Open access to perf_events monitoring for CAP_SYS_PERFMON privileged processes.
For backward compatibility reasons access to perf_events subsystem remains open
for CAP_SYS_ADMIN privileged processes but CAP_SYS_ADMIN usage for secure
perf_events monitoring is discouraged with respect to CAP_SYS_PERFMON capability.
Signed-off-by: Alexey Budankov <alexey.budankov@xxxxxxxxxxxxxxx>
---
include/linux/perf_event.h | 9 ++++++---
1 file changed, 6 insertions(+), 3 deletions(-)
diff --git a/include/linux/perf_event.h b/include/linux/perf_event.h
index 34c7c6910026..52313d2cc343 100644
--- a/include/linux/perf_event.h
+++ b/include/linux/perf_event.h
@@ -1285,7 +1285,8 @@ static inline int perf_is_paranoid(void)
static inline int perf_allow_kernel(struct perf_event_attr *attr)
{
- if (sysctl_perf_event_paranoid > 1 && !capable(CAP_SYS_ADMIN))
+ if (sysctl_perf_event_paranoid > 1 &&
+ !(capable(CAP_SYS_PERFMON) || capable(CAP_SYS_ADMIN)))
return -EACCES;
return security_perf_event_open(attr, PERF_SECURITY_KERNEL);
@@ -1293,7 +1294,8 @@ static inline int perf_allow_kernel(struct perf_event_attr *attr)
static inline int perf_allow_cpu(struct perf_event_attr *attr)
{
- if (sysctl_perf_event_paranoid > 0 && !capable(CAP_SYS_ADMIN))
+ if (sysctl_perf_event_paranoid > 0 &&
+ !(capable(CAP_SYS_PERFMON) || capable(CAP_SYS_ADMIN)))
return -EACCES;
return security_perf_event_open(attr, PERF_SECURITY_CPU);
@@ -1301,7 +1303,8 @@ static inline int perf_allow_cpu(struct perf_event_attr *attr)
static inline int perf_allow_tracepoint(struct perf_event_attr *attr)
{
- if (sysctl_perf_event_paranoid > -1 && !capable(CAP_SYS_ADMIN))
+ if (sysctl_perf_event_paranoid > -1 &&
+ !(capable(CAP_SYS_PERFMON) || capable(CAP_SYS_ADMIN)))
return -EPERM;
return security_perf_event_open(attr, PERF_SECURITY_TRACEPOINT);
--
2.20.1
