linux-stable.git/samples/bpf, branch v5.4.41

samples/bpf: Set -fno-stack-protector when building BPF programs

2020-02-24T07:36:36+00:00

[ Upstream commit 450278977acbf494a20367c22fbb38729772d1fc ]

It seems Clang can in some cases turn on stack protection by default, which
doesn't work with BPF. This was reported once before[0], but it seems the
flag to explicitly turn off the stack protector wasn't added to the
Makefile, so do that now.

The symptom of this is compile errors like the following:

error: :0:0: in function bpf_prog1 i32 (%struct.__sk_buff*): A call to built-in function '__stack_chk_fail' is not supported.

[0] https://www.spinics.net/lists/netdev/msg556400.html

Signed-off-by: Toke Høiland-Jørgensen 
Signed-off-by: Alexei Starovoitov 
Link: https://lore.kernel.org/bpf/20191216103819.359535-1-toke@redhat.com
Signed-off-by: Sasha Levin

samples/bpf: Xdp_redirect_cpu fix missing tracepoint attach

2020-02-11T12:35:29+00:00

commit f9e6bfdbaf0cf304d72c70a05d81acac01a04f48 upstream.

When sample xdp_redirect_cpu was converted to use libbpf, the
tracepoints used by this sample were not getting attached automatically
like with bpf_load.c. The BPF-maps was still getting loaded, thus
nobody notice that the tracepoints were not updating these maps.

This fix doesn't use the new skeleton code, as this bug was introduced
in v5.1 and stable might want to backport this. E.g. Red Hat QA uses
this sample as part of their testing.

Fixes: bbaf6029c49c ("samples/bpf: Convert XDP samples to libbpf usage")
Signed-off-by: Jesper Dangaard Brouer 
Signed-off-by: Alexei Starovoitov 
Acked-by: Andrii Nakryiko 
Link: https://lore.kernel.org/bpf/157685877642.26195.2798780195186786841.stgit@firesoul
Signed-off-by: Greg Kroah-Hartman

samples/bpf: Don't try to remove user's homedir on clean

2020-02-11T12:35:29+00:00

commit b2e5e93ae8af6a34bca536cdc4b453ab1e707b8b upstream.

The 'clean' rule in the samples/bpf Makefile tries to remove backup
files (ending in ~). However, if no such files exist, it will instead try
to remove the user's home directory. While the attempt is mostly harmless,
it does lead to a somewhat scary warning like this:

rm: cannot remove '~': Is a directory

Fix this by using find instead of shell expansion to locate any actual
backup files that need to be removed.

Fixes: b62a796c109c ("samples/bpf: allow make to be run from samples/bpf/ directory")
Signed-off-by: Toke Høiland-Jørgensen 
Signed-off-by: Alexei Starovoitov 
Acked-by: Jesper Dangaard Brouer 
Link: https://lore.kernel.org/bpf/157952560126.1683545.7273054725976032511.stgit@toke.dk
Signed-off-by: Greg Kroah-Hartman

samples/bpf: Fix broken xdp_rxq_info due to map order assumptions

2020-01-26T09:00:58+00:00

commit edbca120a8cdfa5a5793707e33497aa5185875ca upstream.

In the days of using bpf_load.c the order in which the 'maps' sections
were defines in BPF side (*_kern.c) file, were used by userspace side
to identify the map via using the map order as an index. In effect the
order-index is created based on the order the maps sections are stored
in the ELF-object file, by the LLVM compiler.

This have also carried over in libbpf via API bpf_map__next(NULL, obj)
to extract maps in the order libbpf parsed the ELF-object file.

When BTF based maps were introduced a new section type ".maps" were
created. I found that the LLVM compiler doesn't create the ".maps"
sections in the order they are defined in the C-file. The order in the
ELF file is based on the order the map pointer is referenced in the code.

This combination of changes lead to xdp_rxq_info mixing up the map
file-descriptors in userspace, resulting in very broken behaviour, but
without warning the user.

This patch fix issue by instead using bpf_object__find_map_by_name()
to find maps via their names. (Note, this is the ELF name, which can
be longer than the name the kernel retains).

Fixes: be5bca44aa6b ("samples: bpf: convert some XDP samples from bpf_load to libbpf")
Fixes: 451d1dc886b5 ("samples: bpf: update map definition to new syntax BTF-defined map")
Signed-off-by: Jesper Dangaard Brouer 
Signed-off-by: Alexei Starovoitov 
Acked-by: Toke Høiland-Jørgensen 
Acked-by: Andrii Nakryiko 
Link: https://lore.kernel.org/bpf/157529025128.29832.5953245340679936909.stgit@firesoul
Signed-off-by: Greg Kroah-Hartman

samples: bpf: update map definition to new syntax BTF-defined map

2020-01-26T09:00:58+00:00

commit 451d1dc886b548d6e18c933adca326c1307023c9 upstream.

Since, the new syntax of BTF-defined map has been introduced,
the syntax for using maps under samples directory are mixed up.
For example, some are already using the new syntax, and some are using
existing syntax by calling them as 'legacy'.

As stated at commit abd29c931459 ("libbpf: allow specifying map
definitions using BTF"), the BTF-defined map has more compatablility
with extending supported map definition features.

The commit doesn't replace all of the map to new BTF-defined map,
because some of the samples still use bpf_load instead of libbpf, which
can't properly create BTF-defined map.

This will only updates the samples which uses libbpf API for loading bpf
program. (ex. bpf_prog_load_xattr)

Signed-off-by: Daniel T. Lee 
Acked-by: Andrii Nakryiko 
Signed-off-by: Alexei Starovoitov 
Signed-off-by: Greg Kroah-Hartman

samples: bpf: fix syscall_tp due to unused syscall

2020-01-12T11:21:26+00:00

[ Upstream commit fe3300897cbfd76c6cb825776e5ac0ca50a91ca4 ]

Currently, open() is called from the user program and it calls the syscall
'sys_openat', not the 'sys_open'. This leads to an error of the program
of user side, due to the fact that the counter maps are zero since no
function such 'sys_open' is called.

This commit adds the kernel bpf program which are attached to the
tracepoint 'sys_enter_openat' and 'sys_enter_openat'.

Fixes: 1da236b6be963 ("bpf: add a test case for syscalls/sys_{enter|exit}_* tracepoints")
Signed-off-by: Daniel T. Lee 
Signed-off-by: Alexei Starovoitov 
Signed-off-by: Sasha Levin

samples: bpf: Replace symbol compare of trace_event

2020-01-12T11:21:26+00:00

[ Upstream commit bba1b2a890253528c45aa66cf856f289a215bfbc ]

Previously, when this sample is added, commit 1c47910ef8013
("samples/bpf: add perf_event+bpf example"), a symbol 'sys_read' and
'sys_write' has been used without no prefixes. But currently there are
no exact symbols with these under kallsyms and this leads to failure.

This commit changes exact compare to substring compare to keep compatible
with exact symbol or prefixed symbol.

Fixes: 1c47910ef8013 ("samples/bpf: add perf_event+bpf example")
Signed-off-by: Daniel T. Lee 
Signed-off-by: Alexei Starovoitov 
Link: https://lore.kernel.org/bpf/20191205080114.19766-2-danieltimlee@gmail.com
Signed-off-by: Sasha Levin

samples/bpf: fix build by setting HAVE_ATTR_TEST to zero

2019-10-31T20:39:15+00:00

To remove that test_attr__{enabled/open} are used by perf-sys.h, we
set HAVE_ATTR_TEST to zero.

Signed-off-by: Björn Töpel 
Tested-by: KP Singh 
Acked-by: Song Liu 
Cc: Adrian Hunter 
Cc: Alexei Starovoitov 
Cc: Jiri Olsa 
Cc: Namhyung Kim 
Cc: bpf@vger.kernel.org
Cc: netdev@vger.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo 
Signed-off-by: Daniel Borkmann 
Link: http://lore.kernel.org/bpf/20191001113307.27796-3-bjorn.topel@gmail.com

samples/bpf: Add a workaround for asm_inline

2019-10-03T15:37:11+00:00

This was added in commit eb111869301e ("compiler-types.h: add asm_inline
definition") and breaks samples/bpf as clang does not support asm __inline.

Fixes: eb111869301e ("compiler-types.h: add asm_inline definition")
Co-developed-by: Florent Revest 
Signed-off-by: Florent Revest 
Signed-off-by: KP Singh 
Signed-off-by: Daniel Borkmann 
Acked-by: Song Liu 
Acked-by: Andrii Nakryiko 
Link: https://lore.kernel.org/bpf/20191002191652.11432-1-kpsingh@chromium.org

samples/bpf: Fix build for task_fd_query_user.c

2019-10-03T14:27:03+00:00

Add missing include for  which was removed from
perf-sys.h in commit 91854f9a077e ("perf tools: Move everything
related to sys_perf_event_open() to perf-sys.h").

Fixes: 91854f9a077e ("perf tools: Move everything related to sys_perf_event_open() to perf-sys.h")
Reported-by: KP Singh 
Reported-by: Florent Revest 
Signed-off-by: Björn Töpel 
Signed-off-by: Daniel Borkmann 
Tested-by: KP Singh 
Acked-by: Song Liu 
Link: https://lore.kernel.org/bpf/20191001112249.27341-1-bjorn.topel@gmail.com