bpf: x86: add missing 'shift by register' instructions to x64 eBPF JIT

'shift by register' operations are supported by eBPF interpreter, but were
accidently left out of x64 JIT compiler. Fix it and add a testcase.

Reported-by: Brendan Gregg <brendan.d.gregg@gmail.com>
Signed-off-by: Alexei Starovoitov <ast@plumgrid.com>
Fixes: 622582786c ("net: filter: x86: internal BPF JIT")
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Alexei Starovoitov 2014-08-25 12:27:02 -07:00 committed by David S. Miller
parent 9785820e6d
commit 72b603ee8c
2 changed files with 80 additions and 0 deletions

View file

@ -1341,6 +1341,44 @@ static struct bpf_test tests[] = {
{ },
{ { 0, -1 } }
},
{
"INT: shifts by register",
.u.insns_int = {
BPF_MOV64_IMM(R0, -1234),
BPF_MOV64_IMM(R1, 1),
BPF_ALU32_REG(BPF_RSH, R0, R1),
BPF_JMP_IMM(BPF_JEQ, R0, 0x7ffffd97, 1),
BPF_EXIT_INSN(),
BPF_MOV64_IMM(R2, 1),
BPF_ALU64_REG(BPF_LSH, R0, R2),
BPF_MOV32_IMM(R4, -1234),
BPF_JMP_REG(BPF_JEQ, R0, R4, 1),
BPF_EXIT_INSN(),
BPF_ALU64_IMM(BPF_AND, R4, 63),
BPF_ALU64_REG(BPF_LSH, R0, R4), /* R0 <= 46 */
BPF_MOV64_IMM(R3, 47),
BPF_ALU64_REG(BPF_ARSH, R0, R3),
BPF_JMP_IMM(BPF_JEQ, R0, -617, 1),
BPF_EXIT_INSN(),
BPF_MOV64_IMM(R2, 1),
BPF_ALU64_REG(BPF_LSH, R4, R2), /* R4 = 46 << 1 */
BPF_JMP_IMM(BPF_JEQ, R4, 92, 1),
BPF_EXIT_INSN(),
BPF_MOV64_IMM(R4, 4),
BPF_ALU64_REG(BPF_LSH, R4, R4), /* R4 = 4 << 4 */
BPF_JMP_IMM(BPF_JEQ, R4, 64, 1),
BPF_EXIT_INSN(),
BPF_MOV64_IMM(R4, 5),
BPF_ALU32_REG(BPF_LSH, R4, R4), /* R4 = 5 << 5 */
BPF_JMP_IMM(BPF_JEQ, R4, 160, 1),
BPF_EXIT_INSN(),
BPF_MOV64_IMM(R0, -1),
BPF_EXIT_INSN(),
},
INTERNAL,
{ },
{ { 0, -1 } }
},
{
"INT: DIV + ABS",
.u.insns_int = {