freebsd-dev/sbin/umount/umount.c
Eitan Adler c27063b934 Fix memory leak in umount.c
PR:		bin/172553
Submitted by:	Erik Cederstrand <erik@cederstrand.dk>
Approved by:	cperciva
MFC after:	3 days
2012-11-15 15:06:21 +00:00

616 lines
15 KiB
C

/*-
* Copyright (c) 1980, 1989, 1993
* The Regents of the University of California. All rights reserved.
*
* 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.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS 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 REGENTS 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.
*/
#ifndef lint
static const char copyright[] =
"@(#) Copyright (c) 1980, 1989, 1993\n\
The Regents of the University of California. All rights reserved.\n";
#endif /* not lint */
#ifndef lint
#if 0
static char sccsid[] = "@(#)umount.c 8.8 (Berkeley) 5/8/95";
#endif
static const char rcsid[] =
"$FreeBSD$";
#endif /* not lint */
#include <sys/param.h>
#include <sys/mount.h>
#include <sys/socket.h>
#include <sys/stat.h>
#include <netdb.h>
#include <rpc/rpc.h>
#include <rpcsvc/mount.h>
#include <ctype.h>
#include <err.h>
#include <errno.h>
#include <fstab.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include "mounttab.h"
typedef enum { FIND, REMOVE, CHECKUNIQUE } dowhat;
static struct addrinfo *nfshost_ai = NULL;
static int fflag, vflag;
static char *nfshost;
struct statfs *checkmntlist(char *);
int checkvfsname (const char *, char **);
struct statfs *getmntentry(const char *fromname, const char *onname,
fsid_t *fsid, dowhat what);
char **makevfslist (const char *);
size_t mntinfo (struct statfs **);
int namematch (struct addrinfo *);
int parsehexfsid(const char *hex, fsid_t *fsid);
int sacmp (void *, void *);
int umountall (char **);
int checkname (char *, char **);
int umountfs(struct statfs *sfs);
void usage (void);
int xdr_dir (XDR *, char *);
int
main(int argc, char *argv[])
{
int all, errs, ch, mntsize, error;
char **typelist = NULL;
struct statfs *mntbuf, *sfs;
struct addrinfo hints;
all = errs = 0;
while ((ch = getopt(argc, argv, "AaF:fh:t:v")) != -1)
switch (ch) {
case 'A':
all = 2;
break;
case 'a':
all = 1;
break;
case 'F':
setfstab(optarg);
break;
case 'f':
fflag = MNT_FORCE;
break;
case 'h': /* -h implies -A. */
all = 2;
nfshost = optarg;
break;
case 't':
if (typelist != NULL)
err(1, "only one -t option may be specified");
typelist = makevfslist(optarg);
break;
case 'v':
vflag = 1;
break;
default:
usage();
/* NOTREACHED */
}
argc -= optind;
argv += optind;
/* Start disks transferring immediately. */
if ((fflag & MNT_FORCE) == 0)
sync();
if ((argc == 0 && !all) || (argc != 0 && all))
usage();
/* -h implies "-t nfs" if no -t flag. */
if ((nfshost != NULL) && (typelist == NULL))
typelist = makevfslist("nfs");
if (nfshost != NULL) {
memset(&hints, 0, sizeof hints);
error = getaddrinfo(nfshost, NULL, &hints, &nfshost_ai);
if (error)
errx(1, "%s: %s", nfshost, gai_strerror(error));
}
switch (all) {
case 2:
if ((mntsize = mntinfo(&mntbuf)) <= 0)
break;
/*
* We unmount the nfs-mounts in the reverse order
* that they were mounted.
*/
for (errs = 0, mntsize--; mntsize > 0; mntsize--) {
sfs = &mntbuf[mntsize];
if (checkvfsname(sfs->f_fstypename, typelist))
continue;
if (strcmp(sfs->f_mntonname, "/dev") == 0)
continue;
if (umountfs(sfs) != 0)
errs = 1;
}
free(mntbuf);
break;
case 1:
if (setfsent() == 0)
err(1, "%s", getfstab());
errs = umountall(typelist);
break;
case 0:
for (errs = 0; *argv != NULL; ++argv)
if (checkname(*argv, typelist) != 0)
errs = 1;
break;
}
exit(errs);
}
int
umountall(char **typelist)
{
struct xvfsconf vfc;
struct fstab *fs;
int rval;
char *cp;
static int firstcall = 1;
if ((fs = getfsent()) != NULL)
firstcall = 0;
else if (firstcall)
errx(1, "fstab reading failure");
else
return (0);
do {
/* Ignore the root. */
if (strcmp(fs->fs_file, "/") == 0)
continue;
/*
* !!!
* Historic practice: ignore unknown FSTAB_* fields.
*/
if (strcmp(fs->fs_type, FSTAB_RW) &&
strcmp(fs->fs_type, FSTAB_RO) &&
strcmp(fs->fs_type, FSTAB_RQ))
continue;
/* Ignore unknown file system types. */
if (getvfsbyname(fs->fs_vfstype, &vfc) == -1)
continue;
if (checkvfsname(fs->fs_vfstype, typelist))
continue;
/*
* We want to unmount the file systems in the reverse order
* that they were mounted. So, we save off the file name
* in some allocated memory, and then call recursively.
*/
if ((cp = malloc((size_t)strlen(fs->fs_file) + 1)) == NULL)
err(1, "malloc failed");
(void)strcpy(cp, fs->fs_file);
rval = umountall(typelist);
rval = checkname(cp, typelist) || rval;
free(cp);
return (rval);
} while ((fs = getfsent()) != NULL);
return (0);
}
/*
* Do magic checks on mountpoint/device/fsid, and then call unmount(2).
*/
int
checkname(char *mntname, char **typelist)
{
char buf[MAXPATHLEN];
struct statfs sfsbuf;
struct stat sb;
struct statfs *sfs;
char *delimp;
dev_t dev;
int len;
/*
* 1. Check if the name exists in the mounttable.
*/
sfs = checkmntlist(mntname);
/*
* 2. Remove trailing slashes if there are any. After that
* we look up the name in the mounttable again.
*/
if (sfs == NULL) {
len = strlen(mntname);
while (len > 1 && mntname[len - 1] == '/')
mntname[--len] = '\0';
sfs = checkmntlist(mntname);
}
/*
* 3. Check if the deprecated NFS syntax with an '@' has been used
* and translate it to the ':' syntax. Look up the name in the
* mount table again.
*/
if (sfs == NULL && (delimp = strrchr(mntname, '@')) != NULL) {
snprintf(buf, sizeof(buf), "%s:%.*s", delimp + 1,
(int)(delimp - mntname), mntname);
len = strlen(buf);
while (len > 1 && buf[len - 1] == '/')
buf[--len] = '\0';
sfs = checkmntlist(buf);
}
/*
* 4. Resort to a statfs(2) call. This is the last check so that
* hung NFS filesystems for example can be unmounted without
* potentially blocking forever in statfs() as long as the
* filesystem is specified unambiguously. This covers all the
* hard cases such as symlinks and mismatches between the
* mount list and reality.
* We also do this if an ambiguous mount point was specified.
*/
if (sfs == NULL || (getmntentry(NULL, mntname, NULL, FIND) != NULL &&
getmntentry(NULL, mntname, NULL, CHECKUNIQUE) == NULL)) {
if (statfs(mntname, &sfsbuf) != 0) {
warn("%s: statfs", mntname);
} else if (stat(mntname, &sb) != 0) {
warn("%s: stat", mntname);
} else if (S_ISDIR(sb.st_mode)) {
/* Check that `mntname' is the root directory. */
dev = sb.st_dev;
snprintf(buf, sizeof(buf), "%s/..", mntname);
if (stat(buf, &sb) != 0) {
warn("%s: stat", buf);
} else if (sb.st_dev == dev) {
warnx("%s: not a file system root directory",
mntname);
return (1);
} else
sfs = &sfsbuf;
}
}
if (sfs == NULL) {
warnx("%s: unknown file system", mntname);
return (1);
}
if (checkvfsname(sfs->f_fstypename, typelist))
return (1);
return (umountfs(sfs));
}
/*
* NFS stuff and unmount(2) call
*/
int
umountfs(struct statfs *sfs)
{
char fsidbuf[64];
enum clnt_stat clnt_stat;
struct timeval try;
struct addrinfo *ai, hints;
int do_rpc;
CLIENT *clp;
char *nfsdirname, *orignfsdirname;
char *hostp, *delimp;
ai = NULL;
do_rpc = 0;
hostp = NULL;
nfsdirname = delimp = orignfsdirname = NULL;
memset(&hints, 0, sizeof hints);
if (strcmp(sfs->f_fstypename, "nfs") == 0) {
if ((nfsdirname = strdup(sfs->f_mntfromname)) == NULL)
err(1, "strdup");
orignfsdirname = nfsdirname;
if (*nfsdirname == '[' &&
(delimp = strchr(nfsdirname + 1, ']')) != NULL &&
*(delimp + 1) == ':') {
hostp = nfsdirname + 1;
nfsdirname = delimp + 2;
} else if ((delimp = strrchr(nfsdirname, ':')) != NULL) {
hostp = nfsdirname;
nfsdirname = delimp + 1;
}
if (hostp != NULL) {
*delimp = '\0';
getaddrinfo(hostp, NULL, &hints, &ai);
if (ai == NULL) {
warnx("can't get net id for host");
}
}
/*
* Check if we have to start the rpc-call later.
* If there are still identical nfs-names mounted,
* we skip the rpc-call. Obviously this has to
* happen before unmount(2), but it should happen
* after the previous namecheck.
* A non-NULL return means that this is the last
* mount from mntfromname that is still mounted.
*/
if (getmntentry(sfs->f_mntfromname, NULL, NULL,
CHECKUNIQUE) != NULL)
do_rpc = 1;
}
if (!namematch(ai)) {
free(orignfsdirname);
return (1);
}
/* First try to unmount using the file system ID. */
snprintf(fsidbuf, sizeof(fsidbuf), "FSID:%d:%d", sfs->f_fsid.val[0],
sfs->f_fsid.val[1]);
if (unmount(fsidbuf, fflag | MNT_BYFSID) != 0) {
/* XXX, non-root users get a zero fsid, so don't warn. */
if (errno != ENOENT || sfs->f_fsid.val[0] != 0 ||
sfs->f_fsid.val[1] != 0)
warn("unmount of %s failed", sfs->f_mntonname);
if (errno != ENOENT) {
free(orignfsdirname);
return (1);
}
/* Compatibility for old kernels. */
if (sfs->f_fsid.val[0] != 0 || sfs->f_fsid.val[1] != 0)
warnx("retrying using path instead of file system ID");
if (unmount(sfs->f_mntonname, fflag) != 0) {
warn("unmount of %s failed", sfs->f_mntonname);
free(orignfsdirname);
return (1);
}
}
/* Mark this this file system as unmounted. */
getmntentry(NULL, NULL, &sfs->f_fsid, REMOVE);
if (vflag)
(void)printf("%s: unmount from %s\n", sfs->f_mntfromname,
sfs->f_mntonname);
/*
* Report to mountd-server which nfsname
* has been unmounted.
*/
if (ai != NULL && !(fflag & MNT_FORCE) && do_rpc) {
clp = clnt_create(hostp, MOUNTPROG, MOUNTVERS, "udp");
if (clp == NULL) {
warnx("%s: %s", hostp,
clnt_spcreateerror("MOUNTPROG"));
free(orignfsdirname);
return (1);
}
clp->cl_auth = authsys_create_default();
try.tv_sec = 20;
try.tv_usec = 0;
clnt_stat = clnt_call(clp, MOUNTPROC_UMNT, (xdrproc_t)xdr_dir,
nfsdirname, (xdrproc_t)xdr_void, (caddr_t)0, try);
if (clnt_stat != RPC_SUCCESS) {
warnx("%s: %s", hostp,
clnt_sperror(clp, "RPCMNT_UMOUNT"));
free(orignfsdirname);
return (1);
}
/*
* Remove the unmounted entry from /var/db/mounttab.
*/
if (read_mtab()) {
clean_mtab(hostp, nfsdirname, vflag);
if(!write_mtab(vflag))
warnx("cannot remove mounttab entry %s:%s",
hostp, nfsdirname);
free_mtab();
}
auth_destroy(clp->cl_auth);
clnt_destroy(clp);
}
free(orignfsdirname);
return (0);
}
struct statfs *
getmntentry(const char *fromname, const char *onname, fsid_t *fsid, dowhat what)
{
static struct statfs *mntbuf;
static size_t mntsize = 0;
static char *mntcheck = NULL;
struct statfs *sfs, *foundsfs;
int i, count;
if (mntsize <= 0) {
if ((mntsize = mntinfo(&mntbuf)) <= 0)
return (NULL);
}
if (mntcheck == NULL) {
if ((mntcheck = calloc(mntsize + 1, sizeof(int))) == NULL)
err(1, "calloc");
}
/*
* We want to get the file systems in the reverse order
* that they were mounted. Unmounted file systems are marked
* in a table called 'mntcheck'.
*/
count = 0;
foundsfs = NULL;
for (i = mntsize - 1; i >= 0; i--) {
if (mntcheck[i])
continue;
sfs = &mntbuf[i];
if (fromname != NULL && strcmp(sfs->f_mntfromname,
fromname) != 0)
continue;
if (onname != NULL && strcmp(sfs->f_mntonname, onname) != 0)
continue;
if (fsid != NULL && bcmp(&sfs->f_fsid, fsid,
sizeof(*fsid)) != 0)
continue;
switch (what) {
case CHECKUNIQUE:
foundsfs = sfs;
count++;
continue;
case REMOVE:
mntcheck[i] = 1;
break;
default:
break;
}
return (sfs);
}
if (what == CHECKUNIQUE && count == 1)
return (foundsfs);
return (NULL);
}
int
sacmp(void *sa1, void *sa2)
{
void *p1, *p2;
int len;
if (((struct sockaddr *)sa1)->sa_family !=
((struct sockaddr *)sa2)->sa_family)
return (1);
switch (((struct sockaddr *)sa1)->sa_family) {
case AF_INET:
p1 = &((struct sockaddr_in *)sa1)->sin_addr;
p2 = &((struct sockaddr_in *)sa2)->sin_addr;
len = 4;
break;
case AF_INET6:
p1 = &((struct sockaddr_in6 *)sa1)->sin6_addr;
p2 = &((struct sockaddr_in6 *)sa2)->sin6_addr;
len = 16;
if (((struct sockaddr_in6 *)sa1)->sin6_scope_id !=
((struct sockaddr_in6 *)sa2)->sin6_scope_id)
return (1);
break;
default:
return (1);
}
return memcmp(p1, p2, len);
}
int
namematch(struct addrinfo *ai)
{
struct addrinfo *aip;
if (nfshost == NULL || nfshost_ai == NULL)
return (1);
while (ai != NULL) {
aip = nfshost_ai;
while (aip != NULL) {
if (sacmp(ai->ai_addr, aip->ai_addr) == 0)
return (1);
aip = aip->ai_next;
}
ai = ai->ai_next;
}
return (0);
}
struct statfs *
checkmntlist(char *mntname)
{
struct statfs *sfs;
fsid_t fsid;
sfs = NULL;
if (parsehexfsid(mntname, &fsid) == 0)
sfs = getmntentry(NULL, NULL, &fsid, FIND);
if (sfs == NULL)
sfs = getmntentry(NULL, mntname, NULL, FIND);
if (sfs == NULL)
sfs = getmntentry(mntname, NULL, NULL, FIND);
return (sfs);
}
size_t
mntinfo(struct statfs **mntbuf)
{
static struct statfs *origbuf;
size_t bufsize;
int mntsize;
mntsize = getfsstat(NULL, 0, MNT_NOWAIT);
if (mntsize <= 0)
return (0);
bufsize = (mntsize + 1) * sizeof(struct statfs);
if ((origbuf = malloc(bufsize)) == NULL)
err(1, "malloc");
mntsize = getfsstat(origbuf, (long)bufsize, MNT_NOWAIT);
*mntbuf = origbuf;
return (mntsize);
}
/*
* Convert a hexadecimal filesystem ID to an fsid_t.
* Returns 0 on success.
*/
int
parsehexfsid(const char *hex, fsid_t *fsid)
{
char hexbuf[3];
int i;
if (strlen(hex) != sizeof(*fsid) * 2)
return (-1);
hexbuf[2] = '\0';
for (i = 0; i < (int)sizeof(*fsid); i++) {
hexbuf[0] = hex[i * 2];
hexbuf[1] = hex[i * 2 + 1];
if (!isxdigit(hexbuf[0]) || !isxdigit(hexbuf[1]))
return (-1);
((u_char *)fsid)[i] = strtol(hexbuf, NULL, 16);
}
return (0);
}
/*
* xdr routines for mount rpc's
*/
int
xdr_dir(XDR *xdrsp, char *dirp)
{
return (xdr_string(xdrsp, &dirp, MNTPATHLEN));
}
void
usage(void)
{
(void)fprintf(stderr, "%s\n%s\n",
"usage: umount [-fv] special ... | node ... | fsid ...",
" umount -a | -A [-F fstab] [-fv] [-h host] [-t type]");
exit(1);
}