diff options
| -rw-r--r-- | kernel/trace/trace_kprobe.c | 115 |
1 files changed, 73 insertions, 42 deletions
diff --git a/kernel/trace/trace_kprobe.c b/kernel/trace/trace_kprobe.c index 09cba270392d..97309d4714f7 100644 --- a/kernel/trace/trace_kprobe.c +++ b/kernel/trace/trace_kprobe.c @@ -1149,35 +1149,49 @@ static __kprobes int kprobe_profile_func(struct kprobe *kp, struct trace_probe *tp = container_of(kp, struct trace_probe, rp.kp); struct ftrace_event_call *call = &tp->call; struct kprobe_trace_entry *entry; - int size, __size, i, pc; + struct trace_entry *ent; + int size, __size, i, pc, __cpu; unsigned long irq_flags; + char *raw_data; - local_save_flags(irq_flags); pc = preempt_count(); - __size = SIZEOF_KPROBE_TRACE_ENTRY(tp->nr_args); size = ALIGN(__size + sizeof(u32), sizeof(u64)); size -= sizeof(u32); + if (WARN_ONCE(size > FTRACE_MAX_PROFILE_SIZE, + "profile buffer not large enough")) + return 0; - do { - char raw_data[size]; - struct trace_entry *ent; - /* - * Zero dead bytes from alignment to avoid stack leak - * to userspace - */ - *(u64 *)(&raw_data[size - sizeof(u64)]) = 0ULL; - entry = (struct kprobe_trace_entry *)raw_data; - ent = &entry->ent; - - tracing_generic_entry_update(ent, irq_flags, pc); - ent->type = call->id; - entry->nargs = tp->nr_args; - entry->ip = (unsigned long)kp->addr; - for (i = 0; i < tp->nr_args; i++) - entry->args[i] = call_fetch(&tp->args[i].fetch, regs); - perf_tp_event(call->id, entry->ip, 1, entry, size); - } while (0); + /* + * Protect the non nmi buffer + * This also protects the rcu read side + */ + local_irq_save(irq_flags); + __cpu = smp_processor_id(); + + if (in_nmi()) + raw_data = rcu_dereference(trace_profile_buf_nmi); + else + raw_data = rcu_dereference(trace_profile_buf); + + if (!raw_data) + goto end; + + raw_data = per_cpu_ptr(raw_data, __cpu); + /* Zero dead bytes from alignment to avoid buffer leak to userspace */ + *(u64 *)(&raw_data[size - sizeof(u64)]) = 0ULL; + entry = (struct kprobe_trace_entry *)raw_data; + ent = &entry->ent; + + tracing_generic_entry_update(ent, irq_flags, pc); + ent->type = call->id; + entry->nargs = tp->nr_args; + entry->ip = (unsigned long)kp->addr; + for (i = 0; i < tp->nr_args; i++) + entry->args[i] = call_fetch(&tp->args[i].fetch, regs); + perf_tp_event(call->id, entry->ip, 1, entry, size); +end: + local_irq_restore(irq_flags); return 0; } @@ -1188,33 +1202,50 @@ static __kprobes int kretprobe_profile_func(struct kretprobe_instance *ri, struct trace_probe *tp = container_of(ri->rp, struct trace_probe, rp); struct ftrace_event_call *call = &tp->call; struct kretprobe_trace_entry *entry; - int size, __size, i, pc; + struct trace_entry *ent; + int size, __size, i, pc, __cpu; unsigned long irq_flags; + char *raw_data; - local_save_flags(irq_flags); pc = preempt_count(); - __size = SIZEOF_KRETPROBE_TRACE_ENTRY(tp->nr_args); size = ALIGN(__size + sizeof(u32), sizeof(u64)); size -= sizeof(u32); + if (WARN_ONCE(size > FTRACE_MAX_PROFILE_SIZE, + "profile buffer not large enough")) + return 0; + + /* + * Protect the non nmi buffer + * This also protects the rcu read side + */ + local_irq_save(irq_flags); + __cpu = smp_processor_id(); + + if (in_nmi()) + raw_data = rcu_dereference(trace_profile_buf_nmi); + else + raw_data = rcu_dereference(trace_profile_buf); + + if (!raw_data) + goto end; + + raw_data = per_cpu_ptr(raw_data, __cpu); + /* Zero dead bytes from alignment to avoid buffer leak to userspace */ + *(u64 *)(&raw_data[size - sizeof(u64)]) = 0ULL; + entry = (struct kretprobe_trace_entry *)raw_data; + ent = &entry->ent; - do { - char raw_data[size]; - struct trace_entry *ent; - - *(u64 *)(&raw_data[size - sizeof(u64)]) = 0ULL; - entry = (struct kretprobe_trace_entry *)raw_data; - ent = &entry->ent; - - tracing_generic_entry_update(ent, irq_flags, pc); - ent->type = call->id; - entry->nargs = tp->nr_args; - entry->func = (unsigned long)tp->rp.kp.addr; - entry->ret_ip = (unsigned long)ri->ret_addr; - for (i = 0; i < tp->nr_args; i++) - entry->args[i] = call_fetch(&tp->args[i].fetch, regs); - perf_tp_event(call->id, entry->ret_ip, 1, entry, size); - } while (0); + tracing_generic_entry_update(ent, irq_flags, pc); + ent->type = call->id; + entry->nargs = tp->nr_args; + entry->func = (unsigned long)tp->rp.kp.addr; + entry->ret_ip = (unsigned long)ri->ret_addr; + for (i = 0; i < tp->nr_args; i++) + entry->args[i] = call_fetch(&tp->args[i].fetch, regs); + perf_tp_event(call->id, entry->ret_ip, 1, entry, size); +end: + local_irq_restore(irq_flags); return 0; } |
