Coverity caught unsafe use of `strcpy()` in `ztest_dmu_objset_own()`,
`nfs_init_tmpfile()` and `dump_snapshot()`. It also caught an unsafe use
of `strlcat()` in `nfs_init_tmpfile()`.
Inspired by this, I did an audit of every single usage of `strcpy()` and
`strcat()` in the code. If I could not prove that the usage was safe, I
changed the code to use either `strlcpy()` or `strlcat()`, depending on
which function was originally used. In some cases, `snprintf()` was used
to replace multiple uses of `strcat` because it was cleaner.
Whenever I changed a function, I preferred to use `sizeof(dst)` when the
compiler is able to provide the string size via that. When it could not
because the string was passed by a caller, I checked the entire call
tree of the function to find out how big the buffer was and hard coded
it. Hardcoding is less than ideal, but it is safe unless someone shrinks
the buffer sizes being passed.
Additionally, Coverity reported three more string related issues:
* It caught a case where we do an overlapping memory copy in a call to
`snprintf()`. We fix that via `kmem_strdup()` and `kmem_strfree()`.
* It caught `sizeof (buf)` being used instead of `buflen` in
`zdb_nicenum()`'s call to `zfs_nicenum()`, which is passed to
`snprintf()`. We change that to pass `buflen`.
* It caught a theoretical unterminated string passed to `strcmp()`.
This one is likely a false positive, but we have the information
needed to do this more safely, so we change this to silence the false
positive not just in coverity, but potentially other static analysis
tools too. We switch to `strncmp()`.
* There was a false positive in tests/zfs-tests/cmd/dir_rd_update.c. We
suppress it by switching to `snprintf()` since other static analysis
tools might complain about it too. Interestingly, there is a possible
real bug there too, since it assumes that the passed directory path
ends with '/'. We add a '/' to fix that potential bug.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Richard Yao <richard.yao@alumni.stonybrook.edu>
Closes#13913
Makes the case sensitivity setting visible on Linux in /proc/mounts.
Reviewed-by: Ryan Moeller <ryan@iXsystems.com>
Reviewed-by: Alexander Motin <mav@FreeBSD.org>
Signed-off-by: Ameer Hamza <ahamza@ixsystems.com>
Closes#13607
zfs_userns opens a file descriptor for the kernel to look up a
namespace, but does not close it.
Close the fd when we're done with it.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Allan Jude <allan@klarasystems.com>
Signed-off-by: Ryan Moeller <freqlabs@FreeBSD.org>
Closes#13554
This allows ZFS datasets to be delegated to a user/mount namespace
Within that namespace, only the delegated datasets are visible
Works very similarly to Zones/Jailes on other ZFS OSes
As a user:
```
$ unshare -Um
$ zfs list
no datasets available
$ echo $$
1234
```
As root:
```
# zfs list
NAME ZONED MOUNTPOINT
containers off /containers
containers/host off /containers/host
containers/host/child off /containers/host/child
containers/host/child/gchild off /containers/host/child/gchild
containers/unpriv on /unpriv
containers/unpriv/child on /unpriv/child
containers/unpriv/child/gchild on /unpriv/child/gchild
# zfs zone /proc/1234/ns/user containers/unpriv
```
Back to the user namespace:
```
$ zfs list
NAME USED AVAIL REFER MOUNTPOINT
containers 129M 47.8G 24K /containers
containers/unpriv 128M 47.8G 24K /unpriv
containers/unpriv/child 128M 47.8G 128M /unpriv/child
```
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Will Andrews <will.andrews@klarasystems.com>
Signed-off-by: Allan Jude <allan@klarasystems.com>
Signed-off-by: Mateusz Piotrowski <mateusz.piotrowski@klarasystems.com>
Co-authored-by: Allan Jude <allan@klarasystems.com>
Co-authored-by: Mateusz Piotrowski <mateusz.piotrowski@klarasystems.com>
Sponsored-by: Buddy <https://buddy.works>
Closes#12263
Every errbuf array in libzfs is 1024 chars.
Define ERRBUFLEN in a shared header, and use it.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Ryan Moeller <freqlabs@FreeBSD.org>
Closes#13539
This also expands the zfs version output from 127 characters to However
Many Are Actually Set
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Ahelenia Ziemiańska <nabijaczleweli@nabijaczleweli.xyz>
Closes#13330
The short-path is now one access() call,
we always modprobe zfs (ZFS_MODULE_LOADING which doesn't use the libzfs
boolean parsing is gone),
and we use a simple inotify IN_CREATE loop with a timerfd timeout
rather than 10ms kernel-style polling
There's one substantial difference: ZFS_MODULE_TIMEOUT=-1
now means "never give up", rather than "wait 10 minutes"
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Ahelenia Ziemiańska <nabijaczleweli@nabijaczleweli.xyz>
Closes#13330
Improves readability. No functional change intended.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Ryan Moeller <ryan@iXsystems.com>
Closes#13197
Notably, this also means that the pipe is expanded before each
dataset is received, so updates to /p/s/f/pipe-max-size are reflected
for each new dataset
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Rich Ercolani <rincebrain@gmail.com>
Reviewed-by: Paul Dagnelie <pcd@delphix.com>
Signed-off-by: Ahelenia Ziemiańska <nabijaczleweli@nabijaczleweli.xyz>
Closes#13133
They're later |=d with constants, but never reset
Caught by valgrind while investigating
https://github.com/openzfs/zfs/pull/12928#issuecomment-1007496550
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Ahelenia Ziemiańska <nabijaczleweli@nabijaczleweli.xyz>
Closes#12954
Add function zfs_destroy_snaps_nvl_os() call. The main issue is that
macOS needs to unmount any mounted snapshots before they can be
destroyed. Other platforms can handle this in the kernel, but sending
a storm of zed events to unmount seems undesirable when we can do it
in userland to start with.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: John Kennedy <john.kennedy@delphix.com>
Signed-off-by: Jorgen Lundman <lundman@lundman.net>
Co-authored-by: ilovezfs <ilovezfs@icloud.com>
Closes#12550
zpool_disable_datasets_os():
macOS needs to do a bunch of work to kick everything off zvols.
zfs_unmount_os():
This allows us to unmount any zvols that may be mounted. Like with
zfs destroy foo/vol
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: John Kennedy <john.kennedy@delphix.com>
Signed-off-by: Jorgen Lundman <lundman@lundman.net>
Closes#12436
The same change has already been done for domount(). On macOS platform
we need to have access to zhp to handle devdisks and snapshots.
Also, symmetry is pleasing.
In addition, the code in zpool_disable_datasets which sorts the
mountpoints did not sort the related handle, which meant that the
mountpoint, and the handle that it is paired with, was lost.
You'd get a random handle with the mountpoint.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: John Kennedy <john.kennedy@delphix.com>
Signed-off-by: Jorgen Lundman <lundman@lundman.net>
Closes#12296
As found by
git grep -E '(open|setmntent|pipe2?)\(' |
grep -vE '((zfs|zpool)_|fd|dl|lzc_re|pidfile_|g_)open\('
FreeBSD's pidfile_open() says nothing about the flags of the files it
opens, but we can't do anything about it anyway; the implementation does
open all files with O_CLOEXEC
Consider this output with zpool.d/media appended with
"pid=$$; (ls -l /proc/$pid/fd > /dev/tty)":
$ /sbin/zpool iostat -vc media
lrwx------ 0 -> /dev/pts/0
l-wx------ 1 -> 'pipe:[3278500]'
l-wx------ 2 -> /dev/null
lrwx------ 3 -> /dev/zfs
lr-x------ 4 -> /proc/31895/mounts
lrwx------ 5 -> /dev/zfs
lr-x------ 10 -> /usr/lib/zfs-linux/zpool.d/media
vs
$ ./zpool iostat -vc vendor,upath,iostat,media
lrwx------ 0 -> /dev/pts/0
l-wx------ 1 -> 'pipe:[3279887]'
l-wx------ 2 -> /dev/null
lr-x------ 10 -> /usr/lib/zfs-linux/zpool.d/media
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Ahelenia Ziemiańska <nabijaczleweli@nabijaczleweli.xyz>
Closes#11866
Added errno mappings to unmount_one() in libzfs. Changed do_unmount()
implementation to return errno errors directly like is done for
do_mount() and others.
Reviewed-by: Mark Maybee <mark.maybee@delphix.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Don Brady <don.brady@delphix.com>
Closes#11681
When expanding a device zfs needs to rescan the partition table to
get the correct size. This can only happen when we're in the kernel
and requires the device to be closed. As part of the rescan, udev is
notified and the device links are removed and recreated. This leave a
window where the vdev code may try to reopen the device before udev
has recreated the link. If that happens, then the pool may end up in
a suspended state.
To correct this, we leverage the BLKPG_RESIZE_PARTITION ioctl which
allows the partition information to be modified even while it's in use.
This ioctl also does not remove the device link associated with the zfs
data partition so it eliminates the race condition that can occur in
the kernel.
Reviewed-by: Pavel Zakharov <pavel.zakharov@delphix.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: George Wilson <gwilson@delphix.com>
Closes#10897
== Motivation and Context
The current implementation of 'sharenfs' and 'sharesmb' relies on
the use of the sharetab file. The use of this file is os-specific
and not required by linux or freebsd. Currently the code must
maintain updates to this file which adds complexity and presents
a significant performance impact when sharing many datasets. In
addition, concurrently running 'zfs sharenfs' command results in
missing entries in the sharetab file leading to unexpected failures.
== Description
This change removes the sharetab logic from the linux and freebsd
implementation of 'sharenfs' and 'sharesmb'. It still preserves an
os-specific library which contains the logic required for sharing
NFS or SMB. The following entry points exist in the vastly simplified
libshare library:
- sa_enable_share -- shares a dataset but may not commit the change
- sa_disable_share -- unshares a dataset but may not commit the change
- sa_is_shared -- determine if a dataset is shared
- sa_commit_share -- notify NFS/SMB subsystem to commit the shares
- sa_validate_shareopts -- determine if sharing options are valid
The sa_commit_share entry point is provided as a performance enhancement
and is not required. The sa_enable_share/sa_disable_share may commit
the share as part of the implementation. Libshare provides a framework
for both NFS and SMB but some operating systems may not fully support
these protocols or all features of the protocol.
NFS Operation:
For linux, libshare updates /etc/exports.d/zfs.exports to add
and remove shares and then commits the changes by invoking
'exportfs -r'. This file, is automatically read by the kernel NFS
implementation which makes for better integration with the NFS systemd
service. For FreeBSD, libshare updates /etc/zfs/exports to add and
remove shares and then commits the changes by sending a SIGHUP to
mountd.
SMB Operation:
For linux, libshare adds and removes files in /var/lib/samba/usershares
by calling the 'net' command directly. There is no need to commit the
changes. FreeBSD does not support SMB.
== Performance Results
To test sharing performance we created a pool with an increasing number
of datasets and invoked various zfs actions that would enable and
disable sharing. The performance testing was limited to NFS sharing.
The following tests were performed on an 8 vCPU system with 128GB and
a pool comprised of 4 50GB SSDs:
Scale testing:
- Share all filesystems in parallel -- zfs sharenfs=on <dataset> &
- Unshare all filesystems in parallel -- zfs sharenfs=off <dataset> &
Functional testing:
- share each filesystem serially -- zfs share -a
- unshare each filesystem serially -- zfs unshare -a
- reset sharenfs property and unshare -- zfs inherit -r sharenfs <pool>
For 'zfs sharenfs=on' scale testing we saw an average reduction in time
of 89.43% and for 'zfs sharenfs=off' we saw an average reduction in time
of 83.36%.
Functional testing also shows a huge improvement:
- zfs share -- 97.97% reduction in time
- zfs unshare -- 96.47% reduction in time
- zfs inhert -r sharenfs -- 99.01% reduction in time
Reviewed-by: Matt Ahrens <matt@delphix.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Ryan Moeller <ryan@ixsystems.com>
Reviewed-by: Bryant G. Ly <bryangly@gmail.com>
Signed-off-by: George Wilson <gwilson@delphix.com>
External-Issue: DLPX-68690
Closes#1603Closes#7692Closes#7943Closes#10300
When zfs_mount_at() fails to stat the mountpoint and can't create the
directory, we return an error with a message "failed to create
mountpoint" but there is no indication why it failed.
Add the error string from the syscall to the error aux message.
Update do_mount for Linux to return the errno instead of -1.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Ryan Moeller <ryan@iXsystems.com>
Closes#10550
C++ is a little picky about not using keywords for names, or string
constness.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Jorgen Lundman <lundman@lundman.net>
Signed-off-by: Ryan Moeller <ryan@iXsystems.com>
Closes#10409
Allow zfs datasets to be mounted on Linux without relying on the
invocation of an external processes. This is the same behavior
which is implemented for FreeBSD.
Use of the libmount library was originally considered because it
provides functionality to properly lock and update the /etc/mtab
file. However, these days /etc/mtab is typically a symlink to
/proc/self/mounts so there's nothing to updated. Therefore, we
call mount(2) directly and avoid any additional dependencies.
If required the legacy behavior can be enabled by setting the
ZFS_MOUNT_HELPER environment variable. This may be needed in
environments where SELinux in enabled and the zfs binary does
not have mount permission.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Felix Dörre <felix@dogcraft.de>
#10294
Linux uses sysfs to determine the module version, FreeBSD uses a
different method.
Reviewed-by: Igor Kozhukhov <igor@dilos.org>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Ryan Moeller <ryan@iXsystems.com>
Closes#9978
Add the 'zfs jail/unjail' subcommands along with the relevant
documentation from FreeBSD. This feature is not supported on
Linux and still requires the match kernel ioctls which will
be included when the FreeBSD platform code is integrated.
Reviewed-by: Jorgen Lundman <lundman@lundman.net>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Matt Macy <mmacy@FreeBSD.org>
Signed-off-by: Ryan Moeller <ryan@ixsystems.com>
Closes#9686
Factor Linux specific functionality out of libzfs.
Reviewed-by: Allan Jude <allanjude@freebsd.org>
Reviewed-by: Jorgen Lundman <lundman@lundman.net>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Matthew Macy <mmacy@FreeBSD.org>
Closes#9377
