From: Alexei Starovoitov <ast@kernel.org>
Date: Tue, 3 Sep 2019 15:51:33 -0700
Subject: selftests/bpf: precision tracking tests
Patch-mainline: v5.4-rc1
Git-commit: 310f4204eeb6053e35c277a23d9c179e8e32322e
References: bsc#1177028
Add two tests to check that stack slot marking during backtracking
doesn't trigger 'spi > allocated_stack' warning.
One test is using BPF_ST insn. Another is using BPF_STX.
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Gary Lin <glin@suse.com>
---
tools/testing/selftests/bpf/verifier/precise.c | 52 +++++++++++++++++++++++++
1 file changed, 52 insertions(+)
--- a/tools/testing/selftests/bpf/verifier/precise.c
+++ b/tools/testing/selftests/bpf/verifier/precise.c
@@ -140,3 +140,55 @@
.errstr = "!read_ok",
.result = REJECT,
},
+{
+ "precise: ST insn causing spi > allocated_stack",
+ .insns = {
+ BPF_MOV64_REG(BPF_REG_3, BPF_REG_10),
+ BPF_JMP_IMM(BPF_JNE, BPF_REG_3, 123, 0),
+ BPF_ST_MEM(BPF_DW, BPF_REG_3, -8, 0),
+ BPF_LDX_MEM(BPF_DW, BPF_REG_4, BPF_REG_10, -8),
+ BPF_MOV64_IMM(BPF_REG_0, -1),
+ BPF_JMP_REG(BPF_JGT, BPF_REG_4, BPF_REG_0, 0),
+ BPF_EXIT_INSN(),
+ },
+ .prog_type = BPF_PROG_TYPE_XDP,
+ .flags = BPF_F_TEST_STATE_FREQ,
+ .errstr = "5: (2d) if r4 > r0 goto pc+0\
+ last_idx 5 first_idx 5\
+ parent didn't have regs=10 stack=0 marks\
+ last_idx 4 first_idx 2\
+ regs=10 stack=0 before 4\
+ regs=10 stack=0 before 3\
+ regs=0 stack=1 before 2\
+ last_idx 5 first_idx 5\
+ parent didn't have regs=1 stack=0 marks",
+ .result = VERBOSE_ACCEPT,
+ .retval = -1,
+},
+{
+ "precise: STX insn causing spi > allocated_stack",
+ .insns = {
+ BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_get_prandom_u32),
+ BPF_MOV64_REG(BPF_REG_3, BPF_REG_10),
+ BPF_JMP_IMM(BPF_JNE, BPF_REG_3, 123, 0),
+ BPF_STX_MEM(BPF_DW, BPF_REG_3, BPF_REG_0, -8),
+ BPF_LDX_MEM(BPF_DW, BPF_REG_4, BPF_REG_10, -8),
+ BPF_MOV64_IMM(BPF_REG_0, -1),
+ BPF_JMP_REG(BPF_JGT, BPF_REG_4, BPF_REG_0, 0),
+ BPF_EXIT_INSN(),
+ },
+ .prog_type = BPF_PROG_TYPE_XDP,
+ .flags = BPF_F_TEST_STATE_FREQ,
+ .errstr = "last_idx 6 first_idx 6\
+ parent didn't have regs=10 stack=0 marks\
+ last_idx 5 first_idx 3\
+ regs=10 stack=0 before 5\
+ regs=10 stack=0 before 4\
+ regs=0 stack=1 before 3\
+ last_idx 6 first_idx 6\
+ parent didn't have regs=1 stack=0 marks\
+ last_idx 5 first_idx 3\
+ regs=1 stack=0 before 5",
+ .result = VERBOSE_ACCEPT,
+ .retval = -1,
+},