Commit 310f4204 authored by Alexei Starovoitov's avatar Alexei Starovoitov Committed by Daniel Borkmann
Browse files

selftests/bpf: precision tracking tests 



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: default avatarAlexei Starovoitov <ast@kernel.org>
Signed-off-by: default avatarDaniel Borkmann <daniel@iogearbox.net>
parent 7cbbf9f1

tools/testing/selftests/bpf/verifier/precise.c

+52 −0
Original line number Diff line number Diff line
@@ -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,

},

CRA Git | Maintained and supported by SUSTech CRA and CCSE