/usr/src/lib/libc/gen/exec.c

Bug Summary

File:	src/lib/libc/gen/exec.c
Warning:	line 278, column 3 2nd function call argument is an uninitialized value

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 exec.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/lib/libc/obj -resource-dir /usr/local/lib/clang/13.0.0 -include namespace.h -I /usr/src/lib/libc/include -I /usr/src/lib/libc/hidden -D __LIBC__ -D APIWARN -D YP -I /usr/src/lib/libc/yp -I /usr/src/lib/libc -I /usr/src/lib/libc/gdtoa -I /usr/src/lib/libc/arch/amd64/gdtoa -D INFNAN_CHECK -D MULTIPLE_THREADS -D NO_FENV_H -D USE_LOCALE -I /usr/src/lib/libc -I /usr/src/lib/libc/citrus -D RESOLVSORT -D FLOATING_POINT -D PRINTF_WIDE_CHAR -D SCANF_WIDE_CHAR -D FUTEX -internal-isystem /usr/local/lib/clang/13.0.0/include -internal-externc-isystem /usr/include -O2 -fdebug-compilation-dir=/usr/src/lib/libc/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/lib/libc/gen/exec.c

1/*	$OpenBSD: exec.c,v 1.24 2021/09/22 20:40:06 deraadt Exp $ */
2/*-
3 * Copyright (c) 1991, 1993
4 *	The Regents of the University of California.  All rights reserved.
5 *
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
8 * are met:
9 * 1. Redistributions of source code must retain the above copyright
10 *    notice, this list of conditions and the following disclaimer.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 *    notice, this list of conditions and the following disclaimer in the
13 *    documentation and/or other materials provided with the distribution.
14 * 3. Neither the name of the University nor the names of its contributors
15 *    may be used to endorse or promote products derived from this software
16 *    without specific prior written permission.
17 *
18 * THIS SOFTWARE IS PROVIDED BY THE REGENTS 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 REGENTS 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
28 * SUCH DAMAGE.
29 */
30 
31#include <sys/types.h>
32#include <sys/uio.h>
33#include <sys/mman.h>
34 
35#include <errno(*__errno()).h>
36#include <limits.h>
37#include <paths.h>
38#include <stdarg.h>
39#include <stdio.h>
40#include <stdlib.h>
41#include <string.h>
42#include <unistd.h>
43 
44int
45execl(const char *name, const char *arg, ...)
46{
47	va_list ap;
48	char **argv;
49	size_t maplen;
50	int save_errno, n, error;
51 
52	va_start(ap, arg)__builtin_va_start(ap, arg);
53	n = 1;
54	while (va_arg(ap, char *)__builtin_va_arg(ap, char *) != NULL((void *)0))
55		n++;
56	va_end(ap)__builtin_va_end(ap);
57 
58	maplen = (n + 1) * sizeof(*argv);
59	argv = mmap(NULL((void *)0), maplen, PROT_WRITE0x02|PROT_READ0x01,
60	    MAP_ANON0x1000|MAP_PRIVATE0x0002, -1, 0);
61	if (argv == MAP_FAILED((void *)-1))
62		return (-1);
63 
64	va_start(ap, arg)__builtin_va_start(ap, arg);
65	n = 1;
66	argv[0] = (char *)arg;
67	while ((argv[n] = va_arg(ap, char *)__builtin_va_arg(ap, char *)) != NULL((void *)0))
68		n++;
69	va_end(ap)__builtin_va_end(ap);
70 
71	error = execve(name, argv, environ);
72	save_errno = errno(*__errno());
73	munmap(argv, maplen);
74	errno(*__errno()) = save_errno;
75	return (error);
76}
77DEF_WEAK(execl)__asm__(".weak " "execl" " ; " "execl" " = " "_libc_execl");
78 
79int
80execle(const char *name, const char *arg, ...)
81{
82	va_list ap;
83	char **argv, **envp;
84	size_t maplen;
85	int save_errno, n, error;
86 
87	va_start(ap, arg)__builtin_va_start(ap, arg);
88	n = 1;
89	while (va_arg(ap, char *)__builtin_va_arg(ap, char *) != NULL((void *)0))
90		n++;
91	va_end(ap)__builtin_va_end(ap);
92 
93	maplen = (n + 1) * sizeof(*argv);
94	argv = mmap(NULL((void *)0), maplen, PROT_WRITE0x02|PROT_READ0x01,
95	    MAP_ANON0x1000|MAP_PRIVATE0x0002, -1, 0);
96	if (argv == MAP_FAILED((void *)-1))
97		return (-1);
98 
99	va_start(ap, arg)__builtin_va_start(ap, arg);
100	n = 1;
101	argv[0] = (char *)arg;
102	while ((argv[n] = va_arg(ap, char *)__builtin_va_arg(ap, char *)) != NULL((void *)0))
103		n++;
104	envp = va_arg(ap, char **)__builtin_va_arg(ap, char **);
105	va_end(ap)__builtin_va_end(ap);
106 
107	error = execve(name, argv, envp);
108	save_errno = errno(*__errno());
109	munmap(argv, maplen);
110	errno(*__errno()) = save_errno;
111	return error;
112}
113 
114int
115execlp(const char *name, const char *arg, ...)
116{
117	va_list ap;
118	char **argv;
119	size_t maplen;
120	int save_errno, n, error;
121 
122	va_start(ap, arg)__builtin_va_start(ap, arg);
123	n = 1;
124	while (va_arg(ap, char *)__builtin_va_arg(ap, char *) != NULL((void *)0))
1
Loop condition is false. Execution continues on line 126→
125		n++;
126	va_end(ap)__builtin_va_end(ap);
127 
128	maplen = (n + 1) * sizeof(*argv);
129	argv = mmap(NULL((void *)0), maplen, PROT_WRITE0x02|PROT_READ0x01,
130	    MAP_ANON0x1000|MAP_PRIVATE0x0002, -1, 0);
131	if (argv == MAP_FAILED((void *)-1))
2
←
Assuming the condition is false→
3
←
Taking false branch→
132		return (-1);
133 
134	va_start(ap, arg)__builtin_va_start(ap, arg);
135	n = 1;
136	argv[0] = (char *)arg;
137	while ((argv[n] = va_arg(ap, char *)__builtin_va_arg(ap, char *)) != NULL((void *)0))
4
←
Assuming the condition is false→
5
←
Loop condition is false. Execution continues on line 139→
138		n++;
139	va_end(ap)__builtin_va_end(ap);
140	error = execvp(name, argv);
6
←
Calling 'execvp'→
141	save_errno = errno(*__errno());
142	munmap(argv, maplen);
143	errno(*__errno()) = save_errno;
144	return error;
145}
146 
147int
148execv(const char *name, char *const *argv)
149{
150	(void)execve(name, argv, environ);
151	return (-1);
152}
153 
154int
155execvpe(const char *name, char *const *argv, char *const *envp)
156{
157	char **memp;
158	int cnt;
159	size_t lp, ln, curlen;
8
←
'curlen' declared without an initial value→
160	char *p;
161	int eacces = 0;
162	char *bp, *cur, *path, buf[PATH_MAX1024];
163	size_t maplen;
164	int save_errno, n;
165 
166	/*
167	 * Do not allow null name
168	 */
169	if (name == NULL((void *)0) || *name == '\0') {
9
←
Assuming 'name' is not equal to NULL→
10
←
Assuming the condition is false→
11
←
Taking false branch→
170		errno(*__errno()) = ENOENT2;
171		return (-1);
172 	}
173 
174	/* If it's an absolute or relative path name, it's easy. */
175	if (strchr(name, '/')) {
12
←
Assuming the condition is true→
13
←
Taking true branch→
176		bp = (char *)name;
177		cur = path = NULL((void *)0);
178		goto retry;
14
←
Control jumps to line 228→
179	}
180	bp = buf;
181 
182	/* Get the path we're searching. */
183	if (!(path = getenv("PATH")))
184		path = _PATH_DEFPATH"/usr/bin:/bin:/usr/sbin:/sbin:/usr/X11R6/bin:/usr/local/bin:/usr/local/sbin";
185 
186	curlen = strlen(path) + 1;
187	cur = mmap(NULL((void *)0), curlen, PROT_WRITE0x02|PROT_READ0x01,
188	    MAP_ANON0x1000|MAP_PRIVATE0x0002, -1, 0);
189	if (cur == MAP_FAILED((void *)-1))
190		return (-1);
191 
192	strlcpy(cur, path, curlen);
193	path = cur;
194	while ((p = strsep(&cur, ":"))) {
17
←
Loop condition is false. Execution continues on line 271→
195		/*
196		 * It's a SHELL path -- double, leading and trailing colons
197		 * mean the current directory.
198		 */
199		if (!*p) {
200			p = ".";
201			lp = 1;
202		} else
203			lp = strlen(p);
204		ln = strlen(name);
205 
206		/*
207		 * If the path is too long complain.  This is a possible
208		 * security issue; given a way to make the path too long
209		 * the user may execute the wrong program.
210		 */
211		if (lp + ln + 2 > sizeof(buf)) {
212			struct iovec iov[3];
213 
214			iov[0].iov_base = "execvp: ";
215			iov[0].iov_len = 8;
216			iov[1].iov_base = p;
217			iov[1].iov_len = lp;
218			iov[2].iov_base = ": path too long\n";
219			iov[2].iov_len = 16;
220			(void)writev(STDERR_FILENO2, iov, 3);
221			continue;
222		}
223		bcopy(p, buf, lp);
224		buf[lp] = '/';
225		bcopy(name, buf + lp + 1, ln);
226		buf[lp + ln + 1] = '\0';
227 
228retry:		(void)execve(bp, argv, envp);
229		switch(errno(*__errno())) {
15
←
Control jumps to 'case 20:'  at line 257→
230		case E2BIG7:
231			goto done;
232		case EISDIR21:
233		case ELOOP62:
234		case ENAMETOOLONG63:
235		case ENOENT2:
236			break;
237		case ENOEXEC8:
238			for (cnt = 0; argv[cnt]; ++cnt)
239				;
240 
241			maplen = (cnt + 2) * sizeof(char *);
242			memp = mmap(NULL((void *)0), maplen, PROT_WRITE0x02|PROT_READ0x01,
243			    MAP_ANON0x1000|MAP_PRIVATE0x0002, -1, 0);
244			if (memp == MAP_FAILED((void *)-1))
245				goto done;
246 
247			memp[0] = "sh";
248			memp[1] = bp;
249			bcopy(argv + 1, memp + 2, cnt * sizeof(char *));
250			(void)execve(_PATH_BSHELL"/bin/sh", memp, envp);
251			save_errno = errno(*__errno());
252			munmap(memp, maplen);
253			errno(*__errno()) = save_errno;
254			goto done;
255		case ENOMEM12:
256			goto done;
257		case ENOTDIR20:
258			break;
16
←
 Execution continues on line 194→
259		case ETXTBSY26:
260			/*
261			 * We used to retry here, but sh(1) doesn't.
262			 */
263			goto done;
264		case EACCES13:
265			eacces = 1;
266			break;
267		default:
268			goto done;
269		}
270	}
271	if (eacces17.1
'eacces' is 0
)
18
←
Taking false branch→
272		errno(*__errno()) = EACCES13;
273	else if (!errno(*__errno()))
19
←
Assuming the condition is false→
20
←
Taking false branch→
274		errno(*__errno()) = ENOENT2;
275done:
276	if (cur) {
21
←
Assuming 'cur' is non-null→
22
←
Taking true branch→
277		save_errno = errno(*__errno());
278		munmap(cur, curlen);
23
←
2nd function call argument is an uninitialized value
279		errno(*__errno()) = save_errno;
280	}
281	return (-1);
282}
283DEF_WEAK(execvpe)__asm__(".weak " "execvpe" " ; " "execvpe" " = " "_libc_execvpe"
);
284 
285int
286execvp(const char *name, char *const *argv)
287{
288    return execvpe(name, argv, environ);
7
←
Calling 'execvpe'→
289}
290DEF_WEAK(execvp)__asm__(".weak " "execvp" " ; " "execvp" " = " "_libc_execvp"
);
291 