Merge branch 'bpf-cb-access'

Daniel Borkmann says:

====================
More flexible BPF cb access

This patch improves BPF's cb access by allowing b/h/w/dw
access variants on it. For details, please see individual
patches.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

include/linux/bpf.h

@@ -161,9 +161,10 @@ struct bpf_verifier_ops {
 				enum bpf_reg_type *reg_type);
 	int (*gen_prologue)(struct bpf_insn *insn, bool direct_write,
 			    const struct bpf_prog *prog);
-	u32 (*convert_ctx_access)(enum bpf_access_type type, int dst_reg,
-				  int src_reg, int ctx_off,
-				  struct bpf_insn *insn, struct bpf_prog *prog);
+	u32 (*convert_ctx_access)(enum bpf_access_type type,
+				  const struct bpf_insn *src,
+				  struct bpf_insn *dst,
+				  struct bpf_prog *prog);
 };
 
 struct bpf_prog_type_list {

kernel/bpf/verifier.c

@@ -3165,10 +3165,14 @@ static int convert_ctx_accesses(struct bpf_verifier_env *env)
 	insn = env->prog->insnsi + delta;
 
 	for (i = 0; i < insn_cnt; i++, insn++) {
-		if (insn->code == (BPF_LDX | BPF_MEM | BPF_W) ||
+		if (insn->code == (BPF_LDX | BPF_MEM | BPF_B) ||
+		    insn->code == (BPF_LDX | BPF_MEM | BPF_H) ||
+		    insn->code == (BPF_LDX | BPF_MEM | BPF_W) ||
 		    insn->code == (BPF_LDX | BPF_MEM | BPF_DW))
 			type = BPF_READ;
-		else if (insn->code == (BPF_STX | BPF_MEM | BPF_W) ||
+		else if (insn->code == (BPF_STX | BPF_MEM | BPF_B) ||
+			 insn->code == (BPF_STX | BPF_MEM | BPF_H) ||
+			 insn->code == (BPF_STX | BPF_MEM | BPF_W) ||
 			 insn->code == (BPF_STX | BPF_MEM | BPF_DW))
 			type = BPF_WRITE;
 		else
@@ -3177,8 +3181,7 @@ static int convert_ctx_accesses(struct bpf_verifier_env *env)
 		if (env->insn_aux_data[i].ptr_type != PTR_TO_CTX)
 			continue;
 
-		cnt = ops->convert_ctx_access(type, insn->dst_reg, insn->src_reg,
-					      insn->off, insn_buf, env->prog);
+		cnt = ops->convert_ctx_access(type, insn, insn_buf, env->prog);
 		if (cnt == 0 || cnt >= ARRAY_SIZE(insn_buf)) {
 			verbose("bpf verifier is misconfigured\n");
 			return -EINVAL;

kernel/trace/bpf_trace.c

@@ -572,28 +572,29 @@ static bool pe_prog_is_valid_access(int off, int size, enum bpf_access_type type
 	return true;
 }
 
-static u32 pe_prog_convert_ctx_access(enum bpf_access_type type, int dst_reg,
-				      int src_reg, int ctx_off,
+static u32 pe_prog_convert_ctx_access(enum bpf_access_type type,
+				      const struct bpf_insn *si,
 				      struct bpf_insn *insn_buf,
 				      struct bpf_prog *prog)
 {
 	struct bpf_insn *insn = insn_buf;
 
-	switch (ctx_off) {
+	switch (si->off) {
 	case offsetof(struct bpf_perf_event_data, sample_period):
 		BUILD_BUG_ON(FIELD_SIZEOF(struct perf_sample_data, period) != sizeof(u64));
 
 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct bpf_perf_event_data_kern,
-						       data), dst_reg, src_reg,
+						       data), si->dst_reg, si->src_reg,
 				      offsetof(struct bpf_perf_event_data_kern, data));
-		*insn++ = BPF_LDX_MEM(BPF_DW, dst_reg, dst_reg,
+		*insn++ = BPF_LDX_MEM(BPF_DW, si->dst_reg, si->dst_reg,
 				      offsetof(struct perf_sample_data, period));
 		break;
 	default:
 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct bpf_perf_event_data_kern,
-						       regs), dst_reg, src_reg,
+						       regs), si->dst_reg, si->src_reg,
 				      offsetof(struct bpf_perf_event_data_kern, regs));
-		*insn++ = BPF_LDX_MEM(BPF_SIZEOF(long), dst_reg, dst_reg, ctx_off);
+		*insn++ = BPF_LDX_MEM(BPF_SIZEOF(long), si->dst_reg, si->dst_reg,
+				      si->off);
 		break;
 	}