X-Git-Url: https://git.proxmox.com/?a=blobdiff_plain;f=security%2Fsecurity.c;h=24f28cfc0a31fcf20ce1bbe0daf9336d881f3701;hb=1013a2337996024b0ccb28e99d3aea2fb9b7f4ff;hp=9ffa9e9c5c554a6939cf175560a617414ce38a00;hpb=ffb1e76f4f32d2b8ea4189df0484980370476395;p=mirror_ubuntu-jammy-kernel.git diff --git a/security/security.c b/security/security.c index 9ffa9e9c5c55..24f28cfc0a31 100644 --- a/security/security.c +++ b/security/security.c @@ -29,6 +29,7 @@ #include #include #include +#include #define MAX_LSM_EVM_XATTR 2 @@ -77,7 +78,14 @@ static struct kmem_cache *lsm_file_cache; static struct kmem_cache *lsm_inode_cache; char *lsm_names; -static struct lsm_blob_sizes blob_sizes __lsm_ro_after_init; + +/* + * The task blob includes the "display" slot used for + * chosing which module presents contexts. + */ +static struct lsm_blob_sizes blob_sizes __lsm_ro_after_init = { + .lbs_task = sizeof(int), +}; /* Boot-time LSM user choice */ static __initdata const char *chosen_lsm_order; @@ -205,6 +213,7 @@ static void __init lsm_set_blob_sizes(struct lsm_blob_sizes *needed) lsm_set_blob_size(&needed->lbs_ipc, &blob_sizes.lbs_ipc); lsm_set_blob_size(&needed->lbs_msg_msg, &blob_sizes.lbs_msg_msg); lsm_set_blob_size(&needed->lbs_superblock, &blob_sizes.lbs_superblock); + lsm_set_blob_size(&needed->lbs_sock, &blob_sizes.lbs_sock); lsm_set_blob_size(&needed->lbs_task, &blob_sizes.lbs_task); } @@ -341,7 +350,9 @@ static void __init ordered_lsm_init(void) init_debug("ipc blob size = %d\n", blob_sizes.lbs_ipc); init_debug("msg_msg blob size = %d\n", blob_sizes.lbs_msg_msg); init_debug("superblock blob size = %d\n", blob_sizes.lbs_superblock); + init_debug("sock blob size = %d\n", blob_sizes.lbs_sock); init_debug("task blob size = %d\n", blob_sizes.lbs_task); + init_debug("lsmblob size = %zu\n", sizeof(struct lsmblob)); /* * Create any kmem_caches needed for blobs @@ -469,21 +480,39 @@ static int lsm_append(const char *new, char **result) return 0; } +/* + * Current index to use while initializing the lsmblob secid list. + * Pointers to the LSM id structures for local use. + */ +static int lsm_slot __lsm_ro_after_init; +static struct lsm_id *lsm_slotlist[LSMBLOB_ENTRIES]; + /** * security_add_hooks - Add a modules hooks to the hook lists. * @hooks: the hooks to add * @count: the number of hooks to add - * @lsm: the name of the security module + * @lsmid: the the identification information for the security module * * Each LSM has to register its hooks with the infrastructure. + * If the LSM is using hooks that export secids allocate a slot + * for it in the lsmblob. */ void __init security_add_hooks(struct security_hook_list *hooks, int count, - char *lsm) + struct lsm_id *lsmid) { int i; + if (lsmid->slot == LSMBLOB_NEEDED) { + if (lsm_slot >= LSMBLOB_ENTRIES) + panic("%s Too many LSMs registered.\n", __func__); + lsm_slotlist[lsm_slot] = lsmid; + lsmid->slot = lsm_slot++; + init_debug("%s assigned lsmblob slot %d\n", lsmid->lsm, + lsmid->slot); + } + for (i = 0; i < count; i++) { - hooks[i].lsm = lsm; + hooks[i].lsmid = lsmid; hlist_add_tail_rcu(&hooks[i].list, hooks[i].head); } @@ -492,7 +521,7 @@ void __init security_add_hooks(struct security_hook_list *hooks, int count, * and fix this up afterwards. */ if (slab_is_available()) { - if (lsm_append(lsm, &lsm_names) < 0) + if (lsm_append(lsmid->lsm, &lsm_names) < 0) panic("%s - Cannot get early memory.\n", __func__); } } @@ -606,6 +635,8 @@ int lsm_inode_alloc(struct inode *inode) */ static int lsm_task_alloc(struct task_struct *task) { + int *display; + if (blob_sizes.lbs_task == 0) { task->security = NULL; return 0; @@ -614,6 +645,15 @@ static int lsm_task_alloc(struct task_struct *task) task->security = kzalloc(blob_sizes.lbs_task, GFP_KERNEL); if (task->security == NULL) return -ENOMEM; + + /* + * The start of the task blob contains the "display" LSM slot number. + * Start with it set to the invalid slot number, indicating that the + * default first registered LSM be displayed. + */ + display = task->security; + *display = LSMBLOB_INVALID; + return 0; } @@ -659,6 +699,28 @@ static int lsm_msg_msg_alloc(struct msg_msg *mp) return 0; } +/** + * lsm_sock_alloc - allocate a composite sock blob + * @sock: the sock that needs a blob + * @priority: allocation mode + * + * Allocate the sock blob for all the modules + * + * Returns 0, or -ENOMEM if memory can't be allocated. + */ +static int lsm_sock_alloc(struct sock *sock, gfp_t priority) +{ + if (blob_sizes.lbs_sock == 0) { + sock->sk_security = NULL; + return 0; + } + + sock->sk_security = kzalloc(blob_sizes.lbs_sock, priority); + if (sock->sk_security == NULL) + return -ENOMEM; + return 0; +} + /** * lsm_early_task - during initialization allocate a composite task blob * @task: the task that needs a blob @@ -751,24 +813,28 @@ int security_binder_set_context_mgr(struct task_struct *mgr) { return call_int_hook(binder_set_context_mgr, 0, mgr); } +EXPORT_SYMBOL(security_binder_set_context_mgr); int security_binder_transaction(struct task_struct *from, struct task_struct *to) { return call_int_hook(binder_transaction, 0, from, to); } +EXPORT_SYMBOL(security_binder_transaction); int security_binder_transfer_binder(struct task_struct *from, struct task_struct *to) { return call_int_hook(binder_transfer_binder, 0, from, to); } +EXPORT_SYMBOL(security_binder_transfer_binder); int security_binder_transfer_file(struct task_struct *from, struct task_struct *to, struct file *file) { return call_int_hook(binder_transfer_file, 0, from, to, file); } +EXPORT_SYMBOL(security_binder_transfer_file); int security_ptrace_access_check(struct task_struct *child, unsigned int mode) { @@ -1461,9 +1527,16 @@ int security_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer } EXPORT_SYMBOL(security_inode_listsecurity); -void security_inode_getsecid(struct inode *inode, u32 *secid) +void security_inode_getsecid(struct inode *inode, struct lsmblob *blob) { - call_void_hook(inode_getsecid, inode, secid); + struct security_hook_list *hp; + + lsmblob_init(blob, 0); + hlist_for_each_entry(hp, &security_hook_heads.inode_getsecid, list) { + if (WARN_ON(hp->lsmid->slot < 0 || hp->lsmid->slot >= lsm_slot)) + continue; + hp->hook.inode_getsecid(inode, &blob->secid[hp->lsmid->slot]); + } } int security_inode_copy_up(struct dentry *src, struct cred **new) @@ -1640,14 +1713,26 @@ int security_file_open(struct file *file) int security_task_alloc(struct task_struct *task, unsigned long clone_flags) { + int *odisplay = current->security; + int *ndisplay; int rc = lsm_task_alloc(task); - if (rc) + if (unlikely(rc)) return rc; + rc = call_int_hook(task_alloc, 0, task, clone_flags); - if (unlikely(rc)) + if (unlikely(rc)) { security_task_free(task); - return rc; + return rc; + } + + if (odisplay) { + ndisplay = task->security; + if (ndisplay) + *ndisplay = *odisplay; + } + + return 0; } void security_task_free(struct task_struct *task) @@ -1704,16 +1789,32 @@ void security_transfer_creds(struct cred *new, const struct cred *old) call_void_hook(cred_transfer, new, old); } -void security_cred_getsecid(const struct cred *c, u32 *secid) +void security_cred_getsecid(const struct cred *c, struct lsmblob *blob) { - *secid = 0; - call_void_hook(cred_getsecid, c, secid); + struct security_hook_list *hp; + + lsmblob_init(blob, 0); + hlist_for_each_entry(hp, &security_hook_heads.cred_getsecid, list) { + if (WARN_ON(hp->lsmid->slot < 0 || hp->lsmid->slot >= lsm_slot)) + continue; + hp->hook.cred_getsecid(c, &blob->secid[hp->lsmid->slot]); + } } EXPORT_SYMBOL(security_cred_getsecid); -int security_kernel_act_as(struct cred *new, u32 secid) +int security_kernel_act_as(struct cred *new, struct lsmblob *blob) { - return call_int_hook(kernel_act_as, 0, new, secid); + struct security_hook_list *hp; + int rc; + + hlist_for_each_entry(hp, &security_hook_heads.kernel_act_as, list) { + if (WARN_ON(hp->lsmid->slot < 0 || hp->lsmid->slot >= lsm_slot)) + continue; + rc = hp->hook.kernel_act_as(new, blob->secid[hp->lsmid->slot]); + if (rc != 0) + return rc; + } + return 0; } int security_kernel_create_files_as(struct cred *new, struct inode *inode) @@ -1807,17 +1908,29 @@ int security_task_getsid(struct task_struct *p) return call_int_hook(task_getsid, 0, p); } -void security_task_getsecid_subj(struct task_struct *p, u32 *secid) +void security_task_getsecid_subj(struct task_struct *p, struct lsmblob *blob) { - *secid = 0; - call_void_hook(task_getsecid_subj, p, secid); + struct security_hook_list *hp; + + lsmblob_init(blob, 0); + hlist_for_each_entry(hp, &security_hook_heads.task_getsecid_subj, list) { + if (WARN_ON(hp->lsmid->slot < 0 || hp->lsmid->slot >= lsm_slot)) + continue; + hp->hook.task_getsecid_subj(p, &blob->secid[hp->lsmid->slot]); + } } EXPORT_SYMBOL(security_task_getsecid_subj); -void security_task_getsecid_obj(struct task_struct *p, u32 *secid) +void security_task_getsecid_obj(struct task_struct *p, struct lsmblob *blob) { - *secid = 0; - call_void_hook(task_getsecid_obj, p, secid); + struct security_hook_list *hp; + + lsmblob_init(blob, 0); + hlist_for_each_entry(hp, &security_hook_heads.task_getsecid_obj, list) { + if (WARN_ON(hp->lsmid->slot < 0 || hp->lsmid->slot >= lsm_slot)) + continue; + hp->hook.task_getsecid_obj(p, &blob->secid[hp->lsmid->slot]); + } } EXPORT_SYMBOL(security_task_getsecid_obj); @@ -1897,10 +2010,16 @@ int security_ipc_permission(struct kern_ipc_perm *ipcp, short flag) return call_int_hook(ipc_permission, 0, ipcp, flag); } -void security_ipc_getsecid(struct kern_ipc_perm *ipcp, u32 *secid) +void security_ipc_getsecid(struct kern_ipc_perm *ipcp, struct lsmblob *blob) { - *secid = 0; - call_void_hook(ipc_getsecid, ipcp, secid); + struct security_hook_list *hp; + + lsmblob_init(blob, 0); + hlist_for_each_entry(hp, &security_hook_heads.ipc_getsecid, list) { + if (WARN_ON(hp->lsmid->slot < 0 || hp->lsmid->slot >= lsm_slot)) + continue; + hp->hook.ipc_getsecid(ipcp, &blob->secid[hp->lsmid->slot]); + } } int security_msg_msg_alloc(struct msg_msg *msg) @@ -2044,22 +2163,109 @@ int security_getprocattr(struct task_struct *p, const char *lsm, char *name, char **value) { struct security_hook_list *hp; + int display = lsm_task_display(current); + int slot = 0; + + if (!strcmp(name, "display")) { + /* + * lsm_slot will be 0 if there are no displaying modules. + */ + if (lsm_slot == 0) + return -EINVAL; + + /* + * Only allow getting the current process' display. + * There are too few reasons to get another process' + * display and too many LSM policy issues. + */ + if (current != p) + return -EINVAL; + + display = lsm_task_display(p); + if (display != LSMBLOB_INVALID) + slot = display; + *value = kstrdup(lsm_slotlist[slot]->lsm, GFP_KERNEL); + if (*value) + return strlen(*value); + return -ENOMEM; + } hlist_for_each_entry(hp, &security_hook_heads.getprocattr, list) { - if (lsm != NULL && strcmp(lsm, hp->lsm)) + if (lsm != NULL && strcmp(lsm, hp->lsmid->lsm)) + continue; + if (lsm == NULL && display != LSMBLOB_INVALID && + display != hp->lsmid->slot) continue; return hp->hook.getprocattr(p, name, value); } return LSM_RET_DEFAULT(getprocattr); } +/** + * security_setprocattr - Set process attributes via /proc + * @lsm: name of module involved, or NULL + * @name: name of the attribute + * @value: value to set the attribute to + * @size: size of the value + * + * Set the process attribute for the specified security module + * to the specified value. Note that this can only be used to set + * the process attributes for the current, or "self" process. + * The /proc code has already done this check. + * + * Returns 0 on success, an appropriate code otherwise. + */ int security_setprocattr(const char *lsm, const char *name, void *value, size_t size) { struct security_hook_list *hp; + char *termed; + char *copy; + int *display = current->security; + int rc = -EINVAL; + int slot = 0; + + if (!strcmp(name, "display")) { + /* + * Change the "display" value only if all the security + * modules that support setting a procattr allow it. + * It is assumed that all such security modules will be + * cooperative. + */ + if (size == 0) + return -EINVAL; + + hlist_for_each_entry(hp, &security_hook_heads.setprocattr, + list) { + rc = hp->hook.setprocattr(name, value, size); + if (rc < 0) + return rc; + } + + rc = -EINVAL; + + copy = kmemdup_nul(value, size, GFP_KERNEL); + if (copy == NULL) + return -ENOMEM; + + termed = strsep(©, " \n"); + + for (slot = 0; slot < lsm_slot; slot++) + if (!strcmp(termed, lsm_slotlist[slot]->lsm)) { + *display = lsm_slotlist[slot]->slot; + rc = size; + break; + } + + kfree(termed); + return rc; + } hlist_for_each_entry(hp, &security_hook_heads.setprocattr, list) { - if (lsm != NULL && strcmp(lsm, hp->lsm)) + if (lsm != NULL && strcmp(lsm, hp->lsmid->lsm)) + continue; + if (lsm == NULL && *display != LSMBLOB_INVALID && + *display != hp->lsmid->slot) continue; return hp->hook.setprocattr(name, value, size); } @@ -2077,35 +2283,57 @@ int security_ismaclabel(const char *name) } EXPORT_SYMBOL(security_ismaclabel); -int security_secid_to_secctx(u32 secid, char **secdata, u32 *seclen) +int security_secid_to_secctx(struct lsmblob *blob, struct lsmcontext *cp) { struct security_hook_list *hp; - int rc; + int display = lsm_task_display(current); + + memset(cp, 0, sizeof(*cp)); - /* - * Currently, only one LSM can implement secid_to_secctx (i.e this - * LSM hook is not "stackable"). - */ hlist_for_each_entry(hp, &security_hook_heads.secid_to_secctx, list) { - rc = hp->hook.secid_to_secctx(secid, secdata, seclen); - if (rc != LSM_RET_DEFAULT(secid_to_secctx)) - return rc; + if (WARN_ON(hp->lsmid->slot < 0 || hp->lsmid->slot >= lsm_slot)) + continue; + if (display == LSMBLOB_INVALID || display == hp->lsmid->slot) { + cp->slot = hp->lsmid->slot; + return hp->hook.secid_to_secctx( + blob->secid[hp->lsmid->slot], + &cp->context, &cp->len); + } } return LSM_RET_DEFAULT(secid_to_secctx); } EXPORT_SYMBOL(security_secid_to_secctx); -int security_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid) +int security_secctx_to_secid(const char *secdata, u32 seclen, + struct lsmblob *blob) { - *secid = 0; - return call_int_hook(secctx_to_secid, 0, secdata, seclen, secid); + struct security_hook_list *hp; + int display = lsm_task_display(current); + + lsmblob_init(blob, 0); + hlist_for_each_entry(hp, &security_hook_heads.secctx_to_secid, list) { + if (WARN_ON(hp->lsmid->slot < 0 || hp->lsmid->slot >= lsm_slot)) + continue; + if (display == LSMBLOB_INVALID || display == hp->lsmid->slot) + return hp->hook.secctx_to_secid(secdata, seclen, + &blob->secid[hp->lsmid->slot]); + } + return 0; } EXPORT_SYMBOL(security_secctx_to_secid); -void security_release_secctx(char *secdata, u32 seclen) +void security_release_secctx(struct lsmcontext *cp) { - call_void_hook(release_secctx, secdata, seclen); + struct security_hook_list *hp; + + hlist_for_each_entry(hp, &security_hook_heads.release_secctx, list) + if (cp->slot == hp->lsmid->slot) { + hp->hook.release_secctx(cp->context, cp->len); + break; + } + + memset(cp, 0, sizeof(*cp)); } EXPORT_SYMBOL(security_release_secctx); @@ -2127,9 +2355,18 @@ int security_inode_setsecctx(struct dentry *dentry, void *ctx, u32 ctxlen) } EXPORT_SYMBOL(security_inode_setsecctx); -int security_inode_getsecctx(struct inode *inode, void **ctx, u32 *ctxlen) +int security_inode_getsecctx(struct inode *inode, struct lsmcontext *cp) { - return call_int_hook(inode_getsecctx, -EOPNOTSUPP, inode, ctx, ctxlen); + struct security_hook_list *hp; + + memset(cp, 0, sizeof(*cp)); + + hlist_for_each_entry(hp, &security_hook_heads.inode_getsecctx, list) { + cp->slot = hp->lsmid->slot; + return hp->hook.inode_getsecctx(inode, (void **)&cp->context, + &cp->len); + } + return -EOPNOTSUPP; } EXPORT_SYMBOL(security_inode_getsecctx); @@ -2246,25 +2483,53 @@ EXPORT_SYMBOL(security_sock_rcv_skb); int security_socket_getpeersec_stream(struct socket *sock, char __user *optval, int __user *optlen, unsigned len) { - return call_int_hook(socket_getpeersec_stream, -ENOPROTOOPT, sock, - optval, optlen, len); + int display = lsm_task_display(current); + struct security_hook_list *hp; + + hlist_for_each_entry(hp, &security_hook_heads.socket_getpeersec_stream, + list) + if (display == LSMBLOB_INVALID || display == hp->lsmid->slot) + return hp->hook.socket_getpeersec_stream(sock, optval, + optlen, len); + return -ENOPROTOOPT; } -int security_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb, u32 *secid) +int security_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb, + struct lsmblob *blob) { - return call_int_hook(socket_getpeersec_dgram, -ENOPROTOOPT, sock, - skb, secid); + struct security_hook_list *hp; + int rc = -ENOPROTOOPT; + + hlist_for_each_entry(hp, &security_hook_heads.socket_getpeersec_dgram, + list) { + if (WARN_ON(hp->lsmid->slot < 0 || hp->lsmid->slot >= lsm_slot)) + continue; + rc = hp->hook.socket_getpeersec_dgram(sock, skb, + &blob->secid[hp->lsmid->slot]); + if (rc != 0) + break; + } + return rc; } EXPORT_SYMBOL(security_socket_getpeersec_dgram); int security_sk_alloc(struct sock *sk, int family, gfp_t priority) { - return call_int_hook(sk_alloc_security, 0, sk, family, priority); + int rc = lsm_sock_alloc(sk, priority); + + if (unlikely(rc)) + return rc; + rc = call_int_hook(sk_alloc_security, 0, sk, family, priority); + if (unlikely(rc)) + security_sk_free(sk); + return rc; } void security_sk_free(struct sock *sk) { call_void_hook(sk_free_security, sk); + kfree(sk->sk_security); + sk->sk_security = NULL; } void security_sk_clone(const struct sock *sk, struct sock *newsk) @@ -2312,9 +2577,21 @@ void security_inet_conn_established(struct sock *sk, } EXPORT_SYMBOL(security_inet_conn_established); -int security_secmark_relabel_packet(u32 secid) +int security_secmark_relabel_packet(struct lsmblob *blob) { - return call_int_hook(secmark_relabel_packet, 0, secid); + struct security_hook_list *hp; + int rc = 0; + + hlist_for_each_entry(hp, &security_hook_heads.secmark_relabel_packet, + list) { + if (WARN_ON(hp->lsmid->slot < 0 || hp->lsmid->slot >= lsm_slot)) + continue; + rc = hp->hook.secmark_relabel_packet( + blob->secid[hp->lsmid->slot]); + if (rc != 0) + break; + } + return rc; } EXPORT_SYMBOL(security_secmark_relabel_packet); @@ -2543,7 +2820,24 @@ int security_key_getsecurity(struct key *key, char **_buffer) int security_audit_rule_init(u32 field, u32 op, char *rulestr, void **lsmrule) { - return call_int_hook(audit_rule_init, 0, field, op, rulestr, lsmrule); + struct security_hook_list *hp; + bool one_is_good = false; + int rc = 0; + int trc; + + hlist_for_each_entry(hp, &security_hook_heads.audit_rule_init, list) { + if (WARN_ON(hp->lsmid->slot < 0 || hp->lsmid->slot >= lsm_slot)) + continue; + trc = hp->hook.audit_rule_init(field, op, rulestr, + &lsmrule[hp->lsmid->slot]); + if (trc == 0) + one_is_good = true; + else + rc = trc; + } + if (one_is_good) + return 0; + return rc; } int security_audit_rule_known(struct audit_krule *krule) @@ -2551,14 +2845,37 @@ int security_audit_rule_known(struct audit_krule *krule) return call_int_hook(audit_rule_known, 0, krule); } -void security_audit_rule_free(void *lsmrule) +void security_audit_rule_free(void **lsmrule) { - call_void_hook(audit_rule_free, lsmrule); + struct security_hook_list *hp; + + hlist_for_each_entry(hp, &security_hook_heads.audit_rule_free, list) { + if (WARN_ON(hp->lsmid->slot < 0 || hp->lsmid->slot >= lsm_slot)) + continue; + if (lsmrule[hp->lsmid->slot] == NULL) + continue; + hp->hook.audit_rule_free(lsmrule[hp->lsmid->slot]); + } } -int security_audit_rule_match(u32 secid, u32 field, u32 op, void *lsmrule) +int security_audit_rule_match(struct lsmblob *blob, u32 field, u32 op, + void **lsmrule) { - return call_int_hook(audit_rule_match, 0, secid, field, op, lsmrule); + struct security_hook_list *hp; + int rc; + + hlist_for_each_entry(hp, &security_hook_heads.audit_rule_match, list) { + if (WARN_ON(hp->lsmid->slot < 0 || hp->lsmid->slot >= lsm_slot)) + continue; + if (lsmrule[hp->lsmid->slot] == NULL) + continue; + rc = hp->hook.audit_rule_match(blob->secid[hp->lsmid->slot], + field, op, + &lsmrule[hp->lsmid->slot]); + if (rc) + return rc; + } + return 0; } #endif /* CONFIG_AUDIT */