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authorJakub Kicinski <jakub.kicinski@netronome.com>2017-10-09 10:30:12 -0700
committerDavid S. Miller <davem@davemloft.net>2017-10-10 12:30:16 -0700
commitf4ac7e0b5cc8d16004ac57ff679266d573f30f77 (patch)
tree46db6c2ebd91e1fd4316b1775c6381aef1eb5ec5 /kernel/bpf
parent61bd5218eef349fcacc4976a251bc83a4748b4af (diff)
bpf: move instruction printing into a separate file
Separate the instruction printing into a standalone source file. This way sneaky code from tools/ can compile it in directly. Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com> Reviewed-by: Simon Horman <simon.horman@netronome.com> Acked-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'kernel/bpf')
-rw-r--r--kernel/bpf/Makefile1
-rw-r--r--kernel/bpf/disasm.c214
-rw-r--r--kernel/bpf/disasm.h32
-rw-r--r--kernel/bpf/verifier.c202
4 files changed, 251 insertions, 198 deletions
diff --git a/kernel/bpf/Makefile b/kernel/bpf/Makefile
index 897daa005b23..53fb09f92e3f 100644
--- a/kernel/bpf/Makefile
+++ b/kernel/bpf/Makefile
@@ -2,6 +2,7 @@ obj-y := core.o
obj-$(CONFIG_BPF_SYSCALL) += syscall.o verifier.o inode.o helpers.o tnum.o
obj-$(CONFIG_BPF_SYSCALL) += hashtab.o arraymap.o percpu_freelist.o bpf_lru_list.o lpm_trie.o map_in_map.o
+obj-$(CONFIG_BPF_SYSCALL) += disasm.o
ifeq ($(CONFIG_NET),y)
obj-$(CONFIG_BPF_SYSCALL) += devmap.o
ifeq ($(CONFIG_STREAM_PARSER),y)
diff --git a/kernel/bpf/disasm.c b/kernel/bpf/disasm.c
new file mode 100644
index 000000000000..e682850c9715
--- /dev/null
+++ b/kernel/bpf/disasm.c
@@ -0,0 +1,214 @@
+/* Copyright (c) 2011-2014 PLUMgrid, http://plumgrid.com
+ * Copyright (c) 2016 Facebook
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of version 2 of the GNU General Public
+ * License as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ */
+
+#include <linux/bpf.h>
+
+#include "disasm.h"
+
+#define __BPF_FUNC_STR_FN(x) [BPF_FUNC_ ## x] = __stringify(bpf_ ## x)
+static const char * const func_id_str[] = {
+ __BPF_FUNC_MAPPER(__BPF_FUNC_STR_FN)
+};
+#undef __BPF_FUNC_STR_FN
+
+const char *func_id_name(int id)
+{
+ BUILD_BUG_ON(ARRAY_SIZE(func_id_str) != __BPF_FUNC_MAX_ID);
+
+ if (id >= 0 && id < __BPF_FUNC_MAX_ID && func_id_str[id])
+ return func_id_str[id];
+ else
+ return "unknown";
+}
+
+const char *const bpf_class_string[8] = {
+ [BPF_LD] = "ld",
+ [BPF_LDX] = "ldx",
+ [BPF_ST] = "st",
+ [BPF_STX] = "stx",
+ [BPF_ALU] = "alu",
+ [BPF_JMP] = "jmp",
+ [BPF_RET] = "BUG",
+ [BPF_ALU64] = "alu64",
+};
+
+const char *const bpf_alu_string[16] = {
+ [BPF_ADD >> 4] = "+=",
+ [BPF_SUB >> 4] = "-=",
+ [BPF_MUL >> 4] = "*=",
+ [BPF_DIV >> 4] = "/=",
+ [BPF_OR >> 4] = "|=",
+ [BPF_AND >> 4] = "&=",
+ [BPF_LSH >> 4] = "<<=",
+ [BPF_RSH >> 4] = ">>=",
+ [BPF_NEG >> 4] = "neg",
+ [BPF_MOD >> 4] = "%=",
+ [BPF_XOR >> 4] = "^=",
+ [BPF_MOV >> 4] = "=",
+ [BPF_ARSH >> 4] = "s>>=",
+ [BPF_END >> 4] = "endian",
+};
+
+static const char *const bpf_ldst_string[] = {
+ [BPF_W >> 3] = "u32",
+ [BPF_H >> 3] = "u16",
+ [BPF_B >> 3] = "u8",
+ [BPF_DW >> 3] = "u64",
+};
+
+static const char *const bpf_jmp_string[16] = {
+ [BPF_JA >> 4] = "jmp",
+ [BPF_JEQ >> 4] = "==",
+ [BPF_JGT >> 4] = ">",
+ [BPF_JLT >> 4] = "<",
+ [BPF_JGE >> 4] = ">=",
+ [BPF_JLE >> 4] = "<=",
+ [BPF_JSET >> 4] = "&",
+ [BPF_JNE >> 4] = "!=",
+ [BPF_JSGT >> 4] = "s>",
+ [BPF_JSLT >> 4] = "s<",
+ [BPF_JSGE >> 4] = "s>=",
+ [BPF_JSLE >> 4] = "s<=",
+ [BPF_CALL >> 4] = "call",
+ [BPF_EXIT >> 4] = "exit",
+};
+
+static void print_bpf_end_insn(bpf_insn_print_cb verbose,
+ struct bpf_verifier_env *env,
+ const struct bpf_insn *insn)
+{
+ verbose(env, "(%02x) r%d = %s%d r%d\n", insn->code, insn->dst_reg,
+ BPF_SRC(insn->code) == BPF_TO_BE ? "be" : "le",
+ insn->imm, insn->dst_reg);
+}
+
+void print_bpf_insn(bpf_insn_print_cb verbose, struct bpf_verifier_env *env,
+ const struct bpf_insn *insn, bool allow_ptr_leaks)
+{
+ u8 class = BPF_CLASS(insn->code);
+
+ if (class == BPF_ALU || class == BPF_ALU64) {
+ if (BPF_OP(insn->code) == BPF_END) {
+ if (class == BPF_ALU64)
+ verbose(env, "BUG_alu64_%02x\n", insn->code);
+ else
+ print_bpf_end_insn(verbose, env, insn);
+ } else if (BPF_OP(insn->code) == BPF_NEG) {
+ verbose(env, "(%02x) r%d = %s-r%d\n",
+ insn->code, insn->dst_reg,
+ class == BPF_ALU ? "(u32) " : "",
+ insn->dst_reg);
+ } else if (BPF_SRC(insn->code) == BPF_X) {
+ verbose(env, "(%02x) %sr%d %s %sr%d\n",
+ insn->code, class == BPF_ALU ? "(u32) " : "",
+ insn->dst_reg,
+ bpf_alu_string[BPF_OP(insn->code) >> 4],
+ class == BPF_ALU ? "(u32) " : "",
+ insn->src_reg);
+ } else {
+ verbose(env, "(%02x) %sr%d %s %s%d\n",
+ insn->code, class == BPF_ALU ? "(u32) " : "",
+ insn->dst_reg,
+ bpf_alu_string[BPF_OP(insn->code) >> 4],
+ class == BPF_ALU ? "(u32) " : "",
+ insn->imm);
+ }
+ } else if (class == BPF_STX) {
+ if (BPF_MODE(insn->code) == BPF_MEM)
+ verbose(env, "(%02x) *(%s *)(r%d %+d) = r%d\n",
+ insn->code,
+ bpf_ldst_string[BPF_SIZE(insn->code) >> 3],
+ insn->dst_reg,
+ insn->off, insn->src_reg);
+ else if (BPF_MODE(insn->code) == BPF_XADD)
+ verbose(env, "(%02x) lock *(%s *)(r%d %+d) += r%d\n",
+ insn->code,
+ bpf_ldst_string[BPF_SIZE(insn->code) >> 3],
+ insn->dst_reg, insn->off,
+ insn->src_reg);
+ else
+ verbose(env, "BUG_%02x\n", insn->code);
+ } else if (class == BPF_ST) {
+ if (BPF_MODE(insn->code) != BPF_MEM) {
+ verbose(env, "BUG_st_%02x\n", insn->code);
+ return;
+ }
+ verbose(env, "(%02x) *(%s *)(r%d %+d) = %d\n",
+ insn->code,
+ bpf_ldst_string[BPF_SIZE(insn->code) >> 3],
+ insn->dst_reg,
+ insn->off, insn->imm);
+ } else if (class == BPF_LDX) {
+ if (BPF_MODE(insn->code) != BPF_MEM) {
+ verbose(env, "BUG_ldx_%02x\n", insn->code);
+ return;
+ }
+ verbose(env, "(%02x) r%d = *(%s *)(r%d %+d)\n",
+ insn->code, insn->dst_reg,
+ bpf_ldst_string[BPF_SIZE(insn->code) >> 3],
+ insn->src_reg, insn->off);
+ } else if (class == BPF_LD) {
+ if (BPF_MODE(insn->code) == BPF_ABS) {
+ verbose(env, "(%02x) r0 = *(%s *)skb[%d]\n",
+ insn->code,
+ bpf_ldst_string[BPF_SIZE(insn->code) >> 3],
+ insn->imm);
+ } else if (BPF_MODE(insn->code) == BPF_IND) {
+ verbose(env, "(%02x) r0 = *(%s *)skb[r%d + %d]\n",
+ insn->code,
+ bpf_ldst_string[BPF_SIZE(insn->code) >> 3],
+ insn->src_reg, insn->imm);
+ } else if (BPF_MODE(insn->code) == BPF_IMM &&
+ BPF_SIZE(insn->code) == BPF_DW) {
+ /* At this point, we already made sure that the second
+ * part of the ldimm64 insn is accessible.
+ */
+ u64 imm = ((u64)(insn + 1)->imm << 32) | (u32)insn->imm;
+ bool map_ptr = insn->src_reg == BPF_PSEUDO_MAP_FD;
+
+ if (map_ptr && !allow_ptr_leaks)
+ imm = 0;
+
+ verbose(env, "(%02x) r%d = 0x%llx\n", insn->code,
+ insn->dst_reg, (unsigned long long)imm);
+ } else {
+ verbose(env, "BUG_ld_%02x\n", insn->code);
+ return;
+ }
+ } else if (class == BPF_JMP) {
+ u8 opcode = BPF_OP(insn->code);
+
+ if (opcode == BPF_CALL) {
+ verbose(env, "(%02x) call %s#%d\n", insn->code,
+ func_id_name(insn->imm), insn->imm);
+ } else if (insn->code == (BPF_JMP | BPF_JA)) {
+ verbose(env, "(%02x) goto pc%+d\n",
+ insn->code, insn->off);
+ } else if (insn->code == (BPF_JMP | BPF_EXIT)) {
+ verbose(env, "(%02x) exit\n", insn->code);
+ } else if (BPF_SRC(insn->code) == BPF_X) {
+ verbose(env, "(%02x) if r%d %s r%d goto pc%+d\n",
+ insn->code, insn->dst_reg,
+ bpf_jmp_string[BPF_OP(insn->code) >> 4],
+ insn->src_reg, insn->off);
+ } else {
+ verbose(env, "(%02x) if r%d %s 0x%x goto pc%+d\n",
+ insn->code, insn->dst_reg,
+ bpf_jmp_string[BPF_OP(insn->code) >> 4],
+ insn->imm, insn->off);
+ }
+ } else {
+ verbose(env, "(%02x) %s\n",
+ insn->code, bpf_class_string[class]);
+ }
+}
diff --git a/kernel/bpf/disasm.h b/kernel/bpf/disasm.h
new file mode 100644
index 000000000000..8de977e420b6
--- /dev/null
+++ b/kernel/bpf/disasm.h
@@ -0,0 +1,32 @@
+/* Copyright (c) 2011-2014 PLUMgrid, http://plumgrid.com
+ * Copyright (c) 2016 Facebook
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of version 2 of the GNU General Public
+ * License as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ */
+
+#ifndef __BPF_DISASM_H__
+#define __BPF_DISASM_H__
+
+#include <linux/bpf.h>
+#include <linux/kernel.h>
+#include <linux/stringify.h>
+
+extern const char *const bpf_alu_string[16];
+extern const char *const bpf_class_string[8];
+
+const char *func_id_name(int id);
+
+struct bpf_verifier_env;
+typedef void (*bpf_insn_print_cb)(struct bpf_verifier_env *env,
+ const char *, ...);
+void print_bpf_insn(bpf_insn_print_cb verbose, struct bpf_verifier_env *env,
+ const struct bpf_insn *insn, bool allow_ptr_leaks);
+
+#endif
diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c
index a352f93cd4b2..274c6582ec39 100644
--- a/kernel/bpf/verifier.c
+++ b/kernel/bpf/verifier.c
@@ -21,6 +21,8 @@
#include <linux/vmalloc.h>
#include <linux/stringify.h>
+#include "disasm.h"
+
/* bpf_check() is a static code analyzer that walks eBPF program
* instruction by instruction and updates register/stack state.
* All paths of conditional branches are analyzed until 'bpf_exit' insn.
@@ -194,22 +196,6 @@ static const char * const reg_type_str[] = {
[PTR_TO_PACKET_END] = "pkt_end",
};
-#define __BPF_FUNC_STR_FN(x) [BPF_FUNC_ ## x] = __stringify(bpf_ ## x)
-static const char * const func_id_str[] = {
- __BPF_FUNC_MAPPER(__BPF_FUNC_STR_FN)
-};
-#undef __BPF_FUNC_STR_FN
-
-static const char *func_id_name(int id)
-{
- BUILD_BUG_ON(ARRAY_SIZE(func_id_str) != __BPF_FUNC_MAX_ID);
-
- if (id >= 0 && id < __BPF_FUNC_MAX_ID && func_id_str[id])
- return func_id_str[id];
- else
- return "unknown";
-}
-
static void print_verifier_state(struct bpf_verifier_env *env,
struct bpf_verifier_state *state)
{
@@ -278,187 +264,6 @@ static void print_verifier_state(struct bpf_verifier_env *env,
verbose(env, "\n");
}
-static const char *const bpf_class_string[] = {
- [BPF_LD] = "ld",
- [BPF_LDX] = "ldx",
- [BPF_ST] = "st",
- [BPF_STX] = "stx",
- [BPF_ALU] = "alu",
- [BPF_JMP] = "jmp",
- [BPF_RET] = "BUG",
- [BPF_ALU64] = "alu64",
-};
-
-static const char *const bpf_alu_string[16] = {
- [BPF_ADD >> 4] = "+=",
- [BPF_SUB >> 4] = "-=",
- [BPF_MUL >> 4] = "*=",
- [BPF_DIV >> 4] = "/=",
- [BPF_OR >> 4] = "|=",
- [BPF_AND >> 4] = "&=",
- [BPF_LSH >> 4] = "<<=",
- [BPF_RSH >> 4] = ">>=",
- [BPF_NEG >> 4] = "neg",
- [BPF_MOD >> 4] = "%=",
- [BPF_XOR >> 4] = "^=",
- [BPF_MOV >> 4] = "=",
- [BPF_ARSH >> 4] = "s>>=",
- [BPF_END >> 4] = "endian",
-};
-
-static const char *const bpf_ldst_string[] = {
- [BPF_W >> 3] = "u32",
- [BPF_H >> 3] = "u16",
- [BPF_B >> 3] = "u8",
- [BPF_DW >> 3] = "u64",
-};
-
-static const char *const bpf_jmp_string[16] = {
- [BPF_JA >> 4] = "jmp",
- [BPF_JEQ >> 4] = "==",
- [BPF_JGT >> 4] = ">",
- [BPF_JLT >> 4] = "<",
- [BPF_JGE >> 4] = ">=",
- [BPF_JLE >> 4] = "<=",
- [BPF_JSET >> 4] = "&",
- [BPF_JNE >> 4] = "!=",
- [BPF_JSGT >> 4] = "s>",
- [BPF_JSLT >> 4] = "s<",
- [BPF_JSGE >> 4] = "s>=",
- [BPF_JSLE >> 4] = "s<=",
- [BPF_CALL >> 4] = "call",
- [BPF_EXIT >> 4] = "exit",
-};
-
-static void print_bpf_end_insn(struct bpf_verifier_env *env,
- const struct bpf_insn *insn)
-{
- verbose(env, "(%02x) r%d = %s%d r%d\n", insn->code, insn->dst_reg,
- BPF_SRC(insn->code) == BPF_TO_BE ? "be" : "le",
- insn->imm, insn->dst_reg);
-}
-
-static void print_bpf_insn(struct bpf_verifier_env *env,
- const struct bpf_insn *insn)
-{
- u8 class = BPF_CLASS(insn->code);
-
- if (class == BPF_ALU || class == BPF_ALU64) {
- if (BPF_OP(insn->code) == BPF_END) {
- if (class == BPF_ALU64)
- verbose(env, "BUG_alu64_%02x\n", insn->code);
- else
- print_bpf_end_insn(env, insn);
- } else if (BPF_OP(insn->code) == BPF_NEG) {
- verbose(env, "(%02x) r%d = %s-r%d\n",
- insn->code, insn->dst_reg,
- class == BPF_ALU ? "(u32) " : "",
- insn->dst_reg);
- } else if (BPF_SRC(insn->code) == BPF_X) {
- verbose(env, "(%02x) %sr%d %s %sr%d\n",
- insn->code, class == BPF_ALU ? "(u32) " : "",
- insn->dst_reg,
- bpf_alu_string[BPF_OP(insn->code) >> 4],
- class == BPF_ALU ? "(u32) " : "",
- insn->src_reg);
- } else {
- verbose(env, "(%02x) %sr%d %s %s%d\n",
- insn->code, class == BPF_ALU ? "(u32) " : "",
- insn->dst_reg,
- bpf_alu_string[BPF_OP(insn->code) >> 4],
- class == BPF_ALU ? "(u32) " : "",
- insn->imm);
- }
- } else if (class == BPF_STX) {
- if (BPF_MODE(insn->code) == BPF_MEM)
- verbose(env, "(%02x) *(%s *)(r%d %+d) = r%d\n",
- insn->code,
- bpf_ldst_string[BPF_SIZE(insn->code) >> 3],
- insn->dst_reg,
- insn->off, insn->src_reg);
- else if (BPF_MODE(insn->code) == BPF_XADD)
- verbose(env, "(%02x) lock *(%s *)(r%d %+d) += r%d\n",
- insn->code,
- bpf_ldst_string[BPF_SIZE(insn->code) >> 3],
- insn->dst_reg, insn->off,
- insn->src_reg);
- else
- verbose(env, "BUG_%02x\n", insn->code);
- } else if (class == BPF_ST) {
- if (BPF_MODE(insn->code) != BPF_MEM) {
- verbose(env, "BUG_st_%02x\n", insn->code);
- return;
- }
- verbose(env, "(%02x) *(%s *)(r%d %+d) = %d\n",
- insn->code,
- bpf_ldst_string[BPF_SIZE(insn->code) >> 3],
- insn->dst_reg,
- insn->off, insn->imm);
- } else if (class == BPF_LDX) {
- if (BPF_MODE(insn->code) != BPF_MEM) {
- verbose(env, "BUG_ldx_%02x\n", insn->code);
- return;
- }
- verbose(env, "(%02x) r%d = *(%s *)(r%d %+d)\n",
- insn->code, insn->dst_reg,
- bpf_ldst_string[BPF_SIZE(insn->code) >> 3],
- insn->src_reg, insn->off);
- } else if (class == BPF_LD) {
- if (BPF_MODE(insn->code) == BPF_ABS) {
- verbose(env, "(%02x) r0 = *(%s *)skb[%d]\n",
- insn->code,
- bpf_ldst_string[BPF_SIZE(insn->code) >> 3],
- insn->imm);
- } else if (BPF_MODE(insn->code) == BPF_IND) {
- verbose(env, "(%02x) r0 = *(%s *)skb[r%d + %d]\n",
- insn->code,
- bpf_ldst_string[BPF_SIZE(insn->code) >> 3],
- insn->src_reg, insn->imm);
- } else if (BPF_MODE(insn->code) == BPF_IMM &&
- BPF_SIZE(insn->code) == BPF_DW) {
- /* At this point, we already made sure that the second
- * part of the ldimm64 insn is accessible.
- */
- u64 imm = ((u64)(insn + 1)->imm << 32) | (u32)insn->imm;
- bool map_ptr = insn->src_reg == BPF_PSEUDO_MAP_FD;
-
- if (map_ptr && !env->allow_ptr_leaks)
- imm = 0;
-
- verbose(env, "(%02x) r%d = 0x%llx\n", insn->code,
- insn->dst_reg, (unsigned long long)imm);
- } else {
- verbose(env, "BUG_ld_%02x\n", insn->code);
- return;
- }
- } else if (class == BPF_JMP) {
- u8 opcode = BPF_OP(insn->code);
-
- if (opcode == BPF_CALL) {
- verbose(env, "(%02x) call %s#%d\n", insn->code,
- func_id_name(insn->imm), insn->imm);
- } else if (insn->code == (BPF_JMP | BPF_JA)) {
- verbose(env, "(%02x) goto pc%+d\n",
- insn->code, insn->off);
- } else if (insn->code == (BPF_JMP | BPF_EXIT)) {
- verbose(env, "(%02x) exit\n", insn->code);
- } else if (BPF_SRC(insn->code) == BPF_X) {
- verbose(env, "(%02x) if r%d %s r%d goto pc%+d\n",
- insn->code, insn->dst_reg,
- bpf_jmp_string[BPF_OP(insn->code) >> 4],
- insn->src_reg, insn->off);
- } else {
- verbose(env, "(%02x) if r%d %s 0x%x goto pc%+d\n",
- insn->code, insn->dst_reg,
- bpf_jmp_string[BPF_OP(insn->code) >> 4],
- insn->imm, insn->off);
- }
- } else {
- verbose(env, "(%02x) %s\n",
- insn->code, bpf_class_string[class]);
- }
-}
-
static int pop_stack(struct bpf_verifier_env *env, int *prev_insn_idx)
{
struct bpf_verifier_stack_elem *elem;
@@ -3767,7 +3572,8 @@ static int do_check(struct bpf_verifier_env *env)
if (env->log.level) {
verbose(env, "%d: ", insn_idx);
- print_bpf_insn(env, insn);
+ print_bpf_insn(verbose, env, insn,
+ env->allow_ptr_leaks);
}
err = ext_analyzer_insn_hook(env, insn_idx, prev_insn_idx);