diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c index 51f4133f89e2..abe652fc6eba 100644 --- a/security/selinux/hooks.c +++ b/security/selinux/hooks.c @@ -2969,6 +2969,62 @@ static int selinux_inode_init_security(struct inode *inode, struct inode *dir, return 0; } +static int selinux_inode_init_security_anon(struct inode *inode, + const struct qstr *name, + const struct inode *context_inode) +{ + const struct task_security_struct *tsec = selinux_cred(current_cred()); + struct common_audit_data ad; + struct inode_security_struct *isec; + int rc; + + if (unlikely(!selinux_state.initialized)) + return 0; + + isec = selinux_inode(inode); + + /* + * We only get here once per ephemeral inode. The inode has + * been initialized via inode_alloc_security but is otherwise + * untouched. + */ + + if (context_inode) { + struct inode_security_struct *context_isec = + selinux_inode(context_inode); + if (context_isec->initialized != LABEL_INITIALIZED) { + pr_err("SELinux: context_inode is not initialized"); + return -EACCES; + } + + isec->sclass = context_isec->sclass; + isec->sid = context_isec->sid; + } else { + isec->sclass = SECCLASS_ANON_INODE; + rc = security_transition_sid( + &selinux_state, tsec->sid, tsec->sid, + isec->sclass, name, &isec->sid); + if (rc) + return rc; + } + + isec->initialized = LABEL_INITIALIZED; + /* + * Now that we've initialized security, check whether we're + * allowed to actually create this type of anonymous inode. + */ + + ad.type = LSM_AUDIT_DATA_INODE; + ad.u.inode = inode; + + return avc_has_perm(&selinux_state, + tsec->sid, + isec->sid, + isec->sclass, + FILE__CREATE, + &ad); +} + static int selinux_inode_create(struct inode *dir, struct dentry *dentry, umode_t mode) { return may_create(dir, dentry, SECCLASS_FILE); @@ -6999,6 +7055,7 @@ static struct security_hook_list selinux_hooks[] __lsm_ro_after_init = { LSM_HOOK_INIT(inode_alloc_security, selinux_inode_alloc_security), LSM_HOOK_INIT(inode_free_security, selinux_inode_free_security), LSM_HOOK_INIT(inode_init_security, selinux_inode_init_security), + LSM_HOOK_INIT(inode_init_security_anon, selinux_inode_init_security_anon), LSM_HOOK_INIT(inode_create, selinux_inode_create), LSM_HOOK_INIT(inode_link, selinux_inode_link), LSM_HOOK_INIT(inode_unlink, selinux_inode_unlink), diff --git a/security/selinux/include/classmap.h b/security/selinux/include/classmap.h index 74495cec84dc..542cbfc35787 100644 --- a/security/selinux/include/classmap.h +++ b/security/selinux/include/classmap.h @@ -247,7 +247,9 @@ struct security_class_mapping secclass_map[] = { { "xdp_socket", { COMMON_SOCK_PERMS, NULL } }, { "perf_event", - {"open", "cpu", "kernel", "tracepoint", "read", "write", NULL } }, + { "open", "cpu", "kernel", "tracepoint", "read", "write", NULL } }, + { "anon_inode", + { COMMON_FILE_PERMS, NULL } }, { NULL } };