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Diffstat (limited to 'kernel/trace/bpf_trace.c')
-rw-r--r--kernel/trace/bpf_trace.c262
1 files changed, 239 insertions, 23 deletions
diff --git a/kernel/trace/bpf_trace.c b/kernel/trace/bpf_trace.c
index c0a9e310d715..d88e96d4e12c 100644
--- a/kernel/trace/bpf_trace.c
+++ b/kernel/trace/bpf_trace.c
@@ -524,7 +524,8 @@ static const struct bpf_func_proto bpf_probe_read_str_proto = {
.arg3_type = ARG_ANYTHING,
};
-static const struct bpf_func_proto *tracing_func_proto(enum bpf_func_id func_id)
+static const struct bpf_func_proto *
+tracing_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
{
switch (func_id) {
case BPF_FUNC_map_lookup_elem:
@@ -568,7 +569,8 @@ static const struct bpf_func_proto *tracing_func_proto(enum bpf_func_id func_id)
}
}
-static const struct bpf_func_proto *kprobe_prog_func_proto(enum bpf_func_id func_id)
+static const struct bpf_func_proto *
+kprobe_prog_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
{
switch (func_id) {
case BPF_FUNC_perf_event_output:
@@ -582,12 +584,13 @@ static const struct bpf_func_proto *kprobe_prog_func_proto(enum bpf_func_id func
return &bpf_override_return_proto;
#endif
default:
- return tracing_func_proto(func_id);
+ return tracing_func_proto(func_id, prog);
}
}
/* bpf+kprobe programs can access fields of 'struct pt_regs' */
static bool kprobe_prog_is_valid_access(int off, int size, enum bpf_access_type type,
+ const struct bpf_prog *prog,
struct bpf_insn_access_aux *info)
{
if (off < 0 || off >= sizeof(struct pt_regs))
@@ -661,7 +664,43 @@ static const struct bpf_func_proto bpf_get_stackid_proto_tp = {
.arg3_type = ARG_ANYTHING,
};
-BPF_CALL_3(bpf_perf_prog_read_value_tp, struct bpf_perf_event_data_kern *, ctx,
+static const struct bpf_func_proto *
+tp_prog_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
+{
+ switch (func_id) {
+ case BPF_FUNC_perf_event_output:
+ return &bpf_perf_event_output_proto_tp;
+ case BPF_FUNC_get_stackid:
+ return &bpf_get_stackid_proto_tp;
+ default:
+ return tracing_func_proto(func_id, prog);
+ }
+}
+
+static bool tp_prog_is_valid_access(int off, int size, enum bpf_access_type type,
+ const struct bpf_prog *prog,
+ struct bpf_insn_access_aux *info)
+{
+ if (off < sizeof(void *) || off >= PERF_MAX_TRACE_SIZE)
+ return false;
+ if (type != BPF_READ)
+ return false;
+ if (off % size != 0)
+ return false;
+
+ BUILD_BUG_ON(PERF_MAX_TRACE_SIZE % sizeof(__u64));
+ return true;
+}
+
+const struct bpf_verifier_ops tracepoint_verifier_ops = {
+ .get_func_proto = tp_prog_func_proto,
+ .is_valid_access = tp_prog_is_valid_access,
+};
+
+const struct bpf_prog_ops tracepoint_prog_ops = {
+};
+
+BPF_CALL_3(bpf_perf_prog_read_value, struct bpf_perf_event_data_kern *, ctx,
struct bpf_perf_event_value *, buf, u32, size)
{
int err = -EINVAL;
@@ -678,8 +717,8 @@ clear:
return err;
}
-static const struct bpf_func_proto bpf_perf_prog_read_value_proto_tp = {
- .func = bpf_perf_prog_read_value_tp,
+static const struct bpf_func_proto bpf_perf_prog_read_value_proto = {
+ .func = bpf_perf_prog_read_value,
.gpl_only = true,
.ret_type = RET_INTEGER,
.arg1_type = ARG_PTR_TO_CTX,
@@ -687,7 +726,8 @@ static const struct bpf_func_proto bpf_perf_prog_read_value_proto_tp = {
.arg3_type = ARG_CONST_SIZE,
};
-static const struct bpf_func_proto *tp_prog_func_proto(enum bpf_func_id func_id)
+static const struct bpf_func_proto *
+pe_prog_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
{
switch (func_id) {
case BPF_FUNC_perf_event_output:
@@ -695,39 +735,99 @@ static const struct bpf_func_proto *tp_prog_func_proto(enum bpf_func_id func_id)
case BPF_FUNC_get_stackid:
return &bpf_get_stackid_proto_tp;
case BPF_FUNC_perf_prog_read_value:
- return &bpf_perf_prog_read_value_proto_tp;
+ return &bpf_perf_prog_read_value_proto;
default:
- return tracing_func_proto(func_id);
+ return tracing_func_proto(func_id, prog);
}
}
-static bool tp_prog_is_valid_access(int off, int size, enum bpf_access_type type,
- struct bpf_insn_access_aux *info)
+/*
+ * bpf_raw_tp_regs are separate from bpf_pt_regs used from skb/xdp
+ * to avoid potential recursive reuse issue when/if tracepoints are added
+ * inside bpf_*_event_output and/or bpf_get_stack_id
+ */
+static DEFINE_PER_CPU(struct pt_regs, bpf_raw_tp_regs);
+BPF_CALL_5(bpf_perf_event_output_raw_tp, struct bpf_raw_tracepoint_args *, args,
+ struct bpf_map *, map, u64, flags, void *, data, u64, size)
{
- if (off < sizeof(void *) || off >= PERF_MAX_TRACE_SIZE)
+ struct pt_regs *regs = this_cpu_ptr(&bpf_raw_tp_regs);
+
+ perf_fetch_caller_regs(regs);
+ return ____bpf_perf_event_output(regs, map, flags, data, size);
+}
+
+static const struct bpf_func_proto bpf_perf_event_output_proto_raw_tp = {
+ .func = bpf_perf_event_output_raw_tp,
+ .gpl_only = true,
+ .ret_type = RET_INTEGER,
+ .arg1_type = ARG_PTR_TO_CTX,
+ .arg2_type = ARG_CONST_MAP_PTR,
+ .arg3_type = ARG_ANYTHING,
+ .arg4_type = ARG_PTR_TO_MEM,
+ .arg5_type = ARG_CONST_SIZE_OR_ZERO,
+};
+
+BPF_CALL_3(bpf_get_stackid_raw_tp, struct bpf_raw_tracepoint_args *, args,
+ struct bpf_map *, map, u64, flags)
+{
+ struct pt_regs *regs = this_cpu_ptr(&bpf_raw_tp_regs);
+
+ perf_fetch_caller_regs(regs);
+ /* similar to bpf_perf_event_output_tp, but pt_regs fetched differently */
+ return bpf_get_stackid((unsigned long) regs, (unsigned long) map,
+ flags, 0, 0);
+}
+
+static const struct bpf_func_proto bpf_get_stackid_proto_raw_tp = {
+ .func = bpf_get_stackid_raw_tp,
+ .gpl_only = true,
+ .ret_type = RET_INTEGER,
+ .arg1_type = ARG_PTR_TO_CTX,
+ .arg2_type = ARG_CONST_MAP_PTR,
+ .arg3_type = ARG_ANYTHING,
+};
+
+static const struct bpf_func_proto *
+raw_tp_prog_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
+{
+ switch (func_id) {
+ case BPF_FUNC_perf_event_output:
+ return &bpf_perf_event_output_proto_raw_tp;
+ case BPF_FUNC_get_stackid:
+ return &bpf_get_stackid_proto_raw_tp;
+ default:
+ return tracing_func_proto(func_id, prog);
+ }
+}
+
+static bool raw_tp_prog_is_valid_access(int off, int size,
+ enum bpf_access_type type,
+ const struct bpf_prog *prog,
+ struct bpf_insn_access_aux *info)
+{
+ /* largest tracepoint in the kernel has 12 args */
+ if (off < 0 || off >= sizeof(__u64) * 12)
return false;
if (type != BPF_READ)
return false;
if (off % size != 0)
return false;
-
- BUILD_BUG_ON(PERF_MAX_TRACE_SIZE % sizeof(__u64));
return true;
}
-const struct bpf_verifier_ops tracepoint_verifier_ops = {
- .get_func_proto = tp_prog_func_proto,
- .is_valid_access = tp_prog_is_valid_access,
+const struct bpf_verifier_ops raw_tracepoint_verifier_ops = {
+ .get_func_proto = raw_tp_prog_func_proto,
+ .is_valid_access = raw_tp_prog_is_valid_access,
};
-const struct bpf_prog_ops tracepoint_prog_ops = {
+const struct bpf_prog_ops raw_tracepoint_prog_ops = {
};
static bool pe_prog_is_valid_access(int off, int size, enum bpf_access_type type,
+ const struct bpf_prog *prog,
struct bpf_insn_access_aux *info)
{
- const int size_sp = FIELD_SIZEOF(struct bpf_perf_event_data,
- sample_period);
+ const int size_u64 = sizeof(u64);
if (off < 0 || off >= sizeof(struct bpf_perf_event_data))
return false;
@@ -738,8 +838,13 @@ static bool pe_prog_is_valid_access(int off, int size, enum bpf_access_type type
switch (off) {
case bpf_ctx_range(struct bpf_perf_event_data, sample_period):
- bpf_ctx_record_field_size(info, size_sp);
- if (!bpf_ctx_narrow_access_ok(off, size, size_sp))
+ bpf_ctx_record_field_size(info, size_u64);
+ if (!bpf_ctx_narrow_access_ok(off, size, size_u64))
+ return false;
+ break;
+ case bpf_ctx_range(struct bpf_perf_event_data, addr):
+ bpf_ctx_record_field_size(info, size_u64);
+ if (!bpf_ctx_narrow_access_ok(off, size, size_u64))
return false;
break;
default:
@@ -766,6 +871,14 @@ static u32 pe_prog_convert_ctx_access(enum bpf_access_type type,
bpf_target_off(struct perf_sample_data, period, 8,
target_size));
break;
+ case offsetof(struct bpf_perf_event_data, addr):
+ *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct bpf_perf_event_data_kern,
+ data), si->dst_reg, si->src_reg,
+ offsetof(struct bpf_perf_event_data_kern, data));
+ *insn++ = BPF_LDX_MEM(BPF_DW, si->dst_reg, si->dst_reg,
+ bpf_target_off(struct perf_sample_data, addr, 8,
+ target_size));
+ break;
default:
*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct bpf_perf_event_data_kern,
regs), si->dst_reg, si->src_reg,
@@ -779,7 +892,7 @@ static u32 pe_prog_convert_ctx_access(enum bpf_access_type type,
}
const struct bpf_verifier_ops perf_event_verifier_ops = {
- .get_func_proto = tp_prog_func_proto,
+ .get_func_proto = pe_prog_func_proto,
.is_valid_access = pe_prog_is_valid_access,
.convert_ctx_access = pe_prog_convert_ctx_access,
};
@@ -884,3 +997,106 @@ int perf_event_query_prog_array(struct perf_event *event, void __user *info)
return ret;
}
+
+extern struct bpf_raw_event_map __start__bpf_raw_tp[];
+extern struct bpf_raw_event_map __stop__bpf_raw_tp[];
+
+struct bpf_raw_event_map *bpf_find_raw_tracepoint(const char *name)
+{
+ struct bpf_raw_event_map *btp = __start__bpf_raw_tp;
+
+ for (; btp < __stop__bpf_raw_tp; btp++) {
+ if (!strcmp(btp->tp->name, name))
+ return btp;
+ }
+ return NULL;
+}
+
+static __always_inline
+void __bpf_trace_run(struct bpf_prog *prog, u64 *args)
+{
+ rcu_read_lock();
+ preempt_disable();
+ (void) BPF_PROG_RUN(prog, args);
+ preempt_enable();
+ rcu_read_unlock();
+}
+
+#define UNPACK(...) __VA_ARGS__
+#define REPEAT_1(FN, DL, X, ...) FN(X)
+#define REPEAT_2(FN, DL, X, ...) FN(X) UNPACK DL REPEAT_1(FN, DL, __VA_ARGS__)
+#define REPEAT_3(FN, DL, X, ...) FN(X) UNPACK DL REPEAT_2(FN, DL, __VA_ARGS__)
+#define REPEAT_4(FN, DL, X, ...) FN(X) UNPACK DL REPEAT_3(FN, DL, __VA_ARGS__)
+#define REPEAT_5(FN, DL, X, ...) FN(X) UNPACK DL REPEAT_4(FN, DL, __VA_ARGS__)
+#define REPEAT_6(FN, DL, X, ...) FN(X) UNPACK DL REPEAT_5(FN, DL, __VA_ARGS__)
+#define REPEAT_7(FN, DL, X, ...) FN(X) UNPACK DL REPEAT_6(FN, DL, __VA_ARGS__)
+#define REPEAT_8(FN, DL, X, ...) FN(X) UNPACK DL REPEAT_7(FN, DL, __VA_ARGS__)
+#define REPEAT_9(FN, DL, X, ...) FN(X) UNPACK DL REPEAT_8(FN, DL, __VA_ARGS__)
+#define REPEAT_10(FN, DL, X, ...) FN(X) UNPACK DL REPEAT_9(FN, DL, __VA_ARGS__)
+#define REPEAT_11(FN, DL, X, ...) FN(X) UNPACK DL REPEAT_10(FN, DL, __VA_ARGS__)
+#define REPEAT_12(FN, DL, X, ...) FN(X) UNPACK DL REPEAT_11(FN, DL, __VA_ARGS__)
+#define REPEAT(X, FN, DL, ...) REPEAT_##X(FN, DL, __VA_ARGS__)
+
+#define SARG(X) u64 arg##X
+#define COPY(X) args[X] = arg##X
+
+#define __DL_COM (,)
+#define __DL_SEM (;)
+
+#define __SEQ_0_11 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11
+
+#define BPF_TRACE_DEFN_x(x) \
+ void bpf_trace_run##x(struct bpf_prog *prog, \
+ REPEAT(x, SARG, __DL_COM, __SEQ_0_11)) \
+ { \
+ u64 args[x]; \
+ REPEAT(x, COPY, __DL_SEM, __SEQ_0_11); \
+ __bpf_trace_run(prog, args); \
+ } \
+ EXPORT_SYMBOL_GPL(bpf_trace_run##x)
+BPF_TRACE_DEFN_x(1);
+BPF_TRACE_DEFN_x(2);
+BPF_TRACE_DEFN_x(3);
+BPF_TRACE_DEFN_x(4);
+BPF_TRACE_DEFN_x(5);
+BPF_TRACE_DEFN_x(6);
+BPF_TRACE_DEFN_x(7);
+BPF_TRACE_DEFN_x(8);
+BPF_TRACE_DEFN_x(9);
+BPF_TRACE_DEFN_x(10);
+BPF_TRACE_DEFN_x(11);
+BPF_TRACE_DEFN_x(12);
+
+static int __bpf_probe_register(struct bpf_raw_event_map *btp, struct bpf_prog *prog)
+{
+ struct tracepoint *tp = btp->tp;
+
+ /*
+ * check that program doesn't access arguments beyond what's
+ * available in this tracepoint
+ */
+ if (prog->aux->max_ctx_offset > btp->num_args * sizeof(u64))
+ return -EINVAL;
+
+ return tracepoint_probe_register(tp, (void *)btp->bpf_func, prog);
+}
+
+int bpf_probe_register(struct bpf_raw_event_map *btp, struct bpf_prog *prog)
+{
+ int err;
+
+ mutex_lock(&bpf_event_mutex);
+ err = __bpf_probe_register(btp, prog);
+ mutex_unlock(&bpf_event_mutex);
+ return err;
+}
+
+int bpf_probe_unregister(struct bpf_raw_event_map *btp, struct bpf_prog *prog)
+{
+ int err;
+
+ mutex_lock(&bpf_event_mutex);
+ err = tracepoint_probe_unregister(btp->tp, (void *)btp->bpf_func, prog);
+ mutex_unlock(&bpf_event_mutex);
+ return err;
+}