diff options
Diffstat (limited to 'tools/testing/selftests/bpf/progs/verifier_ref_tracking.c')
| -rw-r--r-- | tools/testing/selftests/bpf/progs/verifier_ref_tracking.c | 1495 |
1 files changed, 1495 insertions, 0 deletions
diff --git a/tools/testing/selftests/bpf/progs/verifier_ref_tracking.c b/tools/testing/selftests/bpf/progs/verifier_ref_tracking.c new file mode 100644 index 000000000000..c4c6da21265e --- /dev/null +++ b/tools/testing/selftests/bpf/progs/verifier_ref_tracking.c @@ -0,0 +1,1495 @@ +// 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"; |