Commit 59bb14bd authored by Jakub Kicinski's avatar Jakub Kicinski
Browse files

Merge tag 'for-netdev' of https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf 

Daniel Borkmann says:

====================
pull-request: bpf 2023-06-21

We've added 7 non-merge commits during the last 14 day(s) which contain
a total of 7 files changed, 181 insertions(+), 15 deletions(-).

The main changes are:

1) Fix a verifier id tracking issue with scalars upon spill,
   from Maxim Mikityanskiy.

2) Fix NULL dereference if an exception is generated while a BPF
   subprogram is running, from Krister Johansen.

3) Fix a BTF verification failure when compiling kernel with LLVM_IAS=0,
   from Florent Revest.

4) Fix expected_attach_type enforcement for kprobe_multi link,
   from Jiri Olsa.

5) Fix a bpf_jit_dump issue for x86_64 to pick the correct JITed image,
   from Yonghong Song.

* tag 'for-netdev' of https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf:
  bpf: Force kprobe multi expected_attach_type for kprobe_multi link
  bpf/btf: Accept function names that contain dots
  selftests/bpf: add a test for subprogram extables
  bpf: ensure main program has an extable
  bpf: Fix a bpf_jit_dump issue for x86_64 with sysctl bpf_jit_enable.
  selftests/bpf: Add test cases to assert proper ID tracking on spill
  bpf: Fix verifier id tracking of scalars on spill
====================

Link: https://lore.kernel.org/r/20230621101116.16122-1-daniel@iogearbox.net


Signed-off-by: default avatarJakub Kicinski <kuba@kernel.org>
parents a129b41f db8eae6b

arch/x86/net/bpf_jit_comp.c

+1 −1
Original line number Diff line number Diff line
@@ -2570,7 +2570,7 @@ struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog) 
	}



	if (bpf_jit_enable > 1)

		bpf_jit_dump(prog->len, proglen, pass + 1, image);

		bpf_jit_dump(prog->len, proglen, pass + 1, rw_image);



	if (image) {

		if (!prog->is_func || extra_pass) {

kernel/bpf/btf.c

+8 −12
Original line number Diff line number Diff line
@@ -744,13 +744,12 @@ static bool btf_name_offset_valid(const struct btf *btf, u32 offset) 
	return offset < btf->hdr.str_len;

}



static bool __btf_name_char_ok(char c, bool first, bool dot_ok)

static bool __btf_name_char_ok(char c, bool first)

{

	if ((first ? !isalpha(c) :

		     !isalnum(c)) &&

	    c != '_' &&

	    ((c == '.' && !dot_ok) ||

	      c != '.'))

	    c != '.')

		return false;

	return true;

}
@@ -767,20 +766,20 @@ static const char *btf_str_by_offset(const struct btf *btf, u32 offset) 
	return NULL;

}



static bool __btf_name_valid(const struct btf *btf, u32 offset, bool dot_ok)

static bool __btf_name_valid(const struct btf *btf, u32 offset)

{

	/* offset must be valid */

	const char *src = btf_str_by_offset(btf, offset);

	const char *src_limit;



	if (!__btf_name_char_ok(*src, true, dot_ok))

	if (!__btf_name_char_ok(*src, true))

		return false;



	/* set a limit on identifier length */

	src_limit = src + KSYM_NAME_LEN;

	src++;

	while (*src && src < src_limit) {

		if (!__btf_name_char_ok(*src, false, dot_ok))

		if (!__btf_name_char_ok(*src, false))

			return false;

		src++;

	}
@@ -788,17 +787,14 @@ static bool __btf_name_valid(const struct btf *btf, u32 offset, bool dot_ok) 
	return !*src;

}



/* Only C-style identifier is permitted. This can be relaxed if

 * necessary.

 */

static bool btf_name_valid_identifier(const struct btf *btf, u32 offset)

{

	return __btf_name_valid(btf, offset, false);

	return __btf_name_valid(btf, offset);

}



static bool btf_name_valid_section(const struct btf *btf, u32 offset)

{

	return __btf_name_valid(btf, offset, true);

	return __btf_name_valid(btf, offset);

}



static const char *__btf_name_by_offset(const struct btf *btf, u32 offset)
@@ -4422,7 +4418,7 @@ static s32 btf_var_check_meta(struct btf_verifier_env *env, 
	}



	if (!t->name_off ||

	    !__btf_name_valid(env->btf, t->name_off, true)) {

	    !__btf_name_valid(env->btf, t->name_off)) {

		btf_verifier_log_type(env, t, "Invalid name");

		return -EINVAL;

	}

kernel/bpf/syscall.c

+5 −0
Original line number Diff line number Diff line
@@ -3440,6 +3440,11 @@ static int bpf_prog_attach_check_attach_type(const struct bpf_prog *prog, 
		return prog->enforce_expected_attach_type &&

			prog->expected_attach_type != attach_type ?

			-EINVAL : 0;

	case BPF_PROG_TYPE_KPROBE:

		if (prog->expected_attach_type == BPF_TRACE_KPROBE_MULTI &&

		    attach_type != BPF_TRACE_KPROBE_MULTI)

			return -EINVAL;

		return 0;

	default:

		return 0;

	}

kernel/bpf/verifier.c

+8 −2
Original line number Diff line number Diff line
@@ -3868,6 +3868,9 @@ static int check_stack_write_fixed_off(struct bpf_verifier_env *env, 
				return err;

		}

		save_register_state(state, spi, reg, size);

		/* Break the relation on a narrowing spill. */

		if (fls64(reg->umax_value) > BITS_PER_BYTE * size)

			state->stack[spi].spilled_ptr.id = 0;

	} else if (!reg && !(off % BPF_REG_SIZE) && is_bpf_st_mem(insn) &&

		   insn->imm != 0 && env->bpf_capable) {

		struct bpf_reg_state fake_reg = {};
@@ -17214,9 +17217,10 @@ static int jit_subprogs(struct bpf_verifier_env *env) 
	}









	/* finally lock prog and jit images for all functions and









	 * populate kallsysm









	 * populate kallsysm. Begin at the first subprogram, since









	 * bpf_prog_load will add the kallsyms for the main program.









	 */









	for (i = 0; i < env->subprog_cnt; i++) {









	for (i = 1; i < env->subprog_cnt; i++) {









		bpf_prog_lock_ro(func[i]);









		bpf_prog_kallsyms_add(func[i]);









	}








@@ -17242,6 +17246,8 @@ static int jit_subprogs(struct bpf_verifier_env *env)







	prog->jited = 1;









	prog->bpf_func = func[0]->bpf_func;









	prog->jited_len = func[0]->jited_len;









	prog->aux->extable = func[0]->aux->extable;









	prog->aux->num_exentries = func[0]->aux->num_exentries;









	prog->aux->func = func;









	prog->aux->func_cnt = env->subprog_cnt;









	bpf_prog_jit_attempt_done(prog);
































tools/testing/selftests/bpf/prog_tests/subprogs_extable.c
0 → 100644



+29
−0






























Original line number
Diff line number
Diff line









// SPDX-License-Identifier: GPL-2.0



















#include <test_progs.h>









#include "test_subprogs_extable.skel.h"



















void test_subprogs_extable(void)









{









	const int read_sz = 456;









	struct test_subprogs_extable *skel;









	int err;



















	skel = test_subprogs_extable__open_and_load();









	if (!ASSERT_OK_PTR(skel, "skel_open_and_load"))









		return;



















	err = test_subprogs_extable__attach(skel);









	if (!ASSERT_OK(err, "skel_attach"))









		goto cleanup;



















	/* trigger tracepoint */









	ASSERT_OK(trigger_module_test_read(read_sz), "trigger_read");



















	ASSERT_NEQ(skel->bss->triggered, 0, "verify at least one program ran");



















	test_subprogs_extable__detach(skel);



















cleanup:









	test_subprogs_extable__destroy(skel);









}