/*
* Copyright (C) 2010 Karel Zak <kzak@redhat.com>
*
* This file may be redistributed under the terms of the
* GNU Lesser General Public License.
*/
/**
* SECTION: context-umount
* @title: Umount context
* @short_description: high-level API to umount operation.
*/
#include <sys/wait.h>
#include <sys/mount.h>
#include "pathnames.h"
#include "loopdev.h"
#include "strutils.h"
#include "mountP.h"
/*
* umount2 flags
*/
#ifndef MNT_FORCE
# define MNT_FORCE 0x00000001 /* Attempt to forcibily umount */
#endif
#ifndef MNT_DETACH
# define MNT_DETACH 0x00000002 /* Just detach from the tree */
#endif
#ifndef UMOUNT_NOFOLLOW
# define UMOUNT_NOFOLLOW 0x00000008 /* Don't follow symlink on umount */
#endif
#ifndef UMOUNT_UNUSED
# define UMOUNT_UNUSED 0x80000000 /* Flag guaranteed to be unused */
#endif
/*
* Called by mtab parser to filter out entries, nonzero means that
* entry has to be filter out.
*/
static int mtab_filter(struct libmnt_fs *fs, void *data)
{
if (!fs || !data)
return 0;
if (mnt_fs_streq_target(fs, data))
return 0;
if (mnt_fs_streq_srcpath(fs, data))
return 0;
return 1;
}
static int lookup_umount_fs(struct libmnt_context *cxt)
{
int rc, loopdev = 0;
const char *tgt;
struct libmnt_table *mtab = NULL;
struct libmnt_fs *fs;
struct libmnt_cache *cache = NULL;
char *cn_tgt = NULL;
assert(cxt);
assert(cxt->fs);
DBG(CXT, mnt_debug_h(cxt, "umount: lookup FS"));
tgt = mnt_fs_get_target(cxt->fs);
if (!tgt) {
DBG(CXT, mnt_debug_h(cxt, "umount: undefined target"));
return -EINVAL;
}
/*
* The mtab file maybe huge and on systems with utab we have to merge
* userspace mount options into /proc/self/mountinfo. This all is
* expensive. The mtab filter allows to filter out entries, then
* mtab and utab are very tiny files.
*
* *but*... the filter uses mnt_fs_streq_{target,srcpath} functions
* where LABEL, UUID or symlinks are to canonicalized. It means that
* it's usable only for canonicalized stuff (e.g. kernel mountinfo).
*/
if (!cxt->mtab_writable && *tgt == '/') {
struct stat st;
if (stat(tgt, &st) == 0 && S_ISDIR(st.st_mode)) {
/* we'll canonicalized /proc/self/mountinfo */
cache = mnt_context_get_cache(cxt);
cn_tgt = mnt_resolve_path(tgt, cache);
if (cn_tgt)
mnt_context_set_tabfilter(cxt, mtab_filter, cn_tgt);
}
}
rc = mnt_context_get_mtab(cxt, &mtab);
if (cn_tgt) {
mnt_context_set_tabfilter(cxt, NULL, NULL);
if (!cache)
free(cn_tgt);
}
if (rc) {
DBG(CXT, mnt_debug_h(cxt, "umount: failed to read mtab"));
return rc;
}
try_loopdev:
fs = mnt_table_find_target(mtab, tgt, MNT_ITER_BACKWARD);
if (!fs && mnt_context_is_swapmatch(cxt)) {
/* maybe the option is source rather than target (mountpoint) */
fs = mnt_table_find_source(mtab, tgt, MNT_ITER_BACKWARD);
if (fs) {
struct libmnt_fs *fs1 = mnt_table_find_target(mtab,
mnt_fs_get_target(fs),
MNT_ITER_BACKWARD);
if (!fs1) {
DBG(CXT, mnt_debug_h(cxt, "mtab is broken?!?!"));
return -EINVAL;
}
if (fs != fs1) {
/* Something was stacked over `file' on the
* same mount point. */
DBG(CXT, mnt_debug_h(cxt,
"umount: %s: %s is mounted "
"over it on the same point",
tgt, mnt_fs_get_source(fs1)));
return -EINVAL;
}
}
}
if (!fs && !loopdev) {
/*
* Maybe target is /path/file.img, try to convert to /dev/loopN
*/
struct stat st;
if (stat(tgt, &st) == 0 && S_ISREG(st.st_mode)) {
char *dev = NULL;
int count = loopdev_count_by_backing_file(tgt, &dev);
if (count == 1) {
DBG(CXT, mnt_debug_h(cxt,
"umount: %s --> %s (retry)", tgt, dev));
mnt_fs_set_source(cxt->fs, tgt);
mnt_fs_set_target(cxt->fs, dev);
free(dev);
tgt = mnt_fs_get_target(cxt->fs);
loopdev = 1; /* to avoid endless loop */
goto try_loopdev;
} else if (count > 1)
DBG(CXT, mnt_debug_h(cxt,
"umount: warning: %s is associated "
"with more than one loopdev", tgt));
}
}
if (!fs) {
DBG(CXT, mnt_debug_h(cxt, "umount: cannot find %s in mtab", tgt));
return 0;
}
if (fs != cxt->fs) {
/* copy from mtab to our FS description
*/
mnt_fs_set_source(cxt->fs, NULL);
mnt_fs_set_target(cxt->fs, NULL);
if (!mnt_copy_fs(cxt->fs, fs)) {
DBG(CXT, mnt_debug_h(cxt, "umount: failed to copy FS"));
return -errno;
}
DBG(CXT, mnt_debug_h(cxt, "umount: mtab applied"));
}
cxt->flags |= MNT_FL_TAB_APPLIED;
return rc;
}
/* check if @devname is loopdev and if the device is associated
* with a source from @fstab_fs
*/
static int is_associated_fs(const char *devname, struct libmnt_fs *fs)
{
uintmax_t offset = 0;
const char *src;
char *val, *optstr;
size_t valsz;
int flags = 0;
/* check if it begins with /dev/loop */
if (strncmp(devname, _PATH_DEV_LOOP, sizeof(_PATH_DEV_LOOP) - 1))
return 0;
src = mnt_fs_get_srcpath(fs);
if (!src)
return 0;
/* check for offset option in @fs */
optstr = (char *) mnt_fs_get_user_options(fs);
if (optstr &&
mnt_optstr_get_option(optstr, "offset", &val, &valsz) == 0) {
flags |= LOOPDEV_FL_OFFSET;
if (mnt_parse_offset(val, valsz, &offset) != 0)
return 0;
}
return loopdev_is_used(devname, src, offset, flags);
}
static int prepare_helper_from_options(struct libmnt_context *cxt,
const char *name)
{
char *suffix = NULL;
const char *opts;
size_t valsz;
if (mnt_context_is_nohelpers(cxt))
return 0;
opts = mnt_fs_get_user_options(cxt->fs);
if (!opts)
return 0;
if (mnt_optstr_get_option(opts, name, &suffix, &valsz))
return 0;
suffix = strndup(suffix, valsz);
if (!suffix)
return -ENOMEM;
DBG(CXT, mnt_debug_h(cxt, "umount: umount.%s %s requested", suffix, name));
return mnt_context_prepare_helper(cxt, "umount", suffix);
}
/*
* Note that cxt->fs contains relevant mtab entry!
*/
static int evaluate_permissions(struct libmnt_context *cxt)
{
struct libmnt_table *fstab;
unsigned long u_flags = 0;
const char *tgt, *src, *optstr;
int rc, ok = 0;
struct libmnt_fs *fs;
assert(cxt);
assert(cxt->fs);
assert((cxt->flags & MNT_FL_MOUNTFLAGS_MERGED));
if (!cxt || !cxt->fs)
return -EINVAL;
if (!mnt_context_is_restricted(cxt))
return 0; /* superuser mount */
DBG(CXT, mnt_debug_h(cxt, "umount: evaluating permissions"));
if (!(cxt->flags & MNT_FL_TAB_APPLIED)) {
DBG(CXT, mnt_debug_h(cxt,
"cannot find %s in mtab and you are not root",
mnt_fs_get_target(cxt->fs)));
goto eperm;
}
if (cxt->user_mountflags & MNT_MS_UHELPER) {
/* on uhelper= mount option based helper */
rc = prepare_helper_from_options(cxt, "uhelper");
if (rc)
return rc;
if (cxt->helper)
return 0; /* we'll call /sbin/umount.<uhelper> */
}
/*
* User mounts has to be in /etc/fstab
*/
rc = mnt_context_get_fstab(cxt, &fstab);
if (rc)
return rc;
tgt = mnt_fs_get_target(cxt->fs);
src = mnt_fs_get_source(cxt->fs);
if (mnt_fs_get_bindsrc(cxt->fs)) {
src = mnt_fs_get_bindsrc(cxt->fs);
DBG(CXT, mnt_debug_h(cxt,
"umount: using bind source: %s", src));
}
/* If fstab contains the two lines
* /dev/sda1 /mnt/zip auto user,noauto 0 0
* /dev/sda4 /mnt/zip auto user,noauto 0 0
* then "mount /dev/sda4" followed by "umount /mnt/zip" used to fail.
* So, we must not look for file, but for the pair (dev,file) in fstab.
*/
fs = mnt_table_find_pair(fstab, src, tgt, MNT_ITER_FORWARD);
if (!fs) {
/*
* It's possible that there is /path/file.img in fstab and
* /dev/loop0 in mtab -- then we have to check releation
* between loopdev and the file.
*/
fs = mnt_table_find_target(fstab, tgt, MNT_ITER_FORWARD);
if (fs) {
const char *dev = mnt_fs_get_srcpath(cxt->fs); /* devname from mtab */
if (!dev || !is_associated_fs(dev, fs))
fs = NULL;
}
if (!fs) {
DBG(CXT, mnt_debug_h(cxt,
"umount %s: mtab disagrees with fstab",
tgt));
goto eperm;
}
}
/*
* User mounting and unmounting is allowed only if fstab contains one
* of the options `user', `users' or `owner' or `group'.
*
* The option `users' allows arbitrary users to mount and unmount -
* this may be a security risk.
*
* The options `user', `owner' and `group' only allow unmounting by the
* user that mounted (visible in mtab).
*/
optstr = mnt_fs_get_user_options(fs); /* FSTAB mount options! */
if (!optstr)
goto eperm;
if (mnt_optstr_get_flags(optstr, &u_flags,
mnt_get_builtin_optmap(MNT_USERSPACE_MAP)))
goto eperm;
if (u_flags & MNT_MS_USERS) {
DBG(CXT, mnt_debug_h(cxt,
"umount: promiscuous setting ('users') in fstab"));
return 0;
}
/*
* Check user=<username> setting from mtab if there is user, owner or
* group option in /etc/fstab
*/
if (u_flags & (MNT_MS_USER | MNT_MS_OWNER | MNT_MS_GROUP)) {
char *curr_user = NULL;
char *mtab_user = NULL;
size_t sz;
DBG(CXT, mnt_debug_h(cxt,
"umount: checking user=<username> from mtab"));
curr_user = mnt_get_username(getuid());
if (!curr_user) {
DBG(CXT, mnt_debug_h(cxt, "umount %s: cannot "
"convert %d to username", tgt, getuid()));
goto eperm;
}
/* get options from mtab */
optstr = mnt_fs_get_user_options(cxt->fs);
if (optstr && !mnt_optstr_get_option(optstr,
"user", &mtab_user, &sz) && sz)
ok = !strncmp(curr_user, mtab_user, sz);
}
if (ok) {
DBG(CXT, mnt_debug_h(cxt, "umount %s is allowed", tgt));
return 0;
}
eperm:
DBG(CXT, mnt_debug_h(cxt, "umount is not allowed for you"));
return -EPERM;
}
static int exec_helper(struct libmnt_context *cxt)
{
int rc;
assert(cxt);
assert(cxt->fs);
assert(cxt->helper);
assert((cxt->flags & MNT_FL_MOUNTFLAGS_MERGED));
assert(cxt->helper_exec_status == 1);
DBG_FLUSH;
switch (fork()) {
case 0:
{
const char *args[10], *type;
int i = 0;
if (setgid(getgid()) < 0)
exit(EXIT_FAILURE);
if (setuid(getuid()) < 0)
exit(EXIT_FAILURE);
type = mnt_fs_get_fstype(cxt->fs);
args[i++] = cxt->helper; /* 1 */
args[i++] = mnt_fs_get_target(cxt->fs); /* 2 */
if (mnt_context_is_nomtab(cxt))
args[i++] = "-n"; /* 3 */
if (mnt_context_is_lazy(cxt))
args[i++] = "-l"; /* 4 */
if (mnt_context_is_force(cxt))
args[i++] = "-f"; /* 5 */
if (mnt_context_is_verbose(cxt))
args[i++] = "-v"; /* 6 */
if (mnt_context_is_rdonly_umount(cxt))
args[i++] = "-r"; /* 7 */
if (type && !endswith(cxt->helper, type)) {
args[i++] = "-t"; /* 8 */
args[i++] = (char *) type; /* 9 */
}
args[i] = NULL; /* 10 */
#ifdef CONFIG_LIBMOUNT_DEBUG
for (i = 0; args[i]; i++)
DBG(CXT, mnt_debug_h(cxt, "argv[%d] = \"%s\"",
i, args[i]));
#endif
DBG_FLUSH;
execv(cxt->helper, (char * const *) args);
exit(EXIT_FAILURE);
}
default:
{
int st;
wait(&st);
cxt->helper_status = WIFEXITED(st) ? WEXITSTATUS(st) : -1;
DBG(CXT, mnt_debug_h(cxt, "%s executed [status=%d]",
cxt->helper, cxt->helper_status));
cxt->helper_exec_status = rc = 0;
break;
}
case -1:
cxt->helper_exec_status = rc = -errno;
DBG(CXT, mnt_debug_h(cxt, "fork() failed"));
break;
}
return rc;
}
/*
* mnt_context_helper_setopt() backend.
*
* This function applies umount.type command line option (for example parsed
* by getopt() or getopt_long()) to @cxt. All unknown options are ignored and
* then 1 is returned.
*
* Returns: negative number on error, 1 if @c is unknown option, 0 on success.
*/
int mnt_context_umount_setopt(struct libmnt_context *cxt, int c, char *arg)
{
int rc = -EINVAL;
assert(cxt);
assert(cxt->action == MNT_ACT_UMOUNT);
switch(c) {
case 'n':
rc = mnt_context_disable_mtab(cxt, TRUE);
break;
case 'l':
rc = mnt_context_enable_lazy(cxt, TRUE);
break;
case 'f':
rc = mnt_context_enable_force(cxt, TRUE);
break;
case 'v':
rc = mnt_context_enable_verbose(cxt, TRUE);
break;
case 'r':
rc = mnt_context_enable_rdonly_umount(cxt, TRUE);
break;
case 't':
if (arg)
rc = mnt_context_set_fstype(cxt, arg);
break;
default:
return 1;
break;
}
return rc;
}
/* Check whether the kernel supports UMOUNT_NOFOLLOW flag */
static int umount_nofollow_support(void)
{
int res = umount2("", UMOUNT_UNUSED);
if (res != -1 || errno != EINVAL)
return 0;
res = umount2("", UMOUNT_NOFOLLOW);
if (res != -1 || errno != ENOENT)
return 0;
return 1;
}
static int do_umount(struct libmnt_context *cxt)
{
int rc = 0, flags = 0;
const char *src, *target;
char *tgtbuf = NULL;
assert(cxt);
assert(cxt->fs);
assert((cxt->flags & MNT_FL_MOUNTFLAGS_MERGED));
assert(cxt->syscall_status == 1);
if (cxt->helper)
return exec_helper(cxt);
src = mnt_fs_get_srcpath(cxt->fs);
target = mnt_fs_get_target(cxt->fs);
if (!target)
return -EINVAL;
DBG(CXT, mnt_debug_h(cxt, "do umount"));
if (cxt->restricted && !mnt_context_is_fake(cxt)) {
/*
* extra paranoia for non-root users
* -- chdir to the parent of the mountpoint and use NOFOLLOW
* flag to avoid races and symlink attacks.
*/
if (umount_nofollow_support())
flags |= UMOUNT_NOFOLLOW;
rc = mnt_chdir_to_parent(target, &tgtbuf);
if (rc)
return rc;
target = tgtbuf;
}
if (mnt_context_is_lazy(cxt))
flags |= MNT_DETACH;
else if (mnt_context_is_force(cxt))
flags |= MNT_FORCE;
DBG(CXT, mnt_debug_h(cxt, "umount(2) [target='%s', flags=0x%08x]%s",
target, flags,
mnt_context_is_fake(cxt) ? " (FAKE)" : ""));
if (mnt_context_is_fake(cxt))
rc = 0;
else {
rc = flags ? umount2(target, flags) : umount(target);
if (rc < 0)
cxt->syscall_status = -errno;
free(tgtbuf);
}
/*
* try remount read-only
*/
if (rc < 0
&& cxt->syscall_status == -EBUSY
&& mnt_context_is_rdonly_umount(cxt)
&& src) {
mnt_context_set_mflags(cxt, (cxt->mountflags |
MS_REMOUNT | MS_RDONLY));
mnt_context_enable_loopdel(cxt, FALSE);
DBG(CXT, mnt_debug_h(cxt,
"umount(2) failed [errno=%d] -- trying to remount read-only",
-cxt->syscall_status));
rc = mount(src, mnt_fs_get_target(cxt->fs), NULL,
MS_MGC_VAL | MS_REMOUNT | MS_RDONLY, NULL);
if (rc < 0) {
cxt->syscall_status = -errno;
DBG(CXT, mnt_debug_h(cxt,
"read-only re-mount(2) failed [errno=%d]",
-cxt->syscall_status));
return -cxt->syscall_status;
}
cxt->syscall_status = 0;
DBG(CXT, mnt_debug_h(cxt, "read-only re-mount(2) success"));
return 0;
}
if (rc < 0) {
DBG(CXT, mnt_debug_h(cxt, "umount(2) failed [errno=%d]",
-cxt->syscall_status));
return -cxt->syscall_status;
}
cxt->syscall_status = 0;
DBG(CXT, mnt_debug_h(cxt, "umount(2) success"));
return 0;
}
/**
* mnt_context_prepare_umount:
* @cxt: mount context
*
* Prepare context for umounting, unnecessary for mnt_context_umount().
*
* Returns: 0 on success, and negative number in case of error.
*/
int mnt_context_prepare_umount(struct libmnt_context *cxt)
{
int rc;
assert(cxt);
assert(cxt->fs);
assert(cxt->helper_exec_status == 1);
assert(cxt->syscall_status == 1);
if (!cxt || !cxt->fs || mnt_fs_is_swaparea(cxt->fs))
return -EINVAL;
if (!mnt_context_get_source(cxt) && !mnt_context_get_target(cxt))
return -EINVAL;
if (cxt->flags & MNT_FL_PREPARED)
return 0;
free(cxt->helper); /* be paranoid */
cxt->helper = NULL;
cxt->action = MNT_ACT_UMOUNT;
rc = lookup_umount_fs(cxt);
if (!rc)
rc = mnt_context_merge_mflags(cxt);
if (!rc)
rc = evaluate_permissions(cxt);
if (!rc && !cxt->helper) {
if (cxt->user_mountflags & MNT_MS_HELPER)
/* on helper= mount option based helper */
rc = prepare_helper_from_options(cxt, "helper");
if (!rc && !cxt->helper)
/* on fstype based helper */
rc = mnt_context_prepare_helper(cxt, "umount", NULL);
}
if (!rc && (cxt->user_mountflags & MNT_MS_LOOP))
/* loop option explicitly specified in mtab, detach this loop */
mnt_context_enable_loopdel(cxt, TRUE);
if (!rc && mnt_context_is_loopdel(cxt) && cxt->fs) {
const char *src = mnt_fs_get_srcpath(cxt->fs);
if (src && (!is_loopdev(src) || loopdev_is_autoclear(src)))
mnt_context_enable_loopdel(cxt, FALSE);
}
if (rc) {
DBG(CXT, mnt_debug_h(cxt, "umount: preparing failed"));
return rc;
}
cxt->flags |= MNT_FL_PREPARED;
return rc;
}
/**
* mnt_context_do_umount:
* @cxt: mount context
*
* Umount filesystem by umount(2) or fork()+exec(/sbin/umount.type).
* Unnecessary for mnt_context_umount().
*
* See also mnt_context_disable_helpers().
*
* WARNING: non-zero return code does not mean that umount(2) syscall or
* umount.type helper wasn't successfully called.
*
* Check mnt_context_get_status() after error!
*
* Returns: 0 on success;
* >0 in case of umount(2) error (returns syscall errno),
* <0 in case of other errors.
*/
int mnt_context_do_umount(struct libmnt_context *cxt)
{
int rc;
assert(cxt);
assert(cxt->fs);
assert(cxt->helper_exec_status == 1);
assert(cxt->syscall_status == 1);
assert((cxt->flags & MNT_FL_PREPARED));
assert((cxt->action == MNT_ACT_UMOUNT));
assert((cxt->flags & MNT_FL_MOUNTFLAGS_MERGED));
rc = do_umount(cxt);
if (rc)
return rc;
if (mnt_context_get_status(cxt) && !mnt_context_is_fake(cxt)) {
/*
* Umounted, do some post-umount operations
* - remove loopdev
* - refresh in-memory mtab stuff if remount rather than
* umount has been performed
*/
if (mnt_context_is_loopdel(cxt)
&& !(cxt->mountflags & MS_REMOUNT))
rc = mnt_context_delete_loopdev(cxt);
if (!mnt_context_is_nomtab(cxt)
&& mnt_context_get_status(cxt)
&& !cxt->helper
&& mnt_context_is_rdonly_umount(cxt)
&& (cxt->mountflags & MS_REMOUNT)) {
/* use "remount" instead of "umount" in /etc/mtab */
if (!rc && cxt->update && cxt->mtab_writable)
rc = mnt_update_set_fs(cxt->update,
cxt->mountflags, NULL, cxt->fs);
}
}
return rc;
}
/**
* mnt_context_finalize_umount:
* @cxt: context
*
* Mtab update, etc. Unnecessary for mnt_context_umount(), but should be called
* after mnt_context_do_umount(). See also mnt_context_set_syscall_status().
*
* Returns: negative number on error, 0 on success.
*/
int mnt_context_finalize_umount(struct libmnt_context *cxt)
{
int rc;
assert(cxt);
assert(cxt->fs);
assert((cxt->flags & MNT_FL_PREPARED));
assert((cxt->flags & MNT_FL_MOUNTFLAGS_MERGED));
rc = mnt_context_prepare_update(cxt);
if (!rc)
rc = mnt_context_update_tabs(cxt);;
return rc;
}
/**
* mnt_context_umount:
* @cxt: umount context
*
* High-level, umounts filesystem by umount(2) or fork()+exec(/sbin/umount.type).
*
* This is similar to:
*
* mnt_context_prepare_umount(cxt);
* mnt_context_do_umount(cxt);
* mnt_context_finalize_umount(cxt);
*
* See also mnt_context_disable_helpers().
*
* WARNING: non-zero return code does not mean that umount(2) syscall or
* umount.type helper wasn't successfully called.
*
* Check mnt_context_get_status() after error!
*
* Returns: 0 on success;
* >0 in case of umount(2) error (returns syscall errno),
* <0 in case of other errors.
*/
int mnt_context_umount(struct libmnt_context *cxt)
{
int rc;
assert(cxt);
assert(cxt->fs);
assert(cxt->helper_exec_status == 1);
assert(cxt->syscall_status == 1);
DBG(CXT, mnt_debug_h(cxt, "umount: %s", mnt_context_get_target(cxt)));
rc = mnt_context_prepare_umount(cxt);
if (!rc)
rc = mnt_context_prepare_update(cxt);
if (!rc)
rc = mnt_context_do_umount(cxt);
if (!rc)
rc = mnt_context_update_tabs(cxt);
return rc;
}
/**
* mnt_context_next_umount:
* @cxt: context
* @itr: iterator
* @fs: returns the current filesystem
* @mntrc: returns the return code from mnt_context_umount()
* @ignored: returns 1 for not matching
*
* This function tries to umount the next filesystem from mtab (as returned by
* mnt_context_get_mtab()).
*
* You can filter out filesystems by:
* mnt_context_set_options_pattern() to simulate umount -a -O pattern
* mnt_context_set_fstype_pattern() to simulate umount -a -t pattern
*
* If the filesystem is not mounted or does not match defined criteria,
* then the function mnt_context_next_umount() returns zero, but the @ignored is
* non-zero. Note that the root filesystem is always ignored.
*
* If umount(2) syscall or umount.type helper failed, then the
* mnt_context_next_umount() function returns zero, but the @mntrc is non-zero.
* Use also mnt_context_get_status() to check if the filesystem was
* successfully umounted.
*
* Returns: 0 on success,
* <0 in case of error (!= umount(2) errors)
* 1 at the end of the list.
*/
int mnt_context_next_umount(struct libmnt_context *cxt,
struct libmnt_iter *itr,
struct libmnt_fs **fs,
int *mntrc,
int *ignored)
{
struct libmnt_table *mtab;
const char *tgt;
int rc;
if (ignored)
*ignored = 0;
if (mntrc)
*mntrc = 0;
if (!cxt || !fs || !itr)
return -EINVAL;
rc = mnt_context_get_mtab(cxt, &mtab);
cxt->mtab = NULL; /* do not reset mtab */
mnt_reset_context(cxt);
cxt->mtab = mtab;
if (rc)
return rc;
do {
rc = mnt_table_next_fs(mtab, itr, fs);
if (rc != 0)
return rc; /* no more filesystems (or error) */
tgt = mnt_fs_get_target(*fs);
} while (!tgt);
DBG(CXT, mnt_debug_h(cxt, "next-umount: trying %s", tgt));
/* ignore root filesystem */
if ((tgt && (strcmp(tgt, "/") == 0 || strcmp(tgt, "root") == 0)) ||
/* ignore filesystems not match with options patterns */
(cxt->fstype_pattern && !mnt_fs_match_fstype(*fs,
cxt->fstype_pattern)) ||
/* ignore filesystems not match with type patterns */
(cxt->optstr_pattern && !mnt_fs_match_options(*fs,
cxt->optstr_pattern))) {
if (ignored)
*ignored = 1;
DBG(CXT, mnt_debug_h(cxt, "next-umount: not-match "
"[fstype: %s, t-pattern: %s, options: %s, O-pattern: %s]",
mnt_fs_get_fstype(*fs),
cxt->fstype_pattern,
mnt_fs_get_options(*fs),
cxt->optstr_pattern));
return 0;
}
rc = mnt_context_set_fs(cxt, *fs);
if (rc)
return rc;
rc = mnt_context_umount(cxt);
if (mntrc)
*mntrc = rc;
return 0;
}