#include #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), /* Test multiple accumulations of unknown values * into a packet pointer. */ 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_ALU64_IMM(BPF_ADD, BPF_REG_5, 4), 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), 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", /* Constant offset is added to R5 packet pointer, * resulting in reg->off value of 14. */ "26: 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_align=4 R5=pkt(id=0,off=14,r=8) R6=inv54,min_align=4 R10=fp", /* Variable offset is added to R5, resulting in an * auxiliary offset of 14, and an auxiliary alignment of 4. */ "27: 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_align=4 R5=pkt(id=3,off=0,r=0),aux_off=14,aux_off_align=4 R6=inv54,min_align=4 R10=fp", /* Constant is added to R5 again, setting reg->off to 4. */ "28: 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_align=4 R5=pkt(id=3,off=4,r=0),aux_off=14,aux_off_align=4 R6=inv54,min_align=4 R10=fp", /* And once more we add a variable, which causes an accumulation * of reg->off into reg->aux_off_align, with resulting value of * 18. The auxiliary alignment stays at 4. */ "29: 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_align=4 R5=pkt(id=4,off=0,r=0),aux_off=18,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 (18) which is 20. Then the variable offset * is considered using reg->aux_off_align which is 4 and meets * the load's requirements. */ "33: R0=pkt(id=0,off=8,r=8) R1=ctx R2=pkt(id=0,off=0,r=8) R3=pkt_end R4=pkt(id=4,off=4,r=4),aux_off=18,aux_off_align=4 R5=pkt(id=4,off=0,r=4),aux_off=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; } } 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 all_fail ? EXIT_FAILURE : EXIT_SUCCESS; } int main(int argc, char **argv) { unsigned int from = 0, to = ARRAY_SIZE(tests); struct rlimit rinf = { RLIM_INFINITY, RLIM_INFINITY }; setrlimit(RLIMIT_MEMLOCK, &rinf); 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); }