summaryrefslogtreecommitdiff
path: root/tools/testing/selftests/bpf/progs/exceptions_fail.c
diff options
context:
space:
mode:
authorKumar Kartikeya Dwivedi <memxor@gmail.com>2023-09-13 02:32:14 +0300
committerAlexei Starovoitov <ast@kernel.org>2023-09-16 19:36:43 +0300
commitd2a93715bfb0655a63bb1687f43f48eb2e61717b (patch)
tree2094312e53ff2b27e6aa2cb71fd29cc5b41175c4 /tools/testing/selftests/bpf/progs/exceptions_fail.c
parentd6ea06803212d992cbab24466f491ee0178bf9e0 (diff)
downloadlinux-d2a93715bfb0655a63bb1687f43f48eb2e61717b.tar.xz
selftests/bpf: Add tests for BPF exceptions
Add selftests to cover success and failure cases of API usage, runtime behavior and invariants that need to be maintained for implementation correctness. Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com> Link: https://lore.kernel.org/r/20230912233214.1518551-18-memxor@gmail.com Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Diffstat (limited to 'tools/testing/selftests/bpf/progs/exceptions_fail.c')
-rw-r--r--tools/testing/selftests/bpf/progs/exceptions_fail.c347
1 files changed, 347 insertions, 0 deletions
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";