit
Currently key_size of hashtab is limited to MAX_BPF_STACK.
As the key of hashtab can also be a value from a per cpu map it can be
larger than MAX_BPF_STACK.

The use-case for this patch originates to implement allow/disallow
lists for files and file paths. The maximum length of file paths is
defined by PATH_MAX with 4096 chars including nul.
This limit exceeds MAX_BPF_STACK.

Changelog:

v5:
 - Fix cast overflow

v4:
 - Utilize BPF skeleton in tests
 - Rebase

v3:
 - Rebase

v2:
 - Add a test for bpf side

Signed-off-by: Florian Lehner <dev@der-flo.net>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20201029201442.596690-1-dev@der-flo.net
2020-11-05 20:04:46 -08:00
David Verbeiren
d3bec0138b bpf: Zero-fill re-used per-cpu map element
Zero-fill element values for all other cpus than current, just as
when not using prealloc. This is the only way the bpf program can
ensure known initial values for all cpus ('onallcpus' cannot be
set when coming from the bpf program).

The scenario is: bpf program inserts some elements in a per-cpu
map, then deletes some (or userspace does). When later adding
new elements using bpf_map_update_elem(), the bpf program can
only set the value of the new elements for the current cpu.
When prealloc is enabled, previously deleted elements are re-used.
Without the fix, values for other cpus remain whatever they were
when the re-used entry was previously freed.

A selftest is added to validate correct operation in above
scenario as well as in case of LRU per-cpu map element re-use.

Fixes: 6c90598174 ("bpf: pre-allocate hash map elements")
Signed-off-by: David Verbeiren <david.verbeiren@tessares.net>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20201104112332.15191-1-david.verbeiren@tessares.net
2020-11-05 19:55:57 -08:00
Andrii Nakryiko
75fa177769 tools/bpftool: Add bpftool support for split BTF
Add ability to work with split BTF by providing extra -B flag, which allows to
specify the path to the base BTF file.

Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Song Liu <songliubraving@fb.com>
Link: https://lore.kernel.org/bpf/20201105043402.2530976-12-andrii@kernel.org
2020-11-05 18:37:31 -08:00
Andrii Nakryiko
232338fa2f selftests/bpf: Add split BTF dedup selftests
Add selftests validating BTF deduplication for split BTF case. Add a helper
macro that allows to validate entire BTF with raw BTF dump, not just
type-by-type. This saves tons of code and complexity.

Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Song Liu <songliubraving@fb.com>
Link: https://lore.kernel.org/bpf/20201105043402.2530976-11-andrii@kernel.org
2020-11-05 18:37:31 -08:00
Andrii Nakryiko
6b6e6b1d09 libbpf: Accomodate DWARF/compiler bug with duplicated identical arrays
In some cases compiler seems to generate distinct DWARF types for identical
arrays within the same CU. That seems like a bug, but it's already out there
and breaks type graph equivalence checks, so accommodate it anyway by checking
for identical arrays, regardless of their type ID.

Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Song Liu <songliubraving@fb.com>
Link: https://lore.kernel.org/bpf/20201105043402.2530976-10-andrii@kernel.org
2020-11-05 18:37:30 -08:00
Andrii Nakryiko
f86524efcf libbpf: Support BTF dedup of split BTFs
Add support for deduplication split BTFs. When deduplicating split BTF, base
BTF is considered to be immutable and can't be modified or adjusted. 99% of
BTF deduplication logic is left intact (module some type numbering adjustments).
There are only two differences.

First, each type in base BTF gets hashed (expect VAR and DATASEC, of course,
those are always considered to be self-canonical instances) and added into
a table of canonical table candidates. Hashing is a shallow, fast operation,
so mostly eliminates the overhead of having entire base BTF to be a part of
BTF dedup.

Second difference is very critical and subtle. While deduplicating split BTF
types, it is possible to discover that one of immutable base BTF BTF_KIND_FWD
types can and should be resolved to a full STRUCT/UNION type from the split
BTF part.  This is, obviously, can't happen because we can't modify the base
BTF types anymore. So because of that, any type in split BTF that directly or
indirectly references that newly-to-be-resolved FWD type can't be considered
to be equivalent to the corresponding canonical types in base BTF, because
that would result in a loss of type resolution information. So in such case,
split BTF types will be deduplicated separately and will cause some
duplication of type information, which is unavoidable.

With those two changes, the rest of the algorithm manages to deduplicate split
BTF correctly, pointing all the duplicates to their canonical counter-parts in
base BTF, but also is deduplicating whatever unique types are present in split
BTF on their own.

Also, theoretically, split BTF after deduplication could end up with either
empty type section or empty string section. This is handled by libbpf
correctly in one of previous patches in the series.

Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Song Liu <songliubraving@fb.com>
Link: https://lore.kernel.org/bpf/20201105043402.2530976-9-andrii@kernel.org
2020-11-05 18:37:30 -08:00
Andrii Nakryiko
d812362450 libbpf: Fix BTF data layout checks and allow empty BTF
Make data section layout checks stricter, disallowing overlap of types and
strings data.

Additionally, allow BTFs with no type data. There is nothing inherently wrong
with having BTF with no types (put potentially with some strings). This could
be a situation with kernel module BTFs, if module doesn't introduce any new
type information.

Also fix invalid offset alignment check for btf->hdr->type_off.

Fixes: 8a138aed4a ("bpf: btf: Add BTF support to libbpf")
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20201105043402.2530976-8-andrii@kernel.org
2020-11-05 18:37:30 -08:00
Andrii Nakryiko
1306c980cf selftests/bpf: Add checking of raw type dump in BTF writer APIs selftests
Add re-usable btf_helpers.{c,h} to provide BTF-related testing routines. Start
with adding a raw BTF dumping helpers.

Raw BTF dump is the most succinct and at the same time a very human-friendly
way to validate exact contents of BTF types. Cross-validate raw BTF dump and
writable BTF in a single selftest. Raw type dump checks also serve as a good
self-documentation.

Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Song Liu <songliubraving@fb.com>
Link: https://lore.kernel.org/bpf/20201105043402.2530976-7-andrii@kernel.org
2020-11-05 18:37:30 -08:00
Andrii Nakryiko
197389da2f selftests/bpf: Add split BTF basic test
Add selftest validating ability to programmatically generate and then dump
split BTF.

Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Song Liu <songliubraving@fb.com>
Link: https://lore.kernel.org/bpf/20201105043402.2530976-6-andrii@kernel.org
2020-11-05 18:37:30 -08:00
Andrii Nakryiko
ba451366bf libbpf: Implement basic split BTF support
Support split BTF operation, in which one BTF (base BTF) provides basic set of
types and strings, while another one (split BTF) builds on top of base's types
and strings and adds its own new types and strings. From API standpoint, the
fact that the split BTF is built on top of the base BTF is transparent.

Type numeration is transparent. If the base BTF had last type ID #N, then all
types in the split BTF start at type ID N+1. Any type in split BTF can
reference base BTF types, but not vice versa. Programmatically construction of
a split BTF on top of a base BTF is supported: one can create an empty split
BTF with btf__new_empty_split() and pass base BTF as an input, or pass raw
binary data to btf__new_split(), or use btf__parse_xxx_split() variants to get
initial set of split types/strings from the ELF file with .BTF section.

String offsets are similarly transparent and are a logical continuation of
base BTF's strings. When building BTF programmatically and adding a new string
(explicitly with btf__add_str() or implicitly through appending new
types/members), string-to-be-added would first be looked up from the base
BTF's string section and re-used if it's there. If not, it will be looked up
and/or added to the split BTF string section. Similarly to type IDs, types in
split BTF can refer to strings from base BTF absolutely transparently (but not
vice versa, of course, because base BTF doesn't "know" about existence of
split BTF).

Internal type index is slightly adjusted to be zero-indexed, ignoring a fake
[0] VOID type. This allows to handle split/base BTF type lookups transparently
by using btf->start_id type ID offset, which is always 1 for base/non-split
BTF and equals btf__get_nr_types(base_btf) + 1 for the split BTF.

BTF deduplication is not yet supported for split BTF and support for it will
be added in separate patch.

Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Song Liu <songliubraving@fb.com>
Link: https://lore.kernel.org/bpf/20201105043402.2530976-5-andrii@kernel.org
2020-11-05 18:37:30 -08:00
Andrii Nakryiko
88a82c2a9a libbpf: Unify and speed up BTF string deduplication
Revamp BTF dedup's string deduplication to match the approach of writable BTF
string management. This allows to transfer deduplicated strings index back to
BTF object after deduplication without expensive extra memory copying and hash
map re-construction. It also simplifies the code and speeds it up, because
hashmap-based string deduplication is faster than sort + unique approach.

Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Song Liu <songliubraving@fb.com>
Link: https://lore.kernel.org/bpf/20201105043402.2530976-4-andrii@kernel.org
2020-11-05 18:37:30 -08:00
Andrii Nakryiko
d9448f9496 selftest/bpf: Relax btf_dedup test checks
Remove the requirement of a strictly exact string section contents. This used
to be true when string deduplication was done through sorting, but with string
dedup done through hash table, it's no longer true. So relax test harness to
relax strings checks and, consequently, type checks, which now don't have to
have exactly the same string offsets.

Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20201105043402.2530976-3-andrii@kernel.org
2020-11-05 18:37:30 -08:00
Andrii Nakryiko
c81ed6d81e libbpf: Factor out common operations in BTF writing APIs
Factor out commiting of appended type data. Also extract fetching the very
last type in the BTF (to append members to). These two operations are common
across many APIs and will be easier to refactor with split BTF, if they are
extracted into a single place.

Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Song Liu <songliubraving@fb.com>
Link: https://lore.kernel.org/bpf/20201105043402.2530976-2-andrii@kernel.org
2020-11-05 18:37:30 -08:00
Lorenz Bauer
f9b7ff0d7f tools/bpftool: Fix attaching flow dissector
My earlier patch to reject non-zero arguments to flow dissector attach
broke attaching via bpftool. Instead of 0 it uses -1 for target_fd.
Fix this by passing a zero argument when attaching the flow dissector.

Fixes: 1b514239e8 ("bpf: flow_dissector: Check value of unused flags to BPF_PROG_ATTACH")
Reported-by: Jiri Benc <jbenc@redhat.com>
Signed-off-by: Lorenz Bauer <lmb@cloudflare.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Song Liu <songliubraving@fb.com>
Link: https://lore.kernel.org/bpf/20201105115230.296657-1-lmb@cloudflare.com
2020-11-05 18:20:41 -08:00
Linus Torvalds
521b619acd Merge tag 'linux-kselftest-kunit-fixes-5.10-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest
Pull Kunit fixes from Shuah Khan:
 "Several kunit_tool and documentation fixes"

* tag 'linux-kselftest-kunit-fixes-5.10-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest:
  kunit: tools: fix kunit_tool tests for parsing test plans
  Documentation: kunit: Update Kconfig parts for KUNIT's module support
  kunit: test: fix remaining kernel-doc warnings
  kunit: Don't fail test suites if one of them is empty
  kunit: Fix kunit.py --raw_output option
2020-11-05 11:52:17 -08:00
Tommi Rantala
7d764b685e selftests: binderfs: use SKIP instead of XFAIL
XFAIL is gone since commit 9847d24af9 ("selftests/harness: Refactor XFAIL
into SKIP"), use SKIP instead.

Fixes: 9847d24af9 ("selftests/harness: Refactor XFAIL into SKIP")
Signed-off-by: Tommi Rantala <tommi.t.rantala@nokia.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Acked-by: Christian Brauner <christian.brauner@ubuntu.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2020-11-05 10:08:15 -07:00
Tommi Rantala
afba8b0a2c selftests: clone3: use SKIP instead of XFAIL
XFAIL is gone since commit 9847d24af9 ("selftests/harness: Refactor XFAIL
into SKIP"), use SKIP instead.

Fixes: 9847d24af9 ("selftests/harness: Refactor XFAIL into SKIP")
Signed-off-by: Tommi Rantala <tommi.t.rantala@nokia.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Acked-by: Christian Brauner <christian.brauner@ubuntu.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2020-11-05 10:08:15 -07:00
Tommi Rantala
1d44d0dd61 selftests: core: use SKIP instead of XFAIL in close_range_test.c
XFAIL is gone since commit 9847d24af9 ("selftests/harness: Refactor XFAIL
into SKIP"), use SKIP instead.

Fixes: 9847d24af9 ("selftests/harness: Refactor XFAIL into SKIP")
Signed-off-by: Tommi Rantala <tommi.t.rantala@nokia.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Acked-by: Christian Brauner <christian.brauner@ubuntu.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2020-11-05 10:08:15 -07:00