diff options
Diffstat (limited to 'security/keys/keyctl.c')
-rw-r--r-- | security/keys/keyctl.c | 77 |
1 files changed, 37 insertions, 40 deletions
diff --git a/security/keys/keyctl.c b/security/keys/keyctl.c index b61c063888b9..3bdc419b272f 100644 --- a/security/keys/keyctl.c +++ b/security/keys/keyctl.c @@ -84,7 +84,7 @@ SYSCALL_DEFINE5(add_key, const char __user *, _type, vm = false; if (_payload) { ret = -ENOMEM; - payload = kmalloc(plen, GFP_KERNEL); + payload = kmalloc(plen, GFP_KERNEL | __GFP_NOWARN); if (!payload) { if (plen <= PAGE_SIZE) goto error2; @@ -1110,7 +1110,7 @@ long keyctl_instantiate_key_iov(key_serial_t id, goto no_payload; ret = rw_copy_check_uvector(WRITE, _payload_iov, ioc, - ARRAY_SIZE(iovstack), iovstack, &iov, 1); + ARRAY_SIZE(iovstack), iovstack, &iov); if (ret < 0) return ret; if (ret == 0) @@ -1454,50 +1454,57 @@ long keyctl_get_security(key_serial_t keyid, */ long keyctl_session_to_parent(void) { -#ifdef TIF_NOTIFY_RESUME struct task_struct *me, *parent; const struct cred *mycred, *pcred; - struct cred *cred, *oldcred; + struct task_work *newwork, *oldwork; key_ref_t keyring_r; + struct cred *cred; int ret; keyring_r = lookup_user_key(KEY_SPEC_SESSION_KEYRING, 0, KEY_LINK); if (IS_ERR(keyring_r)) return PTR_ERR(keyring_r); + ret = -ENOMEM; + newwork = kmalloc(sizeof(struct task_work), GFP_KERNEL); + if (!newwork) + goto error_keyring; + /* our parent is going to need a new cred struct, a new tgcred struct * and new security data, so we allocate them here to prevent ENOMEM in * our parent */ - ret = -ENOMEM; cred = cred_alloc_blank(); if (!cred) - goto error_keyring; + goto error_newwork; cred->tgcred->session_keyring = key_ref_to_ptr(keyring_r); - keyring_r = NULL; + init_task_work(newwork, key_change_session_keyring, cred); me = current; rcu_read_lock(); write_lock_irq(&tasklist_lock); - parent = me->real_parent; ret = -EPERM; + oldwork = NULL; + parent = me->real_parent; /* the parent mustn't be init and mustn't be a kernel thread */ if (parent->pid <= 1 || !parent->mm) - goto not_permitted; + goto unlock; /* the parent must be single threaded */ if (!thread_group_empty(parent)) - goto not_permitted; + goto unlock; /* the parent and the child must have different session keyrings or * there's no point */ mycred = current_cred(); pcred = __task_cred(parent); if (mycred == pcred || - mycred->tgcred->session_keyring == pcred->tgcred->session_keyring) - goto already_same; + mycred->tgcred->session_keyring == pcred->tgcred->session_keyring) { + ret = 0; + goto unlock; + } /* the parent must have the same effective ownership and mustn't be * SUID/SGID */ @@ -1507,50 +1514,40 @@ long keyctl_session_to_parent(void) pcred->gid != mycred->egid || pcred->egid != mycred->egid || pcred->sgid != mycred->egid) - goto not_permitted; + goto unlock; /* the keyrings must have the same UID */ if ((pcred->tgcred->session_keyring && pcred->tgcred->session_keyring->uid != mycred->euid) || mycred->tgcred->session_keyring->uid != mycred->euid) - goto not_permitted; + goto unlock; - /* if there's an already pending keyring replacement, then we replace - * that */ - oldcred = parent->replacement_session_keyring; + /* cancel an already pending keyring replacement */ + oldwork = task_work_cancel(parent, key_change_session_keyring); /* the replacement session keyring is applied just prior to userspace * restarting */ - parent->replacement_session_keyring = cred; - cred = NULL; - set_ti_thread_flag(task_thread_info(parent), TIF_NOTIFY_RESUME); - - write_unlock_irq(&tasklist_lock); - rcu_read_unlock(); - if (oldcred) - put_cred(oldcred); - return 0; - -already_same: - ret = 0; -not_permitted: + ret = task_work_add(parent, newwork, true); + if (!ret) + newwork = NULL; +unlock: write_unlock_irq(&tasklist_lock); rcu_read_unlock(); - put_cred(cred); + if (oldwork) { + put_cred(oldwork->data); + kfree(oldwork); + } + if (newwork) { + put_cred(newwork->data); + kfree(newwork); + } return ret; +error_newwork: + kfree(newwork); error_keyring: key_ref_put(keyring_r); return ret; - -#else /* !TIF_NOTIFY_RESUME */ - /* - * To be removed when TIF_NOTIFY_RESUME has been implemented on - * m68k/xtensa - */ -#warning TIF_NOTIFY_RESUME not implemented - return -EOPNOTSUPP; -#endif /* !TIF_NOTIFY_RESUME */ } /* |