// SPDX-License-Identifier: GPL-2.0
/* Converted from tools/testing/selftests/bpf/verifier/ref_tracking.c */
#include <linux/bpf.h>
#include <bpf/bpf_helpers.h>
#include "../../../include/linux/filter.h"
#include "bpf_misc.h"
#define BPF_SK_LOOKUP(func) \
/* struct bpf_sock_tuple tuple = {} */ \
"r2 = 0;" \
"*(u32*)(r10 - 8) = r2;" \
"*(u64*)(r10 - 16) = r2;" \
"*(u64*)(r10 - 24) = r2;" \
"*(u64*)(r10 - 32) = r2;" \
"*(u64*)(r10 - 40) = r2;" \
"*(u64*)(r10 - 48) = r2;" \
/* sk = func(ctx, &tuple, sizeof tuple, 0, 0) */ \
"r2 = r10;" \
"r2 += -48;" \
"r3 = %[sizeof_bpf_sock_tuple];"\
"r4 = 0;" \
"r5 = 0;" \
"call %[" #func "];"
struct bpf_key {} __attribute__((preserve_access_index));
extern void bpf_key_put(struct bpf_key *key) __ksym;
extern struct bpf_key *bpf_lookup_system_key(__u64 id) __ksym;
extern struct bpf_key *bpf_lookup_user_key(__u32 serial, __u64 flags) __ksym;
/* BTF FUNC records are not generated for kfuncs referenced
* from inline assembly. These records are necessary for
* libbpf to link the program. The function below is a hack
* to ensure that BTF FUNC records are generated.
*/
void __kfunc_btf_root(void)
{
bpf_key_put(0);
bpf_lookup_system_key(0);
bpf_lookup_user_key(0, 0);
}
#define MAX_ENTRIES 11
struct test_val {
unsigned int index;
int foo[MAX_ENTRIES];
};
struct {
__uint(type, BPF_MAP_TYPE_ARRAY);
__uint(max_entries, 1);
__type(key, int);
__type(value, struct test_val);
} map_array_48b SEC(".maps");
struct {
__uint(type, BPF_MAP_TYPE_RINGBUF);
__uint(max_entries, 4096);
} map_ringbuf SEC(".maps");
void dummy_prog_42_tc(void);
void dummy_prog_24_tc(void);
void dummy_prog_loop1_tc(void);
struct {
__uint(type, BPF_MAP_TYPE_PROG_ARRAY);
__uint(max_entries, 4);
__uint(key_size, sizeof(int));
__array(values, void (void));
} map_prog1_tc SEC(".maps") = {
.values = {
[0] = (void *)&dummy_prog_42_tc,
[1] = (void *)&dummy_prog_loop1_tc,
[2] = (void *)&dummy_prog_24_tc,
},
};
SEC("tc")
__auxiliary
__naked void dummy_prog_42_tc(void)
{
asm volatile ("r0 = 42; exit;");
}
SEC("tc")
__auxiliary
__naked void dummy_prog_24_tc(void)
{
asm volatile ("r0 = 24; exit;");
}
SEC("tc")
__auxiliary
__naked void dummy_prog_loop1_tc(void)
{
asm volatile (" \
r3 = 1; \
r2 = %[map_prog1_tc] ll; \
call %[bpf_tail_call]; \
r0 = 41; \
exit; \
" :
: __imm(bpf_tail_call),
__imm_addr(map_prog1_tc)
: __clobber_all);
}
SEC("tc")
__description("reference tracking: leak potential reference")
__failure __msg("Unreleased reference")
__naked void reference_tracking_leak_potential_reference(void)
{
asm volatile (
BPF_SK_LOOKUP(bpf_sk_lookup_tcp)
" r6 = r0; /* leak reference */ \
exit; \
" :
: __imm(bpf_sk_lookup_tcp),
__imm_const(sizeof_bpf_sock_tuple, sizeof(struct bpf_sock_tuple))
: __clobber_all);
}
SEC("tc")
__description("reference tracking: leak potential reference to sock_common")
__failure __msg("Unreleased reference")
__naked void potential_reference_to_sock_common_1(void)
{
asm volatile (
BPF_SK_LOOKUP(bpf_skc_lookup_tcp)
" r6 = r0; /* leak reference */ \
exit; \
" :
: __imm(bpf_skc_lookup_tcp),
__imm_const(sizeof_bpf_sock_tuple, sizeof(struct bpf_sock_tuple))
: __clobber_all);
}
SEC("tc")
__description("reference tracking: leak potential reference on stack")
__failure __msg("Unreleased reference")
__naked void leak_potential_reference_on_stack(void)
{
asm volatile (
BPF_SK_LOOKUP(bpf_sk_lookup_tcp)
" r4 = r10; \
r4 += -8; \
*(u64*)(r4 + 0) = r0; \
r0 = 0; \
exit; \
" :
: __imm(bpf_sk_lookup_tcp),
__imm_const(sizeof_bpf_sock_tuple, sizeof(struct bpf_sock_tuple))
: __clobber_all);
}
SEC("tc")
__description("reference tracking: leak potential reference on stack 2")
__failure __msg("Unreleased reference")
__naked void potential_reference_on_stack_2(void)
{
asm volatile (
BPF_SK_LOOKUP(bpf_sk_lookup_tcp)
" r4 = r10; \
r4 += -8; \
*(u64*)(r4 + 0) = r0; \
r0 = 0; \
r1 = 0; \
*(u64*)(r4 + 0) = r1; \
exit; \
" :
: __imm(bpf_sk_lookup_tcp),
__imm_const(sizeof_bpf_sock_tuple, sizeof(struct bpf_sock_tuple))
: __clobber_all);
}
SEC("tc")
__description("reference tracking: zero potential reference")
__failure __msg("Unreleased reference")
__naked void reference_tracking_zero_potential_reference(void)
{
asm volatile (
BPF_SK_LOOKUP(bpf_sk_lookup_tcp)
" r0 = 0; /* leak reference */ \
exit; \
" :
: __imm(bpf_sk_lookup_tcp),
__imm_const(sizeof_bpf_sock_tuple, sizeof(struct bpf_sock_tuple))
: __clobber_all);
}
SEC("tc")
__description("reference tracking: zero potential reference to sock_common")
__failure __msg("Unreleased reference")
__naked void potential_reference_to_sock_common_2(void)
{
asm volatile (
BPF_SK_LOOKUP(bpf_skc_lookup_tcp)
" r0 = 0; /* leak reference */ \
exit; \
" :
: __imm(bpf_skc_lookup_tcp),
__imm_const(sizeof_bpf_sock_tuple, sizeof(struct bpf_sock_tuple))
: __clobber_all);
}
SEC("tc")
__description("reference tracking: copy and zero potential references")
__failure __msg("Unreleased reference")
__naked void copy_and_zero_potential_references(void)
{
asm volatile (
BPF_SK_LOOKUP(bpf_sk_lookup_tcp)
" r7 = r0; \
r0 = 0; \
r7 = 0; /* leak reference */ \
exit; \
" :
: __imm(bpf_sk_lookup_tcp),
__imm_const(sizeof_bpf_sock_tuple, sizeof(struct bpf_sock_tuple))
: __clobber_all);
}
SEC("lsm.s/bpf")
__description("reference tracking: acquire/release user key reference")
__success
__naked void acquire_release_user_key_reference(void)
{
asm volatile (" \
r1 = -3; \
r2 = 0; \
call %[bpf_lookup_user_key]; \
if r0 == 0 goto l0_%=; \
r1 = r0; \
call %[bpf_key_put]; \
l0_%=: r0 = 0; \
exit; \
" :
: __imm(bpf_key_put),
__imm(bpf_lookup_user_key)
: __clobber_all);
}
SEC("lsm.s/bpf")
__description("reference tracking: acquire/release system key reference")
__success
__naked void acquire_release_system_key_reference(void)
{
asm volatile (" \
r1 = 1; \
call %[bpf_lookup_system_key]; \
if r0 == 0 goto l0_%=; \
r1 = r0; \
call %[bpf_key_put]; \
l0_%=: r0 = 0; \
exit; \
" :
: __imm(bpf_key_put),
__imm(bpf_lookup_system_key)
: __clobber_all);
}
SEC("lsm.s/bpf")
__description("reference tracking: release user key reference without check")
__failure __msg("Possibly NULL pointer passed to trusted arg0")
__naked void user_key_reference_without_check(void)
{
asm volatile (" \
r1 = -3; \
r2 = 0; \
call %[bpf_lookup_user_key]; \
r1 = r0; \
call %[bpf_key_put]; \
r0 = 0; \
exit; \
" :
: __imm(bpf_key_put),
__imm(bpf_lookup_user_key)
: __clobber_all);
}
SEC("lsm.s/bpf")
__description("reference tracking: release system key reference without check")
__failure __msg("Possibly NULL pointer passed to trusted arg0")
__naked void system_key_reference_without_check(void)
{
asm volatile (" \
r1 = 1; \
call %[bpf_lookup_system_key]; \
r1 = r0; \
call %[bpf_key_put]; \
r0 = 0; \
exit; \
" :
: __imm(bpf_key_put),
__imm(bpf_lookup_system_key)
: __clobber_all);
}
SEC("lsm.s/bpf")
__description("reference tracking: release with NULL key pointer")
__failure __msg("Possibly NULL pointer passed to trusted arg0")
__naked void release_with_null_key_pointer(void)
{
asm volatile (" \
r1 = 0; \
call %[bpf_key_put]; \
r0 = 0; \
exit; \
" :
: __imm(bpf_key_put)
: __clobber_all);
}
SEC("lsm.s/bpf")
__description("reference tracking: leak potential reference to user key")
__failure __msg("Unreleased reference")
__naked void potential_reference_to_user_key(void)
{
asm volatile (" \
r1 = -3; \
r2 = 0; \
call %[bpf_lookup_user_key]; \
exit; \
" :
: __imm(bpf_lookup_user_key)
: __clobber_all);
}
SEC("lsm.s/bpf")
__description("reference tracking: leak potential reference to system key")
__failure __msg("Unreleased reference")
__naked void potential_reference_to_system_key(void)
{
asm volatile (" \
r1 = 1; \
call %[bpf_lookup_system_key]; \
exit; \
" :
: __imm(bpf_lookup_system_key)
: __clobber_all);
}
SEC("tc")
__description("reference tracking: release reference without check")
__failure __msg("type=sock_or_null expected=sock")
__naked void tracking_release_reference_without_check(void)
{
asm volatile (
BPF_SK_LOOKUP(bpf_sk_lookup_tcp)
" /* reference in r0 may be NULL */ \
r1 = r0; \
r2 = 0; \
call %[bpf_sk_release]; \
exit; \
" :
: __imm(bpf_sk_lookup_tcp),
__imm(bpf_sk_release),
__imm_const(sizeof_bpf_sock_tuple, sizeof(struct bpf_sock_tuple))
: __clobber_all);
}
SEC("tc")
__description("reference tracking: release reference to sock_common without check")
__failure __msg("type=sock_common_or_null expected=sock")
__naked void to_sock_common_without_check(void)
{
asm volatile (
BPF_SK_LOOKUP(bpf_skc_lookup_tcp)
" /* reference in r0 may be NULL */ \
r1 = r0; \
r2 = 0; \
call %[bpf_sk_release]; \
exit; \
" :
: __imm(bpf_sk_release),
__imm(bpf_skc_lookup_tcp),
__imm_const(sizeof_bpf_sock_tuple, sizeof(struct bpf_sock_tuple))
: __clobber_all);
}
SEC("tc")
__description("reference tracking: release reference")
__success __retval(0)
__naked void reference_tracking_release_reference(void)
{
asm volatile (
BPF_SK_LOOKUP(bpf_sk_lookup_tcp)
" r1 = r0; \
if r0 == 0 goto l0_%=; \
call %[bpf_sk_release]; \
l0_%=: exit; \
" :
: __imm(bpf_sk_lookup_tcp),
__imm(bpf_sk_release),
__imm_const(sizeof_bpf_sock_tuple, sizeof(struct bpf_sock_tuple))
: __clobber_all);
}
SEC("tc")
__description("reference tracking: release reference to sock_common")
__success __retval(0)
__naked void release_reference_to_sock_common(void)
{
asm volatile (
BPF_SK_LOOKUP(bpf_skc_lookup_tcp)
" r1 = r0; \
if r0 == 0 goto l0_%=; \
call %[bpf_sk_release]; \
l0_%=: exit; \
" :
: __imm(bpf_sk_release),
__imm(bpf_skc_lookup_tcp),
__imm_const(sizeof_bpf_sock_tuple, sizeof(struct bpf_sock_tuple))
: __clobber_all);
}
SEC("tc")
__description("reference tracking: release reference 2")
__success __retval(0)
__naked void reference_tracking_release_reference_2(void)
{
asm volatile (
BPF_SK_LOOKUP(bpf_sk_lookup_tcp)
" r1 = r0; \
if r0 != 0 goto l0_%=; \
exit; \
l0_%=: call %[bpf_sk_release]; \
exit; \
" :
: __imm(bpf_sk_lookup_tcp),
__imm(bpf_sk_release),
__imm_const(sizeof_bpf_sock_tuple, sizeof(struct bpf_sock_tuple))
: __clobber_all);
}
SEC("tc")
__description("reference tracking: release reference twice")
__failure __msg("type=scalar expected=sock")
__naked void reference_tracking_release_reference_twice(void)
{
asm volatile (
BPF_SK_LOOKUP(bpf_sk_lookup_tcp)
" r1 = r0; \
r6 = r0; \
if r0 == 0 goto l0_%=; \
call %[bpf_sk_release]; \
l0_%=: r1 = r6; \
call %[bpf_sk_release]; \
exit; \
" :
: __imm(bpf_sk_lookup_tcp),
__imm(bpf_sk_release),
__imm_const(sizeof_bpf_sock_tuple, sizeof(struct bpf_sock_tuple))
: __clobber_all);
}
SEC("tc")
__description("reference tracking: release reference twice inside branch")
__failure __msg("type=scalar expected=sock")
__naked void release_reference_twice_inside_branch(void)
{
asm volatile (
BPF_SK_LOOKUP(bpf_sk_lookup_tcp)
" r1 = r0; \
r6 = r0; \
if r0 == 0 goto l0_%=; /* goto end */ \
call %[bpf_sk_release]; \
r1 = r6; \
call %[bpf_sk_release]; \
l0_%=: exit; \
" :
: __imm(bpf_sk_lookup_tcp),
__imm(bpf_sk_release),
__imm_const(sizeof_bpf_sock_tuple, sizeof(struct bpf_sock_tuple))
: __clobber_all);
}
SEC("tc")
__description("reference tracking: alloc, check, free in one subbranch")
__failure __msg("Unreleased reference")
__flag(BPF_F_ANY_ALIGNMENT)
__naked void check_free_in_one_subbranch(void)
{
asm volatile (" \
r2 = *(u32*)(r1 + %[__sk_buff_data]); \
r3 = *(u32*)(r1 + %[__sk_buff_data_end]); \
r0 = r2; \
r0 += 16; \
/* if (offsetof(skb, mark) > data_len) exit; */ \
if r0 <= r3 goto l0_%=; \
exit; \
l0_%=: r6 = *(u32*)(r2 + %[__sk_buff_mark]); \
" BPF_SK_LOOKUP(bpf_sk_lookup_tcp)
" if r6 == 0 goto l1_%=; /* mark == 0? */\
/* Leak reference in R0 */ \
exit; \
l1_%=: if r0 == 0 goto l2_%=; /* sk NULL? */ \
r1 = r0; \
call %[bpf_sk_release]; \
l2_%=: exit; \
" :
: __imm(bpf_sk_lookup_tcp),
__imm(bpf_sk_release),
__imm_const(__sk_buff_data, offsetof(struct __sk_buff, data)),
__imm_const(__sk_buff_data_end, offsetof(struct __sk_buff, data_end)),
__imm_const(__sk_buff_mark, offsetof(struct __sk_buff, mark)),
__imm_const(sizeof_bpf_sock_tuple, sizeof(struct bpf_sock_tuple))
: __clobber_all);
}
SEC("tc")
__description("reference tracking: alloc, check, free in both subbranches")
__success __retval(0) __flag(BPF_F_ANY_ALIGNMENT)
__naked void check_free_in_both_subbranches(void)
{
asm volatile (" \
r2 = *(u32*)(r1 + %[__sk_buff_data]); \
r3 = *(u32*)(r1 + %[__sk_buff_data_end]); \
r0 = r2; \
r0 += 16; \
/* if (offsetof(skb, mark) > data_len) exit; */ \
if r0 <= r3 goto l0_%=; \
exit; \
l0_%=: r6 = *(u32*)(r2 + %[__sk_buff_mark]); \
" BPF_SK_LOOKUP(bpf_sk_lookup_tcp)
" if r6 == 0 goto l1_%=; /* mark == 0? */\
if r0 == 0 goto l2_%=; /* sk NULL? */ \
r1 = r0; \
call %[bpf_sk_release]; \
l2_%=: exit; \
l1_%=: if r0 == 0 goto l3_%=; /* sk NULL? */ \
r1 = r0; \
call %[bpf_sk_release]; \
l3_%=: exit; \
" :
: __imm(bpf_sk_lookup_tcp),
__imm(bpf_sk_release),
__imm_const(__sk_buff_data, offsetof(struct __sk_buff, data)),
__imm_const(__sk_buff_data_end, offsetof(struct __sk_buff, data_end)),
__imm_const(__sk_buff_mark, offsetof(struct __sk_buff, mark)),
__imm_const(sizeof_bpf_sock_tuple, sizeof(struct bpf_sock_tuple))
: __clobber_all);
}
SEC("tc")
__description("reference tracking in call: free reference in subprog")
__success __retval(0)
__naked void call_free_reference_in_subprog(void)
{
asm volatile (
BPF_SK_LOOKUP(bpf_sk_lookup_tcp)
" r1 = r0; /* unchecked reference */ \
call call_free_reference_in_subprog__1; \
r0 = 0; \
exit; \
" :
: __imm(bpf_sk_lookup_tcp),
__imm_const(sizeof_bpf_sock_tuple, sizeof(struct bpf_sock_tuple))
: __clobber_all);
}
static __naked __noinline __attribute__((used))
void call_free_reference_in_subprog__1(void)
{
asm volatile (" \
/* subprog 1 */ \
r2 = r1; \
if r2 == 0 goto l0_%=; \
call %[bpf_sk_release]; \
l0_%=: exit; \
" :
: __imm(bpf_sk_release)
: __clobber_all);
}
SEC("tc")
__description("reference tracking in call: free reference in subprog and outside")
__failure __msg("type=scalar expected=sock")
__naked void reference_in_subprog_and_outside(void)
{
asm volatile (
BPF_SK_LOOKUP(bpf_sk_lookup_tcp)
" r1 = r0; /* unchecked reference */ \
r6 = r0; \
call reference_in_subprog_and_outside__1; \
r1 = r6; \
call %[bpf_sk_release]; \
exit; \
" :
: __imm(bpf_sk_lookup_tcp),
__imm(bpf_sk_release),
__imm_const(sizeof_bpf_sock_tuple, sizeof(struct bpf_sock_tuple))
: __clobber_all);
}
static __naked __noinline __attribute__((used))
void reference_in_subprog_and_outside__1(void)
{
asm volatile (" \
/* subprog 1 */ \
r2 = r1; \
if r2 == 0 goto l0_%=; \
call %[bpf_sk_release]; \
l0_%=: exit; \
" :
: __imm(bpf_sk_release)
: __clobber_all);
}
SEC("tc")
__description("reference tracking in call: alloc & leak reference in subprog")
__failure __msg("Unreleased reference")
__naked void alloc_leak_reference_in_subprog(void)
{
asm volatile (" \
r4 = r10; \
r4 += -8; \
call alloc_leak_reference_in_subprog__1; \
r1 = r0; \
r0 = 0; \
exit; \
" ::: __clobber_all);
}
static __naked __noinline __attribute__((used))
void alloc_leak_reference_in_subprog__1(void)
{
asm volatile (" \
/* subprog 1 */ \
r6 = r4; \
" BPF_SK_LOOKUP(bpf_sk_lookup_tcp)
" /* spill unchecked sk_ptr into stack of caller */\
*(u64*)(r6 + 0) = r0; \
r1 = r0; \
exit; \
" :
: __imm(bpf_sk_lookup_tcp),
__imm_const(sizeof_bpf_sock_tuple, sizeof(struct bpf_sock_tuple))
: __clobber_all);
}
SEC("tc")
__description("reference tracking in call: alloc in subprog, release outside")
__success __retval(POINTER_VALUE)
__naked void alloc_in_subprog_release_outside(void)
{
asm volatile (" \
r4 = r10; \
call alloc_in_subprog_release_outside__1; \
r1 = r0; \
if r0 == 0 goto l0_%=; \
call %[bpf_sk_release]; \
l0_%=: exit; \
" :
: __imm(bpf_sk_release)
: __clobber_all);
}
static __naked __noinline __attribute__((used))
void alloc_in_subprog_release_outside__1(void)
{
asm volatile (" \
/* subprog 1 */ \
" BPF_SK_LOOKUP(bpf_sk_lookup_tcp)
" exit; /* return sk */ \
" :
: __imm(bpf_sk_lookup_tcp),
__imm_const(sizeof_bpf_sock_tuple, sizeof(struct bpf_sock_tuple))
: __clobber_all);
}
SEC("tc")
__description("reference tracking in call: sk_ptr leak into caller stack")
__failure __msg("Unreleased reference")
__naked void ptr_leak_into_caller_stack(void)
{
asm volatile (" \
r4 = r10; \
r4 += -8; \
call ptr_leak_into_caller_stack__1; \
r0 = 0; \
exit; \
" ::: __clobber_all);
}
static __naked __noinline __attribute__((used))
void ptr_leak_into_caller_stack__1(void)
{
asm volatile (" \
/* subprog 1 */ \
r5 = r10; \
r5 += -8; \
*(u64*)(r5 + 0) = r4; \
call ptr_leak_into_caller_stack__2; \
/* spill unchecked sk_ptr into stack of caller */\
r5 = r10; \
r5 += -8; \
r4 = *(u64*)(r5 + 0); \
*(u64*)(r4 + 0) = r0; \
exit; \
" ::: __clobber_all);
}
static __naked __noinline __attribute__((used))
void ptr_leak_into_caller_stack__2(void)
{
asm volatile (" \
/* subprog 2 */ \
" BPF_SK_LOOKUP(bpf_sk_lookup_tcp)
" exit; \
" :
: __imm(bpf_sk_lookup_tcp),
__imm_const(sizeof_bpf_sock_tuple, sizeof(struct bpf_sock_tuple))
: __clobber_all);
}
SEC("tc")
__description("reference tracking in call: sk_ptr spill into caller stack")
__success __retval(0)
__naked void ptr_spill_into_caller_stack(void)
{
asm volatile (" \
r4 = r10; \
r4 += -8; \
call ptr_spill_into_caller_stack__1; \
r0 = 0; \
exit; \
" ::: __clobber_all);
}
static __naked __noinline __attribute__((used))
void ptr_spill_into_caller_stack__1(void)
{
asm volatile (" \
/* subprog 1 */ \
r5 = r10; \
r5 += -8; \
*(u64*)(r5 + 0) = r4; \
call ptr_spill_into_caller_stack__2; \
/* spill unchecked sk_ptr into stack of caller */\
r5 = r10; \
r5 += -8; \
r4 = *(u64*)(r5 + 0); \
*(u64*)(r4 + 0) = r0; \
if r0 == 0 goto l0_%=; \
/* now the sk_ptr is verified, free the reference */\
r1 = *(u64*)(r4 + 0); \
call %[bpf_sk_release]; \
l0_%=: exit; \
" :
: __imm(bpf_sk_release)
: __clobber_all);
}
static __naked __noinline __attribute__((used))
void ptr_spill_into_caller_stack__2(void)
{
asm volatile (" \
/* subprog 2 */ \
" BPF_SK_LOOKUP(bpf_sk_lookup_tcp)
" exit; \
" :
: __imm(bpf_sk_lookup_tcp),
__imm_const(sizeof_bpf_sock_tuple, sizeof(struct bpf_sock_tuple))
: __clobber_all);
}
SEC("tc")
__description("reference tracking: allow LD_ABS")
__success __retval(0)
__naked void reference_tracking_allow_ld_abs(void)
{
asm volatile (" \
r6 = r1; \
" BPF_SK_LOOKUP(bpf_sk_lookup_tcp)
" r1 = r0; \
if r0 == 0 goto l0_%=; \
call %[bpf_sk_release]; \
l0_%=: r0 = *(u8*)skb[0]; \
r0 = *(u16*)skb[0]; \
r0 = *(u32*)skb[0]; \
exit; \
" :
: __imm(bpf_sk_lookup_tcp),
__imm(bpf_sk_release),
__imm_const(sizeof_bpf_sock_tuple, sizeof(struct bpf_sock_tuple))
: __clobber_all);
}
SEC("tc")
__description("reference tracking: forbid LD_ABS while holding reference")
__failure __msg("BPF_LD_[ABS|IND] cannot be mixed with socket references")
__naked void ld_abs_while_holding_reference(void)
{
asm volatile (" \
r6 = r1; \
" BPF_SK_LOOKUP(bpf_sk_lookup_tcp)
" r0 = *(u8*)skb[0]; \
r0 = *(u16*)skb[0]; \
r0 = *(u32*)skb[0]; \
r1 = r0; \
if r0 == 0 goto l0_%=; \
call %[bpf_sk_release]; \
l0_%=: exit; \
" :
: __imm(bpf_sk_lookup_tcp),
__imm(bpf_sk_release),
__imm_const(sizeof_bpf_sock_tuple, sizeof(struct bpf_sock_tuple))
: __clobber_all);
}
SEC("tc")
__description("reference tracking: allow LD_IND")
__success __retval(1)
__naked void reference_tracking_allow_ld_ind(void)
{
asm volatile (" \
r6 = r1; \
" BPF_SK_LOOKUP(bpf_sk_lookup_tcp)
" r1 = r0; \
if r0 == 0 goto l0_%=; \
call %[bpf_sk_release]; \
l0_%=: r7 = 1; \
.8byte %[ld_ind]; \
r0 = r7; \
exit; \
" :
: __imm(bpf_sk_lookup_tcp),
__imm(bpf_sk_release),
__imm_const(sizeof_bpf_sock_tuple, sizeof(struct bpf_sock_tuple)),
__imm_insn(ld_ind, BPF_LD_IND(BPF_W, BPF_REG_7, -0x200000))
: __clobber_all);
}
SEC("tc")
__description("reference tracking: forbid LD_IND while holding reference")
__failure __msg("BPF_LD_[ABS|IND] cannot be mixed with socket references")
__naked void ld_ind_while_holding_reference(void)
{
asm volatile (" \
r6 = r1; \
" BPF_SK_LOOKUP(bpf_sk_lookup_tcp)
" r4 = r0; \
r7 = 1; \
.8byte %[ld_ind]; \
r0 = r7; \
r1 = r4; \
if r1 == 0 goto l0_%=; \
call %[bpf_sk_release]; \
l0_%=: exit; \
" :
: __imm(bpf_sk_lookup_tcp),
__imm(bpf_sk_release),
__imm_const(sizeof_bpf_sock_tuple, sizeof(struct bpf_sock_tuple)),
__imm_insn(ld_ind, BPF_LD_IND(BPF_W, BPF_REG_7, -0x200000))
: __clobber_all);
}
SEC("tc")
__description("reference tracking: check reference or tail call")
__success __retval(0)
__naked void check_reference_or_tail_call(void)
{
asm volatile (" \
r7 = r1; \
" BPF_SK_LOOKUP(bpf_sk_lookup_tcp)
" /* if (sk) bpf_sk_release() */ \
r1 = r0; \
if r1 != 0 goto l0_%=; \
/* bpf_tail_call() */ \
r3 = 3; \
r2 = %[map_prog1_tc] ll; \
r1 = r7; \
call %[bpf_tail_call]; \
r0 = 0; \
exit; \
l0_%=: call %[bpf_sk_release]; \
exit; \
" :
: __imm(bpf_sk_lookup_tcp),
__imm(bpf_sk_release),
__imm(bpf_tail_call),
__imm_addr(map_prog1_tc),
__imm_const(sizeof_bpf_sock_tuple, sizeof(struct bpf_sock_tuple))
: __clobber_all);
}
SEC("tc")
__description("reference tracking: release reference then tail call")
__success __retval(0)
__naked void release_reference_then_tail_call(void)
{
asm volatile (" \
r7 = r1; \
" BPF_SK_LOOKUP(bpf_sk_lookup_tcp)
" /* if (sk) bpf_sk_release() */ \
r1 = r0; \
if r1 == 0 goto l0_%=; \
call %[bpf_sk_release]; \
l0_%=: /* bpf_tail_call() */ \
r3 = 3; \
r2 = %[map_prog1_tc] ll; \
r1 = r7; \
call %[bpf_tail_call]; \
r0 = 0; \
exit; \
" :
: __imm(bpf_sk_lookup_tcp),
__imm(bpf_sk_release),
__imm(bpf_tail_call),
__imm_addr(map_prog1_tc),
__imm_const(sizeof_bpf_sock_tuple, sizeof(struct bpf_sock_tuple))
: __clobber_all);
}
SEC("tc")
__description("reference tracking: leak possible reference over tail call")
__failure __msg("tail_call would lead to reference leak")
__naked void possible_reference_over_tail_call(void)
{
asm volatile (" \
r7 = r1; \
/* Look up socket and store in REG_6 */ \
" BPF_SK_LOOKUP(bpf_sk_lookup_tcp)
" /* bpf_tail_call() */ \
r6 = r0; \
r3 = 3; \
r2 = %[map_prog1_tc] ll; \
r1 = r7; \
call %[bpf_tail_call]; \
r0 = 0; \
/* if (sk) bpf_sk_release() */ \
r1 = r6; \
if r1 == 0 goto l0_%=; \
call %[bpf_sk_release]; \
l0_%=: exit; \
" :
: __imm(bpf_sk_lookup_tcp),
__imm(bpf_sk_release),
__imm(bpf_tail_call),
__imm_addr(map_prog1_tc),
__imm_const(sizeof_bpf_sock_tuple, sizeof(struct bpf_sock_tuple))
: __clobber_all);
}
SEC("tc")
__description("reference tracking: leak checked reference over tail call")
__failure __msg("tail_call would lead to reference leak")
__naked void checked_reference_over_tail_call(void)
{
asm volatile (" \
r7 = r1; \
/* Look up socket and store in REG_6 */ \
" BPF_SK_LOOKUP(bpf_sk_lookup_tcp)
" r6 = r0; \
/* if (!sk) goto end */ \
if r0 == 0 goto l0_%=; \
/* bpf_tail_call() */ \
r3 = 0; \
r2 = %[map_prog1_tc] ll; \
r1 = r7; \
call %[bpf_tail_call]; \
r0 = 0; \
r1 = r6; \
l0_%=: call %[bpf_sk_release]; \
exit; \
" :
: __imm(bpf_sk_lookup_tcp),
__imm(bpf_sk_release),
__imm(bpf_tail_call),
__imm_addr(map_prog1_tc),
__imm_const(sizeof_bpf_sock_tuple, sizeof(struct bpf_sock_tuple))
: __clobber_all);
}
SEC("tc")
__description("reference tracking: mangle and release sock_or_null")
__failure __msg("R1 pointer arithmetic on sock_or_null prohibited")
__naked void and_release_sock_or_null(void)
{
asm volatile (
BPF_SK_LOOKUP(bpf_sk_lookup_tcp)
" r1 = r0; \
r1 += 5; \
if r0 == 0 goto l0_%=; \
call %[bpf_sk_release]; \
l0_%=: exit; \
" :
: __imm(bpf_sk_lookup_tcp),
__imm(bpf_sk_release),
__imm_const(sizeof_bpf_sock_tuple, sizeof(struct bpf_sock_tuple))
: __clobber_all);
}
SEC("tc")
__description("reference tracking: mangle and release sock")
__failure __msg("R1 pointer arithmetic on sock prohibited")
__naked void tracking_mangle_and_release_sock(void)
{
asm volatile (
BPF_SK_LOOKUP(bpf_sk_lookup_tcp)
" r1 = r0; \
if r0 == 0 goto l0_%=; \
r1 += 5; \
call %[bpf_sk_release]; \
l0_%=: exit; \
" :
: __imm(bpf_sk_lookup_tcp),
__imm(bpf_sk_release),
__imm_const(sizeof_bpf_sock_tuple, sizeof(struct bpf_sock_tuple))
: __clobber_all);
}
SEC("tc")
__description("reference tracking: access member")
__success __retval(0)
__naked void reference_tracking_access_member(void)
{
asm volatile (
BPF_SK_LOOKUP(bpf_sk_lookup_tcp)
" r6 = r0; \
if r0 == 0 goto l0_%=; \
r2 = *(u32*)(r0 + 4); \
r1 = r6; \
call %[bpf_sk_release]; \
l0_%=: exit; \
" :
: __imm(bpf_sk_lookup_tcp),
__imm(bpf_sk_release),
__imm_const(sizeof_bpf_sock_tuple, sizeof(struct bpf_sock_tuple))
: __clobber_all);
}
SEC("tc")
__description("reference tracking: write to member")
__failure __msg("cannot write into sock")
__naked void reference_tracking_write_to_member(void)
{
asm volatile (
BPF_SK_LOOKUP(bpf_sk_lookup_tcp)
" r6 = r0; \
if r0 == 0 goto l0_%=; \
r1 = r6; \
r2 = 42 ll; \
*(u32*)(r1 + %[bpf_sock_mark]) = r2; \
r1 = r6; \
l0_%=: call %[bpf_sk_release]; \
r0 = 0 ll; \
exit; \
" :
: __imm(bpf_sk_lookup_tcp),
__imm(bpf_sk_release),
__imm_const(bpf_sock_mark, offsetof(struct bpf_sock, mark)),
__imm_const(sizeof_bpf_sock_tuple, sizeof(struct bpf_sock_tuple))
: __clobber_all);
}
SEC("tc")
__description("reference tracking: invalid 64-bit access of member")
__failure __msg("invalid sock access off=0 size=8")
__naked void _64_bit_access_of_member(void)
{
asm volatile (
BPF_SK_LOOKUP(bpf_sk_lookup_tcp)
" r6 = r0; \
if r0 == 0 goto l0_%=; \
r2 = *(u64*)(r0 + 0); \
r1 = r6; \
call %[bpf_sk_release]; \
l0_%=: exit; \
" :
: __imm(bpf_sk_lookup_tcp),
__imm(bpf_sk_release),
__imm_const(sizeof_bpf_sock_tuple, sizeof(struct bpf_sock_tuple))
: __clobber_all);
}
SEC("tc")
__description("reference tracking: access after release")
__failure __msg("!read_ok")
__naked void reference_tracking_access_after_release(void)
{
asm volatile (
BPF_SK_LOOKUP(bpf_sk_lookup_tcp)
" r1 = r0; \
if r0 == 0 goto l0_%=; \
call %[bpf_sk_release]; \
r2 = *(u32*)(r1 + 0); \
l0_%=: exit; \
" :
: __imm(bpf_sk_lookup_tcp),
__imm(bpf_sk_release),
__imm_const(sizeof_bpf_sock_tuple, sizeof(struct bpf_sock_tuple))
: __clobber_all);
}
SEC("tc")
__description("reference tracking: direct access for lookup")
__success __retval(0)
__naked void tracking_direct_access_for_lookup(void)
{
asm volatile (" \
/* Check that the packet is at least 64B long */\
r2 = *(u32*)(r1 + %[__sk_buff_data]); \
r3 = *(u32*)(r1 + %[__sk_buff_data_end]); \
r0 = r2; \
r0 += 64; \
if r0 > r3 goto l0_%=; \
/* sk = sk_lookup_tcp(ctx, skb->data, ...) */ \
r3 = %[sizeof_bpf_sock_tuple]; \
r4 = 0; \
r5 = 0; \
call %[bpf_sk_lookup_tcp]; \
r6 = r0; \
if r0 == 0 goto l0_%=; \
r2 = *(u32*)(r0 + 4); \
r1 = r6; \
call %[bpf_sk_release]; \
l0_%=: exit; \
" :
: __imm(bpf_sk_lookup_tcp),
__imm(bpf_sk_release),
__imm_const(__sk_buff_data, offsetof(struct __sk_buff, data)),
__imm_const(__sk_buff_data_end, offsetof(struct __sk_buff, data_end)),
__imm_const(sizeof_bpf_sock_tuple, sizeof(struct bpf_sock_tuple))
: __clobber_all);
}
SEC("tc")
__description("reference tracking: use ptr from bpf_tcp_sock() after release")
__failure __msg("invalid mem access")
__flag(BPF_F_ANY_ALIGNMENT)
__naked void bpf_tcp_sock_after_release(void)
{
asm volatile (
BPF_SK_LOOKUP(bpf_sk_lookup_tcp)
" if r0 != 0 goto l0_%=; \
exit; \
l0_%=: r6 = r0; \
r1 = r0; \
call %[bpf_tcp_sock]; \
if r0 != 0 goto l1_%=; \
r1 = r6; \
call %[bpf_sk_release]; \
exit; \
l1_%=: r7 = r0; \
r1 = r6; \
call %[bpf_sk_release]; \
r0 = *(u32*)(r7 + %[bpf_tcp_sock_snd_cwnd]); \
exit; \
" :
: __imm(bpf_sk_lookup_tcp),
__imm(bpf_sk_release),
__imm(bpf_tcp_sock),
__imm_const(bpf_tcp_sock_snd_cwnd, offsetof(struct bpf_tcp_sock, snd_cwnd)),
__imm_const(sizeof_bpf_sock_tuple, sizeof(struct bpf_sock_tuple))
: __clobber_all);
}
SEC("tc")
__description("reference tracking: use ptr from bpf_sk_fullsock() after release")
__failure __msg("invalid mem access")
__flag(BPF_F_ANY_ALIGNMENT)
__naked void bpf_sk_fullsock_after_release(void)
{
asm volatile (
BPF_SK_LOOKUP(bpf_sk_lookup_tcp)
" if r0 != 0 goto l0_%=; \
exit; \
l0_%=: r6 = r0; \
r1 = r0; \
call %[bpf_sk_fullsock]; \
if r0 != 0 goto l1_%=; \
r1 = r6; \
call %[bpf_sk_release]; \
exit; \
l1_%=: r7 = r0; \
r1 = r6; \
call %[bpf_sk_release]; \
r0 = *(u32*)(r7 + %[bpf_sock_type]); \
exit; \
" :
: __imm(bpf_sk_fullsock),
__imm(bpf_sk_lookup_tcp),
__imm(bpf_sk_release),
__imm_const(bpf_sock_type, offsetof(struct bpf_sock, type)),
__imm_const(sizeof_bpf_sock_tuple, sizeof(struct bpf_sock_tuple))
: __clobber_all);
}
SEC("tc")
__description("reference tracking: use ptr from bpf_sk_fullsock(tp) after release")
__failure __msg("invalid mem access")
__flag(BPF_F_ANY_ALIGNMENT)
__naked void sk_fullsock_tp_after_release(void)
{
asm volatile (
BPF_SK_LOOKUP(bpf_sk_lookup_tcp)
" if r0 != 0 goto l0_%=; \
exit; \
l0_%=: r6 = r0; \
r1 = r0; \
call %[bpf_tcp_sock]; \
if r0 != 0 goto l1_%=; \
r1 = r6; \
call %[bpf_sk_release]; \
exit; \
l1_%=: r1 = r0; \
call %[bpf_sk_fullsock]; \
r1 = r6; \
r6 = r0; \
call %[bpf_sk_release]; \
if r6 != 0 goto l2_%=; \
exit; \
l2_%=: r0 = *(u32*)(r6 + %[bpf_sock_type]); \
exit; \
" :
: __imm(bpf_sk_fullsock),
__imm(bpf_sk_lookup_tcp),
__imm(bpf_sk_release),
__imm(bpf_tcp_sock),
__imm_const(bpf_sock_type, offsetof(struct bpf_sock, type)),
__imm_const(sizeof_bpf_sock_tuple, sizeof(struct bpf_sock_tuple))
: __clobber_all);
}
SEC("tc")
__description("reference tracking: use sk after bpf_sk_release(tp)")
__failure __msg("invalid mem access")
__flag(BPF_F_ANY_ALIGNMENT)
__naked void after_bpf_sk_release_tp(void)
{
asm volatile (
BPF_SK_LOOKUP(bpf_sk_lookup_tcp)
" if r0 != 0 goto l0_%=; \
exit; \
l0_%=: r6 = r0; \
r1 = r0; \
call %[bpf_tcp_sock]; \
if r0 != 0 goto l1_%=; \
r1 = r6; \
call %[bpf_sk_release]; \
exit; \
l1_%=: r1 = r0; \
call %[bpf_sk_release]; \
r0 = *(u32*)(r6 + %[bpf_sock_type]); \
exit; \
" :
: __imm(bpf_sk_lookup_tcp),
__imm(bpf_sk_release),
__imm(bpf_tcp_sock),
__imm_const(bpf_sock_type, offsetof(struct bpf_sock, type)),
__imm_const(sizeof_bpf_sock_tuple, sizeof(struct bpf_sock_tuple))
: __clobber_all);
}
SEC("tc")
__description("reference tracking: use ptr from bpf_get_listener_sock() after bpf_sk_release(sk)")
__success __retval(0)
__naked void after_bpf_sk_release_sk(void)
{
asm volatile (
BPF_SK_LOOKUP(bpf_sk_lookup_tcp)
" if r0 != 0 goto l0_%=; \
exit; \
l0_%=: r6 = r0; \
r1 = r0; \
call %[bpf_get_listener_sock]; \
if r0 != 0 goto l1_%=; \
r1 = r6; \
call %[bpf_sk_release]; \
exit; \
l1_%=: r1 = r6; \
r6 = r0; \
call %[bpf_sk_release]; \
r0 = *(u32*)(r6 + %[bpf_sock_src_port]); \
exit; \
" :
: __imm(bpf_get_listener_sock),
__imm(bpf_sk_lookup_tcp),
__imm(bpf_sk_release),
__imm_const(bpf_sock_src_port, offsetof(struct bpf_sock, src_port)),
__imm_const(sizeof_bpf_sock_tuple, sizeof(struct bpf_sock_tuple))
: __clobber_all);
}
SEC("tc")
__description("reference tracking: bpf_sk_release(listen_sk)")
__failure __msg("R1 must be referenced when passed to release function")
__naked void bpf_sk_release_listen_sk(void)
{
asm volatile (
BPF_SK_LOOKUP(bpf_sk_lookup_tcp)
" if r0 != 0 goto l0_%=; \
exit; \
l0_%=: r6 = r0; \
r1 = r0; \
call %[bpf_get_listener_sock]; \
if r0 != 0 goto l1_%=; \
r1 = r6; \
call %[bpf_sk_release]; \
exit; \
l1_%=: r1 = r0; \
call %[bpf_sk_release]; \
r0 = *(u32*)(r6 + %[bpf_sock_type]); \
r1 = r6; \
call %[bpf_sk_release]; \
exit; \
" :
: __imm(bpf_get_listener_sock),
__imm(bpf_sk_lookup_tcp),
__imm(bpf_sk_release),
__imm_const(bpf_sock_type, offsetof(struct bpf_sock, type)),
__imm_const(sizeof_bpf_sock_tuple, sizeof(struct bpf_sock_tuple))
: __clobber_all);
}
/* !bpf_sk_fullsock(sk) is checked but !bpf_tcp_sock(sk) is not checked */
SEC("tc")
__description("reference tracking: tp->snd_cwnd after bpf_sk_fullsock(sk) and bpf_tcp_sock(sk)")
__failure __msg("invalid mem access")
__naked void and_bpf_tcp_sock_sk(void)
{
asm volatile (
BPF_SK_LOOKUP(bpf_sk_lookup_tcp)
" if r0 != 0 goto l0_%=; \
exit; \
l0_%=: r6 = r0; \
r1 = r0; \
call %[bpf_sk_fullsock]; \
r7 = r0; \
r1 = r6; \
call %[bpf_tcp_sock]; \
r8 = r0; \
if r7 != 0 goto l1_%=; \
r1 = r6; \
call %[bpf_sk_release]; \
exit; \
l1_%=: r0 = *(u32*)(r8 + %[bpf_tcp_sock_snd_cwnd]); \
r1 = r6; \
call %[bpf_sk_release]; \
exit; \
" :
: __imm(bpf_sk_fullsock),
__imm(bpf_sk_lookup_tcp),
__imm(bpf_sk_release),
__imm(bpf_tcp_sock),
__imm_const(bpf_tcp_sock_snd_cwnd, offsetof(struct bpf_tcp_sock, snd_cwnd)),
__imm_const(sizeof_bpf_sock_tuple, sizeof(struct bpf_sock_tuple))
: __clobber_all);
}
SEC("tc")
__description("reference tracking: branch tracking valid pointer null comparison")
__success __retval(0)
__naked void tracking_valid_pointer_null_comparison(void)
{
asm volatile (
BPF_SK_LOOKUP(bpf_sk_lookup_tcp)
" r6 = r0; \
r3 = 1; \
if r6 != 0 goto l0_%=; \
r3 = 0; \
l0_%=: if r6 == 0 goto l1_%=; \
r1 = r6; \
call %[bpf_sk_release]; \
l1_%=: exit; \
" :
: __imm(bpf_sk_lookup_tcp),
__imm(bpf_sk_release),
__imm_const(sizeof_bpf_sock_tuple, sizeof(struct bpf_sock_tuple))
: __clobber_all);
}
SEC("tc")
__description("reference tracking: branch tracking valid pointer value comparison")
__failure __msg("Unreleased reference")
__naked void tracking_valid_pointer_value_comparison(void)
{
asm volatile (
BPF_SK_LOOKUP(bpf_sk_lookup_tcp)
" r6 = r0; \
r3 = 1; \
if r6 == 0 goto l0_%=; \
r3 = 0; \
if r6 == 1234 goto l0_%=; \
r1 = r6; \
call %[bpf_sk_release]; \
l0_%=: exit; \
" :
: __imm(bpf_sk_lookup_tcp),
__imm(bpf_sk_release),
__imm_const(sizeof_bpf_sock_tuple, sizeof(struct bpf_sock_tuple))
: __clobber_all);
}
SEC("tc")
__description("reference tracking: bpf_sk_release(btf_tcp_sock)")
__success
__retval(0)
__naked void sk_release_btf_tcp_sock(void)
{
asm volatile (
BPF_SK_LOOKUP(bpf_sk_lookup_tcp)
" if r0 != 0 goto l0_%=; \
exit; \
l0_%=: r6 = r0; \
r1 = r0; \
call %[bpf_skc_to_tcp_sock]; \
if r0 != 0 goto l1_%=; \
r1 = r6; \
call %[bpf_sk_release]; \
exit; \
l1_%=: r1 = r0; \
call %[bpf_sk_release]; \
exit; \
" :
: __imm(bpf_sk_lookup_tcp),
__imm(bpf_sk_release),
__imm(bpf_skc_to_tcp_sock),
__imm_const(sizeof_bpf_sock_tuple, sizeof(struct bpf_sock_tuple))
: __clobber_all);
}
SEC("tc")
__description("reference tracking: use ptr from bpf_skc_to_tcp_sock() after release")
__failure __msg("invalid mem access")
__naked void to_tcp_sock_after_release(void)
{
asm volatile (
BPF_SK_LOOKUP(bpf_sk_lookup_tcp)
" if r0 != 0 goto l0_%=; \
exit; \
l0_%=: r6 = r0; \
r1 = r0; \
call %[bpf_skc_to_tcp_sock]; \
if r0 != 0 goto l1_%=; \
r1 = r6; \
call %[bpf_sk_release]; \
exit; \
l1_%=: r7 = r0; \
r1 = r6; \
call %[bpf_sk_release]; \
r0 = *(u8*)(r7 + 0); \
exit; \
" :
: __imm(bpf_sk_lookup_tcp),
__imm(bpf_sk_release),
__imm(bpf_skc_to_tcp_sock),
__imm_const(sizeof_bpf_sock_tuple, sizeof(struct bpf_sock_tuple))
: __clobber_all);
}
SEC("socket")
__description("reference tracking: try to leak released ptr reg")
__success __failure_unpriv __msg_unpriv("R8 !read_ok")
__retval(0)
__naked void to_leak_released_ptr_reg(void)
{
asm volatile (" \
r0 = 0; \
*(u32*)(r10 - 4) = r0; \
r2 = r10; \
r2 += -4; \
r1 = %[map_array_48b] ll; \
call %[bpf_map_lookup_elem]; \
if r0 != 0 goto l0_%=; \
exit; \
l0_%=: r9 = r0; \
r0 = 0; \
r1 = %[map_ringbuf] ll; \
r2 = 8; \
r3 = 0; \
call %[bpf_ringbuf_reserve]; \
if r0 != 0 goto l1_%=; \
exit; \
l1_%=: r8 = r0; \
r1 = r8; \
r2 = 0; \
call %[bpf_ringbuf_discard]; \
r0 = 0; \
*(u64*)(r9 + 0) = r8; \
exit; \
" :
: __imm(bpf_map_lookup_elem),
__imm(bpf_ringbuf_discard),
__imm(bpf_ringbuf_reserve),
__imm_addr(map_array_48b),
__imm_addr(map_ringbuf)
: __clobber_all);
}
char _license[] SEC("license") = "GPL";