summaryrefslogtreecommitdiff
path: root/tools/perf/util/hist.h
diff options
context:
space:
mode:
authorJiri Olsa <jolsa@redhat.com>2018-02-16 15:36:19 +0300
committerArnaldo Carvalho de Melo <acme@redhat.com>2018-02-16 20:55:47 +0300
commite3ebaa465136ecfedf9c6f4671df02bf625f8125 (patch)
tree082b010d645d001a8e71a0e77e9f3439f4a1c7f3 /tools/perf/util/hist.h
parentb40982e8468b46b8f7f5bba5a7e541ec04a29d7d (diff)
downloadlinux-e3ebaa465136ecfedf9c6f4671df02bf625f8125.tar.xz
perf report: Fix memory corruption in --branch-history mode --branch-history
Jin Yao reported memory corrupton in perf report with branch info used for stack trace: > Following command lines will cause perf crash. > perf record -j call -g -a <application> > perf report --branch-history > > *** Error in `perf': double free or corruption (!prev): 0x00000000104aa040 *** > ======= Backtrace: ========= > /lib/x86_64-linux-gnu/libc.so.6(+0x77725)[0x7f6b37254725] > /lib/x86_64-linux-gnu/libc.so.6(+0x7ff4a)[0x7f6b3725cf4a] > /lib/x86_64-linux-gnu/libc.so.6(cfree+0x4c)[0x7f6b37260abc] > perf[0x51b914] > perf(hist_entry_iter__add+0x1e5)[0x51f305] > perf[0x43cf01] > perf[0x4fa3bf] > perf[0x4fa923] > perf[0x4fd396] > perf[0x4f9614] > perf(perf_session__process_events+0x89e)[0x4fc38e] > perf(cmd_report+0x15d2)[0x43f202] > perf[0x4a059f] > perf(main+0x631)[0x427b71] > /lib/x86_64-linux-gnu/libc.so.6(__libc_start_main+0xf0)[0x7f6b371fd830] > perf(_start+0x29)[0x427d89] For the cumulative output, we allocate the he_cache array based on the --max-stack option value and populate it with data from 'callchain_cursor'. The --max-stack option value does not ensure now the limit for number of callchain_cursor nodes, so the cumulative iter code will allocate smaller array than it's actually needed and cause above corruption. I think the --max-stack limit does not apply here anyway, because we add callchain data as normal hist entries, while the --max-stack control the limit of single entry callchain depth. Using the callchain_cursor.nr as he_cache array count to fix this. Also removing struct hist_entry_iter::max_stack, because there's no longer any use for it. We need more fixes to ensure that the branch stack code follows properly the logic of --max-stack, which is not the case at the moment. Original-patch-by: Jin Yao <yao.jin@linux.intel.com> Signed-off-by: Jiri Olsa <jolsa@kernel.org> Reported-by: Jin Yao <yao.jin@linux.intel.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Kan Liang <kan.liang@intel.com> Cc: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/20180216123619.GA9945@krava Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Diffstat (limited to 'tools/perf/util/hist.h')
-rw-r--r--tools/perf/util/hist.h1
1 files changed, 0 insertions, 1 deletions
diff --git a/tools/perf/util/hist.h b/tools/perf/util/hist.h
index 02721b579746..e869cad4d89f 100644
--- a/tools/perf/util/hist.h
+++ b/tools/perf/util/hist.h
@@ -107,7 +107,6 @@ struct hist_entry_iter {
int curr;
bool hide_unresolved;
- int max_stack;
struct perf_evsel *evsel;
struct perf_sample *sample;