selftests/bpf: Add test for sign extension in coerce_subreg_to_size_sx()

Add a test for unsigned ranges after signed extension instruction. This
case isn't currently covered by existing tests in verifier_movsx.c.

Acked-by: Shung-Hsi Yu <shung-hsi.yu@suse.com>
Signed-off-by: Dimitar Kanaliev <dimitar.kanaliev@siteground.com>
Acked-by: Yonghong Song <yonghong.song@linux.dev>
Link: https://lore.kernel.org/r/20241014121155.92887-4-dimitar.kanaliev@siteground.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
This commit is contained in:
Dimitar Kanaliev 2024-10-14 15:11:55 +03:00 committed by Alexei Starovoitov
parent 61f506eacc
commit 35ccd576a2

View File

@ -307,6 +307,26 @@ label_%=: \
: __clobber_all);
}
SEC("socket")
__description("MOV32SX, S8, unsigned range_check")
__success __retval(0)
__naked void mov32sx_s8_range_check(void)
{
asm volatile (" \
call %[bpf_get_prandom_u32]; \
w0 &= 0x1; \
w0 += 0xfe; \
w0 = (s8)w0; \
if w0 < 0xfffffffe goto label_%=; \
r0 = 0; \
exit; \
label_%=: \
exit; \
" :
: __imm(bpf_get_prandom_u32)
: __clobber_all);
}
#else
SEC("socket")