linux-stable.git/kernel/trace, branch v6.6.66

tracing/eprobe: Fix to release eprobe when failed to add dyn_event

2024-12-14T19:00:20+00:00

[ Upstream commit 494b332064c0ce2f7392fa92632bc50191c1b517 ]

Fix eprobe event to unregister event call and release eprobe when it fails
to add dynamic event correctly.

Link: https://lore.kernel.org/all/173289886698.73724.1959899350183686006.stgit@devnote2/

Fixes: 7491e2c44278 ("tracing: Add a probe that attaches to trace events")
Signed-off-by: Masami Hiramatsu (Google) 
Signed-off-by: Sasha Levin

tracing: Use atomic64_inc_return() in trace_clock_counter()

2024-12-14T19:00:10+00:00

[ Upstream commit eb887c4567d1b0e7684c026fe7df44afa96589e6 ]

Use atomic64_inc_return(&ref) instead of atomic64_add_return(1, &ref)
to use optimized implementation and ease register pressure around
the primitive for targets that implement optimized variant.

Cc: Steven Rostedt 
Cc: Masami Hiramatsu 
Cc: Mathieu Desnoyers 
Link: https://lore.kernel.org/20241007085651.48544-1-ubizjak@gmail.com
Signed-off-by: Uros Bizjak 
Signed-off-by: Steven Rostedt (Google) 
Signed-off-by: Sasha Levin

tracing/ftrace: disable preemption in syscall probe

2024-12-14T19:00:10+00:00

[ Upstream commit 13d750c2c03e9861e15268574ed2c239cca9c9d5 ]

In preparation for allowing system call enter/exit instrumentation to
handle page faults, make sure that ftrace can handle this change by
explicitly disabling preemption within the ftrace system call tracepoint
probes to respect the current expectations within ftrace ring buffer
code.

This change does not yet allow ftrace to take page faults per se within
its probe, but allows its existing probes to adapt to the upcoming
change.

Cc: Michael Jeanson 
Cc: Masami Hiramatsu 
Cc: Peter Zijlstra 
Cc: Alexei Starovoitov 
Cc: Yonghong Song 
Cc: Paul E. McKenney 
Cc: Ingo Molnar 
Cc: Arnaldo Carvalho de Melo 
Cc: Mark Rutland 
Cc: Alexander Shishkin 
Cc: Namhyung Kim 
Cc: Andrii Nakryiko 
Cc: bpf@vger.kernel.org
Cc: Joel Fernandes 
Link: https://lore.kernel.org/20241009010718.2050182-3-mathieu.desnoyers@efficios.com
Acked-by: Masami Hiramatsu (Google) 
Signed-off-by: Mathieu Desnoyers 
Signed-off-by: Steven Rostedt (Google) 
Signed-off-by: Sasha Levin

tracing: Fix cmp_entries_dup() to respect sort() comparison rules

2024-12-14T18:59:52+00:00

commit e63fbd5f6810ed756bbb8a1549c7d4132968baa9 upstream.

The cmp_entries_dup() function used as the comparator for sort()
violated the symmetry and transitivity properties required by the
sorting algorithm. Specifically, it returned 1 whenever memcmp() was
non-zero, which broke the following expectations:

* Symmetry: If x < y, then y > x.
* Transitivity: If x < y and y < z, then x < z.

These violations could lead to incorrect sorting and failure to
correctly identify duplicate elements.

Fix the issue by directly returning the result of memcmp(), which
adheres to the required comparison properties.

Cc: stable@vger.kernel.org
Fixes: 08d43a5fa063 ("tracing: Add lock-free tracing_map")
Link: https://lore.kernel.org/20241203202228.1274403-1-visitorckw@gmail.com
Signed-off-by: Kuan-Wei Chiu 
Signed-off-by: Steven Rostedt (Google) 
Signed-off-by: Greg Kroah-Hartman

ftrace: Fix regression with module command in stack_trace_filter

2024-12-09T09:33:04+00:00

commit 45af52e7d3b8560f21d139b3759735eead8b1653 upstream.

When executing the following command:

    # echo "write*:mod:ext3" > /sys/kernel/tracing/stack_trace_filter

The current mod command causes a null pointer dereference. While commit
0f17976568b3f ("ftrace: Fix regression with module command in stack_trace_filter")
has addressed part of the issue, it left a corner case unhandled, which still
results in a kernel crash.

Cc: stable@vger.kernel.org
Cc: Masami Hiramatsu 
Cc: Mark Rutland 
Cc: Mathieu Desnoyers 
Link: https://lore.kernel.org/20241120052750.275463-1-guoweikang.kernel@gmail.com
Fixes: 04ec7bb642b77 ("tracing: Have the trace_array hold the list of registered func probes");
Signed-off-by: guoweikang 
Signed-off-by: Steven Rostedt (Google) 
Signed-off-by: Greg Kroah-Hartman

trace/trace_event_perf: remove duplicate samples on the first tracepoint event

2024-12-09T09:32:12+00:00

[ Upstream commit afe5960dc208fe069ddaaeb0994d857b24ac19d1 ]

When a tracepoint event is created with attr.freq = 1,
'hwc->period_left' is not initialized correctly. As a result,
in the perf_swevent_overflow() function, when the first time the event occurs,
it calculates the event overflow and the perf_swevent_set_period() returns 3,
this leads to the event are recorded for three duplicate times.

Step to reproduce:
    1. Enable the tracepoint event & starting tracing
         $ echo 1 > /sys/kernel/tracing/events/module/module_free
         $ echo 1 > /sys/kernel/tracing/tracing_on

    2. Record with perf
         $ perf record -a --strict-freq -F 1 -e "module:module_free"

    3. Trigger module_free event.
         $ modprobe -i sunrpc
         $ modprobe -r sunrpc

Result:
     - Trace pipe result:
         $ cat trace_pipe
         modprobe-174509  [003] .....  6504.868896: module_free: sunrpc

     - perf sample:
         modprobe  174509 [003]  6504.868980: module:module_free: sunrpc
         modprobe  174509 [003]  6504.868980: module:module_free: sunrpc
         modprobe  174509 [003]  6504.868980: module:module_free: sunrpc

By setting period_left via perf_swevent_set_period() as other sw_event did,
This problem could be solved.

After patch:
     - Trace pipe result:
         $ cat trace_pipe
         modprobe 1153096 [068] 613468.867774: module:module_free: xfs

     - perf sample
         modprobe 1153096 [068] 613468.867794: module:module_free: xfs

Link: https://lore.kernel.org/20240913021347.595330-1-yeoreum.yun@arm.com
Fixes: bd2b5b12849a ("perf_counter: More aggressive frequency adjustment")
Signed-off-by: Levi Yun 
Acked-by: Namhyung Kim 
Signed-off-by: Steven Rostedt (Google) 
Signed-off-by: Sasha Levin

bpf: Force uprobe bpf program to always return 0

2024-12-09T09:32:11+00:00

[ Upstream commit f505005bc7426f4309880da94cfbfc37efa225bd ]

As suggested by Andrii make uprobe multi bpf programs to always return 0,
so they can't force uprobe removal.

Keeping the int return type for uprobe_prog_run, because it will be used
in following session changes.

Fixes: 89ae89f53d20 ("bpf: Add multi uprobe link")
Suggested-by: Andrii Nakryiko 
Signed-off-by: Jiri Olsa 
Signed-off-by: Andrii Nakryiko 
Acked-by: Andrii Nakryiko 
Link: https://lore.kernel.org/bpf/20241108134544.480660-3-jolsa@kernel.org
Signed-off-by: Sasha Levin

tracing: probes: Fix to zero initialize a local variable

2024-11-01T00:58:34+00:00

commit 0add699ad068d26e5b1da9ff28b15461fc4005df upstream.

Fix to initialize 'val' local variable with zero.
Dan reported that Smatch static code checker reports an error that a local
'val' variable needs to be initialized. Actually, the 'val' is expected to
be initialized by FETCH_OP_ARG in the same loop, but it is not obvious. So
initialize it with zero.

Link: https://lore.kernel.org/all/171092223833.237219.17304490075697026697.stgit@devnote2/

Reported-by: Dan Carpenter 
Closes: https://lore.kernel.org/all/b010488e-68aa-407c-add0-3e059254aaa0@moroto.mountain/
Fixes: 25f00e40ce79 ("tracing/probes: Support $argN in return probe (kprobe and fprobe)")
Reviewed-by: Steven Rostedt (Google) 
Signed-off-by: Masami Hiramatsu (Google) 
Signed-off-by: Greg Kroah-Hartman

bpf,perf: Fix perf_event_detach_bpf_prog error handling

2024-11-01T00:58:30+00:00

[ Upstream commit 0ee288e69d033850bc87abe0f9cc3ada24763d7f ]

Peter reported that perf_event_detach_bpf_prog might skip to release
the bpf program for -ENOENT error from bpf_prog_array_copy.

This can't happen because bpf program is stored in perf event and is
detached and released only when perf event is freed.

Let's drop the -ENOENT check and make sure the bpf program is released
in any case.

Fixes: 170a7e3ea070 ("bpf: bpf_prog_array_copy() should return -ENOENT if exclude_prog not found")
Reported-by: Peter Zijlstra 
Signed-off-by: Jiri Olsa 
Signed-off-by: Andrii Nakryiko 
Link: https://lore.kernel.org/bpf/20241023200352.3488610-1-jolsa@kernel.org

Closes: https://lore.kernel.org/lkml/20241022111638.GC16066@noisy.programming.kicks-ass.net/
Signed-off-by: Sasha Levin

bpf: Add MEM_WRITE attribute

2024-11-01T00:58:30+00:00

[ Upstream commit 6fad274f06f038c29660aa53fbad14241c9fd976 ]

Add a MEM_WRITE attribute for BPF helper functions which can be used in
bpf_func_proto to annotate an argument type in order to let the verifier
know that the helper writes into the memory passed as an argument. In
the past MEM_UNINIT has been (ab)used for this function, but the latter
merely tells the verifier that the passed memory can be uninitialized.

There have been bugs with overloading the latter but aside from that
there are also cases where the passed memory is read + written which
currently cannot be expressed, see also 4b3786a6c539 ("bpf: Zero former
ARG_PTR_TO_{LONG,INT} args in case of error").

Signed-off-by: Daniel Borkmann 
Acked-by: Kumar Kartikeya Dwivedi 
Link: https://lore.kernel.org/r/20241021152809.33343-1-daniel@iogearbox.net
Signed-off-by: Alexei Starovoitov 
Stable-dep-of: 8ea607330a39 ("bpf: Fix overloading of MEM_UNINIT's meaning")
Signed-off-by: Sasha Levin