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authorDaniel Borkmann <daniel@iogearbox.net>2017-01-12 11:51:33 +0100
committerDavid S. Miller <davem@davemloft.net>2017-01-12 10:00:31 -0500
commit62c7989b24dbd348c2507ee6458ebf5637d6ddb5 (patch)
tree352050f1913fae4683e564607374618338c1c773 /tools/testing/selftests/bpf
parentbpf: pass original insn directly to convert_ctx_access (diff)
downloadlinux-dev-62c7989b24dbd348c2507ee6458ebf5637d6ddb5.tar.xz
linux-dev-62c7989b24dbd348c2507ee6458ebf5637d6ddb5.zip
bpf: allow b/h/w/dw access for bpf's cb in ctx
When structs are used to store temporary state in cb[] buffer that is used with programs and among tail calls, then the generated code will not always access the buffer in bpf_w chunks. We can ease programming of it and let this act more natural by allowing for aligned b/h/w/dw sized access for cb[] ctx member. Various test cases are attached as well for the selftest suite. Potentially, this can also be reused for other program types to pass data around. Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'tools/testing/selftests/bpf')
-rw-r--r--tools/testing/selftests/bpf/test_verifier.c442
1 files changed, 439 insertions, 3 deletions
diff --git a/tools/testing/selftests/bpf/test_verifier.c b/tools/testing/selftests/bpf/test_verifier.c
index 9bb45346dc72..1aa73241c999 100644
--- a/tools/testing/selftests/bpf/test_verifier.c
+++ b/tools/testing/selftests/bpf/test_verifier.c
@@ -859,15 +859,451 @@ static struct bpf_test tests[] = {
.result = REJECT,
},
{
- "check non-u32 access to cb",
+ "check cb access: byte",
.insns = {
- BPF_STX_MEM(BPF_H, BPF_REG_1, BPF_REG_1,
+ BPF_MOV64_IMM(BPF_REG_0, 0),
+ BPF_STX_MEM(BPF_B, BPF_REG_1, BPF_REG_0,
+ offsetof(struct __sk_buff, cb[0])),
+ BPF_STX_MEM(BPF_B, BPF_REG_1, BPF_REG_0,
+ offsetof(struct __sk_buff, cb[0]) + 1),
+ BPF_STX_MEM(BPF_B, BPF_REG_1, BPF_REG_0,
+ offsetof(struct __sk_buff, cb[0]) + 2),
+ BPF_STX_MEM(BPF_B, BPF_REG_1, BPF_REG_0,
+ offsetof(struct __sk_buff, cb[0]) + 3),
+ BPF_STX_MEM(BPF_B, BPF_REG_1, BPF_REG_0,
+ offsetof(struct __sk_buff, cb[1])),
+ BPF_STX_MEM(BPF_B, BPF_REG_1, BPF_REG_0,
+ offsetof(struct __sk_buff, cb[1]) + 1),
+ BPF_STX_MEM(BPF_B, BPF_REG_1, BPF_REG_0,
+ offsetof(struct __sk_buff, cb[1]) + 2),
+ BPF_STX_MEM(BPF_B, BPF_REG_1, BPF_REG_0,
+ offsetof(struct __sk_buff, cb[1]) + 3),
+ BPF_STX_MEM(BPF_B, BPF_REG_1, BPF_REG_0,
+ offsetof(struct __sk_buff, cb[2])),
+ BPF_STX_MEM(BPF_B, BPF_REG_1, BPF_REG_0,
+ offsetof(struct __sk_buff, cb[2]) + 1),
+ BPF_STX_MEM(BPF_B, BPF_REG_1, BPF_REG_0,
+ offsetof(struct __sk_buff, cb[2]) + 2),
+ BPF_STX_MEM(BPF_B, BPF_REG_1, BPF_REG_0,
+ offsetof(struct __sk_buff, cb[2]) + 3),
+ BPF_STX_MEM(BPF_B, BPF_REG_1, BPF_REG_0,
+ offsetof(struct __sk_buff, cb[3])),
+ BPF_STX_MEM(BPF_B, BPF_REG_1, BPF_REG_0,
+ offsetof(struct __sk_buff, cb[3]) + 1),
+ BPF_STX_MEM(BPF_B, BPF_REG_1, BPF_REG_0,
+ offsetof(struct __sk_buff, cb[3]) + 2),
+ BPF_STX_MEM(BPF_B, BPF_REG_1, BPF_REG_0,
+ offsetof(struct __sk_buff, cb[3]) + 3),
+ BPF_STX_MEM(BPF_B, BPF_REG_1, BPF_REG_0,
+ offsetof(struct __sk_buff, cb[4])),
+ BPF_STX_MEM(BPF_B, BPF_REG_1, BPF_REG_0,
+ offsetof(struct __sk_buff, cb[4]) + 1),
+ BPF_STX_MEM(BPF_B, BPF_REG_1, BPF_REG_0,
+ offsetof(struct __sk_buff, cb[4]) + 2),
+ BPF_STX_MEM(BPF_B, BPF_REG_1, BPF_REG_0,
+ offsetof(struct __sk_buff, cb[4]) + 3),
+ BPF_LDX_MEM(BPF_B, BPF_REG_0, BPF_REG_1,
+ offsetof(struct __sk_buff, cb[0])),
+ BPF_LDX_MEM(BPF_B, BPF_REG_0, BPF_REG_1,
+ offsetof(struct __sk_buff, cb[0]) + 1),
+ BPF_LDX_MEM(BPF_B, BPF_REG_0, BPF_REG_1,
+ offsetof(struct __sk_buff, cb[0]) + 2),
+ BPF_LDX_MEM(BPF_B, BPF_REG_0, BPF_REG_1,
+ offsetof(struct __sk_buff, cb[0]) + 3),
+ BPF_LDX_MEM(BPF_B, BPF_REG_0, BPF_REG_1,
+ offsetof(struct __sk_buff, cb[1])),
+ BPF_LDX_MEM(BPF_B, BPF_REG_0, BPF_REG_1,
+ offsetof(struct __sk_buff, cb[1]) + 1),
+ BPF_LDX_MEM(BPF_B, BPF_REG_0, BPF_REG_1,
+ offsetof(struct __sk_buff, cb[1]) + 2),
+ BPF_LDX_MEM(BPF_B, BPF_REG_0, BPF_REG_1,
+ offsetof(struct __sk_buff, cb[1]) + 3),
+ BPF_LDX_MEM(BPF_B, BPF_REG_0, BPF_REG_1,
+ offsetof(struct __sk_buff, cb[2])),
+ BPF_LDX_MEM(BPF_B, BPF_REG_0, BPF_REG_1,
+ offsetof(struct __sk_buff, cb[2]) + 1),
+ BPF_LDX_MEM(BPF_B, BPF_REG_0, BPF_REG_1,
+ offsetof(struct __sk_buff, cb[2]) + 2),
+ BPF_LDX_MEM(BPF_B, BPF_REG_0, BPF_REG_1,
+ offsetof(struct __sk_buff, cb[2]) + 3),
+ BPF_LDX_MEM(BPF_B, BPF_REG_0, BPF_REG_1,
+ offsetof(struct __sk_buff, cb[3])),
+ BPF_LDX_MEM(BPF_B, BPF_REG_0, BPF_REG_1,
+ offsetof(struct __sk_buff, cb[3]) + 1),
+ BPF_LDX_MEM(BPF_B, BPF_REG_0, BPF_REG_1,
+ offsetof(struct __sk_buff, cb[3]) + 2),
+ BPF_LDX_MEM(BPF_B, BPF_REG_0, BPF_REG_1,
+ offsetof(struct __sk_buff, cb[3]) + 3),
+ BPF_LDX_MEM(BPF_B, BPF_REG_0, BPF_REG_1,
+ offsetof(struct __sk_buff, cb[4])),
+ BPF_LDX_MEM(BPF_B, BPF_REG_0, BPF_REG_1,
+ offsetof(struct __sk_buff, cb[4]) + 1),
+ BPF_LDX_MEM(BPF_B, BPF_REG_0, BPF_REG_1,
+ offsetof(struct __sk_buff, cb[4]) + 2),
+ BPF_LDX_MEM(BPF_B, BPF_REG_0, BPF_REG_1,
+ offsetof(struct __sk_buff, cb[4]) + 3),
+ BPF_EXIT_INSN(),
+ },
+ .result = ACCEPT,
+ },
+ {
+ "check cb access: byte, oob 1",
+ .insns = {
+ BPF_MOV64_IMM(BPF_REG_0, 0),
+ BPF_STX_MEM(BPF_B, BPF_REG_1, BPF_REG_0,
+ offsetof(struct __sk_buff, cb[4]) + 4),
+ BPF_EXIT_INSN(),
+ },
+ .errstr = "invalid bpf_context access",
+ .result = REJECT,
+ },
+ {
+ "check cb access: byte, oob 2",
+ .insns = {
+ BPF_MOV64_IMM(BPF_REG_0, 0),
+ BPF_STX_MEM(BPF_B, BPF_REG_1, BPF_REG_0,
+ offsetof(struct __sk_buff, cb[0]) - 1),
+ BPF_EXIT_INSN(),
+ },
+ .errstr = "invalid bpf_context access",
+ .result = REJECT,
+ },
+ {
+ "check cb access: byte, oob 3",
+ .insns = {
+ BPF_MOV64_IMM(BPF_REG_0, 0),
+ BPF_LDX_MEM(BPF_B, BPF_REG_0, BPF_REG_1,
+ offsetof(struct __sk_buff, cb[4]) + 4),
+ BPF_EXIT_INSN(),
+ },
+ .errstr = "invalid bpf_context access",
+ .result = REJECT,
+ },
+ {
+ "check cb access: byte, oob 4",
+ .insns = {
+ BPF_MOV64_IMM(BPF_REG_0, 0),
+ BPF_LDX_MEM(BPF_B, BPF_REG_0, BPF_REG_1,
+ offsetof(struct __sk_buff, cb[0]) - 1),
+ BPF_EXIT_INSN(),
+ },
+ .errstr = "invalid bpf_context access",
+ .result = REJECT,
+ },
+ {
+ "check cb access: byte, wrong type",
+ .insns = {
+ BPF_MOV64_IMM(BPF_REG_0, 0),
+ BPF_STX_MEM(BPF_B, BPF_REG_1, BPF_REG_0,
+ offsetof(struct __sk_buff, cb[0])),
+ BPF_EXIT_INSN(),
+ },
+ .errstr = "invalid bpf_context access",
+ .result = REJECT,
+ .prog_type = BPF_PROG_TYPE_CGROUP_SOCK,
+ },
+ {
+ "check cb access: half",
+ .insns = {
+ BPF_MOV64_IMM(BPF_REG_0, 0),
+ BPF_STX_MEM(BPF_H, BPF_REG_1, BPF_REG_0,
+ offsetof(struct __sk_buff, cb[0])),
+ BPF_STX_MEM(BPF_H, BPF_REG_1, BPF_REG_0,
+ offsetof(struct __sk_buff, cb[0]) + 2),
+ BPF_STX_MEM(BPF_H, BPF_REG_1, BPF_REG_0,
+ offsetof(struct __sk_buff, cb[1])),
+ BPF_STX_MEM(BPF_H, BPF_REG_1, BPF_REG_0,
+ offsetof(struct __sk_buff, cb[1]) + 2),
+ BPF_STX_MEM(BPF_H, BPF_REG_1, BPF_REG_0,
+ offsetof(struct __sk_buff, cb[2])),
+ BPF_STX_MEM(BPF_H, BPF_REG_1, BPF_REG_0,
+ offsetof(struct __sk_buff, cb[2]) + 2),
+ BPF_STX_MEM(BPF_H, BPF_REG_1, BPF_REG_0,
+ offsetof(struct __sk_buff, cb[3])),
+ BPF_STX_MEM(BPF_H, BPF_REG_1, BPF_REG_0,
+ offsetof(struct __sk_buff, cb[3]) + 2),
+ BPF_STX_MEM(BPF_H, BPF_REG_1, BPF_REG_0,
+ offsetof(struct __sk_buff, cb[4])),
+ BPF_STX_MEM(BPF_H, BPF_REG_1, BPF_REG_0,
+ offsetof(struct __sk_buff, cb[4]) + 2),
+ BPF_LDX_MEM(BPF_H, BPF_REG_0, BPF_REG_1,
+ offsetof(struct __sk_buff, cb[0])),
+ BPF_LDX_MEM(BPF_H, BPF_REG_0, BPF_REG_1,
+ offsetof(struct __sk_buff, cb[0]) + 2),
+ BPF_LDX_MEM(BPF_H, BPF_REG_0, BPF_REG_1,
+ offsetof(struct __sk_buff, cb[1])),
+ BPF_LDX_MEM(BPF_H, BPF_REG_0, BPF_REG_1,
+ offsetof(struct __sk_buff, cb[1]) + 2),
+ BPF_LDX_MEM(BPF_H, BPF_REG_0, BPF_REG_1,
+ offsetof(struct __sk_buff, cb[2])),
+ BPF_LDX_MEM(BPF_H, BPF_REG_0, BPF_REG_1,
+ offsetof(struct __sk_buff, cb[2]) + 2),
+ BPF_LDX_MEM(BPF_H, BPF_REG_0, BPF_REG_1,
+ offsetof(struct __sk_buff, cb[3])),
+ BPF_LDX_MEM(BPF_H, BPF_REG_0, BPF_REG_1,
+ offsetof(struct __sk_buff, cb[3]) + 2),
+ BPF_LDX_MEM(BPF_H, BPF_REG_0, BPF_REG_1,
+ offsetof(struct __sk_buff, cb[4])),
+ BPF_LDX_MEM(BPF_H, BPF_REG_0, BPF_REG_1,
+ offsetof(struct __sk_buff, cb[4]) + 2),
+ BPF_EXIT_INSN(),
+ },
+ .result = ACCEPT,
+ },
+ {
+ "check cb access: half, unaligned",
+ .insns = {
+ BPF_MOV64_IMM(BPF_REG_0, 0),
+ BPF_STX_MEM(BPF_H, BPF_REG_1, BPF_REG_0,
+ offsetof(struct __sk_buff, cb[0]) + 1),
+ BPF_EXIT_INSN(),
+ },
+ .errstr = "misaligned access",
+ .result = REJECT,
+ },
+ {
+ "check cb access: half, oob 1",
+ .insns = {
+ BPF_MOV64_IMM(BPF_REG_0, 0),
+ BPF_STX_MEM(BPF_H, BPF_REG_1, BPF_REG_0,
+ offsetof(struct __sk_buff, cb[4]) + 4),
+ BPF_EXIT_INSN(),
+ },
+ .errstr = "invalid bpf_context access",
+ .result = REJECT,
+ },
+ {
+ "check cb access: half, oob 2",
+ .insns = {
+ BPF_MOV64_IMM(BPF_REG_0, 0),
+ BPF_STX_MEM(BPF_H, BPF_REG_1, BPF_REG_0,
+ offsetof(struct __sk_buff, cb[0]) - 2),
+ BPF_EXIT_INSN(),
+ },
+ .errstr = "invalid bpf_context access",
+ .result = REJECT,
+ },
+ {
+ "check cb access: half, oob 3",
+ .insns = {
+ BPF_MOV64_IMM(BPF_REG_0, 0),
+ BPF_LDX_MEM(BPF_H, BPF_REG_0, BPF_REG_1,
+ offsetof(struct __sk_buff, cb[4]) + 4),
+ BPF_EXIT_INSN(),
+ },
+ .errstr = "invalid bpf_context access",
+ .result = REJECT,
+ },
+ {
+ "check cb access: half, oob 4",
+ .insns = {
+ BPF_MOV64_IMM(BPF_REG_0, 0),
+ BPF_LDX_MEM(BPF_H, BPF_REG_0, BPF_REG_1,
+ offsetof(struct __sk_buff, cb[0]) - 2),
+ BPF_EXIT_INSN(),
+ },
+ .errstr = "invalid bpf_context access",
+ .result = REJECT,
+ },
+ {
+ "check cb access: half, wrong type",
+ .insns = {
+ BPF_MOV64_IMM(BPF_REG_0, 0),
+ BPF_STX_MEM(BPF_H, BPF_REG_1, BPF_REG_0,
+ offsetof(struct __sk_buff, cb[0])),
+ BPF_EXIT_INSN(),
+ },
+ .errstr = "invalid bpf_context access",
+ .result = REJECT,
+ .prog_type = BPF_PROG_TYPE_CGROUP_SOCK,
+ },
+ {
+ "check cb access: word",
+ .insns = {
+ BPF_MOV64_IMM(BPF_REG_0, 0),
+ BPF_STX_MEM(BPF_W, BPF_REG_1, BPF_REG_0,
+ offsetof(struct __sk_buff, cb[0])),
+ BPF_STX_MEM(BPF_W, BPF_REG_1, BPF_REG_0,
+ offsetof(struct __sk_buff, cb[1])),
+ BPF_STX_MEM(BPF_W, BPF_REG_1, BPF_REG_0,
+ offsetof(struct __sk_buff, cb[2])),
+ BPF_STX_MEM(BPF_W, BPF_REG_1, BPF_REG_0,
+ offsetof(struct __sk_buff, cb[3])),
+ BPF_STX_MEM(BPF_W, BPF_REG_1, BPF_REG_0,
+ offsetof(struct __sk_buff, cb[4])),
+ BPF_LDX_MEM(BPF_W, BPF_REG_0, BPF_REG_1,
+ offsetof(struct __sk_buff, cb[0])),
+ BPF_LDX_MEM(BPF_W, BPF_REG_0, BPF_REG_1,
+ offsetof(struct __sk_buff, cb[1])),
+ BPF_LDX_MEM(BPF_W, BPF_REG_0, BPF_REG_1,
+ offsetof(struct __sk_buff, cb[2])),
+ BPF_LDX_MEM(BPF_W, BPF_REG_0, BPF_REG_1,
+ offsetof(struct __sk_buff, cb[3])),
+ BPF_LDX_MEM(BPF_W, BPF_REG_0, BPF_REG_1,
+ offsetof(struct __sk_buff, cb[4])),
+ BPF_EXIT_INSN(),
+ },
+ .result = ACCEPT,
+ },
+ {
+ "check cb access: word, unaligned 1",
+ .insns = {
+ BPF_MOV64_IMM(BPF_REG_0, 0),
+ BPF_STX_MEM(BPF_W, BPF_REG_1, BPF_REG_0,
+ offsetof(struct __sk_buff, cb[0]) + 2),
+ BPF_EXIT_INSN(),
+ },
+ .errstr = "misaligned access",
+ .result = REJECT,
+ },
+ {
+ "check cb access: word, unaligned 2",
+ .insns = {
+ BPF_MOV64_IMM(BPF_REG_0, 0),
+ BPF_STX_MEM(BPF_W, BPF_REG_1, BPF_REG_0,
+ offsetof(struct __sk_buff, cb[4]) + 1),
+ BPF_EXIT_INSN(),
+ },
+ .errstr = "misaligned access",
+ .result = REJECT,
+ },
+ {
+ "check cb access: word, unaligned 3",
+ .insns = {
+ BPF_MOV64_IMM(BPF_REG_0, 0),
+ BPF_STX_MEM(BPF_W, BPF_REG_1, BPF_REG_0,
+ offsetof(struct __sk_buff, cb[4]) + 2),
+ BPF_EXIT_INSN(),
+ },
+ .errstr = "misaligned access",
+ .result = REJECT,
+ },
+ {
+ "check cb access: word, unaligned 4",
+ .insns = {
+ BPF_MOV64_IMM(BPF_REG_0, 0),
+ BPF_STX_MEM(BPF_W, BPF_REG_1, BPF_REG_0,
+ offsetof(struct __sk_buff, cb[4]) + 3),
+ BPF_EXIT_INSN(),
+ },
+ .errstr = "misaligned access",
+ .result = REJECT,
+ },
+ {
+ "check cb access: double",
+ .insns = {
+ BPF_MOV64_IMM(BPF_REG_0, 0),
+ BPF_STX_MEM(BPF_DW, BPF_REG_1, BPF_REG_0,
+ offsetof(struct __sk_buff, cb[0])),
+ BPF_STX_MEM(BPF_DW, BPF_REG_1, BPF_REG_0,
+ offsetof(struct __sk_buff, cb[2])),
+ BPF_LDX_MEM(BPF_DW, BPF_REG_0, BPF_REG_1,
+ offsetof(struct __sk_buff, cb[0])),
+ BPF_LDX_MEM(BPF_DW, BPF_REG_0, BPF_REG_1,
+ offsetof(struct __sk_buff, cb[2])),
+ BPF_EXIT_INSN(),
+ },
+ .result = ACCEPT,
+ },
+ {
+ "check cb access: double, unaligned 1",
+ .insns = {
+ BPF_MOV64_IMM(BPF_REG_0, 0),
+ BPF_STX_MEM(BPF_DW, BPF_REG_1, BPF_REG_0,
+ offsetof(struct __sk_buff, cb[1])),
+ BPF_EXIT_INSN(),
+ },
+ .errstr = "misaligned access",
+ .result = REJECT,
+ },
+ {
+ "check cb access: double, unaligned 2",
+ .insns = {
+ BPF_MOV64_IMM(BPF_REG_0, 0),
+ BPF_STX_MEM(BPF_DW, BPF_REG_1, BPF_REG_0,
+ offsetof(struct __sk_buff, cb[3])),
+ BPF_EXIT_INSN(),
+ },
+ .errstr = "misaligned access",
+ .result = REJECT,
+ },
+ {
+ "check cb access: double, oob 1",
+ .insns = {
+ BPF_MOV64_IMM(BPF_REG_0, 0),
+ BPF_STX_MEM(BPF_DW, BPF_REG_1, BPF_REG_0,
+ offsetof(struct __sk_buff, cb[4])),
+ BPF_EXIT_INSN(),
+ },
+ .errstr = "invalid bpf_context access",
+ .result = REJECT,
+ },
+ {
+ "check cb access: double, oob 2",
+ .insns = {
+ BPF_MOV64_IMM(BPF_REG_0, 0),
+ BPF_STX_MEM(BPF_DW, BPF_REG_1, BPF_REG_0,
+ offsetof(struct __sk_buff, cb[4]) + 8),
+ BPF_EXIT_INSN(),
+ },
+ .errstr = "invalid bpf_context access",
+ .result = REJECT,
+ },
+ {
+ "check cb access: double, oob 3",
+ .insns = {
+ BPF_MOV64_IMM(BPF_REG_0, 0),
+ BPF_STX_MEM(BPF_DW, BPF_REG_1, BPF_REG_0,
+ offsetof(struct __sk_buff, cb[0]) - 8),
+ BPF_EXIT_INSN(),
+ },
+ .errstr = "invalid bpf_context access",
+ .result = REJECT,
+ },
+ {
+ "check cb access: double, oob 4",
+ .insns = {
+ BPF_MOV64_IMM(BPF_REG_0, 0),
+ BPF_LDX_MEM(BPF_DW, BPF_REG_0, BPF_REG_1,
+ offsetof(struct __sk_buff, cb[4])),
+ BPF_EXIT_INSN(),
+ },
+ .errstr = "invalid bpf_context access",
+ .result = REJECT,
+ },
+ {
+ "check cb access: double, oob 5",
+ .insns = {
+ BPF_MOV64_IMM(BPF_REG_0, 0),
+ BPF_LDX_MEM(BPF_DW, BPF_REG_0, BPF_REG_1,
+ offsetof(struct __sk_buff, cb[4]) + 8),
+ BPF_EXIT_INSN(),
+ },
+ .errstr = "invalid bpf_context access",
+ .result = REJECT,
+ },
+ {
+ "check cb access: double, oob 6",
+ .insns = {
+ BPF_MOV64_IMM(BPF_REG_0, 0),
+ BPF_LDX_MEM(BPF_DW, BPF_REG_0, BPF_REG_1,
+ offsetof(struct __sk_buff, cb[0]) - 8),
+ BPF_EXIT_INSN(),
+ },
+ .errstr = "invalid bpf_context access",
+ .result = REJECT,
+ },
+ {
+ "check cb access: double, wrong type",
+ .insns = {
+ BPF_MOV64_IMM(BPF_REG_0, 0),
+ BPF_STX_MEM(BPF_DW, BPF_REG_1, BPF_REG_0,
offsetof(struct __sk_buff, cb[0])),
BPF_EXIT_INSN(),
},
.errstr = "invalid bpf_context access",
- .errstr_unpriv = "R1 leaks addr",
.result = REJECT,
+ .prog_type = BPF_PROG_TYPE_CGROUP_SOCK,
},
{
"check out of range skb->cb access",