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| author | Daniel Borkmann <daniel@iogearbox.net> | 2015-05-23 01:10:07 +0200 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2015-05-25 00:15:18 -0400 |
| commit | 3b52960266a36f7f2b577eb35cd97d2f64a5df26 (patch) | |
| tree | 3a53c1cd74f803649bc431f7f826b4ee993d17e5 /lib | |
| parent | cff497c8701ba5133e3407fd41430dc6159a3541 (diff) | |
| download | linux-3b52960266a36f7f2b577eb35cd97d2f64a5df26.tar.bz2 | |
test_bpf: add more eBPF jump torture cases
Add two more eBPF test cases for JITs, i.e. the second one revealed a
bug in the x86_64 JIT compiler, where only an int3 filled image from
the allocator was emitted and later wrongly set by the compiler as the
bpf_func program code since optimization pass boundary was surpassed
w/o actually emitting opcodes.
Interpreter:
[ 45.782892] test_bpf: #242 BPF_MAXINSNS: Very long jump backwards jited:0 11 PASS
[ 45.783062] test_bpf: #243 BPF_MAXINSNS: Edge hopping nuthouse jited:0 14705 PASS
After x86_64 JIT (fixed):
[ 80.495638] test_bpf: #242 BPF_MAXINSNS: Very long jump backwards jited:1 6 PASS
[ 80.495957] test_bpf: #243 BPF_MAXINSNS: Edge hopping nuthouse jited:1 17157 PASS
Reference: http://thread.gmane.org/gmane.linux.network/364729
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@plumgrid.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'lib')
| -rw-r--r-- | lib/test_bpf.c | 67 |
1 files changed, 67 insertions, 0 deletions
diff --git a/lib/test_bpf.c b/lib/test_bpf.c index 9b012a811ee1..c07b8e7db330 100644 --- a/lib/test_bpf.c +++ b/lib/test_bpf.c @@ -263,6 +263,57 @@ static int bpf_fill_maxinsns8(struct bpf_test *self) return 0; } +static int bpf_fill_maxinsns9(struct bpf_test *self) +{ + unsigned int len = BPF_MAXINSNS; + struct bpf_insn *insn; + int i; + + insn = kmalloc_array(len, sizeof(*insn), GFP_KERNEL); + if (!insn) + return -ENOMEM; + + insn[0] = BPF_JMP_IMM(BPF_JA, 0, 0, len - 2); + insn[1] = BPF_ALU32_IMM(BPF_MOV, R0, 0xcbababab); + insn[2] = BPF_EXIT_INSN(); + + for (i = 3; i < len - 2; i++) + insn[i] = BPF_ALU32_IMM(BPF_MOV, R0, 0xfefefefe); + + insn[len - 2] = BPF_EXIT_INSN(); + insn[len - 1] = BPF_JMP_IMM(BPF_JA, 0, 0, -(len - 1)); + + self->u.ptr.insns = insn; + self->u.ptr.len = len; + + return 0; +} + +static int bpf_fill_maxinsns10(struct bpf_test *self) +{ + unsigned int len = BPF_MAXINSNS, hlen = len - 2; + struct bpf_insn *insn; + int i; + + insn = kmalloc_array(len, sizeof(*insn), GFP_KERNEL); + if (!insn) + return -ENOMEM; + + for (i = 0; i < hlen / 2; i++) + insn[i] = BPF_JMP_IMM(BPF_JA, 0, 0, hlen - 2 - 2 * i); + for (i = hlen - 1; i > hlen / 2; i--) + insn[i] = BPF_JMP_IMM(BPF_JA, 0, 0, hlen - 1 - 2 * i); + + insn[hlen / 2] = BPF_JMP_IMM(BPF_JA, 0, 0, hlen / 2 - 1); + insn[hlen] = BPF_ALU32_IMM(BPF_MOV, R0, 0xabababac); + insn[hlen + 1] = BPF_EXIT_INSN(); + + self->u.ptr.insns = insn; + self->u.ptr.len = len; + + return 0; +} + static struct bpf_test tests[] = { { "TAX", @@ -4268,6 +4319,22 @@ static struct bpf_test tests[] = { { { 0, 0xffffffff } }, .fill_helper = bpf_fill_maxinsns8, }, + { /* Mainly checking JIT here. */ + "BPF_MAXINSNS: Very long jump backwards", + { }, + INTERNAL | FLAG_NO_DATA, + { }, + { { 0, 0xcbababab } }, + .fill_helper = bpf_fill_maxinsns9, + }, + { /* Mainly checking JIT here. */ + "BPF_MAXINSNS: Edge hopping nuthouse", + { }, + INTERNAL | FLAG_NO_DATA, + { }, + { { 0, 0xabababac } }, + .fill_helper = bpf_fill_maxinsns10, + }, }; static struct net_device dev; |