Make sure that wide stores are allowed at proper (aligned) addresses.
Note that user_ip6 is naturally aligned on 8-byte boundary, so
correct addresses are user_ip6[0] and user_ip6[2]. msg_src_ip6 is,
however, aligned on a 4-byte bondary, so only msg_src_ip6[1]
can be wide-stored.
Cc: Andrii Nakryiko <andriin@xxxxxx>
Cc: Yonghong Song <yhs@xxxxxx>
Acked-by: Andrii Nakryiko <andriin@xxxxxx>
Signed-off-by: Stanislav Fomichev <sdf@xxxxxxxxxx>
---
tools/testing/selftests/bpf/test_verifier.c | 17 +++++++--
.../selftests/bpf/verifier/wide_store.c | 36 +++++++++++++++++++
2 files changed, 50 insertions(+), 3 deletions(-)
create mode 100644 tools/testing/selftests/bpf/verifier/wide_store.c
diff --git a/tools/testing/selftests/bpf/test_verifier.c b/tools/testing/selftests/bpf/test_verifier.c
index c5514daf8865..b0773291012a 100644
--- a/tools/testing/selftests/bpf/test_verifier.c
+++ b/tools/testing/selftests/bpf/test_verifier.c
@@ -105,6 +105,7 @@ struct bpf_test {
__u64 data64[TEST_DATA_LEN / 8];
};
} retvals[MAX_TEST_RUNS];
+ enum bpf_attach_type expected_attach_type;
};
/* Note we want this to be 64 bit aligned so that the end of our array is
@@ -850,6 +851,7 @@ static void do_test_single(struct bpf_test *test, bool unpriv,
int fd_prog, expected_ret, alignment_prevented_execution;
int prog_len, prog_type = test->prog_type;
struct bpf_insn *prog = test->insns;
+ struct bpf_load_program_attr attr;
int run_errs, run_successes;
int map_fds[MAX_NR_MAPS];
const char *expected_err;
@@ -881,8 +883,17 @@ static void do_test_single(struct bpf_test *test, bool unpriv,
pflags |= BPF_F_STRICT_ALIGNMENT;
if (test->flags & F_NEEDS_EFFICIENT_UNALIGNED_ACCESS)
pflags |= BPF_F_ANY_ALIGNMENT;
- fd_prog = bpf_verify_program(prog_type, prog, prog_len, pflags,
- "GPL", 0, bpf_vlog, sizeof(bpf_vlog), 4);
+
+ memset(&attr, 0, sizeof(attr));
+ attr.prog_type = prog_type;
+ attr.expected_attach_type = test->expected_attach_type;
+ attr.insns = prog;
+ attr.insns_cnt = prog_len;
+ attr.license = "GPL";
+ attr.log_level = 4;
+ attr.prog_flags = pflags;
+
+ fd_prog = bpf_load_program_xattr(&attr, bpf_vlog, sizeof(bpf_vlog));
if (fd_prog < 0 && !bpf_probe_prog_type(prog_type, 0)) {
printf("SKIP (unsupported program type %d)\n", prog_type);
skips++;
@@ -912,7 +923,7 @@ static void do_test_single(struct bpf_test *test, bool unpriv,
printf("FAIL\nUnexpected success to load!\n");
goto fail_log;
}
- if (!strstr(bpf_vlog, expected_err)) {
+ if (!expected_err || !strstr(bpf_vlog, expected_err)) {
printf("FAIL\nUnexpected error message!\n\tEXP: %s\n\tRES: %s\n",
expected_err, bpf_vlog);
goto fail_log;
diff --git a/tools/testing/selftests/bpf/verifier/wide_store.c b/tools/testing/selftests/bpf/verifier/wide_store.c
new file mode 100644
index 000000000000..8fe99602ded4
--- /dev/null
+++ b/tools/testing/selftests/bpf/verifier/wide_store.c
@@ -0,0 +1,36 @@
+#define BPF_SOCK_ADDR(field, off, res, err) \
+{ \
+ "wide store to bpf_sock_addr." #field "[" #off "]", \
+ .insns = { \
+ BPF_MOV64_IMM(BPF_REG_0, 1), \
+ BPF_STX_MEM(BPF_DW, BPF_REG_1, BPF_REG_0, \
+ offsetof(struct bpf_sock_addr, field[off])), \
+ BPF_EXIT_INSN(), \
+ }, \
+ .result = res, \
+ .prog_type = BPF_PROG_TYPE_CGROUP_SOCK_ADDR, \
+ .expected_attach_type = BPF_CGROUP_UDP6_SENDMSG, \
+ .errstr = err, \
+}
+
+/* user_ip6[0] is u64 aligned */
+BPF_SOCK_ADDR(user_ip6, 0, ACCEPT,
+ NULL),
+BPF_SOCK_ADDR(user_ip6, 1, REJECT,
+ "invalid bpf_context access off=12 size=8"),
+BPF_SOCK_ADDR(user_ip6, 2, ACCEPT,
+ NULL),
+BPF_SOCK_ADDR(user_ip6, 3, REJECT,
+ "invalid bpf_context access off=20 size=8"),
+
+/* msg_src_ip6[0] is _not_ u64 aligned */
+BPF_SOCK_ADDR(msg_src_ip6, 0, REJECT,
+ "invalid bpf_context access off=44 size=8"),
+BPF_SOCK_ADDR(msg_src_ip6, 1, ACCEPT,
+ NULL),
+BPF_SOCK_ADDR(msg_src_ip6, 2, REJECT,
+ "invalid bpf_context access off=52 size=8"),
+BPF_SOCK_ADDR(msg_src_ip6, 3, REJECT,
+ "invalid bpf_context access off=56 size=8"),
+
+#undef BPF_SOCK_ADDR
--
2.22.0.410.gd8fdbe21b5-goog
