If -oloop is used and the loop device is reused, the loop device is detached
after umount. It is incorrect as it could break the another task using the loop
device.
This is caused by mnt_context_enable_loopdel(,TRUE) that is called from
mnt_context_prepare_umount() whenever "loop" option is used, independently on
AUTOCLEAR flag.
Remove the "loop" option for reused devices to prevent detaching of reused loop
device.
Signed-off-by: Stanislav Brabec <sbrabec@suse.cz>
If mount option "loop" is used with an argument, it should be respected. Commit
8efad715 introduced a regression. Even with an argument, overlaying loop device
is searched and argument is ignored. It could have unexpected side effects.
If argument is set, never allocate a new loop device.
How to reproduce:
mkdir -p cdrom
mkisofs -o cdrom.iso cdrom/ 2>/dev/null
losetup /dev/loop0 cdrom.iso
strace mount -t auto -o ro,loop=/dev/loop1 cdrom.iso /mnt 2>&1 | grep ^mount
cat /proc/self/mountinfo | grep /mnt
umount /mnt
losetup -d /dev/loop0
mount("/dev/loop0", "/mnt", "iso9660", MS_MGC_VAL|MS_RDONLY, NULL) = 0
327 60 7:0 / /mnt ro,relatime shared:241 - iso9660 /dev/loop0 ro
losetup: /dev/loop0: detach failed: No such device or address
Signed-off-by: Stanislav Brabec <sbrabec@suse.cz>
Commit f9906424 introduced a check that should prevent different information in
mtab and /proc/mounts. The check can require significant amount of time, and for
systems without mtab support it has no sense.
Execute this code only on systems with mtab.
When a systems with large number of nodes (thousands) mount the filesystems
simultaneously, the time required for serialization causes the utimensat() to
take a large amount of time (tens of minutes) when a large number of nodes are
simultaneously updating the timestamp.
Signed-off-by: Stanislav Brabec <sbrabec@suse.cz>
Let's use optstr.c functions to parse pattern and options strings.
It's more robust that the old original mount(8) code and it supports
quotes in the options strings.
Signed-off-by: Karel Zak <kzak@redhat.com>
The original --target implementation (< v2.27) has been based on
stat(), so it was usable for valid paths only.
The new implementation is based on search in the mountinfo file, so it
works for arbitrary crazy path. This is not backwardly compatible and
if the path does not exist then it still returns at least root
directory mount entry.
This patch forces mnt_table_find_mountpoint() to check if the path is
valid before we search in the mountinfo file.
Signed-off-by: Karel Zak <kzak@redhat.com>
Let's hope this is last change necessary to cleanup x-* usage:
x-* persistent option, stored in utab, available for umount, etc.
X-* fstab comment only
mount(8) supports x-mount.mkdir= as well as newly recommended X-mount.mkdir=
Advantages:
* less invasive
* does not require exception for x-systemd
* does not require rename x-initrd to X-initrd
The systemd and dracut users will get the new (=fixed) functionality without a
change in fstab configuration. This is the primary goal.
Disadvantages:
* not 100% compatible libmount behavior, x-* options have not been
previously stored in utab. The API is the same, options will be still
available, but on x-* libmount will write to /run/mount/utab. For now
it seems only systemd uses x-*, and they like this behavior, so...
Addresses: https://github.com/systemd/systemd/pull/4515
Signed-off-by: Karel Zak <kzak@redhat.com>
Don't know why this was added in d78df0ac but it can't be right that
libmount/python removes these files in the toplevel builddir. Moreover
I've never seen such *.img files appearing during build at all.
Signed-off-by: Ruediger Meier <ruediger.meier@ga-group.nl>
The previous patch introduces X-* options namespace for options
that have to be maintained in user space.
Unfortunately, systemd users already use mount options that are
necessary by umount or another operations. The conclusion from
discussion with systemd guys is to store all the systemd options
in userspace.
It seems better to add one line exception to libmount than force all
fstab users to rename x-systemd to X-systemd.
Addresses: https://github.com/systemd/systemd/pull/3904
Signed-off-by: Karel Zak <kzak@redhat.com>
x-* are fstab only and not stored in userspace (utab). In some cases
it's not optional solution because the option is also necessary for
umount or another operations. The X-* is exactly the same as x-*, but
stored to utab (or mtab on old systems).
It's usually bad idea to store mount options in userspace, but it's
better to provide any solution that force users to bypass mount(8)
(and friends) and implement 3rd-party incompatible solutions.
Signed-off-by: Karel Zak <kzak@redhat.com>
If you call mount(8) as root, then we need to append inverting options
(if specified by fstab) for "user" and "users" to /sbin/mount.<type>
command line, because for UID=0 mount.nfs follows command line rather
than the fstab setting.
This has been originally implemented by commit
a4c0cc75ff for the old mount(8). The
same feature is supported by libmount, unfortunately for "user" only.
We need the same also for "users" to be backwardly compatible.
Addresses: https://github.com/karelzak/util-linux/issues/368
Signed-off-by: Karel Zak <kzak@redhat.com>
when mounting a cifs share, the src is actually an UNC path which can in
in several forms:
simple: //host/share, //host/share/
including subpath: //host/share/sub/path
to check if the cifs fs is mounted we have to extract the subpath and
compare *that* to the root.
Signed-off-by: Aurelien Aptel <aaptel@suse.com>
Recent mount (since the switch to libmount in v2.22) drops the '=' in
mount options that are set to an empty value. For example, the command
line below will be affected:
# mount -o rw,myopt='' -t tmpfs tmpfs /mnt/tmp
Fix that by preserving an empty string in the options passed to the
mount(2) syscall when they are present on the command line.
Add test cases to ensure empty string handling is working as expected
and in order to prevent regressions in the future.
Also tested manually by stracing mount commands (on a kernel which
accepts a special extra option, for testing purposes.)
Before this commit:
# strace -e mount ./mount -t tmpfs -o rw,myopt='' tmpfs /mnt/tmp
mount("tmpfs", "/mnt/tmp", "tmpfs", MS_MGC_VAL, "myarg") = -1 EINVAL (Invalid argument)
After this commit:
# strace -e mount ./mount -t tmpfs -o rw,myopt='' tmpfs /mnt/tmp
mount("tmpfs", "/mnt/tmp", "tmpfs", MS_MGC_VAL, "myopt=") = 0
All test cases pass, including newly added test cases. Also checked
them with valgrind using:
$ tests/run.sh --memcheck libmount/optstr
Fixes#332.
Signed-off-by: Filipe Brandenburger <filbranden@google.com>
///aaa/bbb and /aaa/bbb/ are the same paths. This is important
especially with NFS where number of slashes are not the same in
the /proc/self/mountinfo and fstab or utab. The regular URI is
euler://tmp
but /proc contains
euler:/tmp
Reported-by: Ales Novak <alnovak@suse.cz>
Signed-off-by: Karel Zak <kzak@redhat.com>
The current code scans loopdevs to detect already used loop device and
another scan to detect overlap.
Let's use one scan only, for this purpose loopcxt_find_overlap() has
been modified to return info (rc==2) about full size and offset match.
Signed-off-by: Karel Zak <kzak@redhat.com>
Add a safety check to mnt_context_setup_loopdev(). Only a loop device with equal
offset and sizelimit will be reused. If any overlapping loop device exists,
MNT_ERR_LOOPOVERLAP is returned.
Signed-off-by: Stanislav Brabec <sbrabec@suse.cz>
Fully safe checks of loop device need to check sizelimit. To prevent need of two
nearly equal functions, introduce sizelimit parameter to several internal
functions:
loopdev_is_used()
loopdev_find_by_backing_file()
loopcxt_is_used()
loopcxt_find_by_backing_file()
If sizelimit is zero, fall back to the old behavior (ignoring of sizelimit).
Signed-off-by: Stanislav Brabec <sbrabec@suse.cz>
This error code is intended for situations where overlapping loop device exists
and cannot be reused.
Signed-off-by: Stanislav Brabec <sbrabec@suse.cz>
Fix various typos in error messages, warnings, debug strings,
comments and names of static functions.
Signed-off-by: Sebastian Rasmussen <sebras@gmail.com>
For petty long time we have strdup_to_struct_member() macro to avoid
duplicate code when strdup() strings in setter functions. Let's use it
for libmount.
Signed-off-by: Karel Zak <kzak@redhat.com>
According to the Al Viro[1], kernel has no way to detect that a single file is
used by multiple loop devices, and multiple mounts of the same file using
different loop devices will result in a data corruption. Exactly this now
happens, if multiple btrfs sub-volumes in one file are mounted with "-oloop".
Make use of multiple -oloop mounting the same file safe: Do a loop devices
lookup, and if a loop device is already initialized, use it.
Hopefully it is possible, as "losetup -d" will return OK, even if the device
itself is in use, and is not released.
Problems:
There is a risk of race condition between the lookup and real mount.
Once loop device is initialized read-only, kernel offers no way to turn it to
read-write. It has to fail.
References:
https://lkml.org/lkml/2016/2/26/897
Signed-off-by: Stanislav Brabec <sbrabec@suse.cz>
First parse options, then initialize context.
No change in function.
The change is needed for loop device reuse.
Signed-off-by: Stanislav Brabec <sbrabec@suse.cz>
The file mtab is evil and already unused by mainstream distributions.
Now libmount is able to detect mtab->/proc/mounts and use
/proc/self/mountinfo if necessary. This heuristic seems overkill in
many cases. It's also dangerous on systems where mountinfo is strongly
required (systemd based distros).
This patch #ifdefs mtab code and forces libmount to always use
/proc/self/mountinfo.
The new configure option --enable-libmount-support-mtab is necessary
to enable old behavior to support mtab.
Signed-off-by: Karel Zak <kzak@redhat.com>
The path canonicalization is expensive and in many cases unwanted due
to problems with readlink() on unreachable NFS and automounters.
This patch add a possibility to search also by $(CWD)/<path> if the
<path> is relative to reduce number of situation when we convert the
path to the canonical absolute path.
The common use-case:
# cd /some/long/path
# umount ./mountpoint
old version:
15543: libmount: TAB: [0x560a99a54230]: lookup TARGET: './test'
15543: libmount: CACHE: [0x560a99a54290]: canonicalize path ./test
15543: libmount: CACHE: [0x560a99a54290]: add entry [ 1] (path): /mnt/test: ./test
15543: libmount: TAB: [0x560a99a54230]: lookup canonical TARGET: '/mnt/test'
15543: libmount: CXT: [0x560a99a54050]: umount fs: /mnt/test
new version:
15597: libmount: TAB: [0xabf230]: lookup TARGET: './test'
15597: libmount: TAB: [0xabf230]: lookup absolute TARGET: '/mnt/test'
15597: libmount: CXT: [0xabf050]: umount fs: /mnt/test
Signed-off-by: Karel Zak <kzak@redhat.com>
The function mnt_table_get_fs_root() should be robust enough to accept
NULL as mountinfo -- the right behaviour is to default to '/'.
The set_fs_root() (tab_update.c) has to understand when mountinfo is
necessary (for bind mounts and btrfs).
Reported-by: Stanislav Brabec <sbrabec@suse.cz>
Signed-off-by: Karel Zak <kzak@redhat.com>
Currently the code supports /dev/name or PARTUUID= only. We also
need to support 'maj:min' and 'hexhex' notations.
Reported-by: George Spelvin <linux@horizon.com>
Signed-off-by: Karel Zak <kzak@redhat.com>
clang warning:
libmount/src/tab.c:1833:6: warning: variable 'rc' is used uninitialized whenever
'if' condition is true [-Wsometimes-uninitialized]
if (!mpc)
^~~~
icc printf warnings:
libmount/src/monitor.c(348): warning #2279: printf/scanf format not a string literal and no format arguments
DBG(MONITOR, ul_debugobj(mn, status == 1 ? " success" : " nothing"));
^
login-utils/vipw.c(348): warning #2279: printf/scanf format not a string literal and no format arguments
: _("You are using shadow passwords on this system.\n"));
^
icc enum warnings:
disk-utils/fdisk-menu.c(150): warning #188: enumerated type mixed with another type
.exclude = FDISK_DISKLABEL_GPT | FDISK_DISKLABEL_BSD,
^
libsmartcols/src/table_print.c(750): warning #188: enumerated type mixed with another type
&width, align,
^
Signed-off-by: Ruediger Meier <ruediger.meier@ga-group.nl>
Karel Zak
Stanislav Brabec
Sébastien Helleu
Ruediger Meier
Aurelien Aptel
Filipe Brandenburger
Sami Kerola
Sebastian Rasmussen
Ruediger Meier