lkml.org 
[lkml]   [2022]   [Nov]   [25]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    Patch in this message
    /
    From
    Subject[PATCH bpf-next v3 3/3] selftests/bpf: Add tests for LDX/STX/ST sanitize
    Date
    Add tests for LDX/STX/ST instrumentation in each possible case.
    Five cases for STX/ST, nice cases for LDX. All new/existing
    selftests can pass.

    A slab-out-of-bounds read report is also availble, which is
    achieved by exploiting CVE-2022-23222 and can be reproduced
    in Linux v5.10: https://pastebin.com/raw/Ee1Cw492

    Signed-off-by: Hao Sun <sunhao.th@gmail.com>
    ---
    .../selftests/bpf/verifier/sanitize_st_ldx.c | 317 ++++++++++++++++++
    1 file changed, 317 insertions(+)
    create mode 100644 tools/testing/selftests/bpf/verifier/sanitize_st_ldx.c

    diff --git a/tools/testing/selftests/bpf/verifier/sanitize_st_ldx.c b/tools/testing/selftests/bpf/verifier/sanitize_st_ldx.c
    new file mode 100644
    index 000000000000..dfd53f97eb95
    --- /dev/null
    +++ b/tools/testing/selftests/bpf/verifier/sanitize_st_ldx.c
    @@ -0,0 +1,317 @@
    +#ifdef CONFIG_BPF_PROG_KASAN
    +
    +#define __BACKUP_REG(n) \
    + BPF_STX_MEM(BPF_DW, BPF_REG_10, BPF_REG_##n, INSN_OFF_MASK)
    +#define BACKUP_SCRATCH_REGS \
    + __BACKUP_REG(1), __BACKUP_REG(2), __BACKUP_REG(3), __BACKUP_REG(4), \
    + __BACKUP_REG(5)
    +
    +#define __RESTORE_REG(n) \
    + BPF_LDX_MEM(BPF_DW, BPF_REG_##n, BPF_REG_10, INSN_OFF_MASK)
    +#define RESTORE_SCRATCH_REGS \
    + __RESTORE_REG(1), __RESTORE_REG(2), __RESTORE_REG(3), \
    + __RESTORE_REG(4), __RESTORE_REG(5)
    +
    +{
    + "sanitize stx: dst is R1, off is zero",
    + .insns = {
    + BPF_MOV64_REG(BPF_REG_1, BPF_REG_10),
    + BPF_ALU64_IMM(BPF_ADD, BPF_REG_1, -8),
    + BPF_ST_MEM(BPF_DW, BPF_REG_1, 0, 1),
    + BPF_LDX_MEM(BPF_DW, BPF_REG_0, BPF_REG_1, 0),
    + BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 1, 1),
    + BPF_MOV64_IMM(BPF_REG_0, 2),
    + BPF_EXIT_INSN(),
    + },
    + .result = ACCEPT,
    + .retval = 1,
    + .expected_insns = {
    + BACKUP_SCRATCH_REGS,
    + BPF_MOV64_REG(MAX_BPF_REG, BPF_REG_0),
    + BPF_EMIT_CALL(INSN_IMM_MASK),
    + RESTORE_SCRATCH_REGS,
    + BPF_MOV64_REG(BPF_REG_0, MAX_BPF_REG),
    + BPF_ST_MEM(BPF_DW, BPF_REG_1, 0, 1),
    + },
    +},
    +{
    + "sanitize stx: dst is R1",
    + .insns = {
    + BPF_MOV64_REG(BPF_REG_1, BPF_REG_10),
    + BPF_ST_MEM(BPF_DW, BPF_REG_1, -8, 1),
    + BPF_LDX_MEM(BPF_DW, BPF_REG_1, BPF_REG_1, -8),
    + BPF_JMP_IMM(BPF_JEQ, BPF_REG_1, 1, 2),
    + BPF_MOV64_IMM(BPF_REG_0, 2),
    + BPF_EXIT_INSN(),
    + BPF_MOV64_REG(BPF_REG_0, BPF_REG_1),
    + BPF_EXIT_INSN(),
    + },
    + .result = ACCEPT,
    + .retval = 1,
    + .expected_insns = {
    + BACKUP_SCRATCH_REGS,
    + BPF_MOV64_REG(MAX_BPF_REG, BPF_REG_0),
    + BPF_ALU64_IMM(BPF_ADD, BPF_REG_1, -8),
    + BPF_EMIT_CALL(INSN_IMM_MASK),
    + RESTORE_SCRATCH_REGS,
    + BPF_MOV64_REG(BPF_REG_0, MAX_BPF_REG),
    + BPF_ST_MEM(BPF_DW, BPF_REG_1, -8, 1),
    + },
    +},
    +{
    + "sanitize stx: dst is other regs, off is zero",
    + .insns = {
    + BPF_MOV64_REG(BPF_REG_2, BPF_REG_10),
    + BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -8),
    + BPF_ST_MEM(BPF_DW, BPF_REG_2, 0, 1),
    + BPF_LDX_MEM(BPF_DW, BPF_REG_0, BPF_REG_2, 0),
    + BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 1, 1),
    + BPF_MOV64_IMM(BPF_REG_0, 2),
    + BPF_EXIT_INSN(),
    + },
    + .result = ACCEPT,
    + .retval = 1,
    + .expected_insns = {
    + BACKUP_SCRATCH_REGS,
    + BPF_MOV64_REG(MAX_BPF_REG, BPF_REG_0),
    + BPF_MOV64_REG(BPF_REG_1, BPF_REG_2),
    + BPF_EMIT_CALL(INSN_IMM_MASK),
    + RESTORE_SCRATCH_REGS,
    + BPF_MOV64_REG(BPF_REG_0, MAX_BPF_REG),
    + BPF_ST_MEM(BPF_DW, BPF_REG_2, 0, 1),
    + },
    +},
    +{
    + "sanitize stx: dst is other regs",
    + .insns = {
    + BPF_MOV64_REG(BPF_REG_2, BPF_REG_10),
    + BPF_ST_MEM(BPF_DW, BPF_REG_2, -8, 1),
    + BPF_LDX_MEM(BPF_DW, BPF_REG_0, BPF_REG_2, -8),
    + BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 1, 1),
    + BPF_MOV64_IMM(BPF_REG_0, 2),
    + BPF_EXIT_INSN(),
    + },
    + .result = ACCEPT,
    + .retval = 1,
    + .expected_insns = {
    + BACKUP_SCRATCH_REGS,
    + BPF_MOV64_REG(MAX_BPF_REG, BPF_REG_0),
    + BPF_MOV64_REG(BPF_REG_1, BPF_REG_2),
    + BPF_ALU64_IMM(BPF_ADD, BPF_REG_1, -8),
    + BPF_EMIT_CALL(INSN_IMM_MASK),
    + RESTORE_SCRATCH_REGS,
    + BPF_MOV64_REG(BPF_REG_0, MAX_BPF_REG),
    + BPF_ST_MEM(BPF_DW, BPF_REG_2, -8, 1),
    + },
    +},
    +{
    + "sanitize stx: dst is R10",
    + .insns = {
    + BPF_ST_MEM(BPF_DW, BPF_REG_10, -8, 1),
    + BPF_LDX_MEM(BPF_DW, BPF_REG_0, BPF_REG_10, -8),
    + BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 1, 1),
    + BPF_MOV64_IMM(BPF_REG_0, 2),
    + BPF_EXIT_INSN(),
    + },
    + .result = ACCEPT,
    + .retval = 1,
    + .unexpected_insns = {
    + BPF_EMIT_CALL(INSN_IMM_MASK),
    + },
    +},
    +{
    + "sanitize ldx: src is R1, dst is R0, off is zero",
    + .insns = {
    + BPF_MOV64_REG(BPF_REG_1, BPF_REG_10),
    + BPF_ALU64_IMM(BPF_ADD, BPF_REG_1, -8),
    + BPF_ST_MEM(BPF_DW, BPF_REG_1, 0, 1),
    + BPF_LDX_MEM(BPF_DW, BPF_REG_0, BPF_REG_1, 0),
    + BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 1, 1),
    + BPF_MOV64_IMM(BPF_REG_0, 2),
    + BPF_EXIT_INSN(),
    + },
    + .result = ACCEPT,
    + .retval = 1,
    + .expected_insns = {
    + BACKUP_SCRATCH_REGS,
    + BPF_EMIT_CALL(INSN_IMM_MASK),
    + RESTORE_SCRATCH_REGS,
    + BPF_LDX_MEM(BPF_DW, BPF_REG_0, BPF_REG_1, 0),
    + },
    +},
    +{
    + "sanitize ldx: src is R1, dst is R0",
    + .insns = {
    + BPF_MOV64_REG(BPF_REG_1, BPF_REG_10),
    + BPF_ST_MEM(BPF_DW, BPF_REG_1, -8, 1),
    + BPF_LDX_MEM(BPF_DW, BPF_REG_0, BPF_REG_1, -8),
    + BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 1, 1),
    + BPF_MOV64_IMM(BPF_REG_0, 2),
    + BPF_EXIT_INSN(),
    + },
    + .result = ACCEPT,
    + .retval = 1,
    + .expected_insns = {
    + BACKUP_SCRATCH_REGS,
    + BPF_ALU64_IMM(BPF_ADD, BPF_REG_1, -8),
    + BPF_EMIT_CALL(INSN_IMM_MASK),
    + RESTORE_SCRATCH_REGS,
    + BPF_LDX_MEM(BPF_DW, BPF_REG_0, BPF_REG_1, -8),
    + },
    +},
    +{
    + "sanitize ldx: src is R1, dst is others, off is zero",
    + .insns = {
    + BPF_MOV64_REG(BPF_REG_1, BPF_REG_10),
    + BPF_ALU64_IMM(BPF_ADD, BPF_REG_1, -8),
    + BPF_ST_MEM(BPF_DW, BPF_REG_1, 0, 1),
    + BPF_LDX_MEM(BPF_DW, BPF_REG_1, BPF_REG_1, 0),
    + BPF_JMP_IMM(BPF_JEQ, BPF_REG_1, 1, 2),
    + BPF_MOV64_IMM(BPF_REG_0, 2),
    + BPF_EXIT_INSN(),
    + BPF_MOV64_REG(BPF_REG_0, BPF_REG_1),
    + BPF_EXIT_INSN(),
    + },
    + .result = ACCEPT,
    + .retval = 1,
    + .expected_insns = {
    + BACKUP_SCRATCH_REGS,
    + BPF_MOV64_REG(MAX_BPF_REG, BPF_REG_0),
    + BPF_EMIT_CALL(INSN_IMM_MASK),
    + RESTORE_SCRATCH_REGS,
    + BPF_MOV64_REG(BPF_REG_0, MAX_BPF_REG),
    + BPF_LDX_MEM(BPF_DW, BPF_REG_1, BPF_REG_1, 0),
    + },
    +},
    +{
    + "sanitize ldx: src is R1, dst is others",
    + .insns = {
    + BPF_MOV64_REG(BPF_REG_1, BPF_REG_10),
    + BPF_ST_MEM(BPF_DW, BPF_REG_1, -8, 1),
    + BPF_LDX_MEM(BPF_DW, BPF_REG_1, BPF_REG_1, -8),
    + BPF_JMP_IMM(BPF_JEQ, BPF_REG_1, 1, 2),
    + BPF_MOV64_IMM(BPF_REG_0, 2),
    + BPF_EXIT_INSN(),
    + BPF_MOV64_REG(BPF_REG_0, BPF_REG_1),
    + BPF_EXIT_INSN(),
    + },
    + .result = ACCEPT,
    + .retval = 1,
    + .expected_insns = {
    + BACKUP_SCRATCH_REGS,
    + BPF_MOV64_REG(MAX_BPF_REG, BPF_REG_0),
    + BPF_ALU64_IMM(BPF_ADD, BPF_REG_1, -8),
    + BPF_EMIT_CALL(INSN_IMM_MASK),
    + RESTORE_SCRATCH_REGS,
    + BPF_MOV64_REG(BPF_REG_0, MAX_BPF_REG),
    + BPF_LDX_MEM(BPF_DW, BPF_REG_1, BPF_REG_1, -8),
    + },
    +},
    +{
    + "sanitize ldx: src is others, dst is R0, off is zero",
    + .insns = {
    + BPF_MOV64_REG(BPF_REG_2, BPF_REG_10),
    + BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -8),
    + BPF_ST_MEM(BPF_DW, BPF_REG_2, 0, 1),
    + BPF_LDX_MEM(BPF_DW, BPF_REG_0, BPF_REG_2, 0),
    + BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 1, 1),
    + BPF_MOV64_IMM(BPF_REG_0, 2),
    + BPF_EXIT_INSN(),
    + },
    + .result = ACCEPT,
    + .retval = 1,
    + .expected_insns = {
    + BACKUP_SCRATCH_REGS,
    + BPF_MOV64_REG(BPF_REG_1, BPF_REG_2),
    + BPF_EMIT_CALL(INSN_IMM_MASK),
    + RESTORE_SCRATCH_REGS,
    + BPF_LDX_MEM(BPF_DW, BPF_REG_0, BPF_REG_2, 0),
    + },
    +},
    +{
    + "sanitize ldx: src is others, dst is R0",
    + .insns = {
    + BPF_MOV64_REG(BPF_REG_2, BPF_REG_10),
    + BPF_ST_MEM(BPF_DW, BPF_REG_2, -8, 1),
    + BPF_LDX_MEM(BPF_DW, BPF_REG_0, BPF_REG_2, -8),
    + BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 1, 1),
    + BPF_MOV64_IMM(BPF_REG_0, 2),
    + BPF_EXIT_INSN(),
    + },
    + .result = ACCEPT,
    + .retval = 1,
    + .expected_insns = {
    + BACKUP_SCRATCH_REGS,
    + BPF_MOV64_REG(BPF_REG_1, BPF_REG_2),
    + BPF_ALU64_IMM(BPF_ADD, BPF_REG_1, -8),
    + BPF_EMIT_CALL(INSN_IMM_MASK),
    + RESTORE_SCRATCH_REGS,
    + BPF_LDX_MEM(BPF_DW, BPF_REG_0, BPF_REG_2, -8),
    + },
    +},
    +{
    + "sanitize ldx: src is others, dst is others, off is zero",
    + .insns = {
    + BPF_MOV64_REG(BPF_REG_2, BPF_REG_10),
    + BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -8),
    + BPF_ST_MEM(BPF_DW, BPF_REG_2, 0, 1),
    + BPF_LDX_MEM(BPF_DW, BPF_REG_1, BPF_REG_2, 0),
    + BPF_JMP_IMM(BPF_JEQ, BPF_REG_1, 1, 2),
    + BPF_MOV64_IMM(BPF_REG_0, 2),
    + BPF_EXIT_INSN(),
    + BPF_MOV64_REG(BPF_REG_0, BPF_REG_1),
    + BPF_EXIT_INSN(),
    + },
    + .result = ACCEPT,
    + .retval = 1,
    + .expected_insns = {
    + BACKUP_SCRATCH_REGS,
    + BPF_MOV64_REG(MAX_BPF_REG, BPF_REG_0),
    + BPF_MOV64_REG(BPF_REG_1, BPF_REG_2),
    + BPF_EMIT_CALL(INSN_IMM_MASK),
    + RESTORE_SCRATCH_REGS,
    + BPF_MOV64_REG(BPF_REG_0, MAX_BPF_REG),
    + BPF_LDX_MEM(BPF_DW, BPF_REG_1, BPF_REG_2, 0),
    + },
    +},
    +{
    + "sanitize ldx: src is others, dst is others",
    + .insns = {
    + BPF_MOV64_REG(BPF_REG_2, BPF_REG_10),
    + BPF_ST_MEM(BPF_DW, BPF_REG_2, -8, 1),
    + BPF_LDX_MEM(BPF_DW, BPF_REG_1, BPF_REG_2, -8),
    + BPF_JMP_IMM(BPF_JEQ, BPF_REG_1, 1, 2),
    + BPF_MOV64_IMM(BPF_REG_0, 2),
    + BPF_EXIT_INSN(),
    + BPF_MOV64_REG(BPF_REG_0, BPF_REG_1),
    + BPF_EXIT_INSN(),
    + },
    + .result = ACCEPT,
    + .retval = 1,
    + .expected_insns = {
    + BACKUP_SCRATCH_REGS,
    + BPF_MOV64_REG(MAX_BPF_REG, BPF_REG_0),
    + BPF_MOV64_REG(BPF_REG_1, BPF_REG_2),
    + BPF_ALU64_IMM(BPF_ADD, BPF_REG_1, -8),
    + BPF_EMIT_CALL(INSN_IMM_MASK),
    + RESTORE_SCRATCH_REGS,
    + BPF_MOV64_REG(BPF_REG_0, MAX_BPF_REG),
    + BPF_LDX_MEM(BPF_DW, BPF_REG_1, BPF_REG_2, -8),
    + },
    +},
    +{
    + "sanitize LDX: SRC is R10",
    + .insns = {
    + BPF_ST_MEM(BPF_DW, BPF_REG_10, -8, 1),
    + BPF_LDX_MEM(BPF_DW, BPF_REG_0, BPF_REG_10, -8),
    + BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 1, 1),
    + BPF_MOV64_IMM(BPF_REG_0, 2),
    + BPF_EXIT_INSN(),
    + },
    + .result = ACCEPT,
    + .retval = 1,
    + .unexpected_insns = {
    + BPF_EMIT_CALL(INSN_IMM_MASK),
    + },
    +},
    +#endif /* CONFIG_BPF_PROG_KASAN */
    --
    2.38.1
    \
     
     \ /
      Last update: 2022-11-25 13:30    [W:3.369 / U:0.020 seconds]
    ©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site