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, 48 insertions, 0 deletions

diff --git a/rust/helpers/barrier.c b/rust/helpers/barrier.c
new file mode 100644
index 000000000..dbc7a3017
--- /dev/null
+++ b/rust/helpers/barrier.c
@@ -0,0 +1,48 @@
+// SPDX-License-Identifier: GPL-2.0
+
+#include <asm/barrier.h>
+
+__rust_helper void rust_helper_mb(void)
+{
+	mb();
+}
+
+__rust_helper void rust_helper_rmb(void)
+{
+	rmb();
+}
+
+__rust_helper void rust_helper_wmb(void)
+{
+	wmb();
+}
+
+__rust_helper void rust_helper_dma_mb(void)
+{
+	dma_mb();
+}
+
+__rust_helper void rust_helper_dma_rmb(void)
+{
+	dma_rmb();
+}
+
+__rust_helper void rust_helper_dma_wmb(void)
+{
+	dma_wmb();
+}
+
+__rust_helper void rust_helper_smp_mb(void)
+{
+	smp_mb();
+}
+
+__rust_helper void rust_helper_smp_wmb(void)
+{
+	smp_wmb();
+}
+
+__rust_helper void rust_helper_smp_rmb(void)
+{
+	smp_rmb();
+}