diff options
author | Jakub Kicinski <kuba@kernel.org> | 2022-05-24 02:07:13 +0300 |
---|---|---|
committer | Jakub Kicinski <kuba@kernel.org> | 2022-05-24 02:07:14 +0300 |
commit | 1ef0736c0711e2633a59b540931406de626f2836 (patch) | |
tree | 3c230f459eda15a2263bb1fb9ac99eb0f79d802b /kernel | |
parent | 9fa87dd23251574a29cf948fd16cf39075762f3e (diff) | |
parent | 608b638ebf368f18431f47bbbd0d93828cbbdf83 (diff) |
Merge https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next
Daniel Borkmann says:
====================
pull-request: bpf-next 2022-05-23
We've added 113 non-merge commits during the last 26 day(s) which contain
a total of 121 files changed, 7425 insertions(+), 1586 deletions(-).
The main changes are:
1) Speed up symbol resolution for kprobes multi-link attachments, from Jiri Olsa.
2) Add BPF dynamic pointer infrastructure e.g. to allow for dynamically sized ringbuf
reservations without extra memory copies, from Joanne Koong.
3) Big batch of libbpf improvements towards libbpf 1.0 release, from Andrii Nakryiko.
4) Add BPF link iterator to traverse links via seq_file ops, from Dmitrii Dolgov.
5) Add source IP address to BPF tunnel key infrastructure, from Kaixi Fan.
6) Refine unprivileged BPF to disable only object-creating commands, from Alan Maguire.
7) Fix JIT blinding of ld_imm64 when they point to subprogs, from Alexei Starovoitov.
8) Add BPF access to mptcp_sock structures and their meta data, from Geliang Tang.
9) Add new BPF helper for access to remote CPU's BPF map elements, from Feng Zhou.
10) Allow attaching 64-bit cookie to BPF link of fentry/fexit/fmod_ret, from Kui-Feng Lee.
11) Follow-ups to typed pointer support in BPF maps, from Kumar Kartikeya Dwivedi.
12) Add busy-poll test cases to the XSK selftest suite, from Magnus Karlsson.
13) Improvements in BPF selftest test_progs subtest output, from Mykola Lysenko.
14) Fill bpf_prog_pack allocator areas with illegal instructions, from Song Liu.
15) Add generic batch operations for BPF map-in-map cases, from Takshak Chahande.
16) Make bpf_jit_enable more user friendly when permanently on 1, from Tiezhu Yang.
17) Fix an array overflow in bpf_trampoline_get_progs(), from Yuntao Wang.
====================
Link: https://lore.kernel.org/r/20220523223805.27931-1-daniel@iogearbox.net
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Diffstat (limited to 'kernel')
-rw-r--r-- | kernel/bpf/Makefile | 2 | ||||
-rw-r--r-- | kernel/bpf/arraymap.c | 17 | ||||
-rw-r--r-- | kernel/bpf/bpf_lsm.c | 17 | ||||
-rw-r--r-- | kernel/bpf/bpf_struct_ops.c | 71 | ||||
-rw-r--r-- | kernel/bpf/btf.c | 6 | ||||
-rw-r--r-- | kernel/bpf/core.c | 29 | ||||
-rw-r--r-- | kernel/bpf/hashtab.c | 45 | ||||
-rw-r--r-- | kernel/bpf/helpers.c | 199 | ||||
-rw-r--r-- | kernel/bpf/link_iter.c | 107 | ||||
-rw-r--r-- | kernel/bpf/ringbuf.c | 78 | ||||
-rw-r--r-- | kernel/bpf/syscall.c | 75 | ||||
-rw-r--r-- | kernel/bpf/trampoline.c | 118 | ||||
-rw-r--r-- | kernel/bpf/verifier.c | 324 | ||||
-rw-r--r-- | kernel/kallsyms.c | 3 | ||||
-rw-r--r-- | kernel/trace/bpf_trace.c | 133 | ||||
-rw-r--r-- | kernel/trace/fprobe.c | 32 | ||||
-rw-r--r-- | kernel/trace/ftrace.c | 62 |
17 files changed, 1120 insertions, 198 deletions
diff --git a/kernel/bpf/Makefile b/kernel/bpf/Makefile index c1a9be6a4b9f..057ba8e01e70 100644 --- a/kernel/bpf/Makefile +++ b/kernel/bpf/Makefile @@ -6,7 +6,7 @@ cflags-nogcse-$(CONFIG_X86)$(CONFIG_CC_IS_GCC) := -fno-gcse endif CFLAGS_core.o += $(call cc-disable-warning, override-init) $(cflags-nogcse-yy) -obj-$(CONFIG_BPF_SYSCALL) += syscall.o verifier.o inode.o helpers.o tnum.o bpf_iter.o map_iter.o task_iter.o prog_iter.o +obj-$(CONFIG_BPF_SYSCALL) += syscall.o verifier.o inode.o helpers.o tnum.o bpf_iter.o map_iter.o task_iter.o prog_iter.o link_iter.o obj-$(CONFIG_BPF_SYSCALL) += hashtab.o arraymap.o percpu_freelist.o bpf_lru_list.o lpm_trie.o map_in_map.o bloom_filter.o obj-$(CONFIG_BPF_SYSCALL) += local_storage.o queue_stack_maps.o ringbuf.o obj-$(CONFIG_BPF_SYSCALL) += bpf_local_storage.o bpf_task_storage.o diff --git a/kernel/bpf/arraymap.c b/kernel/bpf/arraymap.c index b3bf31fd9458..fe40d3b9458f 100644 --- a/kernel/bpf/arraymap.c +++ b/kernel/bpf/arraymap.c @@ -243,6 +243,20 @@ static void *percpu_array_map_lookup_elem(struct bpf_map *map, void *key) return this_cpu_ptr(array->pptrs[index & array->index_mask]); } +static void *percpu_array_map_lookup_percpu_elem(struct bpf_map *map, void *key, u32 cpu) +{ + struct bpf_array *array = container_of(map, struct bpf_array, map); + u32 index = *(u32 *)key; + + if (cpu >= nr_cpu_ids) + return NULL; + + if (unlikely(index >= array->map.max_entries)) + return NULL; + + return per_cpu_ptr(array->pptrs[index & array->index_mask], cpu); +} + int bpf_percpu_array_copy(struct bpf_map *map, void *key, void *value) { struct bpf_array *array = container_of(map, struct bpf_array, map); @@ -725,6 +739,7 @@ const struct bpf_map_ops percpu_array_map_ops = { .map_lookup_elem = percpu_array_map_lookup_elem, .map_update_elem = array_map_update_elem, .map_delete_elem = array_map_delete_elem, + .map_lookup_percpu_elem = percpu_array_map_lookup_percpu_elem, .map_seq_show_elem = percpu_array_map_seq_show_elem, .map_check_btf = array_map_check_btf, .map_lookup_batch = generic_map_lookup_batch, @@ -1345,6 +1360,8 @@ const struct bpf_map_ops array_of_maps_map_ops = { .map_fd_put_ptr = bpf_map_fd_put_ptr, .map_fd_sys_lookup_elem = bpf_map_fd_sys_lookup_elem, .map_gen_lookup = array_of_map_gen_lookup, + .map_lookup_batch = generic_map_lookup_batch, + .map_update_batch = generic_map_update_batch, .map_check_btf = map_check_no_btf, .map_btf_id = &array_map_btf_ids[0], }; diff --git a/kernel/bpf/bpf_lsm.c b/kernel/bpf/bpf_lsm.c index 064eccba641d..c1351df9f7ee 100644 --- a/kernel/bpf/bpf_lsm.c +++ b/kernel/bpf/bpf_lsm.c @@ -117,6 +117,21 @@ static const struct bpf_func_proto bpf_ima_file_hash_proto = { .allowed = bpf_ima_inode_hash_allowed, }; +BPF_CALL_1(bpf_get_attach_cookie, void *, ctx) +{ + struct bpf_trace_run_ctx *run_ctx; + + run_ctx = container_of(current->bpf_ctx, struct bpf_trace_run_ctx, run_ctx); + return run_ctx->bpf_cookie; +} + +static const struct bpf_func_proto bpf_get_attach_cookie_proto = { + .func = bpf_get_attach_cookie, + .gpl_only = false, + .ret_type = RET_INTEGER, + .arg1_type = ARG_PTR_TO_CTX, +}; + static const struct bpf_func_proto * bpf_lsm_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) { @@ -141,6 +156,8 @@ bpf_lsm_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) return prog->aux->sleepable ? &bpf_ima_inode_hash_proto : NULL; case BPF_FUNC_ima_file_hash: return prog->aux->sleepable ? &bpf_ima_file_hash_proto : NULL; + case BPF_FUNC_get_attach_cookie: + return bpf_prog_has_trampoline(prog) ? &bpf_get_attach_cookie_proto : NULL; default: return tracing_prog_func_proto(func_id, prog); } diff --git a/kernel/bpf/bpf_struct_ops.c b/kernel/bpf/bpf_struct_ops.c index 3a0103ad97bc..d9a3c9207240 100644 --- a/kernel/bpf/bpf_struct_ops.c +++ b/kernel/bpf/bpf_struct_ops.c @@ -33,15 +33,15 @@ struct bpf_struct_ops_map { const struct bpf_struct_ops *st_ops; /* protect map_update */ struct mutex lock; - /* progs has all the bpf_prog that is populated + /* link has all the bpf_links that is populated * to the func ptr of the kernel's struct * (in kvalue.data). */ - struct bpf_prog **progs; + struct bpf_link **links; /* image is a page that has all the trampolines * that stores the func args before calling the bpf_prog. * A PAGE_SIZE "image" is enough to store all trampoline for - * "progs[]". + * "links[]". */ void *image; /* uvalue->data stores the kernel struct @@ -283,9 +283,9 @@ static void bpf_struct_ops_map_put_progs(struct bpf_struct_ops_map *st_map) u32 i; for (i = 0; i < btf_type_vlen(t); i++) { - if (st_map->progs[i]) { - bpf_prog_put(st_map->progs[i]); - st_map->progs[i] = NULL; + if (st_map->links[i]) { + bpf_link_put(st_map->links[i]); + st_map->links[i] = NULL; } } } @@ -316,18 +316,34 @@ static int check_zero_holes(const struct btf_type *t, void *data) return 0; } -int bpf_struct_ops_prepare_trampoline(struct bpf_tramp_progs *tprogs, - struct bpf_prog *prog, +static void bpf_struct_ops_link_release(struct bpf_link *link) +{ +} + +static void bpf_struct_ops_link_dealloc(struct bpf_link *link) +{ + struct bpf_tramp_link *tlink = container_of(link, struct bpf_tramp_link, link); + + kfree(tlink); +} + +const struct bpf_link_ops bpf_struct_ops_link_lops = { + .release = bpf_struct_ops_link_release, + .dealloc = bpf_struct_ops_link_dealloc, +}; + +int bpf_struct_ops_prepare_trampoline(struct bpf_tramp_links *tlinks, + struct bpf_tramp_link *link, const struct btf_func_model *model, void *image, void *image_end) { u32 flags; - tprogs[BPF_TRAMP_FENTRY].progs[0] = prog; - tprogs[BPF_TRAMP_FENTRY].nr_progs = 1; + tlinks[BPF_TRAMP_FENTRY].links[0] = link; + tlinks[BPF_TRAMP_FENTRY].nr_links = 1; flags = model->ret_size > 0 ? BPF_TRAMP_F_RET_FENTRY_RET : 0; return arch_prepare_bpf_trampoline(NULL, image, image_end, - model, flags, tprogs, NULL); + model, flags, tlinks, NULL); } static int bpf_struct_ops_map_update_elem(struct bpf_map *map, void *key, @@ -338,7 +354,7 @@ static int bpf_struct_ops_map_update_elem(struct bpf_map *map, void *key, struct bpf_struct_ops_value *uvalue, *kvalue; const struct btf_member *member; const struct btf_type *t = st_ops->type; - struct bpf_tramp_progs *tprogs = NULL; + struct bpf_tramp_links *tlinks = NULL; void *udata, *kdata; int prog_fd, err = 0; void *image, *image_end; @@ -362,8 +378,8 @@ static int bpf_struct_ops_map_update_elem(struct bpf_map *map, void *key, if (uvalue->state || refcount_read(&uvalue->refcnt)) return -EINVAL; - tprogs = kcalloc(BPF_TRAMP_MAX, sizeof(*tprogs), GFP_KERNEL); - if (!tprogs) + tlinks = kcalloc(BPF_TRAMP_MAX, sizeof(*tlinks), GFP_KERNEL); + if (!tlinks) return -ENOMEM; uvalue = (struct bpf_struct_ops_value *)st_map->uvalue; @@ -386,6 +402,7 @@ static int bpf_struct_ops_map_update_elem(struct bpf_map *map, void *key, for_each_member(i, t, member) { const struct btf_type *mtype, *ptype; struct bpf_prog *prog; + struct bpf_tramp_link *link; u32 moff; moff = __btf_member_bit_offset(t, member) / 8; @@ -439,16 +456,26 @@ static int bpf_struct_ops_map_update_elem(struct bpf_map *map, void *key, err = PTR_ERR(prog); goto reset_unlock; } - st_map->progs[i] = prog; if (prog->type != BPF_PROG_TYPE_STRUCT_OPS || prog->aux->attach_btf_id != st_ops->type_id || prog->expected_attach_type != i) { + bpf_prog_put(prog); err = -EINVAL; goto reset_unlock; } - err = bpf_struct_ops_prepare_trampoline(tprogs, prog, + link = kzalloc(sizeof(*link), GFP_USER); + if (!link) { + bpf_prog_put(prog); + err = -ENOMEM; + goto reset_unlock; + } + bpf_link_init(&link->link, BPF_LINK_TYPE_STRUCT_OPS, + &bpf_struct_ops_link_lops, prog); + st_map->links[i] = &link->link; + + err = bpf_struct_ops_prepare_trampoline(tlinks, link, &st_ops->func_models[i], image, image_end); if (err < 0) @@ -491,7 +518,7 @@ reset_unlock: memset(uvalue, 0, map->value_size); memset(kvalue, 0, map->value_size); unlock: - kfree(tprogs); + kfree(tlinks); mutex_unlock(&st_map->lock); return err; } @@ -546,9 +573,9 @@ static void bpf_struct_ops_map_free(struct bpf_map *map) { struct bpf_struct_ops_map *st_map = (struct bpf_struct_ops_map *)map; - if (st_map->progs) + if (st_map->links) bpf_struct_ops_map_put_progs(st_map); - bpf_map_area_free(st_map->progs); + bpf_map_area_free(st_map->links); bpf_jit_free_exec(st_map->image); bpf_map_area_free(st_map->uvalue); bpf_map_area_free(st_map); @@ -597,11 +624,11 @@ static struct bpf_map *bpf_struct_ops_map_alloc(union bpf_attr *attr) map = &st_map->map; st_map->uvalue = bpf_map_area_alloc(vt->size, NUMA_NO_NODE); - st_map->progs = - bpf_map_area_alloc(btf_type_vlen(t) * sizeof(struct bpf_prog *), + st_map->links = + bpf_map_area_alloc(btf_type_vlen(t) * sizeof(struct bpf_links *), NUMA_NO_NODE); st_map->image = bpf_jit_alloc_exec(PAGE_SIZE); - if (!st_map->uvalue || !st_map->progs || !st_map->image) { + if (!st_map->uvalue || !st_map->links || !st_map->image) { bpf_struct_ops_map_free(map); return ERR_PTR(-ENOMEM); } diff --git a/kernel/bpf/btf.c b/kernel/bpf/btf.c index 2f0b0440131c..7bccaa4646e5 100644 --- a/kernel/bpf/btf.c +++ b/kernel/bpf/btf.c @@ -202,6 +202,8 @@ enum btf_kfunc_hook { BTF_KFUNC_HOOK_XDP, BTF_KFUNC_HOOK_TC, BTF_KFUNC_HOOK_STRUCT_OPS, + BTF_KFUNC_HOOK_TRACING, + BTF_KFUNC_HOOK_SYSCALL, BTF_KFUNC_HOOK_MAX, }; @@ -7110,6 +7112,10 @@ static int bpf_prog_type_to_kfunc_hook(enum bpf_prog_type prog_type) return BTF_KFUNC_HOOK_TC; case BPF_PROG_TYPE_STRUCT_OPS: return BTF_KFUNC_HOOK_STRUCT_OPS; + case BPF_PROG_TYPE_TRACING: + return BTF_KFUNC_HOOK_TRACING; + case BPF_PROG_TYPE_SYSCALL: + return BTF_KFUNC_HOOK_SYSCALL; default: return BTF_KFUNC_HOOK_MAX; } diff --git a/kernel/bpf/core.c b/kernel/bpf/core.c index 13e9dbeeedf3..cacd8684c3c4 100644 --- a/kernel/bpf/core.c +++ b/kernel/bpf/core.c @@ -873,7 +873,7 @@ static size_t select_bpf_prog_pack_size(void) return size; } -static struct bpf_prog_pack *alloc_new_pack(void) +static struct bpf_prog_pack *alloc_new_pack(bpf_jit_fill_hole_t bpf_fill_ill_insns) { struct bpf_prog_pack *pack; @@ -886,6 +886,7 @@ static struct bpf_prog_pack *alloc_new_pack(void) kfree(pack); return NULL; } + bpf_fill_ill_insns(pack->ptr, bpf_prog_pack_size); bitmap_zero(pack->bitmap, bpf_prog_pack_size / BPF_PROG_CHUNK_SIZE); list_add_tail(&pack->list, &pack_list); @@ -895,7 +896,7 @@ static struct bpf_prog_pack *alloc_new_pack(void) return pack; } -static void *bpf_prog_pack_alloc(u32 size) +static void *bpf_prog_pack_alloc(u32 size, bpf_jit_fill_hole_t bpf_fill_ill_insns) { unsigned int nbits = BPF_PROG_SIZE_TO_NBITS(size); struct bpf_prog_pack *pack; @@ -910,6 +911,7 @@ static void *bpf_prog_pack_alloc(u32 size) size = round_up(size, PAGE_SIZE); ptr = module_alloc(size); if (ptr) { + bpf_fill_ill_insns(ptr, size); set_vm_flush_reset_perms(ptr); set_memory_ro((unsigned long)ptr, size / PAGE_SIZE); set_memory_x((unsigned long)ptr, size / PAGE_SIZE); @@ -923,7 +925,7 @@ static void *bpf_prog_pack_alloc(u32 size) goto found_free_area; } - pack = alloc_new_pack(); + pack = alloc_new_pack(bpf_fill_ill_insns); if (!pack) goto out; @@ -966,6 +968,9 @@ static void bpf_prog_pack_free(struct bpf_binary_header *hdr) nbits = BPF_PROG_SIZE_TO_NBITS(hdr->size); pos = ((unsigned long)hdr - (unsigned long)pack_ptr) >> BPF_PROG_CHUNK_SHIFT; + WARN_ONCE(bpf_arch_text_invalidate(hdr, hdr->size), + "bpf_prog_pack bug: missing bpf_arch_text_invalidate?\n"); + bitmap_clear(pack->bitmap, pos, nbits); if (bitmap_find_next_zero_area(pack->bitmap, bpf_prog_chunk_count(), 0, bpf_prog_chunk_count(), 0) == 0) { @@ -1102,7 +1107,7 @@ bpf_jit_binary_pack_alloc(unsigned int proglen, u8 **image_ptr, if (bpf_jit_charge_modmem(size)) return NULL; - ro_header = bpf_prog_pack_alloc(size); + ro_header = bpf_prog_pack_alloc(size, bpf_fill_ill_insns); if (!ro_header) { bpf_jit_uncharge_modmem(size); return NULL; @@ -1434,6 +1439,16 @@ struct bpf_prog *bpf_jit_blind_constants(struct bpf_prog *prog) insn = clone->insnsi; for (i = 0; i < insn_cnt; i++, insn++) { + if (bpf_pseudo_func(insn)) { + /* ld_imm64 with an address of bpf subprog is not + * a user controlled constant. Don't randomize it, + * since it will conflict with jit_subprogs() logic. + */ + insn++; + i++; + continue; + } + /* We temporarily need to hold the original ld64 insn * so that we can still access the first part in the * second blinding run. @@ -2619,6 +2634,7 @@ const struct bpf_func_proto bpf_map_delete_elem_proto __weak; const struct bpf_func_proto bpf_map_push_elem_proto __weak; const struct bpf_func_proto bpf_map_pop_elem_proto __weak; const struct bpf_func_proto bpf_map_peek_elem_proto __weak; +const struct bpf_func_proto bpf_map_lookup_percpu_elem_proto __weak; const struct bpf_func_proto bpf_spin_lock_proto __weak; const struct bpf_func_proto bpf_spin_unlock_proto __weak; const struct bpf_func_proto bpf_jiffies64_proto __weak; @@ -2727,6 +2743,11 @@ void * __weak bpf_arch_text_copy(void *dst, void *src, size_t len) return ERR_PTR(-ENOTSUPP); } +int __weak bpf_arch_text_invalidate(void *dst, size_t len) +{ + return -ENOTSUPP; +} + DEFINE_STATIC_KEY_FALSE(bpf_stats_enabled_key); EXPORT_SYMBOL(bpf_stats_enabled_key); diff --git a/kernel/bpf/hashtab.c b/kernel/bpf/hashtab.c index 3e00e62b2218..17fb69c0e0dc 100644 --- a/kernel/bpf/hashtab.c +++ b/kernel/bpf/hashtab.c @@ -140,7 +140,7 @@ static inline bool htab_use_raw_lock(const struct bpf_htab *htab) static void htab_init_buckets(struct bpf_htab *htab) { - unsigned i; + unsigned int i; for (i = 0; i < htab->n_buckets; i++) { INIT_HLIST_NULLS_HEAD(&htab->buckets[i].head, i); @@ -1627,7 +1627,7 @@ __htab_map_lookup_and_delete_batch(struct bpf_map *map, void __user *uvalues = u64_to_user_ptr(attr->batch.values); void __user *ukeys = u64_to_user_ptr(attr->batch.keys); void __user *ubatch = u64_to_user_ptr(attr->batch.in_batch); - u32 batch, max_count, size, bucket_size; + u32 batch, max_count, size, bucket_size, map_id; struct htab_elem *node_to_free = NULL; u64 elem_map_flags, map_flags; struct hlist_nulls_head *head; @@ -1752,6 +1752,14 @@ again_nocopy: } } else { value = l->key + roundup_key_size; + if (map->map_type == BPF_MAP_TYPE_HASH_OF_MAPS) { + struct bpf_map **inner_map = value; + + /* Actual value is the id of the inner map */ + map_id = map->ops->map_fd_sys_lookup_elem(*inner_map); + value = &map_id; + } + if (elem_map_flags & BPF_F_LOCK) copy_map_value_locked(map, dst_val, value, true); @@ -2191,6 +2199,20 @@ static void *htab_percpu_map_lookup_elem(struct bpf_map *map, void *key) return NULL; } +static void *htab_percpu_map_lookup_percpu_elem(struct bpf_map *map, void *key, u32 cpu) +{ + struct htab_elem *l; + + if (cpu >= nr_cpu_ids) + return NULL; + + l = __htab_map_lookup_elem(map, key); + if (l) + return per_cpu_ptr(htab_elem_get_ptr(l, map->key_size), cpu); + else + return NULL; +} + static void *htab_lru_percpu_map_lookup_elem(struct bpf_map *map, void *key) { struct htab_elem *l = __htab_map_lookup_elem(map, key); @@ -2203,6 +2225,22 @@ static void *htab_lru_percpu_map_lookup_elem(struct bpf_map *map, void *key) return NULL; } +static void *htab_lru_percpu_map_lookup_percpu_elem(struct bpf_map *map, void *key, u32 cpu) +{ + struct htab_elem *l; + + if (cpu >= nr_cpu_ids) + return NULL; + + l = __htab_map_lookup_elem(map, key); + if (l) { + bpf_lru_node_set_ref(&l->lru_node); + return per_cpu_ptr(htab_elem_get_ptr(l, map->key_size), cpu); + } + + return NULL; +} + int bpf_percpu_hash_copy(struct bpf_map *map, void *key, void *value) { struct htab_elem *l; @@ -2292,6 +2330,7 @@ const struct bpf_map_ops htab_percpu_map_ops = { .map_lookup_and_delete_elem = htab_percpu_map_lookup_and_delete_elem, .map_update_elem = htab_percpu_map_update_elem, .map_delete_elem = htab_map_delete_elem, + .map_lookup_percpu_elem = htab_percpu_map_lookup_percpu_elem, .map_seq_show_elem = htab_percpu_map_seq_show_elem, .map_set_for_each_callback_args = map_set_for_each_callback_args, .map_for_each_callback = bpf_for_each_hash_elem, @@ -2310,6 +2349,7 @@ const struct bpf_map_ops htab_lru_percpu_map_ops = { .map_lookup_and_delete_elem = htab_lru_percpu_map_lookup_and_delete_elem, .map_update_elem = htab_lru_percpu_map_update_elem, .map_delete_elem = htab_lru_map_delete_elem, + .map_lookup_percpu_elem = htab_lru_percpu_map_lookup_percpu_elem, .map_seq_show_elem = htab_percpu_map_seq_show_elem, .map_set_for_each_callback_args = map_set_for_each_callback_args, .map_for_each_callback = bpf_for_each_hash_elem, @@ -2450,5 +2490,6 @@ const struct bpf_map_ops htab_of_maps_map_ops = { .map_fd_sys_lookup_elem = bpf_map_fd_sys_lookup_elem, .map_gen_lookup = htab_of_map_gen_lookup, .map_check_btf = map_check_no_btf, + BATCH_OPS(htab), .map_btf_id = &htab_map_btf_ids[0], }; diff --git a/kernel/bpf/helpers.c b/kernel/bpf/helpers.c index 3e709fed5306..225806a02efb 100644 --- a/kernel/bpf/helpers.c +++ b/kernel/bpf/helpers.c @@ -103,7 +103,7 @@ const struct bpf_func_proto bpf_map_pop_elem_proto = { .gpl_only = false, .ret_type = RET_INTEGER, .arg1_type = ARG_CONST_MAP_PTR, - .arg2_type = ARG_PTR_TO_UNINIT_MAP_VALUE, + .arg2_type = ARG_PTR_TO_MAP_VALUE | MEM_UNINIT, }; BPF_CALL_2(bpf_map_peek_elem, struct bpf_map *, map, void *, value) @@ -116,7 +116,23 @@ const struct bpf_func_proto bpf_map_peek_elem_proto = { .gpl_only = false, .ret_type = RET_INTEGER, .arg1_type = ARG_CONST_MAP_PTR, - .arg2_type = ARG_PTR_TO_UNINIT_MAP_VALUE, + .arg2_type = ARG_PTR_TO_MAP_VALUE | MEM_UNINIT, +}; + +BPF_CALL_3(bpf_map_lookup_percpu_elem, struct bpf_map *, map, void *, key, u32, cpu) +{ + WARN_ON_ONCE(!rcu_read_lock_held() && !rcu_read_lock_bh_held()); + return (unsigned long) map->ops->map_lookup_percpu_elem(map, key, cpu); +} + +const struct bpf_func_proto bpf_map_lookup_percpu_elem_proto = { + .func = bpf_map_lookup_percpu_elem, + .gpl_only = false, + .pkt_access = true, + .ret_type = RET_PTR_TO_MAP_VALUE_OR_NULL, + .arg1_type = ARG_CONST_MAP_PTR, + .arg2_type = ARG_PTR_TO_MAP_KEY, + .arg3_type = ARG_ANYTHING, }; const struct bpf_func_proto bpf_get_prandom_u32_proto = { @@ -1396,6 +1412,169 @@ const struct bpf_func_proto bpf_kptr_xchg_proto = { .arg2_btf_id = BPF_PTR_POISON, }; +/* Since the upper 8 bits of dynptr->size is reserved, the + * maximum supported size is 2^24 - 1. + */ +#define DYNPTR_MAX_SIZE ((1UL << 24) - 1) +#define DYNPTR_TYPE_SHIFT 28 +#define DYNPTR_SIZE_MASK 0xFFFFFF +#define DYNPTR_RDONLY_BIT BIT(31) + +static bool bpf_dynptr_is_rdonly(struct bpf_dynptr_kern *ptr) +{ + return ptr->size & DYNPTR_RDONLY_BIT; +} + +static void bpf_dynptr_set_type(struct bpf_dynptr_kern *ptr, enum bpf_dynptr_type type) +{ + ptr->size |= type << DYNPTR_TYPE_SHIFT; +} + +static u32 bpf_dynptr_get_size(struct bpf_dynptr_kern *ptr) +{ + return ptr->size & DYNPTR_SIZE_MASK; +} + +int bpf_dynptr_check_size(u32 size) +{ + return size > DYNPTR_MAX_SIZE ? -E2BIG : 0; +} + +void bpf_dynptr_init(struct bpf_dynptr_kern *ptr, void *data, + enum bpf_dynptr_type type, u32 offset, u32 size) +{ + ptr->data = data; + ptr->offset = offset; + ptr->size = size; + bpf_dynptr_set_type(ptr, type); +} + +void bpf_dynptr_set_null(struct bpf_dynptr_kern *ptr) +{ + memset(ptr, 0, sizeof(*ptr)); +} + +static int bpf_dynptr_check_off_len(struct bpf_dynptr_kern *ptr, u32 offset, u32 len) +{ + u32 size = bpf_dynptr_get_size(ptr); + + if (len > size || offset > size - len) + return -E2BIG; + + return 0; +} + +BPF_CALL_4(bpf_dynptr_from_mem, void *, data, u32, size, u64, flags, struct bpf_dynptr_kern *, ptr) +{ + int err; + + err = bpf_dynptr_check_size(size); + if (err) + goto error; + + /* flags is currently unsupported */ + if (flags) { + err = -EINVAL; + goto error; + } + + bpf_dynptr_init(ptr, data, BPF_DYNPTR_TYPE_LOCAL, 0, size); + + return 0; + +error: + bpf_dynptr_set_null(ptr); + return err; +} + +const struct bpf_func_proto bpf_dynptr_from_mem_proto = { + .func = bpf_dynptr_from_mem, + .gpl_only = false, + .ret_type = RET_INTEGER, + .arg1_type = ARG_PTR_TO_UNINIT_MEM, + .arg2_type = ARG_CONST_SIZE_OR_ZERO, + .arg3_type = ARG_ANYTHING, + .arg4_type = ARG_PTR_TO_DYNPTR | DYNPTR_TYPE_LOCAL | MEM_UNINIT, +}; + +BPF_CALL_4(bpf_dynptr_read, void *, dst, u32, len, struct bpf_dynptr_kern *, src, u32, offset) +{ + int err; + + if (!src->data) + return -EINVAL; + + err = bpf_dynptr_check_off_len(src, offset, len); + if (err) + return err; + + memcpy(dst, src->data + src->offset + offset, len); + + return 0; +} + +const struct bpf_func_proto bpf_dynptr_read_proto = { + .func = bpf_dynptr_read, + .gpl_only = false, + .ret_type = RET_INTEGER, + .arg1_type = ARG_PTR_TO_UNINIT_MEM, + .arg2_type = ARG_CONST_SIZE_OR_ZERO, + .arg3_type = ARG_PTR_TO_DYNPTR, + .arg4_type = ARG_ANYTHING, +}; + +BPF_CALL_4(bpf_dynptr_write, struct bpf_dynptr_kern *, dst, u32, offset, void *, src, u32, len) +{ + int err; + + if (!dst->data || bpf_dynptr_is_rdonly(dst)) + return -EINVAL; + + err = bpf_dynptr_check_off_len(dst, offset, len); + if (err) + return err; + + memcpy(dst->data + dst->offset + offset, src, len); + + return 0; +} + +const struct bpf_func_proto bpf_dynptr_write_proto = { + .func = bpf_dynptr_write, + .gpl_only = false, + .ret_type = RET_INTEGER, + .arg1_type = ARG_PTR_TO_DYNPTR, + .arg2_type = ARG_ANYTHING, + .arg3_type = ARG_PTR_TO_MEM | MEM_RDONLY, + .arg4_type = ARG_CONST_SIZE_OR_ZERO, +}; + +BPF_CALL_3(bpf_dynptr_data, struct bpf_dynptr_kern *, ptr, u32, offset, u32, len) +{ + int err; + + if (!ptr->data) + return 0; + + err = bpf_dynptr_check_off_len(ptr, offset, len); + if (err) + return 0; + + if (bpf_dynptr_is_rdonly(ptr)) + return 0; + + return (unsigned long)(ptr->data + ptr->offset + offset); +} + +const struct bpf_func_proto bpf_dynptr_data_proto = { + .func = bpf_dynptr_data, + .gpl_only = false, + .ret_type = RET_PTR_TO_DYNPTR_MEM_OR_NULL, + .arg1_type = ARG_PTR_TO_DYNPTR, + .arg2_type = ARG_ANYTHING, + .arg3_type = ARG_CONST_ALLOC_SIZE_OR_ZERO, +}; + const struct bpf_func_proto bpf_get_current_task_proto __weak; const struct bpf_func_proto bpf_get_current_task_btf_proto __weak; const struct bpf_func_proto bpf_probe_read_user_proto __weak; @@ -1420,6 +1599,8 @@ bpf_base_func_proto(enum bpf_func_id func_id) return &bpf_map_pop_elem_proto; case BPF_FUNC_map_peek_elem: return &bpf_map_peek_elem_proto; + case BPF_FUNC_map_lookup_percpu_elem: + return &bpf_map_lookup_percpu_elem_proto; case BPF_FUNC_get_prandom_u32: return &bpf_get_prandom_u32_proto; case BPF_FUNC_get_smp_processor_id: @@ -1442,12 +1623,26 @@ bpf_base_func_proto(enum bpf_func_id func_id) return &bpf_ringbuf_discard_proto; case BPF_FUNC_ringbuf_query: return &bpf_ringbuf_query_proto; + case BPF_FUNC_ringbuf_reserve_dynptr: + return &bpf_ringbuf_reserve_dynptr_proto; + case BPF_FUNC_ringbuf_submit_dynptr: + return &bpf_ringbuf_submit_dynptr_proto; + case BPF_FUNC_ringbuf_discard_dynptr: + return &bpf_ringbuf_discard_dynptr_proto; case BPF_FUNC_for_each_map_elem: return &bpf_for_each_map_elem_proto; case BPF_FUNC_loop: return &bpf_loop_proto; case BPF_FUNC_strncmp: return &bpf_strncmp_proto; + case BPF_FUNC_dynptr_from_mem: + return &bpf_dynptr_from_mem_proto; + case BPF_FUNC_dynptr_read: + return &bpf_dynptr_read_proto; + case BPF_FUNC_dynptr_write: + return &bpf_dynptr_write_proto; + case BPF_FUNC_dynptr_data: + return &bpf_dynptr_data_proto; default: break; } diff --git a/kernel/bpf/link_iter.c b/kernel/bpf/link_iter.c new file mode 100644 index 000000000000..fec8005a121c --- /dev/null +++ b/kernel/bpf/link_iter.c @@ -0,0 +1,107 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* Copyright (c) 2022 Red Hat, Inc. */ +#include <linux/bpf.h> +#include <linux/fs.h> +#include <linux/filter.h> +#include <linux/kernel.h> +#include <linux/btf_ids.h> + +struct bpf_iter_seq_link_info { + u32 link_id; +}; + +static void *bpf_link_seq_start(struct seq_file *seq, loff_t *pos) +{ + struct bpf_iter_seq_link_info *info = seq->private; + struct bpf_link *link; + + link = bpf_link_get_curr_or_next(&info->link_id); + if (!link) + return NULL; + + if (*pos == 0) + ++*pos; + return link; +} + +static void *bpf_link_seq_next(struct seq_file *seq, void *v, loff_t *pos) +{ + struct bpf_iter_seq_link_info *info = seq->private; + + ++*pos; + ++info->link_id; + bpf_link_put((struct bpf_link *)v); + return bpf_link_get_curr_or_next(&info->link_id); +} + +struct bpf_iter__bpf_link { + __bpf_md_ptr(struct bpf_iter_meta *, meta); + __bpf_md_ptr(struct bpf_link *, link); +}; + +DEFINE_BPF_ITER_FUNC(bpf_link, struct bpf_iter_meta *meta, struct bpf_link *link) + +static int __bpf_link_seq_show(struct seq_file *seq, void *v, bool in_stop) +{ + struct bpf_iter__bpf_link ctx; + struct bpf_iter_meta meta; + struct bpf_prog *prog; + int ret = 0; + + ctx.meta = &meta; + ctx.link = v; + meta.seq = seq; + prog = bpf_iter_get_info(&meta, in_stop); + if (prog) + ret = bpf_iter_run_prog(prog, &ctx); + + return ret; +} + +static int bpf_link_seq_show(struct seq_file *seq, void *v) +{ + return __bpf_link_seq_show(seq, v, false); +} + +static void bpf_link_seq_stop(struct seq_file *seq, void *v) +{ + if (!v) + (void)__bpf_link_seq_show(seq, v, true); + else + bpf_link_put((struct bpf_link *)v); +} + +static const struct seq_operations bpf_link_seq_ops = { + .start = bpf_link_seq_start, + .next = bpf_link_seq_next, + .stop = bpf_link_seq_stop, + .show = bpf_link_seq_show, +}; + +BTF_ID_LIST(btf_bpf_link_id) +BTF_ID(struct, bpf_link) + +static const struct bpf_iter_seq_info bpf_link_seq_info = { + .seq_ops = &bpf_link_seq_ops, + .init_seq_private = NULL, + .fini_seq_private = NULL, + .seq_priv_size = sizeof(struct bpf_iter_seq_link_info), +}; + +static struct bpf_iter_reg bpf_link_reg_info = { + .target = "bpf_link", + .ctx_arg_info_size = 1, + .ctx_arg_info = { + { offsetof(struct bpf_iter__bpf_link, link), + PTR_TO_BTF_ID_OR_NULL }, + }, + .seq_info = &bpf_link_seq_info, +}; + +static int __init bpf_link_iter_init(void) +{ + bpf_link_reg_info.ctx_arg_info[0].btf_id = *btf_bpf_link_id; + return bpf_iter_reg_target(&bpf_link_reg_info); +} + +late_initcall(bpf_link_iter_init); diff --git a/kernel/bpf/ringbuf.c b/kernel/bpf/ringbuf.c index 311264ab80c4..ded4faeca192 100644 --- a/kernel/bpf/ringbuf.c +++ b/kernel/bpf/ringbuf.c @@ -475,3 +475,81 @@ const struct bpf_func_proto bpf_ringbuf_query_proto = { .arg1_type = ARG_CONST_MAP_PTR, .arg2_type = ARG_ANYTHING, }; + +BPF_CALL_4(bpf_ringbuf_reserve_dynptr, struct bpf_map *, map, u32, size, u64, flags, + struct bpf_dynptr_kern *, ptr) +{ + struct bpf_ringbuf_map *rb_map; + void *sample; + int err; + + if (unlikely(flags)) { + bpf_dynptr_set_null(ptr); + return -EINVAL; + } + + err = bpf_dynptr_check_size(size); + if (err) { + bpf_dynptr_set_null(ptr); + return err; + } + + rb_map = container_of(map, struct bpf_ringbuf_map, map); + + sample = __bpf_ringbuf_reserve(rb_map->rb, size); + if (!sample) { + bpf_dynptr_set_null(ptr); + return -EINVAL; + } + + bpf_dynptr_init(ptr, sample, BPF_DYNPTR_TYPE_RINGBUF, 0, size); + + return 0; +} + +const struct bpf_func_proto bpf_ringbuf_reserve_dynptr_proto = { + .func = bpf_ringbuf_reserve_dynptr, + .ret_type = RET_INTEGER, + .arg1_type = ARG_CONST_MAP_PTR, + .arg2_type = ARG_ANYTHING, + .arg3_type = ARG_ANYTHING, + .arg4_type = ARG_PTR_TO_DYNPTR | DYNPTR_TYPE_RINGBUF | MEM_UNINIT, +}; + +BPF_CALL_2(bpf_ringbuf_submit_dynptr, struct bpf_dynptr_kern *, ptr, u64, flags) +{ + if (!ptr->data) + return 0; + + bpf_ringbuf_commit(ptr->data, flags, false /* discard */); + + bpf_dynptr_set_null(ptr); + + return 0; +} + +const struct bpf_func_proto bpf_ringbuf_submit_dynptr_proto = { + .func = bpf_ringbuf_submit_dynptr, + .ret_type = RET_VOID, + .arg1_type = ARG_PTR_TO_DYNPTR | DYNPTR_TYPE_RINGBUF | OBJ_RELEASE, + .arg2_type = ARG_ANYTHING, +}; + +BPF_CALL_2(bpf_ringbuf_discard_dynptr, struct bpf_dynptr_kern *, ptr, u64, flags) +{ + if (!ptr->data) + return 0; + + bpf_ringbuf_commit(ptr->data, flags, true /* discard */); + + bpf_dynptr_set_null(ptr); + + return 0; +} + +const struct bpf_func_proto bpf_ringbuf_discard_dynptr_proto = { + .func = bpf_ringbuf_discard_dynptr, + .ret_type = RET_VOID, + .arg1_type = ARG_PTR_TO_DYNPTR | DYNPTR_TYPE_RINGBUF | OBJ_RELEASE, + .arg2_type = ARG_ANYTHING, +}; diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c index e0aead17dff4..2b69306d3c6e 100644 --- a/kernel/bpf/syscall.c +++ b/kernel/bpf/syscall.c @@ -2864,19 +2864,12 @@ struct bpf_link *bpf_link_get_from_fd(u32 ufd) } EXPORT_SYMBOL(bpf_link_get_from_fd); -struct bpf_tracing_link { - struct bpf_link link; - enum bpf_attach_type attach_type; - struct bpf_trampoline *trampoline; - struct bpf_prog *tgt_prog; -}; - static void bpf_tracing_link_release(struct bpf_link *link) { struct bpf_tracing_link *tr_link = - container_of(link, struct bpf_tracing_link, link); + container_of(link, struct bpf_tracing_link, link.link); - WARN_ON_ONCE(bpf_trampoline_unlink_prog(link->prog, + WARN_ON_ONCE(bpf_trampoline_unlink_prog(&tr_link->link, tr_link->trampoline)); bpf_trampoline_put(tr_link->trampoline); @@ -2889,7 +2882,7 @@ static void bpf_tracing_link_release(struct bpf_link *link) static void bpf_tracing_link_dealloc(struct bpf_link *link) { struct bpf_tracing_link *tr_link = - container_of(link, struct bpf_tracing_link, link); + container_of(link, struct bpf_tracing_link, link.link); kfree(tr_link); } @@ -2898,7 +2891,7 @@ static void bpf_tracing_link_show_fdinfo(const struct bpf_link *link, struct seq_file *seq) { struct bpf_tracing_link *tr_link = - container_of(link, struct bpf_tracing_link, link); + container_of(link, struct bpf_tracing_link, link.link); seq_printf(seq, "attach_type:\t%d\n", @@ -2909,7 +2902,7 @@ static int bpf_tracing_link_fill_link_info(const struct bpf_link *link, struct bpf_link_info *info) { struct bpf_tracing_link *tr_link = - container_of(link, struct bpf_tracing_link, link); + container_of(link, struct bpf_tracing_link, link.link); info->tracing.attach_type = tr_link->attach_type; bpf_trampoline_unpack_key(tr_link->trampoline->key, @@ -2928,7 +2921,8 @@ static const struct bpf_link_ops bpf_tracing_link_lops = { static int bpf_tracing_prog_attach(struct bpf_prog *prog, int tgt_prog_fd, - u32 btf_id) + u32 btf_id, + u64 bpf_cookie) { struct bpf_link_primer link_primer; struct bpf_prog *tgt_prog = NULL; @@ -2990,9 +2984,10 @@ static int bpf_tracing_prog_attach(struct bpf_prog *prog, err = -ENOMEM; goto out_put_prog; } - bpf_link_init(&link->link, BPF_LINK_TYPE_TRACING, + bpf_link_init(&link->link.link, BPF_LINK_TYPE_TRACING, &bpf_tracing_link_lops, prog); link->attach_type = prog->expected_attach_type; + link->link.cookie = bpf_cookie; mutex_lock(&prog->aux->dst_mutex); @@ -3060,11 +3055,11 @@ static int bpf_tracing_prog_attach(struct bpf_prog *prog, tgt_prog = prog->aux->dst_prog; } - err = bpf_link_prime(&link->link, &link_primer); + err = bpf_link_prime(&link->link.link, &link_primer); if (err) goto out_unlock; - err = bpf_trampoline_link_prog(prog, tr); + err = bpf_trampoline_link_prog(&link->link, tr); if (err) { bpf_link_cleanup(&link_primer); link = NULL; @@ -3278,7 +3273,7 @@ static int bpf_raw_tp_link_attach(struct bpf_prog *prog, tp_name = prog->aux->attach_func_name; break; } - return bpf_tracing_prog_attach(prog, 0, 0); + return bpf_tracing_prog_attach(prog, 0, 0, 0); case BPF_PROG_TYPE_RAW_TRACEPOINT: case BPF_PROG_TYPE_RAW_TRACEPOINT_WRITABLE: if (strncpy_from_user(buf, user_tp_name, sizeof(buf) - 1) < 0) @@ -4531,7 +4526,8 @@ static int link_create(union bpf_attr *attr, bpfptr_t uattr) case BPF_PROG_TYPE_EXT: ret = bpf_tracing_prog_attach(prog, attr->link_create.target_fd, - attr->link_create.target_btf_id); + attr->link_create.target_btf_id, + attr->link_create.tracing.cookie); break; case BPF_PROG_TYPE_LSM: case BPF_PROG_TYPE_TRACING: @@ -4546,7 +4542,8 @@ static int link_create(union bpf_attr *attr, bpfptr_t uattr) else ret = bpf_tracing_prog_attach(prog, attr->link_create.target_fd, - attr->link_create.target_btf_id); + attr->link_create.target_btf_id, + attr->link_create.tracing.cookie); break; case BPF_PROG_TYPE_FLOW_DISSECTOR: case BPF_PROG_TYPE_SK_LOOKUP: @@ -4680,6 +4677,25 @@ struct bpf_link *bpf_link_by_id(u32 id) return link; } +struct bpf_link *bpf_link_get_curr_or_next(u32 *id) +{ + struct bpf_link *link; + + spin_lock_bh(&link_idr_lock); +again: + link = idr_get_next(&link_idr, id); + if (link) { + link = bpf_link_inc_not_zero(link); + if (IS_ERR(link)) { + (*id)++; + goto again; + } + } + spin_unlock_bh(&link_idr_lock); + + return link; +} + #define BPF_LINK_GET_FD_BY_ID_LAST_FIELD link_id static int bpf_link_get_fd_by_id(const union bpf_attr *attr) @@ -4847,9 +4863,21 @@ out_prog_put: static int __sys_bpf(int cmd, bpfptr_t uattr, unsigned int size) { union bpf_attr attr; + bool capable; int err; - if (sysctl_unprivileged_bpf_disabled && !bpf_capable()) + capable = bpf_capable() || !sysctl_unprivileged_bpf_disabled; + + /* Intent here is for unprivileged_bpf_disabled to block key object + * creation commands for unprivileged users; other actions depend + * of fd availability and access to bpffs, so are dependent on + * object creation success. Capabilities are later verified for + * operations such as load and map create, so even with unprivileged + * BPF disabled, capability checks are still carried out for these + * and other operations. + */ + if (!capable && + (cmd == BPF_MAP_CREATE || cmd == BPF_PROG_LOAD)) return -EPERM; err = bpf_check_uarg_tail_zero(uattr, sizeof(attr), size); @@ -5008,6 +5036,7 @@ static bool syscall_prog_is_valid_access(int off, int size, BPF_CALL_3(bpf_sys_bpf, int, cmd, union bpf_attr *, attr, u32, attr_size) { struct bpf_prog * __maybe_unused prog; + struct bpf_tramp_run_ctx __maybe_unused run_ctx; switch (cmd) { case BPF_MAP_CREATE: @@ -5035,13 +5064,15 @@ BPF_CALL_3(bpf_sys_bpf, int, cmd, union bpf_attr *, attr, u32, attr_size) return -EINVAL; } - if (!__bpf_prog_enter_sleepable(prog)) { + run_ctx.bpf_cookie = 0; + run_ctx.saved_run_ctx = NULL; + if (!__bpf_prog_enter_sleepable(prog, &run_ctx)) { /* recursion detected */ bpf_prog_put(prog); return -EBUSY; } attr->test.retval = bpf_prog_run(prog, (void *) (long) attr->test.ctx_in); - __bpf_prog_exit_sleepable(prog, 0 /* bpf_prog_run does runtime stats */); + __bpf_prog_exit_sleepable(prog, 0 /* bpf_prog_run does runtime stats */, &run_ctx); bpf_prog_put(prog); return 0; #endif diff --git a/kernel/bpf/trampoline.c b/kernel/bpf/trampoline.c index ada97751ae1b..93c7675f0c9e 100644 --- a/kernel/bpf/trampoline.c +++ b/kernel/bpf/trampoline.c @@ -30,9 +30,12 @@ static DEFINE_MUTEX(trampoline_mutex); bool bpf_prog_has_trampoline(const struct bpf_prog *prog) { enum bpf_attach_type eatype = prog->expected_attach_type; + enum bpf_prog_type ptype = prog->type; - return eatype == BPF_TRACE_FENTRY || eatype == BPF_TRACE_FEXIT || - eatype == BPF_MODIFY_RETURN; + return (ptype == BPF_PROG_TYPE_TRACING && + (eatype == BPF_TRACE_FENTRY || eatype == BPF_TRACE_FEXIT || + eatype == BPF_MODIFY_RETURN)) || + (ptype == BPF_PROG_TYPE_LSM && eatype == BPF_LSM_MAC); } void *bpf_jit_alloc_exec_page(void) @@ -168,30 +171,30 @@ static int register_fentry(struct bpf_trampoline *tr, void *new_addr) return ret; } -static struct bpf_tramp_progs * +static struct bpf_tramp_links * bpf_trampoline_get_progs(const struct bpf_trampoline *tr, int *total, bool *ip_arg) { - const struct bpf_prog_aux *aux; - struct bpf_tramp_progs *tprogs; - struct bpf_prog **progs; + struct bpf_tramp_link *link; + struct bpf_tramp_links *tlinks; + struct bpf_tramp_link **links; int kind; *total = 0; - tprogs = kcalloc(BPF_TRAMP_MAX, sizeof(*tprogs), GFP_KERNEL); - if (!tprogs) + tlinks = kcalloc(BPF_TRAMP_MAX, sizeof(*tlinks), GFP_KERNEL); + if (!tlinks) return ERR_PTR(-ENOMEM); for (kind = 0; kind < BPF_TRAMP_MAX; kind++) { - tprogs[kind].nr_progs = tr->progs_cnt[kind]; + tlinks[kind].nr_links = tr->progs_cnt[kind]; *total += tr->progs_cnt[kind]; - progs = tprogs[kind].progs; + links = tlinks[kind].links; - hlist_for_each_entry(aux, &tr->progs_hlist[kind], tramp_hlist) { - *ip_arg |= aux->prog->call_get_func_ip; - *progs++ = aux->prog; + hlist_for_each_entry(link, &tr->progs_hlist[kind], tramp_hlist) { + *ip_arg |= link->link.prog->call_get_func_ip; + *links++ = link; } } - return tprogs; + return tlinks; } static void __bpf_tramp_image_put_deferred(struct work_struct *work) @@ -330,14 +333,14 @@ out: static int bpf_trampoline_update(struct bpf_trampoline *tr) { struct bpf_tramp_image *im; - struct bpf_tramp_progs *tprogs; + struct bpf_tramp_links *tlinks; u32 flags = BPF_TRAMP_F_RESTORE_REGS; bool ip_arg = false; int err, total; - tprogs = bpf_trampoline_get_progs(tr, &total, &ip_arg); - if (IS_ERR(tprogs)) - return PTR_ERR(tprogs); + tlinks = bpf_trampoline_get_progs(tr, &total, &ip_arg); + if (IS_ERR(tlinks)) + return PTR_ERR(tlinks); if (total == 0) { err = unregister_fentry(tr, tr->cur_image->image); @@ -353,15 +356,15 @@ static int bpf_trampoline_update(struct bpf_trampoline *tr) goto out; } - if (tprogs[BPF_TRAMP_FEXIT].nr_progs || - tprogs[BPF_TRAMP_MODIFY_RETURN].nr_progs) + if (tlinks[BPF_TRAMP_FEXIT].nr_links || + tlinks[BPF_TRAMP_MODIFY_RETURN].nr_links) flags = BPF_TRAMP_F_CALL_ORIG | BPF_TRAMP_F_SKIP_FRAME; if (ip_arg) flags |= BPF_TRAMP_F_IP_ARG; err = arch_prepare_bpf_trampoline(im, im->image, im->image + PAGE_SIZE, - &tr->func.model, flags, tprogs, + &tr->func.model, flags, tlinks, tr->func.addr); if (err < 0) goto out; @@ -381,7 +384,7 @@ static int bpf_trampoline_update(struct bpf_trampoline *tr) tr->cur_image = im; tr->selector++; out: - kfree(tprogs); + kfree(tlinks); return err; } @@ -407,13 +410,14 @@ static enum bpf_tramp_prog_type bpf_attach_type_to_tramp(struct bpf_prog *prog) } } -int bpf_trampoline_link_prog(struct bpf_prog *prog, struct bpf_trampoline *tr) +int bpf_trampoline_link_prog(struct bpf_tramp_link *link, struct bpf_trampoline *tr) { enum bpf_tramp_prog_type kind; + struct bpf_tramp_link *link_exiting; int err = 0; - int cnt; + int cnt = 0, i; - kind = bpf_attach_type_to_tramp(prog); + kind = bpf_attach_type_to_tramp(link->link.prog); mutex_lock(&tr->mutex); if (tr->extension_prog) { /* cannot attach fentry/fexit if extension prog is attached. @@ -422,32 +426,43 @@ int bpf_trampoline_link_prog(struct bpf_prog *prog, struct bpf_trampoline *tr) err = -EBUSY; goto out; } - cnt = tr->progs_cnt[BPF_TRAMP_FENTRY] + tr->progs_cnt[BPF_TRAMP_FEXIT]; + + for (i = 0; i < BPF_TRAMP_MAX; i++) + cnt += tr->progs_cnt[i]; + if (kind == BPF_TRAMP_REPLACE) { /* Cannot attach extension if fentry/fexit are in use. */ if (cnt) { err = -EBUSY; goto out; } - tr->extension_prog = prog; + tr->extension_prog = link->link.prog; err = bpf_arch_text_poke(tr->func.addr, BPF_MOD_JUMP, NULL, - prog->bpf_func); + link->link.prog->bpf_func); goto out; } - if (cnt >= BPF_MAX_TRAMP_PROGS) { + if (cnt >= BPF_MAX_TRAMP_LINKS) { err = -E2BIG; goto out; } - if (!hlist_unhashed(&prog->aux->tramp_hlist)) { + if (!hlist_unhashed(&link->tramp_hlist)) { + /* prog already linked */ + err = -EBUSY; + goto out; + } + hlist_for_each_entry(link_exiting, &tr->progs_hlist[kind], tramp_hlist) { + if (link_exiting->link.prog != link->link.prog) + continue; /* prog already linked */ err = -EBUSY; goto out; } - hlist_add_head(&prog->aux->tramp_hlist, &tr->progs_hlist[kind]); + + hlist_add_head(&link->tramp_hlist, &tr->progs_hlist[kind]); tr->progs_cnt[kind]++; err = bpf_trampoline_update(tr); if (err) { - hlist_del_init(&prog->aux->tramp_hlist); + hlist_del_init(&link->tramp_hlist); tr->progs_cnt[kind]--; } out: @@ -456,12 +471,12 @@ out: } /* bpf_trampoline_unlink_prog() should never fail. */ -int bpf_trampoline_unlink_prog(struct bpf_prog *prog, struct bpf_trampoline *tr) +int bpf_trampoline_unlink_prog(struct bpf_tramp_link *link, struct bpf_trampoline *tr) { enum bpf_tramp_prog_type kind; int err; - kind = bpf_attach_type_to_tramp(prog); + kind = bpf_attach_type_to_tramp(link->link.prog); mutex_lock(&tr->mutex); if (kind == BPF_TRAMP_REPLACE) { WARN_ON_ONCE(!tr->extension_prog); @@ -470,7 +485,7 @@ int bpf_trampoline_unlink_prog(struct bpf_prog *prog, struct bpf_trampoline *tr) tr->extension_prog = NULL; goto out; } - hlist_del_init(&prog->aux->tramp_hlist); + hlist_del_init(&link->tramp_hlist); tr->progs_cnt[kind]--; err = bpf_trampoline_update(tr); out: @@ -500,16 +515,19 @@ out: void bpf_trampoline_put(struct bpf_trampoline *tr) { + int i; + if (!tr) return; mutex_lock(&trampoline_mutex); if (!refcount_dec_and_test(&tr->refcnt)) goto out; WARN_ON_ONCE(mutex_is_locked(&tr->mutex)); - if (WARN_ON_ONCE(!hlist_empty(&tr->progs_hlist[BPF_TRAMP_FENTRY]))) - goto out; - if (WARN_ON_ONCE(!hlist_empty(&tr->progs_hlist[BPF_TRAMP_FEXIT]))) - goto out; + + for (i = 0; i < BPF_TRAMP_MAX; i++) + if (WARN_ON_ONCE(!hlist_empty(&tr->progs_hlist[i]))) + goto out; + /* This code will be executed even when the last bpf_tramp_image * is alive. All progs are detached from the trampoline and the * trampoline image is patched with jmp into epilogue to skip @@ -559,11 +577,14 @@ static void notrace inc_misses_counter(struct bpf_prog *prog) * [2..MAX_U64] - execute bpf prog and record execution time. * This is start time. */ -u64 notrace __bpf_prog_enter(struct bpf_prog *prog) +u64 notrace __bpf_prog_enter(struct bpf_prog *prog, struct bpf_tramp_run_ctx *run_ctx) __acquires(RCU) { rcu_read_lock(); migrate_disable(); + + run_ctx->saved_run_ctx = bpf_set_run_ctx(&run_ctx->run_ctx); + if (unlikely(__this_cpu_inc_return(*(prog->active)) != 1)) { inc_misses_counter(prog); return 0; @@ -593,29 +614,38 @@ static void notrace update_prog_stats(struct bpf_prog *prog, } } -void notrace __bpf_prog_exit(struct bpf_prog *prog, u64 start) +void notrace __bpf_prog_exit(struct bpf_prog *prog, u64 start, struct bpf_tramp_run_ctx *run_ctx) __releases(RCU) { + bpf_reset_run_ctx(run_ctx->saved_run_ctx); + update_prog_stats(prog, start); __this_cpu_dec(*(prog->active)); migrate_enable(); rcu_read_unlock(); } -u64 notrace __bpf_prog_enter_sleepable(struct bpf_prog *prog) +u64 notrace __bpf_prog_enter_sleepable(struct bpf_prog *prog, struct bpf_tramp_run_ctx *run_ctx) { rcu_read_lock_trace(); migrate_disable(); might_fault(); + if (unlikely(__this_cpu_inc_return(*(prog->active)) != 1)) { inc_misses_counter(prog); return 0; } + + run_ctx->saved_run_ctx = bpf_set_run_ctx(&run_ctx->run_ctx); + return bpf_prog_start_time(); } -void notrace __bpf_prog_exit_sleepable(struct bpf_prog *prog, u64 start) +void notrace __bpf_prog_exit_sleepable(struct bpf_prog *prog, u64 start, + struct bpf_tramp_run_ctx *run_ctx) { + bpf_reset_run_ctx(run_ctx->saved_run_ctx); + update_prog_stats(prog, start); __this_cpu_dec(*(prog->active)); migrate_enable(); @@ -635,7 +665,7 @@ void notrace __bpf_tramp_exit(struct bpf_tramp_image *tr) int __weak arch_prepare_bpf_trampoline(struct bpf_tramp_image *tr, void *image, void *image_end, const struct btf_func_model *m, u32 flags, - struct bpf_tramp_progs *tprogs, + struct bpf_tramp_links *tlinks, void *orig_call) { return -ENOTSUPP; diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c index 813f6ee80419..aedac2ac02b9 100644 --- a/kernel/bpf/verifier.c +++ b/kernel/bpf/verifier.c @@ -187,6 +187,9 @@ struct bpf_verifier_stack_elem { POISON_POINTER_DELTA)) #define BPF_MAP_PTR(X) ((struct bpf_map *)((X) & ~BPF_MAP_PTR_UNPRIV)) +static int acquire_reference_state(struct bpf_verifier_env *env, int insn_idx); +static int release_reference(struct bpf_verifier_env *env, int ref_obj_id); + static bool bpf_map_ptr_poisoned(const struct bpf_insn_aux_data *aux) { return BPF_MAP_PTR(aux->map_ptr_state) == BPF_MAP_PTR_POISON; @@ -259,6 +262,7 @@ struct bpf_call_arg_meta { u32 ret_btf_id; u32 subprogno; struct bpf_map_value_off_desc *kptr_off_desc; + u8 uninit_dynptr_regno; }; struct btf *btf_vmlinux; @@ -509,6 +513,7 @@ static bool is_ptr_cast_function(enum bpf_func_id func_id) func_id == BPF_FUNC_skc_to_tcp_sock || func_id == BPF_FUNC_skc_to_tcp6_sock || func_id == BPF_FUNC_skc_to_udp6_sock || + func_id == BPF_FUNC_skc_to_mptcp_sock || func_id == BPF_FUNC_skc_to_tcp_timewait_sock || func_id == BPF_FUNC_skc_to_tcp_request_sock; } @@ -580,6 +585,7 @@ static char slot_type_char[] = { [STACK_SPILL] = 'r', [STACK_MISC] = 'm', [STACK_ZERO] = '0', + [STACK_DYNPTR] = 'd', }; static void print_liveness(struct bpf_verifier_env *env, @@ -595,6 +601,25 @@ static void print_liveness(struct bpf_verifier_env *env, verbose(env, "D"); } +static int get_spi(s32 off) +{ + return (-off - 1) / BPF_REG_SIZE; +} + +static bool is_spi_bounds_valid(struct bpf_func_state *state, int spi, int nr_slots) +{ + int allocated_slots = state->allocated_stack / BPF_REG_SIZE; + + /* We need to check that slots between [spi - nr_slots + 1, spi] are + * within [0, allocated_stack). + * + * Please note that the spi grows downwards. For example, a dynptr + * takes the size of two stack slots; the first slot will be at + * spi and the second slot will be at spi - 1. + */ + return spi - nr_slots + 1 >= 0 && spi < allocated_slots; +} + static struct bpf_func_state *func(struct bpf_verifier_env *env, const struct bpf_reg_state *reg) { @@ -646,6 +671,132 @@ static void mark_verifier_state_scratched(struct bpf_verifier_env *env) env->scratched_stack_slots = ~0ULL; } +static enum bpf_dynptr_type arg_to_dynptr_type(enum bpf_arg_type arg_type) +{ + switch (arg_type & DYNPTR_TYPE_FLAG_MASK) { + case DYNPTR_TYPE_LOCAL: + return BPF_DYNPTR_TYPE_LOCAL; + case DYNPTR_TYPE_RINGBUF: + return BPF_DYNPTR_TYPE_RINGBUF; + default: + return BPF_DYNPTR_TYPE_INVALID; + } +} + +static bool dynptr_type_refcounted(enum bpf_dynptr_type type) +{ + return type == BPF_DYNPTR_TYPE_RINGBUF; +} + +static int mark_stack_slots_dynptr(struct bpf_verifier_env *env, struct bpf_reg_state *reg, + enum bpf_arg_type arg_type, int insn_idx) +{ + struct bpf_func_state *state = func(env, reg); + enum bpf_dynptr_type type; + int spi, i, id; + + spi = get_spi(reg->off); + + if (!is_spi_bounds_valid(state, spi, BPF_DYNPTR_NR_SLOTS)) + return -EINVAL; + + for (i = 0; i < BPF_REG_SIZE; i++) { + state->stack[spi].slot_type[i] = STACK_DYNPTR; + state->stack[spi - 1].slot_type[i] = STACK_DYNPTR; + } + + type = arg_to_dynptr_type(arg_type); + if (type == BPF_DYNPTR_TYPE_INVALID) + return -EINVAL; + + state->stack[spi].spilled_ptr.dynptr.first_slot = true; + state->stack[spi].spilled_ptr.dynptr.type = type; + state->stack[spi - 1].spilled_ptr.dynptr.type = type; + + if (dynptr_type_refcounted(type)) { + /* The id is used to track proper releasing */ + id = acquire_reference_state(env, insn_idx); + if (id < 0) + return id; + + state->stack[spi].spilled_ptr.id = id; + state->stack[spi - 1].spilled_ptr.id = id; + } + + return 0; +} + +static int unmark_stack_slots_dynptr(struct bpf_verifier_env *env, struct bpf_reg_state *reg) +{ + struct bpf_func_state *state = func(env, reg); + int spi, i; + + spi = get_spi(reg->off); + + if (!is_spi_bounds_valid(state, spi, BPF_DYNPTR_NR_SLOTS)) + return -EINVAL; + + for (i = 0; i < BPF_REG_SIZE; i++) { + state->stack[spi].slot_type[i] = STACK_INVALID; + state->stack[spi - 1].slot_type[i] = STACK_INVALID; + } + + /* Invalidate any slices associated with this dynptr */ + if (dynptr_type_refcounted(state->stack[spi].spilled_ptr.dynptr.type)) { + release_reference(env, state->stack[spi].spilled_ptr.id); + state->stack[spi].spilled_ptr.id = 0; + state->stack[spi - 1].spilled_ptr.id = 0; + } + + state->stack[spi].spilled_ptr.dynptr.first_slot = false; + state->stack[spi].spilled_ptr.dynptr.type = 0; + state->stack[spi - 1].spilled_ptr.dynptr.type = 0; + + return 0; +} + +static bool is_dynptr_reg_valid_uninit(struct bpf_verifier_env *env, struct bpf_reg_state *reg) +{ + struct bpf_func_state *state = func(env, reg); + int spi = get_spi(reg->off); + int i; + + if (!is_spi_bounds_valid(state, spi, BPF_DYNPTR_NR_SLOTS)) + return true; + + for (i = 0; i < BPF_REG_SIZE; i++) { + if (state->stack[spi].slot_type[i] == STACK_DYNPTR || + state->stack[spi - 1].slot_type[i] == STACK_DYNPTR) + return false; + } + + return true; +} + +static bool is_dynptr_reg_valid_init(struct bpf_verifier_env *env, struct bpf_reg_state *reg, + enum bpf_arg_type arg_type) +{ + struct bpf_func_state *state = func(env, reg); + int spi = get_spi(reg->off); + int i; + + if (!is_spi_bounds_valid(state, spi, BPF_DYNPTR_NR_SLOTS) || + !state->stack[spi].spilled_ptr.dynptr.first_slot) + return false; + + for (i = 0; i < BPF_REG_SIZE; i++) { + if (state->stack[spi].slot_type[i] != STACK_DYNPTR || + state->stack[spi - 1].slot_type[i] != STACK_DYNPTR) + return false; + } + + /* ARG_PTR_TO_DYNPTR takes any type of dynptr */ + if (arg_type == ARG_PTR_TO_DYNPTR) + return true; + + return state->stack[spi].spilled_ptr.dynptr.type == arg_to_dynptr_type(arg_type); +} + /* The reg state of a pointer or a bounded scalar was saved when * it was spilled to the stack. */ @@ -1815,8 +1966,7 @@ void bpf_free_kfunc_btf_tab(struct bpf_kfunc_btf_tab *tab) kfree(tab); } -static struct btf *find_kfunc_desc_btf(struct bpf_verifier_env *env, - u32 func_id, s16 offset) +static struct btf *find_kfunc_desc_btf(struct bpf_verifier_env *env, s16 offset) { if (offset) { if (offset < 0) { @@ -1891,7 +2041,7 @@ static int add_kfunc_call(struct bpf_verifier_env *env, u32 func_id, s16 offset) prog_aux->kfunc_btf_tab = btf_tab; } - desc_btf = find_kfunc_desc_btf(env, func_id, offset); + desc_btf = find_kfunc_desc_btf(env, offset); if (IS_ERR(desc_btf)) { verbose(env, "failed to find BTF for kernel function\n"); return PTR_ERR(desc_btf); @@ -2360,7 +2510,7 @@ static const char *disasm_kfunc_name(void *data, const struct bpf_insn *insn) if (insn->src_reg != BPF_PSEUDO_KFUNC_CALL) return NULL; - desc_btf = find_kfunc_desc_btf(data, insn->imm, insn->off); + desc_btf = find_kfunc_desc_btf(data, insn->off); if (IS_ERR(desc_btf)) return "<error>"; @@ -5352,7 +5502,7 @@ static int process_kptr_func(struct bpf_verifier_env *env, int regno, return -EINVAL; } if (!map_value_has_kptrs(map_ptr)) { - ret = PTR_ERR(map_ptr->kptr_off_tab); + ret = PTR_ERR_OR_ZERO(map_ptr->kptr_off_tab); if (ret == -E2BIG) verbose(env, "map '%s' has more than %d kptr\n", map_ptr->name, BPF_MAP_VALUE_OFF_MAX); @@ -5378,12 +5528,6 @@ static int process_kptr_func(struct bpf_verifier_env *env, int regno, return 0; } -static bool arg_type_is_mem_ptr(enum bpf_arg_type type) -{ - return base_type(type) == ARG_PTR_TO_MEM || - base_type(type) == ARG_PTR_TO_UNINIT_MEM; -} - static bool arg_type_is_mem_size(enum bpf_arg_type type) { return type == ARG_CONST_SIZE || @@ -5406,6 +5550,11 @@ static bool arg_type_is_release(enum bpf_arg_type type) return type & OBJ_RELEASE; } +static bool arg_type_is_dynptr(enum bpf_arg_type type) +{ + return base_type(type) == ARG_PTR_TO_DYNPTR; +} + static int int_ptr_type_to_size(enum bpf_arg_type type) { if (type == ARG_PTR_TO_INT) @@ -5523,7 +5672,6 @@ static const struct bpf_reg_types kptr_types = { .types = { PTR_TO_MAP_VALUE } } static const struct bpf_reg_types *compatible_reg_types[__BPF_ARG_TYPE_MAX] = { [ARG_PTR_TO_MAP_KEY] = &map_key_value_types, [ARG_PTR_TO_MAP_VALUE] = &map_key_value_types, - [ARG_PTR_TO_UNINIT_MAP_VALUE] = &map_key_value_types, [ARG_CONST_SIZE] = &scalar_types, [ARG_CONST_SIZE_OR_ZERO] = &scalar_types, [ARG_CONST_ALLOC_SIZE_OR_ZERO] = &scalar_types, @@ -5537,7 +5685,6 @@ static const struct bpf_reg_types *compatible_reg_types[__BPF_ARG_TYPE_MAX] = { [ARG_PTR_TO_BTF_ID] = &btf_ptr_types, [ARG_PTR_TO_SPIN_LOCK] = &spin_lock_types, [ARG_PTR_TO_MEM] = &mem_types, - [ARG_PTR_TO_UNINIT_MEM] = &mem_types, [ARG_PTR_TO_ALLOC_MEM] = &alloc_mem_types, [ARG_PTR_TO_INT] = &int_ptr_types, [ARG_PTR_TO_LONG] = &int_ptr_types, @@ -5547,6 +5694,7 @@ static const struct bpf_reg_types *compatible_reg_types[__BPF_ARG_TYPE_MAX] = { [ARG_PTR_TO_CONST_STR] = &const_str_ptr_types, [ARG_PTR_TO_TIMER] = &timer_types, [ARG_PTR_TO_KPTR] = &kptr_types, + [ARG_PTR_TO_DYNPTR] = &stack_ptr_types, }; static int check_reg_type(struct bpf_verifier_env *env, u32 regno, @@ -5636,8 +5784,13 @@ int check_func_arg_reg_off(struct bpf_verifier_env *env, bool fixed_off_ok = false; switch ((u32)type) { - case SCALAR_VALUE: /* Pointer types where reg offset is explicitly allowed: */ + case PTR_TO_STACK: + if (arg_type_is_dynptr(arg_type) && reg->off % BPF_REG_SIZE) { + verbose(env, "cannot pass in dynptr at an offset\n"); + return -EINVAL; + } + fallthrough; case PTR_TO_PACKET: case PTR_TO_PACKET_META: case PTR_TO_MAP_KEY: @@ -5647,7 +5800,7 @@ int check_func_arg_reg_off(struct bpf_verifier_env *env, case PTR_TO_MEM | MEM_ALLOC: case PTR_TO_BUF: case PTR_TO_BUF | MEM_RDONLY: - case PTR_TO_STACK: + case SCALAR_VALUE: /* Some of the argument types nevertheless require a * zero register offset. */ @@ -5679,6 +5832,14 @@ int check_func_arg_reg_off(struct bpf_verifier_env *env, return __check_ptr_off_reg(env, reg, regno, fixed_off_ok); } +static u32 stack_slot_get_id(struct bpf_verifier_env *env, struct bpf_reg_state *reg) +{ + struct bpf_func_state *state = func(env, reg); + int spi = get_spi(reg->off); + + return state->stack[spi].spilled_ptr.id; +} + static int check_func_arg(struct bpf_verifier_env *env, u32 arg, struct bpf_call_arg_meta *meta, const struct bpf_func_proto *fn) @@ -5711,8 +5872,7 @@ static int check_func_arg(struct bpf_verifier_env *env, u32 arg, return -EACCES; } - if (base_type(arg_type) == ARG_PTR_TO_MAP_VALUE || - base_type(arg_type) == ARG_PTR_TO_UNINIT_MAP_VALUE) { + if (base_type(arg_type) == ARG_PTR_TO_MAP_VALUE) { err = resolve_map_arg_type(env, meta, &arg_type); if (err) return err; @@ -5734,7 +5894,16 @@ static int check_func_arg(struct bpf_verifier_env *env, u32 arg, skip_type_check: if (arg_type_is_release(arg_type)) { - if (!reg->ref_obj_id && !register_is_null(reg)) { + if (arg_type_is_dynptr(arg_type)) { + struct bpf_func_state *state = func(env, reg); + int spi = get_spi(reg->off); + + if (!is_spi_bounds_valid(state, spi, BPF_DYNPTR_NR_SLOTS) || + !state->stack[spi].spilled_ptr.id) { + verbose(env, "arg %d is an unacquired reference\n", regno); + return -EINVAL; + } + } else if (!reg->ref_obj_id && !register_is_null(reg)) { verbose(env, "R%d must be referenced when passed to release function\n", regno); return -EINVAL; @@ -5798,8 +5967,7 @@ skip_type_check: err = check_helper_mem_access(env, regno, meta->map_ptr->key_size, false, NULL); - } else if (base_type(arg_type) == ARG_PTR_TO_MAP_VALUE || - base_type(arg_type) == ARG_PTR_TO_UNINIT_MAP_VALUE) { + } else if (base_type(arg_type) == ARG_PTR_TO_MAP_VALUE) { if (type_may_be_null(arg_type) && register_is_null(reg)) return 0; @@ -5811,7 +5979,7 @@ skip_type_check: verbose(env, "invalid map_ptr to access map->value\n"); return -EACCES; } - meta->raw_mode = (arg_type == ARG_PTR_TO_UNINIT_MAP_VALUE); + meta->raw_mode = arg_type & MEM_UNINIT; err = check_helper_mem_access(env, regno, meta->map_ptr->value_size, false, meta); @@ -5838,15 +6006,49 @@ skip_type_check: return -EACCES; } else if (arg_type == ARG_PTR_TO_FUNC) { meta->subprogno = reg->subprogno; - } else if (arg_type_is_mem_ptr(arg_type)) { + } else if (base_type(arg_type) == ARG_PTR_TO_MEM) { /* The access to this pointer is only checked when we hit the * next is_mem_size argument below. */ - meta->raw_mode = (arg_type == ARG_PTR_TO_UNINIT_MEM); + meta->raw_mode = arg_type & MEM_UNINIT; } else if (arg_type_is_mem_size(arg_type)) { bool zero_size_allowed = (arg_type == ARG_CONST_SIZE_OR_ZERO); err = check_mem_size_reg(env, reg, regno, zero_size_allowed, meta); + } else if (arg_type_is_dynptr(arg_type)) { + if (arg_type & MEM_UNINIT) { + if (!is_dynptr_reg_valid_uninit(env, reg)) { + verbose(env, "Dynptr has to be an uninitialized dynptr\n"); + return -EINVAL; + } + + /* We only support one dynptr being uninitialized at the moment, + * which is sufficient for the helper functions we have right now. + */ + if (meta->uninit_dynptr_regno) { + verbose(env, "verifier internal error: multiple uninitialized dynptr args\n"); + return -EFAULT; + } + + meta->uninit_dynptr_regno = regno; + } else if (!is_dynptr_reg_valid_init(env, reg, arg_type)) { + const char *err_extra = ""; + + switch (arg_type & DYNPTR_TYPE_FLAG_MASK) { + case DYNPTR_TYPE_LOCAL: + err_extra = "local "; + break; + case DYNPTR_TYPE_RINGBUF: + err_extra = "ringbuf "; + break; + default: + break; + } + + verbose(env, "Expected an initialized %sdynptr as arg #%d\n", + err_extra, arg + 1); + return -EINVAL; + } } else if (arg_type_is_alloc_size(arg_type)) { if (!tnum_is_const(reg->var_off)) { verbose(env, "R%d is not a known constant'\n", @@ -5968,7 +6170,10 @@ static int check_map_func_compatibility(struct bpf_verifier_env *env, case BPF_MAP_TYPE_RINGBUF: if (func_id != BPF_FUNC_ringbuf_output && func_id != BPF_FUNC_ringbuf_reserve && - func_id != BPF_FUNC_ringbuf_query) + func_id != BPF_FUNC_ringbuf_query && + func_id != BPF_FUNC_ringbuf_reserve_dynptr && + func_id != BPF_FUNC_ringbuf_submit_dynptr && + func_id != BPF_FUNC_ringbuf_discard_dynptr) goto error; break; case BPF_MAP_TYPE_STACK_TRACE: @@ -6084,6 +6289,9 @@ static int check_map_func_compatibility(struct bpf_verifier_env *env, case BPF_FUNC_ringbuf_output: case BPF_FUNC_ringbuf_reserve: case BPF_FUNC_ringbuf_query: + case BPF_FUNC_ringbuf_reserve_dynptr: + case BPF_FUNC_ringbuf_submit_dynptr: + case BPF_FUNC_ringbuf_discard_dynptr: if (map->map_type != BPF_MAP_TYPE_RINGBUF) goto error; break; @@ -6138,6 +6346,12 @@ static int check_map_func_compatibility(struct bpf_verifier_env *env, map->map_type != BPF_MAP_TYPE_BLOOM_FILTER) goto error; break; + case BPF_FUNC_map_lookup_percpu_elem: + if (map->map_type != BPF_MAP_TYPE_PERCPU_ARRAY && + map->map_type != BPF_MAP_TYPE_PERCPU_HASH && + map->map_type != BPF_MAP_TYPE_LRU_PERCPU_HASH) + goto error; + break; case BPF_FUNC_sk_storage_get: case BPF_FUNC_sk_storage_delete: if (map->map_type != BPF_MAP_TYPE_SK_STORAGE) @@ -6189,10 +6403,8 @@ static bool check_raw_mode_ok(const struct bpf_func_proto *fn) static bool check_args_pair_invalid(enum bpf_arg_type arg_curr, enum bpf_arg_type arg_next) { - return (arg_type_is_mem_ptr(arg_curr) && - !arg_type_is_mem_size(arg_next)) || - (!arg_type_is_mem_ptr(arg_curr) && - arg_type_is_mem_size(arg_next)); + return (base_type(arg_curr) == ARG_PTR_TO_MEM) != + arg_type_is_mem_size(arg_next); } static bool check_arg_pair_ok(const struct bpf_func_proto *fn) @@ -6203,7 +6415,7 @@ static bool check_arg_pair_ok(const struct bpf_func_proto *fn) * helper function specification. */ if (arg_type_is_mem_size(fn->arg1_type) || - arg_type_is_mem_ptr(fn->arg5_type) || + base_type(fn->arg5_type) == ARG_PTR_TO_MEM || check_args_pair_invalid(fn->arg1_type, fn->arg2_type) || check_args_pair_invalid(fn->arg2_type, fn->arg3_type) || check_args_pair_invalid(fn->arg3_type, fn->arg4_type) || @@ -6751,7 +6963,8 @@ record_func_map(struct bpf_verifier_env *env, struct bpf_call_arg_meta *meta, func_id != BPF_FUNC_map_pop_elem && func_id != BPF_FUNC_map_peek_elem && func_id != BPF_FUNC_for_each_map_elem && - func_id != BPF_FUNC_redirect_map) + func_id != BPF_FUNC_redirect_map && + func_id != BPF_FUNC_map_lookup_percpu_elem) return 0; if (map == NULL) { @@ -6975,9 +7188,27 @@ static int check_helper_call(struct bpf_verifier_env *env, struct bpf_insn *insn regs = cur_regs(env); + if (meta.uninit_dynptr_regno) { + /* we write BPF_DW bits (8 bytes) at a time */ + for (i = 0; i < BPF_DYNPTR_SIZE; i += 8) { + err = check_mem_access(env, insn_idx, meta.uninit_dynptr_regno, + i, BPF_DW, BPF_WRITE, -1, false); + if (err) + return err; + } + + err = mark_stack_slots_dynptr(env, ®s[meta.uninit_dynptr_regno], + fn->arg_type[meta.uninit_dynptr_regno - BPF_REG_1], + insn_idx); + if (err) + return err; + } + if (meta.release_regno) { err = -EINVAL; - if (meta.ref_obj_id) + if (arg_type_is_dynptr(fn->arg_type[meta.release_regno - BPF_REG_1])) + err = unmark_stack_slots_dynptr(env, ®s[meta.release_regno]); + else if (meta.ref_obj_id) err = release_reference(env, meta.ref_obj_id); /* meta.ref_obj_id can only be 0 if register that is meant to be * released is NULL, which must be > R0. @@ -7027,6 +7258,12 @@ static int check_helper_call(struct bpf_verifier_env *env, struct bpf_insn *insn err = __check_func_call(env, insn, insn_idx_p, meta.subprogno, set_loop_callback_state); break; + case BPF_FUNC_dynptr_from_mem: + if (regs[BPF_REG_1].type != PTR_TO_MAP_VALUE) { + verbose(env, "Unsupported reg type %s for bpf_dynptr_from_mem data\n", + reg_type_str(env, regs[BPF_REG_1].type)); + return -EACCES; + } } if (err) @@ -7155,6 +7392,21 @@ static int check_helper_call(struct bpf_verifier_env *env, struct bpf_insn *insn regs[BPF_REG_0].id = id; /* For release_reference() */ regs[BPF_REG_0].ref_obj_id = id; + } else if (func_id == BPF_FUNC_dynptr_data) { + int dynptr_id = 0, i; + + /* Find the id of the dynptr we're acquiring a reference to */ + for (i = 0; i < MAX_BPF_FUNC_REG_ARGS; i++) { + if (arg_type_is_dynptr(fn->arg_type[i])) { + if (dynptr_id) { + verbose(env, "verifier internal error: multiple dynptr args in func\n"); + return -EFAULT; + } + dynptr_id = stack_slot_get_id(env, ®s[BPF_REG_1 + i]); + } + } + /* For release_reference() */ + regs[BPF_REG_0].ref_obj_id = dynptr_id; } do_refine_retval_range(regs, fn->ret_type, func_id, &meta); @@ -7237,7 +7489,7 @@ static int check_kfunc_call(struct bpf_verifier_env *env, struct bpf_insn *insn, if (!insn->imm) return 0; - desc_btf = find_kfunc_desc_btf(env, insn->imm, insn->off); + desc_btf = find_kfunc_desc_btf(env, insn->off); if (IS_ERR(desc_btf)) return PTR_ERR(desc_btf); @@ -13811,7 +14063,8 @@ static int do_misc_fixups(struct bpf_verifier_env *env) insn->imm == BPF_FUNC_map_pop_elem || insn->imm == BPF_FUNC_map_peek_elem || insn->imm == BPF_FUNC_redirect_map || - insn->imm == BPF_FUNC_for_each_map_elem)) { + insn->imm == BPF_FUNC_for_each_map_elem || + insn->imm == BPF_FUNC_map_lookup_percpu_elem)) { aux = &env->insn_aux_data[i + delta]; if (bpf_map_ptr_poisoned(aux)) goto patch_call_imm; @@ -13860,6 +14113,8 @@ static int do_misc_fixups(struct bpf_verifier_env *env) bpf_callback_t callback_fn, void *callback_ctx, u64 flags))NULL)); + BUILD_BUG_ON(!__same_type(ops->map_lookup_percpu_elem, + (void *(*)(struct bpf_map *map, void *key, u32 cpu))NULL)); patch_map_ops_generic: switch (insn->imm) { @@ -13887,6 +14142,9 @@ patch_map_ops_generic: case BPF_FUNC_for_each_map_elem: insn->imm = BPF_CALL_IMM(ops->map_for_each_callback); continue; + case BPF_FUNC_map_lookup_percpu_elem: + insn->imm = BPF_CALL_IMM(ops->map_lookup_percpu_elem); + continue; } goto patch_call_imm; diff --git a/kernel/kallsyms.c b/kernel/kallsyms.c index 79f2eb617a62..fbdf8d3279ac 100644 --- a/kernel/kallsyms.c +++ b/kernel/kallsyms.c @@ -29,6 +29,7 @@ #include <linux/compiler.h> #include <linux/module.h> #include <linux/kernel.h> +#include <linux/bsearch.h> /* * These will be re-linked against their real values @@ -228,7 +229,6 @@ unsigned long kallsyms_lookup_name(const char *name) return module_kallsyms_lookup_name(name); } -#ifdef CONFIG_LIVEPATCH /* * Iterate over all symbols in vmlinux. For symbols from modules use * module_kallsyms_on_each_symbol instead. @@ -251,7 +251,6 @@ int kallsyms_on_each_symbol(int (*fn)(void *, const char *, struct module *, } return 0; } -#endif /* CONFIG_LIVEPATCH */ static unsigned long get_symbol_pos(unsigned long addr, unsigned long *symbolsize, diff --git a/kernel/trace/bpf_trace.c b/kernel/trace/bpf_trace.c index f15b826f9899..10b157a6d73e 100644 --- a/kernel/trace/bpf_trace.c +++ b/kernel/trace/bpf_trace.c @@ -1091,6 +1091,21 @@ static const struct bpf_func_proto bpf_get_attach_cookie_proto_pe = { .arg1_type = ARG_PTR_TO_CTX, }; +BPF_CALL_1(bpf_get_attach_cookie_tracing, void *, ctx) +{ + struct bpf_trace_run_ctx *run_ctx; + + run_ctx = container_of(current->bpf_ctx, struct bpf_trace_run_ctx, run_ctx); + return run_ctx->bpf_cookie; +} + +static const struct bpf_func_proto bpf_get_attach_cookie_proto_tracing = { + .func = bpf_get_attach_cookie_tracing, + .gpl_only = false, + .ret_type = RET_INTEGER, + .arg1_type = ARG_PTR_TO_CTX, +}; + BPF_CALL_3(bpf_get_branch_snapshot, void *, buf, u32, size, u64, flags) { #ifndef CONFIG_X86 @@ -1182,6 +1197,8 @@ bpf_tracing_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) return &bpf_map_pop_elem_proto; case BPF_FUNC_map_peek_elem: return &bpf_map_peek_elem_proto; + case BPF_FUNC_map_lookup_percpu_elem: + return &bpf_map_lookup_percpu_elem_proto; case BPF_FUNC_ktime_get_ns: return &bpf_ktime_get_ns_proto; case BPF_FUNC_ktime_get_boot_ns: @@ -1688,6 +1705,8 @@ tracing_prog_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) return &bpf_skc_to_udp6_sock_proto; case BPF_FUNC_skc_to_unix_sock: return &bpf_skc_to_unix_sock_proto; + case BPF_FUNC_skc_to_mptcp_sock: + return &bpf_skc_to_mptcp_sock_proto; case BPF_FUNC_sk_storage_get: return &bpf_sk_storage_get_tracing_proto; case BPF_FUNC_sk_storage_delete: @@ -1719,6 +1738,8 @@ tracing_prog_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) return bpf_prog_has_trampoline(prog) ? &bpf_get_func_ret_proto : NULL; case BPF_FUNC_get_func_arg_cnt: return bpf_prog_has_trampoline(prog) ? &bpf_get_func_arg_cnt_proto : NULL; + case BPF_FUNC_get_attach_cookie: + return bpf_prog_has_trampoline(prog) ? &bpf_get_attach_cookie_proto_tracing : NULL; default: fn = raw_tp_prog_func_proto(func_id, prog); if (!fn && prog->expected_attach_type == BPF_TRACE_ITER) @@ -2229,6 +2250,59 @@ struct bpf_kprobe_multi_run_ctx { unsigned long entry_ip; }; +struct user_syms { + const char **syms; + char *buf; +}; + +static int copy_user_syms(struct user_syms *us, unsigned long __user *usyms, u32 cnt) +{ + unsigned long __user usymbol; + const char **syms = NULL; + char *buf = NULL, *p; + int err = -ENOMEM; + unsigned int i; + + syms = kvmalloc(cnt * sizeof(*syms), GFP_KERNEL); + if (!syms) + goto error; + + buf = kvmalloc(cnt * KSYM_NAME_LEN, GFP_KERNEL); + if (!buf) + goto error; + + for (p = buf, i = 0; i < cnt; i++) { + if (__get_user(usymbol, usyms + i)) { + err = -EFAULT; + goto error; + } + err = strncpy_from_user(p, (const char __user *) usymbol, KSYM_NAME_LEN); + if (err == KSYM_NAME_LEN) + err = -E2BIG; + if (err < 0) + goto error; + syms[i] = p; + p += err + 1; + } + + us->syms = syms; + us->buf = buf; + return 0; + +error: + if (err) { + kvfree(syms); + kvfree(buf); + } + return err; +} + +static void free_user_syms(struct user_syms *us) +{ + kvfree(us->syms); + kvfree(us->buf); +} + static void bpf_kprobe_multi_link_release(struct bpf_link *link) { struct bpf_kprobe_multi_link *kmulti_link; @@ -2349,53 +2423,12 @@ kprobe_multi_link_handler(struct fprobe *fp, unsigned long entry_ip, kprobe_multi_link_prog_run(link, entry_ip, regs); } -static int -kprobe_multi_resolve_syms(const void __user *usyms, u32 cnt, - unsigned long *addrs) +static int symbols_cmp(const void *a, const void *b) { - unsigned long addr, size; - const char __user **syms; - int err = -ENOMEM; - unsigned int i; - char *func; - - size = cnt * sizeof(*syms); - syms = kvzalloc(size, GFP_KERNEL); - if (!syms) - return -ENOMEM; + const char **str_a = (const char **) a; + const char **str_b = (const char **) b; - func = kmalloc(KSYM_NAME_LEN, GFP_KERNEL); - if (!func) - goto error; - - if (copy_from_user(syms, usyms, size)) { - err = -EFAULT; - goto error; - } - - for (i = 0; i < cnt; i++) { - err = strncpy_from_user(func, syms[i], KSYM_NAME_LEN); - if (err == KSYM_NAME_LEN) - err = -E2BIG; - if (err < 0) - goto error; - err = -EINVAL; - addr = kallsyms_lookup_name(func); - if (!addr) - goto error; - if (!kallsyms_lookup_size_offset(addr, &size, NULL)) - goto error; - addr = ftrace_location_range(addr, addr + size - 1); - if (!addr) - goto error; - addrs[i] = addr; - } - - err = 0; -error: - kvfree(syms); - kfree(func); - return err; + return strcmp(*str_a, *str_b); } int bpf_kprobe_multi_link_attach(const union bpf_attr *attr, struct bpf_prog *prog) @@ -2441,7 +2474,15 @@ int bpf_kprobe_multi_link_attach(const union bpf_attr *attr, struct bpf_prog *pr goto error; } } else { - err = kprobe_multi_resolve_syms(usyms, cnt, addrs); + struct user_syms us; + + err = copy_user_syms(&us, usyms, cnt); + if (err) + goto error; + + sort(us.syms, cnt, sizeof(*us.syms), symbols_cmp, NULL); + err = ftrace_lookup_symbols(us.syms, cnt, addrs); + free_user_syms(&us); if (err) goto error; } diff --git a/kernel/trace/fprobe.c b/kernel/trace/fprobe.c index 89d9f994ebb0..aac63ca9c3d1 100644 --- a/kernel/trace/fprobe.c +++ b/kernel/trace/fprobe.c @@ -85,39 +85,31 @@ static void fprobe_exit_handler(struct rethook_node *rh, void *data, } NOKPROBE_SYMBOL(fprobe_exit_handler); +static int symbols_cmp(const void *a, const void *b) +{ + const char **str_a = (const char **) a; + const char **str_b = (const char **) b; + + return strcmp(*str_a, *str_b); +} + /* Convert ftrace location address from symbols */ static unsigned long *get_ftrace_locations(const char **syms, int num) { - unsigned long addr, size; unsigned long *addrs; - int i; /* Convert symbols to symbol address */ addrs = kcalloc(num, sizeof(*addrs), GFP_KERNEL); if (!addrs) return ERR_PTR(-ENOMEM); - for (i = 0; i < num; i++) { - addr = kallsyms_lookup_name(syms[i]); - if (!addr) /* Maybe wrong symbol */ - goto error; - - /* Convert symbol address to ftrace location. */ - if (!kallsyms_lookup_size_offset(addr, &size, NULL) || !size) - goto error; + /* ftrace_lookup_symbols expects sorted symbols */ + sort(syms, num, sizeof(*syms), symbols_cmp, NULL); - addr = ftrace_location_range(addr, addr + size - 1); - if (!addr) /* No dynamic ftrace there. */ - goto error; + if (!ftrace_lookup_symbols(syms, num, addrs)) + return addrs; - addrs[i] = addr; - } - - return addrs; - -error: kfree(addrs); - return ERR_PTR(-ENOENT); } diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c index af899b058c8d..674add0aafb3 100644 --- a/kernel/trace/ftrace.c +++ b/kernel/trace/ftrace.c @@ -7964,3 +7964,65 @@ ftrace_enable_sysctl(struct ctl_table *table, int write, mutex_unlock(&ftrace_lock); return ret; } + +static int symbols_cmp(const void *a, const void *b) +{ + const char **str_a = (const char **) a; + const char **str_b = (const char **) b; + + return strcmp(*str_a, *str_b); +} + +struct kallsyms_data { + unsigned long *addrs; + const char **syms; + size_t cnt; + size_t found; +}; + +static int kallsyms_callback(void *data, const char *name, + struct module *mod, unsigned long addr) +{ + struct kallsyms_data *args = data; + + if (!bsearch(&name, args->syms, args->cnt, sizeof(*args->syms), symbols_cmp)) + return 0; + + addr = ftrace_location(addr); + if (!addr) + return 0; + + args->addrs[args->found++] = addr; + return args->found == args->cnt ? 1 : 0; +} + +/** + * ftrace_lookup_symbols - Lookup addresses for array of symbols + * + * @sorted_syms: array of symbols pointers symbols to resolve, + * must be alphabetically sorted + * @cnt: number of symbols/addresses in @syms/@addrs arrays + * @addrs: array for storing resulting addresses + * + * This function looks up addresses for array of symbols provided in + * @syms array (must be alphabetically sorted) and stores them in + * @addrs array, which needs to be big enough to store at least @cnt + * addresses. + * + * This function returns 0 if all provided symbols are found, + * -ESRCH otherwise. + */ +int ftrace_lookup_symbols(const char **sorted_syms, size_t cnt, unsigned long *addrs) +{ + struct kallsyms_data args; + int err; + + args.addrs = addrs; + args.syms = sorted_syms; + args.cnt = cnt; + args.found = 0; + err = kallsyms_on_each_symbol(kallsyms_callback, &args); + if (err < 0) + return err; + return args.found == args.cnt ? 0 : -ESRCH; +} |