[PATCH 6/8] perf header: Do validation of perf.data HEADER_CPU_DOMAIN_INFO

Arnaldo Carvalho de Melo
2026-04-08T17:29:26Z

As suggested in an unrelated sashiko review:

https://sashiko.dev/#/patchset/20260407195145.2372104-1-acme%40kernel.org

"
Could a malformed perf.data file provide out-of-bounds values for cpu and
domain?
These variables are read directly from the file and used as indices for
cd_map and cd_map[cpu]->domains without any validation against
env->nr_cpus_avail or max_sched_domains.
Similar to the issue above, this is an existing lack of validation that
becomes apparent when looking at the allocation boundaries.
"

Validate it.

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
---
tools/perf/util/header.c | 11 +++++++++++
1 file changed, 11 insertions(+)

diff --git a/tools/perf/util/header.c b/tools/perf/util/header.c
index a18f216f77c27430..4925e33778b91313 100644
--- a/tools/perf/util/header.c
+++ b/tools/perf/util/header.c
@@ -3717,6 +3717,11 @@ static int process_cpu_domain_info(struct feat_fd *ff, void *data __maybe_unused
if (do_read_u32(ff, &cpu))
return -1;

+ if (cpu >= nra) {
+ pr_err("Invalid HEADER_CPU_DOMAIN_INFO: cpu %d >= nr_cpus_avail (%d)\n", cpu, nra);
+ return -1;
+ }
+
cd_map[cpu] = zalloc(sizeof(*cd_map[cpu]));
if (!cd_map[cpu])
return -1;
@@ -3736,6 +3741,12 @@ static int process_cpu_domain_info(struct feat_fd *ff, void *data __maybe_unused
if (do_read_u32(ff, &domain))
return -1;

+ if (domain >= max_sched_domains) {
+ pr_err("Invalid HEADER_CPU_DOMAIN_INFO: domain %d >= max_sched_domains (%d)\n",
+ domain, max_sched_domains);
+ return -1;
+ }
+
d_info = zalloc(sizeof(*d_info));
if (!d_info)
return -1;
--
2.53.0