Commit 449f08fa authored by Alexei Starovoitov's avatar Alexei Starovoitov
Browse files

bpf: Move fixup/post-processing logic from verifier.c into fixups.c 



verifier.c is huge. Split fixup/post-processing logic that runs after
the verifier accepted the program into fixups.c.

Mechanical move. No functional changes.

Acked-by: default avatarKumar Kartikeya Dwivedi <memxor@gmail.com>
Acked-by: default avatarDaniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/r/20260412152936.54262-2-alexei.starovoitov@gmail.com


Signed-off-by: default avatarAlexei Starovoitov <ast@kernel.org>
parent 2ec74a05

include/linux/bpf_verifier.h

+78 −0
Original line number Diff line number Diff line
@@ -1205,4 +1205,82 @@ void bpf_stack_liveness_free(struct bpf_verifier_env *env); 
int bpf_live_stack_query_init(struct bpf_verifier_env *env, struct bpf_verifier_state *st);

bool bpf_stack_slot_alive(struct bpf_verifier_env *env, u32 frameno, u32 spi);



#define BPF_MAP_KEY_POISON	(1ULL << 63)

#define BPF_MAP_KEY_SEEN	(1ULL << 62)



static inline bool bpf_map_ptr_poisoned(const struct bpf_insn_aux_data *aux)

{

	return aux->map_ptr_state.poison;

}



static inline bool bpf_map_ptr_unpriv(const struct bpf_insn_aux_data *aux)

{

	return aux->map_ptr_state.unpriv;

}



static inline bool bpf_map_key_poisoned(const struct bpf_insn_aux_data *aux)

{

	return aux->map_key_state & BPF_MAP_KEY_POISON;

}



static inline bool bpf_map_key_unseen(const struct bpf_insn_aux_data *aux)

{

	return !(aux->map_key_state & BPF_MAP_KEY_SEEN);

}



static inline u64 bpf_map_key_immediate(const struct bpf_insn_aux_data *aux)

{

	return aux->map_key_state & ~(BPF_MAP_KEY_SEEN | BPF_MAP_KEY_POISON);

}



#define MAX_PACKET_OFF 0xffff



enum bpf_reg_arg_type {

	SRC_OP,		/* register is used as source operand */

	DST_OP,		/* register is used as destination operand */

	DST_OP_NO_MARK	/* same as above, check only, don't mark */

};



#define MAX_KFUNC_DESCS 256



struct bpf_kfunc_desc {

	struct btf_func_model func_model;

	u32 func_id;

	s32 imm;

	u16 offset;

	unsigned long addr;

};



struct bpf_kfunc_desc_tab {

	/* Sorted by func_id (BTF ID) and offset (fd_array offset) during

	 * verification. JITs do lookups by bpf_insn, where func_id may not be

	 * available, therefore at the end of verification do_misc_fixups()

	 * sorts this by imm and offset.

	 */

	struct bpf_kfunc_desc descs[MAX_KFUNC_DESCS];

	u32 nr_descs;

};



/* Functions exported from verifier.c, used by fixups.c */

bool bpf_is_reg64(struct bpf_insn *insn, u32 regno, struct bpf_reg_state *reg, enum bpf_reg_arg_type t);

void bpf_clear_insn_aux_data(struct bpf_verifier_env *env, int start, int len);

void bpf_mark_subprog_exc_cb(struct bpf_verifier_env *env, int subprog);

bool bpf_allow_tail_call_in_subprogs(struct bpf_verifier_env *env);

bool bpf_verifier_inlines_helper_call(struct bpf_verifier_env *env, s32 imm);

int bpf_add_kfunc_call(struct bpf_verifier_env *env, u32 func_id, u16 offset);

int bpf_fixup_kfunc_call(struct bpf_verifier_env *env, struct bpf_insn *insn,

			 struct bpf_insn *insn_buf, int insn_idx, int *cnt);



/* Functions in fixups.c, called from bpf_check() */

int bpf_remove_fastcall_spills_fills(struct bpf_verifier_env *env);

int bpf_optimize_bpf_loop(struct bpf_verifier_env *env);

void bpf_opt_hard_wire_dead_code_branches(struct bpf_verifier_env *env);

int bpf_opt_remove_dead_code(struct bpf_verifier_env *env);

int bpf_opt_remove_nops(struct bpf_verifier_env *env);

int bpf_opt_subreg_zext_lo32_rnd_hi32(struct bpf_verifier_env *env, const union bpf_attr *attr);

int bpf_convert_ctx_accesses(struct bpf_verifier_env *env);

int bpf_jit_subprogs(struct bpf_verifier_env *env);

int bpf_fixup_call_args(struct bpf_verifier_env *env);

int bpf_do_misc_fixups(struct bpf_verifier_env *env);



#endif /* _LINUX_BPF_VERIFIER_H */

kernel/bpf/Makefile

+1 −0
Original line number Diff line number Diff line
@@ -11,6 +11,7 @@ obj-$(CONFIG_BPF_SYSCALL) += bpf_iter.o map_iter.o task_iter.o prog_iter.o link_ 
obj-$(CONFIG_BPF_SYSCALL) += hashtab.o arraymap.o percpu_freelist.o bpf_lru_list.o lpm_trie.o map_in_map.o bloom_filter.o

obj-$(CONFIG_BPF_SYSCALL) += local_storage.o queue_stack_maps.o ringbuf.o bpf_insn_array.o

obj-$(CONFIG_BPF_SYSCALL) += bpf_local_storage.o bpf_task_storage.o

obj-$(CONFIG_BPF_SYSCALL) += fixups.o

obj-${CONFIG_BPF_LSM}	  += bpf_inode_storage.o

obj-$(CONFIG_BPF_SYSCALL) += disasm.o mprog.o

obj-$(CONFIG_BPF_JIT) += trampoline.o

kernel/bpf/fixups.c

0 → 100644
+2457 −0

File added.

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kernel/bpf/verifier.c

+230 −2725

File changed.

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