zfs/module/os/linux/spl
Richard Yao 7584fbe846
Cleanup: Switch to strlcpy from strncpy
Coverity found a bug in `zfs_secpolicy_create_clone()` where it is
possible for us to pass an unterminated string when `zfs_get_parent()`
returns an error. Upon inspection, it is clear that using `strlcpy()`
would have avoided this issue.

Looking at the codebase, there are a number of other uses of `strncpy()`
that are unsafe and even when it is used safely, switching to
`strlcpy()` would make the code more readable. Therefore, we switch all
instances where we use `strncpy()` to use `strlcpy()`.

Unfortunately, we do not portably have access to `strlcpy()` in
tests/zfs-tests/cmd/zfs_diff-socket.c because it does not link to
libspl. Modifying the appropriate Makefile.am to try to link to it
resulted in an error from the naming choice used in the file. Trying to
disable the check on the file did not work on FreeBSD because Clang
ignores `#undef` when a definition is provided by `-Dstrncpy(...)=...`.
We workaround that by explictly including the C file from libspl into
the test. This makes things build correctly everywhere.

We add a deprecation warning to `config/Rules.am` and suppress it on the
remaining `strncpy()` usage. `strlcpy()` is not portably avaliable in
tests/zfs-tests/cmd/zfs_diff-socket.c, so we use `snprintf()` there as a
substitute.

This patch does not tackle the related problem of `strcpy()`, which is
even less safe. Thankfully, a quick inspection found that it is used far
more correctly than strncpy() was used. A quick inspection did not find
any problems with `strcpy()` usage outside of zhack, but it should be
said that I only checked around 90% of them.

Lastly, some of the fields in kstat_t varied in size by 1 depending on
whether they were in userspace or in the kernel. The origin of this
discrepancy appears to be 04a479f706 where
it was made for no apparent reason. It conflicts with the comment on
KSTAT_STRLEN, so we shrink the kernel field sizes to match the userspace
field sizes.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Ryan Moeller <ryan@iXsystems.com>
Signed-off-by: Richard Yao <richard.yao@alumni.stonybrook.edu>
Closes #13876
2022-09-27 16:35:29 -07:00
..
README.md Replace ZFS on Linux references with OpenZFS 2020-10-08 20:10:13 -07:00
THIRDPARTYLICENSE.gplv2 OpenZFS restructuring - move platform specific sources 2019-09-06 11:26:26 -07:00
THIRDPARTYLICENSE.gplv2.descrip OpenZFS restructuring - move platform specific sources 2019-09-06 11:26:26 -07:00
spl-atomic.c Replace ZFS on Linux references with OpenZFS 2020-10-08 20:10:13 -07:00
spl-condvar.c Replace ZFS on Linux references with OpenZFS 2020-10-08 20:10:13 -07:00
spl-cred.c Fix ACL checks for NFS kernel server 2022-03-18 06:47:57 -06:00
spl-err.c spl: make 'spl_panic_halt' working for all cases 2022-02-18 11:43:11 -08:00
spl-generic.c Linux SPL module init: Handle memory allocation failures correctly 2022-09-08 10:28:20 -07:00
spl-kmem-cache.c Cleanup: Switch to strlcpy from strncpy 2022-09-27 16:35:29 -07:00
spl-kmem.c Clean up CSTYLEDs 2022-01-26 11:38:52 -08:00
spl-kstat.c Cleanup: Switch to strlcpy from strncpy 2022-09-27 16:35:29 -07:00
spl-proc.c Clean up CSTYLEDs 2022-01-26 11:38:52 -08:00
spl-procfs-list.c Replace dead opensolaris.org license link 2022-07-11 14:16:13 -07:00
spl-taskq.c Linux SPL module init: Handle memory allocation failures correctly 2022-09-08 10:28:20 -07:00
spl-thread.c Cleanup: Switch to strlcpy from strncpy 2022-09-27 16:35:29 -07:00
spl-trace.c Replace dead opensolaris.org license link 2022-07-11 14:16:13 -07:00
spl-tsd.c Linux SPL module init: Handle memory allocation failures correctly 2022-09-08 10:28:20 -07:00
spl-vmem.c Replace ZFS on Linux references with OpenZFS 2020-10-08 20:10:13 -07:00
spl-xdr.c module/*.ko: prune .data, global .rodata 2022-01-14 15:37:55 -08:00
spl-zlib.c Linux SPL module init: Handle memory allocation failures correctly 2022-09-08 10:28:20 -07:00
spl-zone.c Cleanup: Switch to strlcpy from strncpy 2022-09-27 16:35:29 -07:00

README.md

The Solaris Porting Layer, SPL, is a Linux kernel module which provides a compatibility layer used by the OpenZFS project.

Installation

The latest version of the SPL is maintained as part of this repository. Only when building ZFS version 0.7.x or earlier must an external SPL release be used. These releases can be found at:

Release

The SPL is released under a GPLv2 license.
For more details see the NOTICE and THIRDPARTYLICENSE files; UCRL-CODE-235197