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author | Namhyung Kim <namhyung@kernel.org> | 2023-06-23 02:53:56 +0300 |
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committer | Namhyung Kim <namhyung@kernel.org> | 2023-06-23 08:10:51 +0300 |
commit | 2d7f5540b8696b855adf4121ce4a9bf77938848f (patch) | |
tree | d622e7e5f370aebe4d28d6fb739eadf85c1ce271 /tools/perf/util/scripting-engines/trace-event-python.c | |
parent | 33fe7c08446af6dda0ff08ff4fa9c921e574477f (diff) | |
download | linux-2d7f5540b8696b855adf4121ce4a9bf77938848f.tar.xz |
perf script: Initialize buffer for regs_map()
The buffer is used to save register mapping in a sample. Normally
perf samples don't have any register so the string should be empty.
But it missed to initialize the buffer when the size is 0. And it's
passed to PyUnicode_FromString() with a garbage data.
So it returns NULL due to invalid input (instead of an empty unicode
string object) which causes a segfault like below:
Thread 2.1 "perf" received signal SIGSEGV, Segmentation fault.
[Switching to Thread 0x7ffff7c83780 (LWP 193775)]
0x00007ffff6dbca2e in PyDict_SetItem () from /lib/x86_64-linux-gnu/libpython3.11.so.1.0
(gdb) bt
#0 0x00007ffff6dbca2e in PyDict_SetItem () from /lib/x86_64-linux-gnu/libpython3.11.so.1.0
#1 0x00007ffff6dbf848 in PyDict_SetItemString () from /lib/x86_64-linux-gnu/libpython3.11.so.1.0
#2 0x000055555575824d in pydict_set_item_string_decref (val=0x0, key=0x5555557f96e3 "iregs", dict=0x7ffff5f7f780)
at util/scripting-engines/trace-event-python.c:145
#3 set_regs_in_dict (evsel=0x555555efc370, sample=0x7fffffffb870, dict=0x7ffff5f7f780)
at util/scripting-engines/trace-event-python.c:776
#4 get_perf_sample_dict (sample=sample@entry=0x7fffffffb870, evsel=evsel@entry=0x555555efc370, al=al@entry=0x7fffffffb2e0,
addr_al=addr_al@entry=0x0, callchain=callchain@entry=0x7ffff63ef440) at util/scripting-engines/trace-event-python.c:923
#5 0x0000555555758ec1 in python_process_tracepoint (sample=0x7fffffffb870, evsel=0x555555efc370, al=0x7fffffffb2e0, addr_al=0x0)
at util/scripting-engines/trace-event-python.c:1044
#6 0x00005555555c5db8 in process_sample_event (tool=<optimized out>, event=<optimized out>, sample=<optimized out>,
evsel=0x555555efc370, machine=0x555555ef4d68) at builtin-script.c:2421
#7 0x00005555556b7793 in perf_session__deliver_event (session=0x555555ef4b60, event=0x7ffff62ff7d0, tool=0x7fffffffc150,
file_offset=30672, file_path=0x555555efb8a0 "perf.data") at util/session.c:1639
#8 0x00005555556bc864 in do_flush (show_progress=true, oe=0x555555efb700) at util/ordered-events.c:245
#9 __ordered_events__flush (oe=oe@entry=0x555555efb700, how=how@entry=OE_FLUSH__FINAL, timestamp=timestamp@entry=0)
at util/ordered-events.c:324
#10 0x00005555556bd06e in ordered_events__flush (oe=oe@entry=0x555555efb700, how=how@entry=OE_FLUSH__FINAL)
at util/ordered-events.c:342
#11 0x00005555556b9d63 in __perf_session__process_events (session=0x555555ef4b60) at util/session.c:2465
#12 perf_session__process_events (session=0x555555ef4b60) at util/session.c:2627
#13 0x00005555555cb1d0 in __cmd_script (script=0x7fffffffc150) at builtin-script.c:2839
#14 cmd_script (argc=<optimized out>, argv=<optimized out>) at builtin-script.c:4365
#15 0x0000555555650811 in run_builtin (p=p@entry=0x555555ed8948 <commands+456>, argc=argc@entry=4, argv=argv@entry=0x7fffffffe240)
at perf.c:323
#16 0x0000555555597eb3 in handle_internal_command (argv=0x7fffffffe240, argc=4) at perf.c:377
#17 run_argv (argv=<synthetic pointer>, argcp=<synthetic pointer>) at perf.c:421
#18 main (argc=4, argv=0x7fffffffe240) at perf.c:537
Fixes: 51cfe7a3e87e ("perf python: Avoid 2 leak sanitizer issues")
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Ingo Molnar <mingo@kernel.org>
Acked-by: Ian Rogers <irogers@google.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Diffstat (limited to 'tools/perf/util/scripting-engines/trace-event-python.c')
-rw-r--r-- | tools/perf/util/scripting-engines/trace-event-python.c | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/tools/perf/util/scripting-engines/trace-event-python.c b/tools/perf/util/scripting-engines/trace-event-python.c index 25fcd6630a4d..94312741443a 100644 --- a/tools/perf/util/scripting-engines/trace-event-python.c +++ b/tools/perf/util/scripting-engines/trace-event-python.c @@ -737,11 +737,11 @@ static void regs_map(struct regs_dump *regs, uint64_t mask, const char *arch, ch unsigned int i = 0, r; int printed = 0; + bf[0] = 0; + if (size <= 0) return; - bf[0] = 0; - if (!regs || !regs->regs) return; |