From 7d4df089d77306914426a604c890175f91a9a459 Mon Sep 17 00:00:00 2001 From: Milian Wolff Date: Wed, 24 May 2017 15:21:23 +0900 Subject: [PATCH] perf report: Don't crash on invalid maps in `-g srcline` mode I just hit a segfault when doing `perf report -g srcline`. Valgrind pointed me at this code as the culprit: ==8359== Invalid read of size 8 ==8359== at 0x3096D9: map__rip_2objdump (map.c:430) ==8359== by 0x2FC1A3: match_chain_srcline (callchain.c:645) ==8359== by 0x2FC1A3: match_chain (callchain.c:700) ==8359== by 0x2FC1A3: append_chain (callchain.c:895) ==8359== by 0x2FC1A3: append_chain_children (callchain.c:846) ==8359== by 0x2FF719: callchain_append (callchain.c:944) ==8359== by 0x2FF719: hist_entry__append_callchain (callchain.c:1058) ==8359== by 0x32FA06: iter_add_single_cumulative_entry (hist.c:908) ==8359== by 0x33195C: hist_entry_iter__add (hist.c:1050) ==8359== by 0x258F65: process_sample_event (builtin-report.c:204) ==8359== by 0x30D60C: perf_session__deliver_event (session.c:1310) ==8359== by 0x30D60C: ordered_events__deliver_event (session.c:119) ==8359== by 0x310D12: __ordered_events__flush (ordered-events.c:210) ==8359== by 0x310D12: ordered_events__flush.part.3 (ordered-events.c:277) ==8359== by 0x30DD3C: perf_session__process_user_event (session.c:1349) ==8359== by 0x30DD3C: perf_session__process_event (session.c:1475) ==8359== by 0x30FC3C: __perf_session__process_events (session.c:1867) ==8359== by 0x30FC3C: perf_session__process_events (session.c:1921) ==8359== by 0x25A985: __cmd_report (builtin-report.c:575) ==8359== by 0x25A985: cmd_report (builtin-report.c:1054) ==8359== by 0x2B9A80: run_builtin (perf.c:296) ==8359== Address 0x70 is not stack'd, malloc'd or (recently) free'd This patch fixes the issue. Signed-off-by: Milian Wolff [ Remove dependency from another change ] Signed-off-by: Namhyung Kim Cc: Arnaldo Carvalho de Melo Cc: Arnaldo Carvalho de Melo Cc: David Ahern Cc: Jiri Olsa Cc: Jiri Olsa Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: Yao Jin Cc: kernel-team@lge.com Link: http://lkml.kernel.org/r/20170524062129.32529-2-namhyung@kernel.org Signed-off-by: Ingo Molnar --- tools/perf/util/callchain.c | 17 +++++++++++------ 1 file changed, 11 insertions(+), 6 deletions(-) diff --git a/tools/perf/util/callchain.c b/tools/perf/util/callchain.c index 81fc29ac798f..b4204b43ed58 100644 --- a/tools/perf/util/callchain.c +++ b/tools/perf/util/callchain.c @@ -621,15 +621,20 @@ enum match_result { static enum match_result match_chain_srcline(struct callchain_cursor_node *node, struct callchain_list *cnode) { - char *left = get_srcline(cnode->ms.map->dso, - map__rip_2objdump(cnode->ms.map, cnode->ip), - cnode->ms.sym, true, false); - char *right = get_srcline(node->map->dso, - map__rip_2objdump(node->map, node->ip), - node->sym, true, false); + char *left = NULL; + char *right = NULL; enum match_result ret = MATCH_EQ; int cmp; + if (cnode->ms.map) + left = get_srcline(cnode->ms.map->dso, + map__rip_2objdump(cnode->ms.map, cnode->ip), + cnode->ms.sym, true, false); + if (node->map) + right = get_srcline(node->map->dso, + map__rip_2objdump(node->map, node->ip), + node->sym, true, false); + if (left && right) cmp = strcmp(left, right); else if (!left && right)