xiaomi-sm8450/android_kernel_xiaomi_sm8450
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

bpf: Print function name in addition to function id

Browse Source 
The verifier currently prints raw function ids when printing CALL
instructions or when complaining:

	5: (85) call 23
	unknown func 23

print a meaningful function name instead:

	5: (85) call bpf_redirect#23
	unknown func bpf_redirect#23

Moves the function documentation to a single comment and renames all
helpers names in the list to conform to the bpf_ prefix notation so
they can be greped in the kernel source.

Signed-off-by: Thomas Graf <tgraf@suug.ch>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Thomas Graf
2016-10-27 11:23:51 +02:00
committed by David S. Miller
parent 46b5ab1a7c
commit ebb676daa1
2 changed files with 316 additions and 293 deletions
Download Patch File Download Diff File Expand all files Collapse all files

35
kernel/bpf/verifier.c
View File

@@ -19,6 +19,7 @@
#include <net/netlink.h>
#include <linux/file.h>
#include <linux/vmalloc.h>
#include <linux/stringify.h>
/* bpf_check() is a static code analyzer that walks eBPF program
* instruction by instruction and updates register/stack state.
@@ -190,6 +191,22 @@ 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_state *state)
{
struct bpf_reg_state *reg;
@@ -354,7 +371,8 @@ static void print_bpf_insn(struct bpf_insn *insn)
u8 opcode = BPF_OP(insn->code);
if (opcode == BPF_CALL) {
verbose("(%02x) call %d\n", insn->code, insn->imm);
verbose("(%02x) call %s#%d\n", insn->code,
func_id_name(insn->imm), insn->imm);
} else if (insn->code == (BPF_JMP | BPF_JA)) {
verbose("(%02x) goto pc%+d\n",
insn->code, insn->off);
@@ -1114,8 +1132,8 @@ static int check_map_func_compatibility(struct bpf_map *map, int func_id)
return 0;
error:
verbose("cannot pass map_type %d into func %d\n",
map->map_type, func_id);
verbose("cannot pass map_type %d into func %s#%d\n",
map->map_type, func_id_name(func_id), func_id);
return -EINVAL;
}
@@ -1172,7 +1190,7 @@ static int check_call(struct bpf_verifier_env *env, int func_id)
/* find function prototype */
if (func_id < 0 || func_id >= __BPF_FUNC_MAX_ID) {
verbose("invalid func %d\n", func_id);
verbose("invalid func %s#%d\n", func_id_name(func_id), func_id);
return -EINVAL;
}
@@ -1180,7 +1198,7 @@ static int check_call(struct bpf_verifier_env *env, int func_id)
fn = env->prog->aux->ops->get_func_proto(func_id);
if (!fn) {
verbose("unknown func %d\n", func_id);
verbose("unknown func %s#%d\n", func_id_name(func_id), func_id);
return -EINVAL;
}
@@ -1200,7 +1218,8 @@ static int check_call(struct bpf_verifier_env *env, int func_id)
*/
err = check_raw_mode(fn);
if (err) {
verbose("kernel subsystem misconfigured func %d\n", func_id);
verbose("kernel subsystem misconfigured func %s#%d\n",
func_id_name(func_id), func_id);
return err;
}
@@ -1256,8 +1275,8 @@ static int check_call(struct bpf_verifier_env *env, int func_id)
regs[BPF_REG_0].map_ptr = meta.map_ptr;
regs[BPF_REG_0].id = ++env->id_gen;
} else {
verbose("unknown return type %d of func %d\n",
fn->ret_type, func_id);
verbose("unknown return type %d of func %s#%d\n",
fn->ret_type, func_id_name(func_id), func_id);
return -EINVAL;
}