diff --git a/include/linux/perf_event.h b/include/linux/perf_event.h index d2a15c0c6f8a..513fea882192 100644 --- a/include/linux/perf_event.h +++ b/include/linux/perf_event.h @@ -1612,6 +1612,12 @@ int perf_event_max_stack_handler(struct ctl_table *table, int write, #define PERF_SECURITY_CPU 1 #define PERF_SECURITY_KERNEL 2 #define PERF_SECURITY_TRACEPOINT 3 +#define PERF_SECURITY_MAX 4 + +static inline bool perf_paranoid_any(void) +{ + return sysctl_perf_event_paranoid >= PERF_SECURITY_MAX; +} static inline int perf_is_paranoid(void) { diff --git a/kernel/events/core.c b/kernel/events/core.c index f0f0f71213a1..81490911aeb1 100644 --- a/kernel/events/core.c +++ b/kernel/events/core.c @@ -415,8 +415,13 @@ static struct kmem_cache *perf_event_cache; * 0 - disallow raw tracepoint access for unpriv * 1 - disallow cpu events for unpriv * 2 - disallow kernel profiling for unpriv + * 4 - disallow all unpriv perf event use */ +#ifdef CONFIG_SECURITY_PERF_EVENTS_RESTRICT +int sysctl_perf_event_paranoid __read_mostly = PERF_SECURITY_MAX; +#else int sysctl_perf_event_paranoid __read_mostly = 2; +#endif /* Minimum for 512 kiB + 1 user control page */ int sysctl_perf_event_mlock __read_mostly = 512 + (PAGE_SIZE / 1024); /* 'free' kiB per user */ @@ -12440,6 +12445,9 @@ SYSCALL_DEFINE5(perf_event_open, if (flags & ~PERF_FLAG_ALL) return -EINVAL; + if (perf_paranoid_any() && !capable(CAP_SYS_ADMIN)) + return -EACCES; + err = perf_copy_attr(attr_uptr, &attr); if (err) return err; diff --git a/security/Kconfig b/security/Kconfig index 52c9af08ad35..2a4686048fff 100644 --- a/security/Kconfig +++ b/security/Kconfig @@ -19,6 +19,15 @@ config SECURITY_DMESG_RESTRICT If you are unsure how to answer this question, answer N. +config SECURITY_PERF_EVENTS_RESTRICT + bool "Restrict unprivileged use of performance events" + depends on PERF_EVENTS + help + If you say Y here, the kernel.perf_event_paranoid sysctl + will be set to 3 by default, and no unprivileged use of the + perf_event_open syscall will be permitted unless it is + changed. + config SECURITY bool "Enable different security models" depends on SYSFS