2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
4 * Copyright (c) 1994-1996 Søren Schmidt
5 * Copyright (c) 2006 Roman Divacky
6 * Copyright (c) 2013 Dmitry Chagin
9 * Redistribution and use in source and binary forms, with or without
10 * modification, are permitted provided that the following conditions
12 * 1. Redistributions of source code must retain the above copyright
13 * notice, this list of conditions and the following disclaimer.
14 * 2. Redistributions in binary form must reproduce the above copyright
15 * notice, this list of conditions and the following disclaimer in the
16 * documentation and/or other materials provided with the distribution.
18 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
19 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
20 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
21 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
22 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
23 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
24 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
25 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
26 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
27 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31 #include <sys/cdefs.h>
32 __FBSDID("$FreeBSD$");
34 #include <sys/param.h>
35 #include <sys/systm.h>
36 #include <sys/fcntl.h>
37 #include <sys/imgact.h>
38 #include <sys/kernel.h>
41 #include <sys/malloc.h>
42 #include <sys/mutex.h>
45 #include <sys/syscallsubr.h>
46 #include <sys/sysent.h>
48 #include <compat/linux/linux_emul.h>
49 #include <compat/linux/linux_misc.h>
50 #include <compat/linux/linux_persona.h>
51 #include <compat/linux/linux_util.h>
53 #if BYTE_ORDER == LITTLE_ENDIAN
54 #define SHELLMAGIC 0x2123 /* #! */
56 #define SHELLMAGIC 0x2321
60 * This returns reference to the thread emuldata entry (if found)
62 * Hold PROC_LOCK when referencing emuldata from other threads.
64 struct linux_emuldata *
65 em_find(struct thread *td)
67 struct linux_emuldata *em;
75 * This returns reference to the proc pemuldata entry (if found)
77 * Hold PROC_LOCK when referencing proc pemuldata from other threads.
78 * Hold LINUX_PEM_LOCK wher referencing pemuldata members.
80 struct linux_pemuldata *
81 pem_find(struct proc *p)
83 struct linux_pemuldata *pem;
91 linux_proc_init(struct thread *td, struct thread *newtd, int flags)
93 struct linux_emuldata *em;
94 struct linux_pemuldata *pem;
95 struct epoll_emuldata *emd;
102 em = malloc(sizeof(*em), M_TEMP, M_WAITOK | M_ZERO);
103 if (flags & LINUX_CLONE_THREAD) {
104 LINUX_CTR1(proc_init, "thread newtd(%d)",
107 em->em_tid = newtd->td_tid;
109 LINUX_CTR1(proc_init, "fork newtd(%d)", p->p_pid);
111 em->em_tid = p->p_pid;
113 pem = malloc(sizeof(*pem), M_LINUX, M_WAITOK | M_ZERO);
114 sx_init(&pem->pem_sx, "lpemlk");
117 newtd->td_emuldata = em;
122 LINUX_CTR1(proc_init, "exec newtd(%d)", p->p_pid);
124 /* lookup the old one */
126 KASSERT(em != NULL, ("proc_init: emuldata not found in exec case.\n"));
128 em->em_tid = p->p_pid;
130 em->pdeath_signal = 0;
131 em->robust_futexes = NULL;
132 em->child_clear_tid = NULL;
133 em->child_set_tid = NULL;
135 /* epoll should be destroyed in a case of exec. */
137 KASSERT(pem != NULL, ("proc_exit: proc emuldata not found.\n"));
139 if (pem->epoll != NULL) {
149 linux_proc_exit(void *arg __unused, struct proc *p)
151 struct linux_pemuldata *pem;
152 struct epoll_emuldata *emd;
153 struct thread *td = curthread;
155 if (__predict_false(SV_CURPROC_ABI() != SV_ABI_LINUX))
158 LINUX_CTR3(proc_exit, "thread(%d) proc(%d) p %p",
159 td->td_tid, p->p_pid, p);
164 (p->p_sysent->sv_thread_detach)(td);
166 p->p_emuldata = NULL;
168 if (pem->epoll != NULL) {
174 sx_destroy(&pem->pem_sx);
179 * If a Linux binary is exec'ing something, try this image activator
180 * first. We override standard shell script execution in order to
181 * be able to modify the interpreter path. We only do this if a Linux
182 * binary is doing the exec, so we do not create an EXEC module for it.
185 linux_exec_imgact_try(struct image_params *imgp)
187 const char *head = (const char *)imgp->image_header;
192 * The interpreter for shell scripts run from a Linux binary needs
193 * to be located in /compat/linux if possible in order to recursively
194 * maintain Linux path emulation.
196 if (((const short *)head)[0] == SHELLMAGIC) {
198 * Run our normal shell image activator. If it succeeds attempt
199 * to use the alternate path for the interpreter. If an
200 * alternate path is found, use our stringspace to store it.
202 if ((error = exec_shell_imgact(imgp)) == 0) {
203 linux_emul_convpath(FIRST_THREAD_IN_PROC(imgp->proc),
204 imgp->interpreter_name, UIO_SYSSPACE, &rpath, 0,
207 imgp->args->fname_buf =
208 imgp->interpreter_name = rpath;
215 linux_common_execve(struct thread *td, struct image_args *eargs)
217 struct linux_pemuldata *pem;
218 struct epoll_emuldata *emd;
219 struct vmspace *oldvmspace;
220 struct linux_emuldata *em;
226 error = pre_execve(td, &oldvmspace);
230 error = kern_execve(td, eargs, NULL);
231 post_execve(td, error, oldvmspace);
232 if (error != EJUSTRETURN)
236 * In a case of transition from Linux binary execing to
237 * FreeBSD binary we destroy Linux emuldata thread & proc entries.
239 if (SV_CURPROC_ABI() != SV_ABI_LINUX) {
242 KASSERT(em != NULL, ("proc_exec: thread emuldata not found.\n"));
243 td->td_emuldata = NULL;
246 KASSERT(pem != NULL, ("proc_exec: proc pemuldata not found.\n"));
247 p->p_emuldata = NULL;
250 if (pem->epoll != NULL) {
259 return (EJUSTRETURN);
263 linux_proc_exec(void *arg __unused, struct proc *p, struct image_params *imgp)
265 struct thread *td = curthread;
266 struct thread *othertd;
267 #if defined(__amd64__)
268 struct linux_pemuldata *pem;
272 * In a case of execing from Linux binary properly detach
273 * other threads from the user space.
275 if (__predict_false(SV_PROC_ABI(p) == SV_ABI_LINUX)) {
276 FOREACH_THREAD_IN_PROC(p, othertd) {
278 (p->p_sysent->sv_thread_detach)(othertd);
283 * In a case of execing to Linux binary we create Linux
284 * emuldata thread entry.
286 if (__predict_false((imgp->sysent->sv_flags & SV_ABI_MASK) ==
289 if (SV_PROC_ABI(p) == SV_ABI_LINUX)
290 linux_proc_init(td, NULL, 0);
292 linux_proc_init(td, td, 0);
293 #if defined(__amd64__)
295 * An IA32 executable which has executable stack will have the
296 * READ_IMPLIES_EXEC personality flag set automatically.
298 if (SV_PROC_FLAG(td->td_proc, SV_ILP32) &&
299 imgp->stack_prot & VM_PROT_EXECUTE) {
301 pem->persona |= LINUX_READ_IMPLIES_EXEC;
308 linux_thread_dtor(void *arg __unused, struct thread *td)
310 struct linux_emuldata *em;
315 td->td_emuldata = NULL;
317 LINUX_CTR1(thread_dtor, "thread(%d)", em->em_tid);
323 linux_schedtail(struct thread *td)
325 struct linux_emuldata *em;
333 KASSERT(em != NULL, ("linux_schedtail: thread emuldata not found.\n"));
334 child_set_tid = em->child_set_tid;
336 if (child_set_tid != NULL) {
337 error = copyout(&em->em_tid, child_set_tid,
339 LINUX_CTR4(schedtail, "thread(%d) %p stored %d error %d",
340 td->td_tid, child_set_tid, em->em_tid, error);
342 LINUX_CTR1(schedtail, "thread(%d)", em->em_tid);