// SPDX-License-Identifier: GPL-2.0 /* Converted from tools/testing/selftests/bpf/verifier/ref_tracking.c */ #include #include #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";