1 /*	$NetBSD: linux_misc_notalpha.c,v 1.115 2022/05/22 11:27:34 andvar Exp $	*/
2 
3 /*-
4  * Copyright (c) 1995, 1998, 2008, 2020 The NetBSD Foundation, Inc.
5  * All rights reserved.
6  *
7  * This code is derived from software contributed to The NetBSD Foundation
8  * by Frank van der Linden and Eric Haszlakiewicz; by Jason R. Thorpe
9  * of the Numerical Aerospace Simulation Facility, NASA Ames Research Center.
10  *
11  * Redistribution and use in source and binary forms, with or without
12  * modification, are permitted provided that the following conditions
13  * are met:
14  * 1. Redistributions of source code must retain the above copyright
15  *    notice, this list of conditions and the following disclaimer.
16  * 2. Redistributions in binary form must reproduce the above copyright
17  *    notice, this list of conditions and the following disclaimer in the
18  *    documentation and/or other materials provided with the distribution.
19  *
20  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
21  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
22  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
23  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
24  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
25  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
26  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
27  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
28  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
29  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
30  * POSSIBILITY OF SUCH DAMAGE.
31  */
32 
33 #include <sys/cdefs.h>
34 __KERNEL_RCSID(0, "$NetBSD: linux_misc_notalpha.c,v 1.115 2022/05/22 11:27:34 andvar Exp $");
35 
36 /*
37  * Note that we must NOT include "opt_compat_linux32.h" here,
38  * the maze of ifdefs below relies on COMPAT_LINUX32 only being
39  * defined when this file is built for linux32.
40  */
41 
42 #include <sys/param.h>
43 #include <sys/systm.h>
44 #include <sys/kernel.h>
45 #include <sys/mman.h>
46 #include <sys/mount.h>
47 #include <sys/mbuf.h>
48 #include <sys/namei.h>
49 #include <sys/proc.h>
50 #include <sys/prot.h>
51 #include <sys/ptrace.h>
52 #include <sys/resource.h>
53 #include <sys/resourcevar.h>
54 #include <sys/time.h>
55 #include <sys/vfs_syscalls.h>
56 #include <sys/wait.h>
57 #include <sys/kauth.h>
58 
59 #include <sys/syscallargs.h>
60 
61 #include <compat/linux/common/linux_types.h>
62 #include <compat/linux/common/linux_fcntl.h>
63 #include <compat/linux/common/linux_misc.h>
64 #include <compat/linux/common/linux_mmap.h>
65 #include <compat/linux/common/linux_signal.h>
66 #include <compat/linux/common/linux_util.h>
67 #include <compat/linux/common/linux_ipc.h>
68 #include <compat/linux/common/linux_sem.h>
69 #include <compat/linux/common/linux_statfs.h>
70 
71 #include <compat/linux/linux_syscallargs.h>
72 
73 /*
74  * This file contains routines which are used
75  * on every linux architecture except the Alpha.
76  */
77 
78 /* Used on: arm, aarch64, i386, m68k, mips, ppc, sparc, sparc64 */
79 /* Not used on: alpha */
80 
81 #ifdef DEBUG_LINUX
82 #define DPRINTF(a)	uprintf a
83 #else
84 #define DPRINTF(a)
85 #endif
86 
87 #ifndef COMPAT_LINUX32
88 /*
89  * Alarm. This is a libc call which uses setitimer(2) in NetBSD.
90  * Do the same here.
91  */
92 int
linux_sys_alarm(struct lwp * l,const struct linux_sys_alarm_args * uap,register_t * retval)93 linux_sys_alarm(struct lwp *l, const struct linux_sys_alarm_args *uap, register_t *retval)
94 {
95 	/* {
96 		syscallarg(unsigned int) secs;
97 	} */
98 	struct proc *p = l->l_proc;
99 	struct itimerval itv, oitv;
100 	int error;
101 
102 	timerclear(&itv.it_interval);
103 	itv.it_value.tv_sec = SCARG(uap, secs);
104 	itv.it_value.tv_usec = 0;
105 	if (itv.it_value.tv_sec < 0) {
106 		return EINVAL;
107 	}
108 
109 	if ((error = dogetitimer(p, ITIMER_REAL, &oitv)) != 0) {
110 		return error;
111 	}
112 	if (oitv.it_value.tv_usec) {
113 		oitv.it_value.tv_sec++;
114 	}
115 
116 	if ((error = dosetitimer(p, ITIMER_REAL, &itv)) != 0) {
117 		return error;
118 	}
119 
120 	*retval = oitv.it_value.tv_sec;
121 	return 0;
122 }
123 #endif /* !COMPAT_LINUX32 */
124 
125 #if !defined(__aarch64__) && !defined(__amd64__)
126 int
linux_sys_nice(struct lwp * l,const struct linux_sys_nice_args * uap,register_t * retval)127 linux_sys_nice(struct lwp *l, const struct linux_sys_nice_args *uap, register_t *retval)
128 {
129 	/* {
130 		syscallarg(int) incr;
131 	} */
132 	struct proc *p = l->l_proc;
133 	struct sys_setpriority_args bsa;
134 	int error;
135 
136 	SCARG(&bsa, which) = PRIO_PROCESS;
137 	SCARG(&bsa, who) = 0;
138 	SCARG(&bsa, prio) = p->p_nice - NZERO + SCARG(uap, incr);
139 
140 	error = sys_setpriority(l, &bsa, retval);
141 	return (error) ? EPERM : 0;
142 }
143 #endif /* !__aarch64__ && !__amd64__ */
144 
145 #ifndef COMPAT_LINUX32
146 #if !defined(__aarch64__) && !defined(__amd64__)
147 /*
148  * The old Linux readdir was only able to read one entry at a time,
149  * even though it had a 'count' argument. In fact, the emulation
150  * of the old call was better than the original, because it did handle
151  * the count arg properly. Don't bother with it anymore now, and use
152  * it to distinguish between old and new. The difference is that the
153  * newer one actually does multiple entries, and the reclen field
154  * really is the reclen, not the namelength.
155  */
156 int
linux_sys_readdir(struct lwp * l,const struct linux_sys_readdir_args * uap,register_t * retval)157 linux_sys_readdir(struct lwp *l, const struct linux_sys_readdir_args *uap, register_t *retval)
158 {
159 	/* {
160 		syscallarg(int) fd;
161 		syscallarg(struct linux_dirent *) dent;
162 		syscallarg(unsigned int) count;
163 	} */
164 	int error;
165 	struct linux_sys_getdents_args da;
166 
167 	SCARG(&da, fd) = SCARG(uap, fd);
168 	SCARG(&da, dent) = SCARG(uap, dent);
169 	SCARG(&da, count) = 1;
170 
171 	error = linux_sys_getdents(l, &da, retval);
172 	if (error == 0 && *retval > 1)
173 		*retval = 1;
174 
175 	return error;
176 }
177 #endif /* !aarch64 && !amd64 */
178 
179 #if !defined(__aarch64__)
180 /*
181  * I wonder why Linux has gettimeofday() _and_ time().. Still, we
182  * need to deal with it.
183  */
184 int
linux_sys_time(struct lwp * l,const struct linux_sys_time_args * uap,register_t * retval)185 linux_sys_time(struct lwp *l, const struct linux_sys_time_args *uap, register_t *retval)
186 {
187 	/* {
188 		syscallarg(linux_time_t) *t;
189 	} */
190 	struct timeval atv;
191 	linux_time_t tt;
192 	int error;
193 
194 	microtime(&atv);
195 
196 	tt = atv.tv_sec;
197 	if (SCARG(uap, t) && (error = copyout(&tt, SCARG(uap, t), sizeof tt)))
198 		return error;
199 
200 	retval[0] = tt;
201 	return 0;
202 }
203 #endif
204 
205 #if !defined(__aarch64__)
206 /*
207  * utime(). Do conversion to things that utimes() understands,
208  * and pass it on.
209  */
210 int
linux_sys_utime(struct lwp * l,const struct linux_sys_utime_args * uap,register_t * retval)211 linux_sys_utime(struct lwp *l, const struct linux_sys_utime_args *uap, register_t *retval)
212 {
213 	/* {
214 		syscallarg(const char *) path;
215 		syscallarg(struct linux_utimbuf *)times;
216 	} */
217 	int error;
218 	struct timeval tv[2], *tvp;
219 	struct linux_utimbuf lut;
220 
221 	if (SCARG(uap, times) != NULL) {
222 		if ((error = copyin(SCARG(uap, times), &lut, sizeof lut)))
223 			return error;
224 		tv[0].tv_usec = tv[1].tv_usec = 0;
225 		tv[0].tv_sec = lut.l_actime;
226 		tv[1].tv_sec = lut.l_modtime;
227 		tvp = tv;
228 	} else
229 		tvp = NULL;
230 
231 	return do_sys_utimes(l, NULL, SCARG(uap, path), FOLLOW,
232 			   tvp,  UIO_SYSSPACE);
233 }
234 #endif
235 
236 #if !defined(__aarch64__) && !defined(__amd64__)
237 /*
238  * waitpid(2).  Just forward on to linux_sys_wait4 with a NULL rusage.
239  */
240 int
linux_sys_waitpid(struct lwp * l,const struct linux_sys_waitpid_args * uap,register_t * retval)241 linux_sys_waitpid(struct lwp *l, const struct linux_sys_waitpid_args *uap, register_t *retval)
242 {
243 	/* {
244 		syscallarg(int) pid;
245 		syscallarg(int *) status;
246 		syscallarg(int) options;
247 	} */
248 	struct linux_sys_wait4_args linux_w4a;
249 
250 	SCARG(&linux_w4a, pid) = SCARG(uap, pid);
251 	SCARG(&linux_w4a, status) = SCARG(uap, status);
252 	SCARG(&linux_w4a, options) = SCARG(uap, options);
253 	SCARG(&linux_w4a, rusage) = NULL;
254 
255 	return linux_sys_wait4(l, &linux_w4a, retval);
256 }
257 #endif /* !aarch64 && !amd64 */
258 
259 int
linux_sys_setresgid(struct lwp * l,const struct linux_sys_setresgid_args * uap,register_t * retval)260 linux_sys_setresgid(struct lwp *l, const struct linux_sys_setresgid_args *uap, register_t *retval)
261 {
262 	/* {
263 		syscallarg(gid_t) rgid;
264 		syscallarg(gid_t) egid;
265 		syscallarg(gid_t) sgid;
266 	} */
267 
268 	/*
269 	 * Note: These checks are a little different than the NetBSD
270 	 * setregid(2) call performs.  This precisely follows the
271 	 * behavior of the Linux kernel.
272 	 */
273 	return do_setresgid(l, SCARG(uap,rgid), SCARG(uap, egid),
274 			    SCARG(uap, sgid),
275 			    ID_R_EQ_R | ID_R_EQ_E | ID_R_EQ_S |
276 			    ID_E_EQ_R | ID_E_EQ_E | ID_E_EQ_S |
277 			    ID_S_EQ_R | ID_S_EQ_E | ID_S_EQ_S );
278 }
279 
280 int
linux_sys_getresgid(struct lwp * l,const struct linux_sys_getresgid_args * uap,register_t * retval)281 linux_sys_getresgid(struct lwp *l, const struct linux_sys_getresgid_args *uap, register_t *retval)
282 {
283 	/* {
284 		syscallarg(gid_t *) rgid;
285 		syscallarg(gid_t *) egid;
286 		syscallarg(gid_t *) sgid;
287 	} */
288 	kauth_cred_t pc = l->l_cred;
289 	int error;
290 	gid_t gid;
291 
292 	/*
293 	 * Linux copies these values out to userspace like so:
294 	 *
295 	 *	1. Copy out rgid.
296 	 *	2. If that succeeds, copy out egid.
297 	 *	3. If both of those succeed, copy out sgid.
298 	 */
299 	gid = kauth_cred_getgid(pc);
300 	if ((error = copyout(&gid, SCARG(uap, rgid), sizeof(gid_t))) != 0)
301 		return (error);
302 
303 	gid = kauth_cred_getegid(pc);
304 	if ((error = copyout(&gid, SCARG(uap, egid), sizeof(gid_t))) != 0)
305 		return (error);
306 
307 	gid = kauth_cred_getsvgid(pc);
308 
309 	return (copyout(&gid, SCARG(uap, sgid), sizeof(gid_t)));
310 }
311 
312 #if !defined(__aarch64__) && !defined(__amd64__)
313 /*
314  * I wonder why Linux has settimeofday() _and_ stime().. Still, we
315  * need to deal with it.
316  */
317 int
linux_sys_stime(struct lwp * l,const struct linux_sys_stime_args * uap,register_t * retval)318 linux_sys_stime(struct lwp *l, const struct linux_sys_stime_args *uap, register_t *retval)
319 {
320 	/* {
321 		syscallarg(linux_time_t) *t;
322 	} */
323 	struct timespec ats;
324 	linux_time_t tt;
325 	int error;
326 
327 	if ((error = copyin(SCARG(uap, t), &tt, sizeof tt)) != 0)
328 		return error;
329 
330 	ats.tv_sec = tt;
331 	ats.tv_nsec = 0;
332 
333 	if ((error = settime(l->l_proc, &ats)))
334 		return (error);
335 
336 	return 0;
337 }
338 
339 /*
340  * Implement the fs stat functions. Straightforward.
341  */
342 int
linux_sys_statfs64(struct lwp * l,const struct linux_sys_statfs64_args * uap,register_t * retval)343 linux_sys_statfs64(struct lwp *l, const struct linux_sys_statfs64_args *uap, register_t *retval)
344 {
345 	/* {
346 		syscallarg(const char *) path;
347 		syscallarg(size_t) sz;
348 		syscallarg(struct linux_statfs64 *) sp;
349 	} */
350 	struct statvfs *sb;
351 	struct linux_statfs64 ltmp;
352 	int error;
353 
354 	if (SCARG(uap, sz) != sizeof ltmp)
355 		return (EINVAL);
356 
357 	sb = STATVFSBUF_GET();
358 	error = do_sys_pstatvfs(l, SCARG(uap, path), ST_WAIT, sb);
359 	if (error == 0) {
360 		bsd_to_linux_statfs64(sb, &ltmp);
361 		error = copyout(&ltmp, SCARG(uap, sp), sizeof ltmp);
362 	}
363 	STATVFSBUF_PUT(sb);
364 	return error;
365 }
366 
367 int
linux_sys_fstatfs64(struct lwp * l,const struct linux_sys_fstatfs64_args * uap,register_t * retval)368 linux_sys_fstatfs64(struct lwp *l, const struct linux_sys_fstatfs64_args *uap, register_t *retval)
369 {
370 	/* {
371 		syscallarg(int) fd;
372 		syscallarg(size_t) sz;
373 		syscallarg(struct linux_statfs64 *) sp;
374 	} */
375 	struct statvfs *sb;
376 	struct linux_statfs64 ltmp;
377 	int error;
378 
379 	if (SCARG(uap, sz) != sizeof ltmp)
380 		return (EINVAL);
381 
382 	sb = STATVFSBUF_GET();
383 	error = do_sys_fstatvfs(l, SCARG(uap, fd), ST_WAIT, sb);
384 	if (error == 0) {
385 		bsd_to_linux_statfs64(sb, &ltmp);
386 		error = copyout(&ltmp, SCARG(uap, sp), sizeof ltmp);
387 	}
388 	STATVFSBUF_PUT(sb);
389 	return error;
390 }
391 #endif /* !aarch64 && !__amd64__ */
392 #endif /* !COMPAT_LINUX32 */
393