perf evsel: Don't let for_each_group() treat the head of the list as one of its nodes

Address/memory sanitizer was reporting issues in evsel__group_pmu_name
because the for_each_group_evsel loop didn't terminate when the head
was reached, the head would then be cast and accessed as an evsel
leading to invalid memory accesses.

Fix for_each_group_member and for_each_group_evsel to terminate at the
list head. Note, evsel__group_pmu_name no longer iterates the group, but
the problem is present regardless.

Fixes: 717e263fc354d53d ("perf report: Show group description when event group is enabled")
Signed-off-by: Ian Rogers <[email protected]>
Cc: Adrian Hunter <[email protected]>
Cc: Alexander Shishkin <[email protected]>
Cc: Changbin Du <[email protected]>
Cc: Dmitrii Dolgov <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: James Clark <[email protected]>
Cc: Jiri Olsa <[email protected]>
Cc: Kan Liang <[email protected]>
Cc: Mark Rutland <[email protected]>
Cc: Namhyung Kim <[email protected]>
Cc: Namhyung Kim <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Rob Herring <[email protected]>
Cc: Sandipan Das <[email protected]>
Cc: Xing Zhengjun <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>

2 files changed, 17 insertions, 8 deletions

diff --git a/tools/perf/util/evsel.h b/tools/perf/util/evsel.h
index 6d9536ecbc7b..5e8371613565 100644
--- a/tools/perf/util/evsel.h
+++ b/tools/perf/util/evsel.h
@@ -459,16 +459,24 @@ static inline int evsel__group_idx(struct evsel *evsel)
 }
 
 /* Iterates group WITHOUT the leader. */
-#define for_each_group_member(_evsel, _leader) 					\
-for ((_evsel) = list_entry((_leader)->core.node.next, struct evsel, core.node); \
-     (_evsel) && (_evsel)->core.leader == (&_leader->core);					\
-     (_evsel) = list_entry((_evsel)->core.node.next, struct evsel, core.node))
+#define for_each_group_member_head(_evsel, _leader, _head)				\
+for ((_evsel) = list_entry((_leader)->core.node.next, struct evsel, core.node);		\
+	(_evsel) && &(_evsel)->core.node != (_head) &&					\
+	(_evsel)->core.leader == &(_leader)->core;					\
+	(_evsel) = list_entry((_evsel)->core.node.next, struct evsel, core.node))
+
+#define for_each_group_member(_evsel, _leader)				\
+	for_each_group_member_head(_evsel, _leader, &(_leader)->evlist->core.entries)
 
 /* Iterates group WITH the leader. */
-#define for_each_group_evsel(_evsel, _leader) 					\
-for ((_evsel) = _leader; 							\
-     (_evsel) && (_evsel)->core.leader == (&_leader->core);					\
-     (_evsel) = list_entry((_evsel)->core.node.next, struct evsel, core.node))
+#define for_each_group_evsel_head(_evsel, _leader, _head)				\
+for ((_evsel) = _leader;								\
+	(_evsel) && &(_evsel)->core.node != (_head) &&					\
+	(_evsel)->core.leader == &(_leader)->core;					\
+	(_evsel) = list_entry((_evsel)->core.node.next, struct evsel, core.node))
+
+#define for_each_group_evsel(_evsel, _leader)				\
+	for_each_group_evsel_head(_evsel, _leader, &(_leader)->evlist->core.entries)
 
 static inline bool evsel__has_branch_callstack(const struct evsel *evsel)
 {
diff --git a/tools/perf/util/evsel_fprintf.c b/tools/perf/util/evsel_fprintf.c
index 79e42d66f55b..a1655fd7ed9b 100644
--- a/tools/perf/util/evsel_fprintf.c
+++ b/tools/perf/util/evsel_fprintf.c
@@ -2,6 +2,7 @@
 #include <inttypes.h>
 #include <stdio.h>
 #include <stdbool.h>
+#include "util/evlist.h"
 #include "evsel.h"
 #include "util/evsel_fprintf.h"
 #include "util/event.h"