From 6353abd32c8d2a3698115e03b71099858a38591d Mon Sep 17 00:00:00 2001 From: Haoze Xie Date: Mon, 8 Jul 2024 02:01:00 +0800 Subject: [PATCH] perf record: Fix memset out-of-range error Modified the object of 'memset' from '&lost.lost' to '&lost' in record__read_lost_samples. This allows 'memset' to access memory properly without causing out-of-bounds problems. The problems got from builtin-record.c are: In file included from /usr/include/string.h:495, from util/parse-events.h:13, from builtin-record.c:14: In function 'memset', inlined from 'record__read_lost_samples' at builtin-record.c:1958:6, inlined from '__cmd_record.constprop' at builtin-record.c:2817:2: /usr/include/x86_64-linux-gnu/bits/string_fortified.h:71:10: error: '__builtin_memset' offset [17, 64] from the object at 'lost' is out of the bounds of referenced subobject 'lost' with type 'struct perf_record_lost_samples' at offset 0 [-Werror=array-bounds] 71|return __builtin___memset_chk (__dest,__ch,__len,__bos0 (__dest)); | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ The error arised when performing a memset operation on the 'lost' variable, the bytes of 'sizeof(lost)' exceeds that of '&lost.lost', which are 64 and 16. Fixes: 6c1785cd75ef ("perf record: Ensure space for lost samples") Signed-off-by: Haoze Xie Signed-off-by: Yuan Tan Link: https://lore.kernel.org/r/11e12f171b846577cac698cd3999db3d7f6c4d03.1720372317.git.royenheart@gmail.com Signed-off-by: Namhyung Kim --- tools/perf/builtin-record.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/tools/perf/builtin-record.c b/tools/perf/builtin-record.c index 019305b94e5f..a94516e8c522 100644 --- a/tools/perf/builtin-record.c +++ b/tools/perf/builtin-record.c @@ -1955,7 +1955,7 @@ static void record__read_lost_samples(struct record *rec) } if (count.lost) { - memset(&lost.lost, 0, sizeof(lost)); + memset(&lost, 0, sizeof(lost)); lost.lost.header.type = PERF_RECORD_LOST_SAMPLES; __record__save_lost_samples(rec, evsel, &lost.lost, x, y, count.lost, 0); @@ -1965,7 +1965,7 @@ static void record__read_lost_samples(struct record *rec) lost_count = perf_bpf_filter__lost_count(evsel); if (lost_count) { - memset(&lost.lost, 0, sizeof(lost)); + memset(&lost, 0, sizeof(lost)); lost.lost.header.type = PERF_RECORD_LOST_SAMPLES; __record__save_lost_samples(rec, evsel, &lost.lost, 0, 0, lost_count, PERF_RECORD_MISC_LOST_SAMPLES_BPF);