Commit 23599ada authored by Daniel Borkmann's avatar Daniel Borkmann Committed by Alexei Starovoitov
Browse files

bpf: Add selftest cases for ctx_or_null argument type 



Add various tests to make sure the verifier keeps catching them:

  # ./test_verifier
  [...]
  #230/p pass ctx or null check, 1: ctx OK
  #231/p pass ctx or null check, 2: null OK
  #232/p pass ctx or null check, 3: 1 OK
  #233/p pass ctx or null check, 4: ctx - const OK
  #234/p pass ctx or null check, 5: null (connect) OK
  #235/p pass ctx or null check, 6: null (bind) OK
  #236/p pass ctx or null check, 7: ctx (bind) OK
  #237/p pass ctx or null check, 8: null (bind) OK
  [...]
  Summary: 1595 PASSED, 0 SKIPPED, 0 FAILED

Signed-off-by: default avatarDaniel Borkmann <daniel@iogearbox.net>
Signed-off-by: default avatarAlexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/c74758d07b1b678036465ef7f068a49e9efd3548.1585323121.git.daniel@iogearbox.net
parent 834ebca8

tools/testing/selftests/bpf/verifier/ctx.c

+105 −0
Original line number Diff line number Diff line
@@ -91,3 +91,108 @@ 
	.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=inv 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 = "dereference of modified ctx ptr",

},

{

	"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=inv expected=ctx",

},

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