Commit 0a6ea1ce authored by Alexei Starovoitov's avatar Alexei Starovoitov
Browse files

Merge "do not rely on ALLOW_ERROR_INJECTION for fmod_ret" into bpf-next 



Merge commit 5b481aca ("bpf: do not rely on ALLOW_ERROR_INJECTION for fmod_ret")
from hid tree into bpf-next.

Signed-off-by: default avatarAlexei Starovoitov <ast@kernel.org>
parents e9b4aeed 5b481aca

include/linux/btf.h

+2 −0
Original line number Diff line number Diff line
@@ -478,8 +478,10 @@ struct btf *bpf_prog_get_target_btf(const struct bpf_prog *prog); 
u32 *btf_kfunc_id_set_contains(const struct btf *btf,

			       enum bpf_prog_type prog_type,

			       u32 kfunc_btf_id);

u32 *btf_kfunc_is_modify_return(const struct btf *btf, u32 kfunc_btf_id);

int register_btf_kfunc_id_set(enum bpf_prog_type prog_type,

			      const struct btf_kfunc_id_set *s);

int register_btf_fmodret_id_set(const struct btf_kfunc_id_set *kset);

s32 btf_find_dtor_kfunc(struct btf *btf, u32 btf_id);

int register_btf_id_dtor_kfuncs(const struct btf_id_dtor_kfunc *dtors, u32 add_cnt,

				struct module *owner);

kernel/bpf/btf.c

+25 −5
Original line number Diff line number Diff line
@@ -206,6 +206,7 @@ enum btf_kfunc_hook { 
	BTF_KFUNC_HOOK_STRUCT_OPS,

	BTF_KFUNC_HOOK_TRACING,

	BTF_KFUNC_HOOK_SYSCALL,

	BTF_KFUNC_HOOK_FMODRET,

	BTF_KFUNC_HOOK_MAX,

};
@@ -7608,11 +7609,14 @@ u32 *btf_kfunc_id_set_contains(const struct btf *btf, 
	return __btf_kfunc_id_set_contains(btf, hook, kfunc_btf_id);

}



/* This function must be invoked only from initcalls/module init functions */

int register_btf_kfunc_id_set(enum bpf_prog_type prog_type,

u32 *btf_kfunc_is_modify_return(const struct btf *btf, u32 kfunc_btf_id)

{

	return __btf_kfunc_id_set_contains(btf, BTF_KFUNC_HOOK_FMODRET, kfunc_btf_id);

}



static int __register_btf_kfunc_id_set(enum btf_kfunc_hook hook,

				       const struct btf_kfunc_id_set *kset)

{

	enum btf_kfunc_hook hook;

	struct btf *btf;

	int ret;
@@ -7631,13 +7635,29 @@ int register_btf_kfunc_id_set(enum bpf_prog_type prog_type, 
	if (IS_ERR(btf))

		return PTR_ERR(btf);



	hook = bpf_prog_type_to_kfunc_hook(prog_type);

	ret = btf_populate_kfunc_set(btf, hook, kset->set);

	btf_put(btf);

	return ret;

}



/* This function must be invoked only from initcalls/module init functions */

int register_btf_kfunc_id_set(enum bpf_prog_type prog_type,

			      const struct btf_kfunc_id_set *kset)

{

	enum btf_kfunc_hook hook;



	hook = bpf_prog_type_to_kfunc_hook(prog_type);

	return __register_btf_kfunc_id_set(hook, kset);

}

EXPORT_SYMBOL_GPL(register_btf_kfunc_id_set);



/* This function must be invoked only from initcalls/module init functions */

int register_btf_fmodret_id_set(const struct btf_kfunc_id_set *kset)

{

	return __register_btf_kfunc_id_set(BTF_KFUNC_HOOK_FMODRET, kset);

}

EXPORT_SYMBOL_GPL(register_btf_fmodret_id_set);



s32 btf_find_dtor_kfunc(struct btf *btf, u32 btf_id)

{

	struct btf_id_dtor_kfunc_tab *tab = btf->dtor_kfunc_tab;

kernel/bpf/verifier.c

+15 −2
Original line number Diff line number Diff line
@@ -16519,12 +16519,22 @@ int bpf_check_attach_target(struct bpf_verifier_log *log, 
			ret = -EINVAL;

			switch (prog->type) {

			case BPF_PROG_TYPE_TRACING:

				/* fentry/fexit/fmod_ret progs can be sleepable only if they are



				/* fentry/fexit/fmod_ret progs can be sleepable if they are

				 * attached to ALLOW_ERROR_INJECTION and are not in denylist.

				 */

				if (!check_non_sleepable_error_inject(btf_id) &&

				    within_error_injection_list(addr))

					ret = 0;

				/* fentry/fexit/fmod_ret progs can also be sleepable if they are

				 * in the fmodret id set with the KF_SLEEPABLE flag.

				 */

				else {

					u32 *flags = btf_kfunc_is_modify_return(btf, btf_id);



					if (flags && (*flags & KF_SLEEPABLE))

						ret = 0;

				}

				break;

			case BPF_PROG_TYPE_LSM:

				/* LSM progs check that they are attached to bpf_lsm_*() funcs.
@@ -16545,7 +16555,10 @@ int bpf_check_attach_target(struct bpf_verifier_log *log, 
				bpf_log(log, "can't modify return codes of BPF programs\n");

				return -EINVAL;

			}

			ret = check_attach_modify_return(addr, tname);

			ret = -EINVAL;

			if (btf_kfunc_is_modify_return(btf, btf_id) ||

			    !check_attach_modify_return(addr, tname))

				ret = 0;

			if (ret) {

				bpf_log(log, "%s() is not modifiable\n", tname);

				return ret;

net/bpf/test_run.c

+11 −3
Original line number Diff line number Diff line
@@ -489,7 +489,6 @@ int noinline bpf_fentry_test1(int a) 
	return a + 1;

}

EXPORT_SYMBOL_GPL(bpf_fentry_test1);

ALLOW_ERROR_INJECTION(bpf_fentry_test1, ERRNO);



int noinline bpf_fentry_test2(int a, u64 b)

{
@@ -733,7 +732,15 @@ noinline void bpf_kfunc_call_test_destructive(void) 


__diag_pop();



ALLOW_ERROR_INJECTION(bpf_modify_return_test, ERRNO);

BTF_SET8_START(bpf_test_modify_return_ids)

BTF_ID_FLAGS(func, bpf_modify_return_test)

BTF_ID_FLAGS(func, bpf_fentry_test1, KF_SLEEPABLE)

BTF_SET8_END(bpf_test_modify_return_ids)



static const struct btf_kfunc_id_set bpf_test_modify_return_set = {

	.owner = THIS_MODULE,

	.set   = &bpf_test_modify_return_ids,

};



BTF_SET8_START(test_sk_check_kfunc_ids)

BTF_ID_FLAGS(func, bpf_kfunc_call_test1)
@@ -1666,7 +1673,8 @@ static int __init bpf_prog_test_run_init(void) 
	};

	int ret;



	ret = register_btf_kfunc_id_set(BPF_PROG_TYPE_SCHED_CLS, &bpf_prog_test_kfunc_set);

	ret = register_btf_fmodret_id_set(&bpf_test_modify_return_set);

	ret = ret ?: register_btf_kfunc_id_set(BPF_PROG_TYPE_SCHED_CLS, &bpf_prog_test_kfunc_set);

	ret = ret ?: register_btf_kfunc_id_set(BPF_PROG_TYPE_TRACING, &bpf_prog_test_kfunc_set);

	ret = ret ?: register_btf_kfunc_id_set(BPF_PROG_TYPE_SYSCALL, &bpf_prog_test_kfunc_set);

	return ret ?: register_btf_id_dtor_kfuncs(bpf_prog_test_dtor_kfunc,