From patchwork Mon Apr 18 21:15:57 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Matthias Kaehlcke X-Patchwork-Id: 12817105 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 947BAC433EF for ; Mon, 18 Apr 2022 21:16:19 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S240926AbiDRVS5 (ORCPT ); Mon, 18 Apr 2022 17:18:57 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:53058 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1347976AbiDRVSs (ORCPT ); Mon, 18 Apr 2022 17:18:48 -0400 Received: from mail-pg1-x531.google.com (mail-pg1-x531.google.com [IPv6:2607:f8b0:4864:20::531]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id EFD752CE28 for ; Mon, 18 Apr 2022 14:16:07 -0700 (PDT) Received: by mail-pg1-x531.google.com with SMTP id u2so21092146pgq.10 for ; Mon, 18 Apr 2022 14:16:07 -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=3NUaPl7T9VDjPF5pSPc597gsFG5v6iWsZQaLgLfeQww=; b=UBDOLR+Mh24DHdsNmC7ttDSdUYYhK71ZxlqJFIvEiPoTYFmr87XRbhqUuJe0zKDfii TXW8I3yWCcvYyiqCHPxV7WfB/4n0bNzymbHzIArdU4+e6O3lq47ucuRYaCgHGlvDjSGO B20sYxYIBFP2mUCRci3ZuhiR27q5GeyeAYpPg= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=3NUaPl7T9VDjPF5pSPc597gsFG5v6iWsZQaLgLfeQww=; b=V+QKtRiGcYF4sQQRR78aEH/yMg2bv3I4qPTAGGl0AMeASZlRvC/Hym70++kFdH9gB9 zUoh1Wddoesoy/d8O+MgsPRsvYF9QB1COevPsSoHcQ2FS5Sb0FpQh2ts6Unbdvq0bMSa aCtDTv58SVsS2KpXFyokr9vr8LR3t/PJsfj0DzkLk8LLzzFiqkK3bx6fKeRwC5g8fnUg r9OTfqQlP6K866kABsQYBNr2EU9d/LNFLtbVzsWt2hXdzmLKDN+UOl0etc/C5jRkOv9c 0NOxCsHGOTWeiac/MsYkonNgnG9QG2vNhqfoyGIRbZCmkW9RG4zqw73Z6+qETnMAqEBs QJMA== X-Gm-Message-State: AOAM530rlWzxIFw/G3VzkAcGThz9WnWB2vUQJ5TIpZGqXFc0Uq4p7BoW VJ0g4PcJkgMsiQrkYTmOxZGO/Q== X-Google-Smtp-Source: ABdhPJyQQEFDCs5IVHAM/UnOWzfEHFGUzBQrHu06Pf6Bm6srYRBFZ5pue0X3KWczqh0V440cxpFgFA== X-Received: by 2002:a05:6a00:1786:b0:50a:7f5a:e280 with SMTP id s6-20020a056a00178600b0050a7f5ae280mr4803956pfg.25.1650316567469; Mon, 18 Apr 2022 14:16:07 -0700 (PDT) Received: from localhost ([2620:15c:202:201:6b32:a0a5:ec32:c287]) by smtp.gmail.com with UTF8SMTPSA id w13-20020a17090a5e0d00b001c7d4099670sm13858457pjf.28.2022.04.18.14.16.05 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Mon, 18 Apr 2022 14:16:06 -0700 (PDT) From: Matthias Kaehlcke To: Alasdair Kergon , Mike Snitzer , Kees Cook , James Morris , "Serge E . Hallyn" Cc: linux-raid@vger.kernel.org, linux-kernel@vger.kernel.org, Song Liu , linux-security-module@vger.kernel.org, Douglas Anderson , dm-devel@redhat.com, Matthias Kaehlcke Subject: [PATCH 1/3] dm: Add verity helpers for LoadPin Date: Mon, 18 Apr 2022 14:15:57 -0700 Message-Id: <20220418141545.1.I3e928575a23481121e73286874c4c2bdb403355d@changeid> X-Mailer: git-send-email 2.36.0.rc0.470.gd361397f0d-goog In-Reply-To: <20220418211559.3832724-1-mka@chromium.org> References: <20220418211559.3832724-1-mka@chromium.org> MIME-Version: 1.0 Precedence: bulk List-ID: LoadPin limits loading of kernel modules, firmware and certain other files to a 'pinned' file system (typically a read-only rootfs). To provide more flexibility LoadPin is being extended to also allow loading these files from trusted dm-verity devices. For that purpose LoadPin can be provided with a list of verity root digests that it should consider as trusted. Add a bunch of helpers to allow LoadPin to check whether a DM device is a trusted verity device. The new functions broadly fall in two categories: those that need access to verity internals (like the root digest), and the 'glue' between LoadPin and verity. The new file dm-verity-loadpin.c contains the glue functions. Signed-off-by: Matthias Kaehlcke --- drivers/md/Makefile | 6 +++ drivers/md/dm-verity-loadpin.c | 80 +++++++++++++++++++++++++++++++ drivers/md/dm-verity-target.c | 34 +++++++++++++ drivers/md/dm-verity.h | 4 ++ include/linux/dm-verity-loadpin.h | 27 +++++++++++ 5 files changed, 151 insertions(+) create mode 100644 drivers/md/dm-verity-loadpin.c create mode 100644 include/linux/dm-verity-loadpin.h diff --git a/drivers/md/Makefile b/drivers/md/Makefile index 0454b0885b01..e12cd004d375 100644 --- a/drivers/md/Makefile +++ b/drivers/md/Makefile @@ -100,6 +100,12 @@ ifeq ($(CONFIG_IMA),y) dm-mod-objs += dm-ima.o endif +ifeq ($(CONFIG_DM_VERITY),y) +ifeq ($(CONFIG_SECURITY_LOADPIN),y) +dm-mod-objs += dm-verity-loadpin.o +endif +endif + ifeq ($(CONFIG_DM_VERITY_FEC),y) dm-verity-objs += dm-verity-fec.o endif diff --git a/drivers/md/dm-verity-loadpin.c b/drivers/md/dm-verity-loadpin.c new file mode 100644 index 000000000000..972ca93a2231 --- /dev/null +++ b/drivers/md/dm-verity-loadpin.c @@ -0,0 +1,80 @@ +// SPDX-License-Identifier: GPL-2.0-only + +#include +#include +#include + +#include "dm.h" +#include "dm-verity.h" + +static struct list_head *trusted_root_digests; + +/* + * Sets the root digests of verity devices which LoadPin considers as trusted. + * + * This function must only be called once. + */ +void dm_verity_loadpin_set_trusted_root_digests(struct list_head *digests) +{ + if (!trusted_root_digests) + trusted_root_digests = digests; + else + pr_warn("verity root digests trusted by LoadPin are already set!!!\n"); +} + +static bool is_trusted_verity_target(struct dm_target *ti) +{ + u8 *root_digest; + unsigned int digest_size; + struct trusted_root_digest *trd; + bool trusted = false; + + if (!dm_is_verity_target(ti)) + return false; + + if (dm_verity_get_root_digest(ti, &root_digest, &digest_size)) + return false; + + list_for_each_entry(trd, trusted_root_digests, node) { + if ((trd->len == digest_size) && + !memcmp(trd->data, root_digest, digest_size)) { + trusted = true; + break; + } + } + + kfree(root_digest); + + return trusted; +} + +/* + * Determines whether a mapped device is a verity device that is trusted + * by LoadPin. + */ +bool dm_verity_loadpin_is_md_trusted(struct mapped_device *md) +{ + int srcu_idx; + struct dm_table *table; + unsigned int num_targets; + bool trusted = false; + int i; + + if (!trusted_root_digests || list_empty(trusted_root_digests)) + return false; + + table = dm_get_live_table(md, &srcu_idx); + num_targets = dm_table_get_num_targets(table); + for (i = 0; i < num_targets; i++) { + struct dm_target *ti = dm_table_get_target(table, i); + + if (is_trusted_verity_target(ti)) { + trusted = true; + break; + } + } + + dm_put_live_table(md, srcu_idx); + + return trusted; +} diff --git a/drivers/md/dm-verity-target.c b/drivers/md/dm-verity-target.c index 80133aae0db3..6bea9692cd39 100644 --- a/drivers/md/dm-verity-target.c +++ b/drivers/md/dm-verity-target.c @@ -16,9 +16,11 @@ #include "dm-verity.h" #include "dm-verity-fec.h" #include "dm-verity-verify-sig.h" +#include #include #include #include +#include #define DM_MSG_PREFIX "verity" @@ -1310,6 +1312,38 @@ static int verity_ctr(struct dm_target *ti, unsigned argc, char **argv) return r; } +/* + * Check whether a DM target is a verity target. + */ +bool dm_is_verity_target(struct dm_target *ti) +{ + return ti->type->module == THIS_MODULE; +} +EXPORT_SYMBOL_GPL(dm_is_verity_target); + +/* + * Get the root digest of a verity target. + * + * Returns a copy of the root digests, the caller is responsible for + * freeing the memory of the digest. + */ +int dm_verity_get_root_digest(struct dm_target *ti, u8 **root_digest, unsigned int *digest_size) +{ + struct dm_verity *v = ti->private; + + if (!dm_is_verity_target(ti)) + return -EINVAL; + + *root_digest = kmemdup(v->root_digest, v->digest_size, GFP_KERNEL); + if (*root_digest == NULL) + return -ENOMEM; + + *digest_size = v->digest_size; + + return 0; +} +EXPORT_SYMBOL_GPL(dm_verity_get_root_digest); + static struct target_type verity_target = { .name = "verity", .version = {1, 8, 0}, diff --git a/drivers/md/dm-verity.h b/drivers/md/dm-verity.h index 4e769d13473a..c832cc3e3d24 100644 --- a/drivers/md/dm-verity.h +++ b/drivers/md/dm-verity.h @@ -129,4 +129,8 @@ extern int verity_hash(struct dm_verity *v, struct ahash_request *req, extern int verity_hash_for_block(struct dm_verity *v, struct dm_verity_io *io, sector_t block, u8 *digest, bool *is_zero); +extern bool dm_is_verity_target(struct dm_target *ti); +extern int dm_verity_get_root_digest(struct dm_target *ti, u8 **root_digest, + unsigned int *digest_size); + #endif /* DM_VERITY_H */ diff --git a/include/linux/dm-verity-loadpin.h b/include/linux/dm-verity-loadpin.h new file mode 100644 index 000000000000..12a86911d05a --- /dev/null +++ b/include/linux/dm-verity-loadpin.h @@ -0,0 +1,27 @@ +/* SPDX-License-Identifier: GPL-2.0 */ + +#ifndef __LINUX_DM_VERITY_LOADPIN_H +#define __LINUX_DM_VERITY_LOADPIN_H + +#include + +struct mapped_device; + +struct trusted_root_digest { + u8 *data; + unsigned int len; + struct list_head node; +}; + +#if IS_ENABLED(CONFIG_SECURITY_LOADPIN) && IS_BUILTIN(CONFIG_DM_VERITY) +void dm_verity_loadpin_set_trusted_root_digests(struct list_head *digests); +bool dm_verity_loadpin_is_md_trusted(struct mapped_device *md); +#else +static inline void dm_verity_loadpin_set_trusted_root_digests(struct list_head *digests) {} +static inline bool dm_verity_loadpin_is_md_trusted(struct mapped_device *md) +{ + return false; +} +#endif + +#endif /* __LINUX_DM_LOADPIN_H */ From patchwork Mon Apr 18 21:15:58 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Matthias Kaehlcke X-Patchwork-Id: 12817106 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 750DBC433F5 for ; Mon, 18 Apr 2022 21:16:20 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1347973AbiDRVS6 (ORCPT ); Mon, 18 Apr 2022 17:18:58 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:53196 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1347983AbiDRVS4 (ORCPT ); Mon, 18 Apr 2022 17:18:56 -0400 Received: from mail-pg1-x52d.google.com (mail-pg1-x52d.google.com [IPv6:2607:f8b0:4864:20::52d]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 009D62CE1E for ; 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Mon, 18 Apr 2022 14:16:09 -0700 (PDT) Received: from localhost ([2620:15c:202:201:6b32:a0a5:ec32:c287]) by smtp.gmail.com with UTF8SMTPSA id n24-20020aa79058000000b0050612d0fe01sm13406325pfo.2.2022.04.18.14.16.08 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Mon, 18 Apr 2022 14:16:08 -0700 (PDT) From: Matthias Kaehlcke To: Alasdair Kergon , Mike Snitzer , Kees Cook , James Morris , "Serge E . Hallyn" Cc: linux-raid@vger.kernel.org, linux-kernel@vger.kernel.org, Song Liu , linux-security-module@vger.kernel.org, Douglas Anderson , dm-devel@redhat.com, Matthias Kaehlcke Subject: [PATCH 2/3] LoadPin: Enable loading from trusted dm-verity devices Date: Mon, 18 Apr 2022 14:15:58 -0700 Message-Id: <20220418141545.2.I01c67af41d2f6525c6d023101671d7339a9bc8b5@changeid> X-Mailer: git-send-email 2.36.0.rc0.470.gd361397f0d-goog In-Reply-To: <20220418211559.3832724-1-mka@chromium.org> References: <20220418211559.3832724-1-mka@chromium.org> MIME-Version: 1.0 Precedence: bulk List-ID: Extend LoadPin to allow loading of kernel files from trusted dm-verity [1] devices. This change adds the concept of trusted verity devices to LoadPin. Userspace can use the new systl file 'loadpin/trusted_verity_root_digests' to provide LoadPin with a list of root digests from dm-verity devices that LoadPin should consider as trusted. When a kernel file is read LoadPin first checks (as usual) whether the file is located on the pinned root, if so the file can be loaded. Otherwise, if the verity extension is enabled, LoadPin determines whether the file is located on a verity backed device and whether the root digest of that device is in the list of trusted digests. The file can be loaded if the verity device has a trusted root digest. The list of trusted root digests can only be written once (typically at boot time), to limit the possiblity of attackers setting up rogue verity devices and marking them as trusted. Background: As of now LoadPin restricts loading of kernel files to a single pinned filesystem, typically the rootfs. This works for many systems, however it can result in a bloated rootfs (and OTA updates) on platforms where multiple boards with different hardware configurations use the same rootfs image. Especially when 'optional' files are large it may be preferable to download/install them only when they are actually needed by a given board. Chrome OS uses Downloadable Content (DLC) [2] to deploy certain 'packages' at runtime. As an example a DLC package could contain firmware for a peripheral that is not present on all boards. DLCs use dm-verity to verify the integrity of the DLC content. [1] https://www.kernel.org/doc/html/latest/admin-guide/device-mapper/verity.html [2] https://chromium.googlesource.com/chromiumos/platform2/+/HEAD/dlcservice/docs/developer.md Signed-off-by: Matthias Kaehlcke Reported-by: kernel test robot --- security/loadpin/Kconfig | 11 +++ security/loadpin/loadpin.c | 168 ++++++++++++++++++++++++++++++++++++- 2 files changed, 178 insertions(+), 1 deletion(-) diff --git a/security/loadpin/Kconfig b/security/loadpin/Kconfig index 91be65dec2ab..cf3e6431e02d 100644 --- a/security/loadpin/Kconfig +++ b/security/loadpin/Kconfig @@ -18,3 +18,14 @@ config SECURITY_LOADPIN_ENFORCE If selected, LoadPin will enforce pinning at boot. If not selected, it can be enabled at boot with the kernel parameter "loadpin.enforce=1". + +config SECURITY_LOADPIN_VERITY + bool "Allow reading files from certain other filesystems that use dm-verity" + depends on DM_VERITY=y + help + If selected LoadPin can allow reading files from filesystems + that use dm-verity. A verity filesystem can be configured as + being trusted by LoadPin by writing its root digest to the + sysctl file 'trusted_verity_root_digests'. The sysctl file + can only be written once (typically at boot) and accepts a + list of comma separated digests. diff --git a/security/loadpin/loadpin.c b/security/loadpin/loadpin.c index b12f7d986b1e..b9c174f8687d 100644 --- a/security/loadpin/loadpin.c +++ b/security/loadpin/loadpin.c @@ -18,6 +18,8 @@ #include #include /* current */ #include +#include +#include static void report_load(const char *origin, struct file *file, char *operation) { @@ -43,6 +45,10 @@ static char *exclude_read_files[READING_MAX_ID]; static int ignore_read_file_id[READING_MAX_ID] __ro_after_init; static struct super_block *pinned_root; static DEFINE_SPINLOCK(pinned_root_spinlock); +#ifdef CONFIG_SECURITY_LOADPIN_VERITY +static bool verity_digests_set; +static LIST_HEAD(trusted_verity_root_digests); +#endif #ifdef CONFIG_SYSCTL @@ -65,6 +71,144 @@ static struct ctl_table loadpin_sysctl_table[] = { { } }; +#ifdef CONFIG_SECURITY_LOADPIN_VERITY + +static int proc_verity_root_digests(struct ctl_table *table, int write, + void *buffer, size_t *lenp, loff_t *ppos) +{ + struct trusted_root_digest *trd; + char *buf; + int rc; + + if (write) { + struct ctl_table tbl = *table; + char *p, *d; + + if (*ppos) + return -EINVAL; + + if (verity_digests_set) + return -EPERM; + + buf = kzalloc(tbl.maxlen, GFP_KERNEL); + if (!buf) + return -ENOMEM; + + tbl.data = buf; + + rc = proc_dostring(&tbl, write, buffer, lenp, ppos); + if (rc) { + kfree(buf); + return rc; + } + + if (strlen(buf) == 0) { + verity_digests_set = true; + return false; + } + + p = buf; + while ((d = strsep(&p, ",")) != NULL) { + int len = strlen(d); + + if (len % 2) { + rc = -EINVAL; + goto err; + } + + len /= 2; + + trd = kzalloc(sizeof(*trd), GFP_KERNEL); + if (!trd) { + rc = -ENOMEM; + goto err; + } + + list_add_tail(&trd->node, &trusted_verity_root_digests); + + trd->data = kzalloc(len, GFP_KERNEL); + if (!trd->data) { + rc = -ENOMEM; + goto err; + } + + if (hex2bin(trd->data, d, len)) { + rc = -EINVAL; + goto err; + } + + trd->len = len; + } + + kfree(buf); + + if (!list_empty(&trusted_verity_root_digests)) { + dm_verity_loadpin_set_trusted_root_digests(&trusted_verity_root_digests); + verity_digests_set = true; + } + } else { + struct ctl_table tbl = { .maxlen = 0 }; + size_t off = 0; + + list_for_each_entry(trd, &trusted_verity_root_digests, node) { + /* two ASCII characters per byte and a comma / '\0' */ + tbl.maxlen += (trd->len * 2) + 1; + } + + tbl.data = kzalloc(tbl.maxlen, GFP_KERNEL); + + list_for_each_entry(trd, &trusted_verity_root_digests, node) { + int i; + + if (off > 0) { + snprintf(tbl.data + off, tbl.maxlen - off, ","); + off++; + } + + for (i = 0; i < trd->len; i++) { + snprintf(tbl.data + off, tbl.maxlen - off, "%02x", trd->data[i]); + off += 2; + } + } + + proc_dostring(&tbl, write, buffer, lenp, ppos); + kfree(tbl.data); + } + + return 0; + +err: + kfree(buf); + + { + struct trusted_root_digest *tmp; + + list_for_each_entry_safe(trd, tmp, &trusted_verity_root_digests, node) { + kfree(trd->data); + list_del(&trd->node); + kfree(trd); + } + } + + return rc; +} + +static struct ctl_table loadpin_sysctl_table_verity[] = { + { + .procname = "trusted_verity_root_digests", + .maxlen = SZ_4K, + .mode = 0644, + .proc_handler = proc_verity_root_digests, + }, + + { } +}; +#else + +static struct ctl_table loadpin_sysctl_table_verity[] = {}; + +#endif /* CONFIG_SECURITY_LOADPIN_VERITY */ + /* * This must be called after early kernel init, since then the rootdev * is available. @@ -118,6 +262,20 @@ static void loadpin_sb_free_security(struct super_block *mnt_sb) } } +static bool loadpin_is_fs_trusted(struct super_block *sb) +{ + struct mapped_device *md = dm_get_md(sb->s_bdev->bd_dev); + bool trusted; + + if (!md) + return false; + + trusted = dm_verity_loadpin_is_md_trusted(md); + dm_put(md); + + return trusted; +} + static int loadpin_read_file(struct file *file, enum kernel_read_file_id id, bool contents) { @@ -174,7 +332,8 @@ static int loadpin_read_file(struct file *file, enum kernel_read_file_id id, spin_unlock(&pinned_root_spinlock); } - if (IS_ERR_OR_NULL(pinned_root) || load_root != pinned_root) { + if (IS_ERR_OR_NULL(pinned_root) || + ((load_root != pinned_root) && !loadpin_is_fs_trusted(load_root))) { if (unlikely(!enforce)) { report_load(origin, file, "pinning-ignored"); return 0; @@ -240,6 +399,13 @@ static int __init loadpin_init(void) enforce ? "" : "not "); parse_exclude(); security_add_hooks(loadpin_hooks, ARRAY_SIZE(loadpin_hooks), "loadpin"); + + if (IS_ENABLED(CONFIG_SECURITY_LOADPIN_VERITY)) { + if (!register_sysctl_paths(loadpin_sysctl_path, + loadpin_sysctl_table_verity)) + pr_notice("sysctl registration failed!\n"); + } + return 0; } From patchwork Mon Apr 18 21:15:59 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Matthias Kaehlcke X-Patchwork-Id: 12817107 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 2A704C43217 for ; Mon, 18 Apr 2022 21:16:21 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1347983AbiDRVS7 (ORCPT ); Mon, 18 Apr 2022 17:18:59 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:53196 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1347993AbiDRVS5 (ORCPT ); Mon, 18 Apr 2022 17:18:57 -0400 Received: from mail-pl1-x630.google.com (mail-pl1-x630.google.com [IPv6:2607:f8b0:4864:20::630]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 223E82D1C1 for ; Mon, 18 Apr 2022 14:16:12 -0700 (PDT) Received: by mail-pl1-x630.google.com with SMTP id c12so13345667plr.6 for ; Mon, 18 Apr 2022 14:16:12 -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=qm/BmS5rZykflggAWLelmGp8fWeLhZCgEzC+nt/A6s4=; b=jOGlGDc4Wz6w//dtoJeqZYjBwmgJ9X0uBmiWSlHHhhny2QoTzwVyv3a/QnVezngt8l 3ttINehXise0pulBtGu+lsTlr5/YM61z/YnIc3bJtEjb2TyAH4JhublL+rlgv5TvhhtK wp3ot4iekb0EvbU7nv54WtdXLzyXLG7sI6Sbs= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=qm/BmS5rZykflggAWLelmGp8fWeLhZCgEzC+nt/A6s4=; b=zBKCTMFVK85IYoN5tnYL4vOrfpuijYST7TqSx3/dZ/fqiycJRqBqAwuX1XgjsytEDS l9iQnX2f7aJnZD2JSOpzbIw/dUhI0fyKQg3q98a54hSkGrvorv6cwfzuuqlwuR224hDO jbVDngOLcxFiPF5NKslr0vn9YKk/0rRSTTTYd+eYRkwLgnpG6RhGlfEPDkebUup0THC9 1hpnEScXwx4f6Iw83dlertCT422aKrLLiwZu3qCzLjUeLFNgkE5/uAMjKcG04WWmT394 mU3jW8hRQrwNuNr16D1oIBUVOTHYi7K8LvMIPU2nsDpnvadRzMFo830cpHWJexDzezFH ILKg== X-Gm-Message-State: AOAM531FuOacq44sf94osbYEB8MC8cYOWDfwy4jaEE62dXoSY5FKjw/o DfZVzgun062zms8OQrMN/Uhj+g== X-Google-Smtp-Source: ABdhPJwvT6hPqXjTca3Xc2+bb0JBOY7ovGiOak9BOvmgcSEBCUg/Tyd1ChxcMzkWocvs0mSZVqmGYw== X-Received: by 2002:a17:90b:4b01:b0:1d2:abf5:c83f with SMTP id lx1-20020a17090b4b0100b001d2abf5c83fmr4999347pjb.93.1650316571711; Mon, 18 Apr 2022 14:16:11 -0700 (PDT) Received: from localhost ([2620:15c:202:201:6b32:a0a5:ec32:c287]) by smtp.gmail.com with UTF8SMTPSA id d16-20020a17090a02d000b001cba39c88fcsm1487068pjd.0.2022.04.18.14.16.10 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Mon, 18 Apr 2022 14:16:11 -0700 (PDT) From: Matthias Kaehlcke To: Alasdair Kergon , Mike Snitzer , Kees Cook , James Morris , "Serge E . Hallyn" Cc: linux-raid@vger.kernel.org, linux-kernel@vger.kernel.org, Song Liu , linux-security-module@vger.kernel.org, Douglas Anderson , dm-devel@redhat.com, Matthias Kaehlcke Subject: [PATCH 3/3] dm: verity-loadpin: Use CONFIG_SECURITY_LOADPIN_VERITY for conditional compilation Date: Mon, 18 Apr 2022 14:15:59 -0700 Message-Id: <20220418141545.3.I5aca2dcc3b06de4bf53696cd21329dce8272b8aa@changeid> X-Mailer: git-send-email 2.36.0.rc0.470.gd361397f0d-goog In-Reply-To: <20220418211559.3832724-1-mka@chromium.org> References: <20220418211559.3832724-1-mka@chromium.org> MIME-Version: 1.0 Precedence: bulk List-ID: The verity glue for LoadPin is only needed when CONFIG_SECURITY_LOADPIN_VERITY is set, use this option for conditional compilation instead of the combo of CONFIG_DM_VERITY and CONFIG_SECURITY_LOADPIN. Signed-off-by: Matthias Kaehlcke --- drivers/md/Makefile | 7 +------ include/linux/dm-verity-loadpin.h | 2 +- 2 files changed, 2 insertions(+), 7 deletions(-) diff --git a/drivers/md/Makefile b/drivers/md/Makefile index e12cd004d375..a96441752ec7 100644 --- a/drivers/md/Makefile +++ b/drivers/md/Makefile @@ -83,6 +83,7 @@ obj-$(CONFIG_DM_LOG_WRITES) += dm-log-writes.o obj-$(CONFIG_DM_INTEGRITY) += dm-integrity.o obj-$(CONFIG_DM_ZONED) += dm-zoned.o obj-$(CONFIG_DM_WRITECACHE) += dm-writecache.o +obj-$(CONFIG_SECURITY_LOADPIN_VERITY) += dm-verity-loadpin.o ifeq ($(CONFIG_DM_INIT),y) dm-mod-objs += dm-init.o @@ -100,12 +101,6 @@ ifeq ($(CONFIG_IMA),y) dm-mod-objs += dm-ima.o endif -ifeq ($(CONFIG_DM_VERITY),y) -ifeq ($(CONFIG_SECURITY_LOADPIN),y) -dm-mod-objs += dm-verity-loadpin.o -endif -endif - ifeq ($(CONFIG_DM_VERITY_FEC),y) dm-verity-objs += dm-verity-fec.o endif diff --git a/include/linux/dm-verity-loadpin.h b/include/linux/dm-verity-loadpin.h index 12a86911d05a..be63ac76f98d 100644 --- a/include/linux/dm-verity-loadpin.h +++ b/include/linux/dm-verity-loadpin.h @@ -13,7 +13,7 @@ struct trusted_root_digest { struct list_head node; }; -#if IS_ENABLED(CONFIG_SECURITY_LOADPIN) && IS_BUILTIN(CONFIG_DM_VERITY) +#if IS_ENABLED(CONFIG_SECURITY_LOADPIN_VERITY) void dm_verity_loadpin_set_trusted_root_digests(struct list_head *digests); bool dm_verity_loadpin_is_md_trusted(struct mapped_device *md); #else