diff --git a/arch/powerpc/perf/core-book3s.c b/arch/powerpc/perf/core-book3s.c index 4004dbdab9c7..680458064bb5 100644 --- a/arch/powerpc/perf/core-book3s.c +++ b/arch/powerpc/perf/core-book3s.c @@ -95,7 +95,7 @@ static inline unsigned long perf_ip_adjust(struct pt_regs *regs) { return 0; } -static inline void perf_get_data_addr(struct pt_regs *regs, u64 *addrp) { } +static inline void perf_get_data_addr(struct perf_event *event, struct pt_regs *regs, u64 *addrp) { } static inline u32 perf_get_misc_flags(struct pt_regs *regs) { return 0; @@ -126,7 +126,7 @@ static unsigned long ebb_switch_in(bool ebb, struct cpu_hw_events *cpuhw) static inline void power_pmu_bhrb_enable(struct perf_event *event) {} static inline void power_pmu_bhrb_disable(struct perf_event *event) {} static void power_pmu_sched_task(struct perf_event_context *ctx, bool sched_in) {} -static inline void power_pmu_bhrb_read(struct cpu_hw_events *cpuhw) {} +static inline void power_pmu_bhrb_read(struct perf_event *event, struct cpu_hw_events *cpuhw) {} static void pmao_restore_workaround(bool ebb) { } #endif /* CONFIG_PPC32 */ @@ -170,7 +170,7 @@ static inline unsigned long perf_ip_adjust(struct pt_regs *regs) * pointed to by SIAR; this is indicated by the [POWER6_]MMCRA_SDSYNC, the * [POWER7P_]MMCRA_SDAR_VALID bit in MMCRA, or the SDAR_VALID bit in SIER. */ -static inline void perf_get_data_addr(struct pt_regs *regs, u64 *addrp) +static inline void perf_get_data_addr(struct perf_event *event, struct pt_regs *regs, u64 *addrp) { unsigned long mmcra = regs->dsisr; bool sdar_valid; @@ -195,8 +195,7 @@ static inline void perf_get_data_addr(struct pt_regs *regs, u64 *addrp) if (!(mmcra & MMCRA_SAMPLE_ENABLE) || sdar_valid) *addrp = mfspr(SPRN_SDAR); - if (perf_paranoid_kernel() && !capable(CAP_SYS_ADMIN) && - is_kernel_addr(mfspr(SPRN_SDAR))) + if (is_kernel_addr(mfspr(SPRN_SDAR)) && perf_allow_kernel(&event->attr) != 0) *addrp = 0; } @@ -435,7 +434,7 @@ static __u64 power_pmu_bhrb_to(u64 addr) } /* Processing BHRB entries */ -static void power_pmu_bhrb_read(struct cpu_hw_events *cpuhw) +static void power_pmu_bhrb_read(struct perf_event *event, struct cpu_hw_events *cpuhw) { u64 val; u64 addr; @@ -463,8 +462,7 @@ static void power_pmu_bhrb_read(struct cpu_hw_events *cpuhw) * exporting it to userspace (avoid exposure of regions * where we could have speculative execution) */ - if (perf_paranoid_kernel() && !capable(CAP_SYS_ADMIN) && - is_kernel_addr(addr)) + if (is_kernel_addr(addr) && perf_allow_kernel(&event->attr) != 0) continue; /* Branches are read most recent first (ie. mfbhrb 0 is @@ -2068,12 +2066,12 @@ static void record_and_restart(struct perf_event *event, unsigned long val, if (event->attr.sample_type & (PERF_SAMPLE_ADDR | PERF_SAMPLE_PHYS_ADDR)) - perf_get_data_addr(regs, &data.addr); + perf_get_data_addr(event, regs, &data.addr); if (event->attr.sample_type & PERF_SAMPLE_BRANCH_STACK) { struct cpu_hw_events *cpuhw; cpuhw = this_cpu_ptr(&cpu_hw_events); - power_pmu_bhrb_read(cpuhw); + power_pmu_bhrb_read(event, cpuhw); data.br_stack = &cpuhw->bhrb_stack; } diff --git a/arch/x86/events/intel/bts.c b/arch/x86/events/intel/bts.c index 510f9461407e..5a1cd9c3addf 100644 --- a/arch/x86/events/intel/bts.c +++ b/arch/x86/events/intel/bts.c @@ -563,9 +563,11 @@ static int bts_event_init(struct perf_event *event) * Note that the default paranoia setting permits unprivileged * users to profile the kernel. */ - if (event->attr.exclude_kernel && perf_paranoid_kernel() && - !capable(CAP_SYS_ADMIN)) - return -EACCES; + if (event->attr.exclude_kernel) { + ret = perf_allow_kernel(&event->attr); + if (ret) + return ret; + } if (x86_add_exclusive(x86_lbr_exclusive_bts)) return -EBUSY; diff --git a/arch/x86/events/intel/core.c b/arch/x86/events/intel/core.c index 2dd8b0d64295..0fc020856e5c 100644 --- a/arch/x86/events/intel/core.c +++ b/arch/x86/events/intel/core.c @@ -3109,8 +3109,9 @@ static int intel_pmu_hw_config(struct perf_event *event) if (x86_pmu.version < 3) return -EINVAL; - if (perf_paranoid_cpu() && !capable(CAP_SYS_ADMIN)) - return -EACCES; + ret = perf_allow_cpu(&event->attr); + if (ret) + return ret; event->hw.config |= ARCH_PERFMON_EVENTSEL_ANY; diff --git a/arch/x86/events/intel/p4.c b/arch/x86/events/intel/p4.c index d32c0eed38ca..4f9ac72968db 100644 --- a/arch/x86/events/intel/p4.c +++ b/arch/x86/events/intel/p4.c @@ -776,8 +776,9 @@ static int p4_validate_raw_event(struct perf_event *event) * the user needs special permissions to be able to use it */ if (p4_ht_active() && p4_event_bind_map[v].shared) { - if (perf_paranoid_cpu() && !capable(CAP_SYS_ADMIN)) - return -EACCES; + v = perf_allow_cpu(&event->attr); + if (v) + return v; } /* ESCR EventMask bits may be invalid */ diff --git a/include/linux/lsm_hooks.h b/include/linux/lsm_hooks.h index 97a020c616ad..0605f866044a 100644 --- a/include/linux/lsm_hooks.h +++ b/include/linux/lsm_hooks.h @@ -1777,6 +1777,14 @@ union security_list_options { int (*bpf_prog_alloc_security)(struct bpf_prog_aux *aux); void (*bpf_prog_free_security)(struct bpf_prog_aux *aux); #endif /* CONFIG_BPF_SYSCALL */ +#ifdef CONFIG_PERF_EVENTS + int (*perf_event_open)(struct perf_event_attr *attr, int type); + int (*perf_event_alloc)(struct perf_event *event); + void (*perf_event_free)(struct perf_event *event); + int (*perf_event_read)(struct perf_event *event); + int (*perf_event_write)(struct perf_event *event); + +#endif }; struct security_hook_heads { @@ -2011,6 +2019,13 @@ struct security_hook_heads { struct hlist_head bpf_prog_alloc_security; struct hlist_head bpf_prog_free_security; #endif /* CONFIG_BPF_SYSCALL */ +#ifdef CONFIG_PERF_EVENTS + struct hlist_head perf_event_open; + struct hlist_head perf_event_alloc; + struct hlist_head perf_event_free; + struct hlist_head perf_event_read; + struct hlist_head perf_event_write; +#endif } __randomize_layout; /* diff --git a/include/linux/perf_event.h b/include/linux/perf_event.h index 205c79491de3..f40925aaf35e 100644 --- a/include/linux/perf_event.h +++ b/include/linux/perf_event.h @@ -55,6 +55,7 @@ struct perf_guest_info_callbacks { #include #include #include +#include #include struct perf_callchain_entry { @@ -704,6 +705,9 @@ struct perf_event { struct perf_cgroup *cgrp; /* cgroup event is attach to */ #endif +#ifdef CONFIG_SECURITY + void *security; +#endif struct list_head sb_list; #endif /* CONFIG_PERF_EVENTS */ }; @@ -1194,24 +1198,46 @@ extern int perf_cpu_time_max_percent_handler(struct ctl_table *table, int write, int perf_event_max_stack_handler(struct ctl_table *table, int write, void __user *buffer, size_t *lenp, loff_t *ppos); +/* Access to perf_event_open(2) syscall. */ +#define PERF_SECURITY_OPEN 0 + +/* Finer grained perf_event_open(2) access control. */ +#define PERF_SECURITY_CPU 1 +#define PERF_SECURITY_KERNEL 2 +#define PERF_SECURITY_TRACEPOINT 3 + static inline bool perf_paranoid_any(void) { return sysctl_perf_event_paranoid > 2; } -static inline bool perf_paranoid_tracepoint_raw(void) +static inline int perf_is_paranoid(void) { return sysctl_perf_event_paranoid > -1; } -static inline bool perf_paranoid_cpu(void) +static inline int perf_allow_kernel(struct perf_event_attr *attr) { - return sysctl_perf_event_paranoid > 0; + if (sysctl_perf_event_paranoid > 1 && !capable(CAP_SYS_ADMIN)) + return -EACCES; + + return security_perf_event_open(attr, PERF_SECURITY_KERNEL); } -static inline bool perf_paranoid_kernel(void) +static inline int perf_allow_cpu(struct perf_event_attr *attr) { - return sysctl_perf_event_paranoid > 1; + if (sysctl_perf_event_paranoid > 0 && !capable(CAP_SYS_ADMIN)) + return -EACCES; + + return security_perf_event_open(attr, PERF_SECURITY_CPU); +} + +static inline int perf_allow_tracepoint(struct perf_event_attr *attr) +{ + if (sysctl_perf_event_paranoid > -1 && !capable(CAP_SYS_ADMIN)) + return -EPERM; + + return security_perf_event_open(attr, PERF_SECURITY_TRACEPOINT); } extern void perf_event_init(void); diff --git a/include/linux/security.h b/include/linux/security.h index 75f4156c84d7..9fa7661125ab 100644 --- a/include/linux/security.h +++ b/include/linux/security.h @@ -1843,5 +1843,42 @@ static inline void free_secdata(void *secdata) { } #endif /* CONFIG_SECURITY */ -#endif /* ! __LINUX_SECURITY_H */ +#ifdef CONFIG_PERF_EVENTS +struct perf_event_attr; +struct perf_event; +#ifdef CONFIG_SECURITY +extern int security_perf_event_open(struct perf_event_attr *attr, int type); +extern int security_perf_event_alloc(struct perf_event *event); +extern void security_perf_event_free(struct perf_event *event); +extern int security_perf_event_read(struct perf_event *event); +extern int security_perf_event_write(struct perf_event *event); +#else +static inline int security_perf_event_open(struct perf_event_attr *attr, + int type) +{ + return 0; +} + +static inline int security_perf_event_alloc(struct perf_event *event) +{ + return 0; +} + +static inline void security_perf_event_free(struct perf_event *event) +{ +} + +static inline int security_perf_event_read(struct perf_event *event) +{ + return 0; +} + +static inline int security_perf_event_write(struct perf_event *event) +{ + return 0; +} +#endif /* CONFIG_SECURITY */ +#endif /* CONFIG_PERF_EVENTS */ + +#endif /* ! __LINUX_SECURITY_H */ diff --git a/kernel/events/core.c b/kernel/events/core.c index 69e6c77e9daf..fa5048fb7e62 100644 --- a/kernel/events/core.c +++ b/kernel/events/core.c @@ -4126,8 +4126,9 @@ find_get_context(struct pmu *pmu, struct task_struct *task, if (!task) { /* Must be root to operate on a CPU event: */ - if (perf_paranoid_cpu() && !capable(CAP_SYS_ADMIN)) - return ERR_PTR(-EACCES); + err = perf_allow_cpu(&event->attr); + if (err) + return ERR_PTR(err); cpuctx = per_cpu_ptr(pmu->pmu_cpu_context, cpu); ctx = &cpuctx->ctx; @@ -4431,6 +4432,8 @@ static void _free_event(struct perf_event *event) unaccount_event(event); + security_perf_event_free(event); + if (event->rb) { /* * Can happen when we close an event with re-directed output. @@ -4884,6 +4887,10 @@ perf_read(struct file *file, char __user *buf, size_t count, loff_t *ppos) struct perf_event_context *ctx; int ret; + ret = security_perf_event_read(event); + if (ret) + return ret; + ctx = perf_event_ctx_lock(event); ret = __perf_read(event, buf, count); perf_event_ctx_unlock(event, ctx); @@ -5145,6 +5152,11 @@ static long perf_ioctl(struct file *file, unsigned int cmd, unsigned long arg) struct perf_event_context *ctx; long ret; + /* Treat ioctl like writes as it is likely a mutating operation. */ + ret = security_perf_event_write(event); + if (ret) + return ret; + ctx = perf_event_ctx_lock(event); ret = _perf_ioctl(event, cmd, arg); perf_event_ctx_unlock(event, ctx); @@ -5607,6 +5619,10 @@ static int perf_mmap(struct file *file, struct vm_area_struct *vma) if (!(vma->vm_flags & VM_SHARED)) return -EINVAL; + ret = security_perf_event_read(event); + if (ret) + return ret; + vma_size = vma->vm_end - vma->vm_start; if (vma->vm_pgoff == 0) { @@ -5720,7 +5736,7 @@ accounting: lock_limit >>= PAGE_SHIFT; locked = vma->vm_mm->pinned_vm + extra; - if ((locked > lock_limit) && perf_paranoid_tracepoint_raw() && + if ((locked > lock_limit) && perf_is_paranoid() && !capable(CAP_IPC_LOCK)) { ret = -EPERM; goto unlock; @@ -10186,11 +10202,20 @@ perf_event_alloc(struct perf_event_attr *attr, int cpu, } } + err = security_perf_event_alloc(event); + if (err) + goto err_callchain_buffer; + /* symmetric to unaccount_event() in _free_event() */ account_event(event); return event; +err_callchain_buffer: + if (!event->parent) { + if (event->attr.sample_type & PERF_SAMPLE_CALLCHAIN) + put_callchain_buffers(); + } err_addr_filters: kfree(event->addr_filter_ranges); @@ -10308,9 +10333,11 @@ static int perf_copy_attr(struct perf_event_attr __user *uattr, attr->branch_sample_type = mask; } /* privileged levels capture (kernel, hv): check permissions */ - if ((mask & PERF_SAMPLE_BRANCH_PERM_PLM) - && perf_paranoid_kernel() && !capable(CAP_SYS_ADMIN)) - return -EACCES; + if (mask & PERF_SAMPLE_BRANCH_PERM_PLM) { + ret = perf_allow_kernel(attr); + if (ret) + return ret; + } } if (attr->sample_type & PERF_SAMPLE_REGS_USER) { @@ -10526,13 +10553,19 @@ SYSCALL_DEFINE5(perf_event_open, if (perf_paranoid_any() && !capable(CAP_SYS_ADMIN)) return -EACCES; + /* Do we allow access to perf_event_open(2) ? */ + err = security_perf_event_open(&attr, PERF_SECURITY_OPEN); + if (err) + return err; + err = perf_copy_attr(attr_uptr, &attr); if (err) return err; if (!attr.exclude_kernel) { - if (perf_paranoid_kernel() && !capable(CAP_SYS_ADMIN)) - return -EACCES; + err = perf_allow_kernel(&attr); + if (err) + return err; } if (attr.namespaces) { @@ -10549,9 +10582,11 @@ SYSCALL_DEFINE5(perf_event_open, } /* Only privileged users can get physical addresses */ - if ((attr.sample_type & PERF_SAMPLE_PHYS_ADDR) && - perf_paranoid_kernel() && !capable(CAP_SYS_ADMIN)) - return -EACCES; + if ((attr.sample_type & PERF_SAMPLE_PHYS_ADDR)) { + err = perf_allow_kernel(&attr); + if (err) + return err; + } /* * In cgroup mode, the pid argument is used to pass the fd diff --git a/kernel/trace/trace_event_perf.c b/kernel/trace/trace_event_perf.c index f5b3bf0e69f6..fb54fdcd11dc 100644 --- a/kernel/trace/trace_event_perf.c +++ b/kernel/trace/trace_event_perf.c @@ -8,6 +8,7 @@ #include #include +#include #include "trace.h" #include "trace_probe.h" @@ -26,8 +27,10 @@ static int total_ref_count; static int perf_trace_event_perm(struct trace_event_call *tp_event, struct perf_event *p_event) { + int ret; + if (tp_event->perf_perm) { - int ret = tp_event->perf_perm(tp_event, p_event); + ret = tp_event->perf_perm(tp_event, p_event); if (ret) return ret; } @@ -46,8 +49,9 @@ static int perf_trace_event_perm(struct trace_event_call *tp_event, /* The ftrace function trace is allowed only for root. */ if (ftrace_event_is_function(tp_event)) { - if (perf_paranoid_tracepoint_raw() && !capable(CAP_SYS_ADMIN)) - return -EPERM; + ret = perf_allow_tracepoint(&p_event->attr); + if (ret) + return ret; if (!is_sampling_event(p_event)) return 0; @@ -82,8 +86,9 @@ static int perf_trace_event_perm(struct trace_event_call *tp_event, * ...otherwise raw tracepoint data can be a severe data leak, * only allow root to have these. */ - if (perf_paranoid_tracepoint_raw() && !capable(CAP_SYS_ADMIN)) - return -EPERM; + ret = perf_allow_tracepoint(&p_event->attr); + if (ret) + return ret; return 0; } diff --git a/security/security.c b/security/security.c index 74dcf97783bb..1baf58502368 100644 --- a/security/security.c +++ b/security/security.c @@ -1805,3 +1805,30 @@ void security_bpf_prog_free(struct bpf_prog_aux *aux) call_void_hook(bpf_prog_free_security, aux); } #endif /* CONFIG_BPF_SYSCALL */ + +#ifdef CONFIG_PERF_EVENTS +int security_perf_event_open(struct perf_event_attr *attr, int type) +{ + return call_int_hook(perf_event_open, 0, attr, type); +} + +int security_perf_event_alloc(struct perf_event *event) +{ + return call_int_hook(perf_event_alloc, 0, event); +} + +void security_perf_event_free(struct perf_event *event) +{ + call_void_hook(perf_event_free, event); +} + +int security_perf_event_read(struct perf_event *event) +{ + return call_int_hook(perf_event_read, 0, event); +} + +int security_perf_event_write(struct perf_event *event) +{ + return call_int_hook(perf_event_write, 0, event); +} +#endif /* CONFIG_PERF_EVENTS */ diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c index 109ab510bdb1..7624ce702aff 100644 --- a/security/selinux/hooks.c +++ b/security/selinux/hooks.c @@ -6940,6 +6940,68 @@ static void selinux_bpf_prog_free(struct bpf_prog_aux *aux) } #endif + +#ifdef CONFIG_PERF_EVENTS +static int selinux_perf_event_open(struct perf_event_attr *attr, int type) +{ + u32 requested, sid = current_sid(); + + if (type == PERF_SECURITY_OPEN) + requested = PERF_EVENT__OPEN; + else if (type == PERF_SECURITY_CPU) + requested = PERF_EVENT__CPU; + else if (type == PERF_SECURITY_KERNEL) + requested = PERF_EVENT__KERNEL; + else if (type == PERF_SECURITY_TRACEPOINT) + requested = PERF_EVENT__TRACEPOINT; + else + return -EINVAL; + + return avc_has_perm(&selinux_state, sid, sid, SECCLASS_PERF_EVENT, + requested, NULL); +} + +static int selinux_perf_event_alloc(struct perf_event *event) +{ + struct perf_event_security_struct *perfsec; + + perfsec = kzalloc(sizeof(*perfsec), GFP_KERNEL); + if (!perfsec) + return -ENOMEM; + + perfsec->sid = current_sid(); + event->security = perfsec; + + return 0; +} + +static void selinux_perf_event_free(struct perf_event *event) +{ + struct perf_event_security_struct *perfsec = event->security; + + event->security = NULL; + kfree(perfsec); +} + +static int selinux_perf_event_read(struct perf_event *event) +{ + struct perf_event_security_struct *perfsec = event->security; + u32 sid = current_sid(); + + return avc_has_perm(&selinux_state, sid, perfsec->sid, + SECCLASS_PERF_EVENT, PERF_EVENT__READ, NULL); +} + +static int selinux_perf_event_write(struct perf_event *event) +{ + struct perf_event_security_struct *perfsec = event->security; + u32 sid = current_sid(); + + return avc_has_perm(&selinux_state, sid, perfsec->sid, + SECCLASS_PERF_EVENT, PERF_EVENT__WRITE, NULL); +} +#endif + static struct security_hook_list selinux_hooks[] __lsm_ro_after_init = { LSM_HOOK_INIT(binder_set_context_mgr, selinux_binder_set_context_mgr), LSM_HOOK_INIT(binder_transaction, selinux_binder_transaction), @@ -7175,6 +7237,14 @@ static struct security_hook_list selinux_hooks[] __lsm_ro_after_init = { LSM_HOOK_INIT(bpf_map_free_security, selinux_bpf_map_free), LSM_HOOK_INIT(bpf_prog_free_security, selinux_bpf_prog_free), #endif + +#ifdef CONFIG_PERF_EVENTS + LSM_HOOK_INIT(perf_event_open, selinux_perf_event_open), + LSM_HOOK_INIT(perf_event_alloc, selinux_perf_event_alloc), + LSM_HOOK_INIT(perf_event_free, selinux_perf_event_free), + LSM_HOOK_INIT(perf_event_read, selinux_perf_event_read), + LSM_HOOK_INIT(perf_event_write, selinux_perf_event_write), +#endif }; static __init int selinux_init(void) diff --git a/security/selinux/include/classmap.h b/security/selinux/include/classmap.h index 201f7e588a29..f97e7c1db14c 100644 --- a/security/selinux/include/classmap.h +++ b/security/selinux/include/classmap.h @@ -243,6 +243,8 @@ struct security_class_mapping secclass_map[] = { {"map_create", "map_read", "map_write", "prog_load", "prog_run"} }, { "xdp_socket", { COMMON_SOCK_PERMS, NULL } }, + { "perf_event", + {"open", "cpu", "kernel", "tracepoint", "read", "write"} }, { NULL } }; diff --git a/security/selinux/include/objsec.h b/security/selinux/include/objsec.h index cc5e26b0161b..25b69dc17d1b 100644 --- a/security/selinux/include/objsec.h +++ b/security/selinux/include/objsec.h @@ -155,7 +155,11 @@ struct pkey_security_struct { }; struct bpf_security_struct { - u32 sid; /*SID of bpf obj creater*/ + u32 sid; /* SID of bpf obj creator */ +}; + +struct perf_event_security_struct { + u32 sid; /* SID of perf_event obj creator */ }; #endif /* _SELINUX_OBJSEC_H_ */