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 <irogers@google.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Changbin Du <changbin.du@huawei.com>
Cc: Dmitrii Dolgov <9erthalion6@gmail.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: James Clark <james.clark@arm.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung.kim@lge.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rob Herring <robh@kernel.org>
Cc: Sandipan Das <sandipan.das@amd.com>
Cc: Xing Zhengjun <zhengjun.xing@linux.intel.com>
Link: https://lore.kernel.org/r/20230526194442.2355872-3-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

1 files changed, 16 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)
 {