summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
-rw-r--r--include/linux/bpf_verifier.h2
-rw-r--r--kernel/bpf/verifier.c86
-rw-r--r--tools/testing/selftests/bpf/config2
-rw-r--r--tools/testing/selftests/net/reuseport_bpf_numa.c4
4 files changed, 70 insertions, 24 deletions
diff --git a/include/linux/bpf_verifier.h b/include/linux/bpf_verifier.h
index 7e61c395fddf..52fb077d3c45 100644
--- a/include/linux/bpf_verifier.h
+++ b/include/linux/bpf_verifier.h
@@ -142,7 +142,7 @@ struct bpf_verifier_state_list {
struct bpf_insn_aux_data {
union {
enum bpf_reg_type ptr_type; /* pointer type for load/store insns */
- struct bpf_map *map_ptr; /* pointer for call insn into lookup_elem */
+ unsigned long map_state; /* pointer/poison value for maps */
s32 call_imm; /* saved imm field of call insn */
};
int ctx_field_size; /* the ctx field size for load insn, maybe 0 */
diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c
index 5dd1dcb902bf..dcebf3f7365c 100644
--- a/kernel/bpf/verifier.c
+++ b/kernel/bpf/verifier.c
@@ -156,7 +156,29 @@ struct bpf_verifier_stack_elem {
#define BPF_COMPLEXITY_LIMIT_INSNS 131072
#define BPF_COMPLEXITY_LIMIT_STACK 1024
-#define BPF_MAP_PTR_POISON ((void *)0xeB9F + POISON_POINTER_DELTA)
+#define BPF_MAP_PTR_UNPRIV 1UL
+#define BPF_MAP_PTR_POISON ((void *)((0xeB9FUL << 1) + \
+ POISON_POINTER_DELTA))
+#define BPF_MAP_PTR(X) ((struct bpf_map *)((X) & ~BPF_MAP_PTR_UNPRIV))
+
+static bool bpf_map_ptr_poisoned(const struct bpf_insn_aux_data *aux)
+{
+ return BPF_MAP_PTR(aux->map_state) == BPF_MAP_PTR_POISON;
+}
+
+static bool bpf_map_ptr_unpriv(const struct bpf_insn_aux_data *aux)
+{
+ return aux->map_state & BPF_MAP_PTR_UNPRIV;
+}
+
+static void bpf_map_ptr_store(struct bpf_insn_aux_data *aux,
+ const struct bpf_map *map, bool unpriv)
+{
+ BUILD_BUG_ON((unsigned long)BPF_MAP_PTR_POISON & BPF_MAP_PTR_UNPRIV);
+ unpriv |= bpf_map_ptr_unpriv(aux);
+ aux->map_state = (unsigned long)map |
+ (unpriv ? BPF_MAP_PTR_UNPRIV : 0UL);
+}
struct bpf_call_arg_meta {
struct bpf_map *map_ptr;
@@ -2333,6 +2355,29 @@ static int prepare_func_exit(struct bpf_verifier_env *env, int *insn_idx)
return 0;
}
+static int
+record_func_map(struct bpf_verifier_env *env, struct bpf_call_arg_meta *meta,
+ int func_id, int insn_idx)
+{
+ struct bpf_insn_aux_data *aux = &env->insn_aux_data[insn_idx];
+
+ if (func_id != BPF_FUNC_tail_call &&
+ func_id != BPF_FUNC_map_lookup_elem)
+ return 0;
+ if (meta->map_ptr == NULL) {
+ verbose(env, "kernel subsystem misconfigured verifier\n");
+ return -EINVAL;
+ }
+
+ if (!BPF_MAP_PTR(aux->map_state))
+ bpf_map_ptr_store(aux, meta->map_ptr,
+ meta->map_ptr->unpriv_array);
+ else if (BPF_MAP_PTR(aux->map_state) != meta->map_ptr)
+ bpf_map_ptr_store(aux, BPF_MAP_PTR_POISON,
+ meta->map_ptr->unpriv_array);
+ return 0;
+}
+
static int check_helper_call(struct bpf_verifier_env *env, int func_id, int insn_idx)
{
const struct bpf_func_proto *fn = NULL;
@@ -2387,13 +2432,6 @@ static int check_helper_call(struct bpf_verifier_env *env, int func_id, int insn
err = check_func_arg(env, BPF_REG_2, fn->arg2_type, &meta);
if (err)
return err;
- if (func_id == BPF_FUNC_tail_call) {
- if (meta.map_ptr == NULL) {
- verbose(env, "verifier bug\n");
- return -EINVAL;
- }
- env->insn_aux_data[insn_idx].map_ptr = meta.map_ptr;
- }
err = check_func_arg(env, BPF_REG_3, fn->arg3_type, &meta);
if (err)
return err;
@@ -2404,6 +2442,10 @@ static int check_helper_call(struct bpf_verifier_env *env, int func_id, int insn
if (err)
return err;
+ err = record_func_map(env, &meta, func_id, insn_idx);
+ if (err)
+ return err;
+
/* Mark slots with STACK_MISC in case of raw mode, stack offset
* is inferred from register state.
*/
@@ -2428,8 +2470,6 @@ static int check_helper_call(struct bpf_verifier_env *env, int func_id, int insn
} else if (fn->ret_type == RET_VOID) {
regs[BPF_REG_0].type = NOT_INIT;
} else if (fn->ret_type == RET_PTR_TO_MAP_VALUE_OR_NULL) {
- struct bpf_insn_aux_data *insn_aux;
-
regs[BPF_REG_0].type = PTR_TO_MAP_VALUE_OR_NULL;
/* There is no offset yet applied, variable or fixed */
mark_reg_known_zero(env, regs, BPF_REG_0);
@@ -2445,11 +2485,6 @@ static int check_helper_call(struct bpf_verifier_env *env, int func_id, int insn
}
regs[BPF_REG_0].map_ptr = meta.map_ptr;
regs[BPF_REG_0].id = ++env->id_gen;
- insn_aux = &env->insn_aux_data[insn_idx];
- if (!insn_aux->map_ptr)
- insn_aux->map_ptr = meta.map_ptr;
- else if (insn_aux->map_ptr != meta.map_ptr)
- insn_aux->map_ptr = BPF_MAP_PTR_POISON;
} else {
verbose(env, "unknown return type %d of func %s#%d\n",
fn->ret_type, func_id_name(func_id), func_id);
@@ -5417,6 +5452,7 @@ static int fixup_bpf_calls(struct bpf_verifier_env *env)
struct bpf_insn *insn = prog->insnsi;
const struct bpf_func_proto *fn;
const int insn_cnt = prog->len;
+ struct bpf_insn_aux_data *aux;
struct bpf_insn insn_buf[16];
struct bpf_prog *new_prog;
struct bpf_map *map_ptr;
@@ -5491,19 +5527,22 @@ static int fixup_bpf_calls(struct bpf_verifier_env *env)
insn->imm = 0;
insn->code = BPF_JMP | BPF_TAIL_CALL;
+ aux = &env->insn_aux_data[i + delta];
+ if (!bpf_map_ptr_unpriv(aux))
+ continue;
+
/* instead of changing every JIT dealing with tail_call
* emit two extra insns:
* if (index >= max_entries) goto out;
* index &= array->index_mask;
* to avoid out-of-bounds cpu speculation
*/
- map_ptr = env->insn_aux_data[i + delta].map_ptr;
- if (map_ptr == BPF_MAP_PTR_POISON) {
+ if (bpf_map_ptr_poisoned(aux)) {
verbose(env, "tail_call abusing map_ptr\n");
return -EINVAL;
}
- if (!map_ptr->unpriv_array)
- continue;
+
+ map_ptr = BPF_MAP_PTR(aux->map_state);
insn_buf[0] = BPF_JMP_IMM(BPF_JGE, BPF_REG_3,
map_ptr->max_entries, 2);
insn_buf[1] = BPF_ALU32_IMM(BPF_AND, BPF_REG_3,
@@ -5527,9 +5566,12 @@ static int fixup_bpf_calls(struct bpf_verifier_env *env)
*/
if (prog->jit_requested && BITS_PER_LONG == 64 &&
insn->imm == BPF_FUNC_map_lookup_elem) {
- map_ptr = env->insn_aux_data[i + delta].map_ptr;
- if (map_ptr == BPF_MAP_PTR_POISON ||
- !map_ptr->ops->map_gen_lookup)
+ aux = &env->insn_aux_data[i + delta];
+ if (bpf_map_ptr_poisoned(aux))
+ goto patch_call_imm;
+
+ map_ptr = BPF_MAP_PTR(aux->map_state);
+ if (!map_ptr->ops->map_gen_lookup)
goto patch_call_imm;
cnt = map_ptr->ops->map_gen_lookup(map_ptr, insn_buf);
diff --git a/tools/testing/selftests/bpf/config b/tools/testing/selftests/bpf/config
index 983dd25d49f4..1eefe211a4a8 100644
--- a/tools/testing/selftests/bpf/config
+++ b/tools/testing/selftests/bpf/config
@@ -5,3 +5,5 @@ CONFIG_BPF_EVENTS=y
CONFIG_TEST_BPF=m
CONFIG_CGROUP_BPF=y
CONFIG_NETDEVSIM=m
+CONFIG_NET_CLS_ACT=y
+CONFIG_NET_SCH_INGRESS=y
diff --git a/tools/testing/selftests/net/reuseport_bpf_numa.c b/tools/testing/selftests/net/reuseport_bpf_numa.c
index 365c32e84189..c9f478b40996 100644
--- a/tools/testing/selftests/net/reuseport_bpf_numa.c
+++ b/tools/testing/selftests/net/reuseport_bpf_numa.c
@@ -23,6 +23,8 @@
#include <unistd.h>
#include <numa.h>
+#include "../kselftest.h"
+
static const int PORT = 8888;
static void build_rcv_group(int *rcv_fd, size_t len, int family, int proto)
@@ -229,7 +231,7 @@ int main(void)
int *rcv_fd, nodes;
if (numa_available() < 0)
- error(1, errno, "no numa api support");
+ ksft_exit_skip("no numa api support\n");
nodes = numa_max_node() + 1;