From 26353a61b977e57b58dd3555bc0422fea46c5ad6 Mon Sep 17 00:00:00 2001 From: Namhyung Kim Date: Mon, 1 Apr 2013 20:35:17 +0900 Subject: [PATCH] perf hists: Fix an invalid memory free on he->branch_info The branch info was allocated for the whole stack and passed matching hist entry for each level during processing samples. Thus when a hist entry tries to free its branch info like in hists__collapse_insert_entry it'll face following error. *** glibc detected *** perf: munmap_chunk(): invalid pointer: 0x00000000014e9d20 *** ======= Backtrace: ========= /lib64/libc.so.6[0x387d47ae16] perf[0x4923bd] perf(cmd_report+0xd68)[0x432a08] perf[0x41a663] perf(main+0x58f)[0x419eaf] /lib64/libc.so.6(__libc_start_main+0xf5)[0x387d421735] perf[0x419f95] Fix it by allocating and copying branch info for each new hist entry. Signed-off-by: Namhyung Kim Cc: Andi Kleen Cc: David Ahern Cc: Ingo Molnar Cc: Jiri Olsa Cc: Paul Mackerras Cc: Peter Zijlstra Cc: Stephane Eranian Link: http://lkml.kernel.org/r/1364816125-12212-2-git-send-email-namhyung@kernel.org Signed-off-by: Arnaldo Carvalho de Melo --- tools/perf/builtin-report.c | 9 ++++++--- tools/perf/util/hist.c | 14 ++++++++++++++ 2 files changed, 20 insertions(+), 3 deletions(-) diff --git a/tools/perf/builtin-report.c b/tools/perf/builtin-report.c index bd0ca81..d9f2de3 100644 --- a/tools/perf/builtin-report.c +++ b/tools/perf/builtin-report.c @@ -187,6 +187,9 @@ static int perf_report__add_branch_hist_entry(struct perf_tool *tool, for (i = 0; i < sample->branch_stack->nr; i++) { if (rep->hide_unresolved && !(bi[i].from.sym && bi[i].to.sym)) continue; + + err = -ENOMEM; + /* * The report shows the percentage of total branches captured * and not events sampled. Thus we use a pseudo period of 1. @@ -195,7 +198,6 @@ static int perf_report__add_branch_hist_entry(struct perf_tool *tool, &bi[i], 1, 1); if (he) { struct annotation *notes; - err = -ENOMEM; bx = he->branch_info; if (bx->from.sym && use_browser == 1 && sort__has_sym) { notes = symbol__annotation(bx->from.sym); @@ -226,11 +228,12 @@ static int perf_report__add_branch_hist_entry(struct perf_tool *tool, } evsel->hists.stats.total_period += 1; hists__inc_nr_events(&evsel->hists, PERF_RECORD_SAMPLE); - err = 0; } else - return -ENOMEM; + goto out; } + err = 0; out: + free(bi); return err; } diff --git a/tools/perf/util/hist.c b/tools/perf/util/hist.c index 6b32721..9438d57 100644 --- a/tools/perf/util/hist.c +++ b/tools/perf/util/hist.c @@ -292,6 +292,20 @@ static struct hist_entry *hist_entry__new(struct hist_entry *template) he->ms.map->referenced = true; if (he->branch_info) { + /* + * This branch info is (a part of) allocated from + * machine__resolve_bstack() and will be freed after + * adding new entries. So we need to save a copy. + */ + he->branch_info = malloc(sizeof(*he->branch_info)); + if (he->branch_info == NULL) { + free(he); + return NULL; + } + + memcpy(he->branch_info, template->branch_info, + sizeof(*he->branch_info)); + if (he->branch_info->from.map) he->branch_info->from.map->referenced = true; if (he->branch_info->to.map) -- 2.7.4