Merge branch 'exceptions-1-2'

Kumar Kartikeya Dwivedi says:

====================
Exceptions - 1/2

This series implements the _first_ part of the runtime and verifier
support needed to enable BPF exceptions. Exceptions thrown from programs
are processed as an immediate exit from the program, which unwinds all
the active stack frames until the main stack frame, and returns to the
BPF program's caller. The ability to perform this unwinding safely
allows the program to test conditions that are always true at runtime
but which the verifier has no visibility into.

Thus, it also reduces verification effort by safely terminating
redundant paths that can be taken within a program.

The patches to perform runtime resource cleanup during the
frame-by-frame unwinding will be posted as a follow-up to this set.

It must be noted that exceptions are not an error handling mechanism for
unlikely runtime conditions, but a way to safely terminate the execution
of a program in presence of conditions that should never occur at
runtime. They are meant to serve higher-level primitives such as program
assertions.

The following kfuncs and macros are introduced:

Assertion macros are also introduced, please see patch 13 for their
documentation.

/* Description
 *	Throw a BPF exception from the program, immediately terminating its
 *	execution and unwinding the stack. The supplied 'cookie' parameter
 *	will be the return value of the program when an exception is thrown,
 *	and the default exception callback is used. Otherwise, if an exception
 *	callback is set using the '__exception_cb(callback)' declaration tag
 *	on the main program, the 'cookie' parameter will be the callback's only
 *	input argument.
 *
 *	Thus, in case of default exception callback, 'cookie' is subjected to
 *	constraints on the program's return value (as with R0 on exit).
 *	Otherwise, the return value of the marked exception callback will be
 *	subjected to the same checks.
 *
 *	Note that throwing an exception with lingering resources (locks,
 *	references, etc.) will lead to a verification error.
 *
 *	Note that callbacks *cannot* call this helper.
 * Returns
 *	Never.
 * Throws
 *	An exception with the specified 'cookie' value.
 */
extern void bpf_throw(u64 cookie) __ksym;

/* This macro must be used to mark the exception callback corresponding to the
 * main program. For example:
 *
 * int exception_cb(u64 cookie) {
 *	return cookie;
 * }
 *
 * SEC("tc")
 * __exception_cb(exception_cb)
 * int main_prog(struct __sk_buff *ctx) {
 *	...
 *	return TC_ACT_OK;
 * }
 *
 * Here, exception callback for the main program will be 'exception_cb'. Note
 * that this attribute can only be used once, and multiple exception callbacks
 * specified for the main program will lead to verification error.
 */
\#define __exception_cb(name) __attribute__((btf_decl_tag("exception_callback:" #name)))

As such, a program can only install an exception handler once for the
lifetime of a BPF program, and this handler cannot be changed at
runtime. The purpose of the handler is to simply interpret the cookie
value supplied by the bpf_throw call, and execute user-defined logic
corresponding to it. The primary purpose of allowing a handler is to
control the return value of the program. The default handler returns the
cookie value passed to bpf_throw when an exception is thrown.

Fixing the handler for the lifetime of the program eliminates tricky and
expensive handling in case of runtime changes of the handler callback
when programs begin to nest, where it becomes more complex to save and
restore the active handler at runtime.

This version of offline unwinding based BPF exceptions is truly zero
overhead, with the exception of generation of a default callback which
contains a few instructions to return a default return value (0) when no
exception callback is supplied by the user.

Callbacks are disallowed from throwing BPF exceptions for now, since
such exceptions need to cross the callback helper boundary (and
therefore must care about unwinding kernel state), however it is
possible to lift this restriction in the future follow-up.

Exceptions terminate propogating at program boundaries, hence both
BPF_PROG_TYPE_EXT and tail call targets return to their caller context
the return value of the exception callback, in the event that they throw
an exception. Thus, exceptions do not cross extension or tail call
boundary.

However, this is mostly an implementation choice, and can be changed to
suit more user-friendly semantics.

Changelog:
----------
v2 -> v3
v2: https://lore.kernel.org/bpf/20230809114116.3216687-1-memxor@gmail.com

 * Add Dave's Acked-by.
 * Address all comments from Alexei.
   * Use bpf_is_subprog to check for main prog in bpf_stack_walker.
   * Drop accidental leftover hunk in libbpf patch.
   * Split libbpf patch's refactoring to aid review
   * Disable fentry/fexit in addition to freplace for exception cb.
   * Add selftests for fentry/fexit/freplace on exception cb and main prog.
 * Use btf_find_by_name_kind in bpf_find_exception_callback_insn_off (Martin)
 * Split KASAN patch into two to aid backporting (Andrey)
 * Move exception callback append step to bpf_object__reloacte (Andrii)
 * Ensure that the exception callback name is unique (Andrii)
 * Keep ASM implementation of assertion macros instead of C, as it does
   not achieve intended results for bpf_assert_range and other cases.

v1 -> v2
v1: https://lore.kernel.org/bpf/20230713023232.1411523-1-memxor@gmail.com

 * Address all comments from Alexei.
 * Fix a few bugs and corner cases in the implementations found during
   testing. Also add new selftests for these cases.
 * Reinstate patch to consider ksym.end part of the program (but
   reworked to cover other corner cases).
 * Implement new style of tagging exception callbacks, add libbpf
   support for the new declaration tag.
 * Limit support to 64-bit integer types for assertion macros. The
   compiler ends up performing shifts or bitwise and operations when
   finally making use of the value, which defeats the purpose of the
   macro. On noalu32 mode, the shifts may also happen before use,
   hurting reliability.
 * Comprehensively test assertion macros and their side effects on the
   verifier state, register bounds, etc.
 * Fix a KASAN false positive warning.

RFC v1 -> v1
RFC v1: https://lore.kernel.org/bpf/20230405004239.1375399-1-memxor@gmail.com

 * Completely rework the unwinding infrastructure to use offline
   unwinding support.
 * Remove the runtime exception state and program rewriting code.
 * Make bpf_set_exception_callback idempotent to avoid vexing
   synchronization and state clobbering issues in presence of program
   nesting.
 * Disable bpf_throw within callback functions, for now.
 * Allow bpf_throw in tail call programs and extension programs,
   removing limitations of rewrite based unwinding.
 * Expand selftests.
====================

Link: https://lore.kernel.org/r/20230912233214.1518551-1-memxor@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

9 files changed, 1762 insertions, 24 deletions

diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c
index 96ff1aa4bf6a..3a6108e3238b 100644
--- a/tools/lib/bpf/libbpf.c
+++ b/tools/lib/bpf/libbpf.c
@@ -436,9 +436,11 @@ struct bpf_program {
 	int fd;
 	bool autoload;
 	bool autoattach;
+	bool sym_global;
 	bool mark_btf_static;
 	enum bpf_prog_type type;
 	enum bpf_attach_type expected_attach_type;
+	int exception_cb_idx;
 
 	int prog_ifindex;
 	__u32 attach_btf_obj_fd;
@@ -765,6 +767,7 @@ bpf_object__init_prog(struct bpf_object *obj, struct bpf_program *prog,
 
 	prog->type = BPF_PROG_TYPE_UNSPEC;
 	prog->fd = -1;
+	prog->exception_cb_idx = -1;
 
 	/* libbpf's convention for SEC("?abc...") is that it's just like
 	 * SEC("abc...") but the corresponding bpf_program starts out with
@@ -871,14 +874,16 @@ bpf_object__add_programs(struct bpf_object *obj, Elf_Data *sec_data,
 		if (err)
 			return err;
 
+		if (ELF64_ST_BIND(sym->st_info) != STB_LOCAL)
+			prog->sym_global = true;
+
 		/* if function is a global/weak symbol, but has restricted
 		 * (STV_HIDDEN or STV_INTERNAL) visibility, mark its BTF FUNC
 		 * as static to enable more permissive BPF verification mode
 		 * with more outside context available to BPF verifier
 		 */
-		if (ELF64_ST_BIND(sym->st_info) != STB_LOCAL
-		    && (ELF64_ST_VISIBILITY(sym->st_other) == STV_HIDDEN
-			|| ELF64_ST_VISIBILITY(sym->st_other) == STV_INTERNAL))
+		if (prog->sym_global && (ELF64_ST_VISIBILITY(sym->st_other) == STV_HIDDEN
+		    || ELF64_ST_VISIBILITY(sym->st_other) == STV_INTERNAL))
 			prog->mark_btf_static = true;
 
 		nr_progs++;
@@ -3142,6 +3147,86 @@ static int bpf_object__sanitize_and_load_btf(struct bpf_object *obj)
 		}
 	}
 
+	if (!kernel_supports(obj, FEAT_BTF_DECL_TAG))
+		goto skip_exception_cb;
+	for (i = 0; i < obj->nr_programs; i++) {
+		struct bpf_program *prog = &obj->programs[i];
+		int j, k, n;
+
+		if (prog_is_subprog(obj, prog))
+			continue;
+		n = btf__type_cnt(obj->btf);
+		for (j = 1; j < n; j++) {
+			const char *str = "exception_callback:", *name;
+			size_t len = strlen(str);
+			struct btf_type *t;
+
+			t = btf_type_by_id(obj->btf, j);
+			if (!btf_is_decl_tag(t) || btf_decl_tag(t)->component_idx != -1)
+				continue;
+
+			name = btf__str_by_offset(obj->btf, t->name_off);
+			if (strncmp(name, str, len))
+				continue;
+
+			t = btf_type_by_id(obj->btf, t->type);
+			if (!btf_is_func(t) || btf_func_linkage(t) != BTF_FUNC_GLOBAL) {
+				pr_warn("prog '%s': exception_callback:<value> decl tag not applied to the main program\n",
+					prog->name);
+				return -EINVAL;
+			}
+			if (strcmp(prog->name, btf__str_by_offset(obj->btf, t->name_off)))
+				continue;
+			/* Multiple callbacks are specified for the same prog,
+			 * the verifier will eventually return an error for this
+			 * case, hence simply skip appending a subprog.
+			 */
+			if (prog->exception_cb_idx >= 0) {
+				prog->exception_cb_idx = -1;
+				break;
+			}
+
+			name += len;
+			if (str_is_empty(name)) {
+				pr_warn("prog '%s': exception_callback:<value> decl tag contains empty value\n",
+					prog->name);
+				return -EINVAL;
+			}
+
+			for (k = 0; k < obj->nr_programs; k++) {
+				struct bpf_program *subprog = &obj->programs[k];
+
+				if (!prog_is_subprog(obj, subprog))
+					continue;
+				if (strcmp(name, subprog->name))
+					continue;
+				/* Enforce non-hidden, as from verifier point of
+				 * view it expects global functions, whereas the
+				 * mark_btf_static fixes up linkage as static.
+				 */
+				if (!subprog->sym_global || subprog->mark_btf_static) {
+					pr_warn("prog '%s': exception callback %s must be a global non-hidden function\n",
+						prog->name, subprog->name);
+					return -EINVAL;
+				}
+				/* Let's see if we already saw a static exception callback with the same name */
+				if (prog->exception_cb_idx >= 0) {
+					pr_warn("prog '%s': multiple subprogs with same name as exception callback '%s'\n",
+					        prog->name, subprog->name);
+					return -EINVAL;
+				}
+				prog->exception_cb_idx = k;
+				break;
+			}
+
+			if (prog->exception_cb_idx >= 0)
+				continue;
+			pr_warn("prog '%s': cannot find exception callback '%s'\n", prog->name, name);
+			return -ENOENT;
+		}
+	}
+skip_exception_cb:
+
 	sanitize = btf_needs_sanitization(obj);
 	if (sanitize) {
 		const void *raw_data;
@@ -6235,13 +6320,45 @@ static int append_subprog_relos(struct bpf_program *main_prog, struct bpf_progra
 }
 
 static int
+bpf_object__append_subprog_code(struct bpf_object *obj, struct bpf_program *main_prog,
+				struct bpf_program *subprog)
+{
+       struct bpf_insn *insns;
+       size_t new_cnt;
+       int err;
+
+       subprog->sub_insn_off = main_prog->insns_cnt;
+
+       new_cnt = main_prog->insns_cnt + subprog->insns_cnt;
+       insns = libbpf_reallocarray(main_prog->insns, new_cnt, sizeof(*insns));
+       if (!insns) {
+               pr_warn("prog '%s': failed to realloc prog code\n", main_prog->name);
+               return -ENOMEM;
+       }
+       main_prog->insns = insns;
+       main_prog->insns_cnt = new_cnt;
+
+       memcpy(main_prog->insns + subprog->sub_insn_off, subprog->insns,
+              subprog->insns_cnt * sizeof(*insns));
+
+       pr_debug("prog '%s': added %zu insns from sub-prog '%s'\n",
+                main_prog->name, subprog->insns_cnt, subprog->name);
+
+       /* The subprog insns are now appended. Append its relos too. */
+       err = append_subprog_relos(main_prog, subprog);
+       if (err)
+               return err;
+       return 0;
+}
+
+static int
 bpf_object__reloc_code(struct bpf_object *obj, struct bpf_program *main_prog,
 		       struct bpf_program *prog)
 {
-	size_t sub_insn_idx, insn_idx, new_cnt;
+	size_t sub_insn_idx, insn_idx;
 	struct bpf_program *subprog;
-	struct bpf_insn *insns, *insn;
 	struct reloc_desc *relo;
+	struct bpf_insn *insn;
 	int err;
 
 	err = reloc_prog_func_and_line_info(obj, main_prog, prog);
@@ -6316,25 +6433,7 @@ bpf_object__reloc_code(struct bpf_object *obj, struct bpf_program *main_prog,
 		 *   and relocate.
 		 */
 		if (subprog->sub_insn_off == 0) {
-			subprog->sub_insn_off = main_prog->insns_cnt;
-
-			new_cnt = main_prog->insns_cnt + subprog->insns_cnt;
-			insns = libbpf_reallocarray(main_prog->insns, new_cnt, sizeof(*insns));
-			if (!insns) {
-				pr_warn("prog '%s': failed to realloc prog code\n", main_prog->name);
-				return -ENOMEM;
-			}
-			main_prog->insns = insns;
-			main_prog->insns_cnt = new_cnt;
-
-			memcpy(main_prog->insns + subprog->sub_insn_off, subprog->insns,
-			       subprog->insns_cnt * sizeof(*insns));
-
-			pr_debug("prog '%s': added %zu insns from sub-prog '%s'\n",
-				 main_prog->name, subprog->insns_cnt, subprog->name);
-
-			/* The subprog insns are now appended. Append its relos too. */
-			err = append_subprog_relos(main_prog, subprog);
+			err = bpf_object__append_subprog_code(obj, main_prog, subprog);
 			if (err)
 				return err;
 			err = bpf_object__reloc_code(obj, main_prog, subprog);
@@ -6568,6 +6667,25 @@ bpf_object__relocate(struct bpf_object *obj, const char *targ_btf_path)
 				prog->name, err);
 			return err;
 		}
+
+		/* Now, also append exception callback if it has not been done already. */
+		if (prog->exception_cb_idx >= 0) {
+			struct bpf_program *subprog = &obj->programs[prog->exception_cb_idx];
+
+			/* Calling exception callback directly is disallowed, which the
+			 * verifier will reject later. In case it was processed already,
+			 * we can skip this step, otherwise for all other valid cases we
+			 * have to append exception callback now.
+			 */
+			if (subprog->sub_insn_off == 0) {
+				err = bpf_object__append_subprog_code(obj, prog, subprog);
+				if (err)
+					return err;
+				err = bpf_object__reloc_code(obj, prog, subprog);
+				if (err)
+					return err;
+			}
+		}
 	}
 	/* Process data relos for main programs */
 	for (i = 0; i < obj->nr_programs; i++) {
diff --git a/tools/testing/selftests/bpf/DENYLIST.aarch64 b/tools/testing/selftests/bpf/DENYLIST.aarch64
index 7f768d335698..f5065576cae9 100644
--- a/tools/testing/selftests/bpf/DENYLIST.aarch64
+++ b/tools/testing/selftests/bpf/DENYLIST.aarch64
@@ -1,5 +1,6 @@
 bpf_cookie/multi_kprobe_attach_api               # kprobe_multi_link_api_subtest:FAIL:fentry_raw_skel_load unexpected error: -3
 bpf_cookie/multi_kprobe_link_api                 # kprobe_multi_link_api_subtest:FAIL:fentry_raw_skel_load unexpected error: -3
+exceptions					 # JIT does not support calling kfunc bpf_throw: -524
 fexit_sleep                                      # The test never returns. The remaining tests cannot start.
 kprobe_multi_bench_attach                        # bpf_program__attach_kprobe_multi_opts unexpected error: -95
 kprobe_multi_test/attach_api_addrs               # bpf_program__attach_kprobe_multi_opts unexpected error: -95
diff --git a/tools/testing/selftests/bpf/DENYLIST.s390x b/tools/testing/selftests/bpf/DENYLIST.s390x
index 5061d9e24c16..ce6f291665cf 100644
--- a/tools/testing/selftests/bpf/DENYLIST.s390x
+++ b/tools/testing/selftests/bpf/DENYLIST.s390x
@@ -6,6 +6,7 @@ bpf_loop                                 # attaches to __x64_sys_nanosleep
 cgrp_local_storage                       # prog_attach unexpected error: -524                                          (trampoline)
 dynptr/test_dynptr_skb_data
 dynptr/test_skb_readonly
+exceptions				 # JIT does not support calling kfunc bpf_throw				       (exceptions)
 fexit_sleep                              # fexit_skel_load fexit skeleton failed                                       (trampoline)
 get_stack_raw_tp                         # user_stack corrupted user stack                                             (no backchain userspace)
 iters/testmod_seq*                       # s390x doesn't support kfuncs in modules yet
diff --git a/tools/testing/selftests/bpf/bpf_experimental.h b/tools/testing/selftests/bpf/bpf_experimental.h
index 4494eaa9937e..9aa29564bd74 100644
--- a/tools/testing/selftests/bpf/bpf_experimental.h
+++ b/tools/testing/selftests/bpf/bpf_experimental.h
@@ -162,4 +162,292 @@ extern void bpf_percpu_obj_drop_impl(void *kptr, void *meta) __ksym;
 /* Convenience macro to wrap over bpf_obj_drop_impl */
 #define bpf_percpu_obj_drop(kptr) bpf_percpu_obj_drop_impl(kptr, NULL)
 
+/* Description
+ *	Throw a BPF exception from the program, immediately terminating its
+ *	execution and unwinding the stack. The supplied 'cookie' parameter
+ *	will be the return value of the program when an exception is thrown,
+ *	and the default exception callback is used. Otherwise, if an exception
+ *	callback is set using the '__exception_cb(callback)' declaration tag
+ *	on the main program, the 'cookie' parameter will be the callback's only
+ *	input argument.
+ *
+ *	Thus, in case of default exception callback, 'cookie' is subjected to
+ *	constraints on the program's return value (as with R0 on exit).
+ *	Otherwise, the return value of the marked exception callback will be
+ *	subjected to the same checks.
+ *
+ *	Note that throwing an exception with lingering resources (locks,
+ *	references, etc.) will lead to a verification error.
+ *
+ *	Note that callbacks *cannot* call this helper.
+ * Returns
+ *	Never.
+ * Throws
+ *	An exception with the specified 'cookie' value.
+ */
+extern void bpf_throw(u64 cookie) __ksym;
+
+/* This macro must be used to mark the exception callback corresponding to the
+ * main program. For example:
+ *
+ * int exception_cb(u64 cookie) {
+ *	return cookie;
+ * }
+ *
+ * SEC("tc")
+ * __exception_cb(exception_cb)
+ * int main_prog(struct __sk_buff *ctx) {
+ *	...
+ *	return TC_ACT_OK;
+ * }
+ *
+ * Here, exception callback for the main program will be 'exception_cb'. Note
+ * that this attribute can only be used once, and multiple exception callbacks
+ * specified for the main program will lead to verification error.
+ */
+#define __exception_cb(name) __attribute__((btf_decl_tag("exception_callback:" #name)))
+
+#define __bpf_assert_signed(x) _Generic((x), \
+    unsigned long: 0,       \
+    unsigned long long: 0,  \
+    signed long: 1,         \
+    signed long long: 1     \
+)
+
+#define __bpf_assert_check(LHS, op, RHS)								 \
+	_Static_assert(sizeof(&(LHS)), "1st argument must be an lvalue expression");			 \
+	_Static_assert(sizeof(LHS) == 8, "Only 8-byte integers are supported\n");			 \
+	_Static_assert(__builtin_constant_p(__bpf_assert_signed(LHS)), "internal static assert");	 \
+	_Static_assert(__builtin_constant_p((RHS)), "2nd argument must be a constant expression")
+
+#define __bpf_assert(LHS, op, cons, RHS, VAL)							\
+	({											\
+		(void)bpf_throw;								\
+		asm volatile ("if %[lhs] " op " %[rhs] goto +2; r1 = %[value]; call bpf_throw"	\
+			       : : [lhs] "r"(LHS), [rhs] cons(RHS), [value] "ri"(VAL) : );	\
+	})
+
+#define __bpf_assert_op_sign(LHS, op, cons, RHS, VAL, supp_sign)			\
+	({										\
+		__bpf_assert_check(LHS, op, RHS);					\
+		if (__bpf_assert_signed(LHS) && !(supp_sign))				\
+			__bpf_assert(LHS, "s" #op, cons, RHS, VAL);			\
+		else									\
+			__bpf_assert(LHS, #op, cons, RHS, VAL);				\
+	 })
+
+#define __bpf_assert_op(LHS, op, RHS, VAL, supp_sign)					\
+	({										\
+		if (sizeof(typeof(RHS)) == 8) {						\
+			const typeof(RHS) rhs_var = (RHS);				\
+			__bpf_assert_op_sign(LHS, op, "r", rhs_var, VAL, supp_sign);	\
+		} else {								\
+			__bpf_assert_op_sign(LHS, op, "i", RHS, VAL, supp_sign);	\
+		}									\
+	 })
+
+/* Description
+ *	Assert that a conditional expression is true.
+ * Returns
+ *	Void.
+ * Throws
+ *	An exception with the value zero when the assertion fails.
+ */
+#define bpf_assert(cond) if (!(cond)) bpf_throw(0);
+
+/* Description
+ *	Assert that a conditional expression is true.
+ * Returns
+ *	Void.
+ * Throws
+ *	An exception with the specified value when the assertion fails.
+ */
+#define bpf_assert_with(cond, value) if (!(cond)) bpf_throw(value);
+
+/* Description
+ *	Assert that LHS is equal to RHS. This statement updates the known value
+ *	of LHS during verification. Note that RHS must be a constant value, and
+ *	must fit within the data type of LHS.
+ * Returns
+ *	Void.
+ * Throws
+ *	An exception with the value zero when the assertion fails.
+ */
+#define bpf_assert_eq(LHS, RHS)						\
+	({								\
+		barrier_var(LHS);					\
+		__bpf_assert_op(LHS, ==, RHS, 0, true);			\
+	})
+
+/* Description
+ *	Assert that LHS is equal to RHS. This statement updates the known value
+ *	of LHS during verification. Note that RHS must be a constant value, and
+ *	must fit within the data type of LHS.
+ * Returns
+ *	Void.
+ * Throws
+ *	An exception with the specified value when the assertion fails.
+ */
+#define bpf_assert_eq_with(LHS, RHS, value)				\
+	({								\
+		barrier_var(LHS);					\
+		__bpf_assert_op(LHS, ==, RHS, value, true);		\
+	})
+
+/* Description
+ *	Assert that LHS is less than RHS. This statement updates the known
+ *	bounds of LHS during verification. Note that RHS must be a constant
+ *	value, and must fit within the data type of LHS.
+ * Returns
+ *	Void.
+ * Throws
+ *	An exception with the value zero when the assertion fails.
+ */
+#define bpf_assert_lt(LHS, RHS)						\
+	({								\
+		barrier_var(LHS);					\
+		__bpf_assert_op(LHS, <, RHS, 0, false);			\
+	})
+
+/* Description
+ *	Assert that LHS is less than RHS. This statement updates the known
+ *	bounds of LHS during verification. Note that RHS must be a constant
+ *	value, and must fit within the data type of LHS.
+ * Returns
+ *	Void.
+ * Throws
+ *	An exception with the specified value when the assertion fails.
+ */
+#define bpf_assert_lt_with(LHS, RHS, value)				\
+	({								\
+		barrier_var(LHS);					\
+		__bpf_assert_op(LHS, <, RHS, value, false);		\
+	})
+
+/* Description
+ *	Assert that LHS is greater than RHS. This statement updates the known
+ *	bounds of LHS during verification. Note that RHS must be a constant
+ *	value, and must fit within the data type of LHS.
+ * Returns
+ *	Void.
+ * Throws
+ *	An exception with the value zero when the assertion fails.
+ */
+#define bpf_assert_gt(LHS, RHS)						\
+	({								\
+		barrier_var(LHS);					\
+		__bpf_assert_op(LHS, >, RHS, 0, false);			\
+	})
+
+/* Description
+ *	Assert that LHS is greater than RHS. This statement updates the known
+ *	bounds of LHS during verification. Note that RHS must be a constant
+ *	value, and must fit within the data type of LHS.
+ * Returns
+ *	Void.
+ * Throws
+ *	An exception with the specified value when the assertion fails.
+ */
+#define bpf_assert_gt_with(LHS, RHS, value)				\
+	({								\
+		barrier_var(LHS);					\
+		__bpf_assert_op(LHS, >, RHS, value, false);		\
+	})
+
+/* Description
+ *	Assert that LHS is less than or equal to RHS. This statement updates the
+ *	known bounds of LHS during verification. Note that RHS must be a
+ *	constant value, and must fit within the data type of LHS.
+ * Returns
+ *	Void.
+ * Throws
+ *	An exception with the value zero when the assertion fails.
+ */
+#define bpf_assert_le(LHS, RHS)						\
+	({								\
+		barrier_var(LHS);					\
+		__bpf_assert_op(LHS, <=, RHS, 0, false);		\
+	})
+
+/* Description
+ *	Assert that LHS is less than or equal to RHS. This statement updates the
+ *	known bounds of LHS during verification. Note that RHS must be a
+ *	constant value, and must fit within the data type of LHS.
+ * Returns
+ *	Void.
+ * Throws
+ *	An exception with the specified value when the assertion fails.
+ */
+#define bpf_assert_le_with(LHS, RHS, value)				\
+	({								\
+		barrier_var(LHS);					\
+		__bpf_assert_op(LHS, <=, RHS, value, false);		\
+	})
+
+/* Description
+ *	Assert that LHS is greater than or equal to RHS. This statement updates
+ *	the known bounds of LHS during verification. Note that RHS must be a
+ *	constant value, and must fit within the data type of LHS.
+ * Returns
+ *	Void.
+ * Throws
+ *	An exception with the value zero when the assertion fails.
+ */
+#define bpf_assert_ge(LHS, RHS)						\
+	({								\
+		barrier_var(LHS);					\
+		__bpf_assert_op(LHS, >=, RHS, 0, false);		\
+	})
+
+/* Description
+ *	Assert that LHS is greater than or equal to RHS. This statement updates
+ *	the known bounds of LHS during verification. Note that RHS must be a
+ *	constant value, and must fit within the data type of LHS.
+ * Returns
+ *	Void.
+ * Throws
+ *	An exception with the specified value when the assertion fails.
+ */
+#define bpf_assert_ge_with(LHS, RHS, value)				\
+	({								\
+		barrier_var(LHS);					\
+		__bpf_assert_op(LHS, >=, RHS, value, false);		\
+	})
+
+/* Description
+ *	Assert that LHS is in the range [BEG, END] (inclusive of both). This
+ *	statement updates the known bounds of LHS during verification. Note
+ *	that both BEG and END must be constant values, and must fit within the
+ *	data type of LHS.
+ * Returns
+ *	Void.
+ * Throws
+ *	An exception with the value zero when the assertion fails.
+ */
+#define bpf_assert_range(LHS, BEG, END)					\
+	({								\
+		_Static_assert(BEG <= END, "BEG must be <= END");	\
+		barrier_var(LHS);					\
+		__bpf_assert_op(LHS, >=, BEG, 0, false);		\
+		__bpf_assert_op(LHS, <=, END, 0, false);		\
+	})
+
+/* Description
+ *	Assert that LHS is in the range [BEG, END] (inclusive of both). This
+ *	statement updates the known bounds of LHS during verification. Note
+ *	that both BEG and END must be constant values, and must fit within the
+ *	data type of LHS.
+ * Returns
+ *	Void.
+ * Throws
+ *	An exception with the specified value when the assertion fails.
+ */
+#define bpf_assert_range_with(LHS, BEG, END, value)			\
+	({								\
+		_Static_assert(BEG <= END, "BEG must be <= END");	\
+		barrier_var(LHS);					\
+		__bpf_assert_op(LHS, >=, BEG, value, false);		\
+		__bpf_assert_op(LHS, <=, END, value, false);		\
+	})
+
 #endif
diff --git a/tools/testing/selftests/bpf/prog_tests/exceptions.c b/tools/testing/selftests/bpf/prog_tests/exceptions.c
new file mode 100644
index 000000000000..5663e427dc00
--- /dev/null
+++ b/tools/testing/selftests/bpf/prog_tests/exceptions.c
@@ -0,0 +1,408 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <test_progs.h>
+#include <network_helpers.h>
+
+#include "exceptions.skel.h"
+#include "exceptions_ext.skel.h"
+#include "exceptions_fail.skel.h"
+#include "exceptions_assert.skel.h"
+
+static char log_buf[1024 * 1024];
+
+static void test_exceptions_failure(void)
+{
+	RUN_TESTS(exceptions_fail);
+}
+
+static void test_exceptions_success(void)
+{
+	LIBBPF_OPTS(bpf_test_run_opts, ropts,
+		.data_in = &pkt_v4,
+		.data_size_in = sizeof(pkt_v4),
+		.repeat = 1,
+	);
+	struct exceptions_ext *eskel = NULL;
+	struct exceptions *skel;
+	int ret;
+
+	skel = exceptions__open();
+	if (!ASSERT_OK_PTR(skel, "exceptions__open"))
+		return;
+
+	ret = exceptions__load(skel);
+	if (!ASSERT_OK(ret, "exceptions__load"))
+		goto done;
+
+	if (!ASSERT_OK(bpf_map_update_elem(bpf_map__fd(skel->maps.jmp_table), &(int){0},
+					   &(int){bpf_program__fd(skel->progs.exception_tail_call_target)}, BPF_ANY),
+		       "bpf_map_update_elem jmp_table"))
+		goto done;
+
+#define RUN_SUCCESS(_prog, return_val)						  \
+	if (!test__start_subtest(#_prog)) goto _prog##_##return_val;		  \
+	ret = bpf_prog_test_run_opts(bpf_program__fd(skel->progs._prog), &ropts); \
+	ASSERT_OK(ret, #_prog " prog run ret");					  \
+	ASSERT_EQ(ropts.retval, return_val, #_prog " prog run retval");		  \
+	_prog##_##return_val:
+
+	RUN_SUCCESS(exception_throw_always_1, 64);
+	RUN_SUCCESS(exception_throw_always_2, 32);
+	RUN_SUCCESS(exception_throw_unwind_1, 16);
+	RUN_SUCCESS(exception_throw_unwind_2, 32);
+	RUN_SUCCESS(exception_throw_default, 0);
+	RUN_SUCCESS(exception_throw_default_value, 5);
+	RUN_SUCCESS(exception_tail_call, 24);
+	RUN_SUCCESS(exception_ext, 0);
+	RUN_SUCCESS(exception_ext_mod_cb_runtime, 35);
+	RUN_SUCCESS(exception_throw_subprog, 1);
+	RUN_SUCCESS(exception_assert_nz_gfunc, 1);
+	RUN_SUCCESS(exception_assert_zero_gfunc, 1);
+	RUN_SUCCESS(exception_assert_neg_gfunc, 1);
+	RUN_SUCCESS(exception_assert_pos_gfunc, 1);
+	RUN_SUCCESS(exception_assert_negeq_gfunc, 1);
+	RUN_SUCCESS(exception_assert_poseq_gfunc, 1);
+	RUN_SUCCESS(exception_assert_nz_gfunc_with, 1);
+	RUN_SUCCESS(exception_assert_zero_gfunc_with, 1);
+	RUN_SUCCESS(exception_assert_neg_gfunc_with, 1);
+	RUN_SUCCESS(exception_assert_pos_gfunc_with, 1);
+	RUN_SUCCESS(exception_assert_negeq_gfunc_with, 1);
+	RUN_SUCCESS(exception_assert_poseq_gfunc_with, 1);
+	RUN_SUCCESS(exception_bad_assert_nz_gfunc, 0);
+	RUN_SUCCESS(exception_bad_assert_zero_gfunc, 0);
+	RUN_SUCCESS(exception_bad_assert_neg_gfunc, 0);
+	RUN_SUCCESS(exception_bad_assert_pos_gfunc, 0);
+	RUN_SUCCESS(exception_bad_assert_negeq_gfunc, 0);
+	RUN_SUCCESS(exception_bad_assert_poseq_gfunc, 0);
+	RUN_SUCCESS(exception_bad_assert_nz_gfunc_with, 100);
+	RUN_SUCCESS(exception_bad_assert_zero_gfunc_with, 105);
+	RUN_SUCCESS(exception_bad_assert_neg_gfunc_with, 200);
+	RUN_SUCCESS(exception_bad_assert_pos_gfunc_with, 0);
+	RUN_SUCCESS(exception_bad_assert_negeq_gfunc_with, 101);
+	RUN_SUCCESS(exception_bad_assert_poseq_gfunc_with, 99);
+	RUN_SUCCESS(exception_assert_range, 1);
+	RUN_SUCCESS(exception_assert_range_with, 1);
+	RUN_SUCCESS(exception_bad_assert_range, 0);
+	RUN_SUCCESS(exception_bad_assert_range_with, 10);
+
+#define RUN_EXT(load_ret, attach_err, expr, msg, after_link)			  \
+	{									  \
+		LIBBPF_OPTS(bpf_object_open_opts, o, .kernel_log_buf = log_buf,		 \
+						     .kernel_log_size = sizeof(log_buf), \
+						     .kernel_log_level = 2);		 \
+		exceptions_ext__destroy(eskel);					  \
+		eskel = exceptions_ext__open_opts(&o);				  \
+		struct bpf_program *prog = NULL;				  \
+		struct bpf_link *link = NULL;					  \
+		if (!ASSERT_OK_PTR(eskel, "exceptions_ext__open"))		  \
+			goto done;						  \
+		(expr);								  \
+		ASSERT_OK_PTR(bpf_program__name(prog), bpf_program__name(prog));  \
+		if (!ASSERT_EQ(exceptions_ext__load(eskel), load_ret,		  \
+			       "exceptions_ext__load"))	{			  \
+			printf("%s\n", log_buf);				  \
+			goto done;						  \
+		}								  \
+		if (load_ret != 0) {						  \
+			printf("%s\n", log_buf);				  \
+			if (!ASSERT_OK_PTR(strstr(log_buf, msg), "strstr"))	  \
+				goto done;					  \
+		}								  \
+		if (!load_ret && attach_err) {					  \
+			if (!ASSERT_ERR_PTR(link = bpf_program__attach(prog), "attach err")) \
+				goto done;					  \
+		} else if (!load_ret) {						  \
+			if (!ASSERT_OK_PTR(link = bpf_program__attach(prog), "attach ok"))  \
+				goto done;					  \
+			(void)(after_link);					  \
+			bpf_link__destroy(link);				  \
+		}								  \
+	}
+
+	if (test__start_subtest("non-throwing fentry -> exception_cb"))
+		RUN_EXT(-EINVAL, true, ({
+			prog = eskel->progs.pfentry;
+			bpf_program__set_autoload(prog, true);
+			if (!ASSERT_OK(bpf_program__set_attach_target(prog,
+				       bpf_program__fd(skel->progs.exception_ext_mod_cb_runtime),
+				       "exception_cb_mod"), "set_attach_target"))
+				goto done;
+		}), "FENTRY/FEXIT programs cannot attach to exception callback", 0);
+
+	if (test__start_subtest("throwing fentry -> exception_cb"))
+		RUN_EXT(-EINVAL, true, ({
+			prog = eskel->progs.throwing_fentry;
+			bpf_program__set_autoload(prog, true);
+			if (!ASSERT_OK(bpf_program__set_attach_target(prog,
+				       bpf_program__fd(skel->progs.exception_ext_mod_cb_runtime),
+				       "exception_cb_mod"), "set_attach_target"))
+				goto done;
+		}), "FENTRY/FEXIT programs cannot attach to exception callback", 0);
+
+	if (test__start_subtest("non-throwing fexit -> exception_cb"))
+		RUN_EXT(-EINVAL, true, ({
+			prog = eskel->progs.pfexit;
+			bpf_program__set_autoload(prog, true);
+			if (!ASSERT_OK(bpf_program__set_attach_target(prog,
+				       bpf_program__fd(skel->progs.exception_ext_mod_cb_runtime),
+				       "exception_cb_mod"), "set_attach_target"))
+				goto done;
+		}), "FENTRY/FEXIT programs cannot attach to exception callback", 0);
+
+	if (test__start_subtest("throwing fexit -> exception_cb"))
+		RUN_EXT(-EINVAL, true, ({
+			prog = eskel->progs.throwing_fexit;
+			bpf_program__set_autoload(prog, true);
+			if (!ASSERT_OK(bpf_program__set_attach_target(prog,
+				       bpf_program__fd(skel->progs.exception_ext_mod_cb_runtime),
+				       "exception_cb_mod"), "set_attach_target"))
+				goto done;
+		}), "FENTRY/FEXIT programs cannot attach to exception callback", 0);
+
+	if (test__start_subtest("throwing extension (with custom cb) -> exception_cb"))
+		RUN_EXT(-EINVAL, true, ({
+			prog = eskel->progs.throwing_exception_cb_extension;
+			bpf_program__set_autoload(prog, true);
+			if (!ASSERT_OK(bpf_program__set_attach_target(prog,
+				       bpf_program__fd(skel->progs.exception_ext_mod_cb_runtime),
+				       "exception_cb_mod"), "set_attach_target"))
+				goto done;
+		}), "Extension programs cannot attach to exception callback", 0);
+
+	if (test__start_subtest("throwing extension -> global func in exception_cb"))
+		RUN_EXT(0, false, ({
+			prog = eskel->progs.throwing_exception_cb_extension;
+			bpf_program__set_autoload(prog, true);
+			if (!ASSERT_OK(bpf_program__set_attach_target(prog,
+				       bpf_program__fd(skel->progs.exception_ext_mod_cb_runtime),
+				       "exception_cb_mod_global"), "set_attach_target"))
+				goto done;
+		}), "", ({ RUN_SUCCESS(exception_ext_mod_cb_runtime, 131); }));
+
+	if (test__start_subtest("throwing extension (with custom cb) -> global func in exception_cb"))
+		RUN_EXT(0, false, ({
+			prog = eskel->progs.throwing_extension;
+			bpf_program__set_autoload(prog, true);
+			if (!ASSERT_OK(bpf_program__set_attach_target(prog,
+				       bpf_program__fd(skel->progs.exception_ext),
+				       "exception_ext_global"), "set_attach_target"))
+				goto done;
+		}), "", ({ RUN_SUCCESS(exception_ext, 128); }));
+
+	if (test__start_subtest("non-throwing fentry -> non-throwing subprog"))
+		/* non-throwing fentry -> non-throwing subprog : OK */
+		RUN_EXT(0, false, ({
+			prog = eskel->progs.pfentry;
+			bpf_program__set_autoload(prog, true);
+			if (!ASSERT_OK(bpf_program__set_attach_target(prog,
+				       bpf_program__fd(skel->progs.exception_throw_subprog),
+				       "subprog"), "set_attach_target"))
+				goto done;
+		}), "", 0);
+
+	if (test__start_subtest("throwing fentry -> non-throwing subprog"))
+		/* throwing fentry -> non-throwing subprog : OK */
+		RUN_EXT(0, false, ({
+			prog = eskel->progs.throwing_fentry;
+			bpf_program__set_autoload(prog, true);
+			if (!ASSERT_OK(bpf_program__set_attach_target(prog,
+				       bpf_program__fd(skel->progs.exception_throw_subprog),
+				       "subprog"), "set_attach_target"))
+				goto done;
+		}), "", 0);
+
+	if (test__start_subtest("non-throwing fentry -> throwing subprog"))
+		/* non-throwing fentry -> throwing subprog : OK */
+		RUN_EXT(0, false, ({
+			prog = eskel->progs.pfentry;
+			bpf_program__set_autoload(prog, true);
+			if (!ASSERT_OK(bpf_program__set_attach_target(prog,
+				       bpf_program__fd(skel->progs.exception_throw_subprog),
+				       "throwing_subprog"), "set_attach_target"))
+				goto done;
+		}), "", 0);
+
+	if (test__start_subtest("throwing fentry -> throwing subprog"))
+		/* throwing fentry -> throwing subprog : OK */
+		RUN_EXT(0, false, ({
+			prog = eskel->progs.throwing_fentry;
+			bpf_program__set_autoload(prog, true);
+			if (!ASSERT_OK(bpf_program__set_attach_target(prog,
+				       bpf_program__fd(skel->progs.exception_throw_subprog),
+				       "throwing_subprog"), "set_attach_target"))
+				goto done;
+		}), "", 0);
+
+	if (test__start_subtest("non-throwing fexit -> non-throwing subprog"))
+		/* non-throwing fexit -> non-throwing subprog : OK */
+		RUN_EXT(0, false, ({
+			prog = eskel->progs.pfexit;
+			bpf_program__set_autoload(prog, true);
+			if (!ASSERT_OK(bpf_program__set_attach_target(prog,
+				       bpf_program__fd(skel->progs.exception_throw_subprog),
+				       "subprog"), "set_attach_target"))
+				goto done;
+		}), "", 0);
+
+	if (test__start_subtest("throwing fexit -> non-throwing subprog"))
+		/* throwing fexit -> non-throwing subprog : OK */
+		RUN_EXT(0, false, ({
+			prog = eskel->progs.throwing_fexit;
+			bpf_program__set_autoload(prog, true);
+			if (!ASSERT_OK(bpf_program__set_attach_target(prog,
+				       bpf_program__fd(skel->progs.exception_throw_subprog),
+				       "subprog"), "set_attach_target"))
+				goto done;
+		}), "", 0);
+
+	if (test__start_subtest("non-throwing fexit -> throwing subprog"))
+		/* non-throwing fexit -> throwing subprog : OK */
+		RUN_EXT(0, false, ({
+			prog = eskel->progs.pfexit;
+			bpf_program__set_autoload(prog, true);
+			if (!ASSERT_OK(bpf_program__set_attach_target(prog,
+				       bpf_program__fd(skel->progs.exception_throw_subprog),
+				       "throwing_subprog"), "set_attach_target"))
+				goto done;
+		}), "", 0);
+
+	if (test__start_subtest("throwing fexit -> throwing subprog"))
+		/* throwing fexit -> throwing subprog : OK */
+		RUN_EXT(0, false, ({
+			prog = eskel->progs.throwing_fexit;
+			bpf_program__set_autoload(prog, true);
+			if (!ASSERT_OK(bpf_program__set_attach_target(prog,
+				       bpf_program__fd(skel->progs.exception_throw_subprog),
+				       "throwing_subprog"), "set_attach_target"))
+				goto done;
+		}), "", 0);
+
+	/* fmod_ret not allowed for subprog - Check so we remember to handle its
+	 * throwing specification compatibility with target when supported.
+	 */
+	if (test__start_subtest("non-throwing fmod_ret -> non-throwing subprog"))
+		RUN_EXT(-EINVAL, true, ({
+			prog = eskel->progs.pfmod_ret;
+			bpf_program__set_autoload(prog, true);
+			if (!ASSERT_OK(bpf_program__set_attach_target(prog,
+				       bpf_program__fd(skel->progs.exception_throw_subprog),
+				       "subprog"), "set_attach_target"))
+				goto done;
+		}), "can't modify return codes of BPF program", 0);
+
+	/* fmod_ret not allowed for subprog - Check so we remember to handle its
+	 * throwing specification compatibility with target when supported.
+	 */
+	if (test__start_subtest("non-throwing fmod_ret -> non-throwing global subprog"))
+		RUN_EXT(-EINVAL, true, ({
+			prog = eskel->progs.pfmod_ret;
+			bpf_program__set_autoload(prog, true);
+			if (!ASSERT_OK(bpf_program__set_attach_target(prog,
+				       bpf_program__fd(skel->progs.exception_throw_subprog),
+				       "global_subprog"), "set_attach_target"))
+				goto done;
+		}), "can't modify return codes of BPF program", 0);
+
+	if (test__start_subtest("non-throwing extension -> non-throwing subprog"))
+		/* non-throwing extension -> non-throwing subprog : BAD (!global) */
+		RUN_EXT(-EINVAL, true, ({
+			prog = eskel->progs.extension;
+			bpf_program__set_autoload(prog, true);
+			if (!ASSERT_OK(bpf_program__set_attach_target(prog,
+				       bpf_program__fd(skel->progs.exception_throw_subprog),
+				       "subprog"), "set_attach_target"))
+				goto done;
+		}), "subprog() is not a global function", 0);
+
+	if (test__start_subtest("non-throwing extension -> throwing subprog"))
+		/* non-throwing extension -> throwing subprog : BAD (!global) */
+		RUN_EXT(-EINVAL, true, ({
+			prog = eskel->progs.extension;
+			bpf_program__set_autoload(prog, true);
+			if (!ASSERT_OK(bpf_program__set_attach_target(prog,
+				       bpf_program__fd(skel->progs.exception_throw_subprog),
+				       "throwing_subprog"), "set_attach_target"))
+				goto done;
+		}), "throwing_subprog() is not a global function", 0);
+
+	if (test__start_subtest("non-throwing extension -> non-throwing subprog"))
+		/* non-throwing extension -> non-throwing global subprog : OK */
+		RUN_EXT(0, false, ({
+			prog = eskel->progs.extension;
+			bpf_program__set_autoload(prog, true);
+			if (!ASSERT_OK(bpf_program__set_attach_target(prog,
+				       bpf_program__fd(skel->progs.exception_throw_subprog),
+				       "global_subprog"), "set_attach_target"))
+				goto done;
+		}), "", 0);
+
+	if (test__start_subtest("non-throwing extension -> throwing global subprog"))
+		/* non-throwing extension -> throwing global subprog : OK */
+		RUN_EXT(0, false, ({
+			prog = eskel->progs.extension;
+			bpf_program__set_autoload(prog, true);
+			if (!ASSERT_OK(bpf_program__set_attach_target(prog,
+				       bpf_program__fd(skel->progs.exception_throw_subprog),
+				       "throwing_global_subprog"), "set_attach_target"))
+				goto done;
+		}), "", 0);
+
+	if (test__start_subtest("throwing extension -> throwing global subprog"))
+		/* throwing extension -> throwing global subprog : OK */
+		RUN_EXT(0, false, ({
+			prog = eskel->progs.throwing_extension;
+			bpf_program__set_autoload(prog, true);
+			if (!ASSERT_OK(bpf_program__set_attach_target(prog,
+				       bpf_program__fd(skel->progs.exception_throw_subprog),
+				       "throwing_global_subprog"), "set_attach_target"))
+				goto done;
+		}), "", 0);
+
+	if (test__start_subtest("throwing extension -> non-throwing global subprog"))
+		/* throwing extension -> non-throwing global subprog : OK */
+		RUN_EXT(0, false, ({
+			prog = eskel->progs.throwing_extension;
+			bpf_program__set_autoload(prog, true);
+			if (!ASSERT_OK(bpf_program__set_attach_target(prog,
+				       bpf_program__fd(skel->progs.exception_throw_subprog),
+				       "global_subprog"), "set_attach_target"))
+				goto done;
+		}), "", 0);
+
+	if (test__start_subtest("non-throwing extension -> main subprog"))
+		/* non-throwing extension -> main subprog : OK */
+		RUN_EXT(0, false, ({
+			prog = eskel->progs.extension;
+			bpf_program__set_autoload(prog, true);
+			if (!ASSERT_OK(bpf_program__set_attach_target(prog,
+				       bpf_program__fd(skel->progs.exception_throw_subprog),
+				       "exception_throw_subprog"), "set_attach_target"))
+				goto done;
+		}), "", 0);
+
+	if (test__start_subtest("throwing extension -> main subprog"))
+		/* throwing extension -> main subprog : OK */
+		RUN_EXT(0, false, ({
+			prog = eskel->progs.throwing_extension;
+			bpf_program__set_autoload(prog, true);
+			if (!ASSERT_OK(bpf_program__set_attach_target(prog,
+				       bpf_program__fd(skel->progs.exception_throw_subprog),
+				       "exception_throw_subprog"), "set_attach_target"))
+				goto done;
+		}), "", 0);
+
+done:
+	exceptions_ext__destroy(eskel);
+	exceptions__destroy(skel);
+}
+
+static void test_exceptions_assertions(void)
+{
+	RUN_TESTS(exceptions_assert);
+}
+
+void test_exceptions(void)
+{
+	test_exceptions_success();
+	test_exceptions_failure();
+	test_exceptions_assertions();
+}
diff --git a/tools/testing/selftests/bpf/progs/exceptions.c b/tools/testing/selftests/bpf/progs/exceptions.c
new file mode 100644
index 000000000000..2811ee842b01
--- /dev/null
+++ b/tools/testing/selftests/bpf/progs/exceptions.c
@@ -0,0 +1,368 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <vmlinux.h>
+#include <bpf/bpf_tracing.h>
+#include <bpf/bpf_helpers.h>
+#include <bpf/bpf_core_read.h>
+#include <bpf/bpf_endian.h>
+#include "bpf_misc.h"
+#include "bpf_experimental.h"
+
+#ifndef ETH_P_IP
+#define ETH_P_IP 0x0800
+#endif
+
+struct {
+	__uint(type, BPF_MAP_TYPE_PROG_ARRAY);
+	__uint(max_entries, 4);
+	__uint(key_size, sizeof(__u32));
+	__uint(value_size, sizeof(__u32));
+} jmp_table SEC(".maps");
+
+static __noinline int static_func(u64 i)
+{
+	bpf_throw(32);
+	return i;
+}
+
+__noinline int global2static_simple(u64 i)
+{
+	static_func(i + 2);
+	return i - 1;
+}
+
+__noinline int global2static(u64 i)
+{
+	if (i == ETH_P_IP)
+		bpf_throw(16);
+	return static_func(i);
+}
+
+static __noinline int static2global(u64 i)
+{
+	return global2static(i) + i;
+}
+
+SEC("tc")
+int exception_throw_always_1(struct __sk_buff *ctx)
+{
+	bpf_throw(64);
+	return 0;
+}
+
+/* In this case, the global func will never be seen executing after call to
+ * static subprog, hence verifier will DCE the remaining instructions. Ensure we
+ * are resilient to that.
+ */
+SEC("tc")
+int exception_throw_always_2(struct __sk_buff *ctx)
+{
+	return global2static_simple(ctx->protocol);
+}
+
+SEC("tc")
+int exception_throw_unwind_1(struct __sk_buff *ctx)
+{
+	return static2global(bpf_ntohs(ctx->protocol));
+}
+
+SEC("tc")
+int exception_throw_unwind_2(struct __sk_buff *ctx)
+{
+	return static2global(bpf_ntohs(ctx->protocol) - 1);
+}
+
+SEC("tc")
+int exception_throw_default(struct __sk_buff *ctx)
+{
+	bpf_throw(0);
+	return 1;
+}
+
+SEC("tc")
+int exception_throw_default_value(struct __sk_buff *ctx)
+{
+	bpf_throw(5);
+	return 1;
+}
+
+SEC("tc")
+int exception_tail_call_target(struct __sk_buff *ctx)
+{
+	bpf_throw(16);
+	return 0;
+}
+
+static __noinline
+int exception_tail_call_subprog(struct __sk_buff *ctx)
+{
+	volatile int ret = 10;
+
+	bpf_tail_call_static(ctx, &jmp_table, 0);
+	return ret;
+}
+
+SEC("tc")
+int exception_tail_call(struct __sk_buff *ctx) {
+	volatile int ret = 0;
+
+	ret = exception_tail_call_subprog(ctx);
+	return ret + 8;
+}
+
+__noinline int exception_ext_global(struct __sk_buff *ctx)
+{
+	volatile int ret = 0;
+
+	return ret;
+}
+
+static __noinline int exception_ext_static(struct __sk_buff *ctx)
+{
+	return exception_ext_global(ctx);
+}
+
+SEC("tc")
+int exception_ext(struct __sk_buff *ctx)
+{
+	return exception_ext_static(ctx);
+}
+
+__noinline int exception_cb_mod_global(u64 cookie)
+{
+	volatile int ret = 0;
+
+	return ret;
+}
+
+/* Example of how the exception callback supplied during verification can still
+ * introduce extensions by calling to dummy global functions, and alter runtime
+ * behavior.
+ *
+ * Right now we don't allow freplace attachment to exception callback itself,
+ * but if the need arises this restriction is technically feasible to relax in
+ * the future.
+ */
+__noinline int exception_cb_mod(u64 cookie)
+{
+	return exception_cb_mod_global(cookie) + cookie + 10;
+}
+
+SEC("tc")
+__exception_cb(exception_cb_mod)
+int exception_ext_mod_cb_runtime(struct __sk_buff *ctx)
+{
+	bpf_throw(25);
+	return 0;
+}
+
+__noinline static int subprog(struct __sk_buff *ctx)
+{
+	return bpf_ktime_get_ns();
+}
+
+__noinline static int throwing_subprog(struct __sk_buff *ctx)
+{
+	if (ctx->tstamp)
+		bpf_throw(0);
+	return bpf_ktime_get_ns();
+}
+
+__noinline int global_subprog(struct __sk_buff *ctx)
+{
+	return bpf_ktime_get_ns();
+}
+
+__noinline int throwing_global_subprog(struct __sk_buff *ctx)
+{
+	if (ctx->tstamp)
+		bpf_throw(0);
+	return bpf_ktime_get_ns();
+}
+
+SEC("tc")
+int exception_throw_subprog(struct __sk_buff *ctx)
+{
+	switch (ctx->protocol) {
+	case 1:
+		return subprog(ctx);
+	case 2:
+		return global_subprog(ctx);
+	case 3:
+		return throwing_subprog(ctx);
+	case 4:
+		return throwing_global_subprog(ctx);
+	default:
+		break;
+	}
+	bpf_throw(1);
+	return 0;
+}
+
+__noinline int assert_nz_gfunc(u64 c)
+{
+	volatile u64 cookie = c;
+
+	bpf_assert(cookie != 0);
+	return 0;
+}
+
+__noinline int assert_zero_gfunc(u64 c)
+{
+	volatile u64 cookie = c;
+
+	bpf_assert_eq(cookie, 0);
+	return 0;
+}
+
+__noinline int assert_neg_gfunc(s64 c)
+{
+	volatile s64 cookie = c;
+
+	bpf_assert_lt(cookie, 0);
+	return 0;
+}
+
+__noinline int assert_pos_gfunc(s64 c)
+{
+	volatile s64 cookie = c;
+
+	bpf_assert_gt(cookie, 0);
+	return 0;
+}
+
+__noinline int assert_negeq_gfunc(s64 c)
+{
+	volatile s64 cookie = c;
+
+	bpf_assert_le(cookie, -1);
+	return 0;
+}
+
+__noinline int assert_poseq_gfunc(s64 c)
+{
+	volatile s64 cookie = c;
+
+	bpf_assert_ge(cookie, 1);
+	return 0;
+}
+
+__noinline int assert_nz_gfunc_with(u64 c)
+{
+	volatile u64 cookie = c;
+
+	bpf_assert_with(cookie != 0, cookie + 100);
+	return 0;
+}
+
+__noinline int assert_zero_gfunc_with(u64 c)
+{
+	volatile u64 cookie = c;
+
+	bpf_assert_eq_with(cookie, 0, cookie + 100);
+	return 0;
+}
+
+__noinline int assert_neg_gfunc_with(s64 c)
+{
+	volatile s64 cookie = c;
+
+	bpf_assert_lt_with(cookie, 0, cookie + 100);
+	return 0;
+}
+
+__noinline int assert_pos_gfunc_with(s64 c)
+{
+	volatile s64 cookie = c;
+
+	bpf_assert_gt_with(cookie, 0, cookie + 100);
+	return 0;
+}
+
+__noinline int assert_negeq_gfunc_with(s64 c)
+{
+	volatile s64 cookie = c;
+
+	bpf_assert_le_with(cookie, -1, cookie + 100);
+	return 0;
+}
+
+__noinline int assert_poseq_gfunc_with(s64 c)
+{
+	volatile s64 cookie = c;
+
+	bpf_assert_ge_with(cookie, 1, cookie + 100);
+	return 0;
+}
+
+#define check_assert(name, cookie, tag)				\
+SEC("tc")							\
+int exception##tag##name(struct __sk_buff *ctx)			\
+{								\
+	return name(cookie) + 1;				\
+}
+
+check_assert(assert_nz_gfunc, 5, _);
+check_assert(assert_zero_gfunc, 0, _);
+check_assert(assert_neg_gfunc, -100, _);
+check_assert(assert_pos_gfunc, 100, _);
+check_assert(assert_negeq_gfunc, -1, _);
+check_assert(assert_poseq_gfunc, 1, _);
+
+check_assert(assert_nz_gfunc_with, 5, _);
+check_assert(assert_zero_gfunc_with, 0, _);
+check_assert(assert_neg_gfunc_with, -100, _);
+check_assert(assert_pos_gfunc_with, 100, _);
+check_assert(assert_negeq_gfunc_with, -1, _);
+check_assert(assert_poseq_gfunc_with, 1, _);
+
+check_assert(assert_nz_gfunc, 0, _bad_);
+check_assert(assert_zero_gfunc, 5, _bad_);
+check_assert(assert_neg_gfunc, 100, _bad_);
+check_assert(assert_pos_gfunc, -100, _bad_);
+check_assert(assert_negeq_gfunc, 1, _bad_);
+check_assert(assert_poseq_gfunc, -1, _bad_);
+
+check_assert(assert_nz_gfunc_with, 0, _bad_);
+check_assert(assert_zero_gfunc_with, 5, _bad_);
+check_assert(assert_neg_gfunc_with, 100, _bad_);
+check_assert(assert_pos_gfunc_with, -100, _bad_);
+check_assert(assert_negeq_gfunc_with, 1, _bad_);
+check_assert(assert_poseq_gfunc_with, -1, _bad_);
+
+SEC("tc")
+int exception_assert_range(struct __sk_buff *ctx)
+{
+	u64 time = bpf_ktime_get_ns();
+
+	bpf_assert_range(time, 0, ~0ULL);
+	return 1;
+}
+
+SEC("tc")
+int exception_assert_range_with(struct __sk_buff *ctx)
+{
+	u64 time = bpf_ktime_get_ns();
+
+	bpf_assert_range_with(time, 0, ~0ULL, 10);
+	return 1;
+}
+
+SEC("tc")
+int exception_bad_assert_range(struct __sk_buff *ctx)
+{
+	u64 time = bpf_ktime_get_ns();
+
+	bpf_assert_range(time, -100, 100);
+	return 1;
+}
+
+SEC("tc")
+int exception_bad_assert_range_with(struct __sk_buff *ctx)
+{
+	u64 time = bpf_ktime_get_ns();
+
+	bpf_assert_range_with(time, -1000, 1000, 10);
+	return 1;
+}
+
+char _license[] SEC("license") = "GPL";
diff --git a/tools/testing/selftests/bpf/progs/exceptions_assert.c b/tools/testing/selftests/bpf/progs/exceptions_assert.c
new file mode 100644
index 000000000000..fa35832e6748
--- /dev/null
+++ b/tools/testing/selftests/bpf/progs/exceptions_assert.c
@@ -0,0 +1,135 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <vmlinux.h>
+#include <limits.h>
+#include <bpf/bpf_tracing.h>
+#include <bpf/bpf_helpers.h>
+#include <bpf/bpf_core_read.h>
+#include <bpf/bpf_endian.h>
+#include "bpf_misc.h"
+#include "bpf_experimental.h"
+
+#define check_assert(type, op, name, value)				\
+	SEC("?tc")							\
+	__log_level(2) __failure					\
+	int check_assert_##op##_##name(void *ctx)			\
+	{								\
+		type num = bpf_ktime_get_ns();				\
+		bpf_assert_##op(num, value);				\
+		return *(u64 *)num;					\
+	}
+
+__msg(": R0_w=-2147483648 R10=fp0")
+check_assert(s64, eq, int_min, INT_MIN);
+__msg(": R0_w=2147483647 R10=fp0")
+check_assert(s64, eq, int_max, INT_MAX);
+__msg(": R0_w=0 R10=fp0")
+check_assert(s64, eq, zero, 0);
+__msg(": R0_w=-9223372036854775808 R1_w=-9223372036854775808 R10=fp0")
+check_assert(s64, eq, llong_min, LLONG_MIN);
+__msg(": R0_w=9223372036854775807 R1_w=9223372036854775807 R10=fp0")
+check_assert(s64, eq, llong_max, LLONG_MAX);
+
+__msg(": R0_w=scalar(smax=2147483646) R10=fp0")
+check_assert(s64, lt, pos, INT_MAX);
+__msg(": R0_w=scalar(umin=9223372036854775808,var_off=(0x8000000000000000; 0x7fffffffffffffff))")
+check_assert(s64, lt, zero, 0);
+__msg(": R0_w=scalar(umin=9223372036854775808,umax=18446744071562067967,var_off=(0x8000000000000000; 0x7fffffffffffffff))")
+check_assert(s64, lt, neg, INT_MIN);
+
+__msg(": R0_w=scalar(smax=2147483647) R10=fp0")
+check_assert(s64, le, pos, INT_MAX);
+__msg(": R0_w=scalar(smax=0) R10=fp0")
+check_assert(s64, le, zero, 0);
+__msg(": R0_w=scalar(umin=9223372036854775808,umax=18446744071562067968,var_off=(0x8000000000000000; 0x7fffffffffffffff))")
+check_assert(s64, le, neg, INT_MIN);
+
+__msg(": R0_w=scalar(umin=2147483648,umax=9223372036854775807,var_off=(0x0; 0x7fffffffffffffff))")
+check_assert(s64, gt, pos, INT_MAX);
+__msg(": R0_w=scalar(umin=1,umax=9223372036854775807,var_off=(0x0; 0x7fffffffffffffff))")
+check_assert(s64, gt, zero, 0);
+__msg(": R0_w=scalar(smin=-2147483647) R10=fp0")
+check_assert(s64, gt, neg, INT_MIN);
+
+__msg(": R0_w=scalar(umin=2147483647,umax=9223372036854775807,var_off=(0x0; 0x7fffffffffffffff))")
+check_assert(s64, ge, pos, INT_MAX);
+__msg(": R0_w=scalar(umax=9223372036854775807,var_off=(0x0; 0x7fffffffffffffff)) R10=fp0")
+check_assert(s64, ge, zero, 0);
+__msg(": R0_w=scalar(smin=-2147483648) R10=fp0")
+check_assert(s64, ge, neg, INT_MIN);
+
+SEC("?tc")
+__log_level(2) __failure
+__msg(": R0=0 R1=ctx(off=0,imm=0) R2=scalar(smin=-2147483646,smax=2147483645) R10=fp0")
+int check_assert_range_s64(struct __sk_buff *ctx)
+{
+	struct bpf_sock *sk = ctx->sk;
+	s64 num;
+
+	_Static_assert(_Generic((sk->rx_queue_mapping), s32: 1, default: 0), "type match");
+	if (!sk)
+		return 0;
+	num = sk->rx_queue_mapping;
+	bpf_assert_range(num, INT_MIN + 2, INT_MAX - 2);
+	return *((u8 *)ctx + num);
+}
+
+SEC("?tc")
+__log_level(2) __failure
+__msg(": R1=ctx(off=0,imm=0) R2=scalar(umin=4096,umax=8192,var_off=(0x0; 0x3fff))")
+int check_assert_range_u64(struct __sk_buff *ctx)
+{
+	u64 num = ctx->len;
+
+	bpf_assert_range(num, 4096, 8192);
+	return *((u8 *)ctx + num);
+}
+
+SEC("?tc")
+__log_level(2) __failure
+__msg(": R0=0 R1=ctx(off=0,imm=0) R2=4096 R10=fp0")
+int check_assert_single_range_s64(struct __sk_buff *ctx)
+{
+	struct bpf_sock *sk = ctx->sk;
+	s64 num;
+
+	_Static_assert(_Generic((sk->rx_queue_mapping), s32: 1, default: 0), "type match");
+	if (!sk)
+		return 0;
+	num = sk->rx_queue_mapping;
+
+	bpf_assert_range(num, 4096, 4096);
+	return *((u8 *)ctx + num);
+}
+
+SEC("?tc")
+__log_level(2) __failure
+__msg(": R1=ctx(off=0,imm=0) R2=4096 R10=fp0")
+int check_assert_single_range_u64(struct __sk_buff *ctx)
+{
+	u64 num = ctx->len;
+
+	bpf_assert_range(num, 4096, 4096);
+	return *((u8 *)ctx + num);
+}
+
+SEC("?tc")
+__log_level(2) __failure
+__msg(": R1=pkt(off=64,r=64,imm=0) R2=pkt_end(off=0,imm=0) R6=pkt(off=0,r=64,imm=0) R10=fp0")
+int check_assert_generic(struct __sk_buff *ctx)
+{
+	u8 *data_end = (void *)(long)ctx->data_end;
+	u8 *data = (void *)(long)ctx->data;
+
+	bpf_assert(data + 64 <= data_end);
+	return data[128];
+}
+
+SEC("?fentry/bpf_check")
+__failure __msg("At program exit the register R0 has value (0x40; 0x0)")
+int check_assert_with_return(void *ctx)
+{
+	bpf_assert_with(!ctx, 64);
+	return 0;
+}
+
+char _license[] SEC("license") = "GPL";
diff --git a/tools/testing/selftests/bpf/progs/exceptions_ext.c b/tools/testing/selftests/bpf/progs/exceptions_ext.c
new file mode 100644
index 000000000000..743c05185d9b
--- /dev/null
+++ b/tools/testing/selftests/bpf/progs/exceptions_ext.c
@@ -0,0 +1,72 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <vmlinux.h>
+#include <bpf/bpf_helpers.h>
+#include "bpf_experimental.h"
+
+SEC("?fentry")
+int pfentry(void *ctx)
+{
+	return 0;
+}
+
+SEC("?fentry")
+int throwing_fentry(void *ctx)
+{
+	bpf_throw(0);
+	return 0;
+}
+
+__noinline int exception_cb(u64 cookie)
+{
+	return cookie + 64;
+}
+
+SEC("?freplace")
+int extension(struct __sk_buff *ctx)
+{
+	return 0;
+}
+
+SEC("?freplace")
+__exception_cb(exception_cb)
+int throwing_exception_cb_extension(u64 cookie)
+{
+	bpf_throw(32);
+	return 0;
+}
+
+SEC("?freplace")
+__exception_cb(exception_cb)
+int throwing_extension(struct __sk_buff *ctx)
+{
+	bpf_throw(64);
+	return 0;
+}
+
+SEC("?fexit")
+int pfexit(void *ctx)
+{
+	return 0;
+}
+
+SEC("?fexit")
+int throwing_fexit(void *ctx)
+{
+	bpf_throw(0);
+	return 0;
+}
+
+SEC("?fmod_ret")
+int pfmod_ret(void *ctx)
+{
+	return 0;
+}
+
+SEC("?fmod_ret")
+int throwing_fmod_ret(void *ctx)
+{
+	bpf_throw(0);
+	return 0;
+}
+
+char _license[] SEC("license") = "GPL";
diff --git a/tools/testing/selftests/bpf/progs/exceptions_fail.c b/tools/testing/selftests/bpf/progs/exceptions_fail.c
new file mode 100644
index 000000000000..4c39e920dac2
--- /dev/null
+++ b/tools/testing/selftests/bpf/progs/exceptions_fail.c
@@ -0,0 +1,347 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <vmlinux.h>
+#include <bpf/bpf_tracing.h>
+#include <bpf/bpf_helpers.h>
+#include <bpf/bpf_core_read.h>
+
+#include "bpf_misc.h"
+#include "bpf_experimental.h"
+
+extern void bpf_rcu_read_lock(void) __ksym;
+
+#define private(name) SEC(".bss." #name) __hidden __attribute__((aligned(8)))
+
+struct foo {
+	struct bpf_rb_node node;
+};
+
+struct hmap_elem {
+	struct bpf_timer timer;
+};
+
+struct {
+	__uint(type, BPF_MAP_TYPE_HASH);
+	__uint(max_entries, 64);
+	__type(key, int);
+	__type(value, struct hmap_elem);
+} hmap SEC(".maps");
+
+private(A) struct bpf_spin_lock lock;
+private(A) struct bpf_rb_root rbtree __contains(foo, node);
+
+__noinline void *exception_cb_bad_ret_type(u64 cookie)
+{
+	return NULL;
+}
+
+__noinline int exception_cb_bad_arg_0(void)
+{
+	return 0;
+}
+
+__noinline int exception_cb_bad_arg_2(int a, int b)
+{
+	return 0;
+}
+
+__noinline int exception_cb_ok_arg_small(int a)
+{
+	return 0;
+}
+
+SEC("?tc")
+__exception_cb(exception_cb_bad_ret_type)
+__failure __msg("Global function exception_cb_bad_ret_type() doesn't return scalar.")
+int reject_exception_cb_type_1(struct __sk_buff *ctx)
+{
+	bpf_throw(0);
+	return 0;
+}
+
+SEC("?tc")
+__exception_cb(exception_cb_bad_arg_0)
+__failure __msg("exception cb only supports single integer argument")
+int reject_exception_cb_type_2(struct __sk_buff *ctx)
+{
+	bpf_throw(0);
+	return 0;
+}
+
+SEC("?tc")
+__exception_cb(exception_cb_bad_arg_2)
+__failure __msg("exception cb only supports single integer argument")
+int reject_exception_cb_type_3(struct __sk_buff *ctx)
+{
+	bpf_throw(0);
+	return 0;
+}
+
+SEC("?tc")
+__exception_cb(exception_cb_ok_arg_small)
+__success
+int reject_exception_cb_type_4(struct __sk_buff *ctx)
+{
+	bpf_throw(0);
+	return 0;
+}
+
+__noinline
+static int timer_cb(void *map, int *key, struct bpf_timer *timer)
+{
+	bpf_throw(0);
+	return 0;
+}
+
+SEC("?tc")
+__failure __msg("cannot be called from callback subprog")
+int reject_async_callback_throw(struct __sk_buff *ctx)
+{
+	struct hmap_elem *elem;
+
+	elem = bpf_map_lookup_elem(&hmap, &(int){0});
+	if (!elem)
+		return 0;
+	return bpf_timer_set_callback(&elem->timer, timer_cb);
+}
+
+__noinline static int subprog_lock(struct __sk_buff *ctx)
+{
+	volatile int ret = 0;
+
+	bpf_spin_lock(&lock);
+	if (ctx->len)
+		bpf_throw(0);
+	return ret;
+}
+
+SEC("?tc")
+__failure __msg("function calls are not allowed while holding a lock")
+int reject_with_lock(void *ctx)
+{
+	bpf_spin_lock(&lock);
+	bpf_throw(0);
+	return 0;
+}
+
+SEC("?tc")
+__failure __msg("function calls are not allowed while holding a lock")
+int reject_subprog_with_lock(void *ctx)
+{
+	return subprog_lock(ctx);
+}
+
+SEC("?tc")
+__failure __msg("bpf_rcu_read_unlock is missing")
+int reject_with_rcu_read_lock(void *ctx)
+{
+	bpf_rcu_read_lock();
+	bpf_throw(0);
+	return 0;
+}
+
+__noinline static int throwing_subprog(struct __sk_buff *ctx)
+{
+	if (ctx->len)
+		bpf_throw(0);
+	return 0;
+}
+
+SEC("?tc")
+__failure __msg("bpf_rcu_read_unlock is missing")
+int reject_subprog_with_rcu_read_lock(void *ctx)
+{
+	bpf_rcu_read_lock();
+	return throwing_subprog(ctx);
+}
+
+static bool rbless(struct bpf_rb_node *n1, const struct bpf_rb_node *n2)
+{
+	bpf_throw(0);
+	return true;
+}
+
+SEC("?tc")
+__failure __msg("function calls are not allowed while holding a lock")
+int reject_with_rbtree_add_throw(void *ctx)
+{
+	struct foo *f;
+
+	f = bpf_obj_new(typeof(*f));
+	if (!f)
+		return 0;
+	bpf_spin_lock(&lock);
+	bpf_rbtree_add(&rbtree, &f->node, rbless);
+	return 0;
+}
+
+SEC("?tc")
+__failure __msg("Unreleased reference")
+int reject_with_reference(void *ctx)
+{
+	struct foo *f;
+
+	f = bpf_obj_new(typeof(*f));
+	if (!f)
+		return 0;
+	bpf_throw(0);
+	return 0;
+}
+
+__noinline static int subprog_ref(struct __sk_buff *ctx)
+{
+	struct foo *f;
+
+	f = bpf_obj_new(typeof(*f));
+	if (!f)
+		return 0;
+	bpf_throw(0);
+	return 0;
+}
+
+__noinline static int subprog_cb_ref(u32 i, void *ctx)
+{
+	bpf_throw(0);
+	return 0;
+}
+
+SEC("?tc")
+__failure __msg("Unreleased reference")
+int reject_with_cb_reference(void *ctx)
+{
+	struct foo *f;
+
+	f = bpf_obj_new(typeof(*f));
+	if (!f)
+		return 0;
+	bpf_loop(5, subprog_cb_ref, NULL, 0);
+	return 0;
+}
+
+SEC("?tc")
+__failure __msg("cannot be called from callback")
+int reject_with_cb(void *ctx)
+{
+	bpf_loop(5, subprog_cb_ref, NULL, 0);
+	return 0;
+}
+
+SEC("?tc")
+__failure __msg("Unreleased reference")
+int reject_with_subprog_reference(void *ctx)
+{
+	return subprog_ref(ctx) + 1;
+}
+
+__noinline int throwing_exception_cb(u64 c)
+{
+	bpf_throw(0);
+	return c;
+}
+
+__noinline int exception_cb1(u64 c)
+{
+	return c;
+}
+
+__noinline int exception_cb2(u64 c)
+{
+	return c;
+}
+
+static __noinline int static_func(struct __sk_buff *ctx)
+{
+	return exception_cb1(ctx->tstamp);
+}
+
+__noinline int global_func(struct __sk_buff *ctx)
+{
+	return exception_cb1(ctx->tstamp);
+}
+
+SEC("?tc")
+__exception_cb(throwing_exception_cb)
+__failure __msg("cannot be called from callback subprog")
+int reject_throwing_exception_cb(struct __sk_buff *ctx)
+{
+	return 0;
+}
+
+SEC("?tc")
+__exception_cb(exception_cb1)
+__failure __msg("cannot call exception cb directly")
+int reject_exception_cb_call_global_func(struct __sk_buff *ctx)
+{
+	return global_func(ctx);
+}
+
+SEC("?tc")
+__exception_cb(exception_cb1)
+__failure __msg("cannot call exception cb directly")
+int reject_exception_cb_call_static_func(struct __sk_buff *ctx)
+{
+	return static_func(ctx);
+}
+
+SEC("?tc")
+__exception_cb(exception_cb1)
+__exception_cb(exception_cb2)
+__failure __msg("multiple exception callback tags for main subprog")
+int reject_multiple_exception_cb(struct __sk_buff *ctx)
+{
+	bpf_throw(0);
+	return 16;
+}
+
+__noinline int exception_cb_bad_ret(u64 c)
+{
+	return c;
+}
+
+SEC("?fentry/bpf_check")
+__exception_cb(exception_cb_bad_ret)
+__failure __msg("At program exit the register R0 has unknown scalar value should")
+int reject_set_exception_cb_bad_ret1(void *ctx)
+{
+	return 0;
+}
+
+SEC("?fentry/bpf_check")
+__failure __msg("At program exit the register R0 has value (0x40; 0x0) should")
+int reject_set_exception_cb_bad_ret2(void *ctx)
+{
+	bpf_throw(64);
+	return 0;
+}
+
+__noinline static int loop_cb1(u32 index, int *ctx)
+{
+	bpf_throw(0);
+	return 0;
+}
+
+__noinline static int loop_cb2(u32 index, int *ctx)
+{
+	bpf_throw(0);
+	return 0;
+}
+
+SEC("?tc")
+__failure __msg("cannot be called from callback")
+int reject_exception_throw_cb(struct __sk_buff *ctx)
+{
+	bpf_loop(5, loop_cb1, NULL, 0);
+	return 0;
+}
+
+SEC("?tc")
+__failure __msg("cannot be called from callback")
+int reject_exception_throw_cb_diff(struct __sk_buff *ctx)
+{
+	if (ctx->protocol)
+		bpf_loop(5, loop_cb1, NULL, 0);
+	else
+		bpf_loop(5, loop_cb2, NULL, 0);
+	return 0;
+}
+
+char _license[] SEC("license") = "GPL";