diff options
Diffstat (limited to 'security')
| -rw-r--r-- | security/Kconfig.hardening | 14 | ||||
| -rw-r--r-- | security/landlock/fs.c | 48 | ||||
| -rw-r--r-- | security/loadpin/Kconfig | 7 | ||||
| -rw-r--r-- | security/loadpin/loadpin.c | 16 | ||||
| -rw-r--r-- | security/security.c | 4 | ||||
| -rw-r--r-- | security/selinux/hooks.c | 24 | ||||
| -rw-r--r-- | security/selinux/include/classmap.h | 2 | ||||
| -rw-r--r-- | security/smack/smack.h | 9 | ||||
| -rw-r--r-- | security/smack/smack_lsm.c | 52 |
9 files changed, 134 insertions, 42 deletions
diff --git a/security/Kconfig.hardening b/security/Kconfig.hardening index bd2aabb2c60f..995bc42003e6 100644 --- a/security/Kconfig.hardening +++ b/security/Kconfig.hardening @@ -22,11 +22,17 @@ menu "Memory initialization" config CC_HAS_AUTO_VAR_INIT_PATTERN def_bool $(cc-option,-ftrivial-auto-var-init=pattern) -config CC_HAS_AUTO_VAR_INIT_ZERO - # GCC ignores the -enable flag, so we can test for the feature with - # a single invocation using the flag, but drop it as appropriate in - # the Makefile, depending on the presence of Clang. +config CC_HAS_AUTO_VAR_INIT_ZERO_BARE + def_bool $(cc-option,-ftrivial-auto-var-init=zero) + +config CC_HAS_AUTO_VAR_INIT_ZERO_ENABLER + # Clang 16 and later warn about using the -enable flag, but it + # is required before then. def_bool $(cc-option,-ftrivial-auto-var-init=zero -enable-trivial-auto-var-init-zero-knowing-it-will-be-removed-from-clang) + depends on !CC_HAS_AUTO_VAR_INIT_ZERO_BARE + +config CC_HAS_AUTO_VAR_INIT_ZERO + def_bool CC_HAS_AUTO_VAR_INIT_ZERO_BARE || CC_HAS_AUTO_VAR_INIT_ZERO_ENABLER choice prompt "Initialize kernel stack variables at function entry" diff --git a/security/landlock/fs.c b/security/landlock/fs.c index ec5a6247cd3e..a9dbd99d9ee7 100644 --- a/security/landlock/fs.c +++ b/security/landlock/fs.c @@ -150,6 +150,16 @@ retry: /* clang-format on */ /* + * All access rights that are denied by default whether they are handled or not + * by a ruleset/layer. This must be ORed with all ruleset->fs_access_masks[] + * entries when we need to get the absolute handled access masks. + */ +/* clang-format off */ +#define ACCESS_INITIALLY_DENIED ( \ + LANDLOCK_ACCESS_FS_REFER) +/* clang-format on */ + +/* * @path: Should have been checked by get_path_from_fd(). */ int landlock_append_fs_rule(struct landlock_ruleset *const ruleset, @@ -167,7 +177,9 @@ int landlock_append_fs_rule(struct landlock_ruleset *const ruleset, return -EINVAL; /* Transforms relative access rights to absolute ones. */ - access_rights |= LANDLOCK_MASK_ACCESS_FS & ~ruleset->fs_access_masks[0]; + access_rights |= + LANDLOCK_MASK_ACCESS_FS & + ~(ruleset->fs_access_masks[0] | ACCESS_INITIALLY_DENIED); object = get_inode_object(d_backing_inode(path->dentry)); if (IS_ERR(object)) return PTR_ERR(object); @@ -277,23 +289,12 @@ static inline bool is_nouser_or_private(const struct dentry *dentry) static inline access_mask_t get_handled_accesses(const struct landlock_ruleset *const domain) { - access_mask_t access_dom = 0; - unsigned long access_bit; - - for (access_bit = 0; access_bit < LANDLOCK_NUM_ACCESS_FS; - access_bit++) { - size_t layer_level; + access_mask_t access_dom = ACCESS_INITIALLY_DENIED; + size_t layer_level; - for (layer_level = 0; layer_level < domain->num_layers; - layer_level++) { - if (domain->fs_access_masks[layer_level] & - BIT_ULL(access_bit)) { - access_dom |= BIT_ULL(access_bit); - break; - } - } - } - return access_dom; + for (layer_level = 0; layer_level < domain->num_layers; layer_level++) + access_dom |= domain->fs_access_masks[layer_level]; + return access_dom & LANDLOCK_MASK_ACCESS_FS; } static inline access_mask_t @@ -316,8 +317,13 @@ init_layer_masks(const struct landlock_ruleset *const domain, for_each_set_bit(access_bit, &access_req, ARRAY_SIZE(*layer_masks)) { - if (domain->fs_access_masks[layer_level] & - BIT_ULL(access_bit)) { + /* + * Artificially handles all initially denied by default + * access rights. + */ + if (BIT_ULL(access_bit) & + (domain->fs_access_masks[layer_level] | + ACCESS_INITIALLY_DENIED)) { (*layer_masks)[access_bit] |= BIT_ULL(layer_level); handled_accesses |= BIT_ULL(access_bit); @@ -857,10 +863,6 @@ static int current_check_refer_path(struct dentry *const old_dentry, NULL, NULL); } - /* Backward compatibility: no reparenting support. */ - if (!(get_handled_accesses(dom) & LANDLOCK_ACCESS_FS_REFER)) - return -EXDEV; - access_request_parent1 |= LANDLOCK_ACCESS_FS_REFER; access_request_parent2 |= LANDLOCK_ACCESS_FS_REFER; diff --git a/security/loadpin/Kconfig b/security/loadpin/Kconfig index 70e7985b2561..6724eaba3d36 100644 --- a/security/loadpin/Kconfig +++ b/security/loadpin/Kconfig @@ -33,4 +33,9 @@ config SECURITY_LOADPIN_VERITY on the LoadPin securityfs entry 'dm-verity'. The ioctl expects a file descriptor of a file with verity digests as parameter. The file must be located on the pinned root and - contain a comma separated list of digests. + start with the line: + + # LOADPIN_TRUSTED_VERITY_ROOT_DIGESTS + + This is followed by the verity digests, with one digest per + line. diff --git a/security/loadpin/loadpin.c b/security/loadpin/loadpin.c index 44521582dcba..de41621f4998 100644 --- a/security/loadpin/loadpin.c +++ b/security/loadpin/loadpin.c @@ -21,6 +21,8 @@ #include <linux/dm-verity-loadpin.h> #include <uapi/linux/loadpin.h> +#define VERITY_DIGEST_FILE_HEADER "# LOADPIN_TRUSTED_VERITY_ROOT_DIGESTS" + static void report_load(const char *origin, struct file *file, char *operation) { char *cmdline, *pathname; @@ -292,9 +294,21 @@ static int read_trusted_verity_root_digests(unsigned int fd) p = strim(data); while ((d = strsep(&p, "\n")) != NULL) { - int len = strlen(d); + int len; struct dm_verity_loadpin_trusted_root_digest *trd; + if (d == data) { + /* first line, validate header */ + if (strcmp(d, VERITY_DIGEST_FILE_HEADER)) { + rc = -EPROTO; + goto err; + } + + continue; + } + + len = strlen(d); + if (len % 2) { rc = -EPROTO; goto err; diff --git a/security/security.c b/security/security.c index 14d30fec8a00..4b95de24bc8d 100644 --- a/security/security.c +++ b/security/security.c @@ -2660,4 +2660,8 @@ int security_uring_sqpoll(void) { return call_int_hook(uring_sqpoll, 0); } +int security_uring_cmd(struct io_uring_cmd *ioucmd) +{ + return call_int_hook(uring_cmd, 0, ioucmd); +} #endif /* CONFIG_IO_URING */ diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c index 79573504783b..03bca97c8b29 100644 --- a/security/selinux/hooks.c +++ b/security/selinux/hooks.c @@ -91,6 +91,7 @@ #include <uapi/linux/mount.h> #include <linux/fsnotify.h> #include <linux/fanotify.h> +#include <linux/io_uring.h> #include "avc.h" #include "objsec.h" @@ -6987,6 +6988,28 @@ static int selinux_uring_sqpoll(void) return avc_has_perm(&selinux_state, sid, sid, SECCLASS_IO_URING, IO_URING__SQPOLL, NULL); } + +/** + * selinux_uring_cmd - check if IORING_OP_URING_CMD is allowed + * @ioucmd: the io_uring command structure + * + * Check to see if the current domain is allowed to execute an + * IORING_OP_URING_CMD against the device/file specified in @ioucmd. + * + */ +static int selinux_uring_cmd(struct io_uring_cmd *ioucmd) +{ + struct file *file = ioucmd->file; + struct inode *inode = file_inode(file); + struct inode_security_struct *isec = selinux_inode(inode); + struct common_audit_data ad; + + ad.type = LSM_AUDIT_DATA_FILE; + ad.u.file = file; + + return avc_has_perm(&selinux_state, current_sid(), isec->sid, + SECCLASS_IO_URING, IO_URING__CMD, &ad); +} #endif /* CONFIG_IO_URING */ /* @@ -7231,6 +7254,7 @@ static struct security_hook_list selinux_hooks[] __lsm_ro_after_init = { #ifdef CONFIG_IO_URING LSM_HOOK_INIT(uring_override_creds, selinux_uring_override_creds), LSM_HOOK_INIT(uring_sqpoll, selinux_uring_sqpoll), + LSM_HOOK_INIT(uring_cmd, selinux_uring_cmd), #endif /* diff --git a/security/selinux/include/classmap.h b/security/selinux/include/classmap.h index ff757ae5f253..1c2f41ff4e55 100644 --- a/security/selinux/include/classmap.h +++ b/security/selinux/include/classmap.h @@ -253,7 +253,7 @@ const struct security_class_mapping secclass_map[] = { { "anon_inode", { COMMON_FILE_PERMS, NULL } }, { "io_uring", - { "override_creds", "sqpoll", NULL } }, + { "override_creds", "sqpoll", "cmd", NULL } }, { NULL } }; diff --git a/security/smack/smack.h b/security/smack/smack.h index fc837dcebf96..e2239be7bd60 100644 --- a/security/smack/smack.h +++ b/security/smack/smack.h @@ -180,15 +180,6 @@ struct smack_known_list_elem { struct smack_known *smk_label; }; -/* Super block security struct flags for mount options */ -#define FSDEFAULT_MNT 0x01 -#define FSFLOOR_MNT 0x02 -#define FSHAT_MNT 0x04 -#define FSROOT_MNT 0x08 -#define FSTRANS_MNT 0x10 - -#define NUM_SMK_MNT_OPTS 5 - enum { Opt_error = -1, Opt_fsdefault = 0, diff --git a/security/smack/smack_lsm.c b/security/smack/smack_lsm.c index 001831458fa2..dadcb9941da5 100644 --- a/security/smack/smack_lsm.c +++ b/security/smack/smack_lsm.c @@ -42,6 +42,7 @@ #include <linux/fs_context.h> #include <linux/fs_parser.h> #include <linux/watch_queue.h> +#include <linux/io_uring.h> #include "smack.h" #define TRANS_TRUE "TRUE" @@ -496,13 +497,11 @@ static int smack_ptrace_access_check(struct task_struct *ctp, unsigned int mode) */ static int smack_ptrace_traceme(struct task_struct *ptp) { - int rc; struct smack_known *skp; skp = smk_of_task(smack_cred(current_cred())); - rc = smk_ptrace_rule_check(ptp, skp, PTRACE_MODE_ATTACH, __func__); - return rc; + return smk_ptrace_rule_check(ptp, skp, PTRACE_MODE_ATTACH, __func__); } /** @@ -2279,6 +2278,21 @@ static void smack_sk_free_security(struct sock *sk) } /** + * smack_sk_clone_security - Copy security context + * @sk: the old socket + * @newsk: the new socket + * + * Copy the security context of the old socket pointer to the cloned + */ +static void smack_sk_clone_security(const struct sock *sk, struct sock *newsk) +{ + struct socket_smack *ssp_old = sk->sk_security; + struct socket_smack *ssp_new = newsk->sk_security; + + *ssp_new = *ssp_old; +} + +/** * smack_ipv4host_label - check host based restrictions * @sip: the object end * @@ -4732,6 +4746,36 @@ static int smack_uring_sqpoll(void) return -EPERM; } +/** + * smack_uring_cmd - check on file operations for io_uring + * @ioucmd: the command in question + * + * Make a best guess about whether a io_uring "command" should + * be allowed. Use the same logic used for determining if the + * file could be opened for read in the absence of better criteria. + */ +static int smack_uring_cmd(struct io_uring_cmd *ioucmd) +{ + struct file *file = ioucmd->file; + struct smk_audit_info ad; + struct task_smack *tsp; + struct inode *inode; + int rc; + + if (!file) + return -EINVAL; + + tsp = smack_cred(file->f_cred); + inode = file_inode(file); + + smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_PATH); + smk_ad_setfield_u_fs_path(&ad, file->f_path); + rc = smk_tskacc(tsp, smk_of_inode(inode), MAY_READ, &ad); + rc = smk_bu_credfile(file->f_cred, file, MAY_READ, rc); + + return rc; +} + #endif /* CONFIG_IO_URING */ struct lsm_blob_sizes smack_blob_sizes __lsm_ro_after_init = { @@ -4851,6 +4895,7 @@ static struct security_hook_list smack_hooks[] __lsm_ro_after_init = { LSM_HOOK_INIT(socket_getpeersec_dgram, smack_socket_getpeersec_dgram), LSM_HOOK_INIT(sk_alloc_security, smack_sk_alloc_security), LSM_HOOK_INIT(sk_free_security, smack_sk_free_security), + LSM_HOOK_INIT(sk_clone_security, smack_sk_clone_security), LSM_HOOK_INIT(sock_graft, smack_sock_graft), LSM_HOOK_INIT(inet_conn_request, smack_inet_conn_request), LSM_HOOK_INIT(inet_csk_clone, smack_inet_csk_clone), @@ -4889,6 +4934,7 @@ static struct security_hook_list smack_hooks[] __lsm_ro_after_init = { #ifdef CONFIG_IO_URING LSM_HOOK_INIT(uring_override_creds, smack_uring_override_creds), LSM_HOOK_INIT(uring_sqpoll, smack_uring_sqpoll), + LSM_HOOK_INIT(uring_cmd, smack_uring_cmd), #endif }; |