Merge branch 'bpf-next/master' into bpf-next/for-next

Signed-off-by: Alexei Starovoitov <[email protected]>

Author: Alexei Starovoitov

include/linux/btf.h

@@ -580,6 +580,7 @@ bool btf_is_prog_ctx_type(struct bpf_verifier_log *log, const struct btf *btf,
 int get_kern_ctx_btf_id(struct bpf_verifier_log *log, enum bpf_prog_type prog_type);
 bool btf_types_are_same(const struct btf *btf1, u32 id1,
 			const struct btf *btf2, u32 id2);
+int btf_check_iter_arg(struct btf *btf, const struct btf_type *func, int arg_idx);
 #else
 static inline const struct btf_type *btf_type_by_id(const struct btf *btf,
 						    u32 type_id)
@@ -654,6 +655,10 @@ static inline bool btf_types_are_same(const struct btf *btf1, u32 id1,
 {
 	return false;
 }
+static inline int btf_check_iter_arg(struct btf *btf, const struct btf_type *func, int arg_idx)
+{
+	return -EOPNOTSUPP;
+}
 #endif
 
 static inline bool btf_type_is_struct_ptr(struct btf *btf, const struct btf_type *t)

kernel/bpf/btf.c

@@ -8042,15 +8042,44 @@ BTF_ID_LIST_GLOBAL(btf_tracing_ids, MAX_BTF_TRACING_TYPE)
 BTF_TRACING_TYPE_xxx
 #undef BTF_TRACING_TYPE
 
+/* Validate well-formedness of iter argument type.
+ * On success, return positive BTF ID of iter state's STRUCT type.
+ * On error, negative error is returned.
+ */
+int btf_check_iter_arg(struct btf *btf, const struct btf_type *func, int arg_idx)
+{
+	const struct btf_param *arg;
+	const struct btf_type *t;
+	const char *name;
+	int btf_id;
+
+	if (btf_type_vlen(func) <= arg_idx)
+		return -EINVAL;
+
+	arg = &btf_params(func)[arg_idx];
+	t = btf_type_skip_modifiers(btf, arg->type, NULL);
+	if (!t || !btf_type_is_ptr(t))
+		return -EINVAL;
+	t = btf_type_skip_modifiers(btf, t->type, &btf_id);
+	if (!t || !__btf_type_is_struct(t))
+		return -EINVAL;
+
+	name = btf_name_by_offset(btf, t->name_off);
+	if (!name || strncmp(name, ITER_PREFIX, sizeof(ITER_PREFIX) - 1))
+		return -EINVAL;
+
+	return btf_id;
+}
+
 static int btf_check_iter_kfuncs(struct btf *btf, const char *func_name,
 				 const struct btf_type *func, u32 func_flags)
 {
 	u32 flags = func_flags & (KF_ITER_NEW | KF_ITER_NEXT | KF_ITER_DESTROY);
-	const char *name, *sfx, *iter_name;
-	const struct btf_param *arg;
+	const char *sfx, *iter_name;
 	const struct btf_type *t;
 	char exp_name[128];
 	u32 nr_args;
+	int btf_id;
 
 	/* exactly one of KF_ITER_{NEW,NEXT,DESTROY} can be set */
 	if (!flags || (flags & (flags - 1)))
@@ -8061,28 +8090,21 @@ static int btf_check_iter_kfuncs(struct btf *btf, const char *func_name,
 	if (nr_args < 1)
 		return -EINVAL;
 
-	arg = &btf_params(func)[0];
-	t = btf_type_skip_modifiers(btf, arg->type, NULL);
-	if (!t || !btf_type_is_ptr(t))
-		return -EINVAL;
-	t = btf_type_skip_modifiers(btf, t->type, NULL);
-	if (!t || !__btf_type_is_struct(t))
-		return -EINVAL;
-
-	name = btf_name_by_offset(btf, t->name_off);
-	if (!name || strncmp(name, ITER_PREFIX, sizeof(ITER_PREFIX) - 1))
-		return -EINVAL;
+	btf_id = btf_check_iter_arg(btf, func, 0);
+	if (btf_id < 0)
+		return btf_id;
 
 	/* sizeof(struct bpf_iter_<type>) should be a multiple of 8 to
 	 * fit nicely in stack slots
 	 */
+	t = btf_type_by_id(btf, btf_id);
 	if (t->size == 0 || (t->size % 8))
 		return -EINVAL;
 
 	/* validate bpf_iter_<type>_{new,next,destroy}(struct bpf_iter_<type> *)
 	 * naming pattern
 	 */
-	iter_name = name + sizeof(ITER_PREFIX) - 1;
+	iter_name = btf_name_by_offset(btf, t->name_off) + sizeof(ITER_PREFIX) - 1;
 	if (flags & KF_ITER_NEW)
 		sfx = "new";
 	else if (flags & KF_ITER_NEXT)

kernel/bpf/verifier.c

@@ -7970,27 +7970,38 @@ static bool is_iter_destroy_kfunc(struct bpf_kfunc_call_arg_meta *meta)
 	return meta->kfunc_flags & KF_ITER_DESTROY;
 }
 
-static bool is_kfunc_arg_iter(struct bpf_kfunc_call_arg_meta *meta, int arg)
+static bool is_kfunc_arg_iter(struct bpf_kfunc_call_arg_meta *meta, int arg_idx,
+			      const struct btf_param *arg)
 {
 	/* btf_check_iter_kfuncs() guarantees that first argument of any iter
 	 * kfunc is iter state pointer
 	 */
-	return arg == 0 && is_iter_kfunc(meta);
+	if (is_iter_kfunc(meta))
+		return arg_idx == 0;
+
+	/* iter passed as an argument to a generic kfunc */
+	return btf_param_match_suffix(meta->btf, arg, "__iter");
 }
 
 static int process_iter_arg(struct bpf_verifier_env *env, int regno, int insn_idx,
 			    struct bpf_kfunc_call_arg_meta *meta)
 {
 	struct bpf_reg_state *regs = cur_regs(env), *reg = &regs[regno];
 	const struct btf_type *t;
-	const struct btf_param *arg;
-	int spi, err, i, nr_slots;
-	u32 btf_id;
+	int spi, err, i, nr_slots, btf_id;
 
-	/* btf_check_iter_kfuncs() ensures we don't need to validate anything here */
-	arg = &btf_params(meta->func_proto)[0];
-	t = btf_type_skip_modifiers(meta->btf, arg->type, NULL);	/* PTR */
-	t = btf_type_skip_modifiers(meta->btf, t->type, &btf_id);	/* STRUCT */
+	/* For iter_{new,next,destroy} functions, btf_check_iter_kfuncs()
+	 * ensures struct convention, so we wouldn't need to do any BTF
+	 * validation here. But given iter state can be passed as a parameter
+	 * to any kfunc, if arg has "__iter" suffix, we need to be a bit more
+	 * conservative here.
+	 */
+	btf_id = btf_check_iter_arg(meta->btf, meta->func_proto, regno - 1);
+	if (btf_id < 0) {
+		verbose(env, "expected valid iter pointer as arg #%d\n", regno);
+		return -EINVAL;
+	}
+	t = btf_type_by_id(meta->btf, btf_id);
 	nr_slots = t->size / BPF_REG_SIZE;
 
 	if (is_iter_new_kfunc(meta)) {
@@ -8012,7 +8023,9 @@ static int process_iter_arg(struct bpf_verifier_env *env, int regno, int insn_id
 		if (err)
 			return err;
 	} else {
-		/* iter_next() or iter_destroy() expect initialized iter state*/
+		/* iter_next() or iter_destroy(), as well as any kfunc
+		 * accepting iter argument, expect initialized iter state
+		 */
 		err = is_iter_reg_valid_init(env, reg, meta->btf, btf_id, nr_slots);
 		switch (err) {
 		case 0:
@@ -11382,7 +11395,7 @@ get_kfunc_ptr_arg_type(struct bpf_verifier_env *env,
 	if (is_kfunc_arg_dynptr(meta->btf, &args[argno]))
 		return KF_ARG_PTR_TO_DYNPTR;
 
-	if (is_kfunc_arg_iter(meta, argno))
+	if (is_kfunc_arg_iter(meta, argno, &args[argno]))
 		return KF_ARG_PTR_TO_ITER;
 
 	if (is_kfunc_arg_list_head(meta->btf, &args[argno]))

tools/testing/selftests/bpf/.gitignore

@@ -8,6 +8,7 @@ test_lru_map
 test_lpm_map
 test_tag
 FEATURE-DUMP.libbpf
+FEATURE-DUMP.selftests
 fixdep
 /test_progs
 /test_progs-no_alu32

tools/testing/selftests/bpf/Makefile

@@ -33,6 +33,13 @@ OPT_FLAGS	?= $(if $(RELEASE),-O2,-O0)
 LIBELF_CFLAGS	:= $(shell $(PKG_CONFIG) libelf --cflags 2>/dev/null)
 LIBELF_LIBS	:= $(shell $(PKG_CONFIG) libelf --libs 2>/dev/null || echo -lelf)
 
+ifeq ($(srctree),)
+srctree := $(patsubst %/,%,$(dir $(CURDIR)))
+srctree := $(patsubst %/,%,$(dir $(srctree)))
+srctree := $(patsubst %/,%,$(dir $(srctree)))
+srctree := $(patsubst %/,%,$(dir $(srctree)))
+endif
+
 CFLAGS += -g $(OPT_FLAGS) -rdynamic					\
 	  -Wall -Werror -fno-omit-frame-pointer				\
 	  $(GENFLAGS) $(SAN_CFLAGS) $(LIBELF_CFLAGS)			\
@@ -60,6 +67,9 @@ progs/timer_crash.c-CFLAGS := -fno-strict-aliasing
 progs/test_global_func9.c-CFLAGS := -fno-strict-aliasing
 progs/verifier_nocsr.c-CFLAGS := -fno-strict-aliasing
 
+# Some utility functions use LLVM libraries
+jit_disasm_helpers.c-CFLAGS = $(LLVM_CFLAGS)
+
 ifneq ($(LLVM),)
 # Silence some warnings when compiled with clang
 CFLAGS += -Wno-unused-command-line-argument
@@ -168,6 +178,31 @@ endef
 
 include ../lib.mk
 
+NON_CHECK_FEAT_TARGETS := clean docs-clean
+CHECK_FEAT := $(filter-out $(NON_CHECK_FEAT_TARGETS),$(or $(MAKECMDGOALS), "none"))
+ifneq ($(CHECK_FEAT),)
+FEATURE_USER := .selftests
+FEATURE_TESTS := llvm
+FEATURE_DISPLAY := $(FEATURE_TESTS)
+
+# Makefile.feature expects OUTPUT to end with a slash
+$(let OUTPUT,$(OUTPUT)/,\
+	$(eval include ../../../build/Makefile.feature))
+endif
+
+ifeq ($(feature-llvm),1)
+  LLVM_CFLAGS  += -DHAVE_LLVM_SUPPORT
+  LLVM_CONFIG_LIB_COMPONENTS := mcdisassembler all-targets
+  # both llvm-config and lib.mk add -D_GNU_SOURCE, which ends up as conflict
+  LLVM_CFLAGS  += $(filter-out -D_GNU_SOURCE,$(shell $(LLVM_CONFIG) --cflags))
+  LLVM_LDLIBS  += $(shell $(LLVM_CONFIG) --libs $(LLVM_CONFIG_LIB_COMPONENTS))
+  ifeq ($(shell $(LLVM_CONFIG) --shared-mode),static)
+    LLVM_LDLIBS += $(shell $(LLVM_CONFIG) --system-libs $(LLVM_CONFIG_LIB_COMPONENTS))
+    LLVM_LDLIBS += -lstdc++
+  endif
+  LLVM_LDFLAGS += $(shell $(LLVM_CONFIG) --ldflags)
+endif
+
 SCRATCH_DIR := $(OUTPUT)/tools
 BUILD_DIR := $(SCRATCH_DIR)/build
 INCLUDE_DIR := $(SCRATCH_DIR)/include
@@ -612,6 +647,10 @@ ifeq ($(filter clean docs-clean,$(MAKECMDGOALS)),)
 include $(wildcard $(TRUNNER_TEST_OBJS:.o=.d))
 endif
 
+# add per extra obj CFGLAGS definitions
+$(foreach N,$(patsubst $(TRUNNER_OUTPUT)/%.o,%,$(TRUNNER_EXTRA_OBJS)),	\
+	$(eval $(TRUNNER_OUTPUT)/$(N).o: CFLAGS += $($(N).c-CFLAGS)))
+
 $(TRUNNER_EXTRA_OBJS): $(TRUNNER_OUTPUT)/%.o:				\
 		       %.c						\
 		       $(TRUNNER_EXTRA_HDRS)				\
@@ -628,6 +667,9 @@ ifneq ($2:$(OUTPUT),:$(shell pwd))
 	$(Q)rsync -aq $$^ $(TRUNNER_OUTPUT)/
 endif
 
+$(OUTPUT)/$(TRUNNER_BINARY): LDLIBS += $$(LLVM_LDLIBS)
+$(OUTPUT)/$(TRUNNER_BINARY): LDFLAGS += $$(LLVM_LDFLAGS)
+
 # some X.test.o files have runtime dependencies on Y.bpf.o files
 $(OUTPUT)/$(TRUNNER_BINARY): | $(TRUNNER_BPF_OBJS)
 
@@ -637,7 +679,7 @@ $(OUTPUT)/$(TRUNNER_BINARY): $(TRUNNER_TEST_OBJS)			\
 			     $(TRUNNER_BPFTOOL)				\
 			     | $(TRUNNER_BINARY)-extras
 	$$(call msg,BINARY,,$$@)
-	$(Q)$$(CC) $$(CFLAGS) $$(filter %.a %.o,$$^) $$(LDLIBS) -o $$@
+	$(Q)$$(CC) $$(CFLAGS) $$(filter %.a %.o,$$^) $$(LDLIBS) $$(LDFLAGS) -o $$@
 	$(Q)$(RESOLVE_BTFIDS) --btf $(TRUNNER_OUTPUT)/btf_data.bpf.o $$@
 	$(Q)ln -sf $(if $2,..,.)/tools/build/bpftool/$(USE_BOOTSTRAP)bpftool \
 		   $(OUTPUT)/$(if $2,$2/)bpftool
@@ -656,6 +698,7 @@ TRUNNER_EXTRA_SOURCES := test_progs.c		\
 			 cap_helpers.c		\
 			 unpriv_helpers.c 	\
 			 netlink_helpers.c	\
+			 jit_disasm_helpers.c	\
 			 test_loader.c		\
 			 xsk.c			\
 			 disasm.c		\
@@ -798,7 +841,8 @@ EXTRA_CLEAN := $(SCRATCH_DIR) $(HOST_SCRATCH_DIR)			\
 	$(addprefix $(OUTPUT)/,*.o *.d *.skel.h *.lskel.h *.subskel.h	\
 			       no_alu32 cpuv4 bpf_gcc bpf_testmod.ko	\
 			       bpf_test_no_cfi.ko			\
-			       liburandom_read.so)
+			       liburandom_read.so)			\
+	$(OUTPUT)/FEATURE-DUMP.selftests
 
 .PHONY: docs docs-clean
 

tools/testing/selftests/bpf/bpf_testmod/bpf_testmod.c

@@ -141,13 +141,12 @@ bpf_testmod_test_mod_kfunc(int i)
 
 __bpf_kfunc int bpf_iter_testmod_seq_new(struct bpf_iter_testmod_seq *it, s64 value, int cnt)
 {
-	if (cnt < 0) {
-		it->cnt = 0;
+	it->cnt = cnt;
+
+	if (cnt < 0)
 		return -EINVAL;
-	}
 
 	it->value = value;
-	it->cnt = cnt;
 
 	return 0;
 }
@@ -162,6 +161,14 @@ __bpf_kfunc s64 *bpf_iter_testmod_seq_next(struct bpf_iter_testmod_seq* it)
 	return &it->value;
 }
 
+__bpf_kfunc s64 bpf_iter_testmod_seq_value(int val, struct bpf_iter_testmod_seq* it__iter)
+{
+	if (it__iter->cnt < 0)
+		return 0;
+
+	return val + it__iter->value;
+}
+
 __bpf_kfunc void bpf_iter_testmod_seq_destroy(struct bpf_iter_testmod_seq *it)
 {
 	it->cnt = 0;
@@ -531,6 +538,7 @@ BTF_KFUNCS_START(bpf_testmod_common_kfunc_ids)
 BTF_ID_FLAGS(func, bpf_iter_testmod_seq_new, KF_ITER_NEW)
 BTF_ID_FLAGS(func, bpf_iter_testmod_seq_next, KF_ITER_NEXT | KF_RET_NULL)
 BTF_ID_FLAGS(func, bpf_iter_testmod_seq_destroy, KF_ITER_DESTROY)
+BTF_ID_FLAGS(func, bpf_iter_testmod_seq_value)
 BTF_ID_FLAGS(func, bpf_kfunc_common_test)
 BTF_ID_FLAGS(func, bpf_kfunc_dynptr_test)
 BTF_ID_FLAGS(func, bpf_testmod_ctx_create, KF_ACQUIRE | KF_RET_NULL)