.. | .. |
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| 1 | +// SPDX-License-Identifier: GPL-2.0-or-later |
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1 | 2 | /* Manage a process's keyrings |
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2 | 3 | * |
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3 | 4 | * Copyright (C) 2004-2005, 2008 Red Hat, Inc. All Rights Reserved. |
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4 | 5 | * Written by David Howells (dhowells@redhat.com) |
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5 | | - * |
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6 | | - * This program is free software; you can redistribute it and/or |
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7 | | - * modify it under the terms of the GNU General Public License |
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8 | | - * as published by the Free Software Foundation; either version |
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9 | | - * 2 of the License, or (at your option) any later version. |
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10 | 6 | */ |
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11 | 7 | |
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12 | | -#include <linux/module.h> |
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13 | 8 | #include <linux/init.h> |
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14 | 9 | #include <linux/sched.h> |
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15 | 10 | #include <linux/sched/user.h> |
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.. | .. |
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20 | 15 | #include <linux/security.h> |
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21 | 16 | #include <linux/user_namespace.h> |
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22 | 17 | #include <linux/uaccess.h> |
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| 18 | +#include <linux/init_task.h> |
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23 | 19 | #include <keys/request_key_auth-type.h> |
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24 | 20 | #include "internal.h" |
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25 | 21 | |
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26 | 22 | /* Session keyring create vs join semaphore */ |
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27 | 23 | static DEFINE_MUTEX(key_session_mutex); |
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28 | | - |
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29 | | -/* User keyring creation semaphore */ |
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30 | | -static DEFINE_MUTEX(key_user_keyring_mutex); |
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31 | 24 | |
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32 | 25 | /* The root user's tracking struct */ |
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33 | 26 | struct key_user root_key_user = { |
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.. | .. |
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40 | 33 | }; |
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41 | 34 | |
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42 | 35 | /* |
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43 | | - * Install the user and user session keyrings for the current process's UID. |
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| 36 | + * Get or create a user register keyring. |
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44 | 37 | */ |
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45 | | -int install_user_keyrings(void) |
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| 38 | +static struct key *get_user_register(struct user_namespace *user_ns) |
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46 | 39 | { |
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47 | | - struct user_struct *user; |
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48 | | - const struct cred *cred; |
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49 | | - struct key *uid_keyring, *session_keyring; |
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| 40 | + struct key *reg_keyring = READ_ONCE(user_ns->user_keyring_register); |
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| 41 | + |
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| 42 | + if (reg_keyring) |
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| 43 | + return reg_keyring; |
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| 44 | + |
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| 45 | + down_write(&user_ns->keyring_sem); |
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| 46 | + |
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| 47 | + /* Make sure there's a register keyring. It gets owned by the |
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| 48 | + * user_namespace's owner. |
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| 49 | + */ |
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| 50 | + reg_keyring = user_ns->user_keyring_register; |
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| 51 | + if (!reg_keyring) { |
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| 52 | + reg_keyring = keyring_alloc(".user_reg", |
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| 53 | + user_ns->owner, INVALID_GID, |
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| 54 | + &init_cred, |
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| 55 | + KEY_POS_WRITE | KEY_POS_SEARCH | |
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| 56 | + KEY_USR_VIEW | KEY_USR_READ, |
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| 57 | + 0, |
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| 58 | + NULL, NULL); |
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| 59 | + if (!IS_ERR(reg_keyring)) |
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| 60 | + smp_store_release(&user_ns->user_keyring_register, |
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| 61 | + reg_keyring); |
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| 62 | + } |
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| 63 | + |
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| 64 | + up_write(&user_ns->keyring_sem); |
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| 65 | + |
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| 66 | + /* We don't return a ref since the keyring is pinned by the user_ns */ |
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| 67 | + return reg_keyring; |
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| 68 | +} |
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| 69 | + |
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| 70 | +/* |
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| 71 | + * Look up the user and user session keyrings for the current process's UID, |
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| 72 | + * creating them if they don't exist. |
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| 73 | + */ |
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| 74 | +int look_up_user_keyrings(struct key **_user_keyring, |
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| 75 | + struct key **_user_session_keyring) |
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| 76 | +{ |
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| 77 | + const struct cred *cred = current_cred(); |
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| 78 | + struct user_namespace *user_ns = current_user_ns(); |
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| 79 | + struct key *reg_keyring, *uid_keyring, *session_keyring; |
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50 | 80 | key_perm_t user_keyring_perm; |
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| 81 | + key_ref_t uid_keyring_r, session_keyring_r; |
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| 82 | + uid_t uid = from_kuid(user_ns, cred->user->uid); |
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51 | 83 | char buf[20]; |
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52 | 84 | int ret; |
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53 | | - uid_t uid; |
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54 | 85 | |
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55 | 86 | user_keyring_perm = (KEY_POS_ALL & ~KEY_POS_SETATTR) | KEY_USR_ALL; |
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56 | | - cred = current_cred(); |
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57 | | - user = cred->user; |
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58 | | - uid = from_kuid(cred->user_ns, user->uid); |
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59 | 87 | |
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60 | | - kenter("%p{%u}", user, uid); |
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| 88 | + kenter("%u", uid); |
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61 | 89 | |
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62 | | - if (user->uid_keyring && user->session_keyring) { |
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63 | | - kleave(" = 0 [exist]"); |
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64 | | - return 0; |
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65 | | - } |
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| 90 | + reg_keyring = get_user_register(user_ns); |
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| 91 | + if (IS_ERR(reg_keyring)) |
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| 92 | + return PTR_ERR(reg_keyring); |
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66 | 93 | |
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67 | | - mutex_lock(&key_user_keyring_mutex); |
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| 94 | + down_write(&user_ns->keyring_sem); |
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68 | 95 | ret = 0; |
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69 | 96 | |
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70 | | - if (!user->uid_keyring) { |
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71 | | - /* get the UID-specific keyring |
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72 | | - * - there may be one in existence already as it may have been |
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73 | | - * pinned by a session, but the user_struct pointing to it |
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74 | | - * may have been destroyed by setuid */ |
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75 | | - sprintf(buf, "_uid.%u", uid); |
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76 | | - |
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77 | | - uid_keyring = find_keyring_by_name(buf, true); |
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| 97 | + /* Get the user keyring. Note that there may be one in existence |
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| 98 | + * already as it may have been pinned by a session, but the user_struct |
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| 99 | + * pointing to it may have been destroyed by setuid. |
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| 100 | + */ |
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| 101 | + snprintf(buf, sizeof(buf), "_uid.%u", uid); |
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| 102 | + uid_keyring_r = keyring_search(make_key_ref(reg_keyring, true), |
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| 103 | + &key_type_keyring, buf, false); |
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| 104 | + kdebug("_uid %p", uid_keyring_r); |
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| 105 | + if (uid_keyring_r == ERR_PTR(-EAGAIN)) { |
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| 106 | + uid_keyring = keyring_alloc(buf, cred->user->uid, INVALID_GID, |
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| 107 | + cred, user_keyring_perm, |
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| 108 | + KEY_ALLOC_UID_KEYRING | |
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| 109 | + KEY_ALLOC_IN_QUOTA, |
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| 110 | + NULL, reg_keyring); |
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78 | 111 | if (IS_ERR(uid_keyring)) { |
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79 | | - uid_keyring = keyring_alloc(buf, user->uid, INVALID_GID, |
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80 | | - cred, user_keyring_perm, |
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81 | | - KEY_ALLOC_UID_KEYRING | |
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82 | | - KEY_ALLOC_IN_QUOTA, |
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83 | | - NULL, NULL); |
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84 | | - if (IS_ERR(uid_keyring)) { |
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85 | | - ret = PTR_ERR(uid_keyring); |
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86 | | - goto error; |
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87 | | - } |
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| 112 | + ret = PTR_ERR(uid_keyring); |
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| 113 | + goto error; |
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88 | 114 | } |
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89 | | - |
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90 | | - /* get a default session keyring (which might also exist |
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91 | | - * already) */ |
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92 | | - sprintf(buf, "_uid_ses.%u", uid); |
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93 | | - |
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94 | | - session_keyring = find_keyring_by_name(buf, true); |
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95 | | - if (IS_ERR(session_keyring)) { |
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96 | | - session_keyring = |
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97 | | - keyring_alloc(buf, user->uid, INVALID_GID, |
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98 | | - cred, user_keyring_perm, |
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99 | | - KEY_ALLOC_UID_KEYRING | |
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100 | | - KEY_ALLOC_IN_QUOTA, |
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101 | | - NULL, NULL); |
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102 | | - if (IS_ERR(session_keyring)) { |
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103 | | - ret = PTR_ERR(session_keyring); |
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104 | | - goto error_release; |
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105 | | - } |
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106 | | - |
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107 | | - /* we install a link from the user session keyring to |
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108 | | - * the user keyring */ |
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109 | | - ret = key_link(session_keyring, uid_keyring); |
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110 | | - if (ret < 0) |
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111 | | - goto error_release_both; |
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112 | | - } |
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113 | | - |
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114 | | - /* install the keyrings */ |
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115 | | - user->uid_keyring = uid_keyring; |
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116 | | - user->session_keyring = session_keyring; |
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| 115 | + } else if (IS_ERR(uid_keyring_r)) { |
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| 116 | + ret = PTR_ERR(uid_keyring_r); |
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| 117 | + goto error; |
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| 118 | + } else { |
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| 119 | + uid_keyring = key_ref_to_ptr(uid_keyring_r); |
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117 | 120 | } |
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118 | 121 | |
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119 | | - mutex_unlock(&key_user_keyring_mutex); |
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| 122 | + /* Get a default session keyring (which might also exist already) */ |
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| 123 | + snprintf(buf, sizeof(buf), "_uid_ses.%u", uid); |
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| 124 | + session_keyring_r = keyring_search(make_key_ref(reg_keyring, true), |
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| 125 | + &key_type_keyring, buf, false); |
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| 126 | + kdebug("_uid_ses %p", session_keyring_r); |
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| 127 | + if (session_keyring_r == ERR_PTR(-EAGAIN)) { |
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| 128 | + session_keyring = keyring_alloc(buf, cred->user->uid, INVALID_GID, |
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| 129 | + cred, user_keyring_perm, |
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| 130 | + KEY_ALLOC_UID_KEYRING | |
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| 131 | + KEY_ALLOC_IN_QUOTA, |
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| 132 | + NULL, NULL); |
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| 133 | + if (IS_ERR(session_keyring)) { |
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| 134 | + ret = PTR_ERR(session_keyring); |
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| 135 | + goto error_release; |
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| 136 | + } |
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| 137 | + |
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| 138 | + /* We install a link from the user session keyring to |
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| 139 | + * the user keyring. |
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| 140 | + */ |
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| 141 | + ret = key_link(session_keyring, uid_keyring); |
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| 142 | + if (ret < 0) |
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| 143 | + goto error_release_session; |
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| 144 | + |
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| 145 | + /* And only then link the user-session keyring to the |
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| 146 | + * register. |
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| 147 | + */ |
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| 148 | + ret = key_link(reg_keyring, session_keyring); |
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| 149 | + if (ret < 0) |
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| 150 | + goto error_release_session; |
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| 151 | + } else if (IS_ERR(session_keyring_r)) { |
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| 152 | + ret = PTR_ERR(session_keyring_r); |
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| 153 | + goto error_release; |
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| 154 | + } else { |
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| 155 | + session_keyring = key_ref_to_ptr(session_keyring_r); |
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| 156 | + } |
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| 157 | + |
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| 158 | + up_write(&user_ns->keyring_sem); |
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| 159 | + |
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| 160 | + if (_user_session_keyring) |
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| 161 | + *_user_session_keyring = session_keyring; |
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| 162 | + else |
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| 163 | + key_put(session_keyring); |
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| 164 | + if (_user_keyring) |
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| 165 | + *_user_keyring = uid_keyring; |
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| 166 | + else |
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| 167 | + key_put(uid_keyring); |
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120 | 168 | kleave(" = 0"); |
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121 | 169 | return 0; |
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122 | 170 | |
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123 | | -error_release_both: |
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| 171 | +error_release_session: |
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124 | 172 | key_put(session_keyring); |
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125 | 173 | error_release: |
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126 | 174 | key_put(uid_keyring); |
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127 | 175 | error: |
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128 | | - mutex_unlock(&key_user_keyring_mutex); |
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| 176 | + up_write(&user_ns->keyring_sem); |
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129 | 177 | kleave(" = %d", ret); |
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130 | 178 | return ret; |
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| 179 | +} |
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| 180 | + |
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| 181 | +/* |
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| 182 | + * Get the user session keyring if it exists, but don't create it if it |
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| 183 | + * doesn't. |
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| 184 | + */ |
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| 185 | +struct key *get_user_session_keyring_rcu(const struct cred *cred) |
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| 186 | +{ |
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| 187 | + struct key *reg_keyring = READ_ONCE(cred->user_ns->user_keyring_register); |
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| 188 | + key_ref_t session_keyring_r; |
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| 189 | + char buf[20]; |
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| 190 | + |
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| 191 | + struct keyring_search_context ctx = { |
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| 192 | + .index_key.type = &key_type_keyring, |
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| 193 | + .index_key.description = buf, |
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| 194 | + .cred = cred, |
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| 195 | + .match_data.cmp = key_default_cmp, |
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| 196 | + .match_data.raw_data = buf, |
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| 197 | + .match_data.lookup_type = KEYRING_SEARCH_LOOKUP_DIRECT, |
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| 198 | + .flags = KEYRING_SEARCH_DO_STATE_CHECK, |
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| 199 | + }; |
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| 200 | + |
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| 201 | + if (!reg_keyring) |
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| 202 | + return NULL; |
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| 203 | + |
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| 204 | + ctx.index_key.desc_len = snprintf(buf, sizeof(buf), "_uid_ses.%u", |
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| 205 | + from_kuid(cred->user_ns, |
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| 206 | + cred->user->uid)); |
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| 207 | + |
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| 208 | + session_keyring_r = keyring_search_rcu(make_key_ref(reg_keyring, true), |
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| 209 | + &ctx); |
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| 210 | + if (IS_ERR(session_keyring_r)) |
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| 211 | + return NULL; |
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| 212 | + return key_ref_to_ptr(session_keyring_r); |
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131 | 213 | } |
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132 | 214 | |
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133 | 215 | /* |
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.. | .. |
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228 | 310 | * Install the given keyring as the session keyring of the given credentials |
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229 | 311 | * struct, replacing the existing one if any. If the given keyring is NULL, |
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230 | 312 | * then install a new anonymous session keyring. |
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| 313 | + * @cred can not be in use by any task yet. |
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231 | 314 | * |
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232 | 315 | * Return: 0 on success; -errno on failure. |
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233 | 316 | */ |
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.. | .. |
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255 | 338 | |
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256 | 339 | /* install the keyring */ |
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257 | 340 | old = cred->session_keyring; |
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258 | | - rcu_assign_pointer(cred->session_keyring, keyring); |
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| 341 | + cred->session_keyring = keyring; |
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259 | 342 | |
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260 | 343 | if (old) |
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261 | 344 | key_put(old); |
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.. | .. |
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291 | 374 | /* |
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292 | 375 | * Handle the fsuid changing. |
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293 | 376 | */ |
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294 | | -void key_fsuid_changed(struct task_struct *tsk) |
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| 377 | +void key_fsuid_changed(struct cred *new_cred) |
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295 | 378 | { |
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296 | 379 | /* update the ownership of the thread keyring */ |
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297 | | - BUG_ON(!tsk->cred); |
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298 | | - if (tsk->cred->thread_keyring) { |
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299 | | - down_write(&tsk->cred->thread_keyring->sem); |
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300 | | - tsk->cred->thread_keyring->uid = tsk->cred->fsuid; |
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301 | | - up_write(&tsk->cred->thread_keyring->sem); |
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| 380 | + if (new_cred->thread_keyring) { |
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| 381 | + down_write(&new_cred->thread_keyring->sem); |
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| 382 | + new_cred->thread_keyring->uid = new_cred->fsuid; |
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| 383 | + up_write(&new_cred->thread_keyring->sem); |
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302 | 384 | } |
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303 | 385 | } |
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304 | 386 | |
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305 | 387 | /* |
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306 | 388 | * Handle the fsgid changing. |
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307 | 389 | */ |
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308 | | -void key_fsgid_changed(struct task_struct *tsk) |
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| 390 | +void key_fsgid_changed(struct cred *new_cred) |
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309 | 391 | { |
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310 | 392 | /* update the ownership of the thread keyring */ |
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311 | | - BUG_ON(!tsk->cred); |
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312 | | - if (tsk->cred->thread_keyring) { |
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313 | | - down_write(&tsk->cred->thread_keyring->sem); |
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314 | | - tsk->cred->thread_keyring->gid = tsk->cred->fsgid; |
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315 | | - up_write(&tsk->cred->thread_keyring->sem); |
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| 393 | + if (new_cred->thread_keyring) { |
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| 394 | + down_write(&new_cred->thread_keyring->sem); |
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| 395 | + new_cred->thread_keyring->gid = new_cred->fsgid; |
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| 396 | + up_write(&new_cred->thread_keyring->sem); |
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316 | 397 | } |
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317 | 398 | } |
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318 | 399 | |
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319 | 400 | /* |
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320 | 401 | * Search the process keyrings attached to the supplied cred for the first |
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321 | | - * matching key. |
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| 402 | + * matching key under RCU conditions (the caller must be holding the RCU read |
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| 403 | + * lock). |
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322 | 404 | * |
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323 | 405 | * The search criteria are the type and the match function. The description is |
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324 | 406 | * given to the match function as a parameter, but doesn't otherwise influence |
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.. | .. |
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337 | 419 | * In the case of a successful return, the possession attribute is set on the |
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338 | 420 | * returned key reference. |
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339 | 421 | */ |
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340 | | -key_ref_t search_my_process_keyrings(struct keyring_search_context *ctx) |
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| 422 | +key_ref_t search_cred_keyrings_rcu(struct keyring_search_context *ctx) |
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341 | 423 | { |
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| 424 | + struct key *user_session; |
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342 | 425 | key_ref_t key_ref, ret, err; |
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| 426 | + const struct cred *cred = ctx->cred; |
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343 | 427 | |
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344 | 428 | /* we want to return -EAGAIN or -ENOKEY if any of the keyrings were |
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345 | 429 | * searchable, but we failed to find a key or we found a negative key; |
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.. | .. |
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353 | 437 | err = ERR_PTR(-EAGAIN); |
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354 | 438 | |
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355 | 439 | /* search the thread keyring first */ |
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356 | | - if (ctx->cred->thread_keyring) { |
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357 | | - key_ref = keyring_search_aux( |
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358 | | - make_key_ref(ctx->cred->thread_keyring, 1), ctx); |
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| 440 | + if (cred->thread_keyring) { |
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| 441 | + key_ref = keyring_search_rcu( |
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| 442 | + make_key_ref(cred->thread_keyring, 1), ctx); |
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359 | 443 | if (!IS_ERR(key_ref)) |
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360 | 444 | goto found; |
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361 | 445 | |
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.. | .. |
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371 | 455 | } |
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372 | 456 | |
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373 | 457 | /* search the process keyring second */ |
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374 | | - if (ctx->cred->process_keyring) { |
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375 | | - key_ref = keyring_search_aux( |
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376 | | - make_key_ref(ctx->cred->process_keyring, 1), ctx); |
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| 458 | + if (cred->process_keyring) { |
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| 459 | + key_ref = keyring_search_rcu( |
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| 460 | + make_key_ref(cred->process_keyring, 1), ctx); |
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377 | 461 | if (!IS_ERR(key_ref)) |
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378 | 462 | goto found; |
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379 | 463 | |
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.. | .. |
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381 | 465 | case -EAGAIN: /* no key */ |
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382 | 466 | if (ret) |
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383 | 467 | break; |
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| 468 | + fallthrough; |
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384 | 469 | case -ENOKEY: /* negative key */ |
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385 | 470 | ret = key_ref; |
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386 | 471 | break; |
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.. | .. |
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391 | 476 | } |
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392 | 477 | |
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393 | 478 | /* search the session keyring */ |
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394 | | - if (ctx->cred->session_keyring) { |
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395 | | - rcu_read_lock(); |
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396 | | - key_ref = keyring_search_aux( |
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397 | | - make_key_ref(rcu_dereference(ctx->cred->session_keyring), 1), |
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398 | | - ctx); |
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399 | | - rcu_read_unlock(); |
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| 479 | + if (cred->session_keyring) { |
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| 480 | + key_ref = keyring_search_rcu( |
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| 481 | + make_key_ref(cred->session_keyring, 1), ctx); |
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400 | 482 | |
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401 | 483 | if (!IS_ERR(key_ref)) |
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402 | 484 | goto found; |
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.. | .. |
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405 | 487 | case -EAGAIN: /* no key */ |
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406 | 488 | if (ret) |
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407 | 489 | break; |
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| 490 | + fallthrough; |
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408 | 491 | case -ENOKEY: /* negative key */ |
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409 | 492 | ret = key_ref; |
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410 | 493 | break; |
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.. | .. |
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414 | 497 | } |
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415 | 498 | } |
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416 | 499 | /* or search the user-session keyring */ |
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417 | | - else if (ctx->cred->user->session_keyring) { |
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418 | | - key_ref = keyring_search_aux( |
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419 | | - make_key_ref(ctx->cred->user->session_keyring, 1), |
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420 | | - ctx); |
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| 500 | + else if ((user_session = get_user_session_keyring_rcu(cred))) { |
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| 501 | + key_ref = keyring_search_rcu(make_key_ref(user_session, 1), |
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| 502 | + ctx); |
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| 503 | + key_put(user_session); |
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| 504 | + |
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421 | 505 | if (!IS_ERR(key_ref)) |
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422 | 506 | goto found; |
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423 | 507 | |
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.. | .. |
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425 | 509 | case -EAGAIN: /* no key */ |
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426 | 510 | if (ret) |
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427 | 511 | break; |
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| 512 | + fallthrough; |
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428 | 513 | case -ENOKEY: /* negative key */ |
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429 | 514 | ret = key_ref; |
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430 | 515 | break; |
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.. | .. |
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447 | 532 | * the keys attached to the assumed authorisation key using its credentials if |
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448 | 533 | * one is available. |
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449 | 534 | * |
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450 | | - * Return same as search_my_process_keyrings(). |
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| 535 | + * The caller must be holding the RCU read lock. |
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| 536 | + * |
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| 537 | + * Return same as search_cred_keyrings_rcu(). |
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451 | 538 | */ |
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452 | | -key_ref_t search_process_keyrings(struct keyring_search_context *ctx) |
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| 539 | +key_ref_t search_process_keyrings_rcu(struct keyring_search_context *ctx) |
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453 | 540 | { |
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454 | 541 | struct request_key_auth *rka; |
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455 | 542 | key_ref_t key_ref, ret = ERR_PTR(-EACCES), err; |
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456 | 543 | |
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457 | | - might_sleep(); |
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458 | | - |
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459 | | - key_ref = search_my_process_keyrings(ctx); |
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| 544 | + key_ref = search_cred_keyrings_rcu(ctx); |
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460 | 545 | if (!IS_ERR(key_ref)) |
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461 | 546 | goto found; |
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462 | 547 | err = key_ref; |
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.. | .. |
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471 | 556 | ) { |
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472 | 557 | const struct cred *cred = ctx->cred; |
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473 | 558 | |
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474 | | - /* defend against the auth key being revoked */ |
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475 | | - down_read(&cred->request_key_auth->sem); |
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476 | | - |
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477 | | - if (key_validate(ctx->cred->request_key_auth) == 0) { |
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| 559 | + if (key_validate(cred->request_key_auth) == 0) { |
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478 | 560 | rka = ctx->cred->request_key_auth->payload.data[0]; |
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479 | 561 | |
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| 562 | + //// was search_process_keyrings() [ie. recursive] |
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480 | 563 | ctx->cred = rka->cred; |
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481 | | - key_ref = search_process_keyrings(ctx); |
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| 564 | + key_ref = search_cred_keyrings_rcu(ctx); |
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482 | 565 | ctx->cred = cred; |
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483 | | - |
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484 | | - up_read(&cred->request_key_auth->sem); |
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485 | 566 | |
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486 | 567 | if (!IS_ERR(key_ref)) |
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487 | 568 | goto found; |
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488 | | - |
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489 | 569 | ret = key_ref; |
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490 | | - } else { |
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491 | | - up_read(&cred->request_key_auth->sem); |
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492 | 570 | } |
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493 | 571 | } |
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494 | 572 | |
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.. | .. |
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503 | 581 | found: |
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504 | 582 | return key_ref; |
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505 | 583 | } |
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506 | | - |
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507 | 584 | /* |
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508 | 585 | * See if the key we're looking at is the target key. |
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509 | 586 | */ |
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.. | .. |
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532 | 609 | * returned key reference. |
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533 | 610 | */ |
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534 | 611 | key_ref_t lookup_user_key(key_serial_t id, unsigned long lflags, |
---|
535 | | - key_perm_t perm) |
---|
| 612 | + enum key_need_perm need_perm) |
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536 | 613 | { |
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537 | 614 | struct keyring_search_context ctx = { |
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538 | 615 | .match_data.cmp = lookup_user_key_possessed, |
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539 | 616 | .match_data.lookup_type = KEYRING_SEARCH_LOOKUP_DIRECT, |
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540 | | - .flags = KEYRING_SEARCH_NO_STATE_CHECK, |
---|
| 617 | + .flags = (KEYRING_SEARCH_NO_STATE_CHECK | |
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| 618 | + KEYRING_SEARCH_RECURSE), |
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541 | 619 | }; |
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542 | 620 | struct request_key_auth *rka; |
---|
543 | | - struct key *key; |
---|
| 621 | + struct key *key, *user_session; |
---|
544 | 622 | key_ref_t key_ref, skey_ref; |
---|
545 | 623 | int ret; |
---|
546 | 624 | |
---|
.. | .. |
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589 | 667 | if (!ctx.cred->session_keyring) { |
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590 | 668 | /* always install a session keyring upon access if one |
---|
591 | 669 | * doesn't exist yet */ |
---|
592 | | - ret = install_user_keyrings(); |
---|
| 670 | + ret = look_up_user_keyrings(NULL, &user_session); |
---|
593 | 671 | if (ret < 0) |
---|
594 | 672 | goto error; |
---|
595 | 673 | if (lflags & KEY_LOOKUP_CREATE) |
---|
596 | 674 | ret = join_session_keyring(NULL); |
---|
597 | 675 | else |
---|
598 | | - ret = install_session_keyring( |
---|
599 | | - ctx.cred->user->session_keyring); |
---|
| 676 | + ret = install_session_keyring(user_session); |
---|
600 | 677 | |
---|
| 678 | + key_put(user_session); |
---|
601 | 679 | if (ret < 0) |
---|
602 | 680 | goto error; |
---|
603 | 681 | goto reget_creds; |
---|
604 | | - } else if (ctx.cred->session_keyring == |
---|
605 | | - ctx.cred->user->session_keyring && |
---|
| 682 | + } else if (test_bit(KEY_FLAG_UID_KEYRING, |
---|
| 683 | + &ctx.cred->session_keyring->flags) && |
---|
606 | 684 | lflags & KEY_LOOKUP_CREATE) { |
---|
607 | 685 | ret = join_session_keyring(NULL); |
---|
608 | 686 | if (ret < 0) |
---|
.. | .. |
---|
610 | 688 | goto reget_creds; |
---|
611 | 689 | } |
---|
612 | 690 | |
---|
613 | | - rcu_read_lock(); |
---|
614 | | - key = rcu_dereference(ctx.cred->session_keyring); |
---|
| 691 | + key = ctx.cred->session_keyring; |
---|
615 | 692 | __key_get(key); |
---|
616 | | - rcu_read_unlock(); |
---|
617 | 693 | key_ref = make_key_ref(key, 1); |
---|
618 | 694 | break; |
---|
619 | 695 | |
---|
620 | 696 | case KEY_SPEC_USER_KEYRING: |
---|
621 | | - if (!ctx.cred->user->uid_keyring) { |
---|
622 | | - ret = install_user_keyrings(); |
---|
623 | | - if (ret < 0) |
---|
624 | | - goto error; |
---|
625 | | - } |
---|
626 | | - |
---|
627 | | - key = ctx.cred->user->uid_keyring; |
---|
628 | | - __key_get(key); |
---|
| 697 | + ret = look_up_user_keyrings(&key, NULL); |
---|
| 698 | + if (ret < 0) |
---|
| 699 | + goto error; |
---|
629 | 700 | key_ref = make_key_ref(key, 1); |
---|
630 | 701 | break; |
---|
631 | 702 | |
---|
632 | 703 | case KEY_SPEC_USER_SESSION_KEYRING: |
---|
633 | | - if (!ctx.cred->user->session_keyring) { |
---|
634 | | - ret = install_user_keyrings(); |
---|
635 | | - if (ret < 0) |
---|
636 | | - goto error; |
---|
637 | | - } |
---|
638 | | - |
---|
639 | | - key = ctx.cred->user->session_keyring; |
---|
640 | | - __key_get(key); |
---|
| 704 | + ret = look_up_user_keyrings(NULL, &key); |
---|
| 705 | + if (ret < 0) |
---|
| 706 | + goto error; |
---|
641 | 707 | key_ref = make_key_ref(key, 1); |
---|
642 | 708 | break; |
---|
643 | 709 | |
---|
.. | .. |
---|
689 | 755 | key_ref = make_key_ref(key, 0); |
---|
690 | 756 | |
---|
691 | 757 | /* check to see if we possess the key */ |
---|
692 | | - ctx.index_key.type = key->type; |
---|
693 | | - ctx.index_key.description = key->description; |
---|
694 | | - ctx.index_key.desc_len = strlen(key->description); |
---|
| 758 | + ctx.index_key = key->index_key; |
---|
695 | 759 | ctx.match_data.raw_data = key; |
---|
696 | 760 | kdebug("check possessed"); |
---|
697 | | - skey_ref = search_process_keyrings(&ctx); |
---|
| 761 | + rcu_read_lock(); |
---|
| 762 | + skey_ref = search_process_keyrings_rcu(&ctx); |
---|
| 763 | + rcu_read_unlock(); |
---|
698 | 764 | kdebug("possessed=%p", skey_ref); |
---|
699 | 765 | |
---|
700 | 766 | if (!IS_ERR(skey_ref)) { |
---|
.. | .. |
---|
707 | 773 | |
---|
708 | 774 | /* unlink does not use the nominated key in any way, so can skip all |
---|
709 | 775 | * the permission checks as it is only concerned with the keyring */ |
---|
710 | | - if (lflags & KEY_LOOKUP_FOR_UNLINK) { |
---|
711 | | - ret = 0; |
---|
712 | | - goto error; |
---|
713 | | - } |
---|
714 | | - |
---|
715 | | - if (!(lflags & KEY_LOOKUP_PARTIAL)) { |
---|
716 | | - ret = wait_for_key_construction(key, true); |
---|
717 | | - switch (ret) { |
---|
718 | | - case -ERESTARTSYS: |
---|
719 | | - goto invalid_key; |
---|
720 | | - default: |
---|
721 | | - if (perm) |
---|
| 776 | + if (need_perm != KEY_NEED_UNLINK) { |
---|
| 777 | + if (!(lflags & KEY_LOOKUP_PARTIAL)) { |
---|
| 778 | + ret = wait_for_key_construction(key, true); |
---|
| 779 | + switch (ret) { |
---|
| 780 | + case -ERESTARTSYS: |
---|
722 | 781 | goto invalid_key; |
---|
723 | | - case 0: |
---|
724 | | - break; |
---|
| 782 | + default: |
---|
| 783 | + if (need_perm != KEY_AUTHTOKEN_OVERRIDE && |
---|
| 784 | + need_perm != KEY_DEFER_PERM_CHECK) |
---|
| 785 | + goto invalid_key; |
---|
| 786 | + case 0: |
---|
| 787 | + break; |
---|
| 788 | + } |
---|
| 789 | + } else if (need_perm != KEY_DEFER_PERM_CHECK) { |
---|
| 790 | + ret = key_validate(key); |
---|
| 791 | + if (ret < 0) |
---|
| 792 | + goto invalid_key; |
---|
725 | 793 | } |
---|
726 | | - } else if (perm) { |
---|
727 | | - ret = key_validate(key); |
---|
728 | | - if (ret < 0) |
---|
| 794 | + |
---|
| 795 | + ret = -EIO; |
---|
| 796 | + if (!(lflags & KEY_LOOKUP_PARTIAL) && |
---|
| 797 | + key_read_state(key) == KEY_IS_UNINSTANTIATED) |
---|
729 | 798 | goto invalid_key; |
---|
730 | 799 | } |
---|
731 | | - |
---|
732 | | - ret = -EIO; |
---|
733 | | - if (!(lflags & KEY_LOOKUP_PARTIAL) && |
---|
734 | | - key_read_state(key) == KEY_IS_UNINSTANTIATED) |
---|
735 | | - goto invalid_key; |
---|
736 | 800 | |
---|
737 | 801 | /* check the permissions */ |
---|
738 | | - ret = key_task_permission(key_ref, ctx.cred, perm); |
---|
| 802 | + ret = key_task_permission(key_ref, ctx.cred, need_perm); |
---|
739 | 803 | if (ret < 0) |
---|
740 | 804 | goto invalid_key; |
---|
741 | 805 | |
---|
.. | .. |
---|
886 | 950 | */ |
---|
887 | 951 | static int __init init_root_keyring(void) |
---|
888 | 952 | { |
---|
889 | | - return install_user_keyrings(); |
---|
| 953 | + return look_up_user_keyrings(NULL, NULL); |
---|
890 | 954 | } |
---|
891 | 955 | |
---|
892 | 956 | late_initcall(init_root_keyring); |
---|