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|
{
"context stores via ST",
.insns = {
BPF_MOV64_IMM(BPF_REG_0, 0),
BPF_ST_MEM(BPF_DW, BPF_REG_1, offsetof(struct __sk_buff, mark), 0),
BPF_EXIT_INSN(),
},
.errstr = "BPF_ST stores into R1 ctx is not allowed",
.result = REJECT,
.prog_type = BPF_PROG_TYPE_SCHED_CLS,
},
{
"context stores via BPF_ATOMIC",
.insns = {
BPF_MOV64_IMM(BPF_REG_0, 0),
BPF_ATOMIC_OP(BPF_W, BPF_ADD, BPF_REG_1, BPF_REG_0, offsetof(struct __sk_buff, mark)),
BPF_EXIT_INSN(),
},
.errstr = "BPF_ATOMIC stores into R1 ctx is not allowed",
.result = REJECT,
.prog_type = BPF_PROG_TYPE_SCHED_CLS,
},
{
"arithmetic ops make PTR_TO_CTX unusable",
.insns = {
BPF_ALU64_IMM(BPF_ADD, BPF_REG_1,
offsetof(struct __sk_buff, data) -
offsetof(struct __sk_buff, mark)),
BPF_LDX_MEM(BPF_W, BPF_REG_0, BPF_REG_1,
offsetof(struct __sk_buff, mark)),
BPF_EXIT_INSN(),
},
.errstr = "dereference of modified ctx ptr",
.result = REJECT,
.prog_type = BPF_PROG_TYPE_SCHED_CLS,
},
{
"pass unmodified ctx pointer to helper",
.insns = {
BPF_MOV64_IMM(BPF_REG_2, 0),
BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0,
BPF_FUNC_csum_update),
BPF_MOV64_IMM(BPF_REG_0, 0),
BPF_EXIT_INSN(),
},
.prog_type = BPF_PROG_TYPE_SCHED_CLS,
.result = ACCEPT,
},
{
"pass modified ctx pointer to helper, 1",
.insns = {
BPF_ALU64_IMM(BPF_ADD, BPF_REG_1, -612),
BPF_MOV64_IMM(BPF_REG_2, 0),
BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0,
BPF_FUNC_csum_update),
BPF_MOV64_IMM(BPF_REG_0, 0),
BPF_EXIT_INSN(),
},
.prog_type = BPF_PROG_TYPE_SCHED_CLS,
.result = REJECT,
.errstr = "negative offset ctx ptr R1 off=-612 disallowed",
},
{
"pass modified ctx pointer to helper, 2",
.insns = {
BPF_ALU64_IMM(BPF_ADD, BPF_REG_1, -612),
BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0,
BPF_FUNC_get_socket_cookie),
BPF_MOV64_IMM(BPF_REG_0, 0),
BPF_EXIT_INSN(),
},
.result_unpriv = REJECT,
.result = REJECT,
.errstr_unpriv = "negative offset ctx ptr R1 off=-612 disallowed",
.errstr = "negative offset ctx ptr R1 off=-612 disallowed",
},
{
"pass modified ctx pointer to helper, 3",
.insns = {
BPF_LDX_MEM(BPF_W, BPF_REG_3, BPF_REG_1, 0),
BPF_ALU64_IMM(BPF_AND, BPF_REG_3, 4),
BPF_ALU64_REG(BPF_ADD, BPF_REG_1, BPF_REG_3),
BPF_MOV64_IMM(BPF_REG_2, 0),
BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0,
BPF_FUNC_csum_update),
BPF_MOV64_IMM(BPF_REG_0, 0),
BPF_EXIT_INSN(),
},
.prog_type = BPF_PROG_TYPE_SCHED_CLS,
.result = REJECT,
.errstr = "variable ctx access var_off=(0x0; 0x4)",
},
{
"pass ctx or null check, 1: ctx",
.insns = {
BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0,
BPF_FUNC_get_netns_cookie),
BPF_MOV64_IMM(BPF_REG_0, 0),
BPF_EXIT_INSN(),
},
.prog_type = BPF_PROG_TYPE_CGROUP_SOCK_ADDR,
.expected_attach_type = BPF_CGROUP_UDP6_SENDMSG,
.result = ACCEPT,
},
{
"pass ctx or null check, 2: null",
.insns = {
BPF_MOV64_IMM(BPF_REG_1, 0),
BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0,
BPF_FUNC_get_netns_cookie),
BPF_MOV64_IMM(BPF_REG_0, 0),
BPF_EXIT_INSN(),
},
.prog_type = BPF_PROG_TYPE_CGROUP_SOCK_ADDR,
.expected_attach_type = BPF_CGROUP_UDP6_SENDMSG,
.result = ACCEPT,
},
{
"pass ctx or null check, 3: 1",
.insns = {
BPF_MOV64_IMM(BPF_REG_1, 1),
BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0,
BPF_FUNC_get_netns_cookie),
BPF_MOV64_IMM(BPF_REG_0, 0),
BPF_EXIT_INSN(),
},
.prog_type = BPF_PROG_TYPE_CGROUP_SOCK_ADDR,
.expected_attach_type = BPF_CGROUP_UDP6_SENDMSG,
.result = REJECT,
.errstr = "R1 type=scalar expected=ctx",
},
{
"pass ctx or null check, 4: ctx - const",
.insns = {
BPF_ALU64_IMM(BPF_ADD, BPF_REG_1, -612),
BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0,
BPF_FUNC_get_netns_cookie),
BPF_MOV64_IMM(BPF_REG_0, 0),
BPF_EXIT_INSN(),
},
.prog_type = BPF_PROG_TYPE_CGROUP_SOCK_ADDR,
.expected_attach_type = BPF_CGROUP_UDP6_SENDMSG,
.result = REJECT,
.errstr = "negative offset ctx ptr R1 off=-612 disallowed",
},
{
"pass ctx or null check, 5: null (connect)",
.insns = {
BPF_MOV64_IMM(BPF_REG_1, 0),
BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0,
BPF_FUNC_get_netns_cookie),
BPF_MOV64_IMM(BPF_REG_0, 0),
BPF_EXIT_INSN(),
},
.prog_type = BPF_PROG_TYPE_CGROUP_SOCK_ADDR,
.expected_attach_type = BPF_CGROUP_INET4_CONNECT,
.result = ACCEPT,
},
{
"pass ctx or null check, 6: null (bind)",
.insns = {
BPF_MOV64_IMM(BPF_REG_1, 0),
BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0,
BPF_FUNC_get_netns_cookie),
BPF_MOV64_IMM(BPF_REG_0, 0),
BPF_EXIT_INSN(),
},
.prog_type = BPF_PROG_TYPE_CGROUP_SOCK,
.expected_attach_type = BPF_CGROUP_INET4_POST_BIND,
.result = ACCEPT,
},
{
"pass ctx or null check, 7: ctx (bind)",
.insns = {
BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0,
BPF_FUNC_get_socket_cookie),
BPF_MOV64_IMM(BPF_REG_0, 0),
BPF_EXIT_INSN(),
},
.prog_type = BPF_PROG_TYPE_CGROUP_SOCK,
.expected_attach_type = BPF_CGROUP_INET4_POST_BIND,
.result = ACCEPT,
},
{
"pass ctx or null check, 8: null (bind)",
.insns = {
BPF_MOV64_IMM(BPF_REG_1, 0),
BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0,
BPF_FUNC_get_socket_cookie),
BPF_MOV64_IMM(BPF_REG_0, 0),
BPF_EXIT_INSN(),
},
.prog_type = BPF_PROG_TYPE_CGROUP_SOCK,
.expected_attach_type = BPF_CGROUP_INET4_POST_BIND,
.result = REJECT,
.errstr = "R1 type=scalar expected=ctx",
},
|
