diff --git a/kernel/bpf/btf.c b/kernel/bpf/btf.c index 85ae92c920e4..5d93fd82e764 100644 --- a/kernel/bpf/btf.c +++ b/kernel/bpf/btf.c @@ -6672,6 +6672,10 @@ struct bpf_raw_tp_null_args { static const struct bpf_raw_tp_null_args raw_tp_null_args[] = { /* sched */ { "sched_pi_setprio", 0x10 }, + /* + * do_wait() passes NULL for wait4(-1) and waitid(P_ALL). + */ + { "sched_process_wait", 0x1 }, /* ... from sched_numa_pair_template event class */ { "sched_stick_numa", 0x100 }, { "sched_swap_numa", 0x100 }, @@ -6732,6 +6736,9 @@ static const struct bpf_raw_tp_null_args raw_tp_null_args[] = { { "rxrpc_resend", 0x10 }, { "rxrpc_tq", 0x10 }, { "rxrpc_client", 0x1 }, + /* signal */ + { "signal_generate", 0x20 }, + { "signal_deliver", 0x20 }, /* skb */ {"kfree_skb", 0x1000}, /* sunrpc */ diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c index 6874ba1424af..c7bc9ba9b331 100644 --- a/kernel/bpf/syscall.c +++ b/kernel/bpf/syscall.c @@ -6568,6 +6568,7 @@ EXPORT_SYMBOL_NS(kern_sys_bpf, "BPF_INTERNAL"); static const struct bpf_func_proto bpf_sys_bpf_proto = { .func = bpf_sys_bpf, .gpl_only = false, + .might_sleep = true, .ret_type = RET_INTEGER, .arg1_type = ARG_ANYTHING, .arg2_type = ARG_PTR_TO_MEM | MEM_RDONLY, @@ -6593,6 +6594,7 @@ BPF_CALL_1(bpf_sys_close, u32, fd) static const struct bpf_func_proto bpf_sys_close_proto = { .func = bpf_sys_close, .gpl_only = false, + .might_sleep = true, .ret_type = RET_INTEGER, .arg1_type = ARG_ANYTHING, }; diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c index 7d8ddb1bee00..32d31fa67036 100644 --- a/kernel/bpf/verifier.c +++ b/kernel/bpf/verifier.c @@ -11228,6 +11228,17 @@ static int check_helper_call(struct bpf_verifier_env *env, struct bpf_insn *insn if (env->cur_state->curframe) { struct bpf_verifier_state *branch; + /* + * A taken tail call is modeled as a return from the current + * frame. A callback frame cannot be left that way because + * prepare_func_exit() would apply its return contract to the + * unknown R0 synthesized below. Stack-depth validation rejects + * this construct anyway. + */ + if (cur_func(env)->in_callback_fn) { + verbose(env, "cannot tail call within callback\n"); + return -EINVAL; + } mark_reg_scratched(env, BPF_REG_0); branch = push_stack(env, env->insn_idx + 1, env->insn_idx, false); if (IS_ERR(branch)) @@ -13230,6 +13241,11 @@ static int check_kfunc_args(struct bpf_verifier_env *env, struct bpf_call_arg_me { int flags = PROCESS_RES_LOCK; + if (in_rbtree_lock_required_cb(env)) { + verbose(env, "can't res_spin_{lock,unlock} in rbtree cb\n"); + return -EACCES; + } + if (reg->type != PTR_TO_MAP_VALUE && reg->type != (PTR_TO_BTF_ID | MEM_ALLOC)) { verbose(env, "%s doesn't point to map value or allocated object\n", reg_arg_name(env, argno)); diff --git a/tools/testing/selftests/bpf/progs/raw_tp_null_fail.c b/tools/testing/selftests/bpf/progs/raw_tp_null_fail.c index 0d58114a4955..725d73c9ffe1 100644 --- a/tools/testing/selftests/bpf/progs/raw_tp_null_fail.c +++ b/tools/testing/selftests/bpf/progs/raw_tp_null_fail.c @@ -22,3 +22,56 @@ int test_raw_tp_null_sched_pi_setprio_arg_2(void *ctx) { asm volatile("r1 = *(u64 *)(r1 +8); r1 = *(u64 *)(r1 +0);" ::: __clobber_all); return 0; } + +/* Plain raw tracepoint arguments remain scalar values. */ +SEC("raw_tp/signal_generate") +__success +int test_raw_tp_signal_generate_info_scalar(void *ctx) +{ + asm volatile("r1 = *(u64 *)(r1 +8); if r1 != 1 goto +0;" ::: __clobber_all); + return 0; +} + +/* tp_btf programs may inspect the sentinel as a scalar value. */ +SEC("tp_btf/signal_generate") +__success +int test_tp_btf_signal_generate_info_scalar(void *ctx) +{ + asm volatile("r1 = *(u64 *)(r1 +8); if r1 != 1 goto +0;" ::: __clobber_all); + return 0; +} + +/* SEND_SIG_PRIV is non-NULL, so a NULL check cannot make info safe. */ +SEC("tp_btf/signal_generate") +__failure __msg("R1 invalid mem access 'scalar'") +int test_tp_btf_signal_generate_info_no_deref(void *ctx) +{ + asm volatile("r1 = *(u64 *)(r1 +8); if r1 == 0 goto +1; " + "r1 = *(u32 *)(r1 +0);" ::: __clobber_all); + return 0; +} + +SEC("tp_btf/signal_deliver") +__failure __msg("R1 invalid mem access 'scalar'") +int test_tp_btf_signal_deliver_info_no_deref(void *ctx) +{ + asm volatile("r1 = *(u64 *)(r1 +8); r1 = *(u32 *)(r1 +0);" ::: __clobber_all); + return 0; +} + +SEC("tp_btf/sched_process_wait") +__failure __msg("R1 invalid mem access 'trusted_ptr_or_null_'") +int test_raw_tp_null_sched_process_wait_arg_1(void *ctx) +{ + asm volatile("r1 = *(u64 *)(r1 +0); r1 = *(u32 *)(r1 +0);" ::: __clobber_all); + return 0; +} + +SEC("tp_btf/sched_process_wait") +__success +int test_raw_tp_null_sched_process_wait_arg_1_checked(void *ctx) +{ + asm volatile("r1 = *(u64 *)(r1 +0); if r1 == 0 goto +1; " + "r1 = *(u32 *)(r1 +0);" ::: __clobber_all); + return 0; +} diff --git a/tools/testing/selftests/bpf/progs/rbtree_fail.c b/tools/testing/selftests/bpf/progs/rbtree_fail.c index 555379952dcc..803419a47c62 100644 --- a/tools/testing/selftests/bpf/progs/rbtree_fail.c +++ b/tools/testing/selftests/bpf/progs/rbtree_fail.c @@ -16,6 +16,7 @@ struct node_data { private(A) struct bpf_spin_lock glock; private(A) struct bpf_rb_root groot __contains(node_data, node); private(A) struct bpf_rb_root groot2 __contains(node_data, node); +private(B) struct bpf_res_spin_lock res_glock; static bool less(struct bpf_rb_node *a, const struct bpf_rb_node *b) { @@ -265,6 +266,12 @@ static bool less__bad_fn_call_first_unlock_after(struct bpf_rb_node *a, const st return node_a->key < node_b->key; } +static bool less__bad_res_spin_unlock(struct bpf_rb_node *a, const struct bpf_rb_node *b) +{ + bpf_res_spin_unlock(&res_glock); + return false; +} + static __always_inline long add_with_cb(bool (cb)(struct bpf_rb_node *a, const struct bpf_rb_node *b)) { @@ -301,4 +308,26 @@ long rbtree_api_add_bad_cb_bad_fn_call_first_unlock_after(void *ctx) return add_with_cb(less__bad_fn_call_first_unlock_after); } +SEC("?tc") +__failure __msg("can't res_spin_{lock,unlock} in rbtree cb") +long rbtree_api_add_bad_cb_res_spin_unlock(void *ctx) +{ + struct node_data *n; + + n = bpf_obj_new(typeof(*n)); + if (!n) + return 1; + + bpf_spin_lock(&glock); + if (bpf_res_spin_lock(&res_glock)) { + bpf_spin_unlock(&glock); + bpf_obj_drop(n); + return 1; + } + bpf_rbtree_add(&groot, &n->node, less__bad_res_spin_unlock); + bpf_res_spin_unlock(&res_glock); + bpf_spin_unlock(&glock); + return 0; +} + char _license[] SEC("license") = "GPL"; diff --git a/tools/testing/selftests/bpf/progs/tailcall_callback.c b/tools/testing/selftests/bpf/progs/tailcall_callback.c index c41632cf423b..14fa7a87028e 100644 --- a/tools/testing/selftests/bpf/progs/tailcall_callback.c +++ b/tools/testing/selftests/bpf/progs/tailcall_callback.c @@ -44,6 +44,13 @@ int callback_loop(int index, void **cb_ctx) return ret ? 1 : 0; } +static __noinline +int callback_tail(int index, void **cb_ctx) +{ + bpf_tail_call_static(*cb_ctx, &jmp_table, 0); + return 0; +} + static __noinline int callback_empty(int index, void *data) { @@ -78,4 +85,13 @@ int tailcall_callback_2(struct __sk_buff *skb) return 0; } +/* callback with a direct tail call is rejected without a verifier bug */ +SEC("tc") +__failure __msg("cannot tail call within callback") +int tailcall_callback_3(struct __sk_buff *skb) +{ + bpf_loop(1, callback_tail, &skb, 0); + return 0; +} + char __license[] SEC("license") = "GPL"; diff --git a/tools/testing/selftests/bpf/progs/verifier_async_cb_context.c b/tools/testing/selftests/bpf/progs/verifier_async_cb_context.c index 6bf95550a024..a7c84d3fa4c7 100644 --- a/tools/testing/selftests/bpf/progs/verifier_async_cb_context.c +++ b/tools/testing/selftests/bpf/progs/verifier_async_cb_context.c @@ -62,6 +62,70 @@ int timer_sleepable_prog(void *ctx) return 0; } +static int timer_sys_bpf_cb(void *map, int *key, struct bpf_timer *timer) +{ + __u64 attr = 0; + + bpf_sys_bpf(BPF_MAP_FREEZE, &attr, sizeof(attr)); + return 0; +} + +SEC("syscall") +__failure __msg("sleepable helper bpf_sys_bpf#{{[0-9]+}} in non-sleepable prog") +int timer_sys_bpf_prog(void *ctx) +{ + struct timer_elem *val; + int key = 0; + + val = bpf_map_lookup_elem(&timer_map, &key); + if (!val) + return 0; + + bpf_timer_init(&val->t, &timer_map, 0); + bpf_timer_set_callback(&val->t, timer_sys_bpf_cb); + return 0; +} + +static int timer_sys_close_cb(void *map, int *key, struct bpf_timer *timer) +{ + bpf_sys_close(0); + return 0; +} + +SEC("syscall") +__failure __msg("sleepable helper bpf_sys_close#{{[0-9]+}} in non-sleepable prog") +int timer_sys_close_prog(void *ctx) +{ + struct timer_elem *val; + int key = 0; + + val = bpf_map_lookup_elem(&timer_map, &key); + if (!val) + return 0; + + bpf_timer_init(&val->t, &timer_map, 0); + bpf_timer_set_callback(&val->t, timer_sys_close_cb); + return 0; +} + +SEC("syscall") +__success +int syscall_sys_bpf_prog(void *ctx) +{ + __u64 attr = 0; + + bpf_sys_bpf(BPF_MAP_FREEZE, &attr, sizeof(attr)); + return 0; +} + +SEC("syscall") +__success +int syscall_sys_close_prog(void *ctx) +{ + bpf_sys_close(0); + return 0; +} + /* Workqueue tests */ struct wq_elem {