From: John Fastabend <john.fastabend@xxxxxxxxx> commit cf66c29bd7534813d2e1971fab71e25fe87c7e0a upstream Added a verifier test for assigning 32bit reg states to 64bit where 32bit reg holds a constant value of 0. Without previous kernel verifier.c fix, the test in this patch will fail. Signed-off-by: Yonghong Song <yhs@xxxxxx> Signed-off-by: John Fastabend <john.fastabend@xxxxxxxxx> Signed-off-by: Alexei Starovoitov <ast@xxxxxxxxxx> Link: https://lore.kernel.org/bpf/159077335867.6014.2075350327073125374.stgit@john-Precision-5820-Tower Signed-off-by: Ovidiu Panait <ovidiu.panait@xxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- tools/testing/selftests/bpf/verifier/bounds.c | 22 ++++++++++++++++++++++ 1 file changed, 22 insertions(+) --- a/tools/testing/selftests/bpf/verifier/bounds.c +++ b/tools/testing/selftests/bpf/verifier/bounds.c @@ -545,3 +545,25 @@ }, .result = ACCEPT }, +{ + "assigning 32bit bounds to 64bit for wA = 0, wB = wA", + .insns = { + BPF_LDX_MEM(BPF_W, BPF_REG_8, BPF_REG_1, + offsetof(struct __sk_buff, data_end)), + BPF_LDX_MEM(BPF_W, BPF_REG_7, BPF_REG_1, + offsetof(struct __sk_buff, data)), + BPF_MOV32_IMM(BPF_REG_9, 0), + BPF_MOV32_REG(BPF_REG_2, BPF_REG_9), + BPF_MOV64_REG(BPF_REG_6, BPF_REG_7), + BPF_ALU64_REG(BPF_ADD, BPF_REG_6, BPF_REG_2), + BPF_MOV64_REG(BPF_REG_3, BPF_REG_6), + BPF_ALU64_IMM(BPF_ADD, BPF_REG_3, 8), + BPF_JMP_REG(BPF_JGT, BPF_REG_3, BPF_REG_8, 1), + BPF_LDX_MEM(BPF_W, BPF_REG_5, BPF_REG_6, 0), + BPF_MOV64_IMM(BPF_REG_0, 0), + BPF_EXIT_INSN(), + }, + .prog_type = BPF_PROG_TYPE_SCHED_CLS, + .result = ACCEPT, + .flags = F_NEEDS_EFFICIENT_UNALIGNED_ACCESS, +},