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authorDmitry Torokhov <dmitry.torokhov@gmail.com>2023-08-30 16:06:38 -0700
committerDmitry Torokhov <dmitry.torokhov@gmail.com>2023-08-30 16:06:38 -0700
commit1ac731c529cd4d6adbce134754b51ff7d822b145 (patch)
tree143ab3f35ca5f3b69f583c84e6964b17139c2ec1 /kernel/bpf/bpf_iter.c
parent07b4c950f27bef0362dc6ad7ee713aab61d58149 (diff)
parent54116d442e001e1b6bd482122043b1870998a1f3 (diff)
Merge branch 'next' into for-linus
Prepare input updates for 6.6 merge window.
Diffstat (limited to 'kernel/bpf/bpf_iter.c')
-rw-r--r--kernel/bpf/bpf_iter.c70
1 files changed, 70 insertions, 0 deletions
diff --git a/kernel/bpf/bpf_iter.c b/kernel/bpf/bpf_iter.c
index 5dc307bdeaeb..96856f130cbf 100644
--- a/kernel/bpf/bpf_iter.c
+++ b/kernel/bpf/bpf_iter.c
@@ -776,3 +776,73 @@ const struct bpf_func_proto bpf_loop_proto = {
.arg3_type = ARG_PTR_TO_STACK_OR_NULL,
.arg4_type = ARG_ANYTHING,
};
+
+struct bpf_iter_num_kern {
+ int cur; /* current value, inclusive */
+ int end; /* final value, exclusive */
+} __aligned(8);
+
+__diag_push();
+__diag_ignore_all("-Wmissing-prototypes",
+ "Global functions as their definitions will be in vmlinux BTF");
+
+__bpf_kfunc int bpf_iter_num_new(struct bpf_iter_num *it, int start, int end)
+{
+ struct bpf_iter_num_kern *s = (void *)it;
+
+ BUILD_BUG_ON(sizeof(struct bpf_iter_num_kern) != sizeof(struct bpf_iter_num));
+ BUILD_BUG_ON(__alignof__(struct bpf_iter_num_kern) != __alignof__(struct bpf_iter_num));
+
+ BTF_TYPE_EMIT(struct btf_iter_num);
+
+ /* start == end is legit, it's an empty range and we'll just get NULL
+ * on first (and any subsequent) bpf_iter_num_next() call
+ */
+ if (start > end) {
+ s->cur = s->end = 0;
+ return -EINVAL;
+ }
+
+ /* avoid overflows, e.g., if start == INT_MIN and end == INT_MAX */
+ if ((s64)end - (s64)start > BPF_MAX_LOOPS) {
+ s->cur = s->end = 0;
+ return -E2BIG;
+ }
+
+ /* user will call bpf_iter_num_next() first,
+ * which will set s->cur to exactly start value;
+ * underflow shouldn't matter
+ */
+ s->cur = start - 1;
+ s->end = end;
+
+ return 0;
+}
+
+__bpf_kfunc int *bpf_iter_num_next(struct bpf_iter_num* it)
+{
+ struct bpf_iter_num_kern *s = (void *)it;
+
+ /* check failed initialization or if we are done (same behavior);
+ * need to be careful about overflow, so convert to s64 for checks,
+ * e.g., if s->cur == s->end == INT_MAX, we can't just do
+ * s->cur + 1 >= s->end
+ */
+ if ((s64)(s->cur + 1) >= s->end) {
+ s->cur = s->end = 0;
+ return NULL;
+ }
+
+ s->cur++;
+
+ return &s->cur;
+}
+
+__bpf_kfunc void bpf_iter_num_destroy(struct bpf_iter_num *it)
+{
+ struct bpf_iter_num_kern *s = (void *)it;
+
+ s->cur = s->end = 0;
+}
+
+__diag_pop();