linux/tools/testing/selftests/bpf/verifier/spill_fill.c

107 lines
3.0 KiB
C

{
"check valid spill/fill",
.insns = {
/* spill R1(ctx) into stack */
BPF_STX_MEM(BPF_DW, BPF_REG_10, BPF_REG_1, -8),
/* fill it back into R2 */
BPF_LDX_MEM(BPF_DW, BPF_REG_2, BPF_REG_10, -8),
/* should be able to access R0 = *(R2 + 8) */
/* BPF_LDX_MEM(BPF_DW, BPF_REG_0, BPF_REG_2, 8), */
BPF_MOV64_REG(BPF_REG_0, BPF_REG_2),
BPF_EXIT_INSN(),
},
.errstr_unpriv = "R0 leaks addr",
.result = ACCEPT,
.result_unpriv = REJECT,
.retval = POINTER_VALUE,
},
{
"check valid spill/fill, skb mark",
.insns = {
BPF_ALU64_REG(BPF_MOV, BPF_REG_6, BPF_REG_1),
BPF_STX_MEM(BPF_DW, BPF_REG_10, BPF_REG_6, -8),
BPF_LDX_MEM(BPF_DW, BPF_REG_0, BPF_REG_10, -8),
BPF_LDX_MEM(BPF_W, BPF_REG_0, BPF_REG_0,
offsetof(struct __sk_buff, mark)),
BPF_EXIT_INSN(),
},
.result = ACCEPT,
.result_unpriv = ACCEPT,
},
{
"check valid spill/fill, ptr to mem",
.insns = {
/* reserve 8 byte ringbuf memory */
BPF_ST_MEM(BPF_DW, BPF_REG_10, -8, 0),
BPF_LD_MAP_FD(BPF_REG_1, 0),
BPF_MOV64_IMM(BPF_REG_2, 8),
BPF_MOV64_IMM(BPF_REG_3, 0),
BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_ringbuf_reserve),
/* store a pointer to the reserved memory in R6 */
BPF_MOV64_REG(BPF_REG_6, BPF_REG_0),
/* check whether the reservation was successful */
BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 6),
/* spill R6(mem) into the stack */
BPF_STX_MEM(BPF_DW, BPF_REG_10, BPF_REG_6, -8),
/* fill it back in R7 */
BPF_LDX_MEM(BPF_DW, BPF_REG_7, BPF_REG_10, -8),
/* should be able to access *(R7) = 0 */
BPF_ST_MEM(BPF_DW, BPF_REG_7, 0, 0),
/* submit the reserved ringbuf memory */
BPF_MOV64_REG(BPF_REG_1, BPF_REG_7),
BPF_MOV64_IMM(BPF_REG_2, 0),
BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_ringbuf_submit),
BPF_MOV64_IMM(BPF_REG_0, 0),
BPF_EXIT_INSN(),
},
.fixup_map_ringbuf = { 1 },
.result = ACCEPT,
.result_unpriv = ACCEPT,
},
{
"check corrupted spill/fill",
.insns = {
/* spill R1(ctx) into stack */
BPF_STX_MEM(BPF_DW, BPF_REG_10, BPF_REG_1, -8),
/* mess up with R1 pointer on stack */
BPF_ST_MEM(BPF_B, BPF_REG_10, -7, 0x23),
/* fill back into R0 is fine for priv.
* R0 now becomes SCALAR_VALUE.
*/
BPF_LDX_MEM(BPF_DW, BPF_REG_0, BPF_REG_10, -8),
/* Load from R0 should fail. */
BPF_LDX_MEM(BPF_DW, BPF_REG_0, BPF_REG_0, 8),
BPF_EXIT_INSN(),
},
.errstr_unpriv = "attempt to corrupt spilled",
.errstr = "R0 invalid mem access 'inv",
.result = REJECT,
.flags = F_NEEDS_EFFICIENT_UNALIGNED_ACCESS,
},
{
"check corrupted spill/fill, LSB",
.insns = {
BPF_STX_MEM(BPF_DW, BPF_REG_10, BPF_REG_1, -8),
BPF_ST_MEM(BPF_H, BPF_REG_10, -8, 0xcafe),
BPF_LDX_MEM(BPF_DW, BPF_REG_0, BPF_REG_10, -8),
BPF_EXIT_INSN(),
},
.errstr_unpriv = "attempt to corrupt spilled",
.result_unpriv = REJECT,
.result = ACCEPT,
.retval = POINTER_VALUE,
},
{
"check corrupted spill/fill, MSB",
.insns = {
BPF_STX_MEM(BPF_DW, BPF_REG_10, BPF_REG_1, -8),
BPF_ST_MEM(BPF_W, BPF_REG_10, -4, 0x12345678),
BPF_LDX_MEM(BPF_DW, BPF_REG_0, BPF_REG_10, -8),
BPF_EXIT_INSN(),
},
.errstr_unpriv = "attempt to corrupt spilled",
.result_unpriv = REJECT,
.result = ACCEPT,
.retval = POINTER_VALUE,
},