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1216089 commits

Author SHA1 Message Date
Andrii Nakryiko
cbcb199b7c Merge branch 'libbpf/selftests syscall wrapper fixes for RISC-V'
Björn Töpel says:

====================
From: Björn Töpel <bjorn@rivosinc.com>

Commit 08d0ce30e0 ("riscv: Implement syscall wrappers") introduced
some regressions in libbpf, and the kselftests BPF suite, which are
fixed with these three patches.

Note that there's an outstanding fix [1] for ftrace syscall tracing
which is also a fallout from the commit above.

Björn

[1] https://lore.kernel.org/linux-riscv/20231003182407.32198-1-alexghiti@rivosinc.com/

Alexandre Ghiti (1):
  libbpf: Fix syscall access arguments on riscv
====================

Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
2023-10-04 13:19:47 -07:00
Björn Töpel
b55b775f03 selftests/bpf: Define SYS_NANOSLEEP_KPROBE_NAME for riscv
Add missing sys_nanosleep name for RISC-V, which is used by some tests
(e.g. attach_probe).

Fixes: 08d0ce30e0 ("riscv: Implement syscall wrappers")
Signed-off-by: Björn Töpel <bjorn@rivosinc.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Reviewed-by: Sami Tolvanen <samitolvanen@google.com>
Link: https://lore.kernel.org/bpf/20231004110905.49024-4-bjorn@kernel.org
2023-10-04 13:19:44 -07:00
Björn Töpel
0f2692ee43 selftests/bpf: Define SYS_PREFIX for riscv
SYS_PREFIX was missing for a RISC-V, which made a couple of kprobe
tests fail.

Add missing SYS_PREFIX for RISC-V.

Fixes: 08d0ce30e0 ("riscv: Implement syscall wrappers")
Signed-off-by: Björn Töpel <bjorn@rivosinc.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Reviewed-by: Sami Tolvanen <samitolvanen@google.com>
Link: https://lore.kernel.org/bpf/20231004110905.49024-3-bjorn@kernel.org
2023-10-04 13:19:39 -07:00
Alexandre Ghiti
8a412c5c1c libbpf: Fix syscall access arguments on riscv
Since commit 08d0ce30e0 ("riscv: Implement syscall wrappers"), riscv
selects ARCH_HAS_SYSCALL_WRAPPER so let's use the generic implementation
of PT_REGS_SYSCALL_REGS().

Fixes: 08d0ce30e0 ("riscv: Implement syscall wrappers")
Signed-off-by: Alexandre Ghiti <alexghiti@rivosinc.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Reviewed-by: Sami Tolvanen <samitolvanen@google.com>
Link: https://lore.kernel.org/bpf/20231004110905.49024-2-bjorn@kernel.org
2023-10-04 13:19:13 -07:00
Daniel Borkmann
93fb2776f4 Merge branch 'bpf-xsk-sh-umem'
Tushar Vyavahare says:

====================
Implement a test for the SHARED_UMEM feature in this patch set and make
necessary changes/improvements. Ensure that the framework now supports
different streams for different sockets.

v2->v3:
- Set the sock_num at the end of the while loop.
- Declare xsk at the top of the while loop.

v1->v2:
- Remove generate_mac_addresses() and generate mac addresses based on
  the number of sockets in __test_spec_init() function. [Magnus]
- Update Makefile to include find_bit.c for compiling xskxceiver.
- Add bitmap_full() function to verify all bits are set to break the
  while loop in the receive_pkts() and send_pkts() functions.
- Replace __test_and_set_bit() function with __set_bit() function.
- Add single return check for wait_for_tx_completion() function call.

Patch series summary:

1: Move the packet stream from the ifobject struct to the xsk_socket_info
   struct to enable the use of different streams for different sockets
   This will facilitate the sending and receiving of data from multiple
   sockets simultaneously using the SHARED_XDP_UMEM feature.

   It gives flexibility of send/recive individual traffic on particular
   socket.

2: Rename the header file to a generic name so that it can be used by all
   future XDP programs.

3: Move the src_mac and dst_mac fields from the ifobject structure to the
   xsk_socket_info structure to achieve per-socket MAC address assignment.
   Require this in order to steer traffic to various sockets in subsequent
   patches.

4: Improve the receive_pkt() function to enable it to receive packets from
   multiple sockets. Define a sock_num variable to iterate through all the
   sockets in the Rx path. Add nb_valid_entries to check that all the
   expected number of packets are received.

5: The pkt_set() function no longer needs the umem parameter. This commit
   removes the umem parameter from the pkt_set() function.

6: Iterate over all the sockets in the send pkts function. Update
   send_pkts() to handle multiple sockets for sending packets. Multiple TX
   sockets are utilized alternately based on the batch size for improve
   packet transmission.

7: Modify xsk_update_xskmap() to accept the index as an argument, enabling
   the addition of multiple sockets to xskmap.

8: Add a new test for testing shared umem feature. This is accomplished by
   adding a new XDP program and using the multiple sockets. The new XDP
   program redirects the packets based on the destination MAC address.
====================

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2023-10-04 15:26:18 +02:00
Tushar Vyavahare
6d198a89c0 selftests/xsk: Add a test for shared umem feature
Add a new test for testing shared umem feature. This is accomplished by
adding a new XDP program and using the multiple sockets.

The new XDP program redirects the packets based on the destination MAC
address.

Signed-off-by: Tushar Vyavahare <tushar.vyavahare@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Magnus Karlsson <magnus.karlsson@intel.com>
Link: https://lore.kernel.org/bpf/20230927135241.2287547-9-tushar.vyavahare@intel.com
2023-10-04 15:26:02 +02:00
Tushar Vyavahare
fc2cb86495 selftests/xsk: Modify xsk_update_xskmap() to accept the index as an argument
Modify xsk_update_xskmap() to accept the index as an argument, enabling
the addition of multiple sockets to xskmap.

Signed-off-by: Tushar Vyavahare <tushar.vyavahare@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Magnus Karlsson <magnus.karlsson@intel.com>
Link: https://lore.kernel.org/bpf/20230927135241.2287547-8-tushar.vyavahare@intel.com
2023-10-04 15:26:02 +02:00
Tushar Vyavahare
fd0815ae9b selftests/xsk: Iterate over all the sockets in the send pkts function
Update send_pkts() to handle multiple sockets for sending packets.
Multiple TX sockets are utilized alternately based on the batch size for
improve packet transmission.

Signed-off-by: Tushar Vyavahare <tushar.vyavahare@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Magnus Karlsson <magnus.karlsson@intel.com>
Link: https://lore.kernel.org/bpf/20230927135241.2287547-7-tushar.vyavahare@intel.com
2023-10-04 15:26:02 +02:00
Tushar Vyavahare
46e43786cc selftests/xsk: Remove unnecessary parameter from pkt_set() function call
The pkt_set() function no longer needs the umem parameter. This commit
removes the umem parameter from the pkt_set() function.

Signed-off-by: Tushar Vyavahare <tushar.vyavahare@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Magnus Karlsson <magnus.karlsson@intel.com>
Link: https://lore.kernel.org/bpf/20230927135241.2287547-6-tushar.vyavahare@intel.com
2023-10-04 15:26:02 +02:00
Tushar Vyavahare
8913e653e9 selftests/xsk: Iterate over all the sockets in the receive pkts function
Improve the receive_pkt() function to enable it to receive packets from
multiple sockets. Define a sock_num variable to iterate through all the
sockets in the Rx path. Add nb_valid_entries to check that all the
expected number of packets are received.

Revise the function __receive_pkts() to only inspect the receive ring
once, handle any received packets, and promptly return. Implement a bitmap
to store the value of number of sockets. Update Makefile to include
find_bit.c for compiling xskxceiver.

Signed-off-by: Tushar Vyavahare <tushar.vyavahare@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Magnus Karlsson <magnus.karlsson@intel.com>
Link: https://lore.kernel.org/bpf/20230927135241.2287547-5-tushar.vyavahare@intel.com
2023-10-04 15:26:02 +02:00
Tushar Vyavahare
985fd2145a selftests/xsk: Move src_mac and dst_mac to the xsk_socket_info
Move the src_mac and dst_mac fields from the ifobject structure to the
xsk_socket_info structure to achieve per-socket MAC address assignment.

Require this in order to steer traffic to various sockets in subsequent
patches.

Signed-off-by: Tushar Vyavahare <tushar.vyavahare@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Magnus Karlsson <magnus.karlsson@intel.com>
Link: https://lore.kernel.org/bpf/20230927135241.2287547-4-tushar.vyavahare@intel.com
2023-10-04 15:26:01 +02:00
Tushar Vyavahare
93ba112479 selftests/xsk: Rename xsk_xdp_metadata.h to xsk_xdp_common.h
Rename the header file to a generic name so that it can be used by all
future XDP programs. Ensure that the xsk_xdp_common.h header file includes
include guards.

Signed-off-by: Tushar Vyavahare <tushar.vyavahare@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Magnus Karlsson <magnus.karlsson@intel.com>
Link: https://lore.kernel.org/bpf/20230927135241.2287547-3-tushar.vyavahare@intel.com
2023-10-04 15:26:01 +02:00
Tushar Vyavahare
8367eb954e selftests/xsk: Move pkt_stream to the xsk_socket_info
Move the packet stream from the ifobject struct to the xsk_socket_info
struct to enable the use of different streams for different sockets. This
will facilitate the sending and receiving of data from multiple sockets
simultaneously using the SHARED_XDP_UMEM feature.

Signed-off-by: Tushar Vyavahare <tushar.vyavahare@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Magnus Karlsson <magnus.karlsson@intel.com>
Link: https://lore.kernel.org/bpf/20230927135241.2287547-2-tushar.vyavahare@intel.com
2023-10-04 15:26:01 +02:00
Hengqi Chen
2147c8d07e libbpf: Allow Golang symbols in uprobe secdef
Golang symbols in ELF files are different from C/C++
which contains special characters like '*', '(' and ')'.
With generics, things get more complicated, there are
symbols like:

  github.com/cilium/ebpf/internal.(*Deque[go.shape.interface { Format(fmt.State, int32); TypeName() string;github.com/cilium/ebpf/btf.copy() github.com/cilium/ebpf/btf.Type}]).Grow

Matching such symbols using `%m[^\n]` in sscanf, this
excludes newline which typically does not appear in ELF
symbols. This should work in most use-cases and also
work for unicode letters in identifiers. If newline do
show up in ELF symbols, users can still attach to such
symbol by specifying bpf_uprobe_opts::func_name.

A working example can be found at this repo ([0]).

  [0]: https://github.com/chenhengqi/libbpf-go-symbols

Suggested-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Hengqi Chen <hengqi.chen@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20230929155954.92448-1-hengqi.chen@gmail.com
2023-09-29 14:32:20 -07:00
Ruowen Qin
9e09b75079 samples/bpf: Add -fsanitize=bounds to userspace programs
The sanitizer flag, which is supported by both clang and gcc, would make
it easier to debug array index out-of-bounds problems in these programs.

Make the Makfile smarter to detect ubsan support from the compiler and
add the '-fsanitize=bounds' accordingly.

Suggested-by: Mimi Zohar <zohar@linux.ibm.com>
Signed-off-by: Jinghao Jia <jinghao@linux.ibm.com>
Signed-off-by: Jinghao Jia <jinghao7@illinois.edu>
Signed-off-by: Ruowen Qin <ruowenq2@illinois.edu>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Tested-by: Jiri Olsa <jolsa@kernel.org>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Link: https://lore.kernel.org/bpf/20230927045030.224548-2-ruowenq2@illinois.edu
2023-09-28 09:31:05 -07:00
Andrii Nakryiko
0e73ef1d8c Merge branch 'bpf: Add missed stats for kprobes'
Jiri Olsa says:

====================
hi,
at the moment we can't retrieve the number of missed kprobe
executions and subsequent execution of BPF programs.

This patchset adds:
  - counting of missed execution on attach layer for:
    . kprobes attached through perf link (kprobe/ftrace)
    . kprobes attached through kprobe.multi link (fprobe)
  - counting of recursion_misses for BPF kprobe programs

It's still technically possible to create kprobe without perf link (using
SET_BPF perf ioctl) in which case we don't have a way to retrieve the kprobe's
'missed' count. However both libbpf and cilium/ebpf libraries use perf link
if it's available, and for old kernels without perf link support we can use
BPF program to retrieve the kprobe missed count.

v3 changes:
  - added acks [Song]
  - make test_missed not serial [Andrii]

Also available at:
  https://git.kernel.org/pub/scm/linux/kernel/git/jolsa/perf.git
  bpf/missed_stats

thanks,
jirka
====================

Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
2023-09-25 16:37:53 -07:00
Jiri Olsa
85981e0f9e selftests/bpf: Add test for recursion counts of perf event link tracepoint
Adding selftest that puts kprobe on bpf_fentry_test1 that calls bpf_printk
and invokes bpf_trace_printk tracepoint. The bpf_trace_printk tracepoint
has test[234] programs attached to it.

Because kprobe execution goes through bpf_prog_active check, programs
attached to the tracepoint will fail the recursion check and increment the
recursion_misses stats.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Tested-by: Song Liu <song@kernel.org>
Reviewed-by: Song Liu <song@kernel.org>
Link: https://lore.kernel.org/bpf/20230920213145.1941596-10-jolsa@kernel.org
2023-09-25 16:37:45 -07:00
Jiri Olsa
59e83c0187 selftests/bpf: Add test for recursion counts of perf event link kprobe
Adding selftest that puts kprobe.multi on bpf_fentry_test1 that
calls bpf_kfunc_common_test kfunc which has 3 perf event kprobes
and 1 kprobe.multi attached.

Because fprobe (kprobe.multi attach layear) does not have strict
recursion check the kprobe's bpf_prog_active check is hit for test2-5.

Disabling this test for arm64, because there's no fprobe support yet.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Tested-by: Song Liu <song@kernel.org>
Reviewed-by: Song Liu <song@kernel.org>
Acked-by: Hou Tao <houtao1@huawei.com>
Link: https://lore.kernel.org/bpf/20230920213145.1941596-9-jolsa@kernel.org
2023-09-25 16:37:45 -07:00
Jiri Olsa
01e4ae474e selftests/bpf: Add test for missed counts of perf event link kprobe
Adding test that puts kprobe on bpf_fentry_test1 that calls
bpf_kfunc_common_test kfunc, which has also kprobe on.

The latter won't get triggered due to kprobe recursion check
and kprobe missed counter is incremented.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Hou Tao <houtao1@huawei.com>
Link: https://lore.kernel.org/bpf/20230920213145.1941596-8-jolsa@kernel.org
2023-09-25 16:37:44 -07:00
Jiri Olsa
b563b9bae8 bpftool: Display missed count for kprobe perf link
Adding 'missed' field to display missed counts for kprobes
attached by perf event link, like:

  # bpftool link
  5: perf_event  prog 82
          kprobe ffffffff815203e0 ksys_write
  6: perf_event  prog 83
          kprobe ffffffff811d1e50 scheduler_tick  missed 682217

  # bpftool link -jp
  [{
          "id": 5,
          "type": "perf_event",
          "prog_id": 82,
          "retprobe": false,
          "addr": 18446744071584220128,
          "func": "ksys_write",
          "offset": 0,
          "missed": 0
      },{
          "id": 6,
          "type": "perf_event",
          "prog_id": 83,
          "retprobe": false,
          "addr": 18446744071580753488,
          "func": "scheduler_tick",
          "offset": 0,
          "missed": 693469
      }
  ]

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Reviewed-by: Quentin Monnet <quentin@isovalent.com>
Link: https://lore.kernel.org/bpf/20230920213145.1941596-7-jolsa@kernel.org
2023-09-25 16:37:44 -07:00
Jiri Olsa
b24fc35521 bpftool: Display missed count for kprobe_multi link
Adding 'missed' field to display missed counts for kprobes
attached by kprobe multi link, like:

  # bpftool link
  5: kprobe_multi  prog 76
          kprobe.multi  func_cnt 1  missed 1
          addr             func [module]
          ffffffffa039c030 fp3_test [fprobe_test]

  # bpftool link -jp
  [{
          "id": 5,
          "type": "kprobe_multi",
          "prog_id": 76,
          "retprobe": false,
          "func_cnt": 1,
          "missed": 1,
          "funcs": [{
                  "addr": 18446744072102723632,
                  "func": "fp3_test",
                  "module": "fprobe_test"
              }
          ]
      }
  ]

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Reviewed-by: Quentin Monnet <quentin@isovalent.com>
Link: https://lore.kernel.org/bpf/20230920213145.1941596-6-jolsa@kernel.org
2023-09-25 16:37:44 -07:00
Jiri Olsa
dd8657894c bpf: Count missed stats in trace_call_bpf
Increase misses stats in case bpf array execution is skipped
because of recursion check in trace_call_bpf.

Adding bpf_prog_inc_misses_counters that increase misses
counts for all bpf programs in bpf_prog_array.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Tested-by: Song Liu <song@kernel.org>
Reviewed-by: Song Liu <song@kernel.org>
Link: https://lore.kernel.org/bpf/20230920213145.1941596-5-jolsa@kernel.org
2023-09-25 16:37:44 -07:00
Jiri Olsa
3acf8ace68 bpf: Add missed value to kprobe perf link info
Add missed value to kprobe attached through perf link info to
hold the stats of missed kprobe handler execution.

The kprobe's missed counter gets incremented when kprobe handler
is not executed due to another kprobe running on the same cpu.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20230920213145.1941596-4-jolsa@kernel.org
2023-09-25 16:37:44 -07:00
Jiri Olsa
e2b2cd592a bpf: Add missed value to kprobe_multi link info
Add missed value to kprobe_multi link info to hold the stats of missed
kprobe_multi probe.

The missed counter gets incremented when fprobe fails the recursion
check or there's no rethook available for return probe. In either
case the attached bpf program is not executed.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Tested-by: Song Liu <song@kernel.org>
Reviewed-by: Song Liu <song@kernel.org>
Acked-by: Hou Tao <houtao1@huawei.com>
Link: https://lore.kernel.org/bpf/20230920213145.1941596-3-jolsa@kernel.org
2023-09-25 16:37:44 -07:00
Jiri Olsa
f915fcb385 bpf: Count stats for kprobe_multi programs
Adding support to gather missed stats for kprobe_multi
programs due to bpf_prog_active protection.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Tested-by: Song Liu <song@kernel.org>
Reviewed-by: Song Liu <song@kernel.org>
Link: https://lore.kernel.org/bpf/20230920213145.1941596-2-jolsa@kernel.org
2023-09-25 16:37:44 -07:00
Andrii Nakryiko
e0fa6523e0 Merge branch 'add libbpf getters for individual ringbuffers'
Martin Kelly says:

====================
This patch series adds a new ring__ API to libbpf exposing getters for
accessing the individual ringbuffers inside a struct ring_buffer. This is
useful for polling individually, getting available data, or similar use
cases. The API looks like this, and was roughly proposed by Andrii Nakryiko
in another thread:

Getting a ring struct:
struct ring *ring_buffer__ring(struct ring_buffer *rb, unsigned int idx);

Using the ring struct:
unsigned long ring__consumer_pos(const struct ring *r);
unsigned long ring__producer_pos(const struct ring *r);
size_t ring__avail_data_size(const struct ring *r);
size_t ring__size(const struct ring *r);
int ring__map_fd(const struct ring *r);
int ring__consume(struct ring *r);

Changes in v2:
- Addressed all feedback from Andrii Nakryiko
====================

Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
2023-09-25 16:22:55 -07:00
Martin Kelly
cb3d7dd2d0 selftests/bpf: Add tests for ring__consume
Add tests for new API ring__consume.

Signed-off-by: Martin Kelly <martin.kelly@crowdstrike.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20230925215045.2375758-15-martin.kelly@crowdstrike.com
2023-09-25 16:22:43 -07:00
Martin Kelly
16058ff28b libbpf: Add ring__consume
Add ring__consume to consume a single ringbuffer, analogous to
ring_buffer__consume.

Signed-off-by: Martin Kelly <martin.kelly@crowdstrike.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20230925215045.2375758-14-martin.kelly@crowdstrike.com
2023-09-25 16:22:43 -07:00
Martin Kelly
6e38ba5291 selftests/bpf: Add tests for ring__map_fd
Add tests for the new API ring__map_fd.

Signed-off-by: Martin Kelly <martin.kelly@crowdstrike.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20230925215045.2375758-13-martin.kelly@crowdstrike.com
2023-09-25 16:22:43 -07:00
Martin Kelly
ae76939037 libbpf: Add ring__map_fd
Add ring__map_fd to get the file descriptor underlying a given
ringbuffer.

Signed-off-by: Martin Kelly <martin.kelly@crowdstrike.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20230925215045.2375758-12-martin.kelly@crowdstrike.com
2023-09-25 16:22:43 -07:00
Martin Kelly
bb32dd2c8f selftests/bpf: Add tests for ring__size
Add tests for the new API ring__size.

Signed-off-by: Martin Kelly <martin.kelly@crowdstrike.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20230925215045.2375758-11-martin.kelly@crowdstrike.com
2023-09-25 16:22:43 -07:00
Martin Kelly
e79abf717f libbpf: Add ring__size
Add ring__size to get the total size of a given ringbuffer.

Signed-off-by: Martin Kelly <martin.kelly@crowdstrike.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20230925215045.2375758-10-martin.kelly@crowdstrike.com
2023-09-25 16:22:43 -07:00
Martin Kelly
f3a01d385f selftests/bpf: Add tests for ring__avail_data_size
Add test for the new API ring__avail_data_size.

Signed-off-by: Martin Kelly <martin.kelly@crowdstrike.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20230925215045.2375758-9-martin.kelly@crowdstrike.com
2023-09-25 16:22:43 -07:00
Martin Kelly
3b34d29726 libbpf: Add ring__avail_data_size
Add ring__avail_data_size for querying the currently available data in
the ringbuffer, similar to the BPF_RB_AVAIL_DATA flag in
bpf_ringbuf_query. This is racy during ongoing operations but is still
useful for overall information on how a ringbuffer is behaving.

Signed-off-by: Martin Kelly <martin.kelly@crowdstrike.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20230925215045.2375758-8-martin.kelly@crowdstrike.com
2023-09-25 16:22:42 -07:00
Martin Kelly
b18db8712e selftests/bpf: Add tests for ring__*_pos
Add tests for the new APIs ring__producer_pos and ring__consumer_pos.

Signed-off-by: Martin Kelly <martin.kelly@crowdstrike.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20230925215045.2375758-7-martin.kelly@crowdstrike.com
2023-09-25 16:22:42 -07:00
Martin Kelly
059a8c0c5a libbpf: Add ring__producer_pos, ring__consumer_pos
Add APIs to get the producer and consumer position for a given
ringbuffer.

Signed-off-by: Martin Kelly <martin.kelly@crowdstrike.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20230925215045.2375758-6-martin.kelly@crowdstrike.com
2023-09-25 16:22:42 -07:00
Martin Kelly
c1ad2e47f9 selftests/bpf: Add tests for ring_buffer__ring
Add tests for the new API ring_buffer__ring.

Signed-off-by: Martin Kelly <martin.kelly@crowdstrike.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20230925215045.2375758-5-martin.kelly@crowdstrike.com
2023-09-25 16:22:42 -07:00
Martin Kelly
1c97f6afd7 libbpf: Add ring_buffer__ring
Add a new function ring_buffer__ring, which exposes struct ring * to the
user, representing a single ringbuffer.

Signed-off-by: Martin Kelly <martin.kelly@crowdstrike.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20230925215045.2375758-4-martin.kelly@crowdstrike.com
2023-09-25 16:22:42 -07:00
Martin Kelly
ef3b82003e libbpf: Switch rings to array of pointers
Switch rb->rings to be an array of pointers instead of a contiguous
block. This allows for each ring pointer to be stable after
ring_buffer__add is called, which allows us to expose struct ring * to
the user without gotchas. Without this change, the realloc in
ring_buffer__add could invalidate a struct ring *, making it unsafe to
give to the user.

Signed-off-by: Martin Kelly <martin.kelly@crowdstrike.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20230925215045.2375758-3-martin.kelly@crowdstrike.com
2023-09-25 16:22:42 -07:00
Martin Kelly
4448f64c54 libbpf: Refactor cleanup in ring_buffer__add
Refactor the cleanup code in ring_buffer__add to use a unified err_out
label. This reduces code duplication, as well as plugging a potential
leak if mmap_sz != (__u64)(size_t)mmap_sz (currently this would miss
unmapping tmp because ringbuf_unmap_ring isn't called).

Signed-off-by: Martin Kelly <martin.kelly@crowdstrike.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20230925215045.2375758-2-martin.kelly@crowdstrike.com
2023-09-25 16:22:42 -07:00
Andrii Nakryiko
831916fb93 Merge branch 'libbpf: Support symbol versioning for uprobe'
Hengqi Chen says:

====================
Dynamic symbols in shared library may have the same name, for example:

    $ nm -D /lib/x86_64-linux-gnu/libc.so.6 | grep rwlock_wrlock
    000000000009b1a0 T __pthread_rwlock_wrlock@GLIBC_2.2.5
    000000000009b1a0 T pthread_rwlock_wrlock@@GLIBC_2.34
    000000000009b1a0 T pthread_rwlock_wrlock@GLIBC_2.2.5

    $ readelf -W --dyn-syms /lib/x86_64-linux-gnu/libc.so.6 | grep rwlock_wrlock
      706: 000000000009b1a0   878 FUNC    GLOBAL DEFAULT   15 __pthread_rwlock_wrlock@GLIBC_2.2.5
      2568: 000000000009b1a0   878 FUNC    GLOBAL DEFAULT   15 pthread_rwlock_wrlock@@GLIBC_2.34
      2571: 000000000009b1a0   878 FUNC    GLOBAL DEFAULT   15 pthread_rwlock_wrlock@GLIBC_2.2.5

There are two pthread_rwlock_wrlock symbols in libc.so .dynsym section.
The one with @@ is the default version, the other is hidden.
Note that the version info is stored in .gnu.version and .gnu.version_d
sections of libc and the two symbols are at the _same_ offset.

Currently, specify `pthread_rwlock_wrlock`, `pthread_rwlock_wrlock@@GLIBC_2.34`
or `pthread_rwlock_wrlock@GLIBC_2.2.5` in bpf_uprobe_opts::func_name won't work.
Because there are two `pthread_rwlock_wrlock` in .dynsym sections without the
version suffix and both are global bind.

We could solve this by introducing symbol versioning ([0]). So that users can
specify func, func@LIB_VERSION or func@@LIB_VERSION to attach a uprobe.

This patchset resolves symbol conflicts and add symbol versioning for uprobe.
  - Patch 1 resolves symbol conflicts at the same offset
  - Patch 2 adds symbol versioning for dynsym
  - Patch 3 adds selftests for the above changes

Changes from v3:
  - Address comments from Andrii

Changes from v2:
  - Add uretprobe selfttest (Alan)
  - Check symbol exact match (Alan)
  - Fix typo (Jiri)

Changes from v1:
  - Address comments from Alan and Jiri
  - Add selftests (Someone reminds me that there is an attempt at [1]
    and part of the selftest code from Andrii is taken from there)

  [0]: https://refspecs.linuxfoundation.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/symversion.html
  [1]: https://lore.kernel.org/lkml/CAEf4BzZTrjjyyOm3ak9JsssPSh6T_ZmGd677a2rt5e5rBLUrpQ@mail.gmail.com/
====================

Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
2023-09-22 14:27:41 -07:00
Hengqi Chen
7089f85a9e selftests/bpf: Add tests for symbol versioning for uprobe
This exercises the newly added dynsym symbol versioning logics.
Now we accept symbols in form of func, func@LIB_VERSION or
func@@LIB_VERSION.

The test rely on liburandom_read.so. For liburandom_read.so, we have:

    $ nm -D liburandom_read.so
                     w __cxa_finalize@GLIBC_2.17
                     w __gmon_start__
                     w _ITM_deregisterTMCloneTable
                     w _ITM_registerTMCloneTable
    0000000000000000 A LIBURANDOM_READ_1.0.0
    0000000000000000 A LIBURANDOM_READ_2.0.0
    000000000000081c T urandlib_api@@LIBURANDOM_READ_2.0.0
    0000000000000814 T urandlib_api@LIBURANDOM_READ_1.0.0
    0000000000000824 T urandlib_api_sameoffset@LIBURANDOM_READ_1.0.0
    0000000000000824 T urandlib_api_sameoffset@@LIBURANDOM_READ_2.0.0
    000000000000082c T urandlib_read_without_sema@@LIBURANDOM_READ_1.0.0
    00000000000007c4 T urandlib_read_with_sema@@LIBURANDOM_READ_1.0.0
    0000000000011018 D urandlib_read_with_sema_semaphore@@LIBURANDOM_READ_1.0.0

For `urandlib_api`, specifying `urandlib_api` will cause a conflict because
there are two symbols named urandlib_api and both are global bind.
For `urandlib_api_sameoffset`, there are also two symbols in the .so, but
both are at the same offset and essentially they refer to the same function
so no conflict.

Signed-off-by: Hengqi Chen <hengqi.chen@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Reviewed-by: Alan Maguire <alan.maguire@oracle.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Link: https://lore.kernel.org/bpf/20230918024813.237475-4-hengqi.chen@gmail.com
2023-09-22 14:27:41 -07:00
Hengqi Chen
bb7fa09399 libbpf: Support symbol versioning for uprobe
In current implementation, we assume that symbol found in .dynsym section
would have a version suffix and use it to compare with symbol user supplied.
According to the spec ([0]), this assumption is incorrect, the version info
of dynamic symbols are stored in .gnu.version and .gnu.version_d sections
of ELF objects. For example:

    $ nm -D /lib/x86_64-linux-gnu/libc.so.6 | grep rwlock_wrlock
    000000000009b1a0 T __pthread_rwlock_wrlock@GLIBC_2.2.5
    000000000009b1a0 T pthread_rwlock_wrlock@@GLIBC_2.34
    000000000009b1a0 T pthread_rwlock_wrlock@GLIBC_2.2.5

    $ readelf -W --dyn-syms /lib/x86_64-linux-gnu/libc.so.6 | grep rwlock_wrlock
      706: 000000000009b1a0   878 FUNC    GLOBAL DEFAULT   15 __pthread_rwlock_wrlock@GLIBC_2.2.5
      2568: 000000000009b1a0   878 FUNC    GLOBAL DEFAULT   15 pthread_rwlock_wrlock@@GLIBC_2.34
      2571: 000000000009b1a0   878 FUNC    GLOBAL DEFAULT   15 pthread_rwlock_wrlock@GLIBC_2.2.5

In this case, specify pthread_rwlock_wrlock@@GLIBC_2.34 or
pthread_rwlock_wrlock@GLIBC_2.2.5 in bpf_uprobe_opts::func_name won't work.
Because the qualified name does NOT match `pthread_rwlock_wrlock` (without
version suffix) in .dynsym sections.

This commit implements the symbol versioning for dynsym and allows user to
specify symbol in the following forms:
  - func
  - func@LIB_VERSION
  - func@@LIB_VERSION

In case of symbol conflicts, error out and users should resolve it by
specifying a qualified name.

  [0]: https://refspecs.linuxfoundation.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/symversion.html

Signed-off-by: Hengqi Chen <hengqi.chen@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Reviewed-by: Alan Maguire <alan.maguire@oracle.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Link: https://lore.kernel.org/bpf/20230918024813.237475-3-hengqi.chen@gmail.com
2023-09-22 14:27:36 -07:00
Hengqi Chen
7257cee652 libbpf: Resolve symbol conflicts at the same offset for uprobe
Dynamic symbols in shared library may have the same name, for example:

    $ nm -D /lib/x86_64-linux-gnu/libc.so.6 | grep rwlock_wrlock
    000000000009b1a0 T __pthread_rwlock_wrlock@GLIBC_2.2.5
    000000000009b1a0 T pthread_rwlock_wrlock@@GLIBC_2.34
    000000000009b1a0 T pthread_rwlock_wrlock@GLIBC_2.2.5

    $ readelf -W --dyn-syms /lib/x86_64-linux-gnu/libc.so.6 | grep rwlock_wrlock
     706: 000000000009b1a0   878 FUNC    GLOBAL DEFAULT   15 __pthread_rwlock_wrlock@GLIBC_2.2.5
    2568: 000000000009b1a0   878 FUNC    GLOBAL DEFAULT   15 pthread_rwlock_wrlock@@GLIBC_2.34
    2571: 000000000009b1a0   878 FUNC    GLOBAL DEFAULT   15 pthread_rwlock_wrlock@GLIBC_2.2.5

Currently, users can't attach a uprobe to pthread_rwlock_wrlock because
there are two symbols named pthread_rwlock_wrlock and both are global
bind. And libbpf considers it as a conflict.

Since both of them are at the same offset we could accept one of them
harmlessly. Note that we already does this in elf_resolve_syms_offsets.

Signed-off-by: Hengqi Chen <hengqi.chen@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Reviewed-by: Alan Maguire <alan.maguire@oracle.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Link: https://lore.kernel.org/bpf/20230918024813.237475-2-hengqi.chen@gmail.com
2023-09-22 14:18:55 -07:00
Tiezhu Yang
ac0691c75a bpf, docs: Add loongarch64 as arch supporting BPF JIT
As BPF JIT support for loongarch64 was added about one year ago
with commit 5dc615520c ("LoongArch: Add BPF JIT support"), it
is appropriate to add loongarch64 as arch supporting BPF JIT in
bpf and sysctl docs as well.

Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn>
Link: https://lore.kernel.org/r/1695111937-19697-1-git-send-email-yangtiezhu@loongson.cn
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
2023-09-21 15:30:09 -07:00
Jinghao Jia
9220c3ef6f samples/bpf: syscall_tp_user: Fix array out-of-bound access
Commit 06744f2469 ("samples/bpf: Add openat2() enter/exit tracepoint
to syscall_tp sample") added two more eBPF programs to support the
openat2() syscall. However, it did not increase the size of the array
that holds the corresponding bpf_links. This leads to an out-of-bound
access on that array in the bpf_object__for_each_program loop and could
corrupt other variables on the stack. On our testing QEMU, it corrupts
the map1_fds array and causes the sample to fail:

  # ./syscall_tp
  prog #0: map ids 4 5
  verify map:4 val: 5
  map_lookup failed: Bad file descriptor

Dynamically allocate the array based on the number of programs reported
by libbpf to prevent similar inconsistencies in the future

Fixes: 06744f2469 ("samples/bpf: Add openat2() enter/exit tracepoint to syscall_tp sample")
Signed-off-by: Jinghao Jia <jinghao@linux.ibm.com>
Signed-off-by: Ruowen Qin <ruowenq2@illinois.edu>
Signed-off-by: Jinghao Jia <jinghao7@illinois.edu>
Link: https://lore.kernel.org/r/20230917214220.637721-4-jinghao7@illinois.edu
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-09-21 14:32:47 -07:00
Jinghao Jia
0ee352fe0d samples/bpf: syscall_tp_user: Rename num_progs into nr_tests
The variable name num_progs causes confusion because that variable
really controls the number of rounds the test should be executed.

Rename num_progs into nr_tests for the sake of clarity.

Signed-off-by: Jinghao Jia <jinghao@linux.ibm.com>
Signed-off-by: Ruowen Qin <ruowenq2@illinois.edu>
Signed-off-by: Jinghao Jia <jinghao7@illinois.edu>
Link: https://lore.kernel.org/r/20230917214220.637721-3-jinghao7@illinois.edu
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-09-21 14:32:47 -07:00
Alexei Starovoitov
cf67d28de3 Merge branch 'implement-cpuv4-support-for-s390x'
Ilya Leoshkevich says:

====================
Implement cpuv4 support for s390x

v1: https://lore.kernel.org/bpf/20230830011128.1415752-1-iii@linux.ibm.com/
v1 -> v2:
- Redo Disable zero-extension for BPF_MEMSX as Puranjay and Alexei
  suggested.
- Drop the bpf_ct_insert_entry() patch, it went in via the bpf tree.
- Rebase, don't apply A-bs because there were fixed conflicts.

Hi,

This series adds the cpuv4 support to the s390x eBPF JIT.
Patches 1-3 are preliminary bugfixes.
Patches 4-8 implement the new instructions.
Patches 9-10 enable the tests.

Best regards,
Ilya
====================

Link: https://lore.kernel.org/r/20230919101336.2223655-1-iii@linux.ibm.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-09-21 14:22:01 -07:00
Ilya Leoshkevich
c29913bbf4 selftests/bpf: Trim DENYLIST.s390x
Enable all selftests, except the 2 that have to do with the userspace
unwinding, and the new exceptions test, in the s390x CI.

Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
Link: https://lore.kernel.org/r/20230919101336.2223655-11-iii@linux.ibm.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-09-21 14:22:00 -07:00
Ilya Leoshkevich
48c432382d selftests/bpf: Enable the cpuv4 tests for s390x
Now that all the cpuv4 support is in place, enable the tests.

Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
Link: https://lore.kernel.org/r/20230919101336.2223655-10-iii@linux.ibm.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-09-21 14:22:00 -07:00