From 0869e5078afbd1b22c20832b391b2d85291bc0a8 Mon Sep 17 00:00:00 2001 From: Alexei Starovoitov Date: Mon, 1 Nov 2021 15:21:53 -0700 Subject: selftests/bpf: Add a testcase for 64-bit bounds propagation issue. ./test_progs-no_alu32 -vv -t twfw Before the 64-bit_into_32-bit fix: 19: (25) if r1 > 0x3f goto pc+6 R1_w=inv(id=0,umax_value=63,var_off=(0x0; 0xff),s32_max_value=255,u32_max_value=255) and eventually: invalid access to map value, value_size=8 off=7 size=8 R6 max value is outside of the allowed memory range libbpf: failed to load object 'no_alu32/twfw.o' After the fix: 19: (25) if r1 > 0x3f goto pc+6 R1_w=inv(id=0,umax_value=63,var_off=(0x0; 0x3f)) verif_twfw:OK Signed-off-by: Alexei Starovoitov Signed-off-by: Andrii Nakryiko Acked-by: Yonghong Song Link: https://lore.kernel.org/bpf/20211101222153.78759-3-alexei.starovoitov@gmail.com --- .../selftests/bpf/prog_tests/bpf_verif_scale.c | 5 ++ tools/testing/selftests/bpf/progs/twfw.c | 58 ++++++++++++++++++++++ 2 files changed, 63 insertions(+) create mode 100644 tools/testing/selftests/bpf/progs/twfw.c (limited to 'tools/testing') diff --git a/tools/testing/selftests/bpf/prog_tests/bpf_verif_scale.c b/tools/testing/selftests/bpf/prog_tests/bpf_verif_scale.c index 867349e4ed9e..27f5d8ea7964 100644 --- a/tools/testing/selftests/bpf/prog_tests/bpf_verif_scale.c +++ b/tools/testing/selftests/bpf/prog_tests/bpf_verif_scale.c @@ -202,3 +202,8 @@ void test_verif_scale_seg6_loop() { scale_test("test_seg6_loop.o", BPF_PROG_TYPE_LWT_SEG6LOCAL, false); } + +void test_verif_twfw() +{ + scale_test("twfw.o", BPF_PROG_TYPE_CGROUP_SKB, false); +} diff --git a/tools/testing/selftests/bpf/progs/twfw.c b/tools/testing/selftests/bpf/progs/twfw.c new file mode 100644 index 000000000000..de1b18a62b46 --- /dev/null +++ b/tools/testing/selftests/bpf/progs/twfw.c @@ -0,0 +1,58 @@ +// SPDX-License-Identifier: GPL-2.0 +/* Copyright (c) 2021 Facebook */ +#include +#include +#include +#include + +#define TWFW_MAX_TIERS (64) +/* + * load is successful + * #define TWFW_MAX_TIERS (64u)$ + */ + +struct twfw_tier_value { + unsigned long mask[1]; +}; + +struct rule { + uint8_t seqnum; +}; + +struct rules_map { + __uint(type, BPF_MAP_TYPE_ARRAY); + __type(key, __u32); + __type(value, struct rule); + __uint(max_entries, 1); +}; + +struct tiers_map { + __uint(type, BPF_MAP_TYPE_ARRAY); + __type(key, __u32); + __type(value, struct twfw_tier_value); + __uint(max_entries, 1); +}; + +struct rules_map rules SEC(".maps"); +struct tiers_map tiers SEC(".maps"); + +SEC("cgroup_skb/ingress") +int twfw_verifier(struct __sk_buff* skb) +{ + const uint32_t key = 0; + const struct twfw_tier_value* tier = bpf_map_lookup_elem(&tiers, &key); + if (!tier) + return 1; + + struct rule* rule = bpf_map_lookup_elem(&rules, &key); + if (!rule) + return 1; + + if (rule && rule->seqnum < TWFW_MAX_TIERS) { + /* rule->seqnum / 64 should always be 0 */ + unsigned long mask = tier->mask[rule->seqnum / 64]; + if (mask) + return 0; + } + return 1; +} -- cgit