Added a test for bound computation in MUL when non constant values are used and both registers have bounded ranges. Signed-off-by: Cupertino Miranda <cupertino.miranda@xxxxxxxxxx> Acked-by: Eduard Zingerman <eddyz87@xxxxxxxxx> Acked-by: Andrii Nakryiko <andrii.nakryiko@xxxxxxxxx> Cc: Yonghong Song <yonghong.song@xxxxxxxxx> Cc: Alexei Starovoitov <alexei.starovoitov@xxxxxxxxx> Cc: David Faust <david.faust@xxxxxxxxxx> Cc: Jose Marchesi <jose.marchesi@xxxxxxxxxx> Cc: Elena Zannoni <elena.zannoni@xxxxxxxxxx> --- .../selftests/bpf/progs/verifier_bounds.c | 21 +++++++++++++++++++ 1 file changed, 21 insertions(+) diff --git a/tools/testing/selftests/bpf/progs/verifier_bounds.c b/tools/testing/selftests/bpf/progs/verifier_bounds.c index 7d570acf23ee..a0bb7fb40ea5 100644 --- a/tools/testing/selftests/bpf/progs/verifier_bounds.c +++ b/tools/testing/selftests/bpf/progs/verifier_bounds.c @@ -927,6 +927,27 @@ __naked void non_const_or_src_dst(void) : __clobber_all); } +SEC("socket") +__description("bounds check for non const mul regs") +__success __log_level(2) +__msg("5: (2f) r0 *= r6 ; R0_w=scalar(smin=smin32=0,smax=umax=smax32=umax32=3825,var_off=(0x0; 0xfff))") +__naked void non_const_mul_regs(void) +{ + asm volatile (" \ + call %[bpf_get_prandom_u32]; \ + r6 = r0; \ + call %[bpf_get_prandom_u32]; \ + r6 &= 0xff; \ + r0 &= 0x0f; \ + r0 *= r6; \ + exit; \ +" : + : __imm(bpf_map_lookup_elem), + __imm_addr(map_hash_8b), + __imm(bpf_get_prandom_u32) + : __clobber_all); +} + SEC("socket") __description("bounds checks after 32-bit truncation. test 1") __success __failure_unpriv __msg_unpriv("R0 leaks addr") -- 2.39.2