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Diffstat (limited to 'kernel/bpf/verifier.c')
-rw-r--r--kernel/bpf/verifier.c182
1 files changed, 138 insertions, 44 deletions
diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c
index 6200519582a6..fb2943ea715d 100644
--- a/kernel/bpf/verifier.c
+++ b/kernel/bpf/verifier.c
@@ -2739,7 +2739,9 @@ static int check_packet_access(struct bpf_verifier_env *env, u32 regno, int off,
regno);
return -EACCES;
}
- err = __check_mem_access(env, regno, off, size, reg->range,
+
+ err = reg->range < 0 ? -EINVAL :
+ __check_mem_access(env, regno, off, size, reg->range,
zero_size_allowed);
if (err) {
verbose(env, "R%d offset is outside of the packet\n", regno);
@@ -4469,6 +4471,11 @@ static int check_map_func_compatibility(struct bpf_verifier_env *env,
func_id != BPF_FUNC_inode_storage_delete)
goto error;
break;
+ case BPF_MAP_TYPE_TASK_STORAGE:
+ if (func_id != BPF_FUNC_task_storage_get &&
+ func_id != BPF_FUNC_task_storage_delete)
+ goto error;
+ break;
default:
break;
}
@@ -4547,6 +4554,11 @@ static int check_map_func_compatibility(struct bpf_verifier_env *env,
if (map->map_type != BPF_MAP_TYPE_INODE_STORAGE)
goto error;
break;
+ case BPF_FUNC_task_storage_get:
+ case BPF_FUNC_task_storage_delete:
+ if (map->map_type != BPF_MAP_TYPE_TASK_STORAGE)
+ goto error;
+ break;
default:
break;
}
@@ -4687,6 +4699,32 @@ static void clear_all_pkt_pointers(struct bpf_verifier_env *env)
__clear_all_pkt_pointers(env, vstate->frame[i]);
}
+enum {
+ AT_PKT_END = -1,
+ BEYOND_PKT_END = -2,
+};
+
+static void mark_pkt_end(struct bpf_verifier_state *vstate, int regn, bool range_open)
+{
+ struct bpf_func_state *state = vstate->frame[vstate->curframe];
+ struct bpf_reg_state *reg = &state->regs[regn];
+
+ if (reg->type != PTR_TO_PACKET)
+ /* PTR_TO_PACKET_META is not supported yet */
+ return;
+
+ /* The 'reg' is pkt > pkt_end or pkt >= pkt_end.
+ * How far beyond pkt_end it goes is unknown.
+ * if (!range_open) it's the case of pkt >= pkt_end
+ * if (range_open) it's the case of pkt > pkt_end
+ * hence this pointer is at least 1 byte bigger than pkt_end
+ */
+ if (range_open)
+ reg->range = BEYOND_PKT_END;
+ else
+ reg->range = AT_PKT_END;
+}
+
static void release_reg_references(struct bpf_verifier_env *env,
struct bpf_func_state *state,
int ref_obj_id)
@@ -5176,11 +5214,14 @@ static int check_helper_call(struct bpf_verifier_env *env, int func_id, int insn
PTR_TO_BTF_ID : PTR_TO_BTF_ID_OR_NULL;
regs[BPF_REG_0].btf_id = meta.ret_btf_id;
}
- } else if (fn->ret_type == RET_PTR_TO_BTF_ID_OR_NULL) {
+ } else if (fn->ret_type == RET_PTR_TO_BTF_ID_OR_NULL ||
+ fn->ret_type == RET_PTR_TO_BTF_ID) {
int ret_btf_id;
mark_reg_known_zero(env, regs, BPF_REG_0);
- regs[BPF_REG_0].type = PTR_TO_BTF_ID_OR_NULL;
+ regs[BPF_REG_0].type = fn->ret_type == RET_PTR_TO_BTF_ID ?
+ PTR_TO_BTF_ID :
+ PTR_TO_BTF_ID_OR_NULL;
ret_btf_id = *fn->ret_btf_id;
if (ret_btf_id == 0) {
verbose(env, "invalid return type %d of func %s#%d\n",
@@ -6695,7 +6736,7 @@ static int check_alu_op(struct bpf_verifier_env *env, struct bpf_insn *insn)
static void __find_good_pkt_pointers(struct bpf_func_state *state,
struct bpf_reg_state *dst_reg,
- enum bpf_reg_type type, u16 new_range)
+ enum bpf_reg_type type, int new_range)
{
struct bpf_reg_state *reg;
int i;
@@ -6720,8 +6761,7 @@ static void find_good_pkt_pointers(struct bpf_verifier_state *vstate,
enum bpf_reg_type type,
bool range_right_open)
{
- u16 new_range;
- int i;
+ int new_range, i;
if (dst_reg->off < 0 ||
(dst_reg->off == 0 && range_right_open))
@@ -6972,6 +7012,67 @@ static int is_branch_taken(struct bpf_reg_state *reg, u64 val, u8 opcode,
return is_branch64_taken(reg, val, opcode);
}
+static int flip_opcode(u32 opcode)
+{
+ /* How can we transform "a <op> b" into "b <op> a"? */
+ static const u8 opcode_flip[16] = {
+ /* these stay the same */
+ [BPF_JEQ >> 4] = BPF_JEQ,
+ [BPF_JNE >> 4] = BPF_JNE,
+ [BPF_JSET >> 4] = BPF_JSET,
+ /* these swap "lesser" and "greater" (L and G in the opcodes) */
+ [BPF_JGE >> 4] = BPF_JLE,
+ [BPF_JGT >> 4] = BPF_JLT,
+ [BPF_JLE >> 4] = BPF_JGE,
+ [BPF_JLT >> 4] = BPF_JGT,
+ [BPF_JSGE >> 4] = BPF_JSLE,
+ [BPF_JSGT >> 4] = BPF_JSLT,
+ [BPF_JSLE >> 4] = BPF_JSGE,
+ [BPF_JSLT >> 4] = BPF_JSGT
+ };
+ return opcode_flip[opcode >> 4];
+}
+
+static int is_pkt_ptr_branch_taken(struct bpf_reg_state *dst_reg,
+ struct bpf_reg_state *src_reg,
+ u8 opcode)
+{
+ struct bpf_reg_state *pkt;
+
+ if (src_reg->type == PTR_TO_PACKET_END) {
+ pkt = dst_reg;
+ } else if (dst_reg->type == PTR_TO_PACKET_END) {
+ pkt = src_reg;
+ opcode = flip_opcode(opcode);
+ } else {
+ return -1;
+ }
+
+ if (pkt->range >= 0)
+ return -1;
+
+ switch (opcode) {
+ case BPF_JLE:
+ /* pkt <= pkt_end */
+ fallthrough;
+ case BPF_JGT:
+ /* pkt > pkt_end */
+ if (pkt->range == BEYOND_PKT_END)
+ /* pkt has at last one extra byte beyond pkt_end */
+ return opcode == BPF_JGT;
+ break;
+ case BPF_JLT:
+ /* pkt < pkt_end */
+ fallthrough;
+ case BPF_JGE:
+ /* pkt >= pkt_end */
+ if (pkt->range == BEYOND_PKT_END || pkt->range == AT_PKT_END)
+ return opcode == BPF_JGE;
+ break;
+ }
+ return -1;
+}
+
/* Adjusts the register min/max values in the case that the dst_reg is the
* variable register that we are working on, and src_reg is a constant or we're
* simply doing a BPF_K check.
@@ -7135,23 +7236,7 @@ static void reg_set_min_max_inv(struct bpf_reg_state *true_reg,
u64 val, u32 val32,
u8 opcode, bool is_jmp32)
{
- /* How can we transform "a <op> b" into "b <op> a"? */
- static const u8 opcode_flip[16] = {
- /* these stay the same */
- [BPF_JEQ >> 4] = BPF_JEQ,
- [BPF_JNE >> 4] = BPF_JNE,
- [BPF_JSET >> 4] = BPF_JSET,
- /* these swap "lesser" and "greater" (L and G in the opcodes) */
- [BPF_JGE >> 4] = BPF_JLE,
- [BPF_JGT >> 4] = BPF_JLT,
- [BPF_JLE >> 4] = BPF_JGE,
- [BPF_JLT >> 4] = BPF_JGT,
- [BPF_JSGE >> 4] = BPF_JSLE,
- [BPF_JSGT >> 4] = BPF_JSLT,
- [BPF_JSLE >> 4] = BPF_JSGE,
- [BPF_JSLT >> 4] = BPF_JSGT
- };
- opcode = opcode_flip[opcode >> 4];
+ opcode = flip_opcode(opcode);
/* This uses zero as "not present in table"; luckily the zero opcode,
* BPF_JA, can't get here.
*/
@@ -7333,6 +7418,7 @@ static bool try_match_pkt_pointers(const struct bpf_insn *insn,
/* pkt_data' > pkt_end, pkt_meta' > pkt_data */
find_good_pkt_pointers(this_branch, dst_reg,
dst_reg->type, false);
+ mark_pkt_end(other_branch, insn->dst_reg, true);
} else if ((dst_reg->type == PTR_TO_PACKET_END &&
src_reg->type == PTR_TO_PACKET) ||
(reg_is_init_pkt_pointer(dst_reg, PTR_TO_PACKET) &&
@@ -7340,6 +7426,7 @@ static bool try_match_pkt_pointers(const struct bpf_insn *insn,
/* pkt_end > pkt_data', pkt_data > pkt_meta' */
find_good_pkt_pointers(other_branch, src_reg,
src_reg->type, true);
+ mark_pkt_end(this_branch, insn->src_reg, false);
} else {
return false;
}
@@ -7352,6 +7439,7 @@ static bool try_match_pkt_pointers(const struct bpf_insn *insn,
/* pkt_data' < pkt_end, pkt_meta' < pkt_data */
find_good_pkt_pointers(other_branch, dst_reg,
dst_reg->type, true);
+ mark_pkt_end(this_branch, insn->dst_reg, false);
} else if ((dst_reg->type == PTR_TO_PACKET_END &&
src_reg->type == PTR_TO_PACKET) ||
(reg_is_init_pkt_pointer(dst_reg, PTR_TO_PACKET) &&
@@ -7359,6 +7447,7 @@ static bool try_match_pkt_pointers(const struct bpf_insn *insn,
/* pkt_end < pkt_data', pkt_data > pkt_meta' */
find_good_pkt_pointers(this_branch, src_reg,
src_reg->type, false);
+ mark_pkt_end(other_branch, insn->src_reg, true);
} else {
return false;
}
@@ -7371,6 +7460,7 @@ static bool try_match_pkt_pointers(const struct bpf_insn *insn,
/* pkt_data' >= pkt_end, pkt_meta' >= pkt_data */
find_good_pkt_pointers(this_branch, dst_reg,
dst_reg->type, true);
+ mark_pkt_end(other_branch, insn->dst_reg, false);
} else if ((dst_reg->type == PTR_TO_PACKET_END &&
src_reg->type == PTR_TO_PACKET) ||
(reg_is_init_pkt_pointer(dst_reg, PTR_TO_PACKET) &&
@@ -7378,6 +7468,7 @@ static bool try_match_pkt_pointers(const struct bpf_insn *insn,
/* pkt_end >= pkt_data', pkt_data >= pkt_meta' */
find_good_pkt_pointers(other_branch, src_reg,
src_reg->type, false);
+ mark_pkt_end(this_branch, insn->src_reg, true);
} else {
return false;
}
@@ -7390,6 +7481,7 @@ static bool try_match_pkt_pointers(const struct bpf_insn *insn,
/* pkt_data' <= pkt_end, pkt_meta' <= pkt_data */
find_good_pkt_pointers(other_branch, dst_reg,
dst_reg->type, false);
+ mark_pkt_end(this_branch, insn->dst_reg, true);
} else if ((dst_reg->type == PTR_TO_PACKET_END &&
src_reg->type == PTR_TO_PACKET) ||
(reg_is_init_pkt_pointer(dst_reg, PTR_TO_PACKET) &&
@@ -7397,6 +7489,7 @@ static bool try_match_pkt_pointers(const struct bpf_insn *insn,
/* pkt_end <= pkt_data', pkt_data <= pkt_meta' */
find_good_pkt_pointers(this_branch, src_reg,
src_reg->type, true);
+ mark_pkt_end(other_branch, insn->src_reg, false);
} else {
return false;
}
@@ -7496,6 +7589,10 @@ static int check_cond_jmp_op(struct bpf_verifier_env *env,
src_reg->var_off.value,
opcode,
is_jmp32);
+ } else if (reg_is_pkt_pointer_any(dst_reg) &&
+ reg_is_pkt_pointer_any(src_reg) &&
+ !is_jmp32) {
+ pred = is_pkt_ptr_branch_taken(dst_reg, src_reg, opcode);
}
if (pred >= 0) {
@@ -7504,7 +7601,8 @@ static int check_cond_jmp_op(struct bpf_verifier_env *env,
*/
if (!__is_pointer_value(false, dst_reg))
err = mark_chain_precision(env, insn->dst_reg);
- if (BPF_SRC(insn->code) == BPF_X && !err)
+ if (BPF_SRC(insn->code) == BPF_X && !err &&
+ !__is_pointer_value(false, src_reg))
err = mark_chain_precision(env, insn->src_reg);
if (err)
return err;
@@ -9719,11 +9817,21 @@ static int check_map_prog_compatibility(struct bpf_verifier_env *env,
verbose(env, "trace type programs with run-time allocated hash maps are unsafe. Switch to preallocated hash maps.\n");
}
- if ((is_tracing_prog_type(prog_type) ||
- prog_type == BPF_PROG_TYPE_SOCKET_FILTER) &&
- map_value_has_spin_lock(map)) {
- verbose(env, "tracing progs cannot use bpf_spin_lock yet\n");
- return -EINVAL;
+ if (map_value_has_spin_lock(map)) {
+ if (prog_type == BPF_PROG_TYPE_SOCKET_FILTER) {
+ verbose(env, "socket filter progs cannot use bpf_spin_lock yet\n");
+ return -EINVAL;
+ }
+
+ if (is_tracing_prog_type(prog_type)) {
+ verbose(env, "tracing progs cannot use bpf_spin_lock yet\n");
+ return -EINVAL;
+ }
+
+ if (prog->aux->sleepable) {
+ verbose(env, "sleepable progs cannot use bpf_spin_lock yet\n");
+ return -EINVAL;
+ }
}
if ((bpf_prog_is_dev_bound(prog->aux) || bpf_map_is_dev_bound(map)) &&
@@ -11454,20 +11562,6 @@ static int check_attach_modify_return(unsigned long addr, const char *func_name)
return -EINVAL;
}
-/* non exhaustive list of sleepable bpf_lsm_*() functions */
-BTF_SET_START(btf_sleepable_lsm_hooks)
-#ifdef CONFIG_BPF_LSM
-BTF_ID(func, bpf_lsm_bprm_committed_creds)
-#else
-BTF_ID_UNUSED
-#endif
-BTF_SET_END(btf_sleepable_lsm_hooks)
-
-static int check_sleepable_lsm_hook(u32 btf_id)
-{
- return btf_id_set_contains(&btf_sleepable_lsm_hooks, btf_id);
-}
-
/* list of non-sleepable functions that are otherwise on
* ALLOW_ERROR_INJECTION list
*/
@@ -11689,7 +11783,7 @@ int bpf_check_attach_target(struct bpf_verifier_log *log,
/* LSM progs check that they are attached to bpf_lsm_*() funcs.
* Only some of them are sleepable.
*/
- if (check_sleepable_lsm_hook(btf_id))
+ if (bpf_lsm_is_sleepable_hook(btf_id))
ret = 0;
break;
default:
generated by cgit v1.2.3 (git 2.25.1) at 2024-12-04 07:29:54 +0000