{
"atomic compare-and-exchange smoketest - 64bit",
.insns = {
/* val = 3; */
BPF_ST_MEM(BPF_DW, BPF_REG_10, -8, 3),
/* old = atomic_cmpxchg(&val, 2, 4); */
BPF_MOV64_IMM(BPF_REG_1, 4),
BPF_MOV64_IMM(BPF_REG_0, 2),
BPF_ATOMIC_OP(BPF_DW, BPF_CMPXCHG, BPF_REG_10, BPF_REG_1, -8),
/* if (old != 3) exit(2); */
BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 3, 2),
BPF_MOV64_IMM(BPF_REG_0, 2),
BPF_EXIT_INSN(),
/* if (val != 3) exit(3); */
BPF_LDX_MEM(BPF_DW, BPF_REG_0, BPF_REG_10, -8),
BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 3, 2),
BPF_MOV64_IMM(BPF_REG_0, 3),
BPF_EXIT_INSN(),
/* old = atomic_cmpxchg(&val, 3, 4); */
BPF_MOV64_IMM(BPF_REG_1, 4),
BPF_MOV64_IMM(BPF_REG_0, 3),
BPF_ATOMIC_OP(BPF_DW, BPF_CMPXCHG, BPF_REG_10, BPF_REG_1, -8),
/* if (old != 3) exit(4); */
BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 3, 2),
BPF_MOV64_IMM(BPF_REG_0, 4),
BPF_EXIT_INSN(),
/* if (val != 4) exit(5); */
BPF_LDX_MEM(BPF_DW, BPF_REG_0, BPF_REG_10, -8),
BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 4, 2),
BPF_MOV64_IMM(BPF_REG_0, 5),
BPF_EXIT_INSN(),
/* exit(0); */
BPF_MOV64_IMM(BPF_REG_0, 0),
BPF_EXIT_INSN(),
},
.result = ACCEPT,
},
{
"atomic compare-and-exchange smoketest - 32bit",
.insns = {
/* val = 3; */
BPF_ST_MEM(BPF_W, BPF_REG_10, -4, 3),
/* old = atomic_cmpxchg(&val, 2, 4); */
BPF_MOV32_IMM(BPF_REG_1, 4),
BPF_MOV32_IMM(BPF_REG_0, 2),
BPF_ATOMIC_OP(BPF_W, BPF_CMPXCHG, BPF_REG_10, BPF_REG_1, -4),
/* if (old != 3) exit(2); */
BPF_JMP32_IMM(BPF_JEQ, BPF_REG_0, 3, 2),
BPF_MOV32_IMM(BPF_REG_0, 2),
BPF_EXIT_INSN(),
/* if (val != 3) exit(3); */
BPF_LDX_MEM(BPF_W, BPF_REG_0, BPF_REG_10, -4),
BPF_JMP32_IMM(BPF_JEQ, BPF_REG_0, 3, 2),
BPF_MOV32_IMM(BPF_REG_0, 3),
BPF_EXIT_INSN(),
/* old = atomic_cmpxchg(&val, 3, 4); */
BPF_MOV32_IMM(BPF_REG_1, 4),
BPF_MOV32_IMM(BPF_REG_0, 3),
BPF_ATOMIC_OP(BPF_W, BPF_CMPXCHG, BPF_REG_10, BPF_REG_1, -4),
/* if (old != 3) exit(4); */
BPF_JMP32_IMM(BPF_JEQ, BPF_REG_0, 3, 2),
BPF_MOV32_IMM(BPF_REG_0, 4),
BPF_EXIT_INSN(),
/* if (val != 4) exit(5); */
BPF_LDX_MEM(BPF_W, BPF_REG_0, BPF_REG_10, -4),
BPF_JMP32_IMM(BPF_JEQ, BPF_REG_0, 4, 2),
BPF_MOV32_IMM(BPF_REG_0, 5),
BPF_EXIT_INSN(),
/* exit(0); */
BPF_MOV32_IMM(BPF_REG_0, 0),
BPF_EXIT_INSN(),
},
.result = ACCEPT,
},
{
"Can't use cmpxchg on uninit src reg",
.insns = {
BPF_ST_MEM(BPF_DW, BPF_REG_10, -8, 3),
BPF_MOV64_IMM(BPF_REG_0, 3),
BPF_ATOMIC_OP(BPF_DW, BPF_CMPXCHG, BPF_REG_10, BPF_REG_2, -8),
BPF_EXIT_INSN(),
},
.result = REJECT,
.errstr = "!read_ok",
},
{
"BPF_W cmpxchg should zero top 32 bits",
.insns = {
/* r0 = U64_MAX; */
BPF_MOV64_IMM(BPF_REG_0, 0),
BPF_ALU64_IMM(BPF_SUB, BPF_REG_0, 1),
/* u64 val = r0; */
BPF_STX_MEM(BPF_DW, BPF_REG_10, BPF_REG_0, -8),
/* r0 = (u32)atomic_cmpxchg((u32 *)&val, r0, 1); */
BPF_MOV32_IMM(BPF_REG_1, 1),
BPF_ATOMIC_OP(BPF_W, BPF_CMPXCHG, BPF_REG_10, BPF_REG_1, -8),
/* r1 = 0x00000000FFFFFFFFull; */
BPF_MOV64_IMM(BPF_REG_1, 1),
BPF_ALU64_IMM(BPF_LSH, BPF_REG_1, 32),
BPF_ALU64_IMM(BPF_SUB, BPF_REG_1, 1),
/* if (r0 != r1) exit(1); */
BPF_JMP_REG(BPF_JEQ, BPF_REG_0, BPF_REG_1, 2),
BPF_MOV32_IMM(BPF_REG_0, 1),
BPF_EXIT_INSN(),
/* exit(0); */
BPF_MOV32_IMM(BPF_REG_0, 0),
BPF_EXIT_INSN(),
},
.result = ACCEPT,
},
{
"Dest pointer in r0 - fail",
.insns = {
/* val = 0; */
BPF_ST_MEM(BPF_DW, BPF_REG_10, -8, 0),
/* r0 = &val */
BPF_MOV64_REG(BPF_REG_0, BPF_REG_10),
/* r0 = atomic_cmpxchg(&val, r0, 1); */
BPF_MOV64_IMM(BPF_REG_1, 1),
BPF_ATOMIC_OP(BPF_DW, BPF_CMPXCHG, BPF_REG_10, BPF_REG_1, -8),
/* if (r0 != 0) exit(1); */
BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 2),
BPF_MOV64_IMM(BPF_REG_0, 1),
BPF_EXIT_INSN(),
/* exit(0); */
BPF_MOV64_IMM(BPF_REG_0, 0),
BPF_EXIT_INSN(),
},
.result = ACCEPT,
.result_unpriv = REJECT,
.errstr_unpriv = "R0 leaks addr into mem",
},
{
"Dest pointer in r0 - succeed",
.insns = {
/* r0 = &val */
BPF_MOV64_REG(BPF_REG_0, BPF_REG_10),
/* val = r0; */
BPF_STX_MEM(BPF_DW, BPF_REG_10, BPF_REG_0, -8),
/* r0 = atomic_cmpxchg(&val, r0, 0); */
BPF_MOV64_IMM(BPF_REG_1, 0),
BPF_ATOMIC_OP(BPF_DW, BPF_CMPXCHG, BPF_REG_10, BPF_REG_1, -8),
/* r1 = *r0 */
BPF_LDX_MEM(BPF_DW, BPF_REG_1, BPF_REG_0, -8),
/* exit(0); */
BPF_MOV64_IMM(BPF_REG_0, 0),
BPF_EXIT_INSN(),
},
.result = ACCEPT,
.result_unpriv = REJECT,
.errstr_unpriv = "R0 leaks addr into mem",
},
{
"Dest pointer in r0 - succeed, check 2",
.insns = {
/* r0 = &val */
BPF_MOV64_REG(BPF_REG_0, BPF_REG_10),
/* val = r0; */
BPF_STX_MEM(BPF_DW, BPF_REG_10, BPF_REG_0, -8),
/* r5 = &val */
BPF_MOV64_REG(BPF_REG_5, BPF_REG_10),
/* r0 = atomic_cmpxchg(&val, r0, r5); */
BPF_ATOMIC_OP(BPF_DW, BPF_CMPXCHG, BPF_REG_10, BPF_REG_5, -8),
/* r1 = *r0 */
BPF_LDX_MEM(BPF_DW, BPF_REG_1, BPF_REG_0, -8),
/* exit(0); */
BPF_MOV64_IMM(BPF_REG_0, 0),
BPF_EXIT_INSN(),
},
.result = ACCEPT,
.result_unpriv = REJECT,
.errstr_unpriv = "R0 leaks addr into mem",
},
{
"Dest pointer in r0 - succeed, check 3",
.insns = {
/* r0 = &val */
BPF_MOV64_REG(BPF_REG_0, BPF_REG_10),
/* val = r0; */
BPF_STX_MEM(BPF_DW, BPF_REG_10, BPF_REG_0, -8),
/* r5 = &val */
BPF_MOV64_REG(BPF_REG_5, BPF_REG_10),
/* r0 = atomic_cmpxchg(&val, r0, r5); */
BPF_ATOMIC_OP(BPF_W, BPF_CMPXCHG, BPF_REG_10, BPF_REG_5, -8),
/* exit(0); */
BPF_MOV64_IMM(BPF_REG_0, 0),
BPF_EXIT_INSN(),
},
.result = REJECT,
.errstr = "invalid size of register fill",
.errstr_unpriv = "R0 leaks addr into mem",
},
{
"Dest pointer in r0 - succeed, check 4",
.insns = {
/* r0 = &val */
BPF_MOV32_REG(BPF_REG_0, BPF_REG_10),
/* val = r0; */
BPF_STX_MEM(BPF_W, BPF_REG_10, BPF_REG_0, -8),
/* r5 = &val */
BPF_MOV32_REG(BPF_REG_5, BPF_REG_10),
/* r0 = atomic_cmpxchg(&val, r0, r5); */
BPF_ATOMIC_OP(BPF_W, BPF_CMPXCHG, BPF_REG_10, BPF_REG_5, -8),
/* r1 = *r10 */
BPF_LDX_MEM(BPF_W, BPF_REG_1, BPF_REG_10, -8),
/* exit(0); */
BPF_MOV64_IMM(BPF_REG_0, 0),
BPF_EXIT_INSN(),
},
.result = ACCEPT,
.result_unpriv = REJECT,
.errstr_unpriv = "R10 partial copy of pointer",
},
{
"Dest pointer in r0 - succeed, check 5",
.insns = {
/* r0 = &val */
BPF_MOV32_REG(BPF_REG_0, BPF_REG_10),
/* val = r0; */
BPF_STX_MEM(BPF_W, BPF_REG_10, BPF_REG_0, -8),
/* r5 = &val */
BPF_MOV32_REG(BPF_REG_5, BPF_REG_10),
/* r0 = atomic_cmpxchg(&val, r0, r5); */
BPF_ATOMIC_OP(BPF_W, BPF_CMPXCHG, BPF_REG_10, BPF_REG_5, -8),
/* r1 = *r0 */
BPF_LDX_MEM(BPF_W, BPF_REG_1, BPF_REG_0, -8),
/* exit(0); */
BPF_MOV64_IMM(BPF_REG_0, 0),
BPF_EXIT_INSN(),
},
.result = REJECT,
.errstr = "R0 invalid mem access",
.errstr_unpriv = "R10 partial copy of pointer",
.flags = F_NEEDS_EFFICIENT_UNALIGNED_ACCESS,
},
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