Commit 68cca81f authored by Eduard Zingerman's avatar Eduard Zingerman Committed by Alexei Starovoitov
Browse files

selftests/bpf: tests for __arg_untrusted void * global func params 



Check usage of __arg_untrusted parameters of primitive type:
- passing of {trusted, untrusted, map value, scalar value, values with
  variable offset} to untrusted `void *`, `char *` or enum is ok;
- varifier represents such parameters as rdonly_untrusted_mem(sz=0).

Acked-by: default avatarKumar Kartikeya Dwivedi <memxor@gmail.com>
Signed-off-by: default avatarEduard Zingerman <eddyz87@gmail.com>
Link: https://lore.kernel.org/r/20250704230354.1323244-9-eddyz87@gmail.com


Signed-off-by: default avatarAlexei Starovoitov <ast@kernel.org>
parent c4aa454c

tools/testing/selftests/bpf/progs/verifier_global_ptr_args.c

+53 −0
Original line number Diff line number Diff line
@@ -260,4 +260,57 @@ int untrusted_to_trusted(void *ctx) 
	return subprog_untrusted2(bpf_get_current_task_btf());

}



__weak int subprog_void_untrusted(void *p __arg_untrusted)

{

	return *(int *)p;

}



__weak int subprog_char_untrusted(char *p __arg_untrusted)

{

	return *(int *)p;

}



__weak int subprog_enum_untrusted(enum bpf_attach_type *p __arg_untrusted)

{

	return *(int *)p;

}



__weak int subprog_enum64_untrusted(enum scx_public_consts *p __arg_untrusted)

{

	return *(int *)p;

}



SEC("tp_btf/sys_enter")

__success

__log_level(2)

__msg("r1 = {{.*}}; {{.*}}R1_w=trusted_ptr_task_struct()")

__msg("Func#1 ('subprog_void_untrusted') is global and assumed valid.")

__msg("Validating subprog_void_untrusted() func#1...")

__msg(": R1=rdonly_untrusted_mem(sz=0)")

int trusted_to_untrusted_mem(void *ctx)

{

	return subprog_void_untrusted(bpf_get_current_task_btf());

}



SEC("tp_btf/sys_enter")

__success

int anything_to_untrusted_mem(void *ctx)

{

	/* untrusted to untrusted mem */

	subprog_void_untrusted(bpf_core_cast(0, struct task_struct));

	/* map value to untrusted mem */

	subprog_void_untrusted(mem);

	/* scalar to untrusted mem */

	subprog_void_untrusted(0);

	/* variable offset to untrusted mem (map) */

	subprog_void_untrusted((void *)mem + off);

	/* variable offset to untrusted mem (trusted) */

	subprog_void_untrusted(bpf_get_current_task_btf() + off);

	/* variable offset to untrusted char/enum/enum64 (map) */

	subprog_char_untrusted(mem + off);

	subprog_enum_untrusted((void *)mem + off);

	subprog_enum64_untrusted((void *)mem + off);

	return 0;

}



char _license[] SEC("license") = "GPL";