There is a regular need in the kernel to provide a way to declare
having a dynamically sized set of trailing elements in a structure.
Kernel code should always use “flexible array members”[1] for these
cases. The older style of one-element or zero-length arrays should
no longer be used[2].
This code was transformed with the help of Coccinelle:
(linux-5.19-rc2$ spatch --jobs $(getconf _NPROCESSORS_ONLN) --sp-file script.cocci --include-headers --dir . > output.patch)
@@
identifier S, member, array;
type T1, T2;
@@
struct S {
...
T1 member;
T2 array[
- 0
];
};
-fstrict-flex-arrays=3 is coming and we need to land these changes
to prevent issues like these in the short future:
../fs/minix/dir.c:337:3: warning: 'strcpy' will always overflow; destination buffer has size 0,
but the source string has length 2 (including NUL byte) [-Wfortify-source]
strcpy(de3->name, ".");
^
Since these are all [0] to [] changes, the risk to UAPI is nearly zero. If
this breaks anything, we can use a union with a new member name.
[1] https://en.wikipedia.org/wiki/Flexible_array_member
[2] https://www.kernel.org/doc/html/v5.16/process/deprecated.html#zero-length-and-one-element-arrays
Link: https://github.com/KSPP/linux/issues/78
Build-tested-by: kernel test robot <lkp@intel.com>
Link: https://lore.kernel.org/lkml/62b675ec.wKX6AOZ6cbE71vtF%25lkp@intel.com/
Acked-by: Dan Williams <dan.j.williams@intel.com> # For ndctl.h
Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Pull quota, ext2, isofs and udf fixes from Jan Kara:
- two small quota error handling fixes
- two isofs fixes for architectures with signed char
- several udf block number overflow and signedness fixes
- ext2 rework of mount option handling to avoid GFP_KERNEL allocation
with spinlock held
- ... it also contains a patch to implement auditing of responses to
fanotify permission events. That should have been in the fanotify
pull request but I mistakenly merged that patch into a wrong branch
and noticed only now at which point I don't think it's worth rebasing
and redoing.
* 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs:
quota: be aware of error from dquot_initialize
quota: fix potential infinite loop
isofs: use unsigned char types consistently
isofs: fix timestamps beyond 2027
udf: Fix some sign-conversion warnings
udf: Fix signed/unsigned format specifiers
udf: Fix 64-bit sign extension issues affecting blocks > 0x7FFFFFFF
udf: Remove some outdate references from documentation
udf: Avoid overflow when session starts at large offset
ext2: Fix possible sleep in atomic during mount option parsing
ext2: Parse mount options into a dedicated structure
audit: Record fanotify access control decisions
Many user space API headers are missing licensing information, which
makes it hard for compliance tools to determine the correct license.
By default are files without license information under the default
license of the kernel, which is GPLV2. Marking them GPLV2 would exclude
them from being included in non GPLV2 code, which is obviously not
intended. The user space API headers fall under the syscall exception
which is in the kernels COPYING file:
NOTE! This copyright does *not* cover user programs that use kernel
services by normal system calls - this is merely considered normal use
of the kernel, and does *not* fall under the heading of "derived work".
otherwise syscall usage would not be possible.
Update the files which contain no license information with an SPDX
license identifier. The chosen identifier is 'GPL-2.0 WITH
Linux-syscall-note' which is the officially assigned identifier for the
Linux syscall exception. SPDX license identifiers are a legally binding
shorthand, which can be used instead of the full boiler plate text.
This patch is based on work done by Thomas Gleixner and Kate Stewart and
Philippe Ombredanne. See the previous patch in this series for the
methodology of how this patch was researched.
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Based on the discussion about the signed character field for the year,
I went through all fields in the iso9660 and rockridge standards to see
whether they should used signed or unsigned characters. Only a single
8-bit value is defined as signed per 'section 7.1.2': the timezone
offset in a timestamp, this has always been handled correctly through
explicit sign-extension.
All others are either '7.1.1 8-bit unsigned numerical values' or
composite fields. I also read the linux source code and came to the
same conclusion, also I could not find any other part of the
implementation that actually behaves differently for signed or
unsigned values.
Since it is still ambigous to use plain 'char' in interface definitions,
I'm changing all fields representing numbers and reserved bytes to
the unambiguous '__u8'. Fields that hold actual strings are left as
'char' arrays. I built the code with '-Wpointer-sign -Wsign-compare'
to see if anything got left out, but couldn't find anything wrong
with the remaining warnings.
This patch should not change runtime behavior and does not need to
be backported.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Michael Kerrisk <mtk.manpages@gmail.com>
Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Acked-by: Dave Jones <davej@redhat.com>
Gustavo A. R. Silva