From 18b3ad90b64e9893297357608abddd26170730eb Mon Sep 17 00:00:00 2001 From: "David S. Miller" Date: Wed, 10 May 2017 11:43:51 -0700 Subject: [PATCH] bpf: Add verifier test case for alignment. Signed-off-by: David S. Miller Acked-by: Daniel Borkmann --- tools/testing/selftests/bpf/Makefile | 3 +- tools/testing/selftests/bpf/test_align.c | 417 +++++++++++++++++++++++ 2 files changed, 419 insertions(+), 1 deletion(-) create mode 100644 tools/testing/selftests/bpf/test_align.c diff --git a/tools/testing/selftests/bpf/Makefile b/tools/testing/selftests/bpf/Makefile index 91edd0566237..f92f27d8156f 100644 --- a/tools/testing/selftests/bpf/Makefile +++ b/tools/testing/selftests/bpf/Makefile @@ -11,7 +11,8 @@ endif CFLAGS += -Wall -O2 -I$(APIDIR) -I$(LIBDIR) -I$(GENDIR) $(GENFLAGS) -I../../../include LDLIBS += -lcap -lelf -TEST_GEN_PROGS = test_verifier test_tag test_maps test_lru_map test_lpm_map test_progs +TEST_GEN_PROGS = test_verifier test_tag test_maps test_lru_map test_lpm_map test_progs \ + test_align TEST_GEN_FILES = test_pkt_access.o test_xdp.o test_l4lb.o test_tcp_estats.o diff --git a/tools/testing/selftests/bpf/test_align.c b/tools/testing/selftests/bpf/test_align.c new file mode 100644 index 000000000000..9dd97948a47f --- /dev/null +++ b/tools/testing/selftests/bpf/test_align.c @@ -0,0 +1,417 @@ +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include +#include +#include +#include + +#include + +#include "../../../include/linux/filter.h" + +#ifndef ARRAY_SIZE +# define ARRAY_SIZE(x) (sizeof(x) / sizeof((x)[0])) +#endif + +#define MAX_INSNS 512 +#define MAX_MATCHES 16 + +struct bpf_align_test { + const char *descr; + struct bpf_insn insns[MAX_INSNS]; + enum { + UNDEF, + ACCEPT, + REJECT + } result; + enum bpf_prog_type prog_type; + const char *matches[MAX_MATCHES]; +}; + +static struct bpf_align_test tests[] = { + { + .descr = "mov", + .insns = { + BPF_MOV64_IMM(BPF_REG_3, 2), + BPF_MOV64_IMM(BPF_REG_3, 4), + BPF_MOV64_IMM(BPF_REG_3, 8), + BPF_MOV64_IMM(BPF_REG_3, 16), + BPF_MOV64_IMM(BPF_REG_3, 32), + BPF_MOV64_IMM(BPF_REG_0, 0), + BPF_EXIT_INSN(), + }, + .prog_type = BPF_PROG_TYPE_SCHED_CLS, + .matches = { + "1: R1=ctx R3=imm2,min_value=2,max_value=2,min_align=2 R10=fp", + "2: R1=ctx R3=imm4,min_value=4,max_value=4,min_align=4 R10=fp", + "3: R1=ctx R3=imm8,min_value=8,max_value=8,min_align=8 R10=fp", + "4: R1=ctx R3=imm16,min_value=16,max_value=16,min_align=16 R10=fp", + "5: R1=ctx R3=imm32,min_value=32,max_value=32,min_align=32 R10=fp", + }, + }, + { + .descr = "shift", + .insns = { + BPF_MOV64_IMM(BPF_REG_3, 1), + BPF_ALU64_IMM(BPF_LSH, BPF_REG_3, 1), + BPF_ALU64_IMM(BPF_LSH, BPF_REG_3, 1), + BPF_ALU64_IMM(BPF_LSH, BPF_REG_3, 1), + BPF_ALU64_IMM(BPF_LSH, BPF_REG_3, 1), + BPF_ALU64_IMM(BPF_RSH, BPF_REG_3, 4), + BPF_MOV64_IMM(BPF_REG_4, 32), + BPF_ALU64_IMM(BPF_RSH, BPF_REG_4, 1), + BPF_ALU64_IMM(BPF_RSH, BPF_REG_4, 1), + BPF_ALU64_IMM(BPF_RSH, BPF_REG_4, 1), + BPF_ALU64_IMM(BPF_RSH, BPF_REG_4, 1), + BPF_MOV64_IMM(BPF_REG_0, 0), + BPF_EXIT_INSN(), + }, + .prog_type = BPF_PROG_TYPE_SCHED_CLS, + .matches = { + "1: R1=ctx R3=imm1,min_value=1,max_value=1,min_align=1 R10=fp", + "2: R1=ctx R3=imm2,min_value=2,max_value=2,min_align=2 R10=fp", + "3: R1=ctx R3=imm4,min_value=4,max_value=4,min_align=4 R10=fp", + "4: R1=ctx R3=imm8,min_value=8,max_value=8,min_align=8 R10=fp", + "5: R1=ctx R3=imm16,min_value=16,max_value=16,min_align=16 R10=fp", + "6: R1=ctx R3=imm1,min_value=1,max_value=1,min_align=1 R10=fp", + "7: R1=ctx R3=imm1,min_value=1,max_value=1,min_align=1 R4=imm32,min_value=32,max_value=32,min_align=32 R10=fp", + "8: R1=ctx R3=imm1,min_value=1,max_value=1,min_align=1 R4=imm16,min_value=16,max_value=16,min_align=16 R10=fp", + "9: R1=ctx R3=imm1,min_value=1,max_value=1,min_align=1 R4=imm8,min_value=8,max_value=8,min_align=8 R10=fp", + "10: R1=ctx R3=imm1,min_value=1,max_value=1,min_align=1 R4=imm4,min_value=4,max_value=4,min_align=4 R10=fp", + "11: R1=ctx R3=imm1,min_value=1,max_value=1,min_align=1 R4=imm2,min_value=2,max_value=2,min_align=2 R10=fp", + }, + }, + { + .descr = "addsub", + .insns = { + BPF_MOV64_IMM(BPF_REG_3, 4), + BPF_ALU64_IMM(BPF_ADD, BPF_REG_3, 4), + BPF_ALU64_IMM(BPF_ADD, BPF_REG_3, 2), + BPF_MOV64_IMM(BPF_REG_4, 8), + BPF_ALU64_IMM(BPF_ADD, BPF_REG_4, 4), + BPF_ALU64_IMM(BPF_ADD, BPF_REG_4, 2), + BPF_MOV64_IMM(BPF_REG_0, 0), + BPF_EXIT_INSN(), + }, + .prog_type = BPF_PROG_TYPE_SCHED_CLS, + .matches = { + "1: R1=ctx R3=imm4,min_value=4,max_value=4,min_align=4 R10=fp", + "2: R1=ctx R3=imm8,min_value=8,max_value=8,min_align=4 R10=fp", + "3: R1=ctx R3=imm10,min_value=10,max_value=10,min_align=2 R10=fp", + "4: R1=ctx R3=imm10,min_value=10,max_value=10,min_align=2 R4=imm8,min_value=8,max_value=8,min_align=8 R10=fp", + "5: R1=ctx R3=imm10,min_value=10,max_value=10,min_align=2 R4=imm12,min_value=12,max_value=12,min_align=4 R10=fp", + "6: R1=ctx R3=imm10,min_value=10,max_value=10,min_align=2 R4=imm14,min_value=14,max_value=14,min_align=2 R10=fp", + }, + }, + { + .descr = "mul", + .insns = { + BPF_MOV64_IMM(BPF_REG_3, 7), + BPF_ALU64_IMM(BPF_MUL, BPF_REG_3, 1), + BPF_ALU64_IMM(BPF_MUL, BPF_REG_3, 2), + BPF_ALU64_IMM(BPF_MUL, BPF_REG_3, 4), + BPF_MOV64_IMM(BPF_REG_0, 0), + BPF_EXIT_INSN(), + }, + .prog_type = BPF_PROG_TYPE_SCHED_CLS, + .matches = { + "1: R1=ctx R3=imm7,min_value=7,max_value=7,min_align=1 R10=fp", + "2: R1=ctx R3=imm7,min_value=7,max_value=7,min_align=1 R10=fp", + "3: R1=ctx R3=imm14,min_value=14,max_value=14,min_align=2 R10=fp", + "4: R1=ctx R3=imm56,min_value=56,max_value=56,min_align=4 R10=fp", + }, + }, + +#define PREP_PKT_POINTERS \ + BPF_LDX_MEM(BPF_W, BPF_REG_2, BPF_REG_1, \ + offsetof(struct __sk_buff, data)), \ + BPF_LDX_MEM(BPF_W, BPF_REG_3, BPF_REG_1, \ + offsetof(struct __sk_buff, data_end)) + +#define LOAD_UNKNOWN(DST_REG) \ + PREP_PKT_POINTERS, \ + BPF_MOV64_REG(BPF_REG_0, BPF_REG_2), \ + BPF_ALU64_IMM(BPF_ADD, BPF_REG_0, 8), \ + BPF_JMP_REG(BPF_JGE, BPF_REG_3, BPF_REG_0, 1), \ + BPF_EXIT_INSN(), \ + BPF_LDX_MEM(BPF_B, DST_REG, BPF_REG_2, 0) + + { + .descr = "unknown shift", + .insns = { + LOAD_UNKNOWN(BPF_REG_3), + BPF_ALU64_IMM(BPF_LSH, BPF_REG_3, 1), + BPF_ALU64_IMM(BPF_LSH, BPF_REG_3, 1), + BPF_ALU64_IMM(BPF_LSH, BPF_REG_3, 1), + BPF_ALU64_IMM(BPF_LSH, BPF_REG_3, 1), + LOAD_UNKNOWN(BPF_REG_4), + BPF_ALU64_IMM(BPF_LSH, BPF_REG_4, 5), + BPF_ALU64_IMM(BPF_RSH, BPF_REG_4, 1), + BPF_ALU64_IMM(BPF_RSH, BPF_REG_4, 1), + BPF_ALU64_IMM(BPF_RSH, BPF_REG_4, 1), + BPF_ALU64_IMM(BPF_RSH, BPF_REG_4, 1), + BPF_MOV64_IMM(BPF_REG_0, 0), + BPF_EXIT_INSN(), + }, + .prog_type = BPF_PROG_TYPE_SCHED_CLS, + .matches = { + "7: R0=pkt(id=0,off=8,r=8) R1=ctx R2=pkt(id=0,off=0,r=8) R3=inv56 R10=fp", + "8: R0=pkt(id=0,off=8,r=8) R1=ctx R2=pkt(id=0,off=0,r=8) R3=inv55,min_align=2 R10=fp", + "9: R0=pkt(id=0,off=8,r=8) R1=ctx R2=pkt(id=0,off=0,r=8) R3=inv54,min_align=4 R10=fp", + "10: R0=pkt(id=0,off=8,r=8) R1=ctx R2=pkt(id=0,off=0,r=8) R3=inv53,min_align=8 R10=fp", + "11: R0=pkt(id=0,off=8,r=8) R1=ctx R2=pkt(id=0,off=0,r=8) R3=inv52,min_align=16 R10=fp", + "18: R0=pkt(id=0,off=8,r=8) R1=ctx R2=pkt(id=0,off=0,r=8) R3=pkt_end R4=inv56 R10=fp", + "19: R0=pkt(id=0,off=8,r=8) R1=ctx R2=pkt(id=0,off=0,r=8) R3=pkt_end R4=inv51,min_align=32 R10=fp", + "20: R0=pkt(id=0,off=8,r=8) R1=ctx R2=pkt(id=0,off=0,r=8) R3=pkt_end R4=inv52,min_align=16 R10=fp", + "21: R0=pkt(id=0,off=8,r=8) R1=ctx R2=pkt(id=0,off=0,r=8) R3=pkt_end R4=inv53,min_align=8 R10=fp", + "22: R0=pkt(id=0,off=8,r=8) R1=ctx R2=pkt(id=0,off=0,r=8) R3=pkt_end R4=inv54,min_align=4 R10=fp", + "23: R0=pkt(id=0,off=8,r=8) R1=ctx R2=pkt(id=0,off=0,r=8) R3=pkt_end R4=inv55,min_align=2 R10=fp", + }, + }, + { + .descr = "unknown mul", + .insns = { + LOAD_UNKNOWN(BPF_REG_3), + BPF_MOV64_REG(BPF_REG_4, BPF_REG_3), + BPF_ALU64_IMM(BPF_MUL, BPF_REG_4, 1), + BPF_MOV64_REG(BPF_REG_4, BPF_REG_3), + BPF_ALU64_IMM(BPF_MUL, BPF_REG_4, 2), + BPF_MOV64_REG(BPF_REG_4, BPF_REG_3), + BPF_ALU64_IMM(BPF_MUL, BPF_REG_4, 4), + BPF_MOV64_REG(BPF_REG_4, BPF_REG_3), + BPF_ALU64_IMM(BPF_MUL, BPF_REG_4, 8), + BPF_ALU64_IMM(BPF_MUL, BPF_REG_4, 2), + BPF_MOV64_IMM(BPF_REG_0, 0), + BPF_EXIT_INSN(), + }, + .prog_type = BPF_PROG_TYPE_SCHED_CLS, + .matches = { + "7: R0=pkt(id=0,off=8,r=8) R1=ctx R2=pkt(id=0,off=0,r=8) R3=inv56 R10=fp", + "8: R0=pkt(id=0,off=8,r=8) R1=ctx R2=pkt(id=0,off=0,r=8) R3=inv56 R4=inv56 R10=fp", + "9: R0=pkt(id=0,off=8,r=8) R1=ctx R2=pkt(id=0,off=0,r=8) R3=inv56 R4=inv55,min_align=1 R10=fp", + "10: R0=pkt(id=0,off=8,r=8) R1=ctx R2=pkt(id=0,off=0,r=8) R3=inv56 R4=inv56 R10=fp", + "11: R0=pkt(id=0,off=8,r=8) R1=ctx R2=pkt(id=0,off=0,r=8) R3=inv56 R4=inv54,min_align=2 R10=fp", + "12: R0=pkt(id=0,off=8,r=8) R1=ctx R2=pkt(id=0,off=0,r=8) R3=inv56 R4=inv56 R10=fp", + "13: R0=pkt(id=0,off=8,r=8) R1=ctx R2=pkt(id=0,off=0,r=8) R3=inv56 R4=inv53,min_align=4 R10=fp", + "14: R0=pkt(id=0,off=8,r=8) R1=ctx R2=pkt(id=0,off=0,r=8) R3=inv56 R4=inv56 R10=fp", + "15: R0=pkt(id=0,off=8,r=8) R1=ctx R2=pkt(id=0,off=0,r=8) R3=inv56 R4=inv52,min_align=8 R10=fp", + "16: R0=pkt(id=0,off=8,r=8) R1=ctx R2=pkt(id=0,off=0,r=8) R3=inv56 R4=inv50,min_align=8 R10=fp" + }, + }, + { + .descr = "packet const offset", + .insns = { + PREP_PKT_POINTERS, + BPF_MOV64_REG(BPF_REG_5, BPF_REG_2), + + BPF_MOV64_IMM(BPF_REG_0, 0), + + /* Skip over ethernet header. */ + BPF_ALU64_IMM(BPF_ADD, BPF_REG_5, 14), + BPF_MOV64_REG(BPF_REG_4, BPF_REG_5), + BPF_ALU64_IMM(BPF_ADD, BPF_REG_4, 4), + BPF_JMP_REG(BPF_JGE, BPF_REG_3, BPF_REG_4, 1), + BPF_EXIT_INSN(), + + BPF_LDX_MEM(BPF_B, BPF_REG_4, BPF_REG_5, 0), + BPF_LDX_MEM(BPF_B, BPF_REG_4, BPF_REG_5, 1), + BPF_LDX_MEM(BPF_B, BPF_REG_4, BPF_REG_5, 2), + BPF_LDX_MEM(BPF_B, BPF_REG_4, BPF_REG_5, 3), + BPF_LDX_MEM(BPF_H, BPF_REG_4, BPF_REG_5, 0), + BPF_LDX_MEM(BPF_H, BPF_REG_4, BPF_REG_5, 2), + BPF_LDX_MEM(BPF_W, BPF_REG_4, BPF_REG_5, 0), + + BPF_MOV64_IMM(BPF_REG_0, 0), + BPF_EXIT_INSN(), + }, + .prog_type = BPF_PROG_TYPE_SCHED_CLS, + .matches = { + "4: R0=imm0,min_value=0,max_value=0,min_align=2147483648 R1=ctx R2=pkt(id=0,off=0,r=0) R3=pkt_end R5=pkt(id=0,off=0,r=0) R10=fp", + "5: R0=imm0,min_value=0,max_value=0,min_align=2147483648 R1=ctx R2=pkt(id=0,off=0,r=0) R3=pkt_end R5=pkt(id=0,off=14,r=0) R10=fp", + "6: R0=imm0,min_value=0,max_value=0,min_align=2147483648 R1=ctx R2=pkt(id=0,off=0,r=0) R3=pkt_end R4=pkt(id=0,off=14,r=0) R5=pkt(id=0,off=14,r=0) R10=fp", + "10: R0=imm0,min_value=0,max_value=0,min_align=2147483648 R1=ctx R2=pkt(id=0,off=0,r=18) R3=pkt_end R4=inv56 R5=pkt(id=0,off=14,r=18) R10=fp", + "14: R0=imm0,min_value=0,max_value=0,min_align=2147483648 R1=ctx R2=pkt(id=0,off=0,r=18) R3=pkt_end R4=inv48 R5=pkt(id=0,off=14,r=18) R10=fp", + "15: R0=imm0,min_value=0,max_value=0,min_align=2147483648 R1=ctx R2=pkt(id=0,off=0,r=18) R3=pkt_end R4=inv48 R5=pkt(id=0,off=14,r=18) R10=fp", + }, + }, + { + .descr = "packet variable offset", + .insns = { + LOAD_UNKNOWN(BPF_REG_6), + BPF_ALU64_IMM(BPF_LSH, BPF_REG_6, 2), + + /* First, add a constant to the R5 packet pointer, + * then a variable with a known alignment. + */ + BPF_MOV64_REG(BPF_REG_5, BPF_REG_2), + BPF_ALU64_IMM(BPF_ADD, BPF_REG_5, 14), + BPF_ALU64_REG(BPF_ADD, BPF_REG_5, BPF_REG_6), + BPF_MOV64_REG(BPF_REG_4, BPF_REG_5), + BPF_ALU64_IMM(BPF_ADD, BPF_REG_4, 4), + BPF_JMP_REG(BPF_JGE, BPF_REG_3, BPF_REG_4, 1), + BPF_EXIT_INSN(), + BPF_LDX_MEM(BPF_W, BPF_REG_4, BPF_REG_5, 0), + + /* Now, test in the other direction. Adding first + * the variable offset to R5, then the constant. + */ + BPF_MOV64_REG(BPF_REG_5, BPF_REG_2), + BPF_ALU64_REG(BPF_ADD, BPF_REG_5, BPF_REG_6), + BPF_ALU64_IMM(BPF_ADD, BPF_REG_5, 14), + BPF_MOV64_REG(BPF_REG_4, BPF_REG_5), + BPF_ALU64_IMM(BPF_ADD, BPF_REG_4, 4), + BPF_JMP_REG(BPF_JGE, BPF_REG_3, BPF_REG_4, 1), + BPF_EXIT_INSN(), + BPF_LDX_MEM(BPF_W, BPF_REG_4, BPF_REG_5, 0), + + BPF_MOV64_IMM(BPF_REG_0, 0), + BPF_EXIT_INSN(), + }, + .prog_type = BPF_PROG_TYPE_SCHED_CLS, + .matches = { + /* Calculated offset in R6 has unknown value, but known + * alignment of 4. + */ + "8: R0=pkt(id=0,off=8,r=8) R1=ctx R2=pkt(id=0,off=0,r=8) R3=pkt_end R6=inv54,min_align=4 R10=fp", + + /* Offset is added to packet pointer R5, resulting in known + * auxiliary alignment and offset. + */ + "11: R0=pkt(id=0,off=8,r=8) R1=ctx R2=pkt(id=0,off=0,r=8) R3=pkt_end R5=pkt(id=1,off=0,r=0),aux_off=14,aux_off_align=4 R6=inv54,min_align=4 R10=fp", + + /* At the time the word size load is performed from R5, + * it's total offset is NET_IP_ALIGN + reg->off (0) + + * reg->aux_off (14) which is 16. Then the variable + * offset is considered using reg->aux_off_align which + * is 4 and meets the load's requirements. + */ + "15: R0=pkt(id=0,off=8,r=8) R1=ctx R2=pkt(id=0,off=0,r=8) R3=pkt_end R4=pkt(id=1,off=4,r=4),aux_off=14,aux_off_align=4 R5=pkt(id=1,off=0,r=4),aux_off=14,aux_off_align=4 R6=inv54,min_align=4 R10=fp", + + + /* Variable offset is added to R5 packet pointer, + * resulting in auxiliary alignment of 4. + */ + "18: R0=pkt(id=0,off=8,r=8) R1=ctx R2=pkt(id=0,off=0,r=8) R3=pkt_end R4=inv,aux_off=14,aux_off_align=4 R5=pkt(id=2,off=0,r=0),aux_off_align=4 R6=inv54,min_align=4 R10=fp", + + /* Constant offset is added to R5, resulting in + * reg->off of 14. + */ + "19: R0=pkt(id=0,off=8,r=8) R1=ctx R2=pkt(id=0,off=0,r=8) R3=pkt_end R4=inv,aux_off=14,aux_off_align=4 R5=pkt(id=2,off=14,r=0),aux_off_align=4 R6=inv54,min_align=4 R10=fp", + + /* At the time the word size load is performed from R5, + * it's total offset is NET_IP_ALIGN + reg->off (14) which + * is 16. Then the variable offset is considered using + * reg->aux_off_align which is 4 and meets the load's + * requirements. + */ + "23: R0=pkt(id=0,off=8,r=8) R1=ctx R2=pkt(id=0,off=0,r=8) R3=pkt_end R4=pkt(id=2,off=18,r=18),aux_off_align=4 R5=pkt(id=2,off=14,r=18),aux_off_align=4 R6=inv54,min_align=4 R10=fp", + }, + }, +}; + +static int probe_filter_length(const struct bpf_insn *fp) +{ + int len; + + for (len = MAX_INSNS - 1; len > 0; --len) + if (fp[len].code != 0 || fp[len].imm != 0) + break; + return len + 1; +} + +static char bpf_vlog[32768]; + +static int do_test_single(struct bpf_align_test *test) +{ + struct bpf_insn *prog = test->insns; + int prog_type = test->prog_type; + int prog_len, i; + int fd_prog; + int ret; + + prog_len = probe_filter_length(prog); + fd_prog = bpf_verify_program(prog_type ? : BPF_PROG_TYPE_SOCKET_FILTER, + prog, prog_len, 1, "GPL", 0, + bpf_vlog, sizeof(bpf_vlog)); + if (fd_prog < 0) { + printf("Failed to load program.\n"); + printf("%s", bpf_vlog); + ret = 1; + } else { + ret = 0; + for (i = 0; i < MAX_MATCHES; i++) { + const char *t, *m = test->matches[i]; + + if (!m) + break; + t = strstr(bpf_vlog, m); + if (!t) { + printf("Failed to find match: %s\n", m); + ret = 1; + printf("%s", bpf_vlog); + break; + } + } + /* printf("%s", bpf_vlog); */ + close(fd_prog); + } + return ret; +} + +static int do_test(unsigned int from, unsigned int to) +{ + int all_pass = 0; + int all_fail = 0; + unsigned int i; + + for (i = from; i < to; i++) { + struct bpf_align_test *test = &tests[i]; + int fail; + + printf("Test %3d: %s ... ", + i, test->descr); + fail = do_test_single(test); + if (fail) { + all_fail++; + printf("FAIL\n"); + } else { + all_pass++; + printf("PASS\n"); + } + } + printf("Results: %d pass %d fail\n", + all_pass, all_fail); + return 0; +} + +int main(int argc, char **argv) +{ + unsigned int from = 0, to = ARRAY_SIZE(tests); + + if (argc == 3) { + unsigned int l = atoi(argv[argc - 2]); + unsigned int u = atoi(argv[argc - 1]); + + if (l < to && u < to) { + from = l; + to = u + 1; + } + } else if (argc == 2) { + unsigned int t = atoi(argv[argc - 1]); + + if (t < to) { + from = t; + to = t + 1; + } + } + return do_test(from, to); +} -- 2.20.1