diff options
Diffstat (limited to 'tools')
| -rw-r--r-- | tools/testing/selftests/bpf/progs/verifier_bounds.c | 137 |
1 files changed, 137 insertions, 0 deletions
diff --git a/tools/testing/selftests/bpf/progs/verifier_bounds.c b/tools/testing/selftests/bpf/progs/verifier_bounds.c index 560531404bce..97065a26cf70 100644 --- a/tools/testing/selftests/bpf/progs/verifier_bounds.c +++ b/tools/testing/selftests/bpf/progs/verifier_bounds.c @@ -1863,4 +1863,141 @@ l1_%=: r0 = 1; \ : __clobber_all); } +/* This test covers the bounds deduction when the u64 range and the tnum + * overlap only at umax. After instruction 3, the ranges look as follows: + * + * 0 umin=0xe01 umax=0xf00 U64_MAX + * | [xxxxxxxxxxxxxx] | + * |----------------------------|------------------------------| + * | x x | tnum values + * + * The verifier can therefore deduce that the R0=0xf0=240. + */ +SEC("socket") +__description("bounds refinement with single-value tnum on umax") +__msg("3: (15) if r0 == 0xe0 {{.*}} R0=240") +__success __log_level(2) +__flag(BPF_F_TEST_REG_INVARIANTS) +__naked void bounds_refinement_tnum_umax(void *ctx) +{ + asm volatile(" \ + call %[bpf_get_prandom_u32]; \ + r0 |= 0xe0; \ + r0 &= 0xf0; \ + if r0 == 0xe0 goto +2; \ + if r0 == 0xf0 goto +1; \ + r10 = 0; \ + exit; \ +" : + : __imm(bpf_get_prandom_u32) + : __clobber_all); +} + +/* This test covers the bounds deduction when the u64 range and the tnum + * overlap only at umin. After instruction 3, the ranges look as follows: + * + * 0 umin=0xe00 umax=0xeff U64_MAX + * | [xxxxxxxxxxxxxx] | + * |----------------------------|------------------------------| + * | x x | tnum values + * + * The verifier can therefore deduce that the R0=0xe0=224. + */ +SEC("socket") +__description("bounds refinement with single-value tnum on umin") +__msg("3: (15) if r0 == 0xf0 {{.*}} R0=224") +__success __log_level(2) +__flag(BPF_F_TEST_REG_INVARIANTS) +__naked void bounds_refinement_tnum_umin(void *ctx) +{ + asm volatile(" \ + call %[bpf_get_prandom_u32]; \ + r0 |= 0xe0; \ + r0 &= 0xf0; \ + if r0 == 0xf0 goto +2; \ + if r0 == 0xe0 goto +1; \ + r10 = 0; \ + exit; \ +" : + : __imm(bpf_get_prandom_u32) + : __clobber_all); +} + +/* This test covers the bounds deduction when the only possible tnum value is + * in the middle of the u64 range. After instruction 3, the ranges look as + * follows: + * + * 0 umin=0x7cf umax=0x7df U64_MAX + * | [xxxxxxxxxxxx] | + * |----------------------------|------------------------------| + * | x x x x x | tnum values + * | +--- 0x7e0 + * +--- 0x7d0 + * + * Since the lower four bits are zero, the tnum and the u64 range only overlap + * in R0=0x7d0=2000. Instruction 5 is therefore dead code. + */ +SEC("socket") +__description("bounds refinement with single-value tnum in middle of range") +__msg("3: (a5) if r0 < 0x7cf {{.*}} R0=2000") +__success __log_level(2) +__naked void bounds_refinement_tnum_middle(void *ctx) +{ + asm volatile(" \ + call %[bpf_get_prandom_u32]; \ + if r0 & 0x0f goto +4; \ + if r0 > 0x7df goto +3; \ + if r0 < 0x7cf goto +2; \ + if r0 == 0x7d0 goto +1; \ + r10 = 0; \ + exit; \ +" : + : __imm(bpf_get_prandom_u32) + : __clobber_all); +} + +/* This test cover the negative case for the tnum/u64 overlap. Since + * they contain the same two values (i.e., {0, 1}), we can't deduce + * anything more. + */ +SEC("socket") +__description("bounds refinement: several overlaps between tnum and u64") +__msg("2: (25) if r0 > 0x1 {{.*}} R0=scalar(smin=smin32=0,smax=umax=smax32=umax32=1,var_off=(0x0; 0x1))") +__failure __log_level(2) +__naked void bounds_refinement_several_overlaps(void *ctx) +{ + asm volatile(" \ + call %[bpf_get_prandom_u32]; \ + if r0 < 0 goto +3; \ + if r0 > 1 goto +2; \ + if r0 == 1 goto +1; \ + r10 = 0; \ + exit; \ +" : + : __imm(bpf_get_prandom_u32) + : __clobber_all); +} + +/* This test cover the negative case for the tnum/u64 overlap. Since + * they overlap in the two values contained by the u64 range (i.e., + * {0xf, 0x10}), we can't deduce anything more. + */ +SEC("socket") +__description("bounds refinement: multiple overlaps between tnum and u64") +__msg("2: (25) if r0 > 0x10 {{.*}} R0=scalar(smin=umin=smin32=umin32=15,smax=umax=smax32=umax32=16,var_off=(0x0; 0x1f))") +__failure __log_level(2) +__naked void bounds_refinement_multiple_overlaps(void *ctx) +{ + asm volatile(" \ + call %[bpf_get_prandom_u32]; \ + if r0 < 0xf goto +3; \ + if r0 > 0x10 goto +2; \ + if r0 == 0x10 goto +1; \ + r10 = 0; \ + exit; \ +" : + : __imm(bpf_get_prandom_u32) + : __clobber_all); +} + char _license[] SEC("license") = "GPL"; |