xref: /optee_os/core/kernel/ldelf_loader.c (revision 74f6dd9bbb68b3dc3d475da445d84cccafd4d94d)
1 // SPDX-License-Identifier: BSD-2-Clause
2 /*
3  * Copyright (c) 2014, STMicroelectronics International N.V.
4  * Copyright (c) 2015-2020, 2022 Linaro Limited
5  * Copyright (c) 2020-2021, Arm Limited
6  */
7 
8 #include <assert.h>
9 #include <kernel/ldelf_loader.h>
10 #include <kernel/ldelf_syscalls.h>
11 #include <kernel/scall.h>
12 #include <ldelf.h>
13 #include <mm/mobj.h>
14 #include <mm/vm.h>
15 
16 extern uint8_t ldelf_data[];
17 extern const unsigned int ldelf_code_size;
18 extern const unsigned int ldelf_data_size;
19 extern const unsigned int ldelf_entry;
20 
21 /* ldelf has the same architecture/register width as the kernel */
22 #if defined(ARM32) || defined(RV32)
23 static const bool is_32bit = true;
24 #else
25 static const bool is_32bit;
26 #endif
27 
28 static TEE_Result alloc_and_map_ldelf_fobj(struct user_mode_ctx *uctx,
29 					   size_t sz, uint32_t prot,
30 					   vaddr_t *va)
31 {
32 	size_t num_pgs = ROUNDUP(sz, SMALL_PAGE_SIZE) / SMALL_PAGE_SIZE;
33 	struct fobj *fobj = fobj_ta_mem_alloc(num_pgs);
34 	struct mobj *mobj = mobj_with_fobj_alloc(fobj, NULL,
35 						 TEE_MATTR_MEM_TYPE_TAGGED);
36 	TEE_Result res = TEE_SUCCESS;
37 
38 	fobj_put(fobj);
39 	if (!mobj)
40 		return TEE_ERROR_OUT_OF_MEMORY;
41 	res = vm_map(uctx, va, num_pgs * SMALL_PAGE_SIZE,
42 		     prot, VM_FLAG_LDELF, mobj, 0);
43 	mobj_put(mobj);
44 
45 	return res;
46 }
47 
48 /*
49  * This function may leave a few mappings behind on error, but that's taken
50  * care of by tee_ta_init_user_ta_session() since the entire context is
51  * removed then.
52  */
53 TEE_Result ldelf_load_ldelf(struct user_mode_ctx *uctx)
54 {
55 	TEE_Result res = TEE_SUCCESS;
56 	vaddr_t stack_addr = 0;
57 	vaddr_t code_addr = 0;
58 	vaddr_t rw_addr = 0;
59 	uint32_t prot = 0;
60 
61 	uctx->is_32bit = is_32bit;
62 
63 	res = alloc_and_map_ldelf_fobj(uctx, LDELF_STACK_SIZE,
64 				       TEE_MATTR_URW | TEE_MATTR_PRW,
65 				       &stack_addr);
66 	if (res)
67 		return res;
68 	uctx->ldelf_stack_ptr = stack_addr + LDELF_STACK_SIZE;
69 
70 	res = alloc_and_map_ldelf_fobj(uctx, ldelf_code_size, TEE_MATTR_PRW,
71 				       &code_addr);
72 	if (res)
73 		return res;
74 	uctx->entry_func = code_addr + ldelf_entry;
75 
76 	rw_addr = ROUNDUP(code_addr + ldelf_code_size, SMALL_PAGE_SIZE);
77 	res = alloc_and_map_ldelf_fobj(uctx, ldelf_data_size,
78 				       TEE_MATTR_URW | TEE_MATTR_PRW, &rw_addr);
79 	if (res)
80 		return res;
81 
82 	vm_set_ctx(uctx->ts_ctx);
83 
84 	memcpy((void *)code_addr, ldelf_data, ldelf_code_size);
85 	memcpy((void *)rw_addr, ldelf_data + ldelf_code_size, ldelf_data_size);
86 
87 	prot = TEE_MATTR_URX;
88 	if (IS_ENABLED(CFG_CORE_BTI))
89 		prot |= TEE_MATTR_GUARDED;
90 
91 	res = vm_set_prot(uctx, code_addr,
92 			  ROUNDUP(ldelf_code_size, SMALL_PAGE_SIZE), prot);
93 	if (res)
94 		return res;
95 
96 	DMSG("ldelf load address %#"PRIxVA, code_addr);
97 
98 	return TEE_SUCCESS;
99 }
100 
101 TEE_Result ldelf_init_with_ldelf(struct ts_session *sess,
102 				 struct user_mode_ctx *uctx)
103 {
104 	TEE_Result res = TEE_SUCCESS;
105 	struct ldelf_arg *arg = NULL;
106 	uint32_t panic_code = 0;
107 	uint32_t panicked = 0;
108 	uaddr_t usr_stack = 0;
109 
110 	usr_stack = uctx->ldelf_stack_ptr;
111 	usr_stack -= ROUNDUP(sizeof(*arg), STACK_ALIGNMENT);
112 	arg = (struct ldelf_arg *)usr_stack;
113 	memset(arg, 0, sizeof(*arg));
114 	arg->uuid = uctx->ts_ctx->uuid;
115 	sess->handle_scall = scall_handle_ldelf;
116 
117 	res = thread_enter_user_mode((vaddr_t)arg, 0, 0, 0,
118 				     usr_stack, uctx->entry_func,
119 				     is_32bit, &panicked, &panic_code);
120 
121 	sess->handle_scall = sess->ctx->ops->handle_scall;
122 	thread_user_clear_vfp(uctx);
123 	ldelf_sess_cleanup(sess);
124 
125 	if (panicked) {
126 		abort_print_current_ts();
127 		EMSG("ldelf panicked");
128 		return TEE_ERROR_GENERIC;
129 	}
130 	if (res) {
131 		EMSG("ldelf failed with res: %#"PRIx32, res);
132 		return res;
133 	}
134 
135 	res = vm_check_access_rights(uctx,
136 				     TEE_MEMORY_ACCESS_READ |
137 				     TEE_MEMORY_ACCESS_ANY_OWNER,
138 				     (uaddr_t)arg, sizeof(*arg));
139 	if (res)
140 		return res;
141 
142 	if (is_user_ta_ctx(uctx->ts_ctx)) {
143 		/*
144 		 * This is already checked by the elf loader, but since it runs
145 		 * in user mode we're not trusting it entirely.
146 		 */
147 		if (arg->flags & ~TA_FLAGS_MASK)
148 			return TEE_ERROR_BAD_FORMAT;
149 
150 		to_user_ta_ctx(uctx->ts_ctx)->ta_ctx.flags = arg->flags;
151 	}
152 
153 	uctx->is_32bit = arg->is_32bit;
154 	uctx->entry_func = arg->entry_func;
155 	uctx->stack_ptr = arg->stack_ptr;
156 	uctx->dump_entry_func = arg->dump_entry;
157 #ifdef CFG_FTRACE_SUPPORT
158 	uctx->ftrace_entry_func = arg->ftrace_entry;
159 	sess->fbuf = arg->fbuf;
160 #endif
161 	uctx->dl_entry_func = arg->dl_entry;
162 
163 	return TEE_SUCCESS;
164 }
165 
166 TEE_Result ldelf_dump_state(struct user_mode_ctx *uctx)
167 {
168 	TEE_Result res = TEE_SUCCESS;
169 	uaddr_t usr_stack = uctx->ldelf_stack_ptr;
170 	struct dump_entry_arg *arg = NULL;
171 	uint32_t panic_code = 0;
172 	uint32_t panicked = 0;
173 	struct thread_specific_data *tsd = thread_get_tsd();
174 	struct ts_session *sess = NULL;
175 	struct vm_region *r = NULL;
176 	size_t n = 0;
177 
178 	TAILQ_FOREACH(r, &uctx->vm_info.regions, link)
179 		if (r->attr & TEE_MATTR_URWX)
180 			n++;
181 
182 	usr_stack = uctx->ldelf_stack_ptr;
183 	usr_stack -= ROUNDUP(sizeof(*arg) + n * sizeof(struct dump_map),
184 			     STACK_ALIGNMENT);
185 	arg = (struct dump_entry_arg *)usr_stack;
186 
187 	res = vm_check_access_rights(uctx,
188 				     TEE_MEMORY_ACCESS_READ |
189 				     TEE_MEMORY_ACCESS_ANY_OWNER,
190 				     (uaddr_t)arg, sizeof(*arg));
191 	if (res) {
192 		EMSG("ldelf stack is inaccessible!");
193 		return res;
194 	}
195 
196 	memset(arg, 0, sizeof(*arg) + n * sizeof(struct dump_map));
197 
198 	arg->num_maps = n;
199 	n = 0;
200 	TAILQ_FOREACH(r, &uctx->vm_info.regions, link) {
201 		if (r->attr & TEE_MATTR_URWX) {
202 			if (r->mobj)
203 				mobj_get_pa(r->mobj, r->offset, 0,
204 					    &arg->maps[n].pa);
205 			arg->maps[n].va = r->va;
206 			arg->maps[n].sz = r->size;
207 			if (r->attr & TEE_MATTR_UR)
208 				arg->maps[n].flags |= DUMP_MAP_READ;
209 			if (r->attr & TEE_MATTR_UW)
210 				arg->maps[n].flags |= DUMP_MAP_WRITE;
211 			if (r->attr & TEE_MATTR_UX)
212 				arg->maps[n].flags |= DUMP_MAP_EXEC;
213 			if (r->attr & TEE_MATTR_SECURE)
214 				arg->maps[n].flags |= DUMP_MAP_SECURE;
215 			if (r->flags & VM_FLAG_EPHEMERAL)
216 				arg->maps[n].flags |= DUMP_MAP_EPHEM;
217 			if (r->flags & VM_FLAG_LDELF)
218 				arg->maps[n].flags |= DUMP_MAP_LDELF;
219 			n++;
220 		}
221 	}
222 
223 	arg->is_32bit = uctx->is_32bit;
224 #ifdef ARM32
225 	arg->arm32.regs[0] = tsd->abort_regs.r0;
226 	arg->arm32.regs[1] = tsd->abort_regs.r1;
227 	arg->arm32.regs[2] = tsd->abort_regs.r2;
228 	arg->arm32.regs[3] = tsd->abort_regs.r3;
229 	arg->arm32.regs[4] = tsd->abort_regs.r4;
230 	arg->arm32.regs[5] = tsd->abort_regs.r5;
231 	arg->arm32.regs[6] = tsd->abort_regs.r6;
232 	arg->arm32.regs[7] = tsd->abort_regs.r7;
233 	arg->arm32.regs[8] = tsd->abort_regs.r8;
234 	arg->arm32.regs[9] = tsd->abort_regs.r9;
235 	arg->arm32.regs[10] = tsd->abort_regs.r10;
236 	arg->arm32.regs[11] = tsd->abort_regs.r11;
237 	arg->arm32.regs[12] = tsd->abort_regs.ip;
238 	arg->arm32.regs[13] = tsd->abort_regs.usr_sp; /*SP*/
239 	arg->arm32.regs[14] = tsd->abort_regs.usr_lr; /*LR*/
240 	arg->arm32.regs[15] = tsd->abort_regs.elr; /*PC*/
241 #endif /*ARM32*/
242 #ifdef ARM64
243 	if (uctx->is_32bit) {
244 		arg->arm32.regs[0] = tsd->abort_regs.x0;
245 		arg->arm32.regs[1] = tsd->abort_regs.x1;
246 		arg->arm32.regs[2] = tsd->abort_regs.x2;
247 		arg->arm32.regs[3] = tsd->abort_regs.x3;
248 		arg->arm32.regs[4] = tsd->abort_regs.x4;
249 		arg->arm32.regs[5] = tsd->abort_regs.x5;
250 		arg->arm32.regs[6] = tsd->abort_regs.x6;
251 		arg->arm32.regs[7] = tsd->abort_regs.x7;
252 		arg->arm32.regs[8] = tsd->abort_regs.x8;
253 		arg->arm32.regs[9] = tsd->abort_regs.x9;
254 		arg->arm32.regs[10] = tsd->abort_regs.x10;
255 		arg->arm32.regs[11] = tsd->abort_regs.x11;
256 		arg->arm32.regs[12] = tsd->abort_regs.x12;
257 		arg->arm32.regs[13] = tsd->abort_regs.x13; /*SP*/
258 		arg->arm32.regs[14] = tsd->abort_regs.x14; /*LR*/
259 		arg->arm32.regs[15] = tsd->abort_regs.elr; /*PC*/
260 	} else {
261 		arg->arm64.fp = tsd->abort_regs.x29;
262 		arg->arm64.pc = tsd->abort_regs.elr;
263 		arg->arm64.sp = tsd->abort_regs.sp_el0;
264 	}
265 #endif /*ARM64*/
266 #if defined(RV64) || defined(RV32)
267 	arg->rv.fp = tsd->abort_regs.s0;
268 	arg->rv.pc = tsd->abort_regs.epc;
269 	arg->rv.sp = tsd->abort_regs.sp;
270 #endif /*RV64||RV32*/
271 
272 	sess = ts_get_current_session();
273 	sess->handle_scall = scall_handle_ldelf;
274 
275 	res = thread_enter_user_mode((vaddr_t)arg, 0, 0, 0,
276 				     usr_stack, uctx->dump_entry_func,
277 				     is_32bit, &panicked, &panic_code);
278 
279 	sess->handle_scall = sess->ctx->ops->handle_scall;
280 	thread_user_clear_vfp(uctx);
281 	ldelf_sess_cleanup(sess);
282 
283 	if (panicked) {
284 		uctx->dump_entry_func = 0;
285 		EMSG("ldelf dump function panicked");
286 		abort_print_current_ts();
287 		res = TEE_ERROR_TARGET_DEAD;
288 	}
289 
290 	return res;
291 }
292 
293 #ifdef CFG_FTRACE_SUPPORT
294 TEE_Result ldelf_dump_ftrace(struct user_mode_ctx *uctx,
295 			     void *buf, size_t *blen)
296 {
297 	uaddr_t usr_stack = uctx->ldelf_stack_ptr;
298 	TEE_Result res = TEE_SUCCESS;
299 	uint32_t panic_code = 0;
300 	uint32_t panicked = 0;
301 	size_t *arg = NULL;
302 	struct ts_session *sess = NULL;
303 
304 	if (!uctx->ftrace_entry_func)
305 		return TEE_ERROR_NOT_SUPPORTED;
306 
307 	usr_stack -= ROUNDUP(sizeof(*arg), STACK_ALIGNMENT);
308 	arg = (size_t *)usr_stack;
309 
310 	res = vm_check_access_rights(uctx,
311 				     TEE_MEMORY_ACCESS_READ |
312 				     TEE_MEMORY_ACCESS_ANY_OWNER,
313 				     (uaddr_t)arg, sizeof(*arg));
314 	if (res) {
315 		EMSG("ldelf stack is inaccessible!");
316 		return res;
317 	}
318 
319 	*arg = *blen;
320 
321 	sess = ts_get_current_session();
322 	sess->handle_scall = scall_handle_ldelf;
323 
324 	res = thread_enter_user_mode((vaddr_t)buf, (vaddr_t)arg, 0, 0,
325 				     usr_stack, uctx->ftrace_entry_func,
326 				     is_32bit, &panicked, &panic_code);
327 
328 	sess->handle_scall = sess->ctx->ops->handle_scall;
329 	thread_user_clear_vfp(uctx);
330 	ldelf_sess_cleanup(sess);
331 
332 	if (panicked) {
333 		uctx->ftrace_entry_func = 0;
334 		EMSG("ldelf ftrace function panicked");
335 		abort_print_current_ts();
336 		res = TEE_ERROR_TARGET_DEAD;
337 	}
338 
339 	if (!res) {
340 		if (*arg > *blen)
341 			res = TEE_ERROR_SHORT_BUFFER;
342 		*blen = *arg;
343 	}
344 
345 	return res;
346 }
347 #endif /*CFG_FTRACE_SUPPORT*/
348 
349 TEE_Result ldelf_dlopen(struct user_mode_ctx *uctx, TEE_UUID *uuid,
350 			uint32_t flags)
351 {
352 	uaddr_t usr_stack = uctx->ldelf_stack_ptr;
353 	TEE_Result res = TEE_ERROR_GENERIC;
354 	struct dl_entry_arg *arg = NULL;
355 	uint32_t panic_code = 0;
356 	uint32_t panicked = 0;
357 	struct ts_session *sess = NULL;
358 
359 	assert(uuid);
360 
361 	usr_stack -= ROUNDUP(sizeof(*arg), STACK_ALIGNMENT);
362 	arg = (struct dl_entry_arg *)usr_stack;
363 
364 	res = vm_check_access_rights(uctx,
365 				     TEE_MEMORY_ACCESS_READ |
366 				     TEE_MEMORY_ACCESS_WRITE |
367 				     TEE_MEMORY_ACCESS_ANY_OWNER,
368 				     (uaddr_t)arg, sizeof(*arg));
369 	if (res) {
370 		EMSG("ldelf stack is inaccessible!");
371 		return res;
372 	}
373 
374 	memset(arg, 0, sizeof(*arg));
375 	arg->cmd = LDELF_DL_ENTRY_DLOPEN;
376 	arg->dlopen.uuid = *uuid;
377 	arg->dlopen.flags = flags;
378 
379 	sess = ts_get_current_session();
380 	sess->handle_scall = scall_handle_ldelf;
381 
382 	res = thread_enter_user_mode((vaddr_t)arg, 0, 0, 0,
383 				     usr_stack, uctx->dl_entry_func,
384 				     is_32bit, &panicked, &panic_code);
385 
386 	sess->handle_scall = sess->ctx->ops->handle_scall;
387 	ldelf_sess_cleanup(sess);
388 
389 	if (panicked) {
390 		EMSG("ldelf dl_entry function panicked");
391 		abort_print_current_ts();
392 		res = TEE_ERROR_TARGET_DEAD;
393 	}
394 	if (!res)
395 		res = arg->ret;
396 
397 	return res;
398 }
399 
400 TEE_Result ldelf_dlsym(struct user_mode_ctx *uctx, TEE_UUID *uuid,
401 		       const char *sym, size_t maxlen, vaddr_t *val)
402 {
403 	uaddr_t usr_stack = uctx->ldelf_stack_ptr;
404 	TEE_Result res = TEE_ERROR_GENERIC;
405 	struct dl_entry_arg *arg = NULL;
406 	uint32_t panic_code = 0;
407 	uint32_t panicked = 0;
408 	size_t len = strnlen(sym, maxlen);
409 	struct ts_session *sess = NULL;
410 
411 	if (len == maxlen)
412 		return TEE_ERROR_BAD_PARAMETERS;
413 
414 	usr_stack -= ROUNDUP(sizeof(*arg) + len + 1, STACK_ALIGNMENT);
415 	arg = (struct dl_entry_arg *)usr_stack;
416 
417 	res = vm_check_access_rights(uctx,
418 				     TEE_MEMORY_ACCESS_READ |
419 				     TEE_MEMORY_ACCESS_WRITE |
420 				     TEE_MEMORY_ACCESS_ANY_OWNER,
421 				     (uaddr_t)arg, sizeof(*arg) + len + 1);
422 	if (res) {
423 		EMSG("ldelf stack is inaccessible!");
424 		return res;
425 	}
426 
427 	memset(arg, 0, sizeof(*arg));
428 	arg->cmd = LDELF_DL_ENTRY_DLSYM;
429 	arg->dlsym.uuid = *uuid;
430 	memcpy(arg->dlsym.symbol, sym, len);
431 	arg->dlsym.symbol[len] = '\0';
432 
433 	sess = ts_get_current_session();
434 	sess->handle_scall = scall_handle_ldelf;
435 
436 	res = thread_enter_user_mode((vaddr_t)arg, 0, 0, 0,
437 				     usr_stack, uctx->dl_entry_func,
438 				     is_32bit, &panicked, &panic_code);
439 
440 	sess->handle_scall = sess->ctx->ops->handle_scall;
441 	ldelf_sess_cleanup(sess);
442 
443 	if (panicked) {
444 		EMSG("ldelf dl_entry function panicked");
445 		abort_print_current_ts();
446 		res = TEE_ERROR_TARGET_DEAD;
447 	}
448 	if (!res) {
449 		res = arg->ret;
450 		if (!res)
451 			*val = arg->dlsym.val;
452 	}
453 
454 	return res;
455 }
456