Bug Summary

File:src/usr.bin/calendar/io.c
Warning:line 345, column 3
This function call is prohibited after a successful vfork

Annotated Source Code

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clang -cc1 -cc1 -triple amd64-unknown-openbsd7.0 -analyze -disable-free -disable-llvm-verifier -discard-value-names -main-file-name io.c -analyzer-store=region -analyzer-opt-analyze-nested-blocks -analyzer-checker=core -analyzer-checker=apiModeling -analyzer-checker=unix -analyzer-checker=deadcode -analyzer-checker=security.insecureAPI.UncheckedReturn -analyzer-checker=security.insecureAPI.getpw -analyzer-checker=security.insecureAPI.gets -analyzer-checker=security.insecureAPI.mktemp -analyzer-checker=security.insecureAPI.mkstemp -analyzer-checker=security.insecureAPI.vfork -analyzer-checker=nullability.NullPassedToNonnull -analyzer-checker=nullability.NullReturnedFromNonnull -analyzer-output plist -w -setup-static-analyzer -mrelocation-model pic -pic-level 1 -pic-is-pie -mframe-pointer=all -relaxed-aliasing -fno-rounding-math -mconstructor-aliases -munwind-tables -target-cpu x86-64 -target-feature +retpoline-indirect-calls -target-feature +retpoline-indirect-branches -tune-cpu generic -debugger-tuning=gdb -fcoverage-compilation-dir=/usr/src/usr.bin/calendar/obj -resource-dir /usr/local/lib/clang/13.0.0 -internal-isystem /usr/local/lib/clang/13.0.0/include -internal-externc-isystem /usr/include -O2 -fdebug-compilation-dir=/usr/src/usr.bin/calendar/obj -ferror-limit 19 -fwrapv -D_RET_PROTECTOR -ret-protector -fgnuc-version=4.2.1 -vectorize-loops -vectorize-slp -fno-builtin-malloc -fno-builtin-calloc -fno-builtin-realloc -fno-builtin-valloc -fno-builtin-free -fno-builtin-strdup -fno-builtin-strndup -analyzer-output=html -faddrsig -D__GCC_HAVE_DWARF2_CFI_ASM=1 -o /home/ben/Projects/vmm/scan-build/2022-01-12-194120-40624-1 -x c /usr/src/usr.bin/calendar/io.c
1/* $OpenBSD: io.c,v 1.51 2021/12/07 14:00:33 robert Exp $ */
2
3/*
4 * Copyright (c) 1989, 1993, 1994
5 * The Regents of the University of California. All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
15 * 3. Neither the name of the University nor the names of its contributors
16 * may be used to endorse or promote products derived from this software
17 * without specific prior written permission.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29 * SUCH DAMAGE.
30 */
31
32#include <sys/stat.h>
33#include <sys/time.h>
34#include <sys/types.h>
35#include <sys/uio.h>
36#include <sys/wait.h>
37
38#include <ctype.h>
39#include <err.h>
40#include <errno(*__errno()).h>
41#include <fcntl.h>
42#include <locale.h>
43#include <pwd.h>
44#include <stdio.h>
45#include <stdlib.h>
46#include <string.h>
47#include <unistd.h>
48#include <limits.h>
49
50#include "pathnames.h"
51#include "calendar.h"
52
53
54struct iovec header[] = {
55 { "From: ", 6 },
56 { NULL((void *)0), 0 },
57 { " (Reminder Service)\nTo: ", 24 },
58 { NULL((void *)0), 0 },
59 { "\nSubject: ", 10 },
60 { NULL((void *)0), 0 },
61 { "'s Calendar\nPrecedence: bulk\n", 29 },
62 { "Auto-Submitted: auto-generated\n\n", 32 },
63};
64
65
66void
67cal(void)
68{
69 int ch, l, i, bodun = 0, bodun_maybe = 0, var, printing;
70 struct event *events, *cur_evt, *ev1, *tmp;
71 char buf[2048 + 1], *prefix = NULL((void *)0), *p;
72 struct match *m;
73 FILE *fp;
74
75 events = NULL((void *)0);
76 cur_evt = NULL((void *)0);
77 if ((fp = opencal()) == NULL((void *)0))
1
Calling 'opencal'
→
78 return;
79 for (printing = 0; fgets(buf, sizeof(buf), stdin(&__sF[0])) != NULL((void *)0);) {
80 if ((p = strchr(buf, '\n')) != NULL((void *)0))
81 *p = '\0';
82 else
83 while ((ch = getchar()(!__isthreaded ? (--((&__sF[0]))->_r < 0 ? __srget(
(&__sF[0])) : (int)(*((&__sF[0]))->_p++)) : (getc)
((&__sF[0])))) != '\n' && ch != EOF(-1));
84 for (l = strlen(buf); l > 0 && isspace(buf[l - 1]); l--)
85 ;
86 buf[l] = '\0';
87 if (buf[0] == '\0')
88 continue;
89 if (strncmp(buf, "LANG=", 5) == 0) {
90 (void) setlocale(LC_ALL0, buf + 5);
91 setnnames();
92 if (!strcmp(buf + 5, "ru_RU.UTF-8") ||
93 !strcmp(buf + 5, "uk_UA.UTF-8") ||
94 !strcmp(buf + 5, "by_BY.UTF-8")) {
95 bodun_maybe++;
96 bodun = 0;
97 free(prefix);
98 prefix = NULL((void *)0);
99 } else
100 bodun_maybe = 0;
101 continue;
102 } else if (strncmp(buf, "CALENDAR=", 9) == 0) {
103 char *ep;
104
105 if (buf[9] == '\0')
106 calendar = 0;
107 else if (!strcasecmp(buf + 9, "julian")) {
108 calendar = JULIAN;
109 errno(*__errno()) = 0;
110 julian = strtoul(buf + 14, &ep, 10);
111 if (buf[0] == '\0' || *ep != '\0')
112 julian = 13;
113 if ((errno(*__errno()) == ERANGE34 && julian == ULONG_MAX(9223372036854775807L *2UL+1UL)) ||
114 julian > 14)
115 errx(1, "Julian calendar offset is too large");
116 } else if (!strcasecmp(buf + 9, "gregorian"))
117 calendar = GREGORIAN;
118 else if (!strcasecmp(buf + 9, "lunar"))
119 calendar = LUNAR;
120 } else if (bodun_maybe && strncmp(buf, "BODUN=", 6) == 0) {
121 bodun++;
122 free(prefix);
123 if ((prefix = strdup(buf + 6)) == NULL((void *)0))
124 err(1, NULL((void *)0));
125 continue;
126 }
127 /* User defined names for special events */
128 if ((p = strchr(buf, '='))) {
129 for (i = 0; i < NUMEV3; i++) {
130 if (strncasecmp(buf, spev[i].name,
131 spev[i].nlen) == 0 &&
132 (p - buf == spev[i].nlen) &&
133 buf[spev[i].nlen + 1]) {
134 p++;
135 free(spev[i].uname);
136 if ((spev[i].uname = strdup(p)) == NULL((void *)0))
137 err(1, NULL((void *)0));
138 spev[i].ulen = strlen(p);
139 i = NUMEV3 + 1;
140 }
141 }
142 if (i > NUMEV3)
143 continue;
144 }
145 if (buf[0] != '\t') {
146 printing = (m = isnow(buf, bodun)) ? 1 : 0;
147 if ((p = strchr(buf, '\t')) == NULL((void *)0)) {
148 printing = 0;
149 continue;
150 }
151 /* Need the following to catch hardwired "variable"
152 * dates */
153 if (p > buf && p[-1] == '*')
154 var = 1;
155 else
156 var = 0;
157 if (printing) {
158 struct match *foo;
159
160 ev1 = NULL((void *)0);
161 while (m) {
162 cur_evt = malloc(sizeof(struct event));
163 if (cur_evt == NULL((void *)0))
164 err(1, NULL((void *)0));
165
166 cur_evt->when = m->when;
167 snprintf(cur_evt->print_date,
168 sizeof(cur_evt->print_date), "%s%c",
169 m->print_date, (var + m->var) ? '*' : ' ');
170 if (ev1) {
171 cur_evt->desc = ev1->desc;
172 cur_evt->ldesc = NULL((void *)0);
173 } else {
174 if (m->bodun && prefix) {
175 if (asprintf(&cur_evt->ldesc,
176 "\t%s %s", prefix,
177 p + 1) == -1)
178 err(1, NULL((void *)0));
179 } else if ((cur_evt->ldesc =
180 strdup(p)) == NULL((void *)0))
181 err(1, NULL((void *)0));
182 cur_evt->desc = &(cur_evt->ldesc);
183 ev1 = cur_evt;
184 }
185 insert(&events, cur_evt);
186 foo = m;
187 m = m->next;
188 free(foo);
189 }
190 }
191 } else if (printing) {
192 if (asprintf(&p, "%s\n%s", ev1->ldesc,
193 buf) == -1)
194 err(1, NULL((void *)0));
195 free(ev1->ldesc);
196 ev1->ldesc = p;
197 }
198 }
199 tmp = events;
200 while (tmp) {
201 (void)fprintf(fp, "%s%s\n", tmp->print_date, *(tmp->desc));
202 tmp = tmp->next;
203 }
204 tmp = events;
205 while (tmp) {
206 events = tmp;
207 free(tmp->ldesc);
208 tmp = tmp->next;
209 free(events);
210 }
211 closecal(fp);
212}
213
214int
215getfield(char *p, char **endp, int *flags)
216{
217 int val, var, i;
218 char *start, savech;
219
220 for (; !isdigit((unsigned char)*p) && !isalpha((unsigned char)*p) &&
221 *p != '*' && *p != '\t'; ++p)
222 ;
223 if (*p == '*') { /* `*' is every month */
224 *flags |= F_ISMONTH0x01;
225 *endp = p+1;
226 return (-1); /* means 'every month' */
227 }
228 if (isdigit((unsigned char)*p)) {
229 val = strtol(p, &p, 10); /* if 0, it's failure */
230 for (; !isdigit((unsigned char)*p) &&
231 !isalpha((unsigned char)*p) && *p != '*'; ++p)
232 ;
233 *endp = p;
234 return (val);
235 }
236 for (start = p; isalpha((unsigned char)*++p);)
237 ;
238
239 /* Sunday-1 */
240 if (*p == '+' || *p == '-')
241 for(; isdigit((unsigned char)*++p); )
242 ;
243
244 savech = *p;
245 *p = '\0';
246
247 /* Month */
248 if ((val = getmonth(start)) != 0)
249 *flags |= F_ISMONTH0x01;
250
251 /* Day */
252 else if ((val = getday(start)) != 0) {
253 *flags |= F_ISDAY0x02;
254
255 /* variable weekday */
256 if ((var = getdayvar(start)) != 0) {
257 if (var <= 5 && var >= -4)
258 val += var * 10;
259#ifdef DEBUG
260 printf("var: %d\n", var);
261#endif
262 }
263 }
264
265 /* Try specials (Easter, Paskha, ...) */
266 else {
267 for (i = 0; i < NUMEV3; i++) {
268 if (strncasecmp(start, spev[i].name, spev[i].nlen) == 0) {
269 start += spev[i].nlen;
270 val = i + 1;
271 i = NUMEV3 + 1;
272 } else if (spev[i].uname != NULL((void *)0) &&
273 strncasecmp(start, spev[i].uname, spev[i].ulen) == 0) {
274 start += spev[i].ulen;
275 val = i + 1;
276 i = NUMEV3 + 1;
277 }
278 }
279 if (i > NUMEV3) {
280 const char *errstr;
281
282 switch (*start) {
283 case '-':
284 case '+':
285 var = strtonum(start + 1, 0, 365, &errstr);
286 if (errstr)
287 return (0); /* Someone is just being silly */
288 if (*start == '-')
289 var = -var;
290 val += (NUMEV3 + 1) * var;
291 /* We add one to the matching event and multiply by
292 * (NUMEV + 1) so as not to return 0 if there's a match.
293 * val will overflow if there is an obscenely large
294 * number of special events. */
295 break;
296 }
297 *flags |= F_SPECIAL0x08;
298 }
299 if (!(*flags & F_SPECIAL0x08)) {
300 /* undefined rest */
301 *p = savech;
302 return (0);
303 }
304 }
305 for (*p = savech; !isdigit((unsigned char)*p) &&
306 !isalpha((unsigned char)*p) && *p != '*' && *p != '\t'; ++p)
307 ;
308 *endp = p;
309 return (val);
310}
311
312
313FILE *
314opencal(void)
315{
316 int pdes[2], fdin;
317 struct stat st;
318
319 /* open up calendar file as stdin */
320 if ((fdin = open(calendarFile, O_RDONLY0x0000)) == -1 ||
2
←
Assuming the condition is true
→
321 fstat(fdin, &st) == -1 || !S_ISREG(st.st_mode)((st.st_mode & 0170000) == 0100000)) {
322 if (!doall) {
3
←
Assuming 'doall' is not equal to 0
→
4
←
Taking false branch
→
323 char *home = getenv("HOME");
324 if (home == NULL((void *)0) || *home == '\0')
325 errx(1, "cannot get home directory");
326 if (!(chdir(home) == 0 &&
327 chdir(calendarHome) == 0 &&
328 (fdin = open(calendarFile, O_RDONLY0x0000)) != -1))
329 errx(1, "no calendar file: \"%s\" or \"~/%s/%s\"",
330 calendarFile, calendarHome, calendarFile);
331 }
332 }
333
334 if (pipe(pdes) == -1) {
5
←
Assuming the condition is false
→
6
←
Taking false branch
→
335 close(fdin);
336 return (NULL((void *)0));
337 }
338 switch (vfork()) {
7
←
Control jumps to 'case 0:' at line 344
→
339 case -1: /* error */
340 (void)close(pdes[0]);
341 (void)close(pdes[1]);
342 close(fdin);
343 return (NULL((void *)0));
344 case 0:
345 dup2(fdin, STDIN_FILENO0);
8
←
This function call is prohibited after a successful vfork
346 /* child -- set stdout to pipe input */
347 if (pdes[1] != STDOUT_FILENO1) {
348 (void)dup2(pdes[1], STDOUT_FILENO1);
349 (void)close(pdes[1]);
350 }
351 (void)close(pdes[0]);
352 /*
353 * Set stderr to /dev/null. Necessary so that cron does not
354 * wait for cpp to finish if it's running calendar -a.
355 */
356 if (doall) {
357 int fderr;
358 fderr = open(_PATH_DEVNULL"/dev/null", O_WRONLY0x0001);
359 if (fderr == -1)
360 _exit(0);
361 (void)dup2(fderr, STDERR_FILENO2);
362 (void)close(fderr);
363 }
364 execl(_PATH_CPP"/usr/libexec/cpp", "cpp", "-traditional", "-undef", "-U__GNUC__",
365 "-P", "-I.", "-w", _PATH_INCLUDE"-I/usr/share/calendar", (char *)NULL((void *)0));
366 warn(_PATH_CPP"/usr/libexec/cpp");
367 _exit(1);
368 }
369 /* parent -- set stdin to pipe output */
370 (void)dup2(pdes[0], STDIN_FILENO0);
371 (void)close(pdes[0]);
372 (void)close(pdes[1]);
373
374 /* not reading all calendar files, just set output to stdout */
375 if (!doall)
376 return (stdout(&__sF[1]));
377
378 /* set output to a temporary file, so if no output don't send mail */
379 return(tmpfile());
380}
381
382void
383closecal(FILE *fp)
384{
385 struct stat sbuf;
386 int nread, pdes[2], status;
387 char buf[1024];
388 pid_t pid = -1;
389
390 if (!doall)
391 return;
392
393 (void)rewind(fp);
394 if (fstat(fileno(fp)(!__isthreaded ? ((fp)->_file) : (fileno)(fp)), &sbuf) || !sbuf.st_size)
395 goto done;
396 if (pipe(pdes) == -1)
397 goto done;
398 switch ((pid = vfork())) {
399 case -1: /* error */
400 (void)close(pdes[0]);
401 (void)close(pdes[1]);
402 goto done;
403 case 0:
404 /* child -- set stdin to pipe output */
405 if (pdes[0] != STDIN_FILENO0) {
406 (void)dup2(pdes[0], STDIN_FILENO0);
407 (void)close(pdes[0]);
408 }
409 (void)close(pdes[1]);
410 execl(_PATH_SENDMAIL"/usr/sbin/sendmail", "sendmail", "-i", "-t", "-F",
411 "\"Reminder Service\"", (char *)NULL((void *)0));
412 warn(_PATH_SENDMAIL"/usr/sbin/sendmail");
413 _exit(1);
414 }
415 /* parent -- write to pipe input */
416 (void)close(pdes[0]);
417
418 header[1].iov_base = header[3].iov_base = pw->pw_name;
419 header[1].iov_len = header[3].iov_len = strlen(pw->pw_name);
420 writev(pdes[1], header, 8);
421 while ((nread = read(fileno(fp)(!__isthreaded ? ((fp)->_file) : (fileno)(fp)), buf, sizeof(buf))) > 0)
422 (void)write(pdes[1], buf, nread);
423 (void)close(pdes[1]);
424done: (void)fclose(fp);
425 if (pid != -1) {
426 while (waitpid(pid, &status, 0) == -1) {
427 if (errno(*__errno()) != EINTR4)
428 break;
429 }
430 }
431}
432
433
434void
435insert(struct event **head, struct event *cur_evt)
436{
437 struct event *tmp, *tmp2;
438
439 if (*head) {
440 /* Insert this one in order */
441 tmp = *head;
442 tmp2 = NULL((void *)0);
443 while (tmp->next &&
444 tmp->when <= cur_evt->when) {
445 tmp2 = tmp;
446 tmp = tmp->next;
447 }
448 if (tmp->when > cur_evt->when) {
449 cur_evt->next = tmp;
450 if (tmp2)
451 tmp2->next = cur_evt;
452 else
453 *head = cur_evt;
454 } else {
455 cur_evt->next = tmp->next;
456 tmp->next = cur_evt;
457 }
458 } else {
459 *head = cur_evt;
460 cur_evt->next = NULL((void *)0);
461 }
462}