@@ -4,6 +4,7 @@
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
+#include <linux/capability.h>
#include <linux/kernel.h>
#include <linux/mman.h>
#include <linux/time64.h>
@@ -15,8 +16,10 @@
#include <inttypes.h>
#include "annotate.h"
#include "build-id.h"
+#include "cap.h"
#include "util.h"
#include "debug.h"
+#include "event.h"
#include "machine.h"
#include "map.h"
#include "symbol.h"
@@ -889,7 +892,11 @@ bool symbol__restricted_filename(const char *filename,
{
bool restricted = false;
- if (symbol_conf.kptr_restrict) {
+ /* Per kernel/kallsyms.c:
+ * we also restrict when perf_event_paranoid > 1 w/o CAP_SYSLOG
+ */
+ if (symbol_conf.kptr_restrict ||
+ (perf_event_paranoid() > 1 && !perf_cap__capable(CAP_SYSLOG))) {
char *r = realpath(filename, NULL);
if (r != NULL) {
@@ -2100,9 +2107,9 @@ static bool symbol__read_kptr_restrict(void)
char line[8];
if (fgets(line, sizeof(line), fp) != NULL)
- value = ((geteuid() != 0) || (getuid() != 0)) ?
- (atoi(line) != 0) :
- (atoi(line) == 2);
+ value = perf_cap__capable(CAP_SYSLOG) ?
+ (atoi(line) >= 2) :
+ (atoi(line) != 0);
fclose(fp);
}
Kernel is using CAP_SYSLOG capcbility instead of uid==0 and euid==0 when checking kptr_restrict. Make perf do the same. Also, the kernel is a more restrictive than "no restrictions" in case of kptr_restrict==0, so add the same logic to perf. Signed-off-by: Igor Lubashev <ilubashe@akamai.com> --- tools/perf/util/symbol.c | 15 +++++++++++---- 1 file changed, 11 insertions(+), 4 deletions(-)