aboutsummaryrefslogtreecommitdiff
path: root/tools/perf/util/symbol.c
diff options
context:
space:
mode:
Diffstat (limited to 'tools/perf/util/symbol.c')
-rw-r--r--tools/perf/util/symbol.c48
1 files changed, 48 insertions, 0 deletions
diff --git a/tools/perf/util/symbol.c b/tools/perf/util/symbol.c
index 516876dfbe5..eec196329fd 100644
--- a/tools/perf/util/symbol.c
+++ b/tools/perf/util/symbol.c
@@ -676,9 +676,30 @@ discard_symbol: rb_erase(&pos->rb_node, root);
return count + moved;
}
+static bool symbol__restricted_filename(const char *filename,
+ const char *restricted_filename)
+{
+ bool restricted = false;
+
+ if (symbol_conf.kptr_restrict) {
+ char *r = realpath(filename, NULL);
+
+ if (r != NULL) {
+ restricted = strcmp(r, restricted_filename) == 0;
+ free(r);
+ return restricted;
+ }
+ }
+
+ return restricted;
+}
+
int dso__load_kallsyms(struct dso *dso, const char *filename,
struct map *map, symbol_filter_t filter)
{
+ if (symbol__restricted_filename(filename, "/proc/kallsyms"))
+ return -1;
+
if (dso__load_all_kallsyms(dso, filename, map) < 0)
return -1;
@@ -1790,6 +1811,9 @@ static int machine__create_modules(struct machine *machine)
modules = path;
}
+ if (symbol__restricted_filename(path, "/proc/modules"))
+ return -1;
+
file = fopen(modules, "r");
if (file == NULL)
return -1;
@@ -2239,6 +2263,9 @@ static u64 machine__get_kernel_start_addr(struct machine *machine)
}
}
+ if (symbol__restricted_filename(filename, "/proc/kallsyms"))
+ return 0;
+
if (kallsyms__parse(filename, &args, symbol__in_kernel) <= 0)
return 0;
@@ -2410,6 +2437,25 @@ static int setup_list(struct strlist **list, const char *list_str,
return 0;
}
+static bool symbol__read_kptr_restrict(void)
+{
+ bool value = false;
+
+ if (geteuid() != 0) {
+ FILE *fp = fopen("/proc/sys/kernel/kptr_restrict", "r");
+ if (fp != NULL) {
+ char line[8];
+
+ if (fgets(line, sizeof(line), fp) != NULL)
+ value = atoi(line) != 0;
+
+ fclose(fp);
+ }
+ }
+
+ return value;
+}
+
int symbol__init(void)
{
const char *symfs;
@@ -2456,6 +2502,8 @@ int symbol__init(void)
if (symfs != symbol_conf.symfs)
free((void *)symfs);
+ symbol_conf.kptr_restrict = symbol__read_kptr_restrict();
+
symbol_conf.initialized = true;
return 0;