Skip to content

Commit

Permalink
selftests/bpf: Add verifier tests for bpf arg ARG_CONST_MAP_PTR_OR_NULL
Browse files Browse the repository at this point in the history 
Use helper bpf_redirect_map() and bpf_redirect_map_multi() to test bpf
arg ARG_CONST_MAP_PTR and ARG_CONST_MAP_PTR_OR_NULL. Make sure the
map arg could be verified correctly when it is NULL or valid map
pointer.

Add devmap and devmap_hash in struct bpf_test due to bpf_redirect_{map,
map_multi} limit.

Test result:
 ]# ./test_verifier 713 716
 torvalds#713/p ARG_CONST_MAP_PTR: null pointer OK
 torvalds#714/p ARG_CONST_MAP_PTR: valid map pointer OK
 torvalds#715/p ARG_CONST_MAP_PTR_OR_NULL: null pointer for ex_map OK
 torvalds#716/p ARG_CONST_MAP_PTR_OR_NULL: valid map pointer for ex_map OK
 Summary: 4 PASSED, 0 SKIPPED, 0 FAILED

Signed-off-by: Hangbin Liu <liuhangbin@gmail.com>
  • Loading branch information
@liuhangbin @intel-lab-lkp
liuhangbin authored and intel-lab-lkp committed Jan 20, 2021
1 parent 58a5467 commit 650db55
Show file tree
Hide file tree
Showing 2 changed files with 91 additions and 1 deletion.
22 changes: 21 additions & 1 deletion tools/testing/selftests/bpf/test_verifier.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -50,7 +50,7 @@
#define MAX_INSNS BPF_MAXINSNS
#define MAX_TEST_INSNS 1000000
#define MAX_FIXUPS 8
#define MAX_NR_MAPS 20
#define MAX_NR_MAPS 22
#define MAX_TEST_RUNS 8
#define POINTER_VALUE 0xcafe4all
#define TEST_DATA_LEN 64
Expand Down Expand Up @@ -87,6 +87,8 @@ struct bpf_test {
int fixup_sk_storage_map[MAX_FIXUPS];
int fixup_map_event_output[MAX_FIXUPS];
int fixup_map_reuseport_array[MAX_FIXUPS];
int fixup_map_devmap[MAX_FIXUPS];
int fixup_map_devmap_hash[MAX_FIXUPS];
const char *errstr;
const char *errstr_unpriv;
uint32_t insn_processed;
Expand Down Expand Up @@ -712,6 +714,8 @@ static void do_test_fixup(struct bpf_test *test, enum bpf_prog_type prog_type,
int *fixup_sk_storage_map = test->fixup_sk_storage_map;
int *fixup_map_event_output = test->fixup_map_event_output;
int *fixup_map_reuseport_array = test->fixup_map_reuseport_array;
int *fixup_map_devmap = test->fixup_map_devmap;
int *fixup_map_devmap_hash = test->fixup_map_devmap_hash;

if (test->fill_helper) {
test->fill_insns = calloc(MAX_TEST_INSNS, sizeof(struct bpf_insn));
Expand Down Expand Up @@ -889,6 +893,22 @@ static void do_test_fixup(struct bpf_test *test, enum bpf_prog_type prog_type,
fixup_map_reuseport_array++;
} while (*fixup_map_reuseport_array);
}
if (*fixup_map_devmap) {
map_fds[20] = __create_map(BPF_MAP_TYPE_DEVMAP,
sizeof(u32), sizeof(u32), 1, 0);
do {
prog[*fixup_map_devmap].imm = map_fds[20];
fixup_map_devmap++;
} while (*fixup_map_devmap);
}
if (*fixup_map_devmap_hash) {
map_fds[21] = __create_map(BPF_MAP_TYPE_DEVMAP_HASH,
sizeof(u32), sizeof(u32), 1, 0);
do {
prog[*fixup_map_devmap_hash].imm = map_fds[21];
fixup_map_devmap_hash++;
} while (*fixup_map_devmap_hash);
}
}

struct libcap {
Expand Down
70 changes: 70 additions & 0 deletions tools/testing/selftests/bpf/verifier/map_ptr.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -93,3 +93,73 @@
.fixup_map_hash_16b = { 4 },
.result = ACCEPT,
},
{
"ARG_CONST_MAP_PTR: null pointer",
.insns = {
/* bpf_redirect_map arg1 (map) */
BPF_MOV64_IMM(BPF_REG_1, 0),
/* bpf_redirect_map arg2 (ifindex) */
BPF_MOV64_IMM(BPF_REG_2, 0),
/* bpf_redirect_map arg3 (flags) */
BPF_MOV64_IMM(BPF_REG_3, 0),
BPF_EMIT_CALL(BPF_FUNC_redirect_map),
BPF_EXIT_INSN(),
},
.result = REJECT,
.prog_type = BPF_PROG_TYPE_XDP,
.errstr = "R1 type=inv expected=map_ptr",
},
{
"ARG_CONST_MAP_PTR: valid map pointer",
.insns = {
BPF_MOV64_IMM(BPF_REG_1, 0),
/* bpf_redirect_map arg1 (map) */
BPF_LD_MAP_FD(BPF_REG_1, 0),
/* bpf_redirect_map arg2 (ifindex) */
BPF_MOV64_IMM(BPF_REG_2, 0),
/* bpf_redirect_map arg3 (flags) */
BPF_MOV64_IMM(BPF_REG_3, 0),
BPF_EMIT_CALL(BPF_FUNC_redirect_map),
BPF_EXIT_INSN(),
},
.fixup_map_devmap = { 1 },
.result = ACCEPT,
.prog_type = BPF_PROG_TYPE_XDP,
},
{
"ARG_CONST_MAP_PTR_OR_NULL: null pointer for ex_map",
.insns = {
BPF_MOV64_IMM(BPF_REG_1, 0),
/* bpf_redirect_map_multi arg1 (in_map) */
BPF_LD_MAP_FD(BPF_REG_1, 0),
/* bpf_redirect_map_multi arg2 (ex_map) */
BPF_MOV64_IMM(BPF_REG_2, 0),
/* bpf_redirect_map_multi arg3 (flags) */
BPF_MOV64_IMM(BPF_REG_3, 0),
BPF_EMIT_CALL(BPF_FUNC_redirect_map_multi),
BPF_EXIT_INSN(),
},
.fixup_map_devmap = { 1 },
.result = ACCEPT,
.prog_type = BPF_PROG_TYPE_XDP,
.retval = 4,
},
{
"ARG_CONST_MAP_PTR_OR_NULL: valid map pointer for ex_map",
.insns = {
BPF_MOV64_IMM(BPF_REG_1, 0),
/* bpf_redirect_map_multi arg1 (in_map) */
BPF_LD_MAP_FD(BPF_REG_1, 0),
/* bpf_redirect_map_multi arg2 (ex_map) */
BPF_LD_MAP_FD(BPF_REG_2, 1),
/* bpf_redirect_map_multi arg3 (flags) */
BPF_MOV64_IMM(BPF_REG_3, 0),
BPF_EMIT_CALL(BPF_FUNC_redirect_map_multi),
BPF_EXIT_INSN(),
},
.fixup_map_devmap = { 1 },
.fixup_map_devmap_hash = { 3 },
.result = ACCEPT,
.prog_type = BPF_PROG_TYPE_XDP,
.retval = 4,
},

0 comments on commit 650db55

Please sign in to comment.