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|
// SPDX-License-Identifier: GPL-2.0
/* Converted from tools/testing/selftests/bpf/verifier/ld_ind.c */
#include <linux/bpf.h>
#include <bpf/bpf_helpers.h>
#include "../../../include/linux/filter.h"
#include "bpf_misc.h"
SEC("socket")
__description("ld_ind: check calling conv, r1")
__failure __msg("R1 !read_ok")
__failure_unpriv
__naked void ind_check_calling_conv_r1(void)
{
asm volatile (" \
r6 = r1; \
r1 = 1; \
.8byte %[ld_ind]; \
r0 = r1; \
exit; \
" :
: __imm_insn(ld_ind, BPF_LD_IND(BPF_W, BPF_REG_1, -0x200000))
: __clobber_all);
}
SEC("socket")
__description("ld_ind: check calling conv, r2")
__failure __msg("R2 !read_ok")
__failure_unpriv
__naked void ind_check_calling_conv_r2(void)
{
asm volatile (" \
r6 = r1; \
r2 = 1; \
.8byte %[ld_ind]; \
r0 = r2; \
exit; \
" :
: __imm_insn(ld_ind, BPF_LD_IND(BPF_W, BPF_REG_2, -0x200000))
: __clobber_all);
}
SEC("socket")
__description("ld_ind: check calling conv, r3")
__failure __msg("R3 !read_ok")
__failure_unpriv
__naked void ind_check_calling_conv_r3(void)
{
asm volatile (" \
r6 = r1; \
r3 = 1; \
.8byte %[ld_ind]; \
r0 = r3; \
exit; \
" :
: __imm_insn(ld_ind, BPF_LD_IND(BPF_W, BPF_REG_3, -0x200000))
: __clobber_all);
}
SEC("socket")
__description("ld_ind: check calling conv, r4")
__failure __msg("R4 !read_ok")
__failure_unpriv
__naked void ind_check_calling_conv_r4(void)
{
asm volatile (" \
r6 = r1; \
r4 = 1; \
.8byte %[ld_ind]; \
r0 = r4; \
exit; \
" :
: __imm_insn(ld_ind, BPF_LD_IND(BPF_W, BPF_REG_4, -0x200000))
: __clobber_all);
}
SEC("socket")
__description("ld_ind: check calling conv, r5")
__failure __msg("R5 !read_ok")
__failure_unpriv
__naked void ind_check_calling_conv_r5(void)
{
asm volatile (" \
r6 = r1; \
r5 = 1; \
.8byte %[ld_ind]; \
r0 = r5; \
exit; \
" :
: __imm_insn(ld_ind, BPF_LD_IND(BPF_W, BPF_REG_5, -0x200000))
: __clobber_all);
}
SEC("socket")
__description("ld_ind: check calling conv, r7")
__success __success_unpriv __retval(1)
__naked void ind_check_calling_conv_r7(void)
{
asm volatile (" \
r6 = r1; \
r7 = 1; \
.8byte %[ld_ind]; \
r0 = r7; \
exit; \
" :
: __imm_insn(ld_ind, BPF_LD_IND(BPF_W, BPF_REG_7, -0x200000))
: __clobber_all);
}
/*
* ld_{abs,ind} subprog that always sets r0=1 on the success path.
* bpf_gen_ld_abs() emits a hidden exit with r0=0 when the load helper
* fails. The verifier must model this failure return so that callers
* account for r0=0 as a possible return value.
*/
__naked __noinline __used
static int ldabs_subprog(void)
{
asm volatile (
"r6 = r1;"
".8byte %[ld_abs];"
"r0 = 1;"
"exit;"
:
: __imm_insn(ld_abs, BPF_LD_ABS(BPF_W, 0))
: __clobber_all);
}
__naked __noinline __used
static int ldind_subprog(void)
{
asm volatile (
"r6 = r1;"
"r7 = 0;"
".8byte %[ld_ind];"
"r0 = 1;"
"exit;"
:
: __imm_insn(ld_ind, BPF_LD_IND(BPF_W, BPF_REG_7, 0))
: __clobber_all);
}
SEC("socket")
__description("ld_abs: subprog early exit on ld_abs failure")
__failure __msg("R9 !read_ok")
__naked void ld_abs_subprog_early_exit(void)
{
asm volatile (
"call ldabs_subprog;"
"if r0 != 0 goto l_exit_%=;"
"r0 = r9;"
"l_exit_%=:"
"r0 = 0;"
"exit;"
::: __clobber_all);
}
SEC("socket")
__description("ld_ind: subprog early exit on ld_ind failure")
__failure __msg("R9 !read_ok")
__naked void ld_ind_subprog_early_exit(void)
{
asm volatile (
"call ldind_subprog;"
"if r0 != 0 goto l_exit_%=;"
"r0 = r9;"
"l_exit_%=:"
"r0 = 0;"
"exit;"
::: __clobber_all);
}
SEC("socket")
__description("ld_abs: subprog with both paths safe")
__success
__naked void ld_abs_subprog_both_paths_safe(void)
{
asm volatile (
"call ldabs_subprog;"
"r0 = 0;"
"exit;"
::: __clobber_all);
}
SEC("socket")
__description("ld_ind: subprog with both paths safe")
__success
__naked void ld_ind_subprog_both_paths_safe(void)
{
asm volatile (
"call ldind_subprog;"
"r0 = 0;"
"exit;"
::: __clobber_all);
}
__naked __noinline __used
static int ld_abs_callback(void)
{
asm volatile (
"r6 = *(u64 *)(r2 + 0);"
".8byte %[ld_abs];"
"r0 = 0;"
"exit;"
:
: __imm_insn(ld_abs, BPF_LD_ABS(BPF_W, 0))
: __clobber_all);
}
SEC("socket")
__description("ld_abs: reject in callback")
__failure __msg("cannot use BPF_LD_[ABS|IND] within callback")
int ld_abs_callback_reject(struct __sk_buff *skb)
{
bpf_loop(1, ld_abs_callback, &skb, 0);
return 0;
}
__naked __noinline __used
static int ld_ind_callback_subprog(void)
{
asm volatile (
"r6 = r1;"
"r7 = 0;"
".8byte %[ld_ind];"
"r0 = 0;"
"exit;"
:
: __imm_insn(ld_ind, BPF_LD_IND(BPF_W, BPF_REG_7, 0))
: __clobber_all);
}
__naked __noinline __used
static int ld_ind_callback(void)
{
asm volatile (
"r1 = *(u64 *)(r2 + 0);"
"call ld_ind_callback_subprog;"
"exit;"
::: __clobber_all);
}
SEC("socket")
__description("ld_ind: reject in callback subprog")
__failure __msg("cannot use BPF_LD_[ABS|IND] within callback")
int ld_ind_callback_subprog_reject(struct __sk_buff *skb)
{
bpf_loop(1, ld_ind_callback, &skb, 0);
return 0;
}
static __noinline int ld_ind_global_static(struct __sk_buff *skb)
{
asm volatile (
"r6 = %[skb];"
"r7 = 0;"
".8byte %[ld_ind];"
:
: [skb] "r"(skb),
__imm_insn(ld_ind, BPF_LD_IND(BPF_W, BPF_REG_7, 0))
: __clobber_common, "r6", "r7");
return skb->mark;
}
__noinline int ld_ind_global(struct __sk_buff *skb)
{
return ld_ind_global_static(skb);
}
static int ld_ind_global_callback(__u32 index, struct __sk_buff **ctx)
{
ld_ind_global(*ctx);
return 0;
}
SEC("socket")
__description("ld_ind: reject in callback global subprog")
__failure __msg("cannot use BPF_LD_[ABS|IND] within callback")
int ld_ind_global_callback_reject(struct __sk_buff *skb)
{
bpf_loop(1, ld_ind_global_callback, &skb, 0);
return 0;
}
SEC("socket")
__description("ld_ind: allow in non-callback global subprog")
__success
int ld_ind_global_subprog_ok(struct __sk_buff *skb)
{
return ld_ind_global(skb);
}
/*
* ld_{abs,ind} in subprogs require scalar (int) return type in BTF.
* A test with void return must be rejected.
*/
__naked __noinline __used
static void ldabs_void_subprog(void)
{
asm volatile (
"r6 = r1;"
".8byte %[ld_abs];"
"r0 = 1;"
"exit;"
:
: __imm_insn(ld_abs, BPF_LD_ABS(BPF_W, 0))
: __clobber_all);
}
SEC("socket")
__description("ld_abs: reject void return subprog")
__failure __msg("LD_ABS is only allowed in functions that return 'int'")
__naked void ld_abs_void_subprog_reject(void)
{
asm volatile (
"call ldabs_void_subprog;"
"r0 = 0;"
"exit;"
::: __clobber_all);
}
__naked __noinline __used
static void ldind_void_subprog(void)
{
asm volatile (
"r6 = r1;"
"r7 = 0;"
".8byte %[ld_ind];"
"r0 = 1;"
"exit;"
:
: __imm_insn(ld_ind, BPF_LD_IND(BPF_W, BPF_REG_7, 0))
: __clobber_all);
}
SEC("socket")
__description("ld_ind: reject void return subprog")
__failure __msg("LD_ABS is only allowed in functions that return 'int'")
__naked void ld_ind_void_subprog_reject(void)
{
asm volatile (
"call ldind_void_subprog;"
"r0 = 0;"
"exit;"
::: __clobber_all);
}
char _license[] SEC("license") = "GPL";
|
