Blame view
kernel/seccomp.c
45.6 KB
b24413180
|
1 |
// SPDX-License-Identifier: GPL-2.0 |
1da177e4c
|
2 3 4 5 6 |
/* * linux/kernel/seccomp.c * * Copyright 2004-2005 Andrea Arcangeli <andrea@cpushare.com> * |
e2cfabdfd
|
7 8 9 10 11 12 13 14 |
* Copyright (C) 2012 Google, Inc. * Will Drewry <wad@chromium.org> * * This defines a simple but solid secure-computing facility. * * Mode 1 uses a fixed list of allowed system calls. * Mode 2 allows user-defined system call filters in the form * of Berkeley Packet Filters/Linux Socket Filters. |
1da177e4c
|
15 |
*/ |
0b5fa2290
|
16 |
#include <linux/refcount.h> |
85e7bac33
|
17 |
#include <linux/audit.h> |
5b1017404
|
18 |
#include <linux/compat.h> |
b25e67161
|
19 |
#include <linux/coredump.h> |
8e5f1ad11
|
20 |
#include <linux/kmemleak.h> |
5c3070890
|
21 22 |
#include <linux/nospec.h> #include <linux/prctl.h> |
e2cfabdfd
|
23 |
#include <linux/sched.h> |
68db0cf10
|
24 |
#include <linux/sched/task_stack.h> |
e2cfabdfd
|
25 |
#include <linux/seccomp.h> |
c8bee430d
|
26 |
#include <linux/slab.h> |
48dc92b9f
|
27 |
#include <linux/syscalls.h> |
8e5f1ad11
|
28 |
#include <linux/sysctl.h> |
1da177e4c
|
29 |
|
a4412fc94
|
30 |
#ifdef CONFIG_HAVE_ARCH_SECCOMP_FILTER |
e2cfabdfd
|
31 |
#include <asm/syscall.h> |
a4412fc94
|
32 |
#endif |
e2cfabdfd
|
33 34 |
#ifdef CONFIG_SECCOMP_FILTER |
6a21cc50f
|
35 |
#include <linux/file.h> |
e2cfabdfd
|
36 |
#include <linux/filter.h> |
c2e1f2e30
|
37 |
#include <linux/pid.h> |
fb0fadf9b
|
38 |
#include <linux/ptrace.h> |
e2cfabdfd
|
39 |
#include <linux/security.h> |
e2cfabdfd
|
40 41 |
#include <linux/tracehook.h> #include <linux/uaccess.h> |
6a21cc50f
|
42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 |
#include <linux/anon_inodes.h> enum notify_state { SECCOMP_NOTIFY_INIT, SECCOMP_NOTIFY_SENT, SECCOMP_NOTIFY_REPLIED, }; struct seccomp_knotif { /* The struct pid of the task whose filter triggered the notification */ struct task_struct *task; /* The "cookie" for this request; this is unique for this filter. */ u64 id; /* * The seccomp data. This pointer is valid the entire time this * notification is active, since it comes from __seccomp_filter which * eclipses the entire lifecycle here. */ const struct seccomp_data *data; /* * Notification states. When SECCOMP_RET_USER_NOTIF is returned, a * struct seccomp_knotif is created and starts out in INIT. Once the * handler reads the notification off of an FD, it transitions to SENT. * If a signal is received the state transitions back to INIT and * another message is sent. When the userspace handler replies, state * transitions to REPLIED. */ enum notify_state state; /* The return values, only valid when in SECCOMP_NOTIFY_REPLIED */ int error; long val; /* Signals when this has entered SECCOMP_NOTIFY_REPLIED */ struct completion ready; struct list_head list; }; /** * struct notification - container for seccomp userspace notifications. Since * most seccomp filters will not have notification listeners attached and this * structure is fairly large, we store the notification-specific stuff in a * separate structure. * * @request: A semaphore that users of this notification can wait on for * changes. Actual reads and writes are still controlled with * filter->notify_lock. * @next_id: The id of the next request. * @notifications: A list of struct seccomp_knotif elements. * @wqh: A wait queue for poll. */ struct notification { struct semaphore request; u64 next_id; struct list_head notifications; wait_queue_head_t wqh; }; |
e2cfabdfd
|
103 104 105 106 107 108 109 110 |
/** * struct seccomp_filter - container for seccomp BPF programs * * @usage: reference count to manage the object lifetime. * get/put helpers should be used when accessing an instance * outside of a lifetime-guarded section. In general, this * is only needed for handling filters shared across tasks. |
e66a39977
|
111 |
* @log: true if all actions except for SECCOMP_RET_ALLOW should be logged |
e2cfabdfd
|
112 |
* @prev: points to a previously installed, or inherited, filter |
285fdfc5d
|
113 |
* @prog: the BPF program to evaluate |
6a21cc50f
|
114 115 |
* @notif: the struct that holds all notification related information * @notify_lock: A lock for all notification-related accesses. |
e2cfabdfd
|
116 117 118 119 120 121 122 123 124 125 126 127 |
* * seccomp_filter objects are organized in a tree linked via the @prev * pointer. For any task, it appears to be a singly-linked list starting * with current->seccomp.filter, the most recently attached or inherited filter. * However, multiple filters may share a @prev node, by way of fork(), which * results in a unidirectional tree existing in memory. This is similar to * how namespaces work. * * seccomp_filter objects should never be modified after being attached * to a task_struct (other than @usage). */ struct seccomp_filter { |
0b5fa2290
|
128 |
refcount_t usage; |
e66a39977
|
129 |
bool log; |
e2cfabdfd
|
130 |
struct seccomp_filter *prev; |
7ae457c1e
|
131 |
struct bpf_prog *prog; |
6a21cc50f
|
132 133 |
struct notification *notif; struct mutex notify_lock; |
e2cfabdfd
|
134 135 136 137 |
}; /* Limit any path through the tree to 256KB worth of instructions. */ #define MAX_INSNS_PER_PATH ((1 << 18) / sizeof(struct sock_filter)) |
bd4cf0ed3
|
138 |
/* |
e2cfabdfd
|
139 140 141 |
* Endianness is explicitly ignored and left for BPF program authors to manage * as per the specific architecture. */ |
bd4cf0ed3
|
142 |
static void populate_seccomp_data(struct seccomp_data *sd) |
e2cfabdfd
|
143 |
{ |
bd4cf0ed3
|
144 145 |
struct task_struct *task = current; struct pt_regs *regs = task_pt_regs(task); |
2eac76483
|
146 |
unsigned long args[6]; |
e2cfabdfd
|
147 |
|
bd4cf0ed3
|
148 |
sd->nr = syscall_get_nr(task, regs); |
16add4116
|
149 |
sd->arch = syscall_get_arch(task); |
b35f549df
|
150 |
syscall_get_arguments(task, regs, args); |
2eac76483
|
151 152 153 154 155 156 |
sd->args[0] = args[0]; sd->args[1] = args[1]; sd->args[2] = args[2]; sd->args[3] = args[3]; sd->args[4] = args[4]; sd->args[5] = args[5]; |
bd4cf0ed3
|
157 |
sd->instruction_pointer = KSTK_EIP(task); |
e2cfabdfd
|
158 159 160 161 162 163 164 |
} /** * seccomp_check_filter - verify seccomp filter code * @filter: filter to verify * @flen: length of filter * |
4df95ff48
|
165 |
* Takes a previously checked filter (by bpf_check_classic) and |
e2cfabdfd
|
166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 |
* redirects all filter code that loads struct sk_buff data * and related data through seccomp_bpf_load. It also * enforces length and alignment checking of those loads. * * Returns 0 if the rule set is legal or -EINVAL if not. */ static int seccomp_check_filter(struct sock_filter *filter, unsigned int flen) { int pc; for (pc = 0; pc < flen; pc++) { struct sock_filter *ftest = &filter[pc]; u16 code = ftest->code; u32 k = ftest->k; switch (code) { |
348059313
|
181 |
case BPF_LD | BPF_W | BPF_ABS: |
bd4cf0ed3
|
182 |
ftest->code = BPF_LDX | BPF_W | BPF_ABS; |
e2cfabdfd
|
183 184 185 186 |
/* 32-bit aligned and not out of bounds. */ if (k >= sizeof(struct seccomp_data) || k & 3) return -EINVAL; continue; |
348059313
|
187 |
case BPF_LD | BPF_W | BPF_LEN: |
bd4cf0ed3
|
188 |
ftest->code = BPF_LD | BPF_IMM; |
e2cfabdfd
|
189 190 |
ftest->k = sizeof(struct seccomp_data); continue; |
348059313
|
191 |
case BPF_LDX | BPF_W | BPF_LEN: |
bd4cf0ed3
|
192 |
ftest->code = BPF_LDX | BPF_IMM; |
e2cfabdfd
|
193 194 195 |
ftest->k = sizeof(struct seccomp_data); continue; /* Explicitly include allowed calls. */ |
348059313
|
196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 |
case BPF_RET | BPF_K: case BPF_RET | BPF_A: case BPF_ALU | BPF_ADD | BPF_K: case BPF_ALU | BPF_ADD | BPF_X: case BPF_ALU | BPF_SUB | BPF_K: case BPF_ALU | BPF_SUB | BPF_X: case BPF_ALU | BPF_MUL | BPF_K: case BPF_ALU | BPF_MUL | BPF_X: case BPF_ALU | BPF_DIV | BPF_K: case BPF_ALU | BPF_DIV | BPF_X: case BPF_ALU | BPF_AND | BPF_K: case BPF_ALU | BPF_AND | BPF_X: case BPF_ALU | BPF_OR | BPF_K: case BPF_ALU | BPF_OR | BPF_X: case BPF_ALU | BPF_XOR | BPF_K: case BPF_ALU | BPF_XOR | BPF_X: case BPF_ALU | BPF_LSH | BPF_K: case BPF_ALU | BPF_LSH | BPF_X: case BPF_ALU | BPF_RSH | BPF_K: case BPF_ALU | BPF_RSH | BPF_X: case BPF_ALU | BPF_NEG: case BPF_LD | BPF_IMM: case BPF_LDX | BPF_IMM: case BPF_MISC | BPF_TAX: case BPF_MISC | BPF_TXA: case BPF_LD | BPF_MEM: case BPF_LDX | BPF_MEM: case BPF_ST: case BPF_STX: case BPF_JMP | BPF_JA: case BPF_JMP | BPF_JEQ | BPF_K: case BPF_JMP | BPF_JEQ | BPF_X: case BPF_JMP | BPF_JGE | BPF_K: case BPF_JMP | BPF_JGE | BPF_X: case BPF_JMP | BPF_JGT | BPF_K: case BPF_JMP | BPF_JGT | BPF_X: case BPF_JMP | BPF_JSET | BPF_K: case BPF_JMP | BPF_JSET | BPF_X: |
e2cfabdfd
|
234 235 236 237 238 239 240 241 242 |
continue; default: return -EINVAL; } } return 0; } /** |
285fdfc5d
|
243 244 |
* seccomp_run_filters - evaluates all seccomp filters against @sd * @sd: optional seccomp data to be passed to filters |
deb4de8b3
|
245 246 247 |
* @match: stores struct seccomp_filter that resulted in the return value, * unless filter returned SECCOMP_RET_ALLOW, in which case it will * be unchanged. |
e2cfabdfd
|
248 249 250 |
* * Returns valid seccomp BPF response codes. */ |
0466bdb99
|
251 |
#define ACTION_ONLY(ret) ((s32)((ret) & (SECCOMP_RET_ACTION_FULL))) |
deb4de8b3
|
252 253 |
static u32 seccomp_run_filters(const struct seccomp_data *sd, struct seccomp_filter **match) |
e2cfabdfd
|
254 |
{ |
acf3b2c71
|
255 |
u32 ret = SECCOMP_RET_ALLOW; |
8225d3853
|
256 257 |
/* Make sure cross-thread synced filter points somewhere sane. */ struct seccomp_filter *f = |
506458efa
|
258 |
READ_ONCE(current->seccomp.filter); |
acf3b2c71
|
259 260 |
/* Ensure unexpected behavior doesn't result in failing open. */ |
0d42d73a3
|
261 |
if (WARN_ON(f == NULL)) |
4d3b0b05a
|
262 |
return SECCOMP_RET_KILL_PROCESS; |
acf3b2c71
|
263 |
|
e2cfabdfd
|
264 265 |
/* * All filters in the list are evaluated and the lowest BPF return |
acf3b2c71
|
266 |
* value always takes priority (ignoring the DATA). |
e2cfabdfd
|
267 |
*/ |
e80d02dd7
|
268 |
preempt_disable(); |
3ba2530cc
|
269 |
for (; f; f = f->prev) { |
88575199c
|
270 |
u32 cur_ret = BPF_PROG_RUN(f->prog, sd); |
8f577cadf
|
271 |
|
0466bdb99
|
272 |
if (ACTION_ONLY(cur_ret) < ACTION_ONLY(ret)) { |
acf3b2c71
|
273 |
ret = cur_ret; |
deb4de8b3
|
274 275 |
*match = f; } |
e2cfabdfd
|
276 |
} |
e80d02dd7
|
277 |
preempt_enable(); |
e2cfabdfd
|
278 279 |
return ret; } |
1f41b4504
|
280 |
#endif /* CONFIG_SECCOMP_FILTER */ |
e2cfabdfd
|
281 |
|
1f41b4504
|
282 283 |
static inline bool seccomp_may_assign_mode(unsigned long seccomp_mode) { |
69f6a34bd
|
284 |
assert_spin_locked(¤t->sighand->siglock); |
dbd952127
|
285 |
|
1f41b4504
|
286 287 288 289 290 |
if (current->seccomp.mode && current->seccomp.mode != seccomp_mode) return false; return true; } |
8bf37d8c0
|
291 |
void __weak arch_seccomp_spec_mitigate(struct task_struct *task) { } |
5c3070890
|
292 |
|
3ba2530cc
|
293 |
static inline void seccomp_assign_mode(struct task_struct *task, |
00a02d0c5
|
294 295 |
unsigned long seccomp_mode, unsigned long flags) |
1f41b4504
|
296 |
{ |
69f6a34bd
|
297 |
assert_spin_locked(&task->sighand->siglock); |
dbd952127
|
298 |
|
3ba2530cc
|
299 300 301 302 303 304 |
task->seccomp.mode = seccomp_mode; /* * Make sure TIF_SECCOMP cannot be set before the mode (and * filter) is set. */ smp_mb__before_atomic(); |
00a02d0c5
|
305 306 |
/* Assume default seccomp processes want spec flaw mitigation. */ if ((flags & SECCOMP_FILTER_FLAG_SPEC_ALLOW) == 0) |
8bf37d8c0
|
307 |
arch_seccomp_spec_mitigate(task); |
3ba2530cc
|
308 |
set_tsk_thread_flag(task, TIF_SECCOMP); |
1f41b4504
|
309 310 311 |
} #ifdef CONFIG_SECCOMP_FILTER |
c2e1f2e30
|
312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 |
/* Returns 1 if the parent is an ancestor of the child. */ static int is_ancestor(struct seccomp_filter *parent, struct seccomp_filter *child) { /* NULL is the root ancestor. */ if (parent == NULL) return 1; for (; child; child = child->prev) if (child == parent) return 1; return 0; } /** * seccomp_can_sync_threads: checks if all threads can be synchronized * * Expects sighand and cred_guard_mutex locks to be held. * * Returns 0 on success, -ve on error, or the pid of a thread which was |
6beff00b7
|
331 |
* either not in the correct seccomp mode or did not have an ancestral |
c2e1f2e30
|
332 333 334 335 336 337 338 |
* seccomp filter. */ static inline pid_t seccomp_can_sync_threads(void) { struct task_struct *thread, *caller; BUG_ON(!mutex_is_locked(¤t->signal->cred_guard_mutex)); |
69f6a34bd
|
339 |
assert_spin_locked(¤t->sighand->siglock); |
c2e1f2e30
|
340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 |
/* Validate all threads being eligible for synchronization. */ caller = current; for_each_thread(caller, thread) { pid_t failed; /* Skip current, since it is initiating the sync. */ if (thread == caller) continue; if (thread->seccomp.mode == SECCOMP_MODE_DISABLED || (thread->seccomp.mode == SECCOMP_MODE_FILTER && is_ancestor(thread->seccomp.filter, caller->seccomp.filter))) continue; /* Return the first thread that cannot be synchronized. */ failed = task_pid_vnr(thread); /* If the pid cannot be resolved, then return -ESRCH */ |
0d42d73a3
|
359 |
if (WARN_ON(failed == 0)) |
c2e1f2e30
|
360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 |
failed = -ESRCH; return failed; } return 0; } /** * seccomp_sync_threads: sets all threads to use current's filter * * Expects sighand and cred_guard_mutex locks to be held, and for * seccomp_can_sync_threads() to have returned success already * without dropping the locks. * */ |
00a02d0c5
|
375 |
static inline void seccomp_sync_threads(unsigned long flags) |
c2e1f2e30
|
376 377 378 379 |
{ struct task_struct *thread, *caller; BUG_ON(!mutex_is_locked(¤t->signal->cred_guard_mutex)); |
69f6a34bd
|
380 |
assert_spin_locked(¤t->sighand->siglock); |
c2e1f2e30
|
381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 |
/* Synchronize all threads. */ caller = current; for_each_thread(caller, thread) { /* Skip current, since it needs no changes. */ if (thread == caller) continue; /* Get a task reference for the new leaf node. */ get_seccomp_filter(caller); /* * Drop the task reference to the shared ancestor since * current's path will hold a reference. (This also * allows a put before the assignment.) */ put_seccomp_filter(thread); smp_store_release(&thread->seccomp.filter, caller->seccomp.filter); |
103502a35
|
399 400 401 402 403 404 405 406 407 |
/* * Don't let an unprivileged task work around * the no_new_privs restriction by creating * a thread that sets it up, enters seccomp, * then dies. */ if (task_no_new_privs(caller)) task_set_no_new_privs(thread); |
c2e1f2e30
|
408 409 410 411 412 413 |
/* * Opt the other thread into seccomp if needed. * As threads are considered to be trust-realm * equivalent (see ptrace_may_access), it is safe to * allow one thread to transition the other. */ |
103502a35
|
414 |
if (thread->seccomp.mode == SECCOMP_MODE_DISABLED) |
00a02d0c5
|
415 416 |
seccomp_assign_mode(thread, SECCOMP_MODE_FILTER, flags); |
c2e1f2e30
|
417 418 |
} } |
e2cfabdfd
|
419 |
/** |
c8bee430d
|
420 |
* seccomp_prepare_filter: Prepares a seccomp filter for use. |
e2cfabdfd
|
421 422 |
* @fprog: BPF program to install * |
c8bee430d
|
423 |
* Returns filter on success or an ERR_PTR on failure. |
e2cfabdfd
|
424 |
*/ |
c8bee430d
|
425 |
static struct seccomp_filter *seccomp_prepare_filter(struct sock_fprog *fprog) |
e2cfabdfd
|
426 |
{ |
ac67eb2c5
|
427 428 |
struct seccomp_filter *sfilter; int ret; |
97f2645f3
|
429 |
const bool save_orig = IS_ENABLED(CONFIG_CHECKPOINT_RESTORE); |
e2cfabdfd
|
430 431 |
if (fprog->len == 0 || fprog->len > BPF_MAXINSNS) |
c8bee430d
|
432 |
return ERR_PTR(-EINVAL); |
d9e12f42e
|
433 |
|
c8bee430d
|
434 |
BUG_ON(INT_MAX / fprog->len < sizeof(struct sock_filter)); |
e2cfabdfd
|
435 436 |
/* |
119ce5c8b
|
437 |
* Installing a seccomp filter requires that the task has |
e2cfabdfd
|
438 439 440 441 |
* CAP_SYS_ADMIN in its namespace or be running with no_new_privs. * This avoids scenarios where unprivileged tasks can affect the * behavior of privileged children. */ |
1d4457f99
|
442 |
if (!task_no_new_privs(current) && |
c1a85a00e
|
443 444 |
security_capable(current_cred(), current_user_ns(), CAP_SYS_ADMIN, CAP_OPT_NOAUDIT) != 0) |
c8bee430d
|
445 |
return ERR_PTR(-EACCES); |
e2cfabdfd
|
446 |
|
bd4cf0ed3
|
447 |
/* Allocate a new seccomp_filter */ |
ac67eb2c5
|
448 449 |
sfilter = kzalloc(sizeof(*sfilter), GFP_KERNEL | __GFP_NOWARN); if (!sfilter) |
d9e12f42e
|
450 |
return ERR_PTR(-ENOMEM); |
ac67eb2c5
|
451 |
|
6a21cc50f
|
452 |
mutex_init(&sfilter->notify_lock); |
ac67eb2c5
|
453 |
ret = bpf_prog_create_from_user(&sfilter->prog, fprog, |
f8e529ed9
|
454 |
seccomp_check_filter, save_orig); |
ac67eb2c5
|
455 456 457 |
if (ret < 0) { kfree(sfilter); return ERR_PTR(ret); |
d9e12f42e
|
458 |
} |
bd4cf0ed3
|
459 |
|
0b5fa2290
|
460 |
refcount_set(&sfilter->usage, 1); |
e2cfabdfd
|
461 |
|
ac67eb2c5
|
462 |
return sfilter; |
e2cfabdfd
|
463 464 465 |
} /** |
c8bee430d
|
466 |
* seccomp_prepare_user_filter - prepares a user-supplied sock_fprog |
e2cfabdfd
|
467 468 469 470 |
* @user_filter: pointer to the user data containing a sock_fprog. * * Returns 0 on success and non-zero otherwise. */ |
c8bee430d
|
471 472 |
static struct seccomp_filter * seccomp_prepare_user_filter(const char __user *user_filter) |
e2cfabdfd
|
473 474 |
{ struct sock_fprog fprog; |
c8bee430d
|
475 |
struct seccomp_filter *filter = ERR_PTR(-EFAULT); |
e2cfabdfd
|
476 477 |
#ifdef CONFIG_COMPAT |
5c38065e0
|
478 |
if (in_compat_syscall()) { |
e2cfabdfd
|
479 480 481 482 483 484 485 486 487 |
struct compat_sock_fprog fprog32; if (copy_from_user(&fprog32, user_filter, sizeof(fprog32))) goto out; fprog.len = fprog32.len; fprog.filter = compat_ptr(fprog32.filter); } else /* falls through to the if below. */ #endif if (copy_from_user(&fprog, user_filter, sizeof(fprog))) goto out; |
c8bee430d
|
488 |
filter = seccomp_prepare_filter(&fprog); |
e2cfabdfd
|
489 |
out: |
c8bee430d
|
490 491 492 493 494 495 496 497 |
return filter; } /** * seccomp_attach_filter: validate and attach filter * @flags: flags to change filter behavior * @filter: seccomp filter to add to the current process * |
dbd952127
|
498 499 |
* Caller must be holding current->sighand->siglock lock. * |
7a0df7fbc
|
500 501 502 503 |
* Returns 0 on success, -ve on error, or * - in TSYNC mode: the pid of a thread which was either not in the correct * seccomp mode or did not have an ancestral seccomp filter * - in NEW_LISTENER mode: the fd of the new listener |
c8bee430d
|
504 505 506 507 508 509 |
*/ static long seccomp_attach_filter(unsigned int flags, struct seccomp_filter *filter) { unsigned long total_insns; struct seccomp_filter *walker; |
69f6a34bd
|
510 |
assert_spin_locked(¤t->sighand->siglock); |
dbd952127
|
511 |
|
c8bee430d
|
512 513 514 515 516 517 |
/* Validate resulting filter length. */ total_insns = filter->prog->len; for (walker = current->seccomp.filter; walker; walker = walker->prev) total_insns += walker->prog->len + 4; /* 4 instr penalty */ if (total_insns > MAX_INSNS_PER_PATH) return -ENOMEM; |
c2e1f2e30
|
518 519 520 521 522 523 524 525 |
/* If thread sync has been requested, check that it is possible. */ if (flags & SECCOMP_FILTER_FLAG_TSYNC) { int ret; ret = seccomp_can_sync_threads(); if (ret) return ret; } |
e66a39977
|
526 527 528 |
/* Set log flag, if present. */ if (flags & SECCOMP_FILTER_FLAG_LOG) filter->log = true; |
c8bee430d
|
529 530 531 532 533 534 |
/* * If there is an existing filter, make it the prev and don't drop its * task reference. */ filter->prev = current->seccomp.filter; current->seccomp.filter = filter; |
c2e1f2e30
|
535 536 |
/* Now that the new filter is in place, synchronize to all threads. */ if (flags & SECCOMP_FILTER_FLAG_TSYNC) |
00a02d0c5
|
537 |
seccomp_sync_threads(flags); |
c2e1f2e30
|
538 |
|
c8bee430d
|
539 |
return 0; |
e2cfabdfd
|
540 |
} |
084f5601c
|
541 |
static void __get_seccomp_filter(struct seccomp_filter *filter) |
66a733ea6
|
542 |
{ |
66a733ea6
|
543 544 |
refcount_inc(&filter->usage); } |
e2cfabdfd
|
545 546 547 548 549 550 |
/* get_seccomp_filter - increments the reference count of the filter on @tsk */ void get_seccomp_filter(struct task_struct *tsk) { struct seccomp_filter *orig = tsk->seccomp.filter; if (!orig) return; |
66a733ea6
|
551 |
__get_seccomp_filter(orig); |
e2cfabdfd
|
552 |
} |
c8bee430d
|
553 554 555 |
static inline void seccomp_filter_free(struct seccomp_filter *filter) { if (filter) { |
bab189918
|
556 |
bpf_prog_destroy(filter->prog); |
c8bee430d
|
557 558 559 |
kfree(filter); } } |
66a733ea6
|
560 |
static void __put_seccomp_filter(struct seccomp_filter *orig) |
e2cfabdfd
|
561 |
{ |
e2cfabdfd
|
562 |
/* Clean up single-reference branches iteratively. */ |
0b5fa2290
|
563 |
while (orig && refcount_dec_and_test(&orig->usage)) { |
e2cfabdfd
|
564 565 |
struct seccomp_filter *freeme = orig; orig = orig->prev; |
c8bee430d
|
566 |
seccomp_filter_free(freeme); |
e2cfabdfd
|
567 568 |
} } |
bb6ea4301
|
569 |
|
66a733ea6
|
570 571 572 573 574 |
/* put_seccomp_filter - decrements the ref count of tsk->seccomp.filter */ void put_seccomp_filter(struct task_struct *tsk) { __put_seccomp_filter(tsk->seccomp.filter); } |
ae7795bc6
|
575 |
static void seccomp_init_siginfo(kernel_siginfo_t *info, int syscall, int reason) |
b25e67161
|
576 |
{ |
3b10db2b0
|
577 |
clear_siginfo(info); |
b25e67161
|
578 579 580 581 |
info->si_signo = SIGSYS; info->si_code = SYS_SECCOMP; info->si_call_addr = (void __user *)KSTK_EIP(current); info->si_errno = reason; |
16add4116
|
582 |
info->si_arch = syscall_get_arch(current); |
b25e67161
|
583 584 |
info->si_syscall = syscall; } |
bb6ea4301
|
585 586 587 588 589 590 591 592 593 |
/** * seccomp_send_sigsys - signals the task to allow in-process syscall emulation * @syscall: syscall number to send to userland * @reason: filter-supplied reason code to send to userland (via si_errno) * * Forces a SIGSYS with a code of SYS_SECCOMP and related sigsys info. */ static void seccomp_send_sigsys(int syscall, int reason) { |
ae7795bc6
|
594 |
struct kernel_siginfo info; |
b25e67161
|
595 |
seccomp_init_siginfo(&info, syscall, reason); |
a89e9b8ab
|
596 |
force_sig_info(&info); |
bb6ea4301
|
597 |
} |
e2cfabdfd
|
598 |
#endif /* CONFIG_SECCOMP_FILTER */ |
1da177e4c
|
599 |
|
0ddec0fc8
|
600 |
/* For use with seccomp_actions_logged */ |
4d3b0b05a
|
601 602 |
#define SECCOMP_LOG_KILL_PROCESS (1 << 0) #define SECCOMP_LOG_KILL_THREAD (1 << 1) |
0ddec0fc8
|
603 604 605 |
#define SECCOMP_LOG_TRAP (1 << 2) #define SECCOMP_LOG_ERRNO (1 << 3) #define SECCOMP_LOG_TRACE (1 << 4) |
59f5cf44a
|
606 607 |
#define SECCOMP_LOG_LOG (1 << 5) #define SECCOMP_LOG_ALLOW (1 << 6) |
6a21cc50f
|
608 |
#define SECCOMP_LOG_USER_NOTIF (1 << 7) |
0ddec0fc8
|
609 |
|
4d3b0b05a
|
610 611 |
static u32 seccomp_actions_logged = SECCOMP_LOG_KILL_PROCESS | SECCOMP_LOG_KILL_THREAD | |
fd76875ca
|
612 613 |
SECCOMP_LOG_TRAP | SECCOMP_LOG_ERRNO | |
6a21cc50f
|
614 |
SECCOMP_LOG_USER_NOTIF | |
fd76875ca
|
615 |
SECCOMP_LOG_TRACE | |
59f5cf44a
|
616 |
SECCOMP_LOG_LOG; |
0ddec0fc8
|
617 |
|
e66a39977
|
618 619 |
static inline void seccomp_log(unsigned long syscall, long signr, u32 action, bool requested) |
0ddec0fc8
|
620 621 622 623 624 |
{ bool log = false; switch (action) { case SECCOMP_RET_ALLOW: |
e66a39977
|
625 |
break; |
0ddec0fc8
|
626 |
case SECCOMP_RET_TRAP: |
e66a39977
|
627 628 |
log = requested && seccomp_actions_logged & SECCOMP_LOG_TRAP; break; |
0ddec0fc8
|
629 |
case SECCOMP_RET_ERRNO: |
e66a39977
|
630 631 |
log = requested && seccomp_actions_logged & SECCOMP_LOG_ERRNO; break; |
0ddec0fc8
|
632 |
case SECCOMP_RET_TRACE: |
e66a39977
|
633 |
log = requested && seccomp_actions_logged & SECCOMP_LOG_TRACE; |
0ddec0fc8
|
634 |
break; |
6a21cc50f
|
635 636 637 |
case SECCOMP_RET_USER_NOTIF: log = requested && seccomp_actions_logged & SECCOMP_LOG_USER_NOTIF; break; |
59f5cf44a
|
638 639 640 |
case SECCOMP_RET_LOG: log = seccomp_actions_logged & SECCOMP_LOG_LOG; break; |
fd76875ca
|
641 |
case SECCOMP_RET_KILL_THREAD: |
fd76875ca
|
642 |
log = seccomp_actions_logged & SECCOMP_LOG_KILL_THREAD; |
4d3b0b05a
|
643 644 645 646 |
break; case SECCOMP_RET_KILL_PROCESS: default: log = seccomp_actions_logged & SECCOMP_LOG_KILL_PROCESS; |
0ddec0fc8
|
647 648 649 |
} /* |
326bee028
|
650 651 652 653 |
* Emit an audit message when the action is RET_KILL_*, RET_LOG, or the * FILTER_FLAG_LOG bit was set. The admin has the ability to silence * any action from being logged by removing the action name from the * seccomp_actions_logged sysctl. |
0ddec0fc8
|
654 |
*/ |
326bee028
|
655 656 |
if (!log) return; |
0ddec0fc8
|
657 |
|
326bee028
|
658 |
audit_seccomp(syscall, signr, action); |
0ddec0fc8
|
659 |
} |
1da177e4c
|
660 661 662 663 664 |
/* * Secure computing mode 1 allows only read/write/exit/sigreturn. * To be fully secure this must be combined with rlimit * to limit the stack allocations too. */ |
cb4253aa0
|
665 |
static const int mode1_syscalls[] = { |
1da177e4c
|
666 667 668 |
__NR_seccomp_read, __NR_seccomp_write, __NR_seccomp_exit, __NR_seccomp_sigreturn, 0, /* null terminated */ }; |
a4412fc94
|
669 |
static void __secure_computing_strict(int this_syscall) |
1da177e4c
|
670 |
{ |
cb4253aa0
|
671 |
const int *syscall_whitelist = mode1_syscalls; |
a4412fc94
|
672 |
#ifdef CONFIG_COMPAT |
5c38065e0
|
673 |
if (in_compat_syscall()) |
c983f0e86
|
674 |
syscall_whitelist = get_compat_mode1_syscalls(); |
a4412fc94
|
675 676 677 678 679 680 681 682 683 |
#endif do { if (*syscall_whitelist == this_syscall) return; } while (*++syscall_whitelist); #ifdef SECCOMP_DEBUG dump_stack(); #endif |
fd76875ca
|
684 |
seccomp_log(this_syscall, SIGKILL, SECCOMP_RET_KILL_THREAD, true); |
a4412fc94
|
685 686 687 688 689 690 691 |
do_exit(SIGKILL); } #ifndef CONFIG_HAVE_ARCH_SECCOMP_FILTER void secure_computing_strict(int this_syscall) { int mode = current->seccomp.mode; |
97f2645f3
|
692 |
if (IS_ENABLED(CONFIG_CHECKPOINT_RESTORE) && |
13c4a9011
|
693 694 |
unlikely(current->ptrace & PT_SUSPEND_SECCOMP)) return; |
221272f97
|
695 |
if (mode == SECCOMP_MODE_DISABLED) |
a4412fc94
|
696 697 698 699 700 701 702 |
return; else if (mode == SECCOMP_MODE_STRICT) __secure_computing_strict(this_syscall); else BUG(); } #else |
13aa72f0f
|
703 704 |
#ifdef CONFIG_SECCOMP_FILTER |
6a21cc50f
|
705 706 707 708 709 710 711 712 713 714 715 716 717 718 719 720 721 722 723 724 725 726 727 728 729 730 731 732 733 734 735 736 737 738 739 740 741 742 743 744 745 746 747 748 749 750 751 752 753 754 755 756 757 758 759 760 761 762 763 764 765 |
static u64 seccomp_next_notify_id(struct seccomp_filter *filter) { /* * Note: overflow is ok here, the id just needs to be unique per * filter. */ lockdep_assert_held(&filter->notify_lock); return filter->notif->next_id++; } static void seccomp_do_user_notification(int this_syscall, struct seccomp_filter *match, const struct seccomp_data *sd) { int err; long ret = 0; struct seccomp_knotif n = {}; mutex_lock(&match->notify_lock); err = -ENOSYS; if (!match->notif) goto out; n.task = current; n.state = SECCOMP_NOTIFY_INIT; n.data = sd; n.id = seccomp_next_notify_id(match); init_completion(&n.ready); list_add(&n.list, &match->notif->notifications); up(&match->notif->request); wake_up_poll(&match->notif->wqh, EPOLLIN | EPOLLRDNORM); mutex_unlock(&match->notify_lock); /* * This is where we wait for a reply from userspace. */ err = wait_for_completion_interruptible(&n.ready); mutex_lock(&match->notify_lock); if (err == 0) { ret = n.val; err = n.error; } /* * Note that it's possible the listener died in between the time when * we were notified of a respons (or a signal) and when we were able to * re-acquire the lock, so only delete from the list if the * notification actually exists. * * Also note that this test is only valid because there's no way to * *reattach* to a notifier right now. If one is added, we'll need to * keep track of the notif itself and make sure they match here. */ if (match->notif) list_del(&n.list); out: mutex_unlock(&match->notify_lock); syscall_set_return_value(current, task_pt_regs(current), err, ret); } |
ce6526e8a
|
766 767 |
static int __seccomp_filter(int this_syscall, const struct seccomp_data *sd, const bool recheck_after_trace) |
13aa72f0f
|
768 769 |
{ u32 filter_ret, action; |
deb4de8b3
|
770 |
struct seccomp_filter *match = NULL; |
13aa72f0f
|
771 |
int data; |
db5113911
|
772 |
struct seccomp_data sd_local; |
1da177e4c
|
773 |
|
3ba2530cc
|
774 775 776 777 778 |
/* * Make sure that any changes to mode from another thread have * been seen after TIF_SECCOMP was seen. */ rmb(); |
db5113911
|
779 780 781 782 |
if (!sd) { populate_seccomp_data(&sd_local); sd = &sd_local; } |
deb4de8b3
|
783 |
filter_ret = seccomp_run_filters(sd, &match); |
13aa72f0f
|
784 |
data = filter_ret & SECCOMP_RET_DATA; |
0466bdb99
|
785 |
action = filter_ret & SECCOMP_RET_ACTION_FULL; |
13aa72f0f
|
786 787 788 |
switch (action) { case SECCOMP_RET_ERRNO: |
580c57f10
|
789 790 791 |
/* Set low-order bits as an errno, capped at MAX_ERRNO. */ if (data > MAX_ERRNO) data = MAX_ERRNO; |
d39bd00de
|
792 |
syscall_set_return_value(current, task_pt_regs(current), |
13aa72f0f
|
793 794 795 796 797 |
-data, 0); goto skip; case SECCOMP_RET_TRAP: /* Show the handler the original registers. */ |
d39bd00de
|
798 |
syscall_rollback(current, task_pt_regs(current)); |
13aa72f0f
|
799 800 801 802 803 |
/* Let the filter pass back 16 bits of data. */ seccomp_send_sigsys(this_syscall, data); goto skip; case SECCOMP_RET_TRACE: |
ce6526e8a
|
804 805 806 |
/* We've been put in this state by the ptracer already. */ if (recheck_after_trace) return 0; |
8112c4f14
|
807 808 809 810 811 812 813 814 815 816 817 818 |
/* ENOSYS these calls if there is no tracer attached. */ if (!ptrace_event_enabled(current, PTRACE_EVENT_SECCOMP)) { syscall_set_return_value(current, task_pt_regs(current), -ENOSYS, 0); goto skip; } /* Allow the BPF to provide the event message */ ptrace_event(PTRACE_EVENT_SECCOMP, data); /* * The delivery of a fatal signal during event |
485a252a5
|
819 820 821 822 823 824 825 |
* notification may silently skip tracer notification, * which could leave us with a potentially unmodified * syscall that the tracer would have liked to have * changed. Since the process is about to die, we just * force the syscall to be skipped and let the signal * kill the process and correctly handle any tracer exit * notifications. |
8112c4f14
|
826 827 |
*/ if (fatal_signal_pending(current)) |
485a252a5
|
828 |
goto skip; |
8112c4f14
|
829 830 831 832 |
/* Check if the tracer forced the syscall to be skipped. */ this_syscall = syscall_get_nr(current, task_pt_regs(current)); if (this_syscall < 0) goto skip; |
ce6526e8a
|
833 834 835 836 837 838 839 840 |
/* * Recheck the syscall, since it may have changed. This * intentionally uses a NULL struct seccomp_data to force * a reload of all registers. This does not goto skip since * a skip would have already been reported. */ if (__seccomp_filter(this_syscall, NULL, true)) return -1; |
8112c4f14
|
841 |
return 0; |
13aa72f0f
|
842 |
|
6a21cc50f
|
843 844 845 |
case SECCOMP_RET_USER_NOTIF: seccomp_do_user_notification(this_syscall, match, sd); goto skip; |
59f5cf44a
|
846 847 848 |
case SECCOMP_RET_LOG: seccomp_log(this_syscall, 0, action, true); return 0; |
13aa72f0f
|
849 |
case SECCOMP_RET_ALLOW: |
deb4de8b3
|
850 851 852 853 854 |
/* * Note that the "match" filter will always be NULL for * this action since SECCOMP_RET_ALLOW is the starting * state in seccomp_run_filters(). */ |
8112c4f14
|
855 |
return 0; |
13aa72f0f
|
856 |
|
fd76875ca
|
857 |
case SECCOMP_RET_KILL_THREAD: |
4d3b0b05a
|
858 |
case SECCOMP_RET_KILL_PROCESS: |
131b63515
|
859 |
default: |
e66a39977
|
860 |
seccomp_log(this_syscall, SIGSYS, action, true); |
d7276e321
|
861 |
/* Dump core only if this is the last remaining thread. */ |
4d3b0b05a
|
862 863 |
if (action == SECCOMP_RET_KILL_PROCESS || get_nr_threads(current) == 1) { |
ae7795bc6
|
864 |
kernel_siginfo_t info; |
131b63515
|
865 |
|
d7276e321
|
866 867 868 869 870 871 |
/* Show the original registers in the dump. */ syscall_rollback(current, task_pt_regs(current)); /* Trigger a manual coredump since do_exit skips it. */ seccomp_init_siginfo(&info, this_syscall, data); do_coredump(&info); } |
4d3b0b05a
|
872 873 874 875 |
if (action == SECCOMP_RET_KILL_PROCESS) do_group_exit(SIGSYS); else do_exit(SIGSYS); |
13aa72f0f
|
876 877 878 879 880 |
} unreachable(); skip: |
e66a39977
|
881 |
seccomp_log(this_syscall, 0, action, match ? match->log : false); |
8112c4f14
|
882 883 884 |
return -1; } #else |
ce6526e8a
|
885 886 |
static int __seccomp_filter(int this_syscall, const struct seccomp_data *sd, const bool recheck_after_trace) |
8112c4f14
|
887 888 |
{ BUG(); |
13aa72f0f
|
889 |
} |
1da177e4c
|
890 |
#endif |
13aa72f0f
|
891 |
|
8112c4f14
|
892 |
int __secure_computing(const struct seccomp_data *sd) |
13aa72f0f
|
893 894 |
{ int mode = current->seccomp.mode; |
8112c4f14
|
895 |
int this_syscall; |
13aa72f0f
|
896 |
|
97f2645f3
|
897 |
if (IS_ENABLED(CONFIG_CHECKPOINT_RESTORE) && |
13c4a9011
|
898 |
unlikely(current->ptrace & PT_SUSPEND_SECCOMP)) |
8112c4f14
|
899 900 901 902 |
return 0; this_syscall = sd ? sd->nr : syscall_get_nr(current, task_pt_regs(current)); |
13c4a9011
|
903 |
|
13aa72f0f
|
904 |
switch (mode) { |
e2cfabdfd
|
905 |
case SECCOMP_MODE_STRICT: |
13aa72f0f
|
906 |
__secure_computing_strict(this_syscall); /* may call do_exit */ |
8112c4f14
|
907 |
return 0; |
13aa72f0f
|
908 |
case SECCOMP_MODE_FILTER: |
ce6526e8a
|
909 |
return __seccomp_filter(this_syscall, sd, false); |
1da177e4c
|
910 911 912 |
default: BUG(); } |
13aa72f0f
|
913 |
} |
a4412fc94
|
914 |
#endif /* CONFIG_HAVE_ARCH_SECCOMP_FILTER */ |
1d9d02fee
|
915 916 917 918 919 |
long prctl_get_seccomp(void) { return current->seccomp.mode; } |
e2cfabdfd
|
920 |
/** |
3b23dd128
|
921 |
* seccomp_set_mode_strict: internal function for setting strict seccomp |
e2cfabdfd
|
922 923 924 925 926 |
* * Once current->seccomp.mode is non-zero, it may not be changed. * * Returns 0 on success or -EINVAL on failure. */ |
3b23dd128
|
927 |
static long seccomp_set_mode_strict(void) |
1d9d02fee
|
928 |
{ |
3b23dd128
|
929 |
const unsigned long seccomp_mode = SECCOMP_MODE_STRICT; |
e2cfabdfd
|
930 |
long ret = -EINVAL; |
1d9d02fee
|
931 |
|
dbd952127
|
932 |
spin_lock_irq(¤t->sighand->siglock); |
1f41b4504
|
933 |
if (!seccomp_may_assign_mode(seccomp_mode)) |
1d9d02fee
|
934 |
goto out; |
cf99abace
|
935 |
#ifdef TIF_NOTSC |
3b23dd128
|
936 |
disable_TSC(); |
cf99abace
|
937 |
#endif |
00a02d0c5
|
938 |
seccomp_assign_mode(current, seccomp_mode, 0); |
3b23dd128
|
939 940 941 |
ret = 0; out: |
dbd952127
|
942 |
spin_unlock_irq(¤t->sighand->siglock); |
3b23dd128
|
943 944 945 |
return ret; } |
e2cfabdfd
|
946 |
#ifdef CONFIG_SECCOMP_FILTER |
6a21cc50f
|
947 948 949 950 |
static int seccomp_notify_release(struct inode *inode, struct file *file) { struct seccomp_filter *filter = file->private_data; struct seccomp_knotif *knotif; |
a811dc615
|
951 952 |
if (!filter) return 0; |
6a21cc50f
|
953 954 955 956 957 958 959 960 961 962 963 964 965 966 967 968 969 970 971 972 973 974 975 976 977 978 979 980 981 982 983 984 985 986 987 988 989 990 991 992 993 994 995 996 997 998 999 1000 1001 1002 1003 1004 1005 1006 1007 1008 1009 1010 1011 1012 1013 1014 1015 1016 1017 1018 1019 1020 1021 1022 1023 1024 1025 1026 1027 1028 1029 1030 1031 1032 1033 1034 1035 1036 1037 1038 1039 1040 1041 1042 1043 1044 1045 1046 1047 1048 1049 1050 1051 1052 1053 1054 1055 1056 1057 1058 1059 1060 1061 1062 1063 1064 1065 1066 1067 1068 1069 1070 1071 1072 1073 1074 1075 1076 1077 1078 1079 1080 1081 1082 1083 1084 1085 1086 1087 1088 1089 1090 1091 1092 1093 1094 1095 1096 1097 1098 1099 1100 1101 1102 1103 1104 1105 1106 1107 1108 1109 1110 1111 1112 1113 1114 1115 1116 1117 1118 1119 1120 1121 1122 1123 1124 1125 1126 1127 1128 1129 1130 1131 1132 1133 1134 1135 1136 1137 1138 1139 1140 1141 1142 1143 1144 |
mutex_lock(&filter->notify_lock); /* * If this file is being closed because e.g. the task who owned it * died, let's wake everyone up who was waiting on us. */ list_for_each_entry(knotif, &filter->notif->notifications, list) { if (knotif->state == SECCOMP_NOTIFY_REPLIED) continue; knotif->state = SECCOMP_NOTIFY_REPLIED; knotif->error = -ENOSYS; knotif->val = 0; complete(&knotif->ready); } kfree(filter->notif); filter->notif = NULL; mutex_unlock(&filter->notify_lock); __put_seccomp_filter(filter); return 0; } static long seccomp_notify_recv(struct seccomp_filter *filter, void __user *buf) { struct seccomp_knotif *knotif = NULL, *cur; struct seccomp_notif unotif; ssize_t ret; memset(&unotif, 0, sizeof(unotif)); ret = down_interruptible(&filter->notif->request); if (ret < 0) return ret; mutex_lock(&filter->notify_lock); list_for_each_entry(cur, &filter->notif->notifications, list) { if (cur->state == SECCOMP_NOTIFY_INIT) { knotif = cur; break; } } /* * If we didn't find a notification, it could be that the task was * interrupted by a fatal signal between the time we were woken and * when we were able to acquire the rw lock. */ if (!knotif) { ret = -ENOENT; goto out; } unotif.id = knotif->id; unotif.pid = task_pid_vnr(knotif->task); unotif.data = *(knotif->data); knotif->state = SECCOMP_NOTIFY_SENT; wake_up_poll(&filter->notif->wqh, EPOLLOUT | EPOLLWRNORM); ret = 0; out: mutex_unlock(&filter->notify_lock); if (ret == 0 && copy_to_user(buf, &unotif, sizeof(unotif))) { ret = -EFAULT; /* * Userspace screwed up. To make sure that we keep this * notification alive, let's reset it back to INIT. It * may have died when we released the lock, so we need to make * sure it's still around. */ knotif = NULL; mutex_lock(&filter->notify_lock); list_for_each_entry(cur, &filter->notif->notifications, list) { if (cur->id == unotif.id) { knotif = cur; break; } } if (knotif) { knotif->state = SECCOMP_NOTIFY_INIT; up(&filter->notif->request); } mutex_unlock(&filter->notify_lock); } return ret; } static long seccomp_notify_send(struct seccomp_filter *filter, void __user *buf) { struct seccomp_notif_resp resp = {}; struct seccomp_knotif *knotif = NULL, *cur; long ret; if (copy_from_user(&resp, buf, sizeof(resp))) return -EFAULT; if (resp.flags) return -EINVAL; ret = mutex_lock_interruptible(&filter->notify_lock); if (ret < 0) return ret; list_for_each_entry(cur, &filter->notif->notifications, list) { if (cur->id == resp.id) { knotif = cur; break; } } if (!knotif) { ret = -ENOENT; goto out; } /* Allow exactly one reply. */ if (knotif->state != SECCOMP_NOTIFY_SENT) { ret = -EINPROGRESS; goto out; } ret = 0; knotif->state = SECCOMP_NOTIFY_REPLIED; knotif->error = resp.error; knotif->val = resp.val; complete(&knotif->ready); out: mutex_unlock(&filter->notify_lock); return ret; } static long seccomp_notify_id_valid(struct seccomp_filter *filter, void __user *buf) { struct seccomp_knotif *knotif = NULL; u64 id; long ret; if (copy_from_user(&id, buf, sizeof(id))) return -EFAULT; ret = mutex_lock_interruptible(&filter->notify_lock); if (ret < 0) return ret; ret = -ENOENT; list_for_each_entry(knotif, &filter->notif->notifications, list) { if (knotif->id == id) { if (knotif->state == SECCOMP_NOTIFY_SENT) ret = 0; goto out; } } out: mutex_unlock(&filter->notify_lock); return ret; } static long seccomp_notify_ioctl(struct file *file, unsigned int cmd, unsigned long arg) { struct seccomp_filter *filter = file->private_data; void __user *buf = (void __user *)arg; switch (cmd) { case SECCOMP_IOCTL_NOTIF_RECV: return seccomp_notify_recv(filter, buf); case SECCOMP_IOCTL_NOTIF_SEND: return seccomp_notify_send(filter, buf); case SECCOMP_IOCTL_NOTIF_ID_VALID: return seccomp_notify_id_valid(filter, buf); default: return -EINVAL; } } static __poll_t seccomp_notify_poll(struct file *file, struct poll_table_struct *poll_tab) { struct seccomp_filter *filter = file->private_data; __poll_t ret = 0; struct seccomp_knotif *cur; poll_wait(file, &filter->notif->wqh, poll_tab); |
319deec7d
|
1145 |
if (mutex_lock_interruptible(&filter->notify_lock) < 0) |
6a21cc50f
|
1146 1147 1148 1149 1150 1151 1152 1153 1154 1155 1156 1157 1158 1159 1160 1161 1162 1163 1164 1165 1166 1167 1168 1169 1170 1171 1172 1173 1174 1175 1176 1177 1178 1179 1180 1181 1182 1183 1184 1185 1186 1187 1188 1189 1190 1191 1192 1193 1194 1195 1196 1197 1198 1199 1200 1201 |
return EPOLLERR; list_for_each_entry(cur, &filter->notif->notifications, list) { if (cur->state == SECCOMP_NOTIFY_INIT) ret |= EPOLLIN | EPOLLRDNORM; if (cur->state == SECCOMP_NOTIFY_SENT) ret |= EPOLLOUT | EPOLLWRNORM; if ((ret & EPOLLIN) && (ret & EPOLLOUT)) break; } mutex_unlock(&filter->notify_lock); return ret; } static const struct file_operations seccomp_notify_ops = { .poll = seccomp_notify_poll, .release = seccomp_notify_release, .unlocked_ioctl = seccomp_notify_ioctl, }; static struct file *init_listener(struct seccomp_filter *filter) { struct file *ret = ERR_PTR(-EBUSY); struct seccomp_filter *cur; for (cur = current->seccomp.filter; cur; cur = cur->prev) { if (cur->notif) goto out; } ret = ERR_PTR(-ENOMEM); filter->notif = kzalloc(sizeof(*(filter->notif)), GFP_KERNEL); if (!filter->notif) goto out; sema_init(&filter->notif->request, 0); filter->notif->next_id = get_random_u64(); INIT_LIST_HEAD(&filter->notif->notifications); init_waitqueue_head(&filter->notif->wqh); ret = anon_inode_getfile("seccomp notify", &seccomp_notify_ops, filter, O_RDWR); if (IS_ERR(ret)) goto out_notif; /* The file has a reference to it now */ __get_seccomp_filter(filter); out_notif: if (IS_ERR(ret)) kfree(filter->notif); out: return ret; } |
3b23dd128
|
1202 1203 |
/** * seccomp_set_mode_filter: internal function for setting seccomp filter |
48dc92b9f
|
1204 |
* @flags: flags to change filter behavior |
3b23dd128
|
1205 1206 1207 1208 1209 1210 1211 1212 1213 1214 |
* @filter: struct sock_fprog containing filter * * This function may be called repeatedly to install additional filters. * Every filter successfully installed will be evaluated (in reverse order) * for each system call the task makes. * * Once current->seccomp.mode is non-zero, it may not be changed. * * Returns 0 on success or -EINVAL on failure. */ |
48dc92b9f
|
1215 1216 |
static long seccomp_set_mode_filter(unsigned int flags, const char __user *filter) |
3b23dd128
|
1217 1218 |
{ const unsigned long seccomp_mode = SECCOMP_MODE_FILTER; |
c8bee430d
|
1219 |
struct seccomp_filter *prepared = NULL; |
3b23dd128
|
1220 |
long ret = -EINVAL; |
6a21cc50f
|
1221 1222 |
int listener = -1; struct file *listener_f = NULL; |
3b23dd128
|
1223 |
|
48dc92b9f
|
1224 |
/* Validate flags. */ |
c2e1f2e30
|
1225 |
if (flags & ~SECCOMP_FILTER_FLAG_MASK) |
dbd952127
|
1226 |
return -EINVAL; |
48dc92b9f
|
1227 |
|
7a0df7fbc
|
1228 1229 1230 1231 1232 1233 1234 1235 1236 |
/* * In the successful case, NEW_LISTENER returns the new listener fd. * But in the failure case, TSYNC returns the thread that died. If you * combine these two flags, there's no way to tell whether something * succeeded or failed. So, let's disallow this combination. */ if ((flags & SECCOMP_FILTER_FLAG_TSYNC) && (flags & SECCOMP_FILTER_FLAG_NEW_LISTENER)) return -EINVAL; |
c8bee430d
|
1237 1238 1239 1240 |
/* Prepare the new filter before holding any locks. */ prepared = seccomp_prepare_user_filter(filter); if (IS_ERR(prepared)) return PTR_ERR(prepared); |
6a21cc50f
|
1241 1242 1243 1244 1245 1246 1247 1248 1249 1250 1251 1252 1253 1254 |
if (flags & SECCOMP_FILTER_FLAG_NEW_LISTENER) { listener = get_unused_fd_flags(O_CLOEXEC); if (listener < 0) { ret = listener; goto out_free; } listener_f = init_listener(prepared); if (IS_ERR(listener_f)) { put_unused_fd(listener); ret = PTR_ERR(listener_f); goto out_free; } } |
c2e1f2e30
|
1255 1256 1257 1258 1259 1260 |
/* * Make sure we cannot change seccomp or nnp state via TSYNC * while another thread is in the middle of calling exec. */ if (flags & SECCOMP_FILTER_FLAG_TSYNC && mutex_lock_killable(¤t->signal->cred_guard_mutex)) |
6a21cc50f
|
1261 |
goto out_put_fd; |
c2e1f2e30
|
1262 |
|
dbd952127
|
1263 |
spin_lock_irq(¤t->sighand->siglock); |
3b23dd128
|
1264 1265 |
if (!seccomp_may_assign_mode(seccomp_mode)) goto out; |
c8bee430d
|
1266 |
ret = seccomp_attach_filter(flags, prepared); |
3b23dd128
|
1267 |
if (ret) |
e2cfabdfd
|
1268 |
goto out; |
c8bee430d
|
1269 1270 |
/* Do not free the successfully attached filter. */ prepared = NULL; |
1d9d02fee
|
1271 |
|
00a02d0c5
|
1272 |
seccomp_assign_mode(current, seccomp_mode, flags); |
e2cfabdfd
|
1273 |
out: |
dbd952127
|
1274 |
spin_unlock_irq(¤t->sighand->siglock); |
c2e1f2e30
|
1275 1276 |
if (flags & SECCOMP_FILTER_FLAG_TSYNC) mutex_unlock(¤t->signal->cred_guard_mutex); |
6a21cc50f
|
1277 1278 |
out_put_fd: if (flags & SECCOMP_FILTER_FLAG_NEW_LISTENER) { |
7a0df7fbc
|
1279 |
if (ret) { |
a811dc615
|
1280 |
listener_f->private_data = NULL; |
6a21cc50f
|
1281 1282 1283 1284 1285 1286 1287 |
fput(listener_f); put_unused_fd(listener); } else { fd_install(listener, listener_f); ret = listener; } } |
c2e1f2e30
|
1288 |
out_free: |
c8bee430d
|
1289 |
seccomp_filter_free(prepared); |
1d9d02fee
|
1290 1291 |
return ret; } |
3b23dd128
|
1292 |
#else |
48dc92b9f
|
1293 1294 |
static inline long seccomp_set_mode_filter(unsigned int flags, const char __user *filter) |
3b23dd128
|
1295 1296 1297 1298 |
{ return -EINVAL; } #endif |
d78ab02c2
|
1299 |
|
d612b1fd8
|
1300 1301 1302 1303 1304 1305 1306 1307 |
static long seccomp_get_action_avail(const char __user *uaction) { u32 action; if (copy_from_user(&action, uaction, sizeof(action))) return -EFAULT; switch (action) { |
0466bdb99
|
1308 |
case SECCOMP_RET_KILL_PROCESS: |
fd76875ca
|
1309 |
case SECCOMP_RET_KILL_THREAD: |
d612b1fd8
|
1310 1311 |
case SECCOMP_RET_TRAP: case SECCOMP_RET_ERRNO: |
6a21cc50f
|
1312 |
case SECCOMP_RET_USER_NOTIF: |
d612b1fd8
|
1313 |
case SECCOMP_RET_TRACE: |
59f5cf44a
|
1314 |
case SECCOMP_RET_LOG: |
d612b1fd8
|
1315 1316 1317 1318 1319 1320 1321 1322 |
case SECCOMP_RET_ALLOW: break; default: return -EOPNOTSUPP; } return 0; } |
6a21cc50f
|
1323 1324 1325 1326 1327 1328 1329 1330 1331 1332 1333 1334 1335 |
static long seccomp_get_notif_sizes(void __user *usizes) { struct seccomp_notif_sizes sizes = { .seccomp_notif = sizeof(struct seccomp_notif), .seccomp_notif_resp = sizeof(struct seccomp_notif_resp), .seccomp_data = sizeof(struct seccomp_data), }; if (copy_to_user(usizes, &sizes, sizeof(sizes))) return -EFAULT; return 0; } |
48dc92b9f
|
1336 1337 |
/* Common entry point for both prctl and syscall. */ static long do_seccomp(unsigned int op, unsigned int flags, |
a5662e4d8
|
1338 |
void __user *uargs) |
48dc92b9f
|
1339 1340 1341 1342 1343 1344 1345 1346 |
{ switch (op) { case SECCOMP_SET_MODE_STRICT: if (flags != 0 || uargs != NULL) return -EINVAL; return seccomp_set_mode_strict(); case SECCOMP_SET_MODE_FILTER: return seccomp_set_mode_filter(flags, uargs); |
d612b1fd8
|
1347 1348 1349 1350 1351 |
case SECCOMP_GET_ACTION_AVAIL: if (flags != 0) return -EINVAL; return seccomp_get_action_avail(uargs); |
6a21cc50f
|
1352 1353 1354 1355 1356 |
case SECCOMP_GET_NOTIF_SIZES: if (flags != 0) return -EINVAL; return seccomp_get_notif_sizes(uargs); |
48dc92b9f
|
1357 1358 1359 1360 1361 1362 |
default: return -EINVAL; } } SYSCALL_DEFINE3(seccomp, unsigned int, op, unsigned int, flags, |
a5662e4d8
|
1363 |
void __user *, uargs) |
48dc92b9f
|
1364 1365 1366 |
{ return do_seccomp(op, flags, uargs); } |
d78ab02c2
|
1367 1368 1369 1370 1371 1372 1373 |
/** * prctl_set_seccomp: configures current->seccomp.mode * @seccomp_mode: requested mode to use * @filter: optional struct sock_fprog for use with SECCOMP_MODE_FILTER * * Returns 0 on success or -EINVAL on failure. */ |
a5662e4d8
|
1374 |
long prctl_set_seccomp(unsigned long seccomp_mode, void __user *filter) |
d78ab02c2
|
1375 |
{ |
48dc92b9f
|
1376 |
unsigned int op; |
a5662e4d8
|
1377 |
void __user *uargs; |
48dc92b9f
|
1378 |
|
3b23dd128
|
1379 1380 |
switch (seccomp_mode) { case SECCOMP_MODE_STRICT: |
48dc92b9f
|
1381 1382 1383 1384 1385 1386 1387 1388 |
op = SECCOMP_SET_MODE_STRICT; /* * Setting strict mode through prctl always ignored filter, * so make sure it is always NULL here to pass the internal * check in do_seccomp(). */ uargs = NULL; break; |
3b23dd128
|
1389 |
case SECCOMP_MODE_FILTER: |
48dc92b9f
|
1390 1391 1392 |
op = SECCOMP_SET_MODE_FILTER; uargs = filter; break; |
3b23dd128
|
1393 1394 1395 |
default: return -EINVAL; } |
48dc92b9f
|
1396 1397 1398 |
/* prctl interface doesn't have flags, so they are always zero. */ return do_seccomp(op, 0, uargs); |
d78ab02c2
|
1399 |
} |
f8e529ed9
|
1400 1401 |
#if defined(CONFIG_SECCOMP_FILTER) && defined(CONFIG_CHECKPOINT_RESTORE) |
f06eae831
|
1402 1403 |
static struct seccomp_filter *get_nth_filter(struct task_struct *task, unsigned long filter_off) |
f8e529ed9
|
1404 |
{ |
f06eae831
|
1405 1406 |
struct seccomp_filter *orig, *filter; unsigned long count; |
f8e529ed9
|
1407 |
|
f06eae831
|
1408 1409 1410 1411 |
/* * Note: this is only correct because the caller should be the (ptrace) * tracer of the task, otherwise lock_task_sighand is needed. */ |
f8e529ed9
|
1412 |
spin_lock_irq(&task->sighand->siglock); |
f06eae831
|
1413 |
|
f8e529ed9
|
1414 |
if (task->seccomp.mode != SECCOMP_MODE_FILTER) { |
f06eae831
|
1415 1416 |
spin_unlock_irq(&task->sighand->siglock); return ERR_PTR(-EINVAL); |
f8e529ed9
|
1417 |
} |
f06eae831
|
1418 1419 1420 1421 1422 1423 |
orig = task->seccomp.filter; __get_seccomp_filter(orig); spin_unlock_irq(&task->sighand->siglock); count = 0; for (filter = orig; filter; filter = filter->prev) |
f8e529ed9
|
1424 |
count++; |
f8e529ed9
|
1425 1426 |
if (filter_off >= count) { |
f06eae831
|
1427 |
filter = ERR_PTR(-ENOENT); |
f8e529ed9
|
1428 1429 |
goto out; } |
f8e529ed9
|
1430 |
|
f06eae831
|
1431 1432 |
count -= filter_off; for (filter = orig; filter && count > 1; filter = filter->prev) |
f8e529ed9
|
1433 |
count--; |
f8e529ed9
|
1434 1435 |
if (WARN_ON(count != 1 || !filter)) { |
f06eae831
|
1436 |
filter = ERR_PTR(-ENOENT); |
f8e529ed9
|
1437 1438 |
goto out; } |
f06eae831
|
1439 1440 1441 1442 1443 1444 1445 1446 1447 1448 1449 1450 1451 1452 1453 1454 1455 1456 1457 1458 1459 1460 |
__get_seccomp_filter(filter); out: __put_seccomp_filter(orig); return filter; } long seccomp_get_filter(struct task_struct *task, unsigned long filter_off, void __user *data) { struct seccomp_filter *filter; struct sock_fprog_kern *fprog; long ret; if (!capable(CAP_SYS_ADMIN) || current->seccomp.mode != SECCOMP_MODE_DISABLED) { return -EACCES; } filter = get_nth_filter(task, filter_off); if (IS_ERR(filter)) return PTR_ERR(filter); |
f8e529ed9
|
1461 1462 |
fprog = filter->prog->orig_prog; if (!fprog) { |
470bf1f27
|
1463 |
/* This must be a new non-cBPF filter, since we save |
f8e529ed9
|
1464 1465 1466 1467 1468 1469 1470 1471 1472 1473 |
* every cBPF filter's orig_prog above when * CONFIG_CHECKPOINT_RESTORE is enabled. */ ret = -EMEDIUMTYPE; goto out; } ret = fprog->len; if (!data) goto out; |
f8e529ed9
|
1474 1475 |
if (copy_to_user(data, fprog->filter, bpf_classic_proglen(fprog))) ret = -EFAULT; |
f8e529ed9
|
1476 |
out: |
66a733ea6
|
1477 |
__put_seccomp_filter(filter); |
f8e529ed9
|
1478 |
return ret; |
f8e529ed9
|
1479 |
} |
f8e529ed9
|
1480 |
|
26500475a
|
1481 1482 1483 1484 1485 1486 1487 1488 1489 1490 1491 1492 1493 |
long seccomp_get_metadata(struct task_struct *task, unsigned long size, void __user *data) { long ret; struct seccomp_filter *filter; struct seccomp_metadata kmd = {}; if (!capable(CAP_SYS_ADMIN) || current->seccomp.mode != SECCOMP_MODE_DISABLED) { return -EACCES; } size = min_t(unsigned long, size, sizeof(kmd)); |
63bb0045b
|
1494 1495 1496 1497 |
if (size < sizeof(kmd.filter_off)) return -EINVAL; if (copy_from_user(&kmd.filter_off, data, sizeof(kmd.filter_off))) |
26500475a
|
1498 1499 1500 1501 1502 |
return -EFAULT; filter = get_nth_filter(task, kmd.filter_off); if (IS_ERR(filter)) return PTR_ERR(filter); |
26500475a
|
1503 1504 1505 1506 1507 1508 1509 1510 |
if (filter->log) kmd.flags |= SECCOMP_FILTER_FLAG_LOG; ret = size; if (copy_to_user(data, &kmd, size)) ret = -EFAULT; __put_seccomp_filter(filter); |
f8e529ed9
|
1511 1512 1513 |
return ret; } #endif |
8e5f1ad11
|
1514 1515 1516 1517 |
#ifdef CONFIG_SYSCTL /* Human readable action names for friendly sysctl interaction */ |
0466bdb99
|
1518 |
#define SECCOMP_RET_KILL_PROCESS_NAME "kill_process" |
fd76875ca
|
1519 |
#define SECCOMP_RET_KILL_THREAD_NAME "kill_thread" |
8e5f1ad11
|
1520 1521 |
#define SECCOMP_RET_TRAP_NAME "trap" #define SECCOMP_RET_ERRNO_NAME "errno" |
6a21cc50f
|
1522 |
#define SECCOMP_RET_USER_NOTIF_NAME "user_notif" |
8e5f1ad11
|
1523 |
#define SECCOMP_RET_TRACE_NAME "trace" |
59f5cf44a
|
1524 |
#define SECCOMP_RET_LOG_NAME "log" |
8e5f1ad11
|
1525 |
#define SECCOMP_RET_ALLOW_NAME "allow" |
fd76875ca
|
1526 |
static const char seccomp_actions_avail[] = |
0466bdb99
|
1527 |
SECCOMP_RET_KILL_PROCESS_NAME " " |
fd76875ca
|
1528 1529 1530 |
SECCOMP_RET_KILL_THREAD_NAME " " SECCOMP_RET_TRAP_NAME " " SECCOMP_RET_ERRNO_NAME " " |
6a21cc50f
|
1531 |
SECCOMP_RET_USER_NOTIF_NAME " " |
fd76875ca
|
1532 1533 1534 |
SECCOMP_RET_TRACE_NAME " " SECCOMP_RET_LOG_NAME " " SECCOMP_RET_ALLOW_NAME; |
8e5f1ad11
|
1535 |
|
0ddec0fc8
|
1536 1537 1538 1539 1540 1541 |
struct seccomp_log_name { u32 log; const char *name; }; static const struct seccomp_log_name seccomp_log_names[] = { |
0466bdb99
|
1542 |
{ SECCOMP_LOG_KILL_PROCESS, SECCOMP_RET_KILL_PROCESS_NAME }, |
fd76875ca
|
1543 |
{ SECCOMP_LOG_KILL_THREAD, SECCOMP_RET_KILL_THREAD_NAME }, |
0ddec0fc8
|
1544 1545 |
{ SECCOMP_LOG_TRAP, SECCOMP_RET_TRAP_NAME }, { SECCOMP_LOG_ERRNO, SECCOMP_RET_ERRNO_NAME }, |
6a21cc50f
|
1546 |
{ SECCOMP_LOG_USER_NOTIF, SECCOMP_RET_USER_NOTIF_NAME }, |
0ddec0fc8
|
1547 |
{ SECCOMP_LOG_TRACE, SECCOMP_RET_TRACE_NAME }, |
59f5cf44a
|
1548 |
{ SECCOMP_LOG_LOG, SECCOMP_RET_LOG_NAME }, |
0ddec0fc8
|
1549 1550 1551 1552 1553 |
{ SECCOMP_LOG_ALLOW, SECCOMP_RET_ALLOW_NAME }, { } }; static bool seccomp_names_from_actions_logged(char *names, size_t size, |
beb44acaf
|
1554 1555 |
u32 actions_logged, const char *sep) |
0ddec0fc8
|
1556 1557 |
{ const struct seccomp_log_name *cur; |
beb44acaf
|
1558 |
bool append_sep = false; |
0ddec0fc8
|
1559 1560 1561 1562 1563 1564 |
for (cur = seccomp_log_names; cur->name && size; cur++) { ssize_t ret; if (!(actions_logged & cur->log)) continue; |
beb44acaf
|
1565 1566 |
if (append_sep) { ret = strscpy(names, sep, size); |
0ddec0fc8
|
1567 1568 1569 1570 1571 1572 |
if (ret < 0) return false; names += ret; size -= ret; } else |
beb44acaf
|
1573 |
append_sep = true; |
0ddec0fc8
|
1574 1575 1576 1577 1578 1579 1580 1581 1582 1583 1584 1585 1586 1587 1588 1589 1590 1591 1592 1593 1594 1595 1596 1597 1598 1599 1600 1601 1602 1603 1604 1605 1606 1607 1608 1609 1610 1611 1612 1613 1614 1615 1616 |
ret = strscpy(names, cur->name, size); if (ret < 0) return false; names += ret; size -= ret; } return true; } static bool seccomp_action_logged_from_name(u32 *action_logged, const char *name) { const struct seccomp_log_name *cur; for (cur = seccomp_log_names; cur->name; cur++) { if (!strcmp(cur->name, name)) { *action_logged = cur->log; return true; } } return false; } static bool seccomp_actions_logged_from_names(u32 *actions_logged, char *names) { char *name; *actions_logged = 0; while ((name = strsep(&names, " ")) && *name) { u32 action_logged = 0; if (!seccomp_action_logged_from_name(&action_logged, name)) return false; *actions_logged |= action_logged; } return true; } |
d013db029
|
1617 1618 |
static int read_actions_logged(struct ctl_table *ro_table, void __user *buffer, size_t *lenp, loff_t *ppos) |
0ddec0fc8
|
1619 1620 1621 |
{ char names[sizeof(seccomp_actions_avail)]; struct ctl_table table; |
d013db029
|
1622 1623 1624 1625 |
memset(names, 0, sizeof(names)); if (!seccomp_names_from_actions_logged(names, sizeof(names), |
beb44acaf
|
1626 |
seccomp_actions_logged, " ")) |
d013db029
|
1627 1628 1629 1630 1631 1632 1633 1634 1635 |
return -EINVAL; table = *ro_table; table.data = names; table.maxlen = sizeof(names); return proc_dostring(&table, 0, buffer, lenp, ppos); } static int write_actions_logged(struct ctl_table *ro_table, void __user *buffer, |
ea6eca778
|
1636 |
size_t *lenp, loff_t *ppos, u32 *actions_logged) |
0ddec0fc8
|
1637 1638 1639 1640 |
{ char names[sizeof(seccomp_actions_avail)]; struct ctl_table table; int ret; |
d013db029
|
1641 |
if (!capable(CAP_SYS_ADMIN)) |
0ddec0fc8
|
1642 1643 1644 |
return -EPERM; memset(names, 0, sizeof(names)); |
0ddec0fc8
|
1645 1646 1647 |
table = *ro_table; table.data = names; table.maxlen = sizeof(names); |
d013db029
|
1648 |
ret = proc_dostring(&table, 1, buffer, lenp, ppos); |
0ddec0fc8
|
1649 1650 |
if (ret) return ret; |
ea6eca778
|
1651 |
if (!seccomp_actions_logged_from_names(actions_logged, table.data)) |
d013db029
|
1652 |
return -EINVAL; |
0ddec0fc8
|
1653 |
|
ea6eca778
|
1654 |
if (*actions_logged & SECCOMP_LOG_ALLOW) |
d013db029
|
1655 |
return -EINVAL; |
0ddec0fc8
|
1656 |
|
ea6eca778
|
1657 |
seccomp_actions_logged = *actions_logged; |
0ddec0fc8
|
1658 1659 |
return 0; } |
0ddec0fc8
|
1660 |
|
ea6eca778
|
1661 1662 1663 1664 1665 1666 1667 |
static void audit_actions_logged(u32 actions_logged, u32 old_actions_logged, int ret) { char names[sizeof(seccomp_actions_avail)]; char old_names[sizeof(seccomp_actions_avail)]; const char *new = names; const char *old = old_names; |
0ddec0fc8
|
1668 |
|
ea6eca778
|
1669 1670 1671 1672 1673 1674 1675 1676 1677 1678 1679 1680 1681 1682 1683 1684 1685 1686 1687 1688 1689 1690 1691 |
if (!audit_enabled) return; memset(names, 0, sizeof(names)); memset(old_names, 0, sizeof(old_names)); if (ret) new = "?"; else if (!actions_logged) new = "(none)"; else if (!seccomp_names_from_actions_logged(names, sizeof(names), actions_logged, ",")) new = "?"; if (!old_actions_logged) old = "(none)"; else if (!seccomp_names_from_actions_logged(old_names, sizeof(old_names), old_actions_logged, ",")) old = "?"; return audit_seccomp_actions_logged(new, old, !ret); } |
d013db029
|
1692 1693 1694 1695 |
static int seccomp_actions_logged_handler(struct ctl_table *ro_table, int write, void __user *buffer, size_t *lenp, loff_t *ppos) { |
ea6eca778
|
1696 1697 1698 1699 1700 1701 1702 1703 1704 1705 1706 1707 1708 |
int ret; if (write) { u32 actions_logged = 0; u32 old_actions_logged = seccomp_actions_logged; ret = write_actions_logged(ro_table, buffer, lenp, ppos, &actions_logged); audit_actions_logged(actions_logged, old_actions_logged, ret); } else ret = read_actions_logged(ro_table, buffer, lenp, ppos); return ret; |
0ddec0fc8
|
1709 |
} |
8e5f1ad11
|
1710 1711 1712 1713 1714 1715 1716 1717 1718 1719 1720 1721 1722 1723 |
static struct ctl_path seccomp_sysctl_path[] = { { .procname = "kernel", }, { .procname = "seccomp", }, { } }; static struct ctl_table seccomp_sysctl_table[] = { { .procname = "actions_avail", .data = (void *) &seccomp_actions_avail, .maxlen = sizeof(seccomp_actions_avail), .mode = 0444, .proc_handler = proc_dostring, }, |
0ddec0fc8
|
1724 1725 1726 1727 1728 |
{ .procname = "actions_logged", .mode = 0644, .proc_handler = seccomp_actions_logged_handler, }, |
8e5f1ad11
|
1729 1730 1731 1732 1733 1734 1735 1736 1737 1738 1739 1740 1741 1742 1743 1744 1745 1746 1747 1748 |
{ } }; static int __init seccomp_sysctl_init(void) { struct ctl_table_header *hdr; hdr = register_sysctl_paths(seccomp_sysctl_path, seccomp_sysctl_table); if (!hdr) pr_warn("seccomp: sysctl registration failed "); else kmemleak_not_leak(hdr); return 0; } device_initcall(seccomp_sysctl_init) #endif /* CONFIG_SYSCTL */ |