From patchwork Thu Jul 23 11:50:30 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: KP Singh X-Patchwork-Id: 11680725 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 2C5F013B4 for ; Thu, 23 Jul 2020 11:50:57 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id F0E17206E3 for ; Thu, 23 Jul 2020 11:50:56 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=chromium.org header.i=@chromium.org header.b="OHChvx0x" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728706AbgGWLu4 (ORCPT ); Thu, 23 Jul 2020 07:50:56 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:52792 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728574AbgGWLul (ORCPT ); Thu, 23 Jul 2020 07:50:41 -0400 Received: from mail-ej1-x644.google.com (mail-ej1-x644.google.com [IPv6:2a00:1450:4864:20::644]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id F1CD0C0619E6 for ; Thu, 23 Jul 2020 04:50:40 -0700 (PDT) Received: by mail-ej1-x644.google.com with SMTP id ga4so6030815ejb.11 for ; Thu, 23 Jul 2020 04:50:40 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=0IbOVQATaZAw50Bl/KPaWtmoVMybDo3GpqwoQPjlzk4=; b=OHChvx0xiWRzfZYo0Hl9rtu34xOAbx3/HolFh0EKjqbrIuBa6t9X8Bc3JWhLJiD8Sf L7JgJwJ5gRhWfRiq41YP3k/R9ZYMqjtA1sb0bFefqqABPLBkXUSywq/VSvH0EXnjXeG8 yR4bfBAT4yYK1inhT/kVFcUhfEB1/NWxIOkXw= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=0IbOVQATaZAw50Bl/KPaWtmoVMybDo3GpqwoQPjlzk4=; b=cqyeLInR8WMDhTby8RCqky4uC+MNBgjRJ2bPH6bOoda2Ix8GkVWszFZGGfWewFMNKk Ph0CYbv58BwSr/98EzcyxTlDInEPFwOQDHmbpVWDjCgP1fNShSa417BRfyCxJM0e+o1K 7gaqSkGmibN599Q4i5R+rjVUPZ9ezDbFllrLz+ePCeIJvuWBUXGy4doIzHuDL1cgFPkF XpubDo7pe4sc0WQ/q73+62rel0Uo9ggMBUIgnFgAvEURVEisTwtE/FYEGQMFwuHLNKex FDRbNnOEjGTRa1oBRen+8C5cvu6+ry+Tjp3kPMLKRxSfhzMVXrQshytnPDTtmgyc7Rnm nqJg== X-Gm-Message-State: AOAM532x4wNfe0epyz+F7SMBIpyPhBpHSIIibwzp3sNBYVuvaMJ8lC6y sAAOiMwOHy6bRmjNFsrBaoOxcA== X-Google-Smtp-Source: ABdhPJxcr2QJo42MZjlraagJdS3jQusAAvGK+G7LdN+1aFa/mzxsMxTeuXCpprbnemeT0CykG19K0Q== X-Received: by 2002:a17:906:6499:: with SMTP id e25mr3927190ejm.352.1595505039435; Thu, 23 Jul 2020 04:50:39 -0700 (PDT) Received: from kpsingh.zrh.corp.google.com ([81.6.44.51]) by smtp.gmail.com with ESMTPSA id h27sm579302eje.23.2020.07.23.04.50.38 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 23 Jul 2020 04:50:38 -0700 (PDT) From: KP Singh To: linux-kernel@vger.kernel.org, bpf@vger.kernel.org, linux-security-module@vger.kernel.org Cc: Alexei Starovoitov , Daniel Borkmann , Martin KaFai Lau , Paul Turner , Jann Horn , Florent Revest Subject: [PATCH bpf-next v6 5/7] bpf: Implement bpf_local_storage for inodes Date: Thu, 23 Jul 2020 13:50:30 +0200 Message-Id: <20200723115032.460770-6-kpsingh@chromium.org> X-Mailer: git-send-email 2.28.0.rc0.105.gf9edc3c819-goog In-Reply-To: <20200723115032.460770-1-kpsingh@chromium.org> References: <20200723115032.460770-1-kpsingh@chromium.org> MIME-Version: 1.0 Sender: owner-linux-security-module@vger.kernel.org Precedence: bulk List-ID: From: KP Singh Similar to bpf_local_storage for sockets, add local storage for inodes. The life-cycle of storage is managed with the life-cycle of the inode. i.e. the storage is destroyed along with the owning inode. The BPF LSM allocates an __rcu pointer to the bpf_local_storage in the security blob which are now stackable and can co-exist with other LSMs. Signed-off-by: KP Singh --- include/linux/bpf_local_storage.h | 10 + include/linux/bpf_lsm.h | 21 ++ include/linux/bpf_types.h | 3 + include/uapi/linux/bpf.h | 38 ++ kernel/bpf/Makefile | 1 + kernel/bpf/bpf_inode_storage.c | 353 ++++++++++++++++++ kernel/bpf/syscall.c | 3 +- kernel/bpf/verifier.c | 10 + security/bpf/hooks.c | 7 + .../bpf/bpftool/Documentation/bpftool-map.rst | 2 +- tools/bpf/bpftool/bash-completion/bpftool | 3 +- tools/bpf/bpftool/map.c | 3 +- tools/include/uapi/linux/bpf.h | 38 ++ tools/lib/bpf/libbpf_probes.c | 5 +- 14 files changed, 491 insertions(+), 6 deletions(-) create mode 100644 kernel/bpf/bpf_inode_storage.c diff --git a/include/linux/bpf_local_storage.h b/include/linux/bpf_local_storage.h index d80573b11d4c..49eaae723aa2 100644 --- a/include/linux/bpf_local_storage.h +++ b/include/linux/bpf_local_storage.h @@ -162,4 +162,14 @@ bpf_local_storage_update(void *owner, struct bpf_map *map, struct bpf_local_storage *local_storage, void *value, u64 map_flags); +#ifdef CONFIG_BPF_LSM +extern const struct bpf_func_proto bpf_inode_storage_get_proto; +extern const struct bpf_func_proto bpf_inode_storage_delete_proto; +void bpf_inode_storage_free(struct inode *inode); +#else +static inline void bpf_inode_storage_free(struct inode *inode) +{ +} +#endif /* CONFIG_BPF_LSM */ + #endif /* _BPF_LOCAL_STORAGE_H */ diff --git a/include/linux/bpf_lsm.h b/include/linux/bpf_lsm.h index af74712af585..d0683ada1e49 100644 --- a/include/linux/bpf_lsm.h +++ b/include/linux/bpf_lsm.h @@ -17,9 +17,24 @@ #include #undef LSM_HOOK +struct bpf_storage_blob { + struct bpf_local_storage __rcu *storage; +}; + +extern struct lsm_blob_sizes bpf_lsm_blob_sizes; + int bpf_lsm_verify_prog(struct bpf_verifier_log *vlog, const struct bpf_prog *prog); +static inline struct bpf_storage_blob *bpf_inode( + const struct inode *inode) +{ + if (unlikely(!inode->i_security)) + return NULL; + + return inode->i_security + bpf_lsm_blob_sizes.lbs_inode; +} + #else /* !CONFIG_BPF_LSM */ static inline int bpf_lsm_verify_prog(struct bpf_verifier_log *vlog, @@ -28,6 +43,12 @@ static inline int bpf_lsm_verify_prog(struct bpf_verifier_log *vlog, return -EOPNOTSUPP; } +static inline struct bpf_storage_blob *bpf_inode( + const struct inode *inode) +{ + return NULL; +} + #endif /* CONFIG_BPF_LSM */ #endif /* _LINUX_BPF_LSM_H */ diff --git a/include/linux/bpf_types.h b/include/linux/bpf_types.h index a52a5688418e..2e6f568377f1 100644 --- a/include/linux/bpf_types.h +++ b/include/linux/bpf_types.h @@ -107,6 +107,9 @@ BPF_MAP_TYPE(BPF_MAP_TYPE_SK_STORAGE, sk_storage_map_ops) BPF_MAP_TYPE(BPF_MAP_TYPE_SOCKMAP, sock_map_ops) BPF_MAP_TYPE(BPF_MAP_TYPE_SOCKHASH, sock_hash_ops) #endif +#ifdef CONFIG_BPF_LSM +BPF_MAP_TYPE(BPF_MAP_TYPE_INODE_STORAGE, inode_storage_map_ops) +#endif BPF_MAP_TYPE(BPF_MAP_TYPE_CPUMAP, cpu_map_ops) #if defined(CONFIG_XDP_SOCKETS) BPF_MAP_TYPE(BPF_MAP_TYPE_XSKMAP, xsk_map_ops) diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h index b9d2e4792d08..0bdfbe6067be 100644 --- a/include/uapi/linux/bpf.h +++ b/include/uapi/linux/bpf.h @@ -148,6 +148,7 @@ enum bpf_map_type { BPF_MAP_TYPE_DEVMAP_HASH, BPF_MAP_TYPE_STRUCT_OPS, BPF_MAP_TYPE_RINGBUF, + BPF_MAP_TYPE_INODE_STORAGE, }; /* Note that tracing related programs such as @@ -3377,6 +3378,41 @@ union bpf_attr { * A non-negative value equal to or less than *size* on success, * or a negative error in case of failure. * + * void *bpf_inode_storage_get(struct bpf_map *map, void *inode, void *value, u64 flags) + * Description + * Get a bpf_local_storage from an *inode*. + * + * Logically, it could be thought of as getting the value from + * a *map* with *inode* as the **key**. From this + * perspective, the usage is not much different from + * **bpf_map_lookup_elem**\ (*map*, **&**\ *inode*) except this + * helper enforces the key must be an inode and the map must also + * be a **BPF_MAP_TYPE_INODE_STORAGE**. + * + * Underneath, the value is stored locally at *inode* instead of + * the *map*. The *map* is used as the bpf-local-storage + * "type". The bpf-local-storage "type" (i.e. the *map*) is + * searched against all bpf_local_storage residing at *inode*. + * + * An optional *flags* (**BPF_LOCAL_STORAGE_GET_F_CREATE**) can be + * used such that a new bpf_local_storage will be + * created if one does not exist. *value* can be used + * together with **BPF_LOCAL_STORAGE_GET_F_CREATE** to specify + * the initial value of a bpf_local_storage. If *value* is + * **NULL**, the new bpf_local_storage will be zero initialized. + * Return + * A bpf_local_storage pointer is returned on success. + * + * **NULL** if not found or there was an error in adding + * a new bpf_local_storage. + * + * int bpf_inode_storage_delete(struct bpf_map *map, void *inode) + * Description + * Delete a bpf_local_storage from an *inode*. + * Return + * 0 on success. + * + * **-ENOENT** if the bpf_local_storage cannot be found. */ #define __BPF_FUNC_MAPPER(FN) \ FN(unspec), \ @@ -3521,6 +3557,8 @@ union bpf_attr { FN(skc_to_tcp_request_sock), \ FN(skc_to_udp6_sock), \ FN(get_task_stack), \ + FN(inode_storage_get), \ + FN(inode_storage_delete), \ /* */ /* integer value in 'imm' field of BPF_CALL instruction selects which helper diff --git a/kernel/bpf/Makefile b/kernel/bpf/Makefile index a9a147e18600..25f40588dfbf 100644 --- a/kernel/bpf/Makefile +++ b/kernel/bpf/Makefile @@ -5,6 +5,7 @@ CFLAGS_core.o += $(call cc-disable-warning, override-init) obj-$(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-$(CONFIG_BPF_SYSCALL) += hashtab.o arraymap.o percpu_freelist.o bpf_lru_list.o lpm_trie.o map_in_map.o obj-$(CONFIG_BPF_SYSCALL) += local_storage.o queue_stack_maps.o ringbuf.o +obj-${CONFIG_BPF_LSM} += bpf_inode_storage.o obj-$(CONFIG_BPF_SYSCALL) += disasm.o obj-$(CONFIG_BPF_JIT) += trampoline.o obj-$(CONFIG_BPF_SYSCALL) += btf.o diff --git a/kernel/bpf/bpf_inode_storage.c b/kernel/bpf/bpf_inode_storage.c new file mode 100644 index 000000000000..ebb54213f436 --- /dev/null +++ b/kernel/bpf/bpf_inode_storage.c @@ -0,0 +1,353 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (c) 2019 Facebook + * Copyright 2020 Google LLC. + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +DEFINE_BPF_STORAGE_CACHE(inode_cache); + +static struct bpf_local_storage_elem * +inode_selem_alloc(struct bpf_local_storage_map *smap, void *owner, + void *value, bool charge_omem) +{ + return bpf_selem_alloc(smap, value); +} + +static bool unlink_inode_storage(struct bpf_local_storage *local_storage, + struct bpf_local_storage_elem *selem, + bool uncharge_omem) +{ + struct bpf_storage_blob *bsb; + bool free_local_storage; + struct inode *inode; + + inode = local_storage->owner; + bsb = bpf_inode(inode); + if (!bsb) + return false; + + /* All uncharging on sk->sk_omem_alloc must be done first. + * sk may be freed once the last selem is unlinked from sk_storage. + */ + free_local_storage = hlist_is_singular_node(&selem->snode, + &local_storage->list); + + if (free_local_storage) { + /* After this RCU_INIT, sk may be freed and cannot be used */ + RCU_INIT_POINTER(bsb->storage, NULL); + local_storage->owner = NULL; + } + + return free_local_storage; + +} + +static struct bpf_local_storage_data *inode_storage_lookup(struct inode *inode, + struct bpf_map *map, + bool cacheit_lockit) +{ + struct bpf_local_storage *inode_storage; + struct bpf_local_storage_map *smap; + struct bpf_storage_blob *bsb; + + bsb = bpf_inode(inode); + if (!bsb) + return ERR_PTR(-ENOENT); + + inode_storage = rcu_dereference(bsb->storage); + if (!inode_storage) + return NULL; + + smap = (struct bpf_local_storage_map *)map; + return bpf_local_storage_lookup(inode_storage, smap, cacheit_lockit); +} + +static int inode_storage_alloc(void *owner, struct bpf_local_storage_map *smap, + struct bpf_local_storage_elem *first_selem) +{ + struct bpf_local_storage *curr; + struct bpf_storage_blob *bsb; + struct inode *inode = owner; + int err; + + bsb = bpf_inode(inode); + if (!bsb) + return -EINVAL; + + curr = bpf_local_storage_alloc(smap); + if (!curr) + return -ENOMEM; + + curr->owner = inode; + + bpf_selem_link_storage(curr, first_selem); + bpf_selem_link_map(smap, first_selem); + + err = bpf_local_storage_publish(first_selem, + (struct bpf_local_storage **)&bsb->storage, curr); + if (err) { + kfree(curr); + return err; + } + + return 0; +} + +static struct bpf_local_storage_data *inode_storage_update(void *owner, + struct bpf_map *map, + void *value, + u64 map_flags) +{ + struct bpf_local_storage_data *old_sdata = NULL; + struct bpf_local_storage_elem *selem; + struct bpf_local_storage *local_storage; + struct bpf_local_storage_map *smap; + struct bpf_storage_blob *bsb; + struct inode *inode; + int err; + + err = bpf_local_storage_check_update_flags(map, map_flags); + if (err) + return ERR_PTR(err); + + inode = owner; + bsb = bpf_inode(inode); + local_storage = rcu_dereference(bsb->storage); + smap = (struct bpf_local_storage_map *)map; + + if (!local_storage || hlist_empty(&local_storage->list)) { + /* Very first elem */ + selem = map->ops->map_selem_alloc(smap, owner, value, !old_sdata); + if (!selem) + return ERR_PTR(-ENOMEM); + + err = inode_storage_alloc(owner, smap, selem); + if (err) { + kfree(selem); + return ERR_PTR(err); + } + + return SDATA(selem); + } + + return bpf_local_storage_update(owner, map, local_storage, value, + map_flags); +} + + +void bpf_inode_storage_free(struct inode *inode) +{ + struct bpf_local_storage_elem *selem; + struct bpf_local_storage *local_storage; + bool free_inode_storage = false; + struct bpf_storage_blob *bsb; + struct hlist_node *n; + + bsb = bpf_inode(inode); + if (!bsb) + return; + + rcu_read_lock(); + + local_storage = rcu_dereference(bsb->storage); + if (!local_storage) { + rcu_read_unlock(); + return; + } + + /* Netiher the bpf_prog nor the bpf-map's syscall + * could be modifying the local_storage->list now. + * Thus, no elem can be added-to or deleted-from the + * local_storage->list by the bpf_prog or by the bpf-map's syscall. + * + * It is racing with bpf_local_storage_map_free() alone + * when unlinking elem from the local_storage->list and + * the map's bucket->list. + */ + raw_spin_lock_bh(&local_storage->lock); + hlist_for_each_entry_safe(selem, n, &local_storage->list, snode) { + /* Always unlink from map before unlinking from + * local_storage. + */ + bpf_selem_unlink_map(selem); + free_inode_storage = + bpf_selem_unlink_storage(local_storage, selem, false); + } + raw_spin_unlock_bh(&local_storage->lock); + rcu_read_unlock(); + + /* free_inoode_storage should always be true as long as + * local_storage->list was non-empty. + */ + if (free_inode_storage) + kfree_rcu(local_storage, rcu); +} + + +static void *bpf_fd_inode_storage_lookup_elem(struct bpf_map *map, void *key) +{ + struct bpf_local_storage_data *sdata; + struct file *f; + int fd; + + fd = *(int *)key; + f = fcheck(fd); + if (!f) + return ERR_PTR(-EINVAL); + + sdata = inode_storage_lookup(f->f_inode, map, true); + return sdata ? sdata->data : NULL; +} + +static int bpf_fd_inode_storage_update_elem(struct bpf_map *map, void *key, + void *value, u64 map_flags) +{ + struct bpf_local_storage_data *sdata; + struct file *f; + int fd; + + fd = *(int *)key; + f = fcheck(fd); + if (!f) + return -EINVAL; + + sdata = inode_storage_update(f->f_inode, map, value, map_flags); + return PTR_ERR_OR_ZERO(sdata); +} + +static int inode_storage_delete(struct inode *inode, struct bpf_map *map) +{ + struct bpf_local_storage_data *sdata; + + sdata = inode_storage_lookup(inode, map, false); + if (!sdata) + return -ENOENT; + + bpf_selem_unlink(SELEM(sdata)); + + return 0; +} + +static int bpf_fd_inode_storage_delete_elem(struct bpf_map *map, void *key) +{ + struct file *f; + int fd; + + fd = *(int *)key; + f = fcheck(fd); + if (!f) + return -EINVAL; + + return inode_storage_delete(f->f_inode, map); +} + +BPF_CALL_4(bpf_inode_storage_get, struct bpf_map *, map, struct inode *, inode, + void *, value, u64, flags) +{ + struct bpf_local_storage_data *sdata; + + if (flags & ~(BPF_LOCAL_STORAGE_GET_F_CREATE)) + return (unsigned long)NULL; + + sdata = inode_storage_lookup(inode, map, true); + if (sdata) + return (unsigned long)sdata->data; + + if (flags & BPF_LOCAL_STORAGE_GET_F_CREATE) { + sdata = inode_storage_update(inode, map, value, BPF_NOEXIST); + return IS_ERR(sdata) ? + (unsigned long)NULL : (unsigned long)sdata->data; + } + + return (unsigned long)NULL; +} + +BPF_CALL_2(bpf_inode_storage_delete, + struct bpf_map *, map, struct inode *, inode) +{ + return inode_storage_delete(inode, map); +} + +static int notsupp_get_next_key(struct bpf_map *map, void *key, + void *next_key) +{ + return -ENOTSUPP; +} + +static struct bpf_map *inode_storage_map_alloc(union bpf_attr *attr) +{ + struct bpf_local_storage_map *smap; + + smap = bpf_local_storage_map_alloc(attr); + if (IS_ERR(smap)) + return ERR_CAST(smap); + + smap->cache_idx = bpf_local_storage_cache_idx_get(&inode_cache); + return &smap->map; +} + +static void inode_storage_map_free(struct bpf_map *map) +{ + struct bpf_local_storage_map *smap; + + smap = (struct bpf_local_storage_map *)map; + bpf_local_storage_cache_idx_free(&inode_cache, smap->cache_idx); + bpf_local_storage_map_free(smap); +} + +static int inode_storage_map_btf_id; +const struct bpf_map_ops inode_storage_map_ops = { + .map_alloc_check = bpf_local_storage_map_alloc_check, + .map_alloc = inode_storage_map_alloc, + .map_free = inode_storage_map_free, + .map_get_next_key = notsupp_get_next_key, + .map_lookup_elem = bpf_fd_inode_storage_lookup_elem, + .map_update_elem = bpf_fd_inode_storage_update_elem, + .map_delete_elem = bpf_fd_inode_storage_delete_elem, + .map_check_btf = bpf_local_storage_map_check_btf, + .map_btf_name = "bpf_local_storage_map", + .map_btf_id = &inode_storage_map_btf_id, + .map_selem_alloc = inode_selem_alloc, + .map_local_storage_update = inode_storage_update, + .map_local_storage_unlink = unlink_inode_storage, +}; + +BTF_ID_LIST(bpf_inode_storage_get_btf_ids) +BTF_ID(struct, inode) + +const struct bpf_func_proto bpf_inode_storage_get_proto = { + .func = bpf_inode_storage_get, + .gpl_only = false, + .ret_type = RET_PTR_TO_MAP_VALUE_OR_NULL, + .arg1_type = ARG_CONST_MAP_PTR, + .arg2_type = ARG_PTR_TO_BTF_ID, + .arg3_type = ARG_PTR_TO_MAP_VALUE_OR_NULL, + .arg4_type = ARG_ANYTHING, + .btf_id = bpf_inode_storage_get_btf_ids, +}; + +BTF_ID_LIST(bpf_inode_storage_delete_btf_ids) +BTF_ID(struct, inode) + +const struct bpf_func_proto bpf_inode_storage_delete_proto = { + .func = bpf_inode_storage_delete, + .gpl_only = false, + .ret_type = RET_INTEGER, + .arg1_type = ARG_CONST_MAP_PTR, + .arg2_type = ARG_PTR_TO_BTF_ID, + .btf_id = bpf_inode_storage_delete_btf_ids, +}; diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c index ee290b1f2d9e..cd47fb11b6dc 100644 --- a/kernel/bpf/syscall.c +++ b/kernel/bpf/syscall.c @@ -768,7 +768,8 @@ static int map_check_btf(struct bpf_map *map, const struct btf *btf, if (map->map_type != BPF_MAP_TYPE_HASH && map->map_type != BPF_MAP_TYPE_ARRAY && map->map_type != BPF_MAP_TYPE_CGROUP_STORAGE && - map->map_type != BPF_MAP_TYPE_SK_STORAGE) + map->map_type != BPF_MAP_TYPE_SK_STORAGE && + map->map_type != BPF_MAP_TYPE_INODE_STORAGE) return -ENOTSUPP; if (map->spin_lock_off + sizeof(struct bpf_spin_lock) > map->value_size) { diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c index 9a6703bc3f36..238bf6c9fd05 100644 --- a/kernel/bpf/verifier.c +++ b/kernel/bpf/verifier.c @@ -4167,6 +4167,11 @@ static int check_map_func_compatibility(struct bpf_verifier_env *env, func_id != BPF_FUNC_sk_storage_delete) goto error; break; + case BPF_MAP_TYPE_INODE_STORAGE: + if (func_id != BPF_FUNC_inode_storage_get && + func_id != BPF_FUNC_inode_storage_delete) + goto error; + break; default: break; } @@ -4240,6 +4245,11 @@ static int check_map_func_compatibility(struct bpf_verifier_env *env, if (map->map_type != BPF_MAP_TYPE_SK_STORAGE) goto error; break; + case BPF_FUNC_inode_storage_get: + case BPF_FUNC_inode_storage_delete: + if (map->map_type != BPF_MAP_TYPE_INODE_STORAGE) + goto error; + break; default: break; } diff --git a/security/bpf/hooks.c b/security/bpf/hooks.c index 32d32d485451..35f9b19259e5 100644 --- a/security/bpf/hooks.c +++ b/security/bpf/hooks.c @@ -3,6 +3,7 @@ /* * Copyright (C) 2020 Google LLC. */ +#include #include #include @@ -11,6 +12,7 @@ static struct security_hook_list bpf_lsm_hooks[] __lsm_ro_after_init = { LSM_HOOK_INIT(NAME, bpf_lsm_##NAME), #include #undef LSM_HOOK + LSM_HOOK_INIT(inode_free_security, bpf_inode_storage_free), }; static int __init bpf_lsm_init(void) @@ -20,7 +22,12 @@ static int __init bpf_lsm_init(void) return 0; } +struct lsm_blob_sizes bpf_lsm_blob_sizes __lsm_ro_after_init = { + .lbs_inode = sizeof(struct bpf_storage_blob), +}; + DEFINE_LSM(bpf) = { .name = "bpf", .init = bpf_lsm_init, + .blobs = &bpf_lsm_blob_sizes }; diff --git a/tools/bpf/bpftool/Documentation/bpftool-map.rst b/tools/bpf/bpftool/Documentation/bpftool-map.rst index 41e2a74252d0..083db6c2fc67 100644 --- a/tools/bpf/bpftool/Documentation/bpftool-map.rst +++ b/tools/bpf/bpftool/Documentation/bpftool-map.rst @@ -49,7 +49,7 @@ MAP COMMANDS | | **lru_percpu_hash** | **lpm_trie** | **array_of_maps** | **hash_of_maps** | | **devmap** | **devmap_hash** | **sockmap** | **cpumap** | **xskmap** | **sockhash** | | **cgroup_storage** | **reuseport_sockarray** | **percpu_cgroup_storage** -| | **queue** | **stack** | **sk_storage** | **struct_ops** | **ringbuf** } +| | **queue** | **stack** | **sk_storage** | **struct_ops** | **ringbuf** | **inode_storage** } DESCRIPTION =========== diff --git a/tools/bpf/bpftool/bash-completion/bpftool b/tools/bpf/bpftool/bash-completion/bpftool index 7b137264ea3a..bccdffb70e23 100644 --- a/tools/bpf/bpftool/bash-completion/bpftool +++ b/tools/bpf/bpftool/bash-completion/bpftool @@ -688,7 +688,8 @@ _bpftool() lru_percpu_hash lpm_trie array_of_maps \ hash_of_maps devmap devmap_hash sockmap cpumap \ xskmap sockhash cgroup_storage reuseport_sockarray \ - percpu_cgroup_storage queue stack' -- \ + percpu_cgroup_storage queue stack sk_storage \ + struct_ops inode_storage' -- \ "$cur" ) ) return 0 ;; diff --git a/tools/bpf/bpftool/map.c b/tools/bpf/bpftool/map.c index 3a27d31a1856..bc0071228f88 100644 --- a/tools/bpf/bpftool/map.c +++ b/tools/bpf/bpftool/map.c @@ -50,6 +50,7 @@ const char * const map_type_name[] = { [BPF_MAP_TYPE_SK_STORAGE] = "sk_storage", [BPF_MAP_TYPE_STRUCT_OPS] = "struct_ops", [BPF_MAP_TYPE_RINGBUF] = "ringbuf", + [BPF_MAP_TYPE_INODE_STORAGE] = "inode_storage", }; const size_t map_type_name_size = ARRAY_SIZE(map_type_name); @@ -1442,7 +1443,7 @@ static int do_help(int argc, char **argv) " lru_percpu_hash | lpm_trie | array_of_maps | hash_of_maps |\n" " devmap | devmap_hash | sockmap | cpumap | xskmap | sockhash |\n" " cgroup_storage | reuseport_sockarray | percpu_cgroup_storage |\n" - " queue | stack | sk_storage | struct_ops | ringbuf }\n" + " queue | stack | sk_storage | struct_ops | ringbuf | inode_storage }\n" " " HELP_SPEC_OPTIONS "\n" "", bin_name, argv[-2]); diff --git a/tools/include/uapi/linux/bpf.h b/tools/include/uapi/linux/bpf.h index b9d2e4792d08..0bdfbe6067be 100644 --- a/tools/include/uapi/linux/bpf.h +++ b/tools/include/uapi/linux/bpf.h @@ -148,6 +148,7 @@ enum bpf_map_type { BPF_MAP_TYPE_DEVMAP_HASH, BPF_MAP_TYPE_STRUCT_OPS, BPF_MAP_TYPE_RINGBUF, + BPF_MAP_TYPE_INODE_STORAGE, }; /* Note that tracing related programs such as @@ -3377,6 +3378,41 @@ union bpf_attr { * A non-negative value equal to or less than *size* on success, * or a negative error in case of failure. * + * void *bpf_inode_storage_get(struct bpf_map *map, void *inode, void *value, u64 flags) + * Description + * Get a bpf_local_storage from an *inode*. + * + * Logically, it could be thought of as getting the value from + * a *map* with *inode* as the **key**. From this + * perspective, the usage is not much different from + * **bpf_map_lookup_elem**\ (*map*, **&**\ *inode*) except this + * helper enforces the key must be an inode and the map must also + * be a **BPF_MAP_TYPE_INODE_STORAGE**. + * + * Underneath, the value is stored locally at *inode* instead of + * the *map*. The *map* is used as the bpf-local-storage + * "type". The bpf-local-storage "type" (i.e. the *map*) is + * searched against all bpf_local_storage residing at *inode*. + * + * An optional *flags* (**BPF_LOCAL_STORAGE_GET_F_CREATE**) can be + * used such that a new bpf_local_storage will be + * created if one does not exist. *value* can be used + * together with **BPF_LOCAL_STORAGE_GET_F_CREATE** to specify + * the initial value of a bpf_local_storage. If *value* is + * **NULL**, the new bpf_local_storage will be zero initialized. + * Return + * A bpf_local_storage pointer is returned on success. + * + * **NULL** if not found or there was an error in adding + * a new bpf_local_storage. + * + * int bpf_inode_storage_delete(struct bpf_map *map, void *inode) + * Description + * Delete a bpf_local_storage from an *inode*. + * Return + * 0 on success. + * + * **-ENOENT** if the bpf_local_storage cannot be found. */ #define __BPF_FUNC_MAPPER(FN) \ FN(unspec), \ @@ -3521,6 +3557,8 @@ union bpf_attr { FN(skc_to_tcp_request_sock), \ FN(skc_to_udp6_sock), \ FN(get_task_stack), \ + FN(inode_storage_get), \ + FN(inode_storage_delete), \ /* */ /* integer value in 'imm' field of BPF_CALL instruction selects which helper diff --git a/tools/lib/bpf/libbpf_probes.c b/tools/lib/bpf/libbpf_probes.c index 5a3d3f078408..daaad635d0ed 100644 --- a/tools/lib/bpf/libbpf_probes.c +++ b/tools/lib/bpf/libbpf_probes.c @@ -173,7 +173,7 @@ int libbpf__load_raw_btf(const char *raw_types, size_t types_len, return btf_fd; } -static int load_sk_storage_btf(void) +static int load_local_storage_btf(void) { const char strs[] = "\0bpf_spin_lock\0val\0cnt\0l"; /* struct bpf_spin_lock { @@ -232,12 +232,13 @@ bool bpf_probe_map_type(enum bpf_map_type map_type, __u32 ifindex) key_size = 0; break; case BPF_MAP_TYPE_SK_STORAGE: + case BPF_MAP_TYPE_INODE_STORAGE: btf_key_type_id = 1; btf_value_type_id = 3; value_size = 8; max_entries = 0; map_flags = BPF_F_NO_PREALLOC; - btf_fd = load_sk_storage_btf(); + btf_fd = load_local_storage_btf(); if (btf_fd < 0) return false; break;