This is a note to let you know that I've just added the patch titled
perf stat: Fix aggr mode initialization
to the 6.6-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
perf-stat-fix-aggr-mode-initialization.patch
and it can be found in the queue-6.6 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 0231c22b9764c4c5e7b581f2412d1ac4d5a5bd7a
Author: Ian Rogers <irogers@xxxxxxxxxx>
Date: Tue Sep 5 17:39:12 2023 -0700
perf stat: Fix aggr mode initialization
[ Upstream commit a84fbf205609313594b86065c67e823f09ebe29b ]
Generating metrics llc_code_read_mpi_demand_plus_prefetch,
llc_data_read_mpi_demand_plus_prefetch,
llc_miss_local_memory_bandwidth_read,
llc_miss_local_memory_bandwidth_write,
nllc_miss_remote_memory_bandwidth_read, memory_bandwidth_read,
memory_bandwidth_write, uncore_frequency, upi_data_transmit_bw,
C2_Pkg_Residency, C3_Core_Residency, C3_Pkg_Residency,
C6_Core_Residency, C6_Pkg_Residency, C7_Core_Residency,
C7_Pkg_Residency, UNCORE_FREQ and tma_info_system_socket_clks would
trigger an address sanitizer heap-buffer-overflows on a SkylakeX.
```
==2567752==ERROR: AddressSanitizer: heap-buffer-overflow on address 0x5020003ed098 at pc 0x5621a816654e bp 0x7fffb55d4da0 sp 0x7fffb55d4d98
READ of size 4 at 0x5020003eee78 thread T0
#0 0x558265d6654d in aggr_cpu_id__is_empty tools/perf/util/cpumap.c:694:12
#1 0x558265c914da in perf_stat__get_aggr tools/perf/builtin-stat.c:1490:6
#2 0x558265c914da in perf_stat__get_global_cached tools/perf/builtin-stat.c:1530:9
#3 0x558265e53290 in should_skip_zero_counter tools/perf/util/stat-display.c:947:31
#4 0x558265e53290 in print_counter_aggrdata tools/perf/util/stat-display.c:985:18
#5 0x558265e51931 in print_counter tools/perf/util/stat-display.c:1110:3
#6 0x558265e51931 in evlist__print_counters tools/perf/util/stat-display.c:1571:5
#7 0x558265c8ec87 in print_counters tools/perf/builtin-stat.c:981:2
#8 0x558265c8cc71 in cmd_stat tools/perf/builtin-stat.c:2837:3
#9 0x558265bb9bd4 in run_builtin tools/perf/perf.c:323:11
#10 0x558265bb98eb in handle_internal_command tools/perf/perf.c:377:8
#11 0x558265bb9389 in run_argv tools/perf/perf.c:421:2
#12 0x558265bb9389 in main tools/perf/perf.c:537:3
```
The issue was the use of testing a cpumap with NULL rather than using
empty, as a map containing the dummy value isn't NULL and the -1
results in an empty aggr map being allocated which legitimately
overflows when any member is accessed.
Fixes: 8a96f454f5668572 ("perf stat: Avoid SEGV if core.cpus isn't set")
Signed-off-by: Ian Rogers <irogers@xxxxxxxxxx>
Acked-by: Namhyung Kim <namhyung@xxxxxxxxxx>
Cc: Adrian Hunter <adrian.hunter@xxxxxxxxx>
Cc: Alexander Shishkin <alexander.shishkin@xxxxxxxxxxxxxxx>
Cc: Ian Rogers <irogers@xxxxxxxxxx>
Cc: Ingo Molnar <mingo@xxxxxxxxxx>
Cc: Jiri Olsa <jolsa@xxxxxxxxxx>
Cc: Mark Rutland <mark.rutland@xxxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Link: https://lore.kernel.org/r/20230906003912.3317462-1-irogers@xxxxxxxxxx
Signed-off-by: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/tools/perf/builtin-stat.c b/tools/perf/builtin-stat.c
index 07b48f6df48eb..a3af805a1d572 100644
--- a/tools/perf/builtin-stat.c
+++ b/tools/perf/builtin-stat.c
@@ -1622,7 +1622,7 @@ static int perf_stat_init_aggr_mode(void)
* taking the highest cpu number to be the size of
* the aggregation translate cpumap.
*/
- if (evsel_list->core.user_requested_cpus)
+ if (!perf_cpu_map__empty(evsel_list->core.user_requested_cpus))
nr = perf_cpu_map__max(evsel_list->core.user_requested_cpus).cpu;
else
nr = 0;
