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-rw-r--r--tools/testing/selftests/bpf/progs/rbtree_fail.c322
1 files changed, 322 insertions, 0 deletions
diff --git a/tools/testing/selftests/bpf/progs/rbtree_fail.c b/tools/testing/selftests/bpf/progs/rbtree_fail.c
new file mode 100644
index 000000000000..bf3cba115897
--- /dev/null
+++ b/tools/testing/selftests/bpf/progs/rbtree_fail.c
@@ -0,0 +1,322 @@
+// 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_experimental.h"
+#include "bpf_misc.h"
+
+struct node_data {
+ long key;
+ long data;
+ struct bpf_rb_node node;
+};
+
+#define private(name) SEC(".data." #name) __hidden __attribute__((aligned(8)))
+private(A) struct bpf_spin_lock glock;
+private(A) struct bpf_rb_root groot __contains(node_data, node);
+private(A) struct bpf_rb_root groot2 __contains(node_data, node);
+
+static bool less(struct bpf_rb_node *a, const struct bpf_rb_node *b)
+{
+ struct node_data *node_a;
+ struct node_data *node_b;
+
+ node_a = container_of(a, struct node_data, node);
+ node_b = container_of(b, struct node_data, node);
+
+ return node_a->key < node_b->key;
+}
+
+SEC("?tc")
+__failure __msg("bpf_spin_lock at off=16 must be held for bpf_rb_root")
+long rbtree_api_nolock_add(void *ctx)
+{
+ struct node_data *n;
+
+ n = bpf_obj_new(typeof(*n));
+ if (!n)
+ return 1;
+
+ bpf_rbtree_add(&groot, &n->node, less);
+ return 0;
+}
+
+SEC("?tc")
+__failure __msg("bpf_spin_lock at off=16 must be held for bpf_rb_root")
+long rbtree_api_nolock_remove(void *ctx)
+{
+ struct node_data *n;
+
+ n = bpf_obj_new(typeof(*n));
+ if (!n)
+ return 1;
+
+ bpf_spin_lock(&glock);
+ bpf_rbtree_add(&groot, &n->node, less);
+ bpf_spin_unlock(&glock);
+
+ bpf_rbtree_remove(&groot, &n->node);
+ return 0;
+}
+
+SEC("?tc")
+__failure __msg("bpf_spin_lock at off=16 must be held for bpf_rb_root")
+long rbtree_api_nolock_first(void *ctx)
+{
+ bpf_rbtree_first(&groot);
+ return 0;
+}
+
+SEC("?tc")
+__failure __msg("rbtree_remove node input must be non-owning ref")
+long rbtree_api_remove_unadded_node(void *ctx)
+{
+ struct node_data *n, *m;
+ struct bpf_rb_node *res;
+
+ n = bpf_obj_new(typeof(*n));
+ if (!n)
+ return 1;
+
+ m = bpf_obj_new(typeof(*m));
+ if (!m) {
+ bpf_obj_drop(n);
+ return 1;
+ }
+
+ bpf_spin_lock(&glock);
+ bpf_rbtree_add(&groot, &n->node, less);
+
+ /* This remove should pass verifier */
+ res = bpf_rbtree_remove(&groot, &n->node);
+ n = container_of(res, struct node_data, node);
+
+ /* This remove shouldn't, m isn't in an rbtree */
+ res = bpf_rbtree_remove(&groot, &m->node);
+ m = container_of(res, struct node_data, node);
+ bpf_spin_unlock(&glock);
+
+ if (n)
+ bpf_obj_drop(n);
+ if (m)
+ bpf_obj_drop(m);
+ return 0;
+}
+
+SEC("?tc")
+__failure __msg("Unreleased reference id=2 alloc_insn=11")
+long rbtree_api_remove_no_drop(void *ctx)
+{
+ struct bpf_rb_node *res;
+ struct node_data *n;
+
+ bpf_spin_lock(&glock);
+ res = bpf_rbtree_first(&groot);
+ if (!res)
+ goto unlock_err;
+
+ res = bpf_rbtree_remove(&groot, res);
+
+ n = container_of(res, struct node_data, node);
+ bpf_spin_unlock(&glock);
+
+ /* bpf_obj_drop(n) is missing here */
+ return 0;
+
+unlock_err:
+ bpf_spin_unlock(&glock);
+ return 1;
+}
+
+SEC("?tc")
+__failure __msg("arg#1 expected pointer to allocated object")
+long rbtree_api_add_to_multiple_trees(void *ctx)
+{
+ struct node_data *n;
+
+ n = bpf_obj_new(typeof(*n));
+ if (!n)
+ return 1;
+
+ bpf_spin_lock(&glock);
+ bpf_rbtree_add(&groot, &n->node, less);
+
+ /* This add should fail since n already in groot's tree */
+ bpf_rbtree_add(&groot2, &n->node, less);
+ bpf_spin_unlock(&glock);
+ return 0;
+}
+
+SEC("?tc")
+__failure __msg("rbtree_remove node input must be non-owning ref")
+long rbtree_api_add_release_unlock_escape(void *ctx)
+{
+ struct node_data *n;
+
+ n = bpf_obj_new(typeof(*n));
+ if (!n)
+ return 1;
+
+ bpf_spin_lock(&glock);
+ bpf_rbtree_add(&groot, &n->node, less);
+ bpf_spin_unlock(&glock);
+
+ bpf_spin_lock(&glock);
+ /* After add() in previous critical section, n should be
+ * release_on_unlock and released after previous spin_unlock,
+ * so should not be possible to use it here
+ */
+ bpf_rbtree_remove(&groot, &n->node);
+ bpf_spin_unlock(&glock);
+ return 0;
+}
+
+SEC("?tc")
+__failure __msg("rbtree_remove node input must be non-owning ref")
+long rbtree_api_release_aliasing(void *ctx)
+{
+ struct node_data *n, *m, *o;
+ struct bpf_rb_node *res;
+
+ n = bpf_obj_new(typeof(*n));
+ if (!n)
+ return 1;
+
+ bpf_spin_lock(&glock);
+ bpf_rbtree_add(&groot, &n->node, less);
+ bpf_spin_unlock(&glock);
+
+ bpf_spin_lock(&glock);
+
+ /* m and o point to the same node,
+ * but verifier doesn't know this
+ */
+ res = bpf_rbtree_first(&groot);
+ if (!res)
+ return 1;
+ o = container_of(res, struct node_data, node);
+
+ res = bpf_rbtree_first(&groot);
+ if (!res)
+ return 1;
+ m = container_of(res, struct node_data, node);
+
+ bpf_rbtree_remove(&groot, &m->node);
+ /* This second remove shouldn't be possible. Retval of previous
+ * remove returns owning reference to m, which is the same
+ * node o's non-owning ref is pointing at
+ *
+ * In order to preserve property
+ * * owning ref must not be in rbtree
+ * * non-owning ref must be in rbtree
+ *
+ * o's ref must be invalidated after previous remove. Otherwise
+ * we'd have non-owning ref to node that isn't in rbtree, and
+ * verifier wouldn't be able to use type system to prevent remove
+ * of ref that already isn't in any tree. Would have to do runtime
+ * checks in that case.
+ */
+ bpf_rbtree_remove(&groot, &o->node);
+
+ bpf_spin_unlock(&glock);
+ return 0;
+}
+
+SEC("?tc")
+__failure __msg("rbtree_remove node input must be non-owning ref")
+long rbtree_api_first_release_unlock_escape(void *ctx)
+{
+ struct bpf_rb_node *res;
+ struct node_data *n;
+
+ bpf_spin_lock(&glock);
+ res = bpf_rbtree_first(&groot);
+ if (res)
+ n = container_of(res, struct node_data, node);
+ bpf_spin_unlock(&glock);
+
+ bpf_spin_lock(&glock);
+ /* After first() in previous critical section, n should be
+ * release_on_unlock and released after previous spin_unlock,
+ * so should not be possible to use it here
+ */
+ bpf_rbtree_remove(&groot, &n->node);
+ bpf_spin_unlock(&glock);
+ return 0;
+}
+
+static bool less__bad_fn_call_add(struct bpf_rb_node *a, const struct bpf_rb_node *b)
+{
+ struct node_data *node_a;
+ struct node_data *node_b;
+
+ node_a = container_of(a, struct node_data, node);
+ node_b = container_of(b, struct node_data, node);
+ bpf_rbtree_add(&groot, &node_a->node, less);
+
+ return node_a->key < node_b->key;
+}
+
+static bool less__bad_fn_call_remove(struct bpf_rb_node *a, const struct bpf_rb_node *b)
+{
+ struct node_data *node_a;
+ struct node_data *node_b;
+
+ node_a = container_of(a, struct node_data, node);
+ node_b = container_of(b, struct node_data, node);
+ bpf_rbtree_remove(&groot, &node_a->node);
+
+ return node_a->key < node_b->key;
+}
+
+static bool less__bad_fn_call_first_unlock_after(struct bpf_rb_node *a, const struct bpf_rb_node *b)
+{
+ struct node_data *node_a;
+ struct node_data *node_b;
+
+ node_a = container_of(a, struct node_data, node);
+ node_b = container_of(b, struct node_data, node);
+ bpf_rbtree_first(&groot);
+ bpf_spin_unlock(&glock);
+
+ return node_a->key < node_b->key;
+}
+
+static __always_inline
+long add_with_cb(bool (cb)(struct bpf_rb_node *a, const struct bpf_rb_node *b))
+{
+ struct node_data *n;
+
+ n = bpf_obj_new(typeof(*n));
+ if (!n)
+ return 1;
+
+ bpf_spin_lock(&glock);
+ bpf_rbtree_add(&groot, &n->node, cb);
+ bpf_spin_unlock(&glock);
+ return 0;
+}
+
+SEC("?tc")
+__failure __msg("arg#1 expected pointer to allocated object")
+long rbtree_api_add_bad_cb_bad_fn_call_add(void *ctx)
+{
+ return add_with_cb(less__bad_fn_call_add);
+}
+
+SEC("?tc")
+__failure __msg("rbtree_remove not allowed in rbtree cb")
+long rbtree_api_add_bad_cb_bad_fn_call_remove(void *ctx)
+{
+ return add_with_cb(less__bad_fn_call_remove);
+}
+
+SEC("?tc")
+__failure __msg("can't spin_{lock,unlock} in rbtree cb")
+long rbtree_api_add_bad_cb_bad_fn_call_first_unlock_after(void *ctx)
+{
+ return add_with_cb(less__bad_fn_call_first_unlock_after);
+}
+
+char _license[] SEC("license") = "GPL";