diff options
Diffstat (limited to 'security/selinux/hooks.c')
| -rw-r--r-- | security/selinux/hooks.c | 141 |
1 files changed, 115 insertions, 26 deletions
diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c index 644b17ec9e63..af2994adf9dd 100644 --- a/security/selinux/hooks.c +++ b/security/selinux/hooks.c @@ -484,6 +484,55 @@ static int selinux_is_sblabel_mnt(struct super_block *sb) } } +static int sb_check_xattr_support(struct super_block *sb) +{ + struct superblock_security_struct *sbsec = sb->s_security; + struct dentry *root = sb->s_root; + struct inode *root_inode = d_backing_inode(root); + u32 sid; + int rc; + + /* + * Make sure that the xattr handler exists and that no + * error other than -ENODATA is returned by getxattr on + * the root directory. -ENODATA is ok, as this may be + * the first boot of the SELinux kernel before we have + * assigned xattr values to the filesystem. + */ + if (!(root_inode->i_opflags & IOP_XATTR)) { + pr_warn("SELinux: (dev %s, type %s) has no xattr support\n", + sb->s_id, sb->s_type->name); + goto fallback; + } + + rc = __vfs_getxattr(root, root_inode, XATTR_NAME_SELINUX, NULL, 0); + if (rc < 0 && rc != -ENODATA) { + if (rc == -EOPNOTSUPP) { + pr_warn("SELinux: (dev %s, type %s) has no security xattr handler\n", + sb->s_id, sb->s_type->name); + goto fallback; + } else { + pr_warn("SELinux: (dev %s, type %s) getxattr errno %d\n", + sb->s_id, sb->s_type->name, -rc); + return rc; + } + } + return 0; + +fallback: + /* No xattr support - try to fallback to genfs if possible. */ + rc = security_genfs_sid(&selinux_state, sb->s_type->name, "/", + SECCLASS_DIR, &sid); + if (rc) + return -EOPNOTSUPP; + + pr_warn("SELinux: (dev %s, type %s) falling back to genfs\n", + sb->s_id, sb->s_type->name); + sbsec->behavior = SECURITY_FS_USE_GENFS; + sbsec->sid = sid; + return 0; +} + static int sb_finish_set_opts(struct super_block *sb) { struct superblock_security_struct *sbsec = sb->s_security; @@ -492,30 +541,9 @@ static int sb_finish_set_opts(struct super_block *sb) int rc = 0; if (sbsec->behavior == SECURITY_FS_USE_XATTR) { - /* Make sure that the xattr handler exists and that no - error other than -ENODATA is returned by getxattr on - the root directory. -ENODATA is ok, as this may be - the first boot of the SELinux kernel before we have - assigned xattr values to the filesystem. */ - if (!(root_inode->i_opflags & IOP_XATTR)) { - pr_warn("SELinux: (dev %s, type %s) has no " - "xattr support\n", sb->s_id, sb->s_type->name); - rc = -EOPNOTSUPP; - goto out; - } - - rc = __vfs_getxattr(root, root_inode, XATTR_NAME_SELINUX, NULL, 0); - if (rc < 0 && rc != -ENODATA) { - if (rc == -EOPNOTSUPP) - pr_warn("SELinux: (dev %s, type " - "%s) has no security xattr handler\n", - sb->s_id, sb->s_type->name); - else - pr_warn("SELinux: (dev %s, type " - "%s) getxattr errno %d\n", sb->s_id, - sb->s_type->name, -rc); - goto out; - } + rc = sb_check_xattr_support(sb); + if (rc) + return rc; } sbsec->flags |= SE_SBINITIALIZED; @@ -554,7 +582,6 @@ static int sb_finish_set_opts(struct super_block *sb) spin_lock(&sbsec->isec_lock); } spin_unlock(&sbsec->isec_lock); -out: return rc; } @@ -1120,7 +1147,8 @@ static inline u16 inode_mode_to_security_class(umode_t mode) static inline int default_protocol_stream(int protocol) { - return (protocol == IPPROTO_IP || protocol == IPPROTO_TCP); + return (protocol == IPPROTO_IP || protocol == IPPROTO_TCP || + protocol == IPPROTO_MPTCP); } static inline int default_protocol_dgram(int protocol) @@ -2934,6 +2962,62 @@ 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_initialized(&selinux_state))) + 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); @@ -3413,6 +3497,10 @@ static int selinux_inode_setsecurity(struct inode *inode, const char *name, static int selinux_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size) { const int len = sizeof(XATTR_NAME_SELINUX); + + if (!selinux_initialized(&selinux_state)) + return 0; + if (buffer && len <= buffer_size) memcpy(buffer, XATTR_NAME_SELINUX, len); return len; @@ -7000,6 +7088,7 @@ static struct security_hook_list selinux_hooks[] __lsm_ro_after_init = { 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), |