linux.git/tools/lib, branch v6.6.131

libbpf: Fix -Wdiscarded-qualifiers under C23

2026-04-02T11:07:30+00:00

commit d70f79fef65810faf64dbae1f3a1b5623cdb2345 upstream.

glibc ≥ 2.42 (GCC 15) defaults to -std=gnu23, which promotes
-Wdiscarded-qualifiers to an error.

In C23, strstr() and strchr() return "const char *".

Change variable types to const char * where the pointers are never
modified (res, sym_sfx, next_path).

[ shung-hsi.yu: needed to fix kernel build failure due to libbpf since glibc
  2.43+ (which adds 'const' qualifier to strstr) ]
[ Jonas Rebmann: down to one declaration on 6.6 to resolve build error
  with glibc 2.43 ]

Suggested-by: Florian Weimer 
Suggested-by: Andrii Nakryiko 
Signed-off-by: Mikhail Gavrilov 
Link: https://lore.kernel.org/r/20251206092825.1471385-1-mikhail.v.gavrilov@gmail.com
Signed-off-by: Alexei Starovoitov 
Signed-off-by: Shung-Hsi Yu 
Signed-off-by: Greg Kroah-Hartman 
Signed-off-by: Jonas Rebmann 
Signed-off-by: Greg Kroah-Hartman

libperf build: Always place libperf includes first

2026-03-04T12:20:31+00:00

[ Upstream commit 8c5b40678c63be6b85f1c2dc8c8b89d632faf988 ]

When building tools/perf the CFLAGS can contain a directory for the
installed headers.

As the headers may be being installed while building libperf.a this can
cause headers to be partially installed and found in the include path
while building an object file for libperf.a.

The installed header may reference other installed headers that are
missing given the partial nature of the install and then the build fails
with a missing header file.

Avoid this by ensuring the libperf source headers are always first in
the CFLAGS.

Fixes: 3143504918105156 ("libperf: Make libperf.a part of the perf build")
Signed-off-by: Ian Rogers 
Cc: Adrian Hunter 
Cc: Alexander Shishkin 
Cc: Ingo Molnar 
Cc: James Clark 
Cc: Jiri Olsa 
Cc: Namhyung Kim 
Cc: Peter Zijlstra 
Signed-off-by: Arnaldo Carvalho de Melo 
Signed-off-by: Sasha Levin

libperf: Don't remove -g when EXTRA_CFLAGS are used

2026-03-04T12:20:30+00:00

[ Upstream commit f5b07010c13c77541e8ade167d05bef3b8a63739 ]

When using EXTRA_CFLAGS, for example "EXTRA_CFLAGS=-DREFCNT_CHECKING=1",
this construct stops setting -g which you'd expect would not be affected
by adding extra flags. Additionally, EXTRA_CFLAGS should be the last
thing to be appended so that it can be used to undo any defaults. And no
condition is required, just += appends to any existing CFLAGS and also
appends or doesn't append EXTRA_CFLAGS if they are or aren't set.

It's not clear why DEBUG=1 is required for -g in Perf when in libperf
it's always on, but I don't think we need to change that behavior now
because someone may be depending on it.

Signed-off-by: James Clark 
Reviewed-by: Ian Rogers 
Link: https://lore.kernel.org/r/20250319114009.417865-1-james.clark@linaro.org
Signed-off-by: Namhyung Kim 
Stable-dep-of: 8c5b40678c63 ("libperf build: Always place libperf includes first")
Signed-off-by: Sasha Levin

libsubcmd: Fix null intersection case in exclude_cmds()

2026-03-04T12:20:30+00:00

[ Upstream commit b6ee9b6e206b288921c14c906eebf4b32fe0c0d8 ]

When there is no exclusion occurring from the cmds list - for example -
cmds contains ["read-vdso32"] and excludes contains ["archive"] - the
main loop completes with ci == cj == 0. In the original code the loop
processing the remaining elements in the list was conditional:

    if (ci != cj) { ...}

So we end up in the assertion loop since ci < cmds->cnt and we
incorrectly try to assert the list elements to be NULL and fail with
the following error

   help.c:104: exclude_cmds: Assertion `cmds->names[ci] == NULL' failed.

Fix this by moving the if (ci != cj) check inside of a broader loop.
If ci != cj, left shift the list elements, as before, and then
unconditionally advance the ci and cj indicies which also covers the
ci == cj case.

Fixes: 1fdf938168c4d26f ("perf tools: Fix use-after-free in help_unknown_cmd()")
Reviewed-by: Guilherme Amadio 
Signed-off-by: Sri Jayaramappa 
Tested-by: Guilherme Amadio 
Tested-by: Ian Rogers 
Cc: Joshua Hunt 
Cc: Namhyung Kim 
Cc: Peter Zijlstra 
Link: https://lore.kernel.org/r/20251202213632.2873731-1-sjayaram@akamai.com
Signed-off-by: Arnaldo Carvalho de Melo 
Signed-off-by: Sasha Levin

bpftool: Fix truncated netlink dumps

2026-03-04T12:20:20+00:00

[ Upstream commit 3b39d73cc3379360a33eb583b17f21fe55e1288e ]

Netlink requires that the recv buffer used during dumps is at least
min(PAGE_SIZE, 8k) (see the man page). Otherwise the messages will
get truncated. Make sure bpftool follows this requirement, avoid
missing information on systems with large pages.

Acked-by: Quentin Monnet 
Fixes: 7084566a236f ("tools/bpftool: Remove libbpf_internal.h usage in bpftool")
Signed-off-by: Jakub Kicinski 
Link: https://lore.kernel.org/r/20260217194150.734701-1-kuba@kernel.org
Signed-off-by: Alexei Starovoitov 
Signed-off-by: Sasha Levin

libbpf: Fix OOB read in btf_dump_get_bitfield_value

2026-03-04T12:19:30+00:00

[ Upstream commit 5714ca8cba5ed736f3733663c446cbee63a10a64 ]

When dumping bitfield data, btf_dump_get_bitfield_value() reads data
based on the underlying type's size (t->size). However, it does not
verify that the provided data buffer (data_sz) is large enough to
contain these bytes.

If btf_dump__dump_type_data() is called with a buffer smaller than
the type's size, this leads to an out-of-bounds read. This was
confirmed by AddressSanitizer in the linked issue.

Fix this by ensuring we do not read past the provided data_sz limit.

Fixes: a1d3cc3c5eca ("libbpf: Avoid use of __int128 in typed dump display")
Reported-by: Harrison Green 
Suggested-by: Alan Maguire 
Signed-off-by: Varun R Mallya 
Signed-off-by: Andrii Nakryiko 
Link: https://lore.kernel.org/bpf/20260106233527.163487-1-varunrmallya@gmail.com

Closes: https://github.com/libbpf/libbpf/issues/928
Signed-off-by: Sasha Levin

libperf cpumap: Fix perf_cpu_map__max for an empty/NULL map

2026-01-11T14:21:53+00:00

[ Upstream commit a0a4173631bfcfd3520192c0a61cf911d6a52c3a ]

Passing an empty map to perf_cpu_map__max triggered a SEGV. Explicitly
test for the empty map.

Reported-by: Ingo Molnar 
Closes: https://lore.kernel.org/linux-perf-users/aSwt7yzFjVJCEmVp@gmail.com/
Tested-by: Ingo Molnar 
Signed-off-by: Ian Rogers 
Tested-by: Thomas Richter 
Signed-off-by: Namhyung Kim 
Signed-off-by: Sasha Levin

tools: lib: thermal: use pkg-config to locate libnl3

2025-11-24T09:29:49+00:00

[ Upstream commit b31f7f725cd932e2c2b41f3e4b66273653953687 ]

To make libthermal more cross compile friendly use pkg-config to locate
libnl3. Only if that fails fall back to hardcoded /usr/include/libnl3.

Signed-off-by: Sascha Hauer 
Acked-by: Daniel Lezcano 
Signed-off-by: Rafael J. Wysocki 
Signed-off-by: Sasha Levin

tools: lib: thermal: don't preserve owner in install

2025-11-24T09:29:49+00:00

[ Upstream commit 1375152bb02ab2a8435e87ea27034482dbc95f57 ]

Instead of preserving mode, timestamp, and owner, for the object files
during installation, just preserve the mode and timestamp.

When installing as root, the installed files should be owned by root.
When installing as user, --preserve=ownership doesn't work anyway. This
makes --preserve=ownership rather pointless.

Signed-off-by: Emil Dahl Juhl 
Signed-off-by: Sascha Hauer 
Acked-by: Daniel Lezcano 
Signed-off-by: Rafael J. Wysocki 
Signed-off-by: Sasha Levin

libbpf: Fix powerpc's stack register definition in bpf_tracing.h

2025-11-24T09:29:14+00:00

[ Upstream commit 7221b9caf84b3294688228a19273d74ea19a2ee4 ]

retsnoop's build on powerpc (ppc64le) architecture ([0]) failed due to
wrong definition of PT_REGS_SP() macro. Looking at powerpc's
implementation of stack unwinding in perf_callchain_user_64() clearly
shows that stack pointer register is gpr[1].

Fix libbpf's definition of __PT_SP_REG for powerpc to fix all this.

  [0] https://kojipkgs.fedoraproject.org/work/tasks/1544/137921544/build.log

Fixes: 138d6153a139 ("samples/bpf: Enable powerpc support")
Signed-off-by: Andrii Nakryiko 
Reviewed-by: Naveen N Rao (AMD) 
Link: https://lore.kernel.org/r/20251020203643.989467-1-andrii@kernel.org
Signed-off-by: Alexei Starovoitov 
Signed-off-by: Sasha Levin