Thomas Gleixner | b886d83c | 2019-06-01 10:08:55 +0200 | [diff] [blame] | 1 | // SPDX-License-Identifier: GPL-2.0-only |
John Johansen | 898127c | 2010-07-29 14:48:06 -0700 | [diff] [blame] | 2 | /* |
| 3 | * AppArmor security module |
| 4 | * |
| 5 | * This file contains AppArmor policy attachment and domain transitions |
| 6 | * |
| 7 | * Copyright (C) 2002-2008 Novell/SUSE |
| 8 | * Copyright 2009-2010 Canonical Ltd. |
John Johansen | 898127c | 2010-07-29 14:48:06 -0700 | [diff] [blame] | 9 | */ |
| 10 | |
| 11 | #include <linux/errno.h> |
| 12 | #include <linux/fdtable.h> |
Christian Brauner | 3cee607 | 2021-01-21 14:19:44 +0100 | [diff] [blame] | 13 | #include <linux/fs.h> |
John Johansen | 898127c | 2010-07-29 14:48:06 -0700 | [diff] [blame] | 14 | #include <linux/file.h> |
| 15 | #include <linux/mount.h> |
| 16 | #include <linux/syscalls.h> |
John Johansen | 898127c | 2010-07-29 14:48:06 -0700 | [diff] [blame] | 17 | #include <linux/personality.h> |
Matthew Garrett | 8e51f90 | 2018-02-08 12:37:19 -0800 | [diff] [blame] | 18 | #include <linux/xattr.h> |
Christian Brauner | 3cee607 | 2021-01-21 14:19:44 +0100 | [diff] [blame] | 19 | #include <linux/user_namespace.h> |
John Johansen | 898127c | 2010-07-29 14:48:06 -0700 | [diff] [blame] | 20 | |
| 21 | #include "include/audit.h" |
| 22 | #include "include/apparmorfs.h" |
John Johansen | d8889d4 | 2017-10-11 01:04:48 -0700 | [diff] [blame] | 23 | #include "include/cred.h" |
John Johansen | 898127c | 2010-07-29 14:48:06 -0700 | [diff] [blame] | 24 | #include "include/domain.h" |
| 25 | #include "include/file.h" |
| 26 | #include "include/ipc.h" |
| 27 | #include "include/match.h" |
| 28 | #include "include/path.h" |
| 29 | #include "include/policy.h" |
John Johansen | cff281f | 2017-01-16 00:42:15 -0800 | [diff] [blame] | 30 | #include "include/policy_ns.h" |
John Johansen | 898127c | 2010-07-29 14:48:06 -0700 | [diff] [blame] | 31 | |
| 32 | /** |
John Johansen | 898127c | 2010-07-29 14:48:06 -0700 | [diff] [blame] | 33 | * may_change_ptraced_domain - check if can change profile on ptraced task |
Yang Li | cd269ca | 2023-10-23 09:11:23 +0800 | [diff] [blame] | 34 | * @to_cred: cred of task changing domain |
John Johansen | b2d09ae | 2017-06-09 14:22:14 -0700 | [diff] [blame] | 35 | * @to_label: profile to change to (NOT NULL) |
| 36 | * @info: message if there is an error |
John Johansen | 898127c | 2010-07-29 14:48:06 -0700 | [diff] [blame] | 37 | * |
Oleg Nesterov | 51775fe | 2013-10-08 05:46:03 -0700 | [diff] [blame] | 38 | * Check if current is ptraced and if so if the tracing task is allowed |
John Johansen | 898127c | 2010-07-29 14:48:06 -0700 | [diff] [blame] | 39 | * to trace the new domain |
| 40 | * |
| 41 | * Returns: %0 or error if change not allowed |
| 42 | */ |
John Johansen | 90c436a | 2022-09-19 20:48:48 -0700 | [diff] [blame] | 43 | static int may_change_ptraced_domain(const struct cred *to_cred, |
| 44 | struct aa_label *to_label, |
John Johansen | b2d09ae | 2017-06-09 14:22:14 -0700 | [diff] [blame] | 45 | const char **info) |
John Johansen | 898127c | 2010-07-29 14:48:06 -0700 | [diff] [blame] | 46 | { |
| 47 | struct task_struct *tracer; |
John Johansen | 637f688 | 2017-06-09 08:14:28 -0700 | [diff] [blame] | 48 | struct aa_label *tracerl = NULL; |
John Johansen | 90c436a | 2022-09-19 20:48:48 -0700 | [diff] [blame] | 49 | const struct cred *tracer_cred = NULL; |
| 50 | |
John Johansen | 898127c | 2010-07-29 14:48:06 -0700 | [diff] [blame] | 51 | int error = 0; |
| 52 | |
| 53 | rcu_read_lock(); |
Oleg Nesterov | 51775fe | 2013-10-08 05:46:03 -0700 | [diff] [blame] | 54 | tracer = ptrace_parent(current); |
John Johansen | 90c436a | 2022-09-19 20:48:48 -0700 | [diff] [blame] | 55 | if (tracer) { |
John Johansen | 898127c | 2010-07-29 14:48:06 -0700 | [diff] [blame] | 56 | /* released below */ |
John Johansen | 637f688 | 2017-06-09 08:14:28 -0700 | [diff] [blame] | 57 | tracerl = aa_get_task_label(tracer); |
John Johansen | 90c436a | 2022-09-19 20:48:48 -0700 | [diff] [blame] | 58 | tracer_cred = get_task_cred(tracer); |
| 59 | } |
John Johansen | 898127c | 2010-07-29 14:48:06 -0700 | [diff] [blame] | 60 | /* not ptraced */ |
John Johansen | 637f688 | 2017-06-09 08:14:28 -0700 | [diff] [blame] | 61 | if (!tracer || unconfined(tracerl)) |
John Johansen | 898127c | 2010-07-29 14:48:06 -0700 | [diff] [blame] | 62 | goto out; |
| 63 | |
John Johansen | 90c436a | 2022-09-19 20:48:48 -0700 | [diff] [blame] | 64 | error = aa_may_ptrace(tracer_cred, tracerl, to_cred, to_label, |
| 65 | PTRACE_MODE_ATTACH); |
John Johansen | 898127c | 2010-07-29 14:48:06 -0700 | [diff] [blame] | 66 | |
| 67 | out: |
John Johansen | 04fdc09 | 2011-06-28 15:06:38 +0100 | [diff] [blame] | 68 | rcu_read_unlock(); |
John Johansen | 637f688 | 2017-06-09 08:14:28 -0700 | [diff] [blame] | 69 | aa_put_label(tracerl); |
John Johansen | 90c436a | 2022-09-19 20:48:48 -0700 | [diff] [blame] | 70 | put_cred(tracer_cred); |
John Johansen | 898127c | 2010-07-29 14:48:06 -0700 | [diff] [blame] | 71 | |
John Johansen | b2d09ae | 2017-06-09 14:22:14 -0700 | [diff] [blame] | 72 | if (error) |
| 73 | *info = "ptrace prevents transition"; |
John Johansen | 898127c | 2010-07-29 14:48:06 -0700 | [diff] [blame] | 74 | return error; |
| 75 | } |
| 76 | |
John Johansen | 93c98a4 | 2017-06-09 16:55:04 -0700 | [diff] [blame] | 77 | /**** TODO: dedup to aa_label_match - needs perm and dfa, merging |
| 78 | * specifically this is an exact copy of aa_label_match except |
| 79 | * aa_compute_perms is replaced with aa_compute_fperms |
John Johansen | 98b824f | 2023-04-28 05:32:52 -0700 | [diff] [blame] | 80 | * and policy->dfa with file->dfa |
John Johansen | 93c98a4 | 2017-06-09 16:55:04 -0700 | [diff] [blame] | 81 | ****/ |
| 82 | /* match a profile and its associated ns component if needed |
| 83 | * Assumes visibility test has already been done. |
| 84 | * If a subns profile is not to be matched should be prescreened with |
| 85 | * visibility test. |
| 86 | */ |
John Johansen | 33fc95d | 2022-01-17 13:43:49 -0800 | [diff] [blame] | 87 | static inline aa_state_t match_component(struct aa_profile *profile, |
| 88 | struct aa_profile *tp, |
| 89 | bool stack, aa_state_t state) |
John Johansen | 93c98a4 | 2017-06-09 16:55:04 -0700 | [diff] [blame] | 90 | { |
John Johansen | 1ad22fc | 2022-09-05 20:47:36 -0700 | [diff] [blame] | 91 | struct aa_ruleset *rules = list_first_entry(&profile->rules, |
| 92 | typeof(*rules), list); |
John Johansen | 93c98a4 | 2017-06-09 16:55:04 -0700 | [diff] [blame] | 93 | const char *ns_name; |
| 94 | |
| 95 | if (stack) |
John Johansen | 98b824f | 2023-04-28 05:32:52 -0700 | [diff] [blame] | 96 | state = aa_dfa_match(rules->file->dfa, state, "&"); |
John Johansen | 93c98a4 | 2017-06-09 16:55:04 -0700 | [diff] [blame] | 97 | if (profile->ns == tp->ns) |
John Johansen | 98b824f | 2023-04-28 05:32:52 -0700 | [diff] [blame] | 98 | return aa_dfa_match(rules->file->dfa, state, tp->base.hname); |
John Johansen | 93c98a4 | 2017-06-09 16:55:04 -0700 | [diff] [blame] | 99 | |
| 100 | /* try matching with namespace name and then profile */ |
| 101 | ns_name = aa_ns_name(profile->ns, tp->ns, true); |
John Johansen | 98b824f | 2023-04-28 05:32:52 -0700 | [diff] [blame] | 102 | state = aa_dfa_match_len(rules->file->dfa, state, ":", 1); |
| 103 | state = aa_dfa_match(rules->file->dfa, state, ns_name); |
| 104 | state = aa_dfa_match_len(rules->file->dfa, state, ":", 1); |
| 105 | return aa_dfa_match(rules->file->dfa, state, tp->base.hname); |
John Johansen | 93c98a4 | 2017-06-09 16:55:04 -0700 | [diff] [blame] | 106 | } |
| 107 | |
| 108 | /** |
| 109 | * label_compound_match - find perms for full compound label |
| 110 | * @profile: profile to find perms for |
| 111 | * @label: label to check access permissions for |
| 112 | * @stack: whether this is a stacking request |
Yang Li | bab1f77 | 2022-03-17 09:03:30 +0800 | [diff] [blame] | 113 | * @state: state to start match in |
John Johansen | 93c98a4 | 2017-06-09 16:55:04 -0700 | [diff] [blame] | 114 | * @subns: whether to do permission checks on components in a subns |
| 115 | * @request: permissions to request |
| 116 | * @perms: perms struct to set |
| 117 | * |
| 118 | * Returns: 0 on success else ERROR |
| 119 | * |
| 120 | * For the label A//&B//&C this does the perm match for A//&B//&C |
| 121 | * @perms should be preinitialized with allperms OR a previous permission |
| 122 | * check to be stacked. |
| 123 | */ |
| 124 | static int label_compound_match(struct aa_profile *profile, |
| 125 | struct aa_label *label, bool stack, |
John Johansen | 33fc95d | 2022-01-17 13:43:49 -0800 | [diff] [blame] | 126 | aa_state_t state, bool subns, u32 request, |
John Johansen | 93c98a4 | 2017-06-09 16:55:04 -0700 | [diff] [blame] | 127 | struct aa_perms *perms) |
| 128 | { |
John Johansen | 1ad22fc | 2022-09-05 20:47:36 -0700 | [diff] [blame] | 129 | struct aa_ruleset *rules = list_first_entry(&profile->rules, |
| 130 | typeof(*rules), list); |
John Johansen | 93c98a4 | 2017-06-09 16:55:04 -0700 | [diff] [blame] | 131 | struct aa_profile *tp; |
| 132 | struct label_it i; |
| 133 | struct path_cond cond = { }; |
| 134 | |
| 135 | /* find first subcomponent that is visible */ |
| 136 | label_for_each(i, label, tp) { |
| 137 | if (!aa_ns_visible(profile->ns, tp->ns, subns)) |
| 138 | continue; |
| 139 | state = match_component(profile, tp, stack, state); |
| 140 | if (!state) |
| 141 | goto fail; |
| 142 | goto next; |
| 143 | } |
| 144 | |
| 145 | /* no component visible */ |
| 146 | *perms = allperms; |
| 147 | return 0; |
| 148 | |
| 149 | next: |
| 150 | label_for_each_cont(i, label, tp) { |
| 151 | if (!aa_ns_visible(profile->ns, tp->ns, subns)) |
| 152 | continue; |
John Johansen | 98b824f | 2023-04-28 05:32:52 -0700 | [diff] [blame] | 153 | state = aa_dfa_match(rules->file->dfa, state, "//&"); |
John Johansen | 93c98a4 | 2017-06-09 16:55:04 -0700 | [diff] [blame] | 154 | state = match_component(profile, tp, false, state); |
| 155 | if (!state) |
| 156 | goto fail; |
| 157 | } |
John Johansen | 98b824f | 2023-04-28 05:32:52 -0700 | [diff] [blame] | 158 | *perms = *(aa_lookup_fperms(rules->file, state, &cond)); |
John Johansen | 93c98a4 | 2017-06-09 16:55:04 -0700 | [diff] [blame] | 159 | aa_apply_modes_to_perms(profile, perms); |
| 160 | if ((perms->allow & request) != request) |
| 161 | return -EACCES; |
| 162 | |
| 163 | return 0; |
| 164 | |
| 165 | fail: |
| 166 | *perms = nullperms; |
| 167 | return -EACCES; |
| 168 | } |
| 169 | |
| 170 | /** |
| 171 | * label_components_match - find perms for all subcomponents of a label |
| 172 | * @profile: profile to find perms for |
| 173 | * @label: label to check access permissions for |
| 174 | * @stack: whether this is a stacking request |
| 175 | * @start: state to start match in |
| 176 | * @subns: whether to do permission checks on components in a subns |
| 177 | * @request: permissions to request |
| 178 | * @perms: an initialized perms struct to add accumulation to |
| 179 | * |
| 180 | * Returns: 0 on success else ERROR |
| 181 | * |
| 182 | * For the label A//&B//&C this does the perm match for each of A and B and C |
| 183 | * @perms should be preinitialized with allperms OR a previous permission |
| 184 | * check to be stacked. |
| 185 | */ |
| 186 | static int label_components_match(struct aa_profile *profile, |
| 187 | struct aa_label *label, bool stack, |
John Johansen | 33fc95d | 2022-01-17 13:43:49 -0800 | [diff] [blame] | 188 | aa_state_t start, bool subns, u32 request, |
John Johansen | 93c98a4 | 2017-06-09 16:55:04 -0700 | [diff] [blame] | 189 | struct aa_perms *perms) |
| 190 | { |
John Johansen | 1ad22fc | 2022-09-05 20:47:36 -0700 | [diff] [blame] | 191 | struct aa_ruleset *rules = list_first_entry(&profile->rules, |
| 192 | typeof(*rules), list); |
John Johansen | 93c98a4 | 2017-06-09 16:55:04 -0700 | [diff] [blame] | 193 | struct aa_profile *tp; |
| 194 | struct label_it i; |
| 195 | struct aa_perms tmp; |
| 196 | struct path_cond cond = { }; |
John Johansen | 33fc95d | 2022-01-17 13:43:49 -0800 | [diff] [blame] | 197 | aa_state_t state = 0; |
John Johansen | 93c98a4 | 2017-06-09 16:55:04 -0700 | [diff] [blame] | 198 | |
| 199 | /* find first subcomponent to test */ |
| 200 | label_for_each(i, label, tp) { |
| 201 | if (!aa_ns_visible(profile->ns, tp->ns, subns)) |
| 202 | continue; |
| 203 | state = match_component(profile, tp, stack, start); |
| 204 | if (!state) |
| 205 | goto fail; |
| 206 | goto next; |
| 207 | } |
| 208 | |
| 209 | /* no subcomponents visible - no change in perms */ |
| 210 | return 0; |
| 211 | |
| 212 | next: |
John Johansen | 98b824f | 2023-04-28 05:32:52 -0700 | [diff] [blame] | 213 | tmp = *(aa_lookup_fperms(rules->file, state, &cond)); |
John Johansen | 93c98a4 | 2017-06-09 16:55:04 -0700 | [diff] [blame] | 214 | aa_apply_modes_to_perms(profile, &tmp); |
| 215 | aa_perms_accum(perms, &tmp); |
| 216 | label_for_each_cont(i, label, tp) { |
| 217 | if (!aa_ns_visible(profile->ns, tp->ns, subns)) |
| 218 | continue; |
| 219 | state = match_component(profile, tp, stack, start); |
| 220 | if (!state) |
| 221 | goto fail; |
John Johansen | 98b824f | 2023-04-28 05:32:52 -0700 | [diff] [blame] | 222 | tmp = *(aa_lookup_fperms(rules->file, state, &cond)); |
John Johansen | 93c98a4 | 2017-06-09 16:55:04 -0700 | [diff] [blame] | 223 | aa_apply_modes_to_perms(profile, &tmp); |
| 224 | aa_perms_accum(perms, &tmp); |
| 225 | } |
| 226 | |
| 227 | if ((perms->allow & request) != request) |
| 228 | return -EACCES; |
| 229 | |
| 230 | return 0; |
| 231 | |
| 232 | fail: |
| 233 | *perms = nullperms; |
| 234 | return -EACCES; |
| 235 | } |
| 236 | |
| 237 | /** |
| 238 | * label_match - do a multi-component label match |
| 239 | * @profile: profile to match against (NOT NULL) |
| 240 | * @label: label to match (NOT NULL) |
| 241 | * @stack: whether this is a stacking request |
| 242 | * @state: state to start in |
| 243 | * @subns: whether to match subns components |
| 244 | * @request: permission request |
| 245 | * @perms: Returns computed perms (NOT NULL) |
| 246 | * |
| 247 | * Returns: the state the match finished in, may be the none matching state |
| 248 | */ |
| 249 | static int label_match(struct aa_profile *profile, struct aa_label *label, |
John Johansen | 33fc95d | 2022-01-17 13:43:49 -0800 | [diff] [blame] | 250 | bool stack, aa_state_t state, bool subns, u32 request, |
John Johansen | 93c98a4 | 2017-06-09 16:55:04 -0700 | [diff] [blame] | 251 | struct aa_perms *perms) |
| 252 | { |
| 253 | int error; |
| 254 | |
| 255 | *perms = nullperms; |
| 256 | error = label_compound_match(profile, label, stack, state, subns, |
| 257 | request, perms); |
| 258 | if (!error) |
| 259 | return error; |
| 260 | |
| 261 | *perms = allperms; |
| 262 | return label_components_match(profile, label, stack, state, subns, |
| 263 | request, perms); |
| 264 | } |
| 265 | |
| 266 | /******* end TODO: dedup *****/ |
| 267 | |
John Johansen | 898127c | 2010-07-29 14:48:06 -0700 | [diff] [blame] | 268 | /** |
| 269 | * change_profile_perms - find permissions for change_profile |
| 270 | * @profile: the current profile (NOT NULL) |
John Johansen | 93c98a4 | 2017-06-09 16:55:04 -0700 | [diff] [blame] | 271 | * @target: label to transition to (NOT NULL) |
| 272 | * @stack: whether this is a stacking request |
John Johansen | 898127c | 2010-07-29 14:48:06 -0700 | [diff] [blame] | 273 | * @request: requested perms |
| 274 | * @start: state to start matching in |
Gaosheng Cui | 76426c9d | 2023-06-25 09:13:41 +0800 | [diff] [blame] | 275 | * @perms: Returns computed perms (NOT NULL) |
John Johansen | 898127c | 2010-07-29 14:48:06 -0700 | [diff] [blame] | 276 | * |
John Johansen | 93c98a4 | 2017-06-09 16:55:04 -0700 | [diff] [blame] | 277 | * |
John Johansen | 898127c | 2010-07-29 14:48:06 -0700 | [diff] [blame] | 278 | * Returns: permission set |
John Johansen | 93c98a4 | 2017-06-09 16:55:04 -0700 | [diff] [blame] | 279 | * |
| 280 | * currently only matches full label A//&B//&C or individual components A, B, C |
| 281 | * not arbitrary combinations. Eg. A//&B, C |
John Johansen | 898127c | 2010-07-29 14:48:06 -0700 | [diff] [blame] | 282 | */ |
John Johansen | 93c98a4 | 2017-06-09 16:55:04 -0700 | [diff] [blame] | 283 | static int change_profile_perms(struct aa_profile *profile, |
| 284 | struct aa_label *target, bool stack, |
John Johansen | 33fc95d | 2022-01-17 13:43:49 -0800 | [diff] [blame] | 285 | u32 request, aa_state_t start, |
John Johansen | 93c98a4 | 2017-06-09 16:55:04 -0700 | [diff] [blame] | 286 | struct aa_perms *perms) |
| 287 | { |
| 288 | if (profile_unconfined(profile)) { |
| 289 | perms->allow = AA_MAY_CHANGE_PROFILE | AA_MAY_ONEXEC; |
| 290 | perms->audit = perms->quiet = perms->kill = 0; |
| 291 | return 0; |
| 292 | } |
| 293 | |
| 294 | /* TODO: add profile in ns screening */ |
| 295 | return label_match(profile, target, stack, start, true, request, perms); |
| 296 | } |
| 297 | |
John Johansen | 898127c | 2010-07-29 14:48:06 -0700 | [diff] [blame] | 298 | /** |
Matthew Garrett | 8e51f90 | 2018-02-08 12:37:19 -0800 | [diff] [blame] | 299 | * aa_xattrs_match - check whether a file matches the xattrs defined in profile |
| 300 | * @bprm: binprm struct for the process to validate |
| 301 | * @profile: profile to match against (NOT NULL) |
John Johansen | 73f488c | 2017-12-12 15:28:05 -0800 | [diff] [blame] | 302 | * @state: state to start match in |
Matthew Garrett | 8e51f90 | 2018-02-08 12:37:19 -0800 | [diff] [blame] | 303 | * |
| 304 | * Returns: number of extended attributes that matched, or < 0 on error |
| 305 | */ |
| 306 | static int aa_xattrs_match(const struct linux_binprm *bprm, |
John Johansen | 33fc95d | 2022-01-17 13:43:49 -0800 | [diff] [blame] | 307 | struct aa_profile *profile, aa_state_t state) |
Matthew Garrett | 8e51f90 | 2018-02-08 12:37:19 -0800 | [diff] [blame] | 308 | { |
| 309 | int i; |
Matthew Garrett | 8e51f90 | 2018-02-08 12:37:19 -0800 | [diff] [blame] | 310 | struct dentry *d; |
| 311 | char *value = NULL; |
John Johansen | 217af7e | 2022-07-29 17:17:31 -0700 | [diff] [blame] | 312 | struct aa_attachment *attach = &profile->attach; |
Linus Torvalds | 93761c9 | 2022-12-14 13:42:09 -0800 | [diff] [blame] | 313 | int size, value_size = 0, ret = attach->xattr_count; |
Matthew Garrett | 8e51f90 | 2018-02-08 12:37:19 -0800 | [diff] [blame] | 314 | |
John Johansen | 217af7e | 2022-07-29 17:17:31 -0700 | [diff] [blame] | 315 | if (!bprm || !attach->xattr_count) |
Matthew Garrett | 8e51f90 | 2018-02-08 12:37:19 -0800 | [diff] [blame] | 316 | return 0; |
John Johansen | 8c62ed2 | 2020-01-02 05:31:22 -0800 | [diff] [blame] | 317 | might_sleep(); |
Matthew Garrett | 8e51f90 | 2018-02-08 12:37:19 -0800 | [diff] [blame] | 318 | |
John Johansen | 73f488c | 2017-12-12 15:28:05 -0800 | [diff] [blame] | 319 | /* transition from exec match to xattr set */ |
John Johansen | 98b824f | 2023-04-28 05:32:52 -0700 | [diff] [blame] | 320 | state = aa_dfa_outofband_transition(attach->xmatch->dfa, state); |
Matthew Garrett | 8e51f90 | 2018-02-08 12:37:19 -0800 | [diff] [blame] | 321 | d = bprm->file->f_path.dentry; |
| 322 | |
John Johansen | 217af7e | 2022-07-29 17:17:31 -0700 | [diff] [blame] | 323 | for (i = 0; i < attach->xattr_count; i++) { |
Christian Brauner | 4609e1f | 2023-01-13 12:49:22 +0100 | [diff] [blame] | 324 | size = vfs_getxattr_alloc(&nop_mnt_idmap, d, attach->xattrs[i], |
Tycho Andersen | c7c7a1a1 | 2021-01-21 14:19:28 +0100 | [diff] [blame] | 325 | &value, value_size, GFP_KERNEL); |
John Johansen | 73f488c | 2017-12-12 15:28:05 -0800 | [diff] [blame] | 326 | if (size >= 0) { |
John Johansen | 2d63dd4 | 2020-11-13 23:36:09 -0800 | [diff] [blame] | 327 | u32 index, perm; |
John Johansen | 73f488c | 2017-12-12 15:28:05 -0800 | [diff] [blame] | 328 | |
John Johansen | 0df34a6 | 2019-07-30 02:42:13 -0700 | [diff] [blame] | 329 | /* |
| 330 | * Check the xattr presence before value. This ensure |
| 331 | * that not present xattr can be distinguished from a 0 |
| 332 | * length value or rule that matches any value |
| 333 | */ |
John Johansen | 98b824f | 2023-04-28 05:32:52 -0700 | [diff] [blame] | 334 | state = aa_dfa_null_transition(attach->xmatch->dfa, |
John Johansen | 048d495 | 2020-11-21 01:42:40 -0800 | [diff] [blame] | 335 | state); |
John Johansen | 0df34a6 | 2019-07-30 02:42:13 -0700 | [diff] [blame] | 336 | /* Check xattr value */ |
John Johansen | 98b824f | 2023-04-28 05:32:52 -0700 | [diff] [blame] | 337 | state = aa_dfa_match_len(attach->xmatch->dfa, state, |
John Johansen | 048d495 | 2020-11-21 01:42:40 -0800 | [diff] [blame] | 338 | value, size); |
John Johansen | 98b824f | 2023-04-28 05:32:52 -0700 | [diff] [blame] | 339 | index = ACCEPT_TABLE(attach->xmatch->dfa)[state]; |
| 340 | perm = attach->xmatch->perms[index].allow; |
John Johansen | 73f488c | 2017-12-12 15:28:05 -0800 | [diff] [blame] | 341 | if (!(perm & MAY_EXEC)) { |
| 342 | ret = -EINVAL; |
| 343 | goto out; |
| 344 | } |
Matthew Garrett | 8e51f90 | 2018-02-08 12:37:19 -0800 | [diff] [blame] | 345 | } |
John Johansen | 73f488c | 2017-12-12 15:28:05 -0800 | [diff] [blame] | 346 | /* transition to next element */ |
John Johansen | 98b824f | 2023-04-28 05:32:52 -0700 | [diff] [blame] | 347 | state = aa_dfa_outofband_transition(attach->xmatch->dfa, state); |
John Johansen | 73f488c | 2017-12-12 15:28:05 -0800 | [diff] [blame] | 348 | if (size < 0) { |
| 349 | /* |
| 350 | * No xattr match, so verify if transition to |
| 351 | * next element was valid. IFF so the xattr |
| 352 | * was optional. |
| 353 | */ |
| 354 | if (!state) { |
Matthew Garrett | 8e51f90 | 2018-02-08 12:37:19 -0800 | [diff] [blame] | 355 | ret = -EINVAL; |
| 356 | goto out; |
| 357 | } |
John Johansen | 73f488c | 2017-12-12 15:28:05 -0800 | [diff] [blame] | 358 | /* don't count missing optional xattr as matched */ |
| 359 | ret--; |
Matthew Garrett | 8e51f90 | 2018-02-08 12:37:19 -0800 | [diff] [blame] | 360 | } |
| 361 | } |
| 362 | |
| 363 | out: |
| 364 | kfree(value); |
| 365 | return ret; |
| 366 | } |
| 367 | |
| 368 | /** |
John Johansen | 8c62ed2 | 2020-01-02 05:31:22 -0800 | [diff] [blame] | 369 | * find_attach - do attachment search for unconfined processes |
Gaosheng Cui | 76426c9d | 2023-06-25 09:13:41 +0800 | [diff] [blame] | 370 | * @bprm: binprm structure of transitioning task |
John Johansen | 8c62ed2 | 2020-01-02 05:31:22 -0800 | [diff] [blame] | 371 | * @ns: the current namespace (NOT NULL) |
Gaosheng Cui | 76426c9d | 2023-06-25 09:13:41 +0800 | [diff] [blame] | 372 | * @head: profile list to walk (NOT NULL) |
| 373 | * @name: to match against (NOT NULL) |
| 374 | * @info: info message if there was an error (NOT NULL) |
John Johansen | 898127c | 2010-07-29 14:48:06 -0700 | [diff] [blame] | 375 | * |
| 376 | * Do a linear search on the profiles in the list. There is a matching |
| 377 | * preference where an exact match is preferred over a name which uses |
| 378 | * expressions to match, and matching expressions with the greatest |
| 379 | * xmatch_len are preferred. |
| 380 | * |
| 381 | * Requires: @head not be shared or have appropriate locks held |
| 382 | * |
John Johansen | 8c62ed2 | 2020-01-02 05:31:22 -0800 | [diff] [blame] | 383 | * Returns: label or NULL if no match found |
John Johansen | 898127c | 2010-07-29 14:48:06 -0700 | [diff] [blame] | 384 | */ |
John Johansen | 8c62ed2 | 2020-01-02 05:31:22 -0800 | [diff] [blame] | 385 | static struct aa_label *find_attach(const struct linux_binprm *bprm, |
| 386 | struct aa_ns *ns, struct list_head *head, |
| 387 | const char *name, const char **info) |
John Johansen | 898127c | 2010-07-29 14:48:06 -0700 | [diff] [blame] | 388 | { |
John Johansen | 21f6066 | 2017-11-18 19:43:13 -0800 | [diff] [blame] | 389 | int candidate_len = 0, candidate_xattrs = 0; |
John Johansen | 844b829 | 2017-11-17 17:42:42 -0800 | [diff] [blame] | 390 | bool conflict = false; |
John Johansen | 898127c | 2010-07-29 14:48:06 -0700 | [diff] [blame] | 391 | struct aa_profile *profile, *candidate = NULL; |
| 392 | |
John Johansen | 21f6066 | 2017-11-18 19:43:13 -0800 | [diff] [blame] | 393 | AA_BUG(!name); |
| 394 | AA_BUG(!head); |
| 395 | |
John Johansen | 8c62ed2 | 2020-01-02 05:31:22 -0800 | [diff] [blame] | 396 | rcu_read_lock(); |
| 397 | restart: |
John Johansen | 01e2b67 | 2013-07-10 21:06:43 -0700 | [diff] [blame] | 398 | list_for_each_entry_rcu(profile, head, base.list) { |
John Johansen | 217af7e | 2022-07-29 17:17:31 -0700 | [diff] [blame] | 399 | struct aa_attachment *attach = &profile->attach; |
| 400 | |
John Johansen | 06d426d | 2017-11-17 18:04:37 -0800 | [diff] [blame] | 401 | if (profile->label.flags & FLAG_NULL && |
| 402 | &profile->label == ns_unconfined(profile->ns)) |
John Johansen | 898127c | 2010-07-29 14:48:06 -0700 | [diff] [blame] | 403 | continue; |
John Johansen | 06d426d | 2017-11-17 18:04:37 -0800 | [diff] [blame] | 404 | |
Matthew Garrett | 8e51f90 | 2018-02-08 12:37:19 -0800 | [diff] [blame] | 405 | /* Find the "best" matching profile. Profiles must |
| 406 | * match the path and extended attributes (if any) |
| 407 | * associated with the file. A more specific path |
| 408 | * match will be preferred over a less specific one, |
| 409 | * and a match with more matching extended attributes |
| 410 | * will be preferred over one with fewer. If the best |
| 411 | * match has both the same level of path specificity |
| 412 | * and the same number of matching extended attributes |
| 413 | * as another profile, signal a conflict and refuse to |
| 414 | * match. |
| 415 | */ |
John Johansen | 98b824f | 2023-04-28 05:32:52 -0700 | [diff] [blame] | 416 | if (attach->xmatch->dfa) { |
John Johansen | 33fc95d | 2022-01-17 13:43:49 -0800 | [diff] [blame] | 417 | unsigned int count; |
| 418 | aa_state_t state; |
John Johansen | 2d63dd4 | 2020-11-13 23:36:09 -0800 | [diff] [blame] | 419 | u32 index, perm; |
John Johansen | 844b829 | 2017-11-17 17:42:42 -0800 | [diff] [blame] | 420 | |
John Johansen | 98b824f | 2023-04-28 05:32:52 -0700 | [diff] [blame] | 421 | state = aa_dfa_leftmatch(attach->xmatch->dfa, |
| 422 | attach->xmatch->start[AA_CLASS_XMATCH], |
John Johansen | 048d495 | 2020-11-21 01:42:40 -0800 | [diff] [blame] | 423 | name, &count); |
John Johansen | 98b824f | 2023-04-28 05:32:52 -0700 | [diff] [blame] | 424 | index = ACCEPT_TABLE(attach->xmatch->dfa)[state]; |
| 425 | perm = attach->xmatch->perms[index].allow; |
Matthew Garrett | 8e51f90 | 2018-02-08 12:37:19 -0800 | [diff] [blame] | 426 | /* any accepting state means a valid match. */ |
| 427 | if (perm & MAY_EXEC) { |
John Johansen | 8c62ed2 | 2020-01-02 05:31:22 -0800 | [diff] [blame] | 428 | int ret = 0; |
Matthew Garrett | 8e51f90 | 2018-02-08 12:37:19 -0800 | [diff] [blame] | 429 | |
John Johansen | 21f6066 | 2017-11-18 19:43:13 -0800 | [diff] [blame] | 430 | if (count < candidate_len) |
| 431 | continue; |
| 432 | |
John Johansen | 217af7e | 2022-07-29 17:17:31 -0700 | [diff] [blame] | 433 | if (bprm && attach->xattr_count) { |
John Johansen | 8c62ed2 | 2020-01-02 05:31:22 -0800 | [diff] [blame] | 434 | long rev = READ_ONCE(ns->revision); |
Matthew Garrett | 8e51f90 | 2018-02-08 12:37:19 -0800 | [diff] [blame] | 435 | |
John Johansen | 8c62ed2 | 2020-01-02 05:31:22 -0800 | [diff] [blame] | 436 | if (!aa_get_profile_not0(profile)) |
| 437 | goto restart; |
| 438 | rcu_read_unlock(); |
| 439 | ret = aa_xattrs_match(bprm, profile, |
| 440 | state); |
| 441 | rcu_read_lock(); |
| 442 | aa_put_profile(profile); |
| 443 | if (rev != |
| 444 | READ_ONCE(ns->revision)) |
| 445 | /* policy changed */ |
| 446 | goto restart; |
| 447 | /* |
| 448 | * Fail matching if the xattrs don't |
| 449 | * match |
| 450 | */ |
| 451 | if (ret < 0) |
| 452 | continue; |
| 453 | } |
John Johansen | 73f488c | 2017-12-12 15:28:05 -0800 | [diff] [blame] | 454 | /* |
| 455 | * TODO: allow for more flexible best match |
| 456 | * |
| 457 | * The new match isn't more specific |
Matthew Garrett | 8e51f90 | 2018-02-08 12:37:19 -0800 | [diff] [blame] | 458 | * than the current best match |
| 459 | */ |
John Johansen | 21f6066 | 2017-11-18 19:43:13 -0800 | [diff] [blame] | 460 | if (count == candidate_len && |
| 461 | ret <= candidate_xattrs) { |
Matthew Garrett | 8e51f90 | 2018-02-08 12:37:19 -0800 | [diff] [blame] | 462 | /* Match is equivalent, so conflict */ |
John Johansen | 21f6066 | 2017-11-18 19:43:13 -0800 | [diff] [blame] | 463 | if (ret == candidate_xattrs) |
Matthew Garrett | 1a3881d | 2018-01-11 13:07:54 -0800 | [diff] [blame] | 464 | conflict = true; |
Matthew Garrett | 8e51f90 | 2018-02-08 12:37:19 -0800 | [diff] [blame] | 465 | continue; |
John Johansen | 844b829 | 2017-11-17 17:42:42 -0800 | [diff] [blame] | 466 | } |
Matthew Garrett | 8e51f90 | 2018-02-08 12:37:19 -0800 | [diff] [blame] | 467 | |
| 468 | /* Either the same length with more matching |
| 469 | * xattrs, or a longer match |
| 470 | */ |
| 471 | candidate = profile; |
John Johansen | 217af7e | 2022-07-29 17:17:31 -0700 | [diff] [blame] | 472 | candidate_len = max(count, attach->xmatch_len); |
John Johansen | 21f6066 | 2017-11-18 19:43:13 -0800 | [diff] [blame] | 473 | candidate_xattrs = ret; |
Matthew Garrett | 8e51f90 | 2018-02-08 12:37:19 -0800 | [diff] [blame] | 474 | conflict = false; |
John Johansen | 898127c | 2010-07-29 14:48:06 -0700 | [diff] [blame] | 475 | } |
John Johansen | 8c62ed2 | 2020-01-02 05:31:22 -0800 | [diff] [blame] | 476 | } else if (!strcmp(profile->base.name, name)) { |
John Johansen | 73f488c | 2017-12-12 15:28:05 -0800 | [diff] [blame] | 477 | /* |
| 478 | * old exact non-re match, without conditionals such |
| 479 | * as xattrs. no more searching required |
| 480 | */ |
John Johansen | 8c62ed2 | 2020-01-02 05:31:22 -0800 | [diff] [blame] | 481 | candidate = profile; |
| 482 | goto out; |
| 483 | } |
John Johansen | 898127c | 2010-07-29 14:48:06 -0700 | [diff] [blame] | 484 | } |
| 485 | |
John Johansen | 8c62ed2 | 2020-01-02 05:31:22 -0800 | [diff] [blame] | 486 | if (!candidate || conflict) { |
| 487 | if (conflict) |
| 488 | *info = "conflicting profile attachments"; |
| 489 | rcu_read_unlock(); |
John Johansen | 844b829 | 2017-11-17 17:42:42 -0800 | [diff] [blame] | 490 | return NULL; |
| 491 | } |
| 492 | |
John Johansen | 8c62ed2 | 2020-01-02 05:31:22 -0800 | [diff] [blame] | 493 | out: |
| 494 | candidate = aa_get_newest_profile(candidate); |
John Johansen | 01e2b67 | 2013-07-10 21:06:43 -0700 | [diff] [blame] | 495 | rcu_read_unlock(); |
John Johansen | 898127c | 2010-07-29 14:48:06 -0700 | [diff] [blame] | 496 | |
John Johansen | 8c62ed2 | 2020-01-02 05:31:22 -0800 | [diff] [blame] | 497 | return &candidate->label; |
John Johansen | 898127c | 2010-07-29 14:48:06 -0700 | [diff] [blame] | 498 | } |
| 499 | |
| 500 | static const char *next_name(int xtype, const char *name) |
| 501 | { |
| 502 | return NULL; |
| 503 | } |
| 504 | |
| 505 | /** |
| 506 | * x_table_lookup - lookup an x transition name via transition table |
| 507 | * @profile: current profile (NOT NULL) |
| 508 | * @xindex: index into x transition table |
John Johansen | 93c98a4 | 2017-06-09 16:55:04 -0700 | [diff] [blame] | 509 | * @name: returns: name tested to find label (NOT NULL) |
John Johansen | 898127c | 2010-07-29 14:48:06 -0700 | [diff] [blame] | 510 | * |
John Johansen | 93c98a4 | 2017-06-09 16:55:04 -0700 | [diff] [blame] | 511 | * Returns: refcounted label, or NULL on failure (MAYBE NULL) |
John Johansen | 898127c | 2010-07-29 14:48:06 -0700 | [diff] [blame] | 512 | */ |
John Johansen | 2ea3ffb | 2017-07-18 23:04:47 -0700 | [diff] [blame] | 513 | struct aa_label *x_table_lookup(struct aa_profile *profile, u32 xindex, |
| 514 | const char **name) |
John Johansen | 898127c | 2010-07-29 14:48:06 -0700 | [diff] [blame] | 515 | { |
John Johansen | 1ad22fc | 2022-09-05 20:47:36 -0700 | [diff] [blame] | 516 | struct aa_ruleset *rules = list_first_entry(&profile->rules, |
| 517 | typeof(*rules), list); |
John Johansen | 93c98a4 | 2017-06-09 16:55:04 -0700 | [diff] [blame] | 518 | struct aa_label *label = NULL; |
John Johansen | 898127c | 2010-07-29 14:48:06 -0700 | [diff] [blame] | 519 | u32 xtype = xindex & AA_X_TYPE_MASK; |
| 520 | int index = xindex & AA_X_INDEX_MASK; |
John Johansen | 93c98a4 | 2017-06-09 16:55:04 -0700 | [diff] [blame] | 521 | |
| 522 | AA_BUG(!name); |
John Johansen | 898127c | 2010-07-29 14:48:06 -0700 | [diff] [blame] | 523 | |
| 524 | /* index is guaranteed to be in range, validated at load time */ |
John Johansen | 93c98a4 | 2017-06-09 16:55:04 -0700 | [diff] [blame] | 525 | /* TODO: move lookup parsing to unpack time so this is a straight |
| 526 | * index into the resultant label |
| 527 | */ |
John Johansen | 98b824f | 2023-04-28 05:32:52 -0700 | [diff] [blame] | 528 | for (*name = rules->file->trans.table[index]; !label && *name; |
John Johansen | 93c98a4 | 2017-06-09 16:55:04 -0700 | [diff] [blame] | 529 | *name = next_name(xtype, *name)) { |
John Johansen | 898127c | 2010-07-29 14:48:06 -0700 | [diff] [blame] | 530 | if (xindex & AA_X_CHILD) { |
John Johansen | 93c98a4 | 2017-06-09 16:55:04 -0700 | [diff] [blame] | 531 | struct aa_profile *new_profile; |
John Johansen | 898127c | 2010-07-29 14:48:06 -0700 | [diff] [blame] | 532 | /* release by caller */ |
John Johansen | 93c98a4 | 2017-06-09 16:55:04 -0700 | [diff] [blame] | 533 | new_profile = aa_find_child(profile, *name); |
| 534 | if (new_profile) |
| 535 | label = &new_profile->label; |
John Johansen | 898127c | 2010-07-29 14:48:06 -0700 | [diff] [blame] | 536 | continue; |
John Johansen | 898127c | 2010-07-29 14:48:06 -0700 | [diff] [blame] | 537 | } |
Sebastian Andrzej Siewior | 8ac2ca3 | 2019-04-05 15:34:58 +0200 | [diff] [blame] | 538 | label = aa_label_parse(&profile->label, *name, GFP_KERNEL, |
John Johansen | 93c98a4 | 2017-06-09 16:55:04 -0700 | [diff] [blame] | 539 | true, false); |
| 540 | if (IS_ERR(label)) |
| 541 | label = NULL; |
John Johansen | 898127c | 2010-07-29 14:48:06 -0700 | [diff] [blame] | 542 | } |
| 543 | |
| 544 | /* released by caller */ |
John Johansen | 93c98a4 | 2017-06-09 16:55:04 -0700 | [diff] [blame] | 545 | |
| 546 | return label; |
John Johansen | 898127c | 2010-07-29 14:48:06 -0700 | [diff] [blame] | 547 | } |
| 548 | |
| 549 | /** |
John Johansen | 93c98a4 | 2017-06-09 16:55:04 -0700 | [diff] [blame] | 550 | * x_to_label - get target label for a given xindex |
John Johansen | 898127c | 2010-07-29 14:48:06 -0700 | [diff] [blame] | 551 | * @profile: current profile (NOT NULL) |
Matthew Garrett | 8e51f90 | 2018-02-08 12:37:19 -0800 | [diff] [blame] | 552 | * @bprm: binprm structure of transitioning task |
John Johansen | 898127c | 2010-07-29 14:48:06 -0700 | [diff] [blame] | 553 | * @name: name to lookup (NOT NULL) |
| 554 | * @xindex: index into x transition table |
John Johansen | 93c98a4 | 2017-06-09 16:55:04 -0700 | [diff] [blame] | 555 | * @lookupname: returns: name used in lookup if one was specified (NOT NULL) |
Gaosheng Cui | 76426c9d | 2023-06-25 09:13:41 +0800 | [diff] [blame] | 556 | * @info: info message if there was an error (NOT NULL) |
John Johansen | 898127c | 2010-07-29 14:48:06 -0700 | [diff] [blame] | 557 | * |
John Johansen | 93c98a4 | 2017-06-09 16:55:04 -0700 | [diff] [blame] | 558 | * find label for a transition index |
John Johansen | 898127c | 2010-07-29 14:48:06 -0700 | [diff] [blame] | 559 | * |
John Johansen | 93c98a4 | 2017-06-09 16:55:04 -0700 | [diff] [blame] | 560 | * Returns: refcounted label or NULL if not found available |
John Johansen | 898127c | 2010-07-29 14:48:06 -0700 | [diff] [blame] | 561 | */ |
John Johansen | 93c98a4 | 2017-06-09 16:55:04 -0700 | [diff] [blame] | 562 | static struct aa_label *x_to_label(struct aa_profile *profile, |
Matthew Garrett | 8e51f90 | 2018-02-08 12:37:19 -0800 | [diff] [blame] | 563 | const struct linux_binprm *bprm, |
John Johansen | 93c98a4 | 2017-06-09 16:55:04 -0700 | [diff] [blame] | 564 | const char *name, u32 xindex, |
| 565 | const char **lookupname, |
| 566 | const char **info) |
John Johansen | 898127c | 2010-07-29 14:48:06 -0700 | [diff] [blame] | 567 | { |
John Johansen | 1ad22fc | 2022-09-05 20:47:36 -0700 | [diff] [blame] | 568 | struct aa_ruleset *rules = list_first_entry(&profile->rules, |
| 569 | typeof(*rules), list); |
John Johansen | 93c98a4 | 2017-06-09 16:55:04 -0700 | [diff] [blame] | 570 | struct aa_label *new = NULL; |
John Johansen | 98849df | 2017-01-16 00:42:16 -0800 | [diff] [blame] | 571 | struct aa_ns *ns = profile->ns; |
John Johansen | 898127c | 2010-07-29 14:48:06 -0700 | [diff] [blame] | 572 | u32 xtype = xindex & AA_X_TYPE_MASK; |
John Johansen | 93c98a4 | 2017-06-09 16:55:04 -0700 | [diff] [blame] | 573 | const char *stack = NULL; |
John Johansen | 898127c | 2010-07-29 14:48:06 -0700 | [diff] [blame] | 574 | |
| 575 | switch (xtype) { |
| 576 | case AA_X_NONE: |
| 577 | /* fail exec unless ix || ux fallback - handled by caller */ |
John Johansen | 93c98a4 | 2017-06-09 16:55:04 -0700 | [diff] [blame] | 578 | *lookupname = NULL; |
| 579 | break; |
| 580 | case AA_X_TABLE: |
| 581 | /* TODO: fix when perm mapping done at unload */ |
John Johansen | 98b824f | 2023-04-28 05:32:52 -0700 | [diff] [blame] | 582 | stack = rules->file->trans.table[xindex & AA_X_INDEX_MASK]; |
John Johansen | 93c98a4 | 2017-06-09 16:55:04 -0700 | [diff] [blame] | 583 | if (*stack != '&') { |
| 584 | /* released by caller */ |
| 585 | new = x_table_lookup(profile, xindex, lookupname); |
| 586 | stack = NULL; |
| 587 | break; |
| 588 | } |
Gustavo A. R. Silva | df561f66 | 2020-08-23 17:36:59 -0500 | [diff] [blame] | 589 | fallthrough; /* to X_NAME */ |
John Johansen | 898127c | 2010-07-29 14:48:06 -0700 | [diff] [blame] | 590 | case AA_X_NAME: |
| 591 | if (xindex & AA_X_CHILD) |
| 592 | /* released by caller */ |
Matthew Garrett | 8e51f90 | 2018-02-08 12:37:19 -0800 | [diff] [blame] | 593 | new = find_attach(bprm, ns, &profile->base.profiles, |
John Johansen | 844b829 | 2017-11-17 17:42:42 -0800 | [diff] [blame] | 594 | name, info); |
John Johansen | 898127c | 2010-07-29 14:48:06 -0700 | [diff] [blame] | 595 | else |
| 596 | /* released by caller */ |
Matthew Garrett | 8e51f90 | 2018-02-08 12:37:19 -0800 | [diff] [blame] | 597 | new = find_attach(bprm, ns, &ns->base.profiles, |
John Johansen | 844b829 | 2017-11-17 17:42:42 -0800 | [diff] [blame] | 598 | name, info); |
John Johansen | 93c98a4 | 2017-06-09 16:55:04 -0700 | [diff] [blame] | 599 | *lookupname = name; |
John Johansen | 898127c | 2010-07-29 14:48:06 -0700 | [diff] [blame] | 600 | break; |
| 601 | } |
| 602 | |
John Johansen | 93c98a4 | 2017-06-09 16:55:04 -0700 | [diff] [blame] | 603 | if (!new) { |
| 604 | if (xindex & AA_X_INHERIT) { |
| 605 | /* (p|c|n)ix - don't change profile but do |
| 606 | * use the newest version |
| 607 | */ |
| 608 | *info = "ix fallback"; |
| 609 | /* no profile && no error */ |
| 610 | new = aa_get_newest_label(&profile->label); |
| 611 | } else if (xindex & AA_X_UNCONFINED) { |
| 612 | new = aa_get_newest_label(ns_unconfined(profile->ns)); |
| 613 | *info = "ux fallback"; |
| 614 | } |
| 615 | } |
| 616 | |
| 617 | if (new && stack) { |
| 618 | /* base the stack on post domain transition */ |
| 619 | struct aa_label *base = new; |
| 620 | |
Sebastian Andrzej Siewior | 8ac2ca3 | 2019-04-05 15:34:58 +0200 | [diff] [blame] | 621 | new = aa_label_parse(base, stack, GFP_KERNEL, true, false); |
John Johansen | 93c98a4 | 2017-06-09 16:55:04 -0700 | [diff] [blame] | 622 | if (IS_ERR(new)) |
| 623 | new = NULL; |
| 624 | aa_put_label(base); |
| 625 | } |
| 626 | |
John Johansen | 898127c | 2010-07-29 14:48:06 -0700 | [diff] [blame] | 627 | /* released by caller */ |
John Johansen | 93c98a4 | 2017-06-09 16:55:04 -0700 | [diff] [blame] | 628 | return new; |
| 629 | } |
| 630 | |
John Johansen | 90c436a | 2022-09-19 20:48:48 -0700 | [diff] [blame] | 631 | static struct aa_label *profile_transition(const struct cred *subj_cred, |
| 632 | struct aa_profile *profile, |
John Johansen | 93c98a4 | 2017-06-09 16:55:04 -0700 | [diff] [blame] | 633 | const struct linux_binprm *bprm, |
| 634 | char *buffer, struct path_cond *cond, |
| 635 | bool *secure_exec) |
| 636 | { |
John Johansen | 1ad22fc | 2022-09-05 20:47:36 -0700 | [diff] [blame] | 637 | struct aa_ruleset *rules = list_first_entry(&profile->rules, |
| 638 | typeof(*rules), list); |
John Johansen | 93c98a4 | 2017-06-09 16:55:04 -0700 | [diff] [blame] | 639 | struct aa_label *new = NULL; |
| 640 | const char *info = NULL, *name = NULL, *target = NULL; |
John Johansen | 98b824f | 2023-04-28 05:32:52 -0700 | [diff] [blame] | 641 | aa_state_t state = rules->file->start[AA_CLASS_FILE]; |
John Johansen | 93c98a4 | 2017-06-09 16:55:04 -0700 | [diff] [blame] | 642 | struct aa_perms perms = {}; |
| 643 | bool nonewprivs = false; |
| 644 | int error = 0; |
| 645 | |
| 646 | AA_BUG(!profile); |
| 647 | AA_BUG(!bprm); |
| 648 | AA_BUG(!buffer); |
| 649 | |
| 650 | error = aa_path_name(&bprm->file->f_path, profile->path_flags, buffer, |
| 651 | &name, &info, profile->disconnected); |
| 652 | if (error) { |
| 653 | if (profile_unconfined(profile) || |
| 654 | (profile->label.flags & FLAG_IX_ON_NAME_ERROR)) { |
| 655 | AA_DEBUG("name lookup ix on error"); |
| 656 | error = 0; |
| 657 | new = aa_get_newest_label(&profile->label); |
| 658 | } |
| 659 | name = bprm->filename; |
| 660 | goto audit; |
| 661 | } |
| 662 | |
| 663 | if (profile_unconfined(profile)) { |
Matthew Garrett | 8e51f90 | 2018-02-08 12:37:19 -0800 | [diff] [blame] | 664 | new = find_attach(bprm, profile->ns, |
| 665 | &profile->ns->base.profiles, name, &info); |
John Johansen | 93c98a4 | 2017-06-09 16:55:04 -0700 | [diff] [blame] | 666 | if (new) { |
| 667 | AA_DEBUG("unconfined attached to new label"); |
| 668 | return new; |
| 669 | } |
| 670 | AA_DEBUG("unconfined exec no attachment"); |
| 671 | return aa_get_newest_label(&profile->label); |
| 672 | } |
| 673 | |
| 674 | /* find exec permissions for name */ |
John Johansen | 98b824f | 2023-04-28 05:32:52 -0700 | [diff] [blame] | 675 | state = aa_str_perms(rules->file, state, name, cond, &perms); |
John Johansen | 93c98a4 | 2017-06-09 16:55:04 -0700 | [diff] [blame] | 676 | if (perms.allow & MAY_EXEC) { |
| 677 | /* exec permission determine how to transition */ |
Matthew Garrett | 8e51f90 | 2018-02-08 12:37:19 -0800 | [diff] [blame] | 678 | new = x_to_label(profile, bprm, name, perms.xindex, &target, |
| 679 | &info); |
John Johansen | 93c98a4 | 2017-06-09 16:55:04 -0700 | [diff] [blame] | 680 | if (new && new->proxy == profile->label.proxy && info) { |
| 681 | /* hack ix fallback - improve how this is detected */ |
| 682 | goto audit; |
| 683 | } else if (!new) { |
| 684 | error = -EACCES; |
| 685 | info = "profile transition not found"; |
| 686 | /* remove MAY_EXEC to audit as failure */ |
| 687 | perms.allow &= ~MAY_EXEC; |
| 688 | } |
| 689 | } else if (COMPLAIN_MODE(profile)) { |
| 690 | /* no exec permission - learning mode */ |
John Johansen | 5d7c44e | 2017-11-20 22:26:12 -0800 | [diff] [blame] | 691 | struct aa_profile *new_profile = NULL; |
John Johansen | 5d7c44e | 2017-11-20 22:26:12 -0800 | [diff] [blame] | 692 | |
John Johansen | 58f89ce | 2022-10-03 02:48:24 -0700 | [diff] [blame] | 693 | new_profile = aa_new_learning_profile(profile, false, name, |
| 694 | GFP_KERNEL); |
John Johansen | 93c98a4 | 2017-06-09 16:55:04 -0700 | [diff] [blame] | 695 | if (!new_profile) { |
| 696 | error = -ENOMEM; |
| 697 | info = "could not create null profile"; |
| 698 | } else { |
| 699 | error = -EACCES; |
| 700 | new = &new_profile->label; |
| 701 | } |
| 702 | perms.xindex |= AA_X_UNSAFE; |
| 703 | } else |
| 704 | /* fail exec */ |
| 705 | error = -EACCES; |
| 706 | |
| 707 | if (!new) |
| 708 | goto audit; |
| 709 | |
John Johansen | 93c98a4 | 2017-06-09 16:55:04 -0700 | [diff] [blame] | 710 | |
| 711 | if (!(perms.xindex & AA_X_UNSAFE)) { |
| 712 | if (DEBUG_ON) { |
| 713 | dbg_printk("apparmor: scrubbing environment variables" |
| 714 | " for %s profile=", name); |
Sebastian Andrzej Siewior | 8ac2ca3 | 2019-04-05 15:34:58 +0200 | [diff] [blame] | 715 | aa_label_printk(new, GFP_KERNEL); |
John Johansen | 93c98a4 | 2017-06-09 16:55:04 -0700 | [diff] [blame] | 716 | dbg_printk("\n"); |
| 717 | } |
| 718 | *secure_exec = true; |
| 719 | } |
| 720 | |
| 721 | audit: |
John Johansen | 90c436a | 2022-09-19 20:48:48 -0700 | [diff] [blame] | 722 | aa_audit_file(subj_cred, profile, &perms, OP_EXEC, MAY_EXEC, name, |
| 723 | target, new, |
John Johansen | 93c98a4 | 2017-06-09 16:55:04 -0700 | [diff] [blame] | 724 | cond->uid, info, error); |
| 725 | if (!new || nonewprivs) { |
| 726 | aa_put_label(new); |
| 727 | return ERR_PTR(error); |
| 728 | } |
| 729 | |
| 730 | return new; |
| 731 | } |
| 732 | |
John Johansen | 90c436a | 2022-09-19 20:48:48 -0700 | [diff] [blame] | 733 | static int profile_onexec(const struct cred *subj_cred, |
| 734 | struct aa_profile *profile, struct aa_label *onexec, |
John Johansen | 93c98a4 | 2017-06-09 16:55:04 -0700 | [diff] [blame] | 735 | bool stack, const struct linux_binprm *bprm, |
| 736 | char *buffer, struct path_cond *cond, |
| 737 | bool *secure_exec) |
| 738 | { |
John Johansen | 1ad22fc | 2022-09-05 20:47:36 -0700 | [diff] [blame] | 739 | struct aa_ruleset *rules = list_first_entry(&profile->rules, |
| 740 | typeof(*rules), list); |
John Johansen | 98b824f | 2023-04-28 05:32:52 -0700 | [diff] [blame] | 741 | aa_state_t state = rules->file->start[AA_CLASS_FILE]; |
John Johansen | 93c98a4 | 2017-06-09 16:55:04 -0700 | [diff] [blame] | 742 | struct aa_perms perms = {}; |
| 743 | const char *xname = NULL, *info = "change_profile onexec"; |
| 744 | int error = -EACCES; |
| 745 | |
| 746 | AA_BUG(!profile); |
| 747 | AA_BUG(!onexec); |
| 748 | AA_BUG(!bprm); |
| 749 | AA_BUG(!buffer); |
| 750 | |
| 751 | if (profile_unconfined(profile)) { |
| 752 | /* change_profile on exec already granted */ |
| 753 | /* |
| 754 | * NOTE: Domain transitions from unconfined are allowed |
| 755 | * even when no_new_privs is set because this aways results |
| 756 | * in a further reduction of permissions. |
| 757 | */ |
| 758 | return 0; |
| 759 | } |
| 760 | |
| 761 | error = aa_path_name(&bprm->file->f_path, profile->path_flags, buffer, |
| 762 | &xname, &info, profile->disconnected); |
| 763 | if (error) { |
| 764 | if (profile_unconfined(profile) || |
| 765 | (profile->label.flags & FLAG_IX_ON_NAME_ERROR)) { |
| 766 | AA_DEBUG("name lookup ix on error"); |
| 767 | error = 0; |
| 768 | } |
| 769 | xname = bprm->filename; |
| 770 | goto audit; |
| 771 | } |
| 772 | |
| 773 | /* find exec permissions for name */ |
John Johansen | 98b824f | 2023-04-28 05:32:52 -0700 | [diff] [blame] | 774 | state = aa_str_perms(rules->file, state, xname, cond, &perms); |
John Johansen | 93c98a4 | 2017-06-09 16:55:04 -0700 | [diff] [blame] | 775 | if (!(perms.allow & AA_MAY_ONEXEC)) { |
| 776 | info = "no change_onexec valid for executable"; |
| 777 | goto audit; |
| 778 | } |
| 779 | /* test if this exec can be paired with change_profile onexec. |
| 780 | * onexec permission is linked to exec with a standard pairing |
| 781 | * exec\0change_profile |
| 782 | */ |
John Johansen | 98b824f | 2023-04-28 05:32:52 -0700 | [diff] [blame] | 783 | state = aa_dfa_null_transition(rules->file->dfa, state); |
John Johansen | 93c98a4 | 2017-06-09 16:55:04 -0700 | [diff] [blame] | 784 | error = change_profile_perms(profile, onexec, stack, AA_MAY_ONEXEC, |
| 785 | state, &perms); |
| 786 | if (error) { |
| 787 | perms.allow &= ~AA_MAY_ONEXEC; |
| 788 | goto audit; |
| 789 | } |
John Johansen | 93c98a4 | 2017-06-09 16:55:04 -0700 | [diff] [blame] | 790 | |
| 791 | if (!(perms.xindex & AA_X_UNSAFE)) { |
| 792 | if (DEBUG_ON) { |
| 793 | dbg_printk("apparmor: scrubbing environment " |
| 794 | "variables for %s label=", xname); |
Sebastian Andrzej Siewior | 8ac2ca3 | 2019-04-05 15:34:58 +0200 | [diff] [blame] | 795 | aa_label_printk(onexec, GFP_KERNEL); |
John Johansen | 93c98a4 | 2017-06-09 16:55:04 -0700 | [diff] [blame] | 796 | dbg_printk("\n"); |
| 797 | } |
| 798 | *secure_exec = true; |
| 799 | } |
| 800 | |
| 801 | audit: |
John Johansen | 90c436a | 2022-09-19 20:48:48 -0700 | [diff] [blame] | 802 | return aa_audit_file(subj_cred, profile, &perms, OP_EXEC, |
| 803 | AA_MAY_ONEXEC, xname, |
John Johansen | 93c98a4 | 2017-06-09 16:55:04 -0700 | [diff] [blame] | 804 | NULL, onexec, cond->uid, info, error); |
| 805 | } |
| 806 | |
| 807 | /* ensure none ns domain transitions are correctly applied with onexec */ |
| 808 | |
John Johansen | 90c436a | 2022-09-19 20:48:48 -0700 | [diff] [blame] | 809 | static struct aa_label *handle_onexec(const struct cred *subj_cred, |
| 810 | struct aa_label *label, |
John Johansen | 93c98a4 | 2017-06-09 16:55:04 -0700 | [diff] [blame] | 811 | struct aa_label *onexec, bool stack, |
| 812 | const struct linux_binprm *bprm, |
| 813 | char *buffer, struct path_cond *cond, |
| 814 | bool *unsafe) |
| 815 | { |
| 816 | struct aa_profile *profile; |
| 817 | struct aa_label *new; |
| 818 | int error; |
| 819 | |
| 820 | AA_BUG(!label); |
| 821 | AA_BUG(!onexec); |
| 822 | AA_BUG(!bprm); |
| 823 | AA_BUG(!buffer); |
| 824 | |
| 825 | if (!stack) { |
| 826 | error = fn_for_each_in_ns(label, profile, |
John Johansen | 90c436a | 2022-09-19 20:48:48 -0700 | [diff] [blame] | 827 | profile_onexec(subj_cred, profile, onexec, stack, |
John Johansen | 93c98a4 | 2017-06-09 16:55:04 -0700 | [diff] [blame] | 828 | bprm, buffer, cond, unsafe)); |
| 829 | if (error) |
| 830 | return ERR_PTR(error); |
Sebastian Andrzej Siewior | 8ac2ca3 | 2019-04-05 15:34:58 +0200 | [diff] [blame] | 831 | new = fn_label_build_in_ns(label, profile, GFP_KERNEL, |
John Johansen | 93c98a4 | 2017-06-09 16:55:04 -0700 | [diff] [blame] | 832 | aa_get_newest_label(onexec), |
John Johansen | 90c436a | 2022-09-19 20:48:48 -0700 | [diff] [blame] | 833 | profile_transition(subj_cred, profile, bprm, |
| 834 | buffer, |
John Johansen | 93c98a4 | 2017-06-09 16:55:04 -0700 | [diff] [blame] | 835 | cond, unsafe)); |
| 836 | |
| 837 | } else { |
Zygmunt Krynicki | b2c2086 | 2018-04-12 12:34:28 +0200 | [diff] [blame] | 838 | /* TODO: determine how much we want to loosen this */ |
John Johansen | 93c98a4 | 2017-06-09 16:55:04 -0700 | [diff] [blame] | 839 | error = fn_for_each_in_ns(label, profile, |
John Johansen | 90c436a | 2022-09-19 20:48:48 -0700 | [diff] [blame] | 840 | profile_onexec(subj_cred, profile, onexec, stack, bprm, |
John Johansen | 93c98a4 | 2017-06-09 16:55:04 -0700 | [diff] [blame] | 841 | buffer, cond, unsafe)); |
| 842 | if (error) |
| 843 | return ERR_PTR(error); |
Sebastian Andrzej Siewior | 8ac2ca3 | 2019-04-05 15:34:58 +0200 | [diff] [blame] | 844 | new = fn_label_build_in_ns(label, profile, GFP_KERNEL, |
John Johansen | 93c98a4 | 2017-06-09 16:55:04 -0700 | [diff] [blame] | 845 | aa_label_merge(&profile->label, onexec, |
Sebastian Andrzej Siewior | 8ac2ca3 | 2019-04-05 15:34:58 +0200 | [diff] [blame] | 846 | GFP_KERNEL), |
John Johansen | 90c436a | 2022-09-19 20:48:48 -0700 | [diff] [blame] | 847 | profile_transition(subj_cred, profile, bprm, |
| 848 | buffer, |
John Johansen | 93c98a4 | 2017-06-09 16:55:04 -0700 | [diff] [blame] | 849 | cond, unsafe)); |
| 850 | } |
| 851 | |
| 852 | if (new) |
| 853 | return new; |
| 854 | |
| 855 | /* TODO: get rid of GLOBAL_ROOT_UID */ |
| 856 | error = fn_for_each_in_ns(label, profile, |
John Johansen | 90c436a | 2022-09-19 20:48:48 -0700 | [diff] [blame] | 857 | aa_audit_file(subj_cred, profile, &nullperms, |
| 858 | OP_CHANGE_ONEXEC, |
John Johansen | 93c98a4 | 2017-06-09 16:55:04 -0700 | [diff] [blame] | 859 | AA_MAY_ONEXEC, bprm->filename, NULL, |
| 860 | onexec, GLOBAL_ROOT_UID, |
| 861 | "failed to build target label", -ENOMEM)); |
| 862 | return ERR_PTR(error); |
John Johansen | 898127c | 2010-07-29 14:48:06 -0700 | [diff] [blame] | 863 | } |
| 864 | |
| 865 | /** |
Eric W. Biederman | b8bff59 | 2020-03-22 15:46:24 -0500 | [diff] [blame] | 866 | * apparmor_bprm_creds_for_exec - Update the new creds on the bprm struct |
John Johansen | 898127c | 2010-07-29 14:48:06 -0700 | [diff] [blame] | 867 | * @bprm: binprm for the exec (NOT NULL) |
| 868 | * |
| 869 | * Returns: %0 or error on failure |
John Johansen | 93c98a4 | 2017-06-09 16:55:04 -0700 | [diff] [blame] | 870 | * |
| 871 | * TODO: once the other paths are done see if we can't refactor into a fn |
John Johansen | 898127c | 2010-07-29 14:48:06 -0700 | [diff] [blame] | 872 | */ |
Eric W. Biederman | b8bff59 | 2020-03-22 15:46:24 -0500 | [diff] [blame] | 873 | int apparmor_bprm_creds_for_exec(struct linux_binprm *bprm) |
John Johansen | 898127c | 2010-07-29 14:48:06 -0700 | [diff] [blame] | 874 | { |
John Johansen | f175221 | 2017-01-27 04:09:40 -0800 | [diff] [blame] | 875 | struct aa_task_ctx *ctx; |
John Johansen | 93c98a4 | 2017-06-09 16:55:04 -0700 | [diff] [blame] | 876 | struct aa_label *label, *new = NULL; |
John Johansen | 90c436a | 2022-09-19 20:48:48 -0700 | [diff] [blame] | 877 | const struct cred *subj_cred; |
John Johansen | 93c98a4 | 2017-06-09 16:55:04 -0700 | [diff] [blame] | 878 | struct aa_profile *profile; |
John Johansen | 898127c | 2010-07-29 14:48:06 -0700 | [diff] [blame] | 879 | char *buffer = NULL; |
John Johansen | 93c98a4 | 2017-06-09 16:55:04 -0700 | [diff] [blame] | 880 | const char *info = NULL; |
| 881 | int error = 0; |
| 882 | bool unsafe = false; |
Christian Brauner | e67fe63 | 2023-01-13 12:49:30 +0100 | [diff] [blame] | 883 | vfsuid_t vfsuid = i_uid_into_vfsuid(file_mnt_idmap(bprm->file), |
Christian Brauner | 5e26a01 | 2022-06-26 18:06:01 +0200 | [diff] [blame] | 884 | file_inode(bprm->file)); |
John Johansen | 898127c | 2010-07-29 14:48:06 -0700 | [diff] [blame] | 885 | struct path_cond cond = { |
Christian Brauner | 5e26a01 | 2022-06-26 18:06:01 +0200 | [diff] [blame] | 886 | vfsuid_into_kuid(vfsuid), |
Al Viro | 496ad9a | 2013-01-23 17:07:38 -0500 | [diff] [blame] | 887 | file_inode(bprm->file)->i_mode |
John Johansen | 898127c | 2010-07-29 14:48:06 -0700 | [diff] [blame] | 888 | }; |
John Johansen | 898127c | 2010-07-29 14:48:06 -0700 | [diff] [blame] | 889 | |
John Johansen | 90c436a | 2022-09-19 20:48:48 -0700 | [diff] [blame] | 890 | subj_cred = current_cred(); |
John Johansen | de62de5 | 2017-10-08 00:43:02 -0700 | [diff] [blame] | 891 | ctx = task_ctx(current); |
John Johansen | d9087c4 | 2017-01-27 03:53:53 -0800 | [diff] [blame] | 892 | AA_BUG(!cred_label(bprm->cred)); |
John Johansen | f175221 | 2017-01-27 04:09:40 -0800 | [diff] [blame] | 893 | AA_BUG(!ctx); |
John Johansen | 898127c | 2010-07-29 14:48:06 -0700 | [diff] [blame] | 894 | |
John Johansen | d9087c4 | 2017-01-27 03:53:53 -0800 | [diff] [blame] | 895 | label = aa_get_newest_label(cred_label(bprm->cred)); |
John Johansen | 4227c33 | 2017-05-23 03:25:14 -0700 | [diff] [blame] | 896 | |
John Johansen | 9fcf78c | 2017-10-08 18:26:19 -0700 | [diff] [blame] | 897 | /* |
| 898 | * Detect no new privs being set, and store the label it |
| 899 | * occurred under. Ideally this would happen when nnp |
| 900 | * is set but there isn't a good way to do that yet. |
| 901 | * |
| 902 | * Testing for unconfined must be done before the subset test |
| 903 | */ |
| 904 | if ((bprm->unsafe & LSM_UNSAFE_NO_NEW_PRIVS) && !unconfined(label) && |
| 905 | !ctx->nnp) |
| 906 | ctx->nnp = aa_get_label(label); |
| 907 | |
John Johansen | 4227c33 | 2017-05-23 03:25:14 -0700 | [diff] [blame] | 908 | /* buffer freed below, name is pointer into buffer */ |
John Johansen | 341c1fd | 2019-09-14 03:34:06 -0700 | [diff] [blame] | 909 | buffer = aa_get_buffer(false); |
Sebastian Andrzej Siewior | df32333 | 2019-05-03 16:12:21 +0200 | [diff] [blame] | 910 | if (!buffer) { |
| 911 | error = -ENOMEM; |
| 912 | goto done; |
| 913 | } |
| 914 | |
John Johansen | 93c98a4 | 2017-06-09 16:55:04 -0700 | [diff] [blame] | 915 | /* Test for onexec first as onexec override other x transitions. */ |
John Johansen | f175221 | 2017-01-27 04:09:40 -0800 | [diff] [blame] | 916 | if (ctx->onexec) |
John Johansen | 90c436a | 2022-09-19 20:48:48 -0700 | [diff] [blame] | 917 | new = handle_onexec(subj_cred, label, ctx->onexec, ctx->token, |
John Johansen | 93c98a4 | 2017-06-09 16:55:04 -0700 | [diff] [blame] | 918 | bprm, buffer, &cond, &unsafe); |
| 919 | else |
Sebastian Andrzej Siewior | 8ac2ca3 | 2019-04-05 15:34:58 +0200 | [diff] [blame] | 920 | new = fn_label_build(label, profile, GFP_KERNEL, |
John Johansen | 90c436a | 2022-09-19 20:48:48 -0700 | [diff] [blame] | 921 | profile_transition(subj_cred, profile, bprm, |
| 922 | buffer, |
John Johansen | 93c98a4 | 2017-06-09 16:55:04 -0700 | [diff] [blame] | 923 | &cond, &unsafe)); |
John Johansen | 898127c | 2010-07-29 14:48:06 -0700 | [diff] [blame] | 924 | |
John Johansen | 93c98a4 | 2017-06-09 16:55:04 -0700 | [diff] [blame] | 925 | AA_BUG(!new); |
| 926 | if (IS_ERR(new)) { |
| 927 | error = PTR_ERR(new); |
| 928 | goto done; |
| 929 | } else if (!new) { |
| 930 | error = -ENOMEM; |
| 931 | goto done; |
John Johansen | 898127c | 2010-07-29 14:48:06 -0700 | [diff] [blame] | 932 | } |
| 933 | |
John Johansen | 9fcf78c | 2017-10-08 18:26:19 -0700 | [diff] [blame] | 934 | /* Policy has specified a domain transitions. If no_new_privs and |
| 935 | * confined ensure the transition is to confinement that is subset |
| 936 | * of the confinement when the task entered no new privs. |
| 937 | * |
| 938 | * NOTE: Domain transitions from unconfined and to stacked |
| 939 | * subsets are allowed even when no_new_privs is set because this |
| 940 | * aways results in a further reduction of permissions. |
| 941 | */ |
| 942 | if ((bprm->unsafe & LSM_UNSAFE_NO_NEW_PRIVS) && |
John Johansen | 3ed4aaa9 | 2019-09-25 08:02:48 -0700 | [diff] [blame] | 943 | !unconfined(label) && |
| 944 | !aa_label_is_unconfined_subset(new, ctx->nnp)) { |
John Johansen | 9fcf78c | 2017-10-08 18:26:19 -0700 | [diff] [blame] | 945 | error = -EPERM; |
| 946 | info = "no new privs"; |
| 947 | goto audit; |
| 948 | } |
John Johansen | 898127c | 2010-07-29 14:48:06 -0700 | [diff] [blame] | 949 | |
| 950 | if (bprm->unsafe & LSM_UNSAFE_SHARE) { |
| 951 | /* FIXME: currently don't mediate shared state */ |
| 952 | ; |
| 953 | } |
| 954 | |
John Johansen | 93c98a4 | 2017-06-09 16:55:04 -0700 | [diff] [blame] | 955 | if (bprm->unsafe & (LSM_UNSAFE_PTRACE)) { |
| 956 | /* TODO: test needs to be profile of label to new */ |
John Johansen | 90c436a | 2022-09-19 20:48:48 -0700 | [diff] [blame] | 957 | error = may_change_ptraced_domain(bprm->cred, new, &info); |
John Johansen | f7da2de | 2016-04-20 14:18:18 -0700 | [diff] [blame] | 958 | if (error) |
John Johansen | 898127c | 2010-07-29 14:48:06 -0700 | [diff] [blame] | 959 | goto audit; |
John Johansen | 898127c | 2010-07-29 14:48:06 -0700 | [diff] [blame] | 960 | } |
| 961 | |
John Johansen | 93c98a4 | 2017-06-09 16:55:04 -0700 | [diff] [blame] | 962 | if (unsafe) { |
| 963 | if (DEBUG_ON) { |
| 964 | dbg_printk("scrubbing environment variables for %s " |
| 965 | "label=", bprm->filename); |
Sebastian Andrzej Siewior | 8ac2ca3 | 2019-04-05 15:34:58 +0200 | [diff] [blame] | 966 | aa_label_printk(new, GFP_KERNEL); |
John Johansen | 93c98a4 | 2017-06-09 16:55:04 -0700 | [diff] [blame] | 967 | dbg_printk("\n"); |
| 968 | } |
Kees Cook | 993b3ab | 2017-07-18 15:25:24 -0700 | [diff] [blame] | 969 | bprm->secureexec = 1; |
John Johansen | 898127c | 2010-07-29 14:48:06 -0700 | [diff] [blame] | 970 | } |
John Johansen | 898127c | 2010-07-29 14:48:06 -0700 | [diff] [blame] | 971 | |
John Johansen | 93c98a4 | 2017-06-09 16:55:04 -0700 | [diff] [blame] | 972 | if (label->proxy != new->proxy) { |
| 973 | /* when transitioning clear unsafe personality bits */ |
| 974 | if (DEBUG_ON) { |
| 975 | dbg_printk("apparmor: clearing unsafe personality " |
| 976 | "bits. %s label=", bprm->filename); |
Sebastian Andrzej Siewior | 8ac2ca3 | 2019-04-05 15:34:58 +0200 | [diff] [blame] | 977 | aa_label_printk(new, GFP_KERNEL); |
John Johansen | 93c98a4 | 2017-06-09 16:55:04 -0700 | [diff] [blame] | 978 | dbg_printk("\n"); |
| 979 | } |
| 980 | bprm->per_clear |= PER_CLEAR_ON_SETID; |
| 981 | } |
John Johansen | d9087c4 | 2017-01-27 03:53:53 -0800 | [diff] [blame] | 982 | aa_put_label(cred_label(bprm->cred)); |
| 983 | /* transfer reference, released when cred is freed */ |
Casey Schaufler | 69b5a44 | 2018-09-21 17:17:59 -0700 | [diff] [blame] | 984 | set_cred_label(bprm->cred, new); |
John Johansen | 898127c | 2010-07-29 14:48:06 -0700 | [diff] [blame] | 985 | |
John Johansen | 93c98a4 | 2017-06-09 16:55:04 -0700 | [diff] [blame] | 986 | done: |
John Johansen | 637f688 | 2017-06-09 08:14:28 -0700 | [diff] [blame] | 987 | aa_put_label(label); |
Sebastian Andrzej Siewior | df32333 | 2019-05-03 16:12:21 +0200 | [diff] [blame] | 988 | aa_put_buffer(buffer); |
John Johansen | 898127c | 2010-07-29 14:48:06 -0700 | [diff] [blame] | 989 | |
| 990 | return error; |
John Johansen | 93c98a4 | 2017-06-09 16:55:04 -0700 | [diff] [blame] | 991 | |
| 992 | audit: |
| 993 | error = fn_for_each(label, profile, |
John Johansen | 90c436a | 2022-09-19 20:48:48 -0700 | [diff] [blame] | 994 | aa_audit_file(current_cred(), profile, &nullperms, |
| 995 | OP_EXEC, MAY_EXEC, |
John Johansen | 93c98a4 | 2017-06-09 16:55:04 -0700 | [diff] [blame] | 996 | bprm->filename, NULL, new, |
Christian Brauner | 5e26a01 | 2022-06-26 18:06:01 +0200 | [diff] [blame] | 997 | vfsuid_into_kuid(vfsuid), info, error)); |
John Johansen | 93c98a4 | 2017-06-09 16:55:04 -0700 | [diff] [blame] | 998 | aa_put_label(new); |
| 999 | goto done; |
John Johansen | 898127c | 2010-07-29 14:48:06 -0700 | [diff] [blame] | 1000 | } |
| 1001 | |
John Johansen | 898127c | 2010-07-29 14:48:06 -0700 | [diff] [blame] | 1002 | /* |
| 1003 | * Functions for self directed profile change |
| 1004 | */ |
| 1005 | |
John Johansen | 89dbf19 | 2017-06-09 17:01:43 -0700 | [diff] [blame] | 1006 | |
| 1007 | /* helper fn for change_hat |
John Johansen | 898127c | 2010-07-29 14:48:06 -0700 | [diff] [blame] | 1008 | * |
John Johansen | 89dbf19 | 2017-06-09 17:01:43 -0700 | [diff] [blame] | 1009 | * Returns: label for hat transition OR ERR_PTR. Does NOT return NULL |
John Johansen | 898127c | 2010-07-29 14:48:06 -0700 | [diff] [blame] | 1010 | */ |
John Johansen | 90c436a | 2022-09-19 20:48:48 -0700 | [diff] [blame] | 1011 | static struct aa_label *build_change_hat(const struct cred *subj_cred, |
| 1012 | struct aa_profile *profile, |
John Johansen | 89dbf19 | 2017-06-09 17:01:43 -0700 | [diff] [blame] | 1013 | const char *name, bool sibling) |
John Johansen | 898127c | 2010-07-29 14:48:06 -0700 | [diff] [blame] | 1014 | { |
John Johansen | 89dbf19 | 2017-06-09 17:01:43 -0700 | [diff] [blame] | 1015 | struct aa_profile *root, *hat = NULL; |
| 1016 | const char *info = NULL; |
| 1017 | int error = 0; |
| 1018 | |
| 1019 | if (sibling && PROFILE_IS_HAT(profile)) { |
| 1020 | root = aa_get_profile_rcu(&profile->parent); |
| 1021 | } else if (!sibling && !PROFILE_IS_HAT(profile)) { |
| 1022 | root = aa_get_profile(profile); |
| 1023 | } else { |
| 1024 | info = "conflicting target types"; |
| 1025 | error = -EPERM; |
| 1026 | goto audit; |
| 1027 | } |
| 1028 | |
| 1029 | hat = aa_find_child(root, name); |
| 1030 | if (!hat) { |
| 1031 | error = -ENOENT; |
| 1032 | if (COMPLAIN_MODE(profile)) { |
John Johansen | 58f89ce | 2022-10-03 02:48:24 -0700 | [diff] [blame] | 1033 | hat = aa_new_learning_profile(profile, true, name, |
| 1034 | GFP_KERNEL); |
John Johansen | 89dbf19 | 2017-06-09 17:01:43 -0700 | [diff] [blame] | 1035 | if (!hat) { |
| 1036 | info = "failed null profile create"; |
| 1037 | error = -ENOMEM; |
| 1038 | } |
| 1039 | } |
| 1040 | } |
| 1041 | aa_put_profile(root); |
| 1042 | |
| 1043 | audit: |
John Johansen | 90c436a | 2022-09-19 20:48:48 -0700 | [diff] [blame] | 1044 | aa_audit_file(subj_cred, profile, &nullperms, OP_CHANGE_HAT, |
| 1045 | AA_MAY_CHANGEHAT, |
John Johansen | 89dbf19 | 2017-06-09 17:01:43 -0700 | [diff] [blame] | 1046 | name, hat ? hat->base.hname : NULL, |
John Johansen | 24b87a1 | 2018-07-20 03:25:25 -0700 | [diff] [blame] | 1047 | hat ? &hat->label : NULL, GLOBAL_ROOT_UID, info, |
John Johansen | 89dbf19 | 2017-06-09 17:01:43 -0700 | [diff] [blame] | 1048 | error); |
| 1049 | if (!hat || (error && error != -ENOENT)) |
| 1050 | return ERR_PTR(error); |
| 1051 | /* if hat && error - complain mode, already audited and we adjust for |
| 1052 | * complain mode allow by returning hat->label |
| 1053 | */ |
| 1054 | return &hat->label; |
| 1055 | } |
| 1056 | |
| 1057 | /* helper fn for changing into a hat |
| 1058 | * |
| 1059 | * Returns: label for hat transition or ERR_PTR. Does not return NULL |
| 1060 | */ |
John Johansen | 90c436a | 2022-09-19 20:48:48 -0700 | [diff] [blame] | 1061 | static struct aa_label *change_hat(const struct cred *subj_cred, |
| 1062 | struct aa_label *label, const char *hats[], |
John Johansen | 89dbf19 | 2017-06-09 17:01:43 -0700 | [diff] [blame] | 1063 | int count, int flags) |
| 1064 | { |
| 1065 | struct aa_profile *profile, *root, *hat = NULL; |
| 1066 | struct aa_label *new; |
| 1067 | struct label_it it; |
| 1068 | bool sibling = false; |
| 1069 | const char *name, *info = NULL; |
| 1070 | int i, error; |
| 1071 | |
| 1072 | AA_BUG(!label); |
| 1073 | AA_BUG(!hats); |
| 1074 | AA_BUG(count < 1); |
| 1075 | |
| 1076 | if (PROFILE_IS_HAT(labels_profile(label))) |
| 1077 | sibling = true; |
| 1078 | |
| 1079 | /*find first matching hat */ |
| 1080 | for (i = 0; i < count && !hat; i++) { |
| 1081 | name = hats[i]; |
| 1082 | label_for_each_in_ns(it, labels_ns(label), label, profile) { |
| 1083 | if (sibling && PROFILE_IS_HAT(profile)) { |
| 1084 | root = aa_get_profile_rcu(&profile->parent); |
| 1085 | } else if (!sibling && !PROFILE_IS_HAT(profile)) { |
| 1086 | root = aa_get_profile(profile); |
| 1087 | } else { /* conflicting change type */ |
| 1088 | info = "conflicting targets types"; |
| 1089 | error = -EPERM; |
| 1090 | goto fail; |
| 1091 | } |
| 1092 | hat = aa_find_child(root, name); |
| 1093 | aa_put_profile(root); |
| 1094 | if (!hat) { |
| 1095 | if (!COMPLAIN_MODE(profile)) |
| 1096 | goto outer_continue; |
| 1097 | /* complain mode succeed as if hat */ |
| 1098 | } else if (!PROFILE_IS_HAT(hat)) { |
| 1099 | info = "target not hat"; |
| 1100 | error = -EPERM; |
| 1101 | aa_put_profile(hat); |
| 1102 | goto fail; |
| 1103 | } |
| 1104 | aa_put_profile(hat); |
| 1105 | } |
| 1106 | /* found a hat for all profiles in ns */ |
| 1107 | goto build; |
| 1108 | outer_continue: |
| 1109 | ; |
| 1110 | } |
| 1111 | /* no hats that match, find appropriate error |
| 1112 | * |
| 1113 | * In complain mode audit of the failure is based off of the first |
| 1114 | * hat supplied. This is done due how userspace interacts with |
| 1115 | * change_hat. |
| 1116 | */ |
| 1117 | name = NULL; |
| 1118 | label_for_each_in_ns(it, labels_ns(label), label, profile) { |
| 1119 | if (!list_empty(&profile->base.profiles)) { |
| 1120 | info = "hat not found"; |
| 1121 | error = -ENOENT; |
| 1122 | goto fail; |
| 1123 | } |
| 1124 | } |
| 1125 | info = "no hats defined"; |
| 1126 | error = -ECHILD; |
| 1127 | |
| 1128 | fail: |
| 1129 | label_for_each_in_ns(it, labels_ns(label), label, profile) { |
| 1130 | /* |
| 1131 | * no target as it has failed to be found or built |
| 1132 | * |
| 1133 | * change_hat uses probing and should not log failures |
| 1134 | * related to missing hats |
| 1135 | */ |
| 1136 | /* TODO: get rid of GLOBAL_ROOT_UID */ |
| 1137 | if (count > 1 || COMPLAIN_MODE(profile)) { |
John Johansen | 90c436a | 2022-09-19 20:48:48 -0700 | [diff] [blame] | 1138 | aa_audit_file(subj_cred, profile, &nullperms, |
| 1139 | OP_CHANGE_HAT, |
John Johansen | 89dbf19 | 2017-06-09 17:01:43 -0700 | [diff] [blame] | 1140 | AA_MAY_CHANGEHAT, name, NULL, NULL, |
| 1141 | GLOBAL_ROOT_UID, info, error); |
| 1142 | } |
| 1143 | } |
| 1144 | return ERR_PTR(error); |
| 1145 | |
| 1146 | build: |
| 1147 | new = fn_label_build_in_ns(label, profile, GFP_KERNEL, |
John Johansen | 90c436a | 2022-09-19 20:48:48 -0700 | [diff] [blame] | 1148 | build_change_hat(subj_cred, profile, name, |
| 1149 | sibling), |
John Johansen | 89dbf19 | 2017-06-09 17:01:43 -0700 | [diff] [blame] | 1150 | aa_get_label(&profile->label)); |
| 1151 | if (!new) { |
| 1152 | info = "label build failed"; |
| 1153 | error = -ENOMEM; |
| 1154 | goto fail; |
| 1155 | } /* else if (IS_ERR) build_change_hat has logged error so return new */ |
| 1156 | |
| 1157 | return new; |
John Johansen | 898127c | 2010-07-29 14:48:06 -0700 | [diff] [blame] | 1158 | } |
| 1159 | |
| 1160 | /** |
| 1161 | * aa_change_hat - change hat to/from subprofile |
| 1162 | * @hats: vector of hat names to try changing into (MAYBE NULL if @count == 0) |
| 1163 | * @count: number of hat names in @hats |
| 1164 | * @token: magic value to validate the hat change |
John Johansen | df8073c | 2017-06-09 11:36:48 -0700 | [diff] [blame] | 1165 | * @flags: flags affecting behavior of the change |
John Johansen | 898127c | 2010-07-29 14:48:06 -0700 | [diff] [blame] | 1166 | * |
John Johansen | 89dbf19 | 2017-06-09 17:01:43 -0700 | [diff] [blame] | 1167 | * Returns %0 on success, error otherwise. |
| 1168 | * |
John Johansen | 898127c | 2010-07-29 14:48:06 -0700 | [diff] [blame] | 1169 | * Change to the first profile specified in @hats that exists, and store |
| 1170 | * the @hat_magic in the current task context. If the count == 0 and the |
| 1171 | * @token matches that stored in the current task context, return to the |
| 1172 | * top level profile. |
| 1173 | * |
John Johansen | 89dbf19 | 2017-06-09 17:01:43 -0700 | [diff] [blame] | 1174 | * change_hat only applies to profiles in the current ns, and each profile |
| 1175 | * in the ns must make the same transition otherwise change_hat will fail. |
John Johansen | 898127c | 2010-07-29 14:48:06 -0700 | [diff] [blame] | 1176 | */ |
John Johansen | df8073c | 2017-06-09 11:36:48 -0700 | [diff] [blame] | 1177 | int aa_change_hat(const char *hats[], int count, u64 token, int flags) |
John Johansen | 898127c | 2010-07-29 14:48:06 -0700 | [diff] [blame] | 1178 | { |
John Johansen | 90c436a | 2022-09-19 20:48:48 -0700 | [diff] [blame] | 1179 | const struct cred *subj_cred; |
John Johansen | 9fcf78c | 2017-10-08 18:26:19 -0700 | [diff] [blame] | 1180 | struct aa_task_ctx *ctx = task_ctx(current); |
John Johansen | 89dbf19 | 2017-06-09 17:01:43 -0700 | [diff] [blame] | 1181 | struct aa_label *label, *previous, *new = NULL, *target = NULL; |
| 1182 | struct aa_profile *profile; |
John Johansen | 2d679f3 | 2017-05-29 12:19:39 -0700 | [diff] [blame] | 1183 | struct aa_perms perms = {}; |
John Johansen | 89dbf19 | 2017-06-09 17:01:43 -0700 | [diff] [blame] | 1184 | const char *info = NULL; |
John Johansen | 898127c | 2010-07-29 14:48:06 -0700 | [diff] [blame] | 1185 | int error = 0; |
| 1186 | |
| 1187 | /* released below */ |
John Johansen | 90c436a | 2022-09-19 20:48:48 -0700 | [diff] [blame] | 1188 | subj_cred = get_current_cred(); |
| 1189 | label = aa_get_newest_cred_label(subj_cred); |
John Johansen | f175221 | 2017-01-27 04:09:40 -0800 | [diff] [blame] | 1190 | previous = aa_get_newest_label(ctx->previous); |
John Johansen | 898127c | 2010-07-29 14:48:06 -0700 | [diff] [blame] | 1191 | |
John Johansen | 9fcf78c | 2017-10-08 18:26:19 -0700 | [diff] [blame] | 1192 | /* |
| 1193 | * Detect no new privs being set, and store the label it |
| 1194 | * occurred under. Ideally this would happen when nnp |
| 1195 | * is set but there isn't a good way to do that yet. |
| 1196 | * |
| 1197 | * Testing for unconfined must be done before the subset test |
| 1198 | */ |
| 1199 | if (task_no_new_privs(current) && !unconfined(label) && !ctx->nnp) |
| 1200 | ctx->nnp = aa_get_label(label); |
| 1201 | |
John Johansen | 637f688 | 2017-06-09 08:14:28 -0700 | [diff] [blame] | 1202 | if (unconfined(label)) { |
John Johansen | 89dbf19 | 2017-06-09 17:01:43 -0700 | [diff] [blame] | 1203 | info = "unconfined can not change_hat"; |
John Johansen | 898127c | 2010-07-29 14:48:06 -0700 | [diff] [blame] | 1204 | error = -EPERM; |
John Johansen | 89dbf19 | 2017-06-09 17:01:43 -0700 | [diff] [blame] | 1205 | goto fail; |
John Johansen | 898127c | 2010-07-29 14:48:06 -0700 | [diff] [blame] | 1206 | } |
| 1207 | |
| 1208 | if (count) { |
John Johansen | 90c436a | 2022-09-19 20:48:48 -0700 | [diff] [blame] | 1209 | new = change_hat(subj_cred, label, hats, count, flags); |
John Johansen | 89dbf19 | 2017-06-09 17:01:43 -0700 | [diff] [blame] | 1210 | AA_BUG(!new); |
| 1211 | if (IS_ERR(new)) { |
| 1212 | error = PTR_ERR(new); |
| 1213 | new = NULL; |
| 1214 | /* already audited */ |
| 1215 | goto out; |
John Johansen | 898127c | 2010-07-29 14:48:06 -0700 | [diff] [blame] | 1216 | } |
| 1217 | |
John Johansen | 90c436a | 2022-09-19 20:48:48 -0700 | [diff] [blame] | 1218 | /* target cred is the same as current except new label */ |
| 1219 | error = may_change_ptraced_domain(subj_cred, new, &info); |
John Johansen | 89dbf19 | 2017-06-09 17:01:43 -0700 | [diff] [blame] | 1220 | if (error) |
| 1221 | goto fail; |
John Johansen | 898127c | 2010-07-29 14:48:06 -0700 | [diff] [blame] | 1222 | |
John Johansen | 9fcf78c | 2017-10-08 18:26:19 -0700 | [diff] [blame] | 1223 | /* |
| 1224 | * no new privs prevents domain transitions that would |
| 1225 | * reduce restrictions. |
| 1226 | */ |
| 1227 | if (task_no_new_privs(current) && !unconfined(label) && |
John Johansen | 3ed4aaa9 | 2019-09-25 08:02:48 -0700 | [diff] [blame] | 1228 | !aa_label_is_unconfined_subset(new, ctx->nnp)) { |
John Johansen | 9fcf78c | 2017-10-08 18:26:19 -0700 | [diff] [blame] | 1229 | /* not an apparmor denial per se, so don't log it */ |
| 1230 | AA_DEBUG("no_new_privs - change_hat denied"); |
| 1231 | error = -EPERM; |
| 1232 | goto out; |
| 1233 | } |
| 1234 | |
John Johansen | 89dbf19 | 2017-06-09 17:01:43 -0700 | [diff] [blame] | 1235 | if (flags & AA_CHANGE_TEST) |
| 1236 | goto out; |
| 1237 | |
| 1238 | target = new; |
| 1239 | error = aa_set_current_hat(new, token); |
| 1240 | if (error == -EACCES) |
| 1241 | /* kill task in case of brute force attacks */ |
| 1242 | goto kill; |
| 1243 | } else if (previous && !(flags & AA_CHANGE_TEST)) { |
John Johansen | 9fcf78c | 2017-10-08 18:26:19 -0700 | [diff] [blame] | 1244 | /* |
| 1245 | * no new privs prevents domain transitions that would |
| 1246 | * reduce restrictions. |
| 1247 | */ |
| 1248 | if (task_no_new_privs(current) && !unconfined(label) && |
John Johansen | 3ed4aaa9 | 2019-09-25 08:02:48 -0700 | [diff] [blame] | 1249 | !aa_label_is_unconfined_subset(previous, ctx->nnp)) { |
John Johansen | 9fcf78c | 2017-10-08 18:26:19 -0700 | [diff] [blame] | 1250 | /* not an apparmor denial per se, so don't log it */ |
| 1251 | AA_DEBUG("no_new_privs - change_hat denied"); |
| 1252 | error = -EPERM; |
| 1253 | goto out; |
| 1254 | } |
| 1255 | |
John Johansen | 89dbf19 | 2017-06-09 17:01:43 -0700 | [diff] [blame] | 1256 | /* Return to saved label. Kill task if restore fails |
John Johansen | 898127c | 2010-07-29 14:48:06 -0700 | [diff] [blame] | 1257 | * to avoid brute force attacks |
| 1258 | */ |
John Johansen | 89dbf19 | 2017-06-09 17:01:43 -0700 | [diff] [blame] | 1259 | target = previous; |
John Johansen | 637f688 | 2017-06-09 08:14:28 -0700 | [diff] [blame] | 1260 | error = aa_restore_previous_label(token); |
John Johansen | 89dbf19 | 2017-06-09 17:01:43 -0700 | [diff] [blame] | 1261 | if (error) { |
| 1262 | if (error == -EACCES) |
| 1263 | goto kill; |
| 1264 | goto fail; |
| 1265 | } |
| 1266 | } /* else ignore @flags && restores when there is no saved profile */ |
John Johansen | 898127c | 2010-07-29 14:48:06 -0700 | [diff] [blame] | 1267 | |
| 1268 | out: |
John Johansen | 89dbf19 | 2017-06-09 17:01:43 -0700 | [diff] [blame] | 1269 | aa_put_label(new); |
| 1270 | aa_put_label(previous); |
John Johansen | 637f688 | 2017-06-09 08:14:28 -0700 | [diff] [blame] | 1271 | aa_put_label(label); |
John Johansen | 90c436a | 2022-09-19 20:48:48 -0700 | [diff] [blame] | 1272 | put_cred(subj_cred); |
John Johansen | 898127c | 2010-07-29 14:48:06 -0700 | [diff] [blame] | 1273 | |
| 1274 | return error; |
John Johansen | 89dbf19 | 2017-06-09 17:01:43 -0700 | [diff] [blame] | 1275 | |
| 1276 | kill: |
| 1277 | info = "failed token match"; |
| 1278 | perms.kill = AA_MAY_CHANGEHAT; |
| 1279 | |
| 1280 | fail: |
| 1281 | fn_for_each_in_ns(label, profile, |
John Johansen | 90c436a | 2022-09-19 20:48:48 -0700 | [diff] [blame] | 1282 | aa_audit_file(subj_cred, profile, &perms, OP_CHANGE_HAT, |
John Johansen | 89dbf19 | 2017-06-09 17:01:43 -0700 | [diff] [blame] | 1283 | AA_MAY_CHANGEHAT, NULL, NULL, target, |
| 1284 | GLOBAL_ROOT_UID, info, error)); |
| 1285 | |
| 1286 | goto out; |
John Johansen | 898127c | 2010-07-29 14:48:06 -0700 | [diff] [blame] | 1287 | } |
| 1288 | |
John Johansen | 89dbf19 | 2017-06-09 17:01:43 -0700 | [diff] [blame] | 1289 | |
John Johansen | e00b02bb | 2017-06-09 17:07:58 -0700 | [diff] [blame] | 1290 | static int change_profile_perms_wrapper(const char *op, const char *name, |
John Johansen | 90c436a | 2022-09-19 20:48:48 -0700 | [diff] [blame] | 1291 | const struct cred *subj_cred, |
John Johansen | e00b02bb | 2017-06-09 17:07:58 -0700 | [diff] [blame] | 1292 | struct aa_profile *profile, |
| 1293 | struct aa_label *target, bool stack, |
| 1294 | u32 request, struct aa_perms *perms) |
| 1295 | { |
John Johansen | 1ad22fc | 2022-09-05 20:47:36 -0700 | [diff] [blame] | 1296 | struct aa_ruleset *rules = list_first_entry(&profile->rules, |
| 1297 | typeof(*rules), list); |
John Johansen | e00b02bb | 2017-06-09 17:07:58 -0700 | [diff] [blame] | 1298 | const char *info = NULL; |
| 1299 | int error = 0; |
| 1300 | |
John Johansen | e00b02bb | 2017-06-09 17:07:58 -0700 | [diff] [blame] | 1301 | if (!error) |
| 1302 | error = change_profile_perms(profile, target, stack, request, |
John Johansen | 98b824f | 2023-04-28 05:32:52 -0700 | [diff] [blame] | 1303 | rules->file->start[AA_CLASS_FILE], |
John Johansen | 53bdc46 | 2020-11-19 10:37:48 -0800 | [diff] [blame] | 1304 | perms); |
John Johansen | e00b02bb | 2017-06-09 17:07:58 -0700 | [diff] [blame] | 1305 | if (error) |
John Johansen | 90c436a | 2022-09-19 20:48:48 -0700 | [diff] [blame] | 1306 | error = aa_audit_file(subj_cred, profile, perms, op, request, |
| 1307 | name, |
John Johansen | e00b02bb | 2017-06-09 17:07:58 -0700 | [diff] [blame] | 1308 | NULL, target, GLOBAL_ROOT_UID, info, |
| 1309 | error); |
| 1310 | |
| 1311 | return error; |
| 1312 | } |
John Johansen | 89dbf19 | 2017-06-09 17:01:43 -0700 | [diff] [blame] | 1313 | |
John Johansen | 3c49ce0 | 2023-11-09 06:32:28 -0800 | [diff] [blame] | 1314 | static const char *stack_msg = "change_profile unprivileged unconfined converted to stacking"; |
John Johansen | 2d9da9b | 2023-08-09 00:26:36 -0700 | [diff] [blame] | 1315 | |
John Johansen | 898127c | 2010-07-29 14:48:06 -0700 | [diff] [blame] | 1316 | /** |
| 1317 | * aa_change_profile - perform a one-way profile transition |
John Johansen | aa9a39a | 2017-01-16 00:43:06 -0800 | [diff] [blame] | 1318 | * @fqname: name of profile may include namespace (NOT NULL) |
John Johansen | df8073c | 2017-06-09 11:36:48 -0700 | [diff] [blame] | 1319 | * @flags: flags affecting change behavior |
John Johansen | 898127c | 2010-07-29 14:48:06 -0700 | [diff] [blame] | 1320 | * |
| 1321 | * Change to new profile @name. Unlike with hats, there is no way |
| 1322 | * to change back. If @name isn't specified the current profile name is |
| 1323 | * used. |
| 1324 | * If @onexec then the transition is delayed until |
| 1325 | * the next exec. |
| 1326 | * |
| 1327 | * Returns %0 on success, error otherwise. |
| 1328 | */ |
John Johansen | df8073c | 2017-06-09 11:36:48 -0700 | [diff] [blame] | 1329 | int aa_change_profile(const char *fqname, int flags) |
John Johansen | 898127c | 2010-07-29 14:48:06 -0700 | [diff] [blame] | 1330 | { |
John Johansen | e00b02bb | 2017-06-09 17:07:58 -0700 | [diff] [blame] | 1331 | struct aa_label *label, *new = NULL, *target = NULL; |
| 1332 | struct aa_profile *profile; |
John Johansen | 2d679f3 | 2017-05-29 12:19:39 -0700 | [diff] [blame] | 1333 | struct aa_perms perms = {}; |
John Johansen | e00b02bb | 2017-06-09 17:07:58 -0700 | [diff] [blame] | 1334 | const char *info = NULL; |
| 1335 | const char *auditname = fqname; /* retain leading & if stack */ |
| 1336 | bool stack = flags & AA_CHANGE_STACK; |
John Johansen | 9fcf78c | 2017-10-08 18:26:19 -0700 | [diff] [blame] | 1337 | struct aa_task_ctx *ctx = task_ctx(current); |
John Johansen | 90c436a | 2022-09-19 20:48:48 -0700 | [diff] [blame] | 1338 | const struct cred *subj_cred = get_current_cred(); |
John Johansen | 47f6e5c | 2017-01-16 00:43:01 -0800 | [diff] [blame] | 1339 | int error = 0; |
John Johansen | e00b02bb | 2017-06-09 17:07:58 -0700 | [diff] [blame] | 1340 | char *op; |
John Johansen | 898127c | 2010-07-29 14:48:06 -0700 | [diff] [blame] | 1341 | u32 request; |
| 1342 | |
John Johansen | 9fcf78c | 2017-10-08 18:26:19 -0700 | [diff] [blame] | 1343 | label = aa_get_current_label(); |
| 1344 | |
| 1345 | /* |
| 1346 | * Detect no new privs being set, and store the label it |
| 1347 | * occurred under. Ideally this would happen when nnp |
| 1348 | * is set but there isn't a good way to do that yet. |
| 1349 | * |
| 1350 | * Testing for unconfined must be done before the subset test |
| 1351 | */ |
| 1352 | if (task_no_new_privs(current) && !unconfined(label) && !ctx->nnp) |
| 1353 | ctx->nnp = aa_get_label(label); |
| 1354 | |
John Johansen | aa9a39a | 2017-01-16 00:43:06 -0800 | [diff] [blame] | 1355 | if (!fqname || !*fqname) { |
Xiyu Yang | a0b845f | 2020-04-05 13:11:55 +0800 | [diff] [blame] | 1356 | aa_put_label(label); |
John Johansen | aa9a39a | 2017-01-16 00:43:06 -0800 | [diff] [blame] | 1357 | AA_DEBUG("no profile name"); |
John Johansen | 898127c | 2010-07-29 14:48:06 -0700 | [diff] [blame] | 1358 | return -EINVAL; |
John Johansen | aa9a39a | 2017-01-16 00:43:06 -0800 | [diff] [blame] | 1359 | } |
John Johansen | 898127c | 2010-07-29 14:48:06 -0700 | [diff] [blame] | 1360 | |
John Johansen | df8073c | 2017-06-09 11:36:48 -0700 | [diff] [blame] | 1361 | if (flags & AA_CHANGE_ONEXEC) { |
John Johansen | 898127c | 2010-07-29 14:48:06 -0700 | [diff] [blame] | 1362 | request = AA_MAY_ONEXEC; |
John Johansen | e00b02bb | 2017-06-09 17:07:58 -0700 | [diff] [blame] | 1363 | if (stack) |
| 1364 | op = OP_STACK_ONEXEC; |
| 1365 | else |
| 1366 | op = OP_CHANGE_ONEXEC; |
John Johansen | 898127c | 2010-07-29 14:48:06 -0700 | [diff] [blame] | 1367 | } else { |
| 1368 | request = AA_MAY_CHANGE_PROFILE; |
John Johansen | e00b02bb | 2017-06-09 17:07:58 -0700 | [diff] [blame] | 1369 | if (stack) |
| 1370 | op = OP_STACK; |
| 1371 | else |
| 1372 | op = OP_CHANGE_PROFILE; |
John Johansen | 898127c | 2010-07-29 14:48:06 -0700 | [diff] [blame] | 1373 | } |
| 1374 | |
John Johansen | 2d9da9b | 2023-08-09 00:26:36 -0700 | [diff] [blame] | 1375 | /* This should move to a per profile test. Requires pushing build |
| 1376 | * into callback |
| 1377 | */ |
| 1378 | if (!stack && unconfined(label) && |
| 1379 | label == &labels_ns(label)->unconfined->label && |
| 1380 | aa_unprivileged_unconfined_restricted && |
| 1381 | /* TODO: refactor so this check is a fn */ |
| 1382 | cap_capable(current_cred(), &init_user_ns, CAP_MAC_OVERRIDE, |
| 1383 | CAP_OPT_NOAUDIT)) { |
| 1384 | /* regardless of the request in this case apparmor |
| 1385 | * stacks against unconfined so admin set policy can't be |
| 1386 | * by-passed |
| 1387 | */ |
| 1388 | stack = true; |
| 1389 | perms.audit = request; |
| 1390 | (void) fn_for_each_in_ns(label, profile, |
| 1391 | aa_audit_file(subj_cred, profile, &perms, op, |
| 1392 | request, auditname, NULL, target, |
| 1393 | GLOBAL_ROOT_UID, stack_msg, 0)); |
| 1394 | perms.audit = 0; |
| 1395 | } |
| 1396 | |
John Johansen | e00b02bb | 2017-06-09 17:07:58 -0700 | [diff] [blame] | 1397 | if (*fqname == '&') { |
| 1398 | stack = true; |
| 1399 | /* don't have label_parse() do stacking */ |
| 1400 | fqname++; |
John Johansen | c29bceb | 2012-04-12 16:47:51 -0500 | [diff] [blame] | 1401 | } |
John Johansen | e00b02bb | 2017-06-09 17:07:58 -0700 | [diff] [blame] | 1402 | target = aa_label_parse(label, fqname, GFP_KERNEL, true, false); |
| 1403 | if (IS_ERR(target)) { |
| 1404 | struct aa_profile *tprofile; |
John Johansen | c29bceb | 2012-04-12 16:47:51 -0500 | [diff] [blame] | 1405 | |
John Johansen | e00b02bb | 2017-06-09 17:07:58 -0700 | [diff] [blame] | 1406 | info = "label not found"; |
| 1407 | error = PTR_ERR(target); |
| 1408 | target = NULL; |
| 1409 | /* |
| 1410 | * TODO: fixme using labels_profile is not right - do profile |
| 1411 | * per complain profile |
| 1412 | */ |
John Johansen | df8073c | 2017-06-09 11:36:48 -0700 | [diff] [blame] | 1413 | if ((flags & AA_CHANGE_TEST) || |
John Johansen | e00b02bb | 2017-06-09 17:07:58 -0700 | [diff] [blame] | 1414 | !COMPLAIN_MODE(labels_profile(label))) |
John Johansen | 898127c | 2010-07-29 14:48:06 -0700 | [diff] [blame] | 1415 | goto audit; |
| 1416 | /* released below */ |
John Johansen | 58f89ce | 2022-10-03 02:48:24 -0700 | [diff] [blame] | 1417 | tprofile = aa_new_learning_profile(labels_profile(label), false, |
| 1418 | fqname, GFP_KERNEL); |
John Johansen | e00b02bb | 2017-06-09 17:07:58 -0700 | [diff] [blame] | 1419 | if (!tprofile) { |
John Johansen | 898127c | 2010-07-29 14:48:06 -0700 | [diff] [blame] | 1420 | info = "failed null profile create"; |
| 1421 | error = -ENOMEM; |
| 1422 | goto audit; |
| 1423 | } |
John Johansen | e00b02bb | 2017-06-09 17:07:58 -0700 | [diff] [blame] | 1424 | target = &tprofile->label; |
| 1425 | goto check; |
John Johansen | 898127c | 2010-07-29 14:48:06 -0700 | [diff] [blame] | 1426 | } |
| 1427 | |
John Johansen | e00b02bb | 2017-06-09 17:07:58 -0700 | [diff] [blame] | 1428 | /* |
| 1429 | * self directed transitions only apply to current policy ns |
| 1430 | * TODO: currently requiring perms for stacking and straight change |
| 1431 | * stacking doesn't strictly need this. Determine how much |
| 1432 | * we want to loosen this restriction for stacking |
| 1433 | * |
| 1434 | * if (!stack) { |
| 1435 | */ |
| 1436 | error = fn_for_each_in_ns(label, profile, |
| 1437 | change_profile_perms_wrapper(op, auditname, |
John Johansen | 90c436a | 2022-09-19 20:48:48 -0700 | [diff] [blame] | 1438 | subj_cred, |
John Johansen | e00b02bb | 2017-06-09 17:07:58 -0700 | [diff] [blame] | 1439 | profile, target, stack, |
| 1440 | request, &perms)); |
| 1441 | if (error) |
| 1442 | /* auditing done in change_profile_perms_wrapper */ |
| 1443 | goto out; |
John Johansen | aa9a39a | 2017-01-16 00:43:06 -0800 | [diff] [blame] | 1444 | |
John Johansen | e00b02bb | 2017-06-09 17:07:58 -0700 | [diff] [blame] | 1445 | /* } */ |
| 1446 | |
| 1447 | check: |
John Johansen | 898127c | 2010-07-29 14:48:06 -0700 | [diff] [blame] | 1448 | /* check if tracing task is allowed to trace target domain */ |
John Johansen | 90c436a | 2022-09-19 20:48:48 -0700 | [diff] [blame] | 1449 | error = may_change_ptraced_domain(subj_cred, target, &info); |
John Johansen | e00b02bb | 2017-06-09 17:07:58 -0700 | [diff] [blame] | 1450 | if (error && !fn_for_each_in_ns(label, profile, |
| 1451 | COMPLAIN_MODE(profile))) |
John Johansen | 898127c | 2010-07-29 14:48:06 -0700 | [diff] [blame] | 1452 | goto audit; |
John Johansen | 898127c | 2010-07-29 14:48:06 -0700 | [diff] [blame] | 1453 | |
John Johansen | e00b02bb | 2017-06-09 17:07:58 -0700 | [diff] [blame] | 1454 | /* TODO: add permission check to allow this |
| 1455 | * if ((flags & AA_CHANGE_ONEXEC) && !current_is_single_threaded()) { |
| 1456 | * info = "not a single threaded task"; |
| 1457 | * error = -EACCES; |
| 1458 | * goto audit; |
| 1459 | * } |
| 1460 | */ |
John Johansen | df8073c | 2017-06-09 11:36:48 -0700 | [diff] [blame] | 1461 | if (flags & AA_CHANGE_TEST) |
John Johansen | e00b02bb | 2017-06-09 17:07:58 -0700 | [diff] [blame] | 1462 | goto out; |
John Johansen | 898127c | 2010-07-29 14:48:06 -0700 | [diff] [blame] | 1463 | |
John Johansen | 9fcf78c | 2017-10-08 18:26:19 -0700 | [diff] [blame] | 1464 | /* stacking is always a subset, so only check the nonstack case */ |
| 1465 | if (!stack) { |
| 1466 | new = fn_label_build_in_ns(label, profile, GFP_KERNEL, |
| 1467 | aa_get_label(target), |
| 1468 | aa_get_label(&profile->label)); |
| 1469 | /* |
| 1470 | * no new privs prevents domain transitions that would |
| 1471 | * reduce restrictions. |
| 1472 | */ |
| 1473 | if (task_no_new_privs(current) && !unconfined(label) && |
John Johansen | 3ed4aaa9 | 2019-09-25 08:02:48 -0700 | [diff] [blame] | 1474 | !aa_label_is_unconfined_subset(new, ctx->nnp)) { |
John Johansen | 9fcf78c | 2017-10-08 18:26:19 -0700 | [diff] [blame] | 1475 | /* not an apparmor denial per se, so don't log it */ |
| 1476 | AA_DEBUG("no_new_privs - change_hat denied"); |
| 1477 | error = -EPERM; |
| 1478 | goto out; |
| 1479 | } |
| 1480 | } |
| 1481 | |
John Johansen | e00b02bb | 2017-06-09 17:07:58 -0700 | [diff] [blame] | 1482 | if (!(flags & AA_CHANGE_ONEXEC)) { |
| 1483 | /* only transition profiles in the current ns */ |
| 1484 | if (stack) |
| 1485 | new = aa_label_merge(label, target, GFP_KERNEL); |
John Johansen | e00b02bb | 2017-06-09 17:07:58 -0700 | [diff] [blame] | 1486 | if (IS_ERR_OR_NULL(new)) { |
| 1487 | info = "failed to build target label"; |
John Johansen | d6d478ae | 2019-01-24 13:53:05 -0800 | [diff] [blame] | 1488 | if (!new) |
| 1489 | error = -ENOMEM; |
| 1490 | else |
| 1491 | error = PTR_ERR(new); |
John Johansen | e00b02bb | 2017-06-09 17:07:58 -0700 | [diff] [blame] | 1492 | new = NULL; |
| 1493 | perms.allow = 0; |
| 1494 | goto audit; |
| 1495 | } |
| 1496 | error = aa_replace_current_label(new); |
John Johansen | 9fcf78c | 2017-10-08 18:26:19 -0700 | [diff] [blame] | 1497 | } else { |
| 1498 | if (new) { |
| 1499 | aa_put_label(new); |
| 1500 | new = NULL; |
| 1501 | } |
| 1502 | |
John Johansen | e00b02bb | 2017-06-09 17:07:58 -0700 | [diff] [blame] | 1503 | /* full transition will be built in exec path */ |
Quanfa Fu | 0897fcb1 | 2023-01-15 00:49:52 +0800 | [diff] [blame] | 1504 | aa_set_current_onexec(target, stack); |
John Johansen | 9fcf78c | 2017-10-08 18:26:19 -0700 | [diff] [blame] | 1505 | } |
John Johansen | 898127c | 2010-07-29 14:48:06 -0700 | [diff] [blame] | 1506 | |
| 1507 | audit: |
John Johansen | e00b02bb | 2017-06-09 17:07:58 -0700 | [diff] [blame] | 1508 | error = fn_for_each_in_ns(label, profile, |
John Johansen | 90c436a | 2022-09-19 20:48:48 -0700 | [diff] [blame] | 1509 | aa_audit_file(subj_cred, |
| 1510 | profile, &perms, op, request, auditname, |
John Johansen | e00b02bb | 2017-06-09 17:07:58 -0700 | [diff] [blame] | 1511 | NULL, new ? new : target, |
| 1512 | GLOBAL_ROOT_UID, info, error)); |
John Johansen | 898127c | 2010-07-29 14:48:06 -0700 | [diff] [blame] | 1513 | |
John Johansen | e00b02bb | 2017-06-09 17:07:58 -0700 | [diff] [blame] | 1514 | out: |
| 1515 | aa_put_label(new); |
| 1516 | aa_put_label(target); |
John Johansen | 637f688 | 2017-06-09 08:14:28 -0700 | [diff] [blame] | 1517 | aa_put_label(label); |
John Johansen | 90c436a | 2022-09-19 20:48:48 -0700 | [diff] [blame] | 1518 | put_cred(subj_cred); |
John Johansen | 898127c | 2010-07-29 14:48:06 -0700 | [diff] [blame] | 1519 | |
| 1520 | return error; |
| 1521 | } |