18b8926557
Verify that the following example is rejected by verifier: r9 = ... some pointer with range X ... r6 = ... unbound scalar ID=a ... r7 = ... unbound scalar ID=b ... if (r6 > r7) goto +1 r7 = r6 if (r7 > X) goto exit r9 += r6 *(u64 *)r9 = Y Also add test cases to: - check that check_alu_op() for BPF_MOV instruction does not allocate scalar ID if source register is a constant; - check that unique scalar IDs are ignored when new verifier state is compared to cached verifier state; - check that two different scalar IDs in a verified state can't be mapped to the same scalar ID in current state. Signed-off-by: Eduard Zingerman <eddyz87@gmail.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/20230613153824.3324830-5-eddyz87@gmail.com