bpf: remove global variables

Move three global variables protected by bpf_verifier_lock into
'struct bpf_verifier_env' to allow parallel verification.

Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
This commit is contained in:
Alexei Starovoitov 2019-04-19 07:44:54 -07:00 committed by Daniel Borkmann
parent 3b8802446d
commit 7df737e991
2 changed files with 18 additions and 12 deletions

View File

@ -295,6 +295,11 @@ struct bpf_verifier_env {
const struct bpf_line_info *prev_linfo;
struct bpf_verifier_log log;
struct bpf_subprog_info subprog_info[BPF_MAX_SUBPROGS + 1];
struct {
int *insn_state;
int *insn_stack;
int cur_stack;
} cfg;
u32 subprog_cnt;
/* number of instructions analyzed by the verifier */
u32 insn_processed;

View File

@ -5369,10 +5369,6 @@ enum {
#define STATE_LIST_MARK ((struct bpf_verifier_state_list *) -1L)
static int *insn_stack; /* stack of insns to process */
static int cur_stack; /* current stack index */
static int *insn_state;
/* t, w, e - match pseudo-code above:
* t - index of current instruction
* w - next instruction
@ -5380,6 +5376,9 @@ static int *insn_state;
*/
static int push_insn(int t, int w, int e, struct bpf_verifier_env *env)
{
int *insn_stack = env->cfg.insn_stack;
int *insn_state = env->cfg.insn_state;
if (e == FALLTHROUGH && insn_state[t] >= (DISCOVERED | FALLTHROUGH))
return 0;
@ -5400,9 +5399,9 @@ static int push_insn(int t, int w, int e, struct bpf_verifier_env *env)
/* tree-edge */
insn_state[t] = DISCOVERED | e;
insn_state[w] = DISCOVERED;
if (cur_stack >= env->prog->len)
if (env->cfg.cur_stack >= env->prog->len)
return -E2BIG;
insn_stack[cur_stack++] = w;
insn_stack[env->cfg.cur_stack++] = w;
return 1;
} else if ((insn_state[w] & 0xF0) == DISCOVERED) {
verbose_linfo(env, t, "%d: ", t);
@ -5426,14 +5425,15 @@ static int check_cfg(struct bpf_verifier_env *env)
{
struct bpf_insn *insns = env->prog->insnsi;
int insn_cnt = env->prog->len;
int *insn_stack, *insn_state;
int ret = 0;
int i, t;
insn_state = kvcalloc(insn_cnt, sizeof(int), GFP_KERNEL);
insn_state = env->cfg.insn_state = kvcalloc(insn_cnt, sizeof(int), GFP_KERNEL);
if (!insn_state)
return -ENOMEM;
insn_stack = kvcalloc(insn_cnt, sizeof(int), GFP_KERNEL);
insn_stack = env->cfg.insn_stack = kvcalloc(insn_cnt, sizeof(int), GFP_KERNEL);
if (!insn_stack) {
kvfree(insn_state);
return -ENOMEM;
@ -5441,12 +5441,12 @@ static int check_cfg(struct bpf_verifier_env *env)
insn_state[0] = DISCOVERED; /* mark 1st insn as discovered */
insn_stack[0] = 0; /* 0 is the first instruction */
cur_stack = 1;
env->cfg.cur_stack = 1;
peek_stack:
if (cur_stack == 0)
if (env->cfg.cur_stack == 0)
goto check_state;
t = insn_stack[cur_stack - 1];
t = insn_stack[env->cfg.cur_stack - 1];
if (BPF_CLASS(insns[t].code) == BPF_JMP ||
BPF_CLASS(insns[t].code) == BPF_JMP32) {
@ -5515,7 +5515,7 @@ peek_stack:
mark_explored:
insn_state[t] = EXPLORED;
if (cur_stack-- <= 0) {
if (env->cfg.cur_stack-- <= 0) {
verbose(env, "pop stack internal bug\n");
ret = -EFAULT;
goto err_free;
@ -5535,6 +5535,7 @@ check_state:
err_free:
kvfree(insn_state);
kvfree(insn_stack);
env->cfg.insn_state = env->cfg.insn_stack = NULL;
return ret;
}