selftests/bpf: Check that JMP32 pointer vs zero jumps are not predictedgrafted

Add jmp32_ptr_vs_zero_jne: the fall-through of the 32-bit compare, which
the verifier used to skip, contains an out of bounds map value access,
hence w/o the previous patch the program is accepted. See previous patch
for detailed description.

Reported-by: Nicholas Carlini <npc@anthropic.com>
Suggested-by: Nicholas Carlini <npc@anthropic.com>
Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
Link: https://lore.kernel.org/bpf/20260904083325.2083493-6-eddyz87@gmail.com
Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>

1 files changed, 28 insertions, 0 deletions

diff --git a/rust/helpers/page.c b/rust/helpers/page.c
new file mode 100644
index 000000000..f8463fbed
--- /dev/null
+++ b/rust/helpers/page.c
@@ -0,0 +1,28 @@
+// SPDX-License-Identifier: GPL-2.0
+
+#include <linux/gfp.h>
+#include <linux/highmem.h>
+#include <linux/mm.h>
+
+__rust_helper struct page *rust_helper_alloc_pages(gfp_t gfp_mask,
+						   unsigned int order)
+{
+	return alloc_pages(gfp_mask, order);
+}
+
+__rust_helper void *rust_helper_kmap_local_page(struct page *page)
+{
+	return kmap_local_page(page);
+}
+
+__rust_helper void rust_helper_kunmap_local(const void *addr)
+{
+	kunmap_local(addr);
+}
+
+#ifndef NODE_NOT_IN_PAGE_FLAGS
+__rust_helper int rust_helper_page_to_nid(const struct page *page)
+{
+	return page_to_nid(page);
+}
+#endif