d/freebsd-dev
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity
29c8295312
freebsd-dev/sbin/mount_fusefs/mount_fusefs.c
Alan Somers 8c50ee012f mount_fusefs: fix a segfault on memory allocation failure 
Reported by:	Coverity
Coverity CID:	1354188
MFC after:	4 days
Sponsored by:	The FreeBSD Foundation
2019-09-07 21:49:01 +00:00

497 lines
13 KiB
C
Raw Blame History

/*-
* SPDX-License-Identifier: BSD-2-Clause-FreeBSD
*
* Copyright (c) 2005 Jean-Sebastien Pedron
* Copyright (c) 2005 Csaba Henk
* All rights reserved.
*
* Copyright (c) 2019 The FreeBSD Foundation
*
* Portions of this software were developed by BFF Storage Systems under
* sponsorship from the FreeBSD Foundation.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/param.h>
#include <sys/mount.h>
#include <sys/uio.h>
#include <sys/stat.h>
#include <sys/sysctl.h>
#include <err.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sysexits.h>
#include <unistd.h>
#include <fcntl.h>
#include <signal.h>
#include <getopt.h>
#include <limits.h>
#include <osreldate.h>
#include <paths.h>
#include "mntopts.h"
#ifndef FUSE4BSD_VERSION
#define FUSE4BSD_VERSION "0.3.9-pre1"
#endif
void __usage_short(void);
void usage(void);
void helpmsg(void);
void showversion(void);
static struct mntopt mopts[] = {
#define ALTF_PRIVATE 0x01
{ "private", 0, ALTF_PRIVATE, 1 },
{ "neglect_shares", 0, 0x02, 1 },
{ "push_symlinks_in", 0, 0x04, 1 },
{ "allow_other", 0, 0x08, 1 },
{ "default_permissions", 0, 0x10, 1 },
#define ALTF_MAXREAD 0x20
{ "max_read=", 0, ALTF_MAXREAD, 1 },
#define ALTF_SUBTYPE 0x40
{ "subtype=", 0, ALTF_SUBTYPE, 1 },
/*
* MOPT_AUTOMOUNTED, included by MOPT_STDOPTS, does not fit into
* the 'flags' argument to nmount(2). We have to abuse altflags
* to pass it, as string, via iovec.
*/
#define ALTF_AUTOMOUNTED 0x100
{ "automounted", 0, ALTF_AUTOMOUNTED, 1 },
#define ALTF_INTR 0x200
{ "intr", 0, ALTF_INTR, 1 },
/* Linux specific options, we silently ignore them */
{ "fsname=", 0, 0x00, 1 },
{ "fd=", 0, 0x00, 1 },
{ "rootmode=", 0, 0x00, 1 },
{ "user_id=", 0, 0x00, 1 },
{ "group_id=", 0, 0x00, 1 },
{ "large_read", 0, 0x00, 1 },
/* "nonempty", just the first two chars are stripped off during parsing */
{ "nempty", 0, 0x00, 1 },
{ "async", 0, MNT_ASYNC, 0},
{ "noasync", 1, MNT_ASYNC, 0},
MOPT_STDOPTS,
MOPT_END
};
struct mntval {
int mv_flag;
void *mv_value;
int mv_len;
};
static struct mntval mvals[] = {
{ ALTF_MAXREAD, NULL, 0 },
{ ALTF_SUBTYPE, NULL, 0 },
{ 0, NULL, 0 }
};
#define DEFAULT_MOUNT_FLAGS ALTF_PRIVATE
int
main(int argc, char *argv[])
{
struct iovec *iov;
int mntflags, iovlen, verbose = 0;
char *dev = NULL, *dir = NULL, mntpath[MAXPATHLEN];
char *devo = NULL, *diro = NULL;
char ndev[128], fdstr[15];
int i, done = 0, reject_allow_other = 0, safe_level = 0;
int altflags = DEFAULT_MOUNT_FLAGS;
int __altflags = DEFAULT_MOUNT_FLAGS;
int ch = 0;
struct mntopt *mo;
struct mntval *mv;
static struct option longopts[] = {
{"reject-allow_other", no_argument, NULL, 'A'},
{"safe", no_argument, NULL, 'S'},
{"daemon", required_argument, NULL, 'D'},
{"daemon_opts", required_argument, NULL, 'O'},
{"special", required_argument, NULL, 's'},
{"mountpath", required_argument, NULL, 'm'},
{"version", no_argument, NULL, 'V'},
{"help", no_argument, NULL, 'h'},
{0,0,0,0}
};
int pid = 0;
int fd = -1, fdx;
char *ep;
char *daemon_str = NULL, *daemon_opts = NULL;
/*
* We want a parsing routine which is not sensitive to
* the position of args/opts; it should extract the
* first two args and stop at the beginning of the rest.
* (This makes it easier to call mount_fusefs from external
* utils than it is with a strict "util flags args" syntax.)
*/
iov = NULL;
iovlen = 0;
mntflags = 0;
/* All in all, I feel it more robust this way... */
unsetenv("POSIXLY_CORRECT");
if (getenv("MOUNT_FUSEFS_IGNORE_UNKNOWN"))
getmnt_silent = 1;
if (getenv("MOUNT_FUSEFS_VERBOSE"))
verbose = 1;
do {
for (i = 0; i < 3; i++) {
if (optind < argc && argv[optind][0] != '-') {
if (dir) {
done = 1;
break;
}
if (dev)
dir = argv[optind];
else
dev = argv[optind];
optind++;
}
}
switch(ch) {
case 'A':
reject_allow_other = 1;
break;
case 'S':
safe_level = 1;
break;
case 'D':
if (daemon_str)
errx(1, "daemon specified inconsistently");
daemon_str = optarg;
break;
case 'O':
if (daemon_opts)
errx(1, "daemon opts specified inconsistently");
daemon_opts = optarg;
break;
case 'o':
getmntopts(optarg, mopts, &mntflags, &altflags);
for (mv = mvals; mv->mv_flag; ++mv) {
if (! (altflags & mv->mv_flag))
continue;
for (mo = mopts; mo->m_flag; ++mo) {
char *p, *q;
if (mo->m_flag != mv->mv_flag)
continue;
p = strstr(optarg, mo->m_option);
if (p) {
p += strlen(mo->m_option);
q = p;
while (*q != '\0' && *q != ',')
q++;
mv->mv_len = q - p + 1;
mv->mv_value = malloc(mv->mv_len);
if (mv->mv_value == NULL)
err(1, "malloc");
memcpy(mv->mv_value, p, mv->mv_len - 1);
((char *)mv->mv_value)[mv->mv_len - 1] = '\0';
break;
}
}
}
break;
case 's':
if (devo)
errx(1, "special specified inconsistently");
devo = optarg;
break;
case 'm':
if (diro)
errx(1, "mount path specified inconsistently");
diro = optarg;
break;
case 'v':
verbose = 1;
break;
case 'h':
helpmsg();
break;
case 'V':
showversion();
break;
case '\0':
break;
case '?':
default:
usage();
}
if (done)
break;
} while ((ch = getopt_long(argc, argv, "AvVho:SD:O:s:m:", longopts, NULL)) != -1);
argc -= optind;
argv += optind;
if (devo) {
if (dev)
errx(1, "special specified inconsistently");
dev = devo;
} else if (diro)
errx(1, "if mountpoint is given via an option, special should also be given via an option");
if (diro) {
if (dir)
errx(1, "mount path specified inconsistently");
dir = diro;
}
if ((! dev) && argc > 0) {
dev = *argv++;
argc--;
}
if ((! dir) && argc > 0) {
dir = *argv++;
argc--;
}
if (! (dev && dir))
errx(1, "missing special and/or mountpoint");
for (mo = mopts; mo->m_flag; ++mo) {
if (altflags & mo->m_flag) {
int iov_done = 0;
if (reject_allow_other &&
strcmp(mo->m_option, "allow_other") == 0)
/*
* reject_allow_other is stronger than a
* negative of allow_other: if this is set,
* allow_other is blocked, period.
*/
errx(1, "\"allow_other\" usage is banned by respective option");
for (mv = mvals; mv->mv_flag; ++mv) {
if (mo->m_flag != mv->mv_flag)
continue;
if (mv->mv_value) {
build_iovec(&iov, &iovlen, mo->m_option, mv->mv_value, mv->mv_len);
iov_done = 1;
break;
}
}
if (! iov_done)
build_iovec(&iov, &iovlen, mo->m_option,
__DECONST(void *, ""), -1);
}
if (__altflags & mo->m_flag) {
char *uscore_opt;
if (asprintf(&uscore_opt, "__%s", mo->m_option) == -1)
err(1, "failed to allocate memory");
build_iovec(&iov, &iovlen, uscore_opt,
__DECONST(void *, ""), -1);
free(uscore_opt);
}
}
if (getenv("MOUNT_FUSEFS_SAFE"))
safe_level = 1;
if (safe_level > 0 && (argc > 0 || daemon_str || daemon_opts))
errx(1, "safe mode, spawning daemon not allowed");
if ((argc > 0 && (daemon_str || daemon_opts)) ||
(daemon_opts && ! daemon_str))
errx(1, "daemon specified inconsistently");
/*
* Resolve the mountpoint with realpath(3) and remove unnecessary
* slashes from the devicename if there are any.
*/
if (checkpath(dir, mntpath) != 0)
err(1, "%s", mntpath);
(void)rmslashes(dev, dev);
if (strcmp(dev, "auto") == 0)
dev = __DECONST(char *, "/dev/fuse");
if (strcmp(dev, "/dev/fuse") == 0) {
if (! (argc > 0 || daemon_str)) {
fprintf(stderr, "Please also specify the fuse daemon to run when mounting via the multiplexer!\n");
usage();
}
if ((fd = open(dev, O_RDWR)) < 0)
err(1, "failed to open fuse device");
} else {
fdx = strtol(dev, &ep, 10);
if (*ep == '\0')
fd = fdx;
}
/* Identifying device */
if (fd >= 0) {
struct stat sbuf;
char *ndevbas, *lep;
if (fstat(fd, &sbuf) == -1)
err(1, "cannot stat device file descriptor");
strcpy(ndev, _PATH_DEV);
ndevbas = ndev + strlen(_PATH_DEV);
devname_r(sbuf.st_rdev, S_IFCHR, ndevbas,
sizeof(ndev) - strlen(_PATH_DEV));
if (strncmp(ndevbas, "fuse", 4))
errx(1, "mounting inappropriate device");
strtol(ndevbas + 4, &lep, 10);
if (*lep != '\0')
errx(1, "mounting inappropriate device");
dev = ndev;
}
if (argc > 0 || daemon_str) {
char *fds;
if (fd < 0 && (fd = open(dev, O_RDWR)) < 0)
err(1, "failed to open fuse device");
if (asprintf(&fds, "%d", fd) == -1)
err(1, "failed to allocate memory");
setenv("FUSE_DEV_FD", fds, 1);
free(fds);
setenv("FUSE_NO_MOUNT", "1", 1);
if (daemon_str) {
char *bgdaemon;
int len;
if (! daemon_opts)
daemon_opts = __DECONST(char *, "");
len = strlen(daemon_str) + 1 + strlen(daemon_opts) +
2 + 1;
bgdaemon = calloc(1, len);
if (! bgdaemon)
err(1, "failed to allocate memory");
strlcpy(bgdaemon, daemon_str, len);
strlcat(bgdaemon, " ", len);
strlcat(bgdaemon, daemon_opts, len);
strlcat(bgdaemon, " &", len);
if (system(bgdaemon))
err(1, "failed to call fuse daemon");
} else {
if ((pid = fork()) < 0)
err(1, "failed to fork for fuse daemon");
if (pid == 0) {
execvp(argv[0], argv);
err(1, "failed to exec fuse daemon");
}
}
}
/* Prepare the options vector for nmount(). build_iovec() is declared
* in mntopts.h. */
sprintf(fdstr, "%d", fd);
build_iovec(&iov, &iovlen, "fstype", __DECONST(void *, "fusefs"), -1);
build_iovec(&iov, &iovlen, "fspath", mntpath, -1);
build_iovec(&iov, &iovlen, "from", dev, -1);
build_iovec(&iov, &iovlen, "fd", fdstr, -1);
if (verbose)
fprintf(stderr, "mounting fuse daemon on device %s\n", dev);
if (nmount(iov, iovlen, mntflags) < 0)
err(EX_OSERR, "%s on %s", dev, mntpath);
exit(0);
}
void
__usage_short(void) {
fprintf(stderr,
"usage:\n%s [-A|-S|-v|-V|-h|-D daemon|-O args|-s special|-m node|-o option...] special node [daemon args...]\n\n",
getprogname());
}
void
usage(void)
{
struct mntopt *mo;
__usage_short();
fprintf(stderr, "known options:\n");
for (mo = mopts; mo->m_flag; ++mo)
fprintf(stderr, "\t%s\n", mo->m_option);
fprintf(stderr, "\n(use -h for a detailed description of these options)\n");
exit(EX_USAGE);
}
void
helpmsg(void)
{
if (! getenv("MOUNT_FUSEFS_CALL_BY_LIB")) {
__usage_short();
fprintf(stderr, "description of options:\n");
}
/*
* The main use case of this function is giving info embedded in general
* FUSE lib help output. Therefore the style and the content of the output
* tries to fit there as much as possible.
*/
fprintf(stderr,
" -o allow_other allow access to other users\n"
/* " -o nonempty allow mounts over non-empty file/dir\n" */
" -o default_permissions enable permission checking by kernel\n"
" -o intr interruptible mount\n"
/*
" -o fsname=NAME set filesystem name\n"
" -o large_read issue large read requests (2.4 only)\n"
*/
" -o subtype=NAME set filesystem type\n"
" -o max_read=N set maximum size of read requests\n"
" -o noprivate allow secondary mounting of the filesystem\n"
" -o neglect_shares don't report EBUSY when unmount attempted\n"
" in presence of secondary mounts\n"
" -o push_symlinks_in prefix absolute symlinks with mountpoint\n"
);
exit(EX_USAGE);
}
void
showversion(void)
{
puts("mount_fusefs [fuse4bsd] version: " FUSE4BSD_VERSION);
exit(EX_USAGE);
}
Reference in New Issue View Git Blame Copy Permalink