Re: [PATCH v6 00/10] Improvements to memory usage by parse events

Arnaldo Carvalho de Melo
2019-11-07T22:23:22Z

Em Thu, Nov 07, 2019 at 02:14:18PM -0800, Ian Rogers escreveu:
> The parse events parser leaks memory for certain expressions as well
> as allowing a char* to reference stack, heap or .rodata. This series
> of patches improves the hygeine and adds free-ing operations to
> reclaim memory in the parser in error and non-error situations.
>
> The series of patches was generated with LLVM's address sanitizer and
> libFuzzer:
> https://llvm.org/docs/LibFuzzer.html
> called on the parse_events function with randomly generated input. With
> the patches no leaks or memory corruption issues were present.
>
> The v6 patches address a C90 compilation issue.

Please take a look at what is in my perf/core branch, to see what is
left, if something needs fixing, please send a patch on top of that,

Thanks,

- Arnaldo

> The v5 patches add initial error print to the set, as requested by
> Jiri Olsa. They also fix additional 2 missed frees in the patch
> 'before yyabort-ing free components' and remove a redundant new_str
> variable from the patch 'add parse events handle error' as spotted by
> Stephane Eranian.
>
> The v4 patches address review comments from Jiri Olsa, turning a long
> error message into a single warning, fixing the data type in a list
> iterator and reordering patches.
>
> The v3 patches address review comments from Jiri Olsa improving commit
> messages, handling ENOMEM errors from strdup better, and removing a
> printed warning if an invalid event is passed.
>
> The v2 patches are preferable to an earlier proposed patch:
> perf tools: avoid reading out of scope array
>
> Ian Rogers (10):
> perf tools: add parse events handle error
> perf tools: move ALLOC_LIST into a function
> perf tools: avoid a malloc for array events
> perf tools: splice events onto evlist even on error
> perf tools: ensure config and str in terms are unique
> perf tools: add destructors for parse event terms
> perf tools: before yyabort-ing free components
> perf tools: if pmu configuration fails free terms
> perf tools: add a deep delete for parse event terms
> perf tools: report initial event parsing error
>
> tools/perf/arch/powerpc/util/kvm-stat.c | 9 +-
> tools/perf/builtin-stat.c | 2 +
> tools/perf/builtin-trace.c | 16 +-
> tools/perf/tests/parse-events.c | 3 +-
> tools/perf/util/metricgroup.c | 2 +-
> tools/perf/util/parse-events.c | 239 +++++++++++----
> tools/perf/util/parse-events.h | 7 +
> tools/perf/util/parse-events.y | 390 +++++++++++++++++-------
> tools/perf/util/pmu.c | 32 +-
> 9 files changed, 511 insertions(+), 189 deletions(-)
>
> --
> 2.24.0.432.g9d3f5f5b63-goog

--

- Arnaldo