From: Aaron Yue <haoxu...@fb.com>
test various corner cases of the helper function access to the packet
via crafted XDP programs.
Signed-off-by: Aaron Yue <haoxu...@fb.com>
Signed-off-by: Alexei Starovoitov <a...@kernel.org>
Acked-by: Daniel Borkmann <dan...@iogearbox.net>
---
samples/bpf/test_verifier.c | 114 ++++++++++++++++++++++++++++++++++++++++++--
1 file changed, 110 insertions(+), 4 deletions(-)
diff --git a/samples/bpf/test_verifier.c b/samples/bpf/test_verifier.c
index fe2fcec98c1f..78c6f131d94f 100644
--- a/samples/bpf/test_verifier.c
+++ b/samples/bpf/test_verifier.c
@@ -1449,7 +1449,7 @@ static struct bpf_test tests[] = {
.prog_type = BPF_PROG_TYPE_SCHED_CLS,
},
{
- "pkt: test1",
+ "direct packet access: test1",
.insns = {
BPF_LDX_MEM(BPF_W, BPF_REG_2, BPF_REG_1,
offsetof(struct __sk_buff, data)),
@@ -1466,7 +1466,7 @@ static struct bpf_test tests[] = {
.prog_type = BPF_PROG_TYPE_SCHED_CLS,
},
{
- "pkt: test2",
+ "direct packet access: test2",
.insns = {
BPF_MOV64_IMM(BPF_REG_0, 1),
BPF_LDX_MEM(BPF_W, BPF_REG_4, BPF_REG_1,
@@ -1499,7 +1499,7 @@ static struct bpf_test tests[] = {
.prog_type = BPF_PROG_TYPE_SCHED_CLS,
},
{
- "pkt: test3",
+ "direct packet access: test3",
.insns = {
BPF_LDX_MEM(BPF_W, BPF_REG_2, BPF_REG_1,
offsetof(struct __sk_buff, data)),
@@ -1511,7 +1511,7 @@ static struct bpf_test tests[] = {
.prog_type = BPF_PROG_TYPE_SOCKET_FILTER,
},
{
- "pkt: test4",
+ "direct packet access: test4",
.insns = {
BPF_LDX_MEM(BPF_W, BPF_REG_2, BPF_REG_1,
offsetof(struct __sk_buff, data)),
@@ -1528,6 +1528,112 @@ static struct bpf_test tests[] = {
.result = REJECT,
.prog_type = BPF_PROG_TYPE_SCHED_CLS,
},
+ {
+ "helper access to packet: test1, valid packet_ptr range",
+ .insns = {
+ BPF_LDX_MEM(BPF_W, BPF_REG_2, BPF_REG_1,
+ offsetof(struct xdp_md, data)),
+ BPF_LDX_MEM(BPF_W, BPF_REG_3, BPF_REG_1,
+ offsetof(struct xdp_md, data_end)),
+ BPF_MOV64_REG(BPF_REG_1, BPF_REG_2),
+ BPF_ALU64_IMM(BPF_ADD, BPF_REG_1, 8),
+ BPF_JMP_REG(BPF_JGT, BPF_REG_1, BPF_REG_3, 5),
+ BPF_LD_MAP_FD(BPF_REG_1, 0),
+ BPF_MOV64_REG(BPF_REG_3, BPF_REG_2),
+ BPF_MOV64_IMM(BPF_REG_4, 0),
+ BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0,
BPF_FUNC_map_update_elem),
+ BPF_MOV64_IMM(BPF_REG_0, 0),
+ BPF_EXIT_INSN(),
+ },
+ .fixup = {5},
+ .result_unpriv = ACCEPT,
+ .result = ACCEPT,
+ .prog_type = BPF_PROG_TYPE_XDP,
+ },
+ {
+ "helper access to packet: test2, unchecked packet_ptr",
+ .insns = {
+ BPF_LDX_MEM(BPF_W, BPF_REG_2, BPF_REG_1,
+ offsetof(struct xdp_md, data)),
+ BPF_LD_MAP_FD(BPF_REG_1, 0),
+ BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0,
BPF_FUNC_map_lookup_elem),
+ BPF_MOV64_IMM(BPF_REG_0, 0),
+ BPF_EXIT_INSN(),
+ },
+ .fixup = {1},
+ .result = REJECT,
+ .errstr = "invalid access to packet",
+ .prog_type = BPF_PROG_TYPE_XDP,
+ },
+ {
+ "helper access to packet: test3, variable add",
+ .insns = {
+ BPF_LDX_MEM(BPF_W, BPF_REG_2, BPF_REG_1,
+ offsetof(struct xdp_md, data)),
+ BPF_LDX_MEM(BPF_W, BPF_REG_3, BPF_REG_1,
+ offsetof(struct xdp_md, data_end)),
+ BPF_MOV64_REG(BPF_REG_4, BPF_REG_2),
+ BPF_ALU64_IMM(BPF_ADD, BPF_REG_4, 8),
+ BPF_JMP_REG(BPF_JGT, BPF_REG_4, BPF_REG_3, 10),
+ BPF_LDX_MEM(BPF_B, BPF_REG_5, BPF_REG_2, 0),
+ BPF_MOV64_REG(BPF_REG_4, BPF_REG_2),
+ BPF_ALU64_REG(BPF_ADD, BPF_REG_4, BPF_REG_5),
+ BPF_MOV64_REG(BPF_REG_5, BPF_REG_4),
+ BPF_ALU64_IMM(BPF_ADD, BPF_REG_5, 8),
+ BPF_JMP_REG(BPF_JGT, BPF_REG_5, BPF_REG_3, 4),
+ BPF_LD_MAP_FD(BPF_REG_1, 0),
+ BPF_MOV64_REG(BPF_REG_2, BPF_REG_4),
+ BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0,
BPF_FUNC_map_lookup_elem),
+ BPF_MOV64_IMM(BPF_REG_0, 0),
+ BPF_EXIT_INSN(),
+ },
+ .fixup = {11},
+ .result = ACCEPT,
+ .prog_type = BPF_PROG_TYPE_XDP,
+ },
+ {
+ "helper access to packet: test4, packet_ptr with bad range",
+ .insns = {
+ BPF_LDX_MEM(BPF_W, BPF_REG_2, BPF_REG_1,
+ offsetof(struct xdp_md, data)),
+ BPF_LDX_MEM(BPF_W, BPF_REG_3, BPF_REG_1,
+ offsetof(struct xdp_md, data_end)),
+ BPF_MOV64_REG(BPF_REG_4, BPF_REG_2),
+ BPF_ALU64_IMM(BPF_ADD, BPF_REG_4, 4),
+ BPF_JMP_REG(BPF_JGT, BPF_REG_4, BPF_REG_3, 2),
+ BPF_MOV64_IMM(BPF_REG_0, 0),
+ BPF_EXIT_INSN(),
+ BPF_LD_MAP_FD(BPF_REG_1, 0),
+ BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0,
BPF_FUNC_map_lookup_elem),
+ BPF_MOV64_IMM(BPF_REG_0, 0),
+ BPF_EXIT_INSN(),
+ },
+ .fixup = {7},
+ .result = REJECT,
+ .errstr = "invalid access to packet",
+ .prog_type = BPF_PROG_TYPE_XDP,
+ },
+ {
+ "helper access to packet: test5, packet_ptr with too short
range",
+ .insns = {
+ BPF_LDX_MEM(BPF_W, BPF_REG_2, BPF_REG_1,
+ offsetof(struct xdp_md, data)),
+ BPF_LDX_MEM(BPF_W, BPF_REG_3, BPF_REG_1,
+ offsetof(struct xdp_md, data_end)),
+ BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, 1),
+ BPF_MOV64_REG(BPF_REG_4, BPF_REG_2),
+ BPF_ALU64_IMM(BPF_ADD, BPF_REG_4, 7),
+ BPF_JMP_REG(BPF_JGT, BPF_REG_4, BPF_REG_3, 3),
+ BPF_LD_MAP_FD(BPF_REG_1, 0),
+ BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0,
BPF_FUNC_map_lookup_elem),
+ BPF_MOV64_IMM(BPF_REG_0, 0),
+ BPF_EXIT_INSN(),
+ },
+ .fixup = {6},
+ .result = REJECT,
+ .errstr = "invalid access to packet",
+ .prog_type = BPF_PROG_TYPE_XDP,
+ },
};
static int probe_filter_length(struct bpf_insn *fp)
--
2.8.0
