Bug Summary

File:src/lib/libc/stdlib/system.c
Warning:line 61, 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 system.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 -fhalf-no-semantic-interposition -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 -D PIC -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/stdlib/system.c
1/* $OpenBSD: system.c,v 1.12 2016/03/13 18:34:21 guenther Exp $ */
2/*
3 * Copyright (c) 1988 The Regents of the University of California.
4 * 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/wait.h>
33#include <errno(*__errno()).h>
34#include <signal.h>
35#include <stdlib.h>
36#include <unistd.h>
37#include <paths.h>
38
39int
40system(const char *command)
41{
42 pid_t pid, cpid;
43 struct sigaction intsave, quitsave;
44 sigset_t mask, omask;
45 int pstat;
46 char *argp[] = {"sh", "-c", NULL((void *)0), NULL((void *)0)};
47
48 if (!command) /* just checking... */
1
Assuming 'command' is non-null
2
Taking false branch
49 return(1);
50
51 argp[2] = (char *)command;
52
53 sigemptyset(&mask);
54 sigaddset(&mask, SIGCHLD20);
55 sigprocmask(SIG_BLOCK1, &mask, &omask);
56 switch (cpid = vfork()) {
3
Control jumps to 'case 0:' at line 60
57 case -1: /* error */
58 sigprocmask(SIG_SETMASK3, &omask, NULL((void *)0));
59 return(-1);
60 case 0: /* child */
61 sigprocmask(SIG_SETMASK3, &omask, NULL((void *)0));
4
This function call is prohibited after a successful vfork
62 execve(_PATH_BSHELL"/bin/sh", argp, environ);
63 _exit(127);
64 }
65
66 sigaction(SIGINT2, NULL((void *)0), &intsave);
67 sigaction(SIGQUIT3, NULL((void *)0), &quitsave);
68 do {
69 pid = waitpid(cpid, &pstat, 0);
70 } while (pid == -1 && errno(*__errno()) == EINTR4);
71 sigprocmask(SIG_SETMASK3, &omask, NULL((void *)0));
72 sigaction(SIGINT2, &intsave, NULL((void *)0));
73 sigaction(SIGQUIT3, &quitsave, NULL((void *)0));
74 return (pid == -1 ? -1 : pstat);
75}
76DEF_STRONG(system)__asm__(".global " "system" " ; " "system" " = " "_libc_system"
)
;