1 // SPDX-License-Identifier: GPL-2.0
2 #include <linux/kernel.h>
3 #include <linux/errno.h>
4 #include <linux/file.h>
5 #include <linux/io_uring/cmd.h>
6 #include <linux/io_uring/net.h>
7 #include <linux/security.h>
8 #include <linux/nospec.h>
9 #include <net/sock.h>
10
11 #include <uapi/linux/io_uring.h>
12 #include <asm/ioctls.h>
13
14 #include "io_uring.h"
15 #include "alloc_cache.h"
16 #include "rsrc.h"
17 #include "uring_cmd.h"
18
io_uring_async_get(struct io_kiocb * req)19 static struct uring_cache *io_uring_async_get(struct io_kiocb *req)
20 {
21 struct io_ring_ctx *ctx = req->ctx;
22 struct uring_cache *cache;
23
24 cache = io_alloc_cache_get(&ctx->uring_cache);
25 if (cache) {
26 req->flags |= REQ_F_ASYNC_DATA;
27 req->async_data = cache;
28 return cache;
29 }
30 if (!io_alloc_async_data(req))
31 return req->async_data;
32 return NULL;
33 }
34
io_req_uring_cleanup(struct io_kiocb * req,unsigned int issue_flags)35 static void io_req_uring_cleanup(struct io_kiocb *req, unsigned int issue_flags)
36 {
37 struct io_uring_cmd *ioucmd = io_kiocb_to_cmd(req, struct io_uring_cmd);
38 struct uring_cache *cache = req->async_data;
39
40 if (issue_flags & IO_URING_F_UNLOCKED)
41 return;
42 if (io_alloc_cache_put(&req->ctx->uring_cache, cache)) {
43 ioucmd->sqe = NULL;
44 req->async_data = NULL;
45 req->flags &= ~REQ_F_ASYNC_DATA;
46 }
47 }
48
io_uring_try_cancel_uring_cmd(struct io_ring_ctx * ctx,struct io_uring_task * tctx,bool cancel_all)49 bool io_uring_try_cancel_uring_cmd(struct io_ring_ctx *ctx,
50 struct io_uring_task *tctx, bool cancel_all)
51 {
52 struct hlist_node *tmp;
53 struct io_kiocb *req;
54 bool ret = false;
55
56 lockdep_assert_held(&ctx->uring_lock);
57
58 hlist_for_each_entry_safe(req, tmp, &ctx->cancelable_uring_cmd,
59 hash_node) {
60 struct io_uring_cmd *cmd = io_kiocb_to_cmd(req,
61 struct io_uring_cmd);
62 struct file *file = req->file;
63
64 if (!cancel_all && req->tctx != tctx)
65 continue;
66
67 if (cmd->flags & IORING_URING_CMD_CANCELABLE) {
68 /* ->sqe isn't available if no async data */
69 if (!req_has_async_data(req))
70 cmd->sqe = NULL;
71 file->f_op->uring_cmd(cmd, IO_URING_F_CANCEL |
72 IO_URING_F_COMPLETE_DEFER);
73 ret = true;
74 }
75 }
76 io_submit_flush_completions(ctx);
77 return ret;
78 }
79
io_uring_cmd_del_cancelable(struct io_uring_cmd * cmd,unsigned int issue_flags)80 static void io_uring_cmd_del_cancelable(struct io_uring_cmd *cmd,
81 unsigned int issue_flags)
82 {
83 struct io_kiocb *req = cmd_to_io_kiocb(cmd);
84 struct io_ring_ctx *ctx = req->ctx;
85
86 if (!(cmd->flags & IORING_URING_CMD_CANCELABLE))
87 return;
88
89 cmd->flags &= ~IORING_URING_CMD_CANCELABLE;
90 io_ring_submit_lock(ctx, issue_flags);
91 hlist_del(&req->hash_node);
92 io_ring_submit_unlock(ctx, issue_flags);
93 }
94
95 /*
96 * Mark this command as concelable, then io_uring_try_cancel_uring_cmd()
97 * will try to cancel this issued command by sending ->uring_cmd() with
98 * issue_flags of IO_URING_F_CANCEL.
99 *
100 * The command is guaranteed to not be done when calling ->uring_cmd()
101 * with IO_URING_F_CANCEL, but it is driver's responsibility to deal
102 * with race between io_uring canceling and normal completion.
103 */
io_uring_cmd_mark_cancelable(struct io_uring_cmd * cmd,unsigned int issue_flags)104 void io_uring_cmd_mark_cancelable(struct io_uring_cmd *cmd,
105 unsigned int issue_flags)
106 {
107 struct io_kiocb *req = cmd_to_io_kiocb(cmd);
108 struct io_ring_ctx *ctx = req->ctx;
109
110 if (!(cmd->flags & IORING_URING_CMD_CANCELABLE)) {
111 cmd->flags |= IORING_URING_CMD_CANCELABLE;
112 io_ring_submit_lock(ctx, issue_flags);
113 hlist_add_head(&req->hash_node, &ctx->cancelable_uring_cmd);
114 io_ring_submit_unlock(ctx, issue_flags);
115 }
116 }
117 EXPORT_SYMBOL_GPL(io_uring_cmd_mark_cancelable);
118
io_uring_cmd_work(struct io_kiocb * req,struct io_tw_state * ts)119 static void io_uring_cmd_work(struct io_kiocb *req, struct io_tw_state *ts)
120 {
121 struct io_uring_cmd *ioucmd = io_kiocb_to_cmd(req, struct io_uring_cmd);
122 unsigned int flags = IO_URING_F_COMPLETE_DEFER;
123
124 if (current->flags & (PF_EXITING | PF_KTHREAD))
125 flags |= IO_URING_F_TASK_DEAD;
126
127 /* task_work executor checks the deffered list completion */
128 ioucmd->task_work_cb(ioucmd, flags);
129 }
130
__io_uring_cmd_do_in_task(struct io_uring_cmd * ioucmd,void (* task_work_cb)(struct io_uring_cmd *,unsigned),unsigned flags)131 void __io_uring_cmd_do_in_task(struct io_uring_cmd *ioucmd,
132 void (*task_work_cb)(struct io_uring_cmd *, unsigned),
133 unsigned flags)
134 {
135 struct io_kiocb *req = cmd_to_io_kiocb(ioucmd);
136
137 ioucmd->task_work_cb = task_work_cb;
138 req->io_task_work.func = io_uring_cmd_work;
139 __io_req_task_work_add(req, flags);
140 }
141 EXPORT_SYMBOL_GPL(__io_uring_cmd_do_in_task);
142
io_req_set_cqe32_extra(struct io_kiocb * req,u64 extra1,u64 extra2)143 static inline void io_req_set_cqe32_extra(struct io_kiocb *req,
144 u64 extra1, u64 extra2)
145 {
146 req->big_cqe.extra1 = extra1;
147 req->big_cqe.extra2 = extra2;
148 }
149
150 /*
151 * Called by consumers of io_uring_cmd, if they originally returned
152 * -EIOCBQUEUED upon receiving the command.
153 */
io_uring_cmd_done(struct io_uring_cmd * ioucmd,ssize_t ret,u64 res2,unsigned issue_flags)154 void io_uring_cmd_done(struct io_uring_cmd *ioucmd, ssize_t ret, u64 res2,
155 unsigned issue_flags)
156 {
157 struct io_kiocb *req = cmd_to_io_kiocb(ioucmd);
158
159 io_uring_cmd_del_cancelable(ioucmd, issue_flags);
160
161 if (ret < 0)
162 req_set_fail(req);
163
164 io_req_set_res(req, ret, 0);
165 if (req->ctx->flags & IORING_SETUP_CQE32)
166 io_req_set_cqe32_extra(req, res2, 0);
167 io_req_uring_cleanup(req, issue_flags);
168 if (req->ctx->flags & IORING_SETUP_IOPOLL) {
169 /* order with io_iopoll_req_issued() checking ->iopoll_complete */
170 smp_store_release(&req->iopoll_completed, 1);
171 } else if (issue_flags & IO_URING_F_COMPLETE_DEFER) {
172 if (WARN_ON_ONCE(issue_flags & IO_URING_F_UNLOCKED))
173 return;
174 io_req_complete_defer(req);
175 } else {
176 req->io_task_work.func = io_req_task_complete;
177 io_req_task_work_add(req);
178 }
179 }
180 EXPORT_SYMBOL_GPL(io_uring_cmd_done);
181
io_uring_cmd_prep_setup(struct io_kiocb * req,const struct io_uring_sqe * sqe)182 static int io_uring_cmd_prep_setup(struct io_kiocb *req,
183 const struct io_uring_sqe *sqe)
184 {
185 struct io_uring_cmd *ioucmd = io_kiocb_to_cmd(req, struct io_uring_cmd);
186 struct uring_cache *cache;
187
188 cache = io_uring_async_get(req);
189 if (unlikely(!cache))
190 return -ENOMEM;
191
192 if (!(req->flags & REQ_F_FORCE_ASYNC)) {
193 /* defer memcpy until we need it */
194 ioucmd->sqe = sqe;
195 return 0;
196 }
197
198 memcpy(req->async_data, sqe, uring_sqe_size(req->ctx));
199 ioucmd->sqe = req->async_data;
200 return 0;
201 }
202
io_uring_cmd_prep(struct io_kiocb * req,const struct io_uring_sqe * sqe)203 int io_uring_cmd_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
204 {
205 struct io_uring_cmd *ioucmd = io_kiocb_to_cmd(req, struct io_uring_cmd);
206
207 if (sqe->__pad1)
208 return -EINVAL;
209
210 ioucmd->flags = READ_ONCE(sqe->uring_cmd_flags);
211 if (ioucmd->flags & ~IORING_URING_CMD_MASK)
212 return -EINVAL;
213
214 if (ioucmd->flags & IORING_URING_CMD_FIXED) {
215 struct io_ring_ctx *ctx = req->ctx;
216 struct io_rsrc_node *node;
217 u16 index = READ_ONCE(sqe->buf_index);
218
219 node = io_rsrc_node_lookup(&ctx->buf_table, index);
220 if (unlikely(!node))
221 return -EFAULT;
222 /*
223 * Pi node upfront, prior to io_uring_cmd_import_fixed()
224 * being called. This prevents destruction of the mapped buffer
225 * we'll need at actual import time.
226 */
227 io_req_assign_buf_node(req, node);
228 }
229 ioucmd->cmd_op = READ_ONCE(sqe->cmd_op);
230
231 return io_uring_cmd_prep_setup(req, sqe);
232 }
233
io_uring_cmd(struct io_kiocb * req,unsigned int issue_flags)234 int io_uring_cmd(struct io_kiocb *req, unsigned int issue_flags)
235 {
236 struct io_uring_cmd *ioucmd = io_kiocb_to_cmd(req, struct io_uring_cmd);
237 struct io_ring_ctx *ctx = req->ctx;
238 struct file *file = req->file;
239 int ret;
240
241 if (!file->f_op->uring_cmd)
242 return -EOPNOTSUPP;
243
244 ret = security_uring_cmd(ioucmd);
245 if (ret)
246 return ret;
247
248 if (ctx->flags & IORING_SETUP_SQE128)
249 issue_flags |= IO_URING_F_SQE128;
250 if (ctx->flags & IORING_SETUP_CQE32)
251 issue_flags |= IO_URING_F_CQE32;
252 if (ctx->compat)
253 issue_flags |= IO_URING_F_COMPAT;
254 if (ctx->flags & IORING_SETUP_IOPOLL) {
255 if (!file->f_op->uring_cmd_iopoll)
256 return -EOPNOTSUPP;
257 issue_flags |= IO_URING_F_IOPOLL;
258 req->iopoll_completed = 0;
259 }
260
261 ret = file->f_op->uring_cmd(ioucmd, issue_flags);
262 if (ret == -EAGAIN) {
263 struct uring_cache *cache = req->async_data;
264
265 if (ioucmd->sqe != (void *) cache)
266 memcpy(cache, ioucmd->sqe, uring_sqe_size(req->ctx));
267 return -EAGAIN;
268 } else if (ret == -EIOCBQUEUED) {
269 return -EIOCBQUEUED;
270 }
271
272 if (ret < 0)
273 req_set_fail(req);
274 io_req_uring_cleanup(req, issue_flags);
275 io_req_set_res(req, ret, 0);
276 return IOU_OK;
277 }
278
io_uring_cmd_import_fixed(u64 ubuf,unsigned long len,int rw,struct iov_iter * iter,void * ioucmd)279 int io_uring_cmd_import_fixed(u64 ubuf, unsigned long len, int rw,
280 struct iov_iter *iter, void *ioucmd)
281 {
282 struct io_kiocb *req = cmd_to_io_kiocb(ioucmd);
283 struct io_rsrc_node *node = req->buf_node;
284
285 /* Must have had rsrc_node assigned at prep time */
286 if (node)
287 return io_import_fixed(rw, iter, node->buf, ubuf, len);
288
289 return -EFAULT;
290 }
291 EXPORT_SYMBOL_GPL(io_uring_cmd_import_fixed);
292
io_uring_cmd_issue_blocking(struct io_uring_cmd * ioucmd)293 void io_uring_cmd_issue_blocking(struct io_uring_cmd *ioucmd)
294 {
295 struct io_kiocb *req = cmd_to_io_kiocb(ioucmd);
296
297 io_req_queue_iowq(req);
298 }
299
io_uring_cmd_getsockopt(struct socket * sock,struct io_uring_cmd * cmd,unsigned int issue_flags)300 static inline int io_uring_cmd_getsockopt(struct socket *sock,
301 struct io_uring_cmd *cmd,
302 unsigned int issue_flags)
303 {
304 bool compat = !!(issue_flags & IO_URING_F_COMPAT);
305 int optlen, optname, level, err;
306 void __user *optval;
307
308 level = READ_ONCE(cmd->sqe->level);
309 if (level != SOL_SOCKET)
310 return -EOPNOTSUPP;
311
312 optval = u64_to_user_ptr(READ_ONCE(cmd->sqe->optval));
313 optname = READ_ONCE(cmd->sqe->optname);
314 optlen = READ_ONCE(cmd->sqe->optlen);
315
316 err = do_sock_getsockopt(sock, compat, level, optname,
317 USER_SOCKPTR(optval),
318 KERNEL_SOCKPTR(&optlen));
319 if (err)
320 return err;
321
322 /* On success, return optlen */
323 return optlen;
324 }
325
io_uring_cmd_setsockopt(struct socket * sock,struct io_uring_cmd * cmd,unsigned int issue_flags)326 static inline int io_uring_cmd_setsockopt(struct socket *sock,
327 struct io_uring_cmd *cmd,
328 unsigned int issue_flags)
329 {
330 bool compat = !!(issue_flags & IO_URING_F_COMPAT);
331 int optname, optlen, level;
332 void __user *optval;
333 sockptr_t optval_s;
334
335 optval = u64_to_user_ptr(READ_ONCE(cmd->sqe->optval));
336 optname = READ_ONCE(cmd->sqe->optname);
337 optlen = READ_ONCE(cmd->sqe->optlen);
338 level = READ_ONCE(cmd->sqe->level);
339 optval_s = USER_SOCKPTR(optval);
340
341 return do_sock_setsockopt(sock, compat, level, optname, optval_s,
342 optlen);
343 }
344
345 #if defined(CONFIG_NET)
io_uring_cmd_sock(struct io_uring_cmd * cmd,unsigned int issue_flags)346 int io_uring_cmd_sock(struct io_uring_cmd *cmd, unsigned int issue_flags)
347 {
348 struct socket *sock = cmd->file->private_data;
349 struct sock *sk = sock->sk;
350 struct proto *prot = READ_ONCE(sk->sk_prot);
351 int ret, arg = 0;
352
353 if (!prot || !prot->ioctl)
354 return -EOPNOTSUPP;
355
356 switch (cmd->sqe->cmd_op) {
357 case SOCKET_URING_OP_SIOCINQ:
358 ret = prot->ioctl(sk, SIOCINQ, &arg);
359 if (ret)
360 return ret;
361 return arg;
362 case SOCKET_URING_OP_SIOCOUTQ:
363 ret = prot->ioctl(sk, SIOCOUTQ, &arg);
364 if (ret)
365 return ret;
366 return arg;
367 case SOCKET_URING_OP_GETSOCKOPT:
368 return io_uring_cmd_getsockopt(sock, cmd, issue_flags);
369 case SOCKET_URING_OP_SETSOCKOPT:
370 return io_uring_cmd_setsockopt(sock, cmd, issue_flags);
371 default:
372 return -EOPNOTSUPP;
373 }
374 }
375 EXPORT_SYMBOL_GPL(io_uring_cmd_sock);
376 #endif
377