linux-stable.git/tools/lib, branch v5.10.22

libbpf: Ignore non function pointer member in struct_ops

2021-03-04T10:37:33+00:00

[ Upstream commit d2836dddc95d5dd82c7cb23726c97d8c9147f050 ]

When libbpf initializes the kernel's struct_ops in
"bpf_map__init_kern_struct_ops()", it enforces all
pointer types must be a function pointer and rejects
others.  It turns out to be too strict.  For example,
when directly using "struct tcp_congestion_ops" from vmlinux.h,
it has a "struct module *owner" member and it is set to NULL
in a bpf_tcp_cc.o.

Instead, it only needs to ensure the member is a function
pointer if it has been set (relocated) to a bpf-prog.
This patch moves the "btf_is_func_proto(kern_mtype)" check
after the existing "if (!prog) { continue; }".  The original debug
message in "if (!prog) { continue; }" is also removed since it is
no longer valid.  Beside, there is a later debug message to tell
which function pointer is set.

The "btf_is_func_proto(mtype)" has already been guaranteed
in "bpf_object__collect_st_ops_relos()" which has been run
before "bpf_map__init_kern_struct_ops()".  Thus, this check
is removed.

v2:
- Remove outdated debug message (Andrii)
  Remove because there is a later debug message to tell
  which function pointer is set.
- Following mtype->type is no longer needed. Remove:
  "skip_mods_and_typedefs(btf, mtype->type, &mtype_id)"
- Do "if (!prog)" test before skip_mods_and_typedefs.

Fixes: 590a00888250 ("bpf: libbpf: Add STRUCT_OPS support")
Signed-off-by: Martin KaFai Lau 
Signed-off-by: Andrii Nakryiko 
Acked-by: Andrii Nakryiko 
Link: https://lore.kernel.org/bpf/20210212021030.266932-1-kafai@fb.com
Signed-off-by: Sasha Levin

perf evlist: Fix id index for heterogeneous systems

2021-01-27T10:55:11+00:00

[ Upstream commit fc705fecf3a0c9128933cc6db59159c050aaca33 ]

perf_evlist__set_sid_idx() updates perf_sample_id with the evlist map
index, CPU number and TID. It is passed indexes to the evsel's cpu and
thread maps, but references the evlist's maps instead. That results in
using incorrect CPU numbers on heterogeneous systems. Fix it by using
evsel maps.

The id index (PERF_RECORD_ID_INDEX) is used by AUX area tracing when in
sampling mode. Having an incorrect CPU number causes the trace data to
be attributed to the wrong CPU, and can result in decoder errors because
the trace data is then associated with the wrong process.

Committer notes:

Keep the class prefix convention in the function name, switching from
perf_evlist__set_sid_idx() to perf_evsel__set_sid_idx().

Fixes: 3c659eedada2fbf9 ("perf tools: Add id index")
Signed-off-by: Adrian Hunter 
Cc: Jin Yao 
Cc: Jiri Olsa 
Link: http://lore.kernel.org/lkml/20210121125446.11287-1-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo 
Signed-off-by: Sasha Levin

libperf tests: Fail when failing to get a tracepoint id

2021-01-27T10:55:04+00:00

[ Upstream commit 66dd86b2a2bee129c70f7ff054d3a6a2e5f8eb20 ]

Permissions are necessary to get a tracepoint id. Fail the test when the
read fails.

Signed-off-by: Ian Rogers 
Acked-by: Jiri Olsa 
Cc: Alexander Shishkin 
Cc: Mark Rutland 
Cc: Namhyung Kim 
Cc: Peter Zijlstra 
Cc: Stephane Eranian 
Link: http://lore.kernel.org/lkml/20210114180250.3853825-2-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo 
Signed-off-by: Sasha Levin

libperf tests: If a test fails return non-zero

2021-01-27T10:55:04+00:00

[ Upstream commit bba2ea17ef553aea0df80cb64399fe2f70f225dd ]

If a test fails return -1 rather than 0. This is consistent with the
return value in test-cpumap.c

Signed-off-by: Ian Rogers 
Acked-by: Jiri Olsa 
Cc: Alexander Shishkin 
Cc: Mark Rutland 
Cc: Namhyung Kim 
Cc: Peter Zijlstra 
Cc: Stephane Eranian 
Link: http://lore.kernel.org/lkml/20210114180250.3853825-1-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo 
Signed-off-by: Sasha Levin

libbpf: Sanitise map names before pinning

2020-12-30T10:53:33+00:00

[ Upstream commit 9cf309c56f7910a81fbe053b6f11c3b1f0987b12 ]

When we added sanitising of map names before loading programs to libbpf, we
still allowed periods in the name. While the kernel will accept these for
the map names themselves, they are not allowed in file names when pinning
maps. This means that bpf_object__pin_maps() will fail if called on an
object that contains internal maps (such as sections .rodata).

Fix this by replacing periods with underscores when constructing map pin
paths. This only affects the paths generated by libbpf when
bpf_object__pin_maps() is called with a path argument. Any pin paths set
by bpf_map__set_pin_path() are unaffected, and it will still be up to the
caller to avoid invalid characters in those.

Fixes: 113e6b7e15e2 ("libbpf: Sanitise internal map names so they are not rejected by the kernel")
Signed-off-by: Toke Høiland-Jørgensen 
Signed-off-by: Andrii Nakryiko 
Link: https://lore.kernel.org/bpf/20201203093306.107676-1-toke@redhat.com
Signed-off-by: Sasha Levin

libbpf: Fix ring_buffer__poll() to return number of consumed samples

2020-12-02T04:21:45+00:00

Fix ring_buffer__poll() to return the number of non-discarded records
consumed, just like its documentation states. It's also consistent with
ring_buffer__consume() return. Fix up selftests with wrong expected results.

Fixes: bf99c936f947 ("libbpf: Add BPF ring buffer support")
Fixes: cb1c9ddd5525 ("selftests/bpf: Add BPF ringbuf selftests")
Signed-off-by: Andrii Nakryiko 
Signed-off-by: Alexei Starovoitov 
Link: https://lore.kernel.org/bpf/20201130223336.904192-1-andrii@kernel.org

libbpf: Fix VERSIONED_SYM_COUNT number parsing

2020-11-19T16:45:12+00:00

We remove "other info" from "readelf -s --wide" output when
parsing GLOBAL_SYM_COUNT variable, which was added in [1].
But we don't do that for VERSIONED_SYM_COUNT and it's failing
the check_abi target on powerpc Fedora 33.

The extra "other info" wasn't problem for VERSIONED_SYM_COUNT
parsing until commit [2] added awk in the pipe, which assumes
that the last column is symbol, but it can be "other info".

Adding "other info" removal for VERSIONED_SYM_COUNT the same
way as we did for GLOBAL_SYM_COUNT parsing.

[1] aa915931ac3e ("libbpf: Fix readelf output parsing for Fedora")
[2] 746f534a4809 ("tools/libbpf: Avoid counting local symbols in ABI check")

Fixes: 746f534a4809 ("tools/libbpf: Avoid counting local symbols in ABI check")
Signed-off-by: Jiri Olsa 
Signed-off-by: Alexei Starovoitov 
Acked-by: Andrii Nakryiko 
Link: https://lore.kernel.org/bpf/20201118211350.1493421-1-jolsa@kernel.org

libbpf: Don't attempt to load unused subprog as an entry-point BPF program

2020-11-09T21:15:23+00:00

If BPF code contains unused BPF subprogram and there are no other subprogram
calls (which can realistically happen in real-world applications given
sufficiently smart Clang code optimizations), libbpf will erroneously assume
that subprograms are entry-point programs and will attempt to load them with
UNSPEC program type.

Fix by not relying on subcall instructions and rather detect it based on the
structure of BPF object's sections.

Fixes: 9a94f277c4fb ("tools: libbpf: restore the ability to load programs from .text section")
Reported-by: Dmitrii Banshchikov 
Signed-off-by: Andrii Nakryiko 
Signed-off-by: Daniel Borkmann 
Acked-by: Yonghong Song 
Link: https://lore.kernel.org/bpf/20201107000251.256821-1-andrii@kernel.org

libbpf: Fix possible use after free in xsk_socket__delete

2020-11-04T20:37:29+00:00

Fix a possible use after free in xsk_socket__delete that will happen
if xsk_put_ctx() frees the ctx. To fix, save the umem reference taken
from the context and just use that instead.

Fixes: 2f6324a3937f ("libbpf: Support shared umems between queues and devices")
Signed-off-by: Magnus Karlsson 
Signed-off-by: Daniel Borkmann 
Acked-by: Andrii Nakryiko 
Link: https://lore.kernel.org/bpf/1604396490-12129-3-git-send-email-magnus.karlsson@gmail.com

libbpf: Fix null dereference in xsk_socket__delete

2020-11-04T20:37:28+00:00

Fix a possible null pointer dereference in xsk_socket__delete that
will occur if a null pointer is fed into the function.

Fixes: 2f6324a3937f ("libbpf: Support shared umems between queues and devices")
Reported-by: Andrii Nakryiko 
Signed-off-by: Magnus Karlsson 
Signed-off-by: Daniel Borkmann 
Acked-by: Andrii Nakryiko 
Link: https://lore.kernel.org/bpf/1604396490-12129-2-git-send-email-magnus.karlsson@gmail.com