1 files changed, 24 insertions, 15 deletions

diff --git a/kernel/trace/bpf_trace.c b/kernel/trace/bpf_trace.c
index a5580c670866..40207c2a4113 100644
--- a/kernel/trace/bpf_trace.c
+++ b/kernel/trace/bpf_trace.c
@@ -78,16 +78,12 @@ EXPORT_SYMBOL_GPL(trace_call_bpf);
 
 BPF_CALL_3(bpf_probe_read, void *, dst, u32, size, const void *, unsafe_ptr)
 {
-	int ret = 0;
-
-	if (unlikely(size == 0))
-		goto out;
+	int ret;
 
 	ret = probe_kernel_read(dst, unsafe_ptr, size);
 	if (unlikely(ret < 0))
 		memset(dst, 0, size);
 
- out:
 	return ret;
 }
 
@@ -347,14 +343,13 @@ static const struct bpf_func_proto bpf_perf_event_read_value_proto = {
 	.arg4_type	= ARG_CONST_SIZE,
 };
 
-static DEFINE_PER_CPU(struct perf_sample_data, bpf_sd);
+static DEFINE_PER_CPU(struct perf_sample_data, bpf_trace_sd);
 
 static __always_inline u64
 __bpf_perf_event_output(struct pt_regs *regs, struct bpf_map *map,
-			u64 flags, struct perf_raw_record *raw)
+			u64 flags, struct perf_sample_data *sd)
 {
 	struct bpf_array *array = container_of(map, struct bpf_array, map);
-	struct perf_sample_data *sd = this_cpu_ptr(&bpf_sd);
 	unsigned int cpu = smp_processor_id();
 	u64 index = flags & BPF_F_INDEX_MASK;
 	struct bpf_event_entry *ee;
@@ -377,8 +372,6 @@ __bpf_perf_event_output(struct pt_regs *regs, struct bpf_map *map,
 	if (unlikely(event->oncpu != cpu))
 		return -EOPNOTSUPP;
 
-	perf_sample_data_init(sd, 0, 0);
-	sd->raw = raw;
 	perf_event_output(event, sd, regs);
 	return 0;
 }
@@ -386,6 +379,7 @@ __bpf_perf_event_output(struct pt_regs *regs, struct bpf_map *map,
 BPF_CALL_5(bpf_perf_event_output, struct pt_regs *, regs, struct bpf_map *, map,
 	   u64, flags, void *, data, u64, size)
 {
+	struct perf_sample_data *sd = this_cpu_ptr(&bpf_trace_sd);
 	struct perf_raw_record raw = {
 		.frag = {
 			.size = size,
@@ -396,7 +390,10 @@ BPF_CALL_5(bpf_perf_event_output, struct pt_regs *, regs, struct bpf_map *, map,
 	if (unlikely(flags & ~(BPF_F_INDEX_MASK)))
 		return -EINVAL;
 
-	return __bpf_perf_event_output(regs, map, flags, &raw);
+	perf_sample_data_init(sd, 0, 0);
+	sd->raw = &raw;
+
+	return __bpf_perf_event_output(regs, map, flags, sd);
 }
 
 static const struct bpf_func_proto bpf_perf_event_output_proto = {
@@ -407,14 +404,16 @@ static const struct bpf_func_proto bpf_perf_event_output_proto = {
 	.arg2_type	= ARG_CONST_MAP_PTR,
 	.arg3_type	= ARG_ANYTHING,
 	.arg4_type	= ARG_PTR_TO_MEM,
-	.arg5_type	= ARG_CONST_SIZE,
+	.arg5_type	= ARG_CONST_SIZE_OR_ZERO,
 };
 
 static DEFINE_PER_CPU(struct pt_regs, bpf_pt_regs);
+static DEFINE_PER_CPU(struct perf_sample_data, bpf_misc_sd);
 
 u64 bpf_event_output(struct bpf_map *map, u64 flags, void *meta, u64 meta_size,
 		     void *ctx, u64 ctx_size, bpf_ctx_copy_t ctx_copy)
 {
+	struct perf_sample_data *sd = this_cpu_ptr(&bpf_misc_sd);
 	struct pt_regs *regs = this_cpu_ptr(&bpf_pt_regs);
 	struct perf_raw_frag frag = {
 		.copy		= ctx_copy,
@@ -432,8 +431,10 @@ u64 bpf_event_output(struct bpf_map *map, u64 flags, void *meta, u64 meta_size,
 	};
 
 	perf_fetch_caller_regs(regs);
+	perf_sample_data_init(sd, 0, 0);
+	sd->raw = &raw;
 
-	return __bpf_perf_event_output(regs, map, flags, &raw);
+	return __bpf_perf_event_output(regs, map, flags, sd);
 }
 
 BPF_CALL_0(bpf_get_current_task)
@@ -498,7 +499,7 @@ static const struct bpf_func_proto bpf_probe_read_str_proto = {
 	.gpl_only	= true,
 	.ret_type	= RET_INTEGER,
 	.arg1_type	= ARG_PTR_TO_UNINIT_MEM,
-	.arg2_type	= ARG_CONST_SIZE,
+	.arg2_type	= ARG_CONST_SIZE_OR_ZERO,
 	.arg3_type	= ARG_ANYTHING,
 };
 
@@ -609,7 +610,7 @@ static const struct bpf_func_proto bpf_perf_event_output_proto_tp = {
 	.arg2_type	= ARG_CONST_MAP_PTR,
 	.arg3_type	= ARG_ANYTHING,
 	.arg4_type	= ARG_PTR_TO_MEM,
-	.arg5_type	= ARG_CONST_SIZE,
+	.arg5_type	= ARG_CONST_SIZE_OR_ZERO,
 };
 
 BPF_CALL_3(bpf_get_stackid_tp, void *, tp_buff, struct bpf_map *, map,
@@ -763,6 +764,8 @@ const struct bpf_prog_ops perf_event_prog_ops = {
 
 static DEFINE_MUTEX(bpf_event_mutex);
 
+#define BPF_TRACE_MAX_PROGS 64
+
 int perf_event_attach_bpf_prog(struct perf_event *event,
 			       struct bpf_prog *prog)
 {
@@ -776,6 +779,12 @@ int perf_event_attach_bpf_prog(struct perf_event *event,
 		goto unlock;
 
 	old_array = event->tp_event->prog_array;
+	if (old_array &&
+	    bpf_prog_array_length(old_array) >= BPF_TRACE_MAX_PROGS) {
+		ret = -E2BIG;
+		goto unlock;
+	}
+
 	ret = bpf_prog_array_copy(old_array, NULL, prog, &new_array);
 	if (ret < 0)
 		goto unlock;