The complicated part of multi_depend is the same as suffix-search.
Reuse it.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Split the code into two macros, cmd_gen_symversions_S for running
genksyms, and cmd_modversions for running $(LD) to update the object
with CRCs.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
cmd_modversions_c implements two parts; run genksyms to calculate CRCs
of exported symbols, run $(LD) to update the object with the CRCs. The
latter is not executed for CONFIG_LTO_CLANG=y since the object is not
ELF but LLVM bit code at this point.
The first part can be unified because we can always use $(NM) instead
of "$(OBJDUMP) -h" to dump the symbols.
Split the code into the two macros, cmd_gen_symversions_c and
cmd_modversions.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
There are two call sites for sym_update_namespace().
When the symbol has no namespace, s->namespace is set to NULL,
but the conversion from "" to NULL is done in two different places.
[1] read_symbols()
This gets the namespace from __kstrtabns_<symbol>. If the symbol has
no namespace, sym_get_data(info, sym) returns the empty string "".
namespace_from_kstrtabns() converts it to NULL before it is passed to
sym_update_namespace().
[2] read_dump()
This gets the namespace from the dump file, *.symvers. If the symbol
has no namespace, the 'namespace' is the empty string "", which is
directly passed into sym_update_namespace(). The conversion from
"" to NULL is done in sym_update_namespace().
namespace_from_kstrtabns() exists only for creating this inconsistency.
Remove namespace_from_kstrtabns() so that sym_update_namespace() is
consistently passed with "" instead of NULL.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
These are initialized with zeros without explicit initializers.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
The assigned 'export' is only used when
if (strstarts(symname, "__ksymtab_"))
is met. The else-part of the assignment is the dead code.
Move the export_from_secname() call to where it is used.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
With commit 1743694eb2 ("modpost: stop symbol preloading for
modversion CRC") applied, now export_from_sec() is useless.
handle_symbol() is called for every symbol in the ELF.
When 'symname' does not start with "__ksymtab", export_from_sec() is
called, and the returned value is stored in 'export'.
It is used in the last part of handle_symbol():
if (strstarts(symname, "__ksymtab_")) {
name = symname + strlen("__ksymtab_");
sym_add_exported(name, mod, export);
}
'export' is used only when 'symname' starts with "__ksymtab_".
So, the value returned by export_from_sec() is never used.
Remove useless export_from_sec(). This makes further cleanups possible.
I put the temporary code:
export = export_unknown;
Otherwise, I would get the compiler warning:
warning: 'export' may be used uninitialized in this function [-Wmaybe-uninitialized]
This is apparently false positive because
if (strstarts(symname, "__ksymtab_")
... is a stronger condition than:
if (strstarts(symname, "__ksymtab")
Anyway, this part will be cleaned up by the next commit.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
The arrays for the policy capability names, the initial sid identifiers
and the class and permission names are not changed at runtime. Declare
them const to avoid accidental modification.
Do not override the classmap and the initial sid list in the build time
script genheaders.
Check flose(3) is successful in genheaders.c, otherwise the written data
might be corrupted or incomplete.
Signed-off-by: Christian Göttsche <cgzones@googlemail.com>
[PM: manual merge due to fuzz, minor style tweaks]
Signed-off-by: Paul Moore <paul@paul-moore.com>
Old bash version don't support associative array variables. Avoid to use
associative array variables to avoid error.
Without this, old bash version will report error as fellowing
[ 15.954042] Kernel panic - not syncing: sysrq triggered crash
[ 15.955252] CPU: 1 PID: 167 Comm: sh Not tainted 5.18.0-rc1-00208-gb7d075db2fd5 #4
[ 15.956472] Hardware name: Hobot J5 Virtual development board (DT)
[ 15.957856] Call trace:
./scripts/decode_stacktrace.sh: line 128: ,dump_backtrace: syntax error: operand expected (error token is ",dump_backtrace")
Link: https://lkml.kernel.org/r/20220409180331.24047-1-schspa@gmail.com
Signed-off-by: Schspa Shi <schspa@gmail.com>
Cc: Stephen Boyd <swboyd@chromium.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reintroduce the __kvm_nvhe_ symbols in kallsyms, ignoring the local
symbols in this namespace. The local symbols are not informative and
can cause aliasing issues when symbolizing the addresses.
With the necessary symbols now in kallsyms we can symbolize nVHE
addresses using the %p print format specifier:
[ 98.916444][ T426] kvm [426]: nVHE hyp panic at: [<ffffffc0096156fc>] __kvm_nvhe_overflow_stack+0x8/0x34!
Signed-off-by: Kalesh Singh <kaleshsingh@google.com>
Tested-by: Fuad Tabba <tabba@google.com>
Reviewed-by: Fuad Tabba <tabba@google.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20220420214317.3303360-7-kaleshsingh@google.com
kvmalloc() and kvzalloc() functions have now 2-factor multiplication
argument forms kvmalloc_array() and kvcalloc(), correspondingly.
Add alloc-with-multiplies checks for these new functions.
Link: https://github.com/KSPP/linux/issues/187
Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
The '--lto' option is a confusing way of telling objtool to do stack
validation despite it being a linked object. It's no longer needed now
that an explicit '--stackval' option exists. The '--vmlinux' option is
also redundant.
Remove both options in favor of a straightforward '--link' option which
identifies a linked object.
Also, implicitly set '--link' with a warning if the user forgets to do
so and we can tell that it's a linked object. This makes it easier for
manual vmlinux runs.
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Miroslav Benes <mbenes@suse.cz>
Link: https://lkml.kernel.org/r/dcd3ceffd15a54822c6183e5766d21ad06082b45.1650300597.git.jpoimboe@redhat.com
Objtool has a fairly singular focus. It runs on object files and does
validations and transformations which can be combined in various ways.
The subcommand model has never been a good fit, making it awkward to
combine and remove options.
Remove the "check" and "orc" subcommands in favor of a more traditional
cmdline option model. This makes it much more flexible to use, and
easier to port individual features to other arches.
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Miroslav Benes <mbenes@suse.cz>
Link: https://lkml.kernel.org/r/5c61ebf805e90aefc5fa62bc63468ffae53b9df6.1650300597.git.jpoimboe@redhat.com
Split the existing options into two groups: actions, which actually do
something; and options, which modify the actions in some way.
Also there's no need to have short flags for all the non-action options.
Reserve short flags for the more important actions.
While at it:
- change a few of the short flags to be more intuitive
- make option descriptions more consistently descriptive
- sort options in the source like they are when printed
- move options to a global struct
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Miroslav Benes <mbenes@suse.cz>
Link: https://lkml.kernel.org/r/9dcaa752f83aca24b1b21f0b0eeb28a0c181c0b0.1650300597.git.jpoimboe@redhat.com
The initialization of "security_hook_heads" is done by casting it to
another structure pointer type, and treating it as an array of "struct
hlist_head" objects. This requires an exception be made in "randstruct",
because otherwise it will emit an error, reducing the effectiveness of
the hardening technique.
Instead of using a cast, initialize the individual struct hlist_head
elements in security_hook_heads explicitly. This removes the need for
the cast and randstruct exception.
Signed-off-by: Bill Wendling <morbo@google.com>
Cc: Kees Cook <keescook@chromium.org>
Signed-off-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20220407175930.471870-1-morbo@google.com
Pull hardening fixes from Kees Cook:
- latent_entropy: Use /dev/urandom instead of small GCC seed (Jason
Donenfeld)
- uapi/stddef.h: add missed include guards (Tadeusz Struk)
* tag 'hardening-v5.18-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux:
gcc-plugins: latent_entropy: use /dev/urandom
uapi/linux/stddef.h: Add include guards
While the latent entropy plugin mostly doesn't derive entropy from
get_random_const() for measuring the call graph, when __latent_entropy is
applied to a constant, then it's initialized statically to output from
get_random_const(). In that case, this data is derived from a 64-bit
seed, which means a buffer of 512 bits doesn't really have that amount
of compile-time entropy.
This patch fixes that shortcoming by just buffering chunks of
/dev/urandom output and doling it out as requested.
At the same time, it's important that we don't break the use of
-frandom-seed, for people who want the runtime benefits of the latent
entropy plugin, while still having compile-time determinism. In that
case, we detect whether gcc's set_random_seed() has been called by
making a call to get_random_seed(noinit=true) in the plugin init
function, which is called after set_random_seed() is called but before
anything that calls get_random_seed(noinit=false), and seeing if it's
zero or not. If it's not zero, we're in deterministic mode, and so we
just generate numbers with a basic xorshift prng.
Note that we don't detect if -frandom-seed is being used using the
documented local_tick variable, because it's assigned via:
local_tick = (unsigned) tv.tv_sec * 1000 + tv.tv_usec / 1000;
which may well overflow and become -1 on its own, and so isn't
reliable: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=105171
[kees: The 256 byte rnd_buf size was chosen based on average (250),
median (64), and std deviation (575) bytes of used entropy for a
defconfig x86_64 build]
Fixes: 38addce8b6 ("gcc-plugins: Add latent_entropy plugin")
Cc: stable@vger.kernel.org
Cc: PaX Team <pageexec@freemail.hu>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20220405222815.21155-1-Jason@zx2c4.com
Presumably, 'test -s $@ || rm -f $@' intends to remove the output when
the genksyms command fails.
It is unneeded because .DELETE_ON_ERROR automatically removes the output
on failure.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Reviewed-by: Nicolas Schier <nicolas@fjasle.eu>
The genksyms command part in cmd_gensymtypes_{c,S} is duplicated.
Factor it out into the 'genksyms' macro.
For the readability, I slightly refactor the arguments to genksyms.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Reviewed-by: Nicolas Schier <nicolas@fjasle.eu>
Add HOSTPKG_CONFIG to allow tooling that builds the kernel to override
what pkg-config and parameters are used.
Signed-off-by: Chun-Tse Shao <ctshao@google.com>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Those were added as part of the SMAP enablement but SMAP is currently
an integral part of kernel proper and there's no need to disable it
anymore.
Rip out that functionality. Leave --uaccess default on for objtool as
this is what objtool should do by default anyway.
If still needed - clearcpuid=smap.
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Lai Jiangshan <jiangshanlai@gmail.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20220127115626.14179-4-bp@alien8.de
The two commits
d8d2d38275 ("kbuild: remove PYTHON variable")
a8cccdd954 ("init: lto: ensure initcall ordering")
were applied in the same development cycle, into two different trees.
After they were merged together, this ${PYTHON} expands to an empty
string.
Therefore, ${srctree}/scripts/jobserver-exec is executed directly.
(it has the executable bit set)
This is working but let's fix the code into the intended form.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Reviewed-by: Sedat Dilek <sedat.dilek@gmail.com>
This comment is about kconfig_print_symbol(), which was removed by
commit 6ce45a91a9 ("kconfig: refactor conf_write_symbol()").
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Pull more documentation updates from Jonathan Corbet:
"Some late-arriving documentation improvements.
This is mostly build-system fixes from Mauro and Akira; I also took
the liberty of dropping in my 'messy diffstat' document"
* tag 'docs-5.18-2' of git://git.lwn.net/linux:
docs: Add a document on how to fix a messy diffstat
docs: sphinx/requirements: Limit jinja2<3.1
Documentation: kunit: Fix cross-referencing warnings
scripts/kernel-doc: change the line number meta info
scripts/get_abi: change the file/line number meta info
docs: kernel_include.py: add sphinx build dependencies
docs: kernel_abi.py: add sphinx build dependencies
docs: kernel_feat.py: add build dependencies
scripts/get_feat.pl: allow output the parsed file names
docs: kfigure.py: Don't warn of missing PDF converter in 'make htmldocs'
Documentation: Fix duplicate statement about raw_spinlock_t type
Pull Kbuild updates from Masahiro Yamada:
- Add new environment variables, USERCFLAGS and USERLDFLAGS to allow
additional flags to be passed to user-space programs.
- Fix missing fflush() bugs in Kconfig and fixdep
- Fix a minor bug in the comment format of the .config file
- Make kallsyms ignore llvm's local labels, .L*
- Fix UAPI compile-test for cross-compiling with Clang
- Extend the LLVM= syntax to support LLVM=<suffix> form for using a
particular version of LLVm, and LLVM=<prefix> form for using custom
LLVM in a particular directory path.
- Clean up Makefiles
* tag 'kbuild-v5.18-v2' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild:
kbuild: Make $(LLVM) more flexible
kbuild: add --target to correctly cross-compile UAPI headers with Clang
fixdep: use fflush() and ferror() to ensure successful write to files
arch: syscalls: simplify uapi/kapi directory creation
usr/include: replace extra-y with always-y
certs: simplify empty certs creation in certs/Makefile
certs: include certs/signing_key.x509 unconditionally
kallsyms: ignore all local labels prefixed by '.L'
kconfig: fix missing '# end of' for empty menu
kconfig: add fflush() before ferror() check
kbuild: replace $(if A,A,B) with $(or A,B)
kbuild: Add environment variables for userprogs flags
kbuild: unify cmd_copy and cmd_shipped
Currently, fixdep checks the return value from (v)printf(), but it does
not ensure the complete write to the .cmd file.
printf() just writes data to the internal buffer, which usually succeeds.
(Of course, it may fail for another reason, for example when the file
descriptor is closed, but that is another story.)
When the buffer (4k?) is full, an actual write occurs, and printf() may
really fail. One of typical cases is "No space left on device" when the
disk is full.
The data remaining in the buffer will be pushed out to the file when
the program exits, but we never know if it is successful.
One straight-forward fix would be to add the following code at the end
of the program.
ret = fflush(stdout);
if (ret < 0) {
/* error handling */
}
However, it is tedious to check the return code in all the call sites
of printf(), fflush(), fclose(), and whatever can cause actual writes
to the end device. Doing that lets the program bail out at the first
failure but is usually not worth the effort.
Instead, let's check the error status from ferror(). This is 'sticky',
so you need to check it just once. You still need to call fflush().
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: David Laight <david.laight@aculab.com>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Pull driver core updates from Greg KH:
"Here is the set of driver core changes for 5.18-rc1.
Not much here, primarily it was a bunch of cleanups and small updates:
- kobj_type cleanups for default_groups
- documentation updates
- firmware loader minor changes
- component common helper added and take advantage of it in many
drivers (the largest part of this pull request).
All of these have been in linux-next for a while with no reported
problems"
* tag 'driver-core-5.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (54 commits)
Documentation: update stable review cycle documentation
drivers/base/dd.c : Remove the initial value of the global variable
Documentation: update stable tree link
Documentation: add link to stable release candidate tree
devres: fix typos in comments
Documentation: add note block surrounding security patch note
samples/kobject: Use sysfs_emit instead of sprintf
base: soc: Make soc_device_match() simpler and easier to read
driver core: dd: fix return value of __setup handler
driver core: Refactor sysfs and drv/bus remove hooks
driver core: Refactor multiple copies of device cleanup
scripts: get_abi.pl: Fix typo in help message
kernfs: fix typos in comments
kernfs: remove unneeded #if 0 guard
ALSA: hda/realtek: Make use of the helper component_compare_dev_name
video: omapfb: dss: Make use of the helper component_compare_dev
power: supply: ab8500: Make use of the helper component_compare_dev
ASoC: codecs: wcd938x: Make use of the helper component_compare/release_of
iommu/mediatek: Make use of the helper component_compare/release_of
drm: of: Make use of the helper component_release_of
...
Pull x86 CET-IBT (Control-Flow-Integrity) support from Peter Zijlstra:
"Add support for Intel CET-IBT, available since Tigerlake (11th gen),
which is a coarse grained, hardware based, forward edge
Control-Flow-Integrity mechanism where any indirect CALL/JMP must
target an ENDBR instruction or suffer #CP.
Additionally, since Alderlake (12th gen)/Sapphire-Rapids, speculation
is limited to 2 instructions (and typically fewer) on branch targets
not starting with ENDBR. CET-IBT also limits speculation of the next
sequential instruction after the indirect CALL/JMP [1].
CET-IBT is fundamentally incompatible with retpolines, but provides,
as described above, speculation limits itself"
[1] https://www.intel.com/content/www/us/en/developer/articles/technical/software-security-guidance/technical-documentation/branch-history-injection.html
* tag 'x86_core_for_5.18_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (53 commits)
kvm/emulate: Fix SETcc emulation for ENDBR
x86/Kconfig: Only allow CONFIG_X86_KERNEL_IBT with ld.lld >= 14.0.0
x86/Kconfig: Only enable CONFIG_CC_HAS_IBT for clang >= 14.0.0
kbuild: Fixup the IBT kbuild changes
x86/Kconfig: Do not allow CONFIG_X86_X32_ABI=y with llvm-objcopy
x86: Remove toolchain check for X32 ABI capability
x86/alternative: Use .ibt_endbr_seal to seal indirect calls
objtool: Find unused ENDBR instructions
objtool: Validate IBT assumptions
objtool: Add IBT/ENDBR decoding
objtool: Read the NOENDBR annotation
x86: Annotate idtentry_df()
x86,objtool: Move the ASM_REACHABLE annotation to objtool.h
x86: Annotate call_on_stack()
objtool: Rework ASM_REACHABLE
x86: Mark __invalid_creds() __noreturn
exit: Mark do_group_exit() __noreturn
x86: Mark stop_this_cpu() __noreturn
objtool: Ignore extra-symbol code
objtool: Rename --duplicate to --lto
...
Pull FORTIFY_SOURCE updates from Kees Cook:
"This series consists of two halves:
- strict compile-time buffer size checking under FORTIFY_SOURCE for
the memcpy()-family of functions (for extensive details and
rationale, see the first commit)
- enabling FORTIFY_SOURCE for Clang, which has had many overlapping
bugs that we've finally worked past"
* tag 'memcpy-v5.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux:
fortify: Add Clang support
fortify: Make sure strlen() may still be used as a constant expression
fortify: Use __diagnose_as() for better diagnostic coverage
fortify: Make pointer arguments const
Compiler Attributes: Add __diagnose_as for Clang
Compiler Attributes: Add __overloadable for Clang
Compiler Attributes: Add __pass_object_size for Clang
fortify: Replace open-coded __gnu_inline attribute
fortify: Update compile-time tests for Clang 14
fortify: Detect struct member overflows in memset() at compile-time
fortify: Detect struct member overflows in memmove() at compile-time
fortify: Detect struct member overflows in memcpy() at compile-time
Pull devicetree updates from Rob Herring:
- Add Krzysztof Kozlowski as co-maintainer for DT bindings providing
much needed help.
- DT schema validation now takes DTB files as input rather than
intermediate YAML files. This decouples the validation from the
source level syntax information. There's a bunch of schema fixes as a
result of switching to DTB based validation which exposed some errors
and incomplete schemas and examples.
- Kbuild improvements to explicitly warn users running 'make
dt_binding_check' on missing yamllint
- Expand DT_SCHEMA_FILES kbuild variable to take just a partial
filename or path instead of the full path to 1 file.
- Convert various bindings to schema format: mscc,vsc7514-switch,
multiple GNSS bindings, ahci-platform, i2c-at91, multiple UFS
bindings, cortina,gemini-sata-bridge, cortina,gemini-ethernet, Atmel
SHA, Atmel TDES, Atmel AES, armv7m-systick, Samsung Exynos display
subsystem, nuvoton,npcm7xx-timer, samsung,s3c2410-i2c, zynqmp_dma,
msm/mdp4, rda,8810pl-uart
- New schemas for u-boot environment variable partition, TI clksel
- New compatible strings for Renesas RZ/V2L SoC
- Vendor prefixes for Xen, HPE, deprecated Synopsys, deprecated
HiSilicon
- Add/fix schemas for QEMU Arm 'virt' machine
- Drop unused of_alias_get_alias_list() function
- Add a script to check DT unittest EXPECT message output. Pass
messages also now print by default at PR_INFO level to help test
automation.
* tag 'devicetree-for-5.18' of git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux: (96 commits)
dt-bindings: kbuild: Make DT_SCHEMA_LINT a recursive variable
dt-bindings: nvmem: add U-Boot environment variables binding
dt-bindings: ufs: qcom: Add SM6350 compatible string
dt-bindings: dmaengine: sifive,fu540-c000: include generic schema
dt-bindings: gpio: pca95xx: drop useless consumer example
Revert "of: base: Introduce of_alias_get_alias_list() to check alias IDs"
dt-bindings: virtio,mmio: Allow setting devices 'dma-coherent'
dt-bindings: gnss: Add two more chips
dt-bindings: gnss: Rewrite sirfstar binding in YAML
dt-bindings: gnss: Modify u-blox to use common bindings
dt-bindings: gnss: Rewrite common bindings in YAML
dt-bindings: ata: ahci-platform: Add rk3568-dwc-ahci compatible
dt-bindings: ata: ahci-platform: Add power-domains property
dt-bindings: ata: ahci-platform: Convert DT bindings to yaml
dt-bindings: kbuild: Use DTB files for validation
dt-bindings: kbuild: Pass DT_SCHEMA_FILES to dt-validate
dt-bindings: Add QEMU virt machine compatible
dt-bindings: arm: Convert QEMU fw-cfg to DT schema
dt-bindings: i2c: at91: Add SAMA7G5 compatible strings list
dt-bindings: i2c: convert i2c-at91 to json-schema
...
Pull Kbuild update for C11 language base from Masahiro Yamada:
"Kbuild -std=gnu11 updates for v5.18
Linus pointed out the benefits of C99 some years ago, especially
variable declarations in loops [1]. At that time, we were not ready
for the migration due to old compilers.
Recently, Jakob Koschel reported a bug in list_for_each_entry(), which
leaks the invalid pointer out of the loop [2]. In the discussion, we
agreed that the time had come. Now that GCC 5.1 is the minimum
compiler version, there is nothing to prevent us from going to
-std=gnu99, or even straight to -std=gnu11.
Discussions for a better list iterator implementation are ongoing, but
this patch set must land first"
[1] https://lore.kernel.org/all/CAHk-=wgr12JkKmRd21qh-se-_Gs69kbPgR9x4C+Es-yJV2GLkA@mail.gmail.com/
[2] https://lore.kernel.org/lkml/86C4CE7D-6D93-456B-AA82-F8ADEACA40B7@gmail.com/
* tag 'kbuild-gnu11-v5.18' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild:
Kbuild: use -std=gnu11 for KBUILD_USERCFLAGS
Kbuild: move to -std=gnu11
Kbuild: use -Wdeclaration-after-statement
Kbuild: add -Wno-shift-negative-value where -Wextra is used
