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Diffstat (limited to 'include/linux/bpf_verifier.h')
-rw-r--r--include/linux/bpf_verifier.h27
1 files changed, 24 insertions, 3 deletions
diff --git a/include/linux/bpf_verifier.h b/include/linux/bpf_verifier.h
index c1fc4af47f69..e8439f6cbe57 100644
--- a/include/linux/bpf_verifier.h
+++ b/include/linux/bpf_verifier.h
@@ -72,6 +72,18 @@ struct bpf_reg_state {
u32 mem_size; /* for PTR_TO_MEM | PTR_TO_MEM_OR_NULL */
+ /* For dynptr stack slots */
+ struct {
+ enum bpf_dynptr_type type;
+ /* A dynptr is 16 bytes so it takes up 2 stack slots.
+ * We need to track which slot is the first slot
+ * to protect against cases where the user may try to
+ * pass in an address starting at the second slot of the
+ * dynptr.
+ */
+ bool first_slot;
+ } dynptr;
+
/* Max size from any of the above. */
struct {
unsigned long raw1;
@@ -88,6 +100,8 @@ struct bpf_reg_state {
* for the purpose of tracking that it's freed.
* For PTR_TO_SOCKET this is used to share which pointers retain the
* same reference to the socket, to determine proper reference freeing.
+ * For stack slots that are dynptrs, this is used to track references to
+ * the dynptr to determine proper reference freeing.
*/
u32 id;
/* PTR_TO_SOCKET and PTR_TO_TCP_SOCK could be a ptr returned
@@ -174,9 +188,15 @@ enum bpf_stack_slot_type {
STACK_SPILL, /* register spilled into stack */
STACK_MISC, /* BPF program wrote some data into this slot */
STACK_ZERO, /* BPF program wrote constant zero */
+ /* A dynptr is stored in this stack slot. The type of dynptr
+ * is stored in bpf_stack_state->spilled_ptr.dynptr.type
+ */
+ STACK_DYNPTR,
};
#define BPF_REG_SIZE 8 /* size of eBPF register in bytes */
+#define BPF_DYNPTR_SIZE sizeof(struct bpf_dynptr_kern)
+#define BPF_DYNPTR_NR_SLOTS (BPF_DYNPTR_SIZE / BPF_REG_SIZE)
struct bpf_stack_state {
struct bpf_reg_state spilled_ptr;
@@ -523,8 +543,7 @@ int check_ptr_off_reg(struct bpf_verifier_env *env,
const struct bpf_reg_state *reg, int regno);
int check_func_arg_reg_off(struct bpf_verifier_env *env,
const struct bpf_reg_state *reg, int regno,
- enum bpf_arg_type arg_type,
- bool is_release_func);
+ enum bpf_arg_type arg_type);
int check_kfunc_mem_size_reg(struct bpf_verifier_env *env, struct bpf_reg_state *reg,
u32 regno);
int check_mem_reg(struct bpf_verifier_env *env, struct bpf_reg_state *reg,
@@ -570,9 +589,11 @@ static inline u32 type_flag(u32 type)
return type & ~BPF_BASE_TYPE_MASK;
}
+/* only use after check_attach_btf_id() */
static inline enum bpf_prog_type resolve_prog_type(struct bpf_prog *prog)
{
- return prog->aux->dst_prog ? prog->aux->dst_prog->type : prog->type;
+ return prog->type == BPF_PROG_TYPE_EXT ?
+ prog->aux->dst_prog->type : prog->type;
}
#endif /* _LINUX_BPF_VERIFIER_H */