From ba00369b20a3bf739bc91d48fda5720c7d38d448 Mon Sep 17 00:00:00 2001 From: Roman Gushchin Date: Thu, 5 Jul 2018 13:51:37 -0700 Subject: [PATCH] selftests/bpf: add verifier cgroup storage tests Add the following verifier tests to cover the cgroup storage functionality: 1) valid access to the cgroup storage 2) invalid access: use regular hashmap instead of cgroup storage map 3) invalid access: use invalid map fd 4) invalid access: try access memory after the cgroup storage 5) invalid access: try access memory before the cgroup storage 6) invalid access: call get_local_storage() with non-zero flags For tests 2)-6) check returned error strings. Expected output: $ ./test_verifier #0/u add+sub+mul OK #0/p add+sub+mul OK #1/u DIV32 by 0, zero check 1 OK ... #280/p valid cgroup storage access OK #281/p invalid cgroup storage access 1 OK #282/p invalid cgroup storage access 2 OK #283/p invalid per-cgroup storage access 3 OK #284/p invalid cgroup storage access 4 OK #285/p invalid cgroup storage access 5 OK ... #649/p pass modified ctx pointer to helper, 2 OK #650/p pass modified ctx pointer to helper, 3 OK Summary: 901 PASSED, 0 SKIPPED, 0 FAILED Signed-off-by: Roman Gushchin Cc: Alexei Starovoitov Cc: Daniel Borkmann Acked-by: Martin KaFai Lau --- tools/testing/selftests/bpf/bpf_helpers.h | 2 + tools/testing/selftests/bpf/test_verifier.c | 123 +++++++++++++++++++- 2 files changed, 124 insertions(+), 1 deletion(-) diff --git a/tools/testing/selftests/bpf/bpf_helpers.h b/tools/testing/selftests/bpf/bpf_helpers.h index f2f28b6c89151d..ccd959fd940e51 100644 --- a/tools/testing/selftests/bpf/bpf_helpers.h +++ b/tools/testing/selftests/bpf/bpf_helpers.h @@ -133,6 +133,8 @@ static int (*bpf_rc_keydown)(void *ctx, unsigned int protocol, (void *) BPF_FUNC_rc_keydown; static unsigned long long (*bpf_get_current_cgroup_id)(void) = (void *) BPF_FUNC_get_current_cgroup_id; +static void *(*bpf_get_local_storage)(void *map, unsigned long long flags) = + (void *) BPF_FUNC_get_local_storage; /* llvm builtin functions that eBPF C program may use to * emit BPF_LD_ABS and BPF_LD_IND instructions diff --git a/tools/testing/selftests/bpf/test_verifier.c b/tools/testing/selftests/bpf/test_verifier.c index 2ecd27b670d77e..7016fb2964a107 100644 --- a/tools/testing/selftests/bpf/test_verifier.c +++ b/tools/testing/selftests/bpf/test_verifier.c @@ -50,7 +50,7 @@ #define MAX_INSNS BPF_MAXINSNS #define MAX_FIXUPS 8 -#define MAX_NR_MAPS 7 +#define MAX_NR_MAPS 8 #define POINTER_VALUE 0xcafe4all #define TEST_DATA_LEN 64 @@ -70,6 +70,7 @@ struct bpf_test { int fixup_prog1[MAX_FIXUPS]; int fixup_prog2[MAX_FIXUPS]; int fixup_map_in_map[MAX_FIXUPS]; + int fixup_cgroup_storage[MAX_FIXUPS]; const char *errstr; const char *errstr_unpriv; uint32_t retval; @@ -4630,6 +4631,104 @@ static struct bpf_test tests[] = { .result = REJECT, .flags = F_NEEDS_EFFICIENT_UNALIGNED_ACCESS, }, + { + "valid cgroup storage access", + .insns = { + BPF_MOV64_IMM(BPF_REG_2, 0), + BPF_LD_MAP_FD(BPF_REG_1, 0), + BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, + BPF_FUNC_get_local_storage), + BPF_LDX_MEM(BPF_W, BPF_REG_1, BPF_REG_0, 0), + BPF_MOV64_REG(BPF_REG_0, BPF_REG_1), + BPF_ALU64_IMM(BPF_AND, BPF_REG_0, 1), + BPF_EXIT_INSN(), + }, + .fixup_cgroup_storage = { 1 }, + .result = ACCEPT, + .prog_type = BPF_PROG_TYPE_CGROUP_SKB, + }, + { + "invalid cgroup storage access 1", + .insns = { + BPF_MOV64_IMM(BPF_REG_2, 0), + BPF_LD_MAP_FD(BPF_REG_1, 0), + BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, + BPF_FUNC_get_local_storage), + BPF_LDX_MEM(BPF_W, BPF_REG_1, BPF_REG_0, 0), + BPF_MOV64_REG(BPF_REG_0, BPF_REG_1), + BPF_ALU64_IMM(BPF_AND, BPF_REG_0, 1), + BPF_EXIT_INSN(), + }, + .fixup_map1 = { 1 }, + .result = REJECT, + .errstr = "cannot pass map_type 1 into func bpf_get_local_storage", + .prog_type = BPF_PROG_TYPE_CGROUP_SKB, + }, + { + "invalid cgroup storage access 2", + .insns = { + BPF_MOV64_IMM(BPF_REG_2, 0), + BPF_LD_MAP_FD(BPF_REG_1, 1), + BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, + BPF_FUNC_get_local_storage), + BPF_ALU64_IMM(BPF_AND, BPF_REG_0, 1), + BPF_EXIT_INSN(), + }, + .result = REJECT, + .errstr = "fd 1 is not pointing to valid bpf_map", + .prog_type = BPF_PROG_TYPE_CGROUP_SKB, + }, + { + "invalid per-cgroup storage access 3", + .insns = { + BPF_MOV64_IMM(BPF_REG_2, 0), + BPF_LD_MAP_FD(BPF_REG_1, 0), + BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, + BPF_FUNC_get_local_storage), + BPF_LDX_MEM(BPF_W, BPF_REG_1, BPF_REG_0, 256), + BPF_ALU64_IMM(BPF_ADD, BPF_REG_1, 1), + BPF_MOV64_IMM(BPF_REG_0, 0), + BPF_EXIT_INSN(), + }, + .fixup_cgroup_storage = { 1 }, + .result = REJECT, + .errstr = "invalid access to map value, value_size=64 off=256 size=4", + .prog_type = BPF_PROG_TYPE_CGROUP_SKB, + }, + { + "invalid cgroup storage access 4", + .insns = { + BPF_MOV64_IMM(BPF_REG_2, 0), + BPF_LD_MAP_FD(BPF_REG_1, 0), + BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, + BPF_FUNC_get_local_storage), + BPF_LDX_MEM(BPF_W, BPF_REG_1, BPF_REG_0, -2), + BPF_MOV64_REG(BPF_REG_0, BPF_REG_1), + BPF_ALU64_IMM(BPF_ADD, BPF_REG_1, 1), + BPF_EXIT_INSN(), + }, + .fixup_cgroup_storage = { 1 }, + .result = REJECT, + .errstr = "invalid access to map value, value_size=64 off=-2 size=4", + .prog_type = BPF_PROG_TYPE_CGROUP_SKB, + }, + { + "invalid cgroup storage access 5", + .insns = { + BPF_MOV64_IMM(BPF_REG_2, 7), + BPF_LD_MAP_FD(BPF_REG_1, 0), + BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, + BPF_FUNC_get_local_storage), + BPF_LDX_MEM(BPF_W, BPF_REG_1, BPF_REG_0, 0), + BPF_MOV64_REG(BPF_REG_0, BPF_REG_1), + BPF_ALU64_IMM(BPF_AND, BPF_REG_0, 1), + BPF_EXIT_INSN(), + }, + .fixup_cgroup_storage = { 1 }, + .result = REJECT, + .errstr = "get_local_storage() doesn't support non-zero flags", + .prog_type = BPF_PROG_TYPE_CGROUP_SKB, + }, { "multiple registers share map_lookup_elem result", .insns = { @@ -12418,6 +12517,19 @@ static int create_map_in_map(void) return outer_map_fd; } +static int create_cgroup_storage(void) +{ + int fd; + + fd = bpf_create_map(BPF_MAP_TYPE_CGROUP_STORAGE, + sizeof(struct bpf_cgroup_storage_key), + TEST_DATA_LEN, 0, 0); + if (fd < 0) + printf("Failed to create array '%s'!\n", strerror(errno)); + + return fd; +} + static char bpf_vlog[UINT_MAX >> 8]; static void do_test_fixup(struct bpf_test *test, struct bpf_insn *prog, @@ -12430,6 +12542,7 @@ static void do_test_fixup(struct bpf_test *test, struct bpf_insn *prog, int *fixup_prog1 = test->fixup_prog1; int *fixup_prog2 = test->fixup_prog2; int *fixup_map_in_map = test->fixup_map_in_map; + int *fixup_cgroup_storage = test->fixup_cgroup_storage; if (test->fill_helper) test->fill_helper(test); @@ -12497,6 +12610,14 @@ static void do_test_fixup(struct bpf_test *test, struct bpf_insn *prog, fixup_map_in_map++; } while (*fixup_map_in_map); } + + if (*fixup_cgroup_storage) { + map_fds[7] = create_cgroup_storage(); + do { + prog[*fixup_cgroup_storage].imm = map_fds[7]; + fixup_cgroup_storage++; + } while (*fixup_cgroup_storage); + } } static void do_test_single(struct bpf_test *test, bool unpriv,