whiterose

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commit 1f5a018c5b15c2e3e519ae8ca9bfb03a00384448
parent 40e196a906d969fd10d885c692d2674b3d657006
Author: Linus Torvalds <torvalds@linux-foundation.org>
Date:   Wed, 20 Feb 2019 09:09:33 -0800

Merge branch 'fixes-v5.1-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security

Pull keys fixes from James Morris:

 - Handle quotas better, allowing full quota to be reached.

 - Fix the creation of shortcuts in the assoc_array internal
   representation when the index key needs to be an exact multiple of
   the machine word size.

 - Fix a dependency loop between the request_key contruction record and
   the request_key authentication key. The construction record isn't
   really necessary and can be dispensed with.

 - Set the timestamp on a new key rather than leaving it as 0. This
   would ordinarily be fine - provided the system clock is never set to
   a time before 1970

* 'fixes-v5.1-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security:
  keys: Timestamp new keys
  keys: Fix dependency loop between construction record and auth key
  assoc_array: Fix shortcut creation
  KEYS: allow reaching the keys quotas exactly

Diffstat:
Mfs/nfs/nfs4idmap.c | 31+++++++++++++++++--------------
Ainclude/keys/request_key_auth-type.h | 36++++++++++++++++++++++++++++++++++++
Minclude/linux/key-type.h | 22++++++----------------
Mlib/assoc_array.c | 8+++++---
Msecurity/keys/internal.h | 13+------------
Msecurity/keys/key.c | 5+++--
Msecurity/keys/keyctl.c | 1+
Msecurity/keys/process_keys.c | 1+
Msecurity/keys/request_key.c | 72+++++++++++++++++++++++++++++-------------------------------------------
Msecurity/keys/request_key_auth.c | 16+++++++++-------
10 files changed, 108 insertions(+), 97 deletions(-)

diff --git a/fs/nfs/nfs4idmap.c b/fs/nfs/nfs4idmap.c @@ -44,6 +44,7 @@ #include <linux/keyctl.h> #include <linux/key-type.h> #include <keys/user-type.h> +#include <keys/request_key_auth-type.h> #include <linux/module.h> #include "internal.h" @@ -59,7 +60,7 @@ static struct key_type key_type_id_resolver_legacy; struct idmap_legacy_upcalldata { struct rpc_pipe_msg pipe_msg; struct idmap_msg idmap_msg; - struct key_construction *key_cons; + struct key *authkey; struct idmap *idmap; }; @@ -384,7 +385,7 @@ static const match_table_t nfs_idmap_tokens = { { Opt_find_err, NULL } }; -static int nfs_idmap_legacy_upcall(struct key_construction *, const char *, void *); +static int nfs_idmap_legacy_upcall(struct key *, void *); static ssize_t idmap_pipe_downcall(struct file *, const char __user *, size_t); static void idmap_release_pipe(struct inode *); @@ -549,11 +550,12 @@ nfs_idmap_prepare_pipe_upcall(struct idmap *idmap, static void nfs_idmap_complete_pipe_upcall_locked(struct idmap *idmap, int ret) { - struct key_construction *cons = idmap->idmap_upcall_data->key_cons; + struct key *authkey = idmap->idmap_upcall_data->authkey; kfree(idmap->idmap_upcall_data); idmap->idmap_upcall_data = NULL; - complete_request_key(cons, ret); + complete_request_key(authkey, ret); + key_put(authkey); } static void @@ -563,15 +565,14 @@ nfs_idmap_abort_pipe_upcall(struct idmap *idmap, int ret) nfs_idmap_complete_pipe_upcall_locked(idmap, ret); } -static int nfs_idmap_legacy_upcall(struct key_construction *cons, - const char *op, - void *aux) +static int nfs_idmap_legacy_upcall(struct key *authkey, void *aux) { struct idmap_legacy_upcalldata *data; + struct request_key_auth *rka = get_request_key_auth(authkey); struct rpc_pipe_msg *msg; struct idmap_msg *im; struct idmap *idmap = (struct idmap *)aux; - struct key *key = cons->key; + struct key *key = rka->target_key; int ret = -ENOKEY; if (!aux) @@ -586,7 +587,7 @@ static int nfs_idmap_legacy_upcall(struct key_construction *cons, msg = &data->pipe_msg; im = &data->idmap_msg; data->idmap = idmap; - data->key_cons = cons; + data->authkey = key_get(authkey); ret = nfs_idmap_prepare_message(key->description, idmap, im, msg); if (ret < 0) @@ -604,7 +605,7 @@ static int nfs_idmap_legacy_upcall(struct key_construction *cons, out2: kfree(data); out1: - complete_request_key(cons, ret); + complete_request_key(authkey, ret); return ret; } @@ -651,9 +652,10 @@ out: static ssize_t idmap_pipe_downcall(struct file *filp, const char __user *src, size_t mlen) { + struct request_key_auth *rka; struct rpc_inode *rpci = RPC_I(file_inode(filp)); struct idmap *idmap = (struct idmap *)rpci->private; - struct key_construction *cons; + struct key *authkey; struct idmap_msg im; size_t namelen_in; int ret = -ENOKEY; @@ -665,7 +667,8 @@ idmap_pipe_downcall(struct file *filp, const char __user *src, size_t mlen) if (idmap->idmap_upcall_data == NULL) goto out_noupcall; - cons = idmap->idmap_upcall_data->key_cons; + authkey = idmap->idmap_upcall_data->authkey; + rka = get_request_key_auth(authkey); if (mlen != sizeof(im)) { ret = -ENOSPC; @@ -690,9 +693,9 @@ idmap_pipe_downcall(struct file *filp, const char __user *src, size_t mlen) ret = nfs_idmap_read_and_verify_message(&im, &idmap->idmap_upcall_data->idmap_msg, - cons->key, cons->authkey); + rka->target_key, authkey); if (ret >= 0) { - key_set_timeout(cons->key, nfs_idmap_cache_timeout); + key_set_timeout(rka->target_key, nfs_idmap_cache_timeout); ret = mlen; } diff --git a/include/keys/request_key_auth-type.h b/include/keys/request_key_auth-type.h @@ -0,0 +1,36 @@ +/* request_key authorisation token key type + * + * Copyright (C) 2005 Red Hat, Inc. All Rights Reserved. + * Written by David Howells (dhowells@redhat.com) + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public Licence + * as published by the Free Software Foundation; either version + * 2 of the Licence, or (at your option) any later version. + */ + +#ifndef _KEYS_REQUEST_KEY_AUTH_TYPE_H +#define _KEYS_REQUEST_KEY_AUTH_TYPE_H + +#include <linux/key.h> + +/* + * Authorisation record for request_key(). + */ +struct request_key_auth { + struct key *target_key; + struct key *dest_keyring; + const struct cred *cred; + void *callout_info; + size_t callout_len; + pid_t pid; + char op[8]; +} __randomize_layout; + +static inline struct request_key_auth *get_request_key_auth(const struct key *key) +{ + return key->payload.data[0]; +} + + +#endif /* _KEYS_REQUEST_KEY_AUTH_TYPE_H */ diff --git a/include/linux/key-type.h b/include/linux/key-type.h @@ -21,15 +21,6 @@ struct kernel_pkey_query; struct kernel_pkey_params; /* - * key under-construction record - * - passed to the request_key actor if supplied - */ -struct key_construction { - struct key *key; /* key being constructed */ - struct key *authkey;/* authorisation for key being constructed */ -}; - -/* * Pre-parsed payload, used by key add, update and instantiate. * * This struct will be cleared and data and datalen will be set with the data @@ -50,8 +41,7 @@ struct key_preparsed_payload { time64_t expiry; /* Expiry time of key */ } __randomize_layout; -typedef int (*request_key_actor_t)(struct key_construction *key, - const char *op, void *aux); +typedef int (*request_key_actor_t)(struct key *auth_key, void *aux); /* * Preparsed matching criterion. @@ -181,20 +171,20 @@ extern int key_instantiate_and_link(struct key *key, const void *data, size_t datalen, struct key *keyring, - struct key *instkey); + struct key *authkey); extern int key_reject_and_link(struct key *key, unsigned timeout, unsigned error, struct key *keyring, - struct key *instkey); -extern void complete_request_key(struct key_construction *cons, int error); + struct key *authkey); +extern void complete_request_key(struct key *authkey, int error); static inline int key_negate_and_link(struct key *key, unsigned timeout, struct key *keyring, - struct key *instkey) + struct key *authkey) { - return key_reject_and_link(key, timeout, ENOKEY, keyring, instkey); + return key_reject_and_link(key, timeout, ENOKEY, keyring, authkey); } extern int generic_key_instantiate(struct key *key, struct key_preparsed_payload *prep); diff --git a/lib/assoc_array.c b/lib/assoc_array.c @@ -768,9 +768,11 @@ all_leaves_cluster_together: new_s0->index_key[i] = ops->get_key_chunk(index_key, i * ASSOC_ARRAY_KEY_CHUNK_SIZE); - blank = ULONG_MAX << (level & ASSOC_ARRAY_KEY_CHUNK_MASK); - pr_devel("blank off [%zu] %d: %lx\n", keylen - 1, level, blank); - new_s0->index_key[keylen - 1] &= ~blank; + if (level & ASSOC_ARRAY_KEY_CHUNK_MASK) { + blank = ULONG_MAX << (level & ASSOC_ARRAY_KEY_CHUNK_MASK); + pr_devel("blank off [%zu] %d: %lx\n", keylen - 1, level, blank); + new_s0->index_key[keylen - 1] &= ~blank; + } /* This now reduces to a node splitting exercise for which we'll need * to regenerate the disparity table. diff --git a/security/keys/internal.h b/security/keys/internal.h @@ -186,20 +186,9 @@ static inline int key_permission(const key_ref_t key_ref, unsigned perm) return key_task_permission(key_ref, current_cred(), perm); } -/* - * Authorisation record for request_key(). - */ -struct request_key_auth { - struct key *target_key; - struct key *dest_keyring; - const struct cred *cred; - void *callout_info; - size_t callout_len; - pid_t pid; -} __randomize_layout; - extern struct key_type key_type_request_key_auth; extern struct key *request_key_auth_new(struct key *target, + const char *op, const void *callout_info, size_t callout_len, struct key *dest_keyring); diff --git a/security/keys/key.c b/security/keys/key.c @@ -265,8 +265,8 @@ struct key *key_alloc(struct key_type *type, const char *desc, spin_lock(&user->lock); if (!(flags & KEY_ALLOC_QUOTA_OVERRUN)) { - if (user->qnkeys + 1 >= maxkeys || - user->qnbytes + quotalen >= maxbytes || + if (user->qnkeys + 1 > maxkeys || + user->qnbytes + quotalen > maxbytes || user->qnbytes + quotalen < user->qnbytes) goto no_quota; } @@ -297,6 +297,7 @@ struct key *key_alloc(struct key_type *type, const char *desc, key->gid = gid; key->perm = perm; key->restrict_link = restrict_link; + key->last_used_at = ktime_get_real_seconds(); if (!(flags & KEY_ALLOC_NOT_IN_QUOTA)) key->flags |= 1 << KEY_FLAG_IN_QUOTA; diff --git a/security/keys/keyctl.c b/security/keys/keyctl.c @@ -25,6 +25,7 @@ #include <linux/security.h> #include <linux/uio.h> #include <linux/uaccess.h> +#include <keys/request_key_auth-type.h> #include "internal.h" #define KEY_MAX_DESC_SIZE 4096 diff --git a/security/keys/process_keys.c b/security/keys/process_keys.c @@ -19,6 +19,7 @@ #include <linux/security.h> #include <linux/user_namespace.h> #include <linux/uaccess.h> +#include <keys/request_key_auth-type.h> #include "internal.h" /* Session keyring create vs join semaphore */ diff --git a/security/keys/request_key.c b/security/keys/request_key.c @@ -18,31 +18,30 @@ #include <linux/keyctl.h> #include <linux/slab.h> #include "internal.h" +#include <keys/request_key_auth-type.h> #define key_negative_timeout 60 /* default timeout on a negative key's existence */ /** * complete_request_key - Complete the construction of a key. - * @cons: The key construction record. + * @auth_key: The authorisation key. * @error: The success or failute of the construction. * * Complete the attempt to construct a key. The key will be negated * if an error is indicated. The authorisation key will be revoked * unconditionally. */ -void complete_request_key(struct key_construction *cons, int error) +void complete_request_key(struct key *authkey, int error) { - kenter("{%d,%d},%d", cons->key->serial, cons->authkey->serial, error); + struct request_key_auth *rka = get_request_key_auth(authkey); + struct key *key = rka->target_key; + + kenter("%d{%d},%d", authkey->serial, key->serial, error); if (error < 0) - key_negate_and_link(cons->key, key_negative_timeout, NULL, - cons->authkey); + key_negate_and_link(key, key_negative_timeout, NULL, authkey); else - key_revoke(cons->authkey); - - key_put(cons->key); - key_put(cons->authkey); - kfree(cons); + key_revoke(authkey); } EXPORT_SYMBOL(complete_request_key); @@ -91,21 +90,19 @@ static int call_usermodehelper_keys(const char *path, char **argv, char **envp, * Request userspace finish the construction of a key * - execute "/sbin/request-key <op> <key> <uid> <gid> <keyring> <keyring> <keyring>" */ -static int call_sbin_request_key(struct key_construction *cons, - const char *op, - void *aux) +static int call_sbin_request_key(struct key *authkey, void *aux) { static char const request_key[] = "/sbin/request-key"; + struct request_key_auth *rka = get_request_key_auth(authkey); const struct cred *cred = current_cred(); key_serial_t prkey, sskey; - struct key *key = cons->key, *authkey = cons->authkey, *keyring, - *session; + struct key *key = rka->target_key, *keyring, *session; char *argv[9], *envp[3], uid_str[12], gid_str[12]; char key_str[12], keyring_str[3][12]; char desc[20]; int ret, i; - kenter("{%d},{%d},%s", key->serial, authkey->serial, op); + kenter("{%d},{%d},%s", key->serial, authkey->serial, rka->op); ret = install_user_keyrings(); if (ret < 0) @@ -163,7 +160,7 @@ static int call_sbin_request_key(struct key_construction *cons, /* set up the argument list */ i = 0; argv[i++] = (char *)request_key; - argv[i++] = (char *) op; + argv[i++] = (char *)rka->op; argv[i++] = key_str; argv[i++] = uid_str; argv[i++] = gid_str; @@ -191,7 +188,7 @@ error_link: key_put(keyring); error_alloc: - complete_request_key(cons, ret); + complete_request_key(authkey, ret); kleave(" = %d", ret); return ret; } @@ -205,42 +202,31 @@ static int construct_key(struct key *key, const void *callout_info, size_t callout_len, void *aux, struct key *dest_keyring) { - struct key_construction *cons; request_key_actor_t actor; struct key *authkey; int ret; kenter("%d,%p,%zu,%p", key->serial, callout_info, callout_len, aux); - cons = kmalloc(sizeof(*cons), GFP_KERNEL); - if (!cons) - return -ENOMEM; - /* allocate an authorisation key */ - authkey = request_key_auth_new(key, callout_info, callout_len, + authkey = request_key_auth_new(key, "create", callout_info, callout_len, dest_keyring); - if (IS_ERR(authkey)) { - kfree(cons); - ret = PTR_ERR(authkey); - authkey = NULL; - } else { - cons->authkey = key_get(authkey); - cons->key = key_get(key); + if (IS_ERR(authkey)) + return PTR_ERR(authkey); - /* make the call */ - actor = call_sbin_request_key; - if (key->type->request_key) - actor = key->type->request_key; + /* Make the call */ + actor = call_sbin_request_key; + if (key->type->request_key) + actor = key->type->request_key; - ret = actor(cons, "create", aux); + ret = actor(authkey, aux); - /* check that the actor called complete_request_key() prior to - * returning an error */ - WARN_ON(ret < 0 && - !test_bit(KEY_FLAG_REVOKED, &authkey->flags)); - key_put(authkey); - } + /* check that the actor called complete_request_key() prior to + * returning an error */ + WARN_ON(ret < 0 && + !test_bit(KEY_FLAG_REVOKED, &authkey->flags)); + key_put(authkey); kleave(" = %d", ret); return ret; } @@ -275,7 +261,7 @@ static int construct_get_dest_keyring(struct key **_dest_keyring) if (cred->request_key_auth) { authkey = cred->request_key_auth; down_read(&authkey->sem); - rka = authkey->payload.data[0]; + rka = get_request_key_auth(authkey); if (!test_bit(KEY_FLAG_REVOKED, &authkey->flags)) dest_keyring = diff --git a/security/keys/request_key_auth.c b/security/keys/request_key_auth.c @@ -17,7 +17,7 @@ #include <linux/slab.h> #include <linux/uaccess.h> #include "internal.h" -#include <keys/user-type.h> +#include <keys/request_key_auth-type.h> static int request_key_auth_preparse(struct key_preparsed_payload *); static void request_key_auth_free_preparse(struct key_preparsed_payload *); @@ -68,7 +68,7 @@ static int request_key_auth_instantiate(struct key *key, static void request_key_auth_describe(const struct key *key, struct seq_file *m) { - struct request_key_auth *rka = key->payload.data[0]; + struct request_key_auth *rka = get_request_key_auth(key); seq_puts(m, "key:"); seq_puts(m, key->description); @@ -83,7 +83,7 @@ static void request_key_auth_describe(const struct key *key, static long request_key_auth_read(const struct key *key, char __user *buffer, size_t buflen) { - struct request_key_auth *rka = key->payload.data[0]; + struct request_key_auth *rka = get_request_key_auth(key); size_t datalen; long ret; @@ -109,7 +109,7 @@ static long request_key_auth_read(const struct key *key, */ static void request_key_auth_revoke(struct key *key) { - struct request_key_auth *rka = key->payload.data[0]; + struct request_key_auth *rka = get_request_key_auth(key); kenter("{%d}", key->serial); @@ -136,7 +136,7 @@ static void free_request_key_auth(struct request_key_auth *rka) */ static void request_key_auth_destroy(struct key *key) { - struct request_key_auth *rka = key->payload.data[0]; + struct request_key_auth *rka = get_request_key_auth(key); kenter("{%d}", key->serial); @@ -147,8 +147,9 @@ static void request_key_auth_destroy(struct key *key) * Create an authorisation token for /sbin/request-key or whoever to gain * access to the caller's security data. */ -struct key *request_key_auth_new(struct key *target, const void *callout_info, - size_t callout_len, struct key *dest_keyring) +struct key *request_key_auth_new(struct key *target, const char *op, + const void *callout_info, size_t callout_len, + struct key *dest_keyring) { struct request_key_auth *rka, *irka; const struct cred *cred = current->cred; @@ -166,6 +167,7 @@ struct key *request_key_auth_new(struct key *target, const void *callout_info, if (!rka->callout_info) goto error_free_rka; rka->callout_len = callout_len; + strlcpy(rka->op, op, sizeof(rka->op)); /* see if the calling process is already servicing the key request of * another process */