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-rw-r--r--include/linux/bpf_verifier.h5
-rw-r--r--kernel/bpf/verifier.c25
2 files changed, 18 insertions, 12 deletions
diff --git a/include/linux/bpf_verifier.h b/include/linux/bpf_verifier.h
index b3ab61fe1932..1305ccbd8fe6 100644
--- a/include/linux/bpf_verifier.h
+++ b/include/linux/bpf_verifier.h
@@ -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;
diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c
index db301e9b5295..5f0eb5bd5589 100644
--- a/kernel/bpf/verifier.c
+++ b/kernel/bpf/verifier.c
@@ -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;
}