selftests/bpf: Tests with may_goto and jumps to the 1st insn

Add few tests with may_goto and jumps to the 1st insn.

Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Eduard Zingerman <eddyz87@gmail.com>
Link: https://lore.kernel.org/bpf/20240619011859.79334-2-alexei.starovoitov@gmail.com
This commit is contained in:
Alexei Starovoitov 2024-06-18 18:18:59 -07:00 committed by Daniel Borkmann
parent 5337ac4c9b
commit 2673315947

View File

@ -307,6 +307,100 @@ int iter_limit_bug(struct __sk_buff *skb)
return 0;
}
SEC("socket")
__success __retval(0)
__naked void ja_and_may_goto(void)
{
asm volatile (" \
l0_%=: .byte 0xe5; /* may_goto */ \
.byte 0; /* regs */ \
.short 1; /* off 1 */ \
.long 0; /* imm */ \
goto l0_%=; \
r0 = 0; \
exit; \
" ::: __clobber_common);
}
SEC("socket")
__success __retval(0)
__naked void ja_and_may_goto2(void)
{
asm volatile (" \
l0_%=: r0 = 0; \
.byte 0xe5; /* may_goto */ \
.byte 0; /* regs */ \
.short 1; /* off 1 */ \
.long 0; /* imm */ \
goto l0_%=; \
r0 = 0; \
exit; \
" ::: __clobber_common);
}
SEC("socket")
__success __retval(0)
__naked void jlt_and_may_goto(void)
{
asm volatile (" \
l0_%=: call %[bpf_jiffies64]; \
.byte 0xe5; /* may_goto */ \
.byte 0; /* regs */ \
.short 1; /* off 1 */ \
.long 0; /* imm */ \
if r0 < 10 goto l0_%=; \
r0 = 0; \
exit; \
" :: __imm(bpf_jiffies64)
: __clobber_all);
}
#if (defined(__TARGET_ARCH_arm64) || defined(__TARGET_ARCH_x86) || \
(defined(__TARGET_ARCH_riscv) && __riscv_xlen == 64) || \
defined(__TARGET_ARCH_arm) || defined(__TARGET_ARCH_s390) || \
defined(__TARGET_ARCH_loongarch)) && \
__clang_major__ >= 18
SEC("socket")
__success __retval(0)
__naked void gotol_and_may_goto(void)
{
asm volatile (" \
l0_%=: r0 = 0; \
.byte 0xe5; /* may_goto */ \
.byte 0; /* regs */ \
.short 1; /* off 1 */ \
.long 0; /* imm */ \
gotol l0_%=; \
r0 = 0; \
exit; \
" ::: __clobber_common);
}
#endif
SEC("socket")
__success __retval(0)
__naked void ja_and_may_goto_subprog(void)
{
asm volatile (" \
call subprog_with_may_goto; \
exit; \
" ::: __clobber_all);
}
static __naked __noinline __used
void subprog_with_may_goto(void)
{
asm volatile (" \
l0_%=: .byte 0xe5; /* may_goto */ \
.byte 0; /* regs */ \
.short 1; /* off 1 */ \
.long 0; /* imm */ \
goto l0_%=; \
r0 = 0; \
exit; \
" ::: __clobber_all);
}
#define ARR_SZ 1000000
int zero;
char arr[ARR_SZ];