The initial FUSE passthrough interface has the issue of introducing an
ioctl which receives as a parameter a data structure containing a
pointer. What happens is that, depending on the architecture, the size
of this struct might change, and especially for 32-bit userspace running
on 64-bit kernel, the size mismatch results into different a single
ioctl the behavior of which depends on the data that is passed (e.g.,
with an enum). This is just a poor ioctl design as mentioned by Arnd
Bergmann [1].
Introduce the new FUSE_PASSTHROUGH_OPEN ioctl which only gets the fd of
the lower file system, which is a fixed-size __u32, dropping the
confusing fuse_passthrough_out data structure.
[1] https://lore.kernel.org/lkml/CAK8P3a2K2FzPvqBYL9W=Yut58SFXyetXwU4Fz50G5O3TsS0pPQ@mail.gmail.com/
Bug: 175195837
Signed-off-by: Alessio Balsini <balsini@google.com>
Change-Id: I486d71cbe20f3c0c87544fa75da4e2704fe57c7c
[cyberknight777: backport to 4.14]
Signed-off-by: Cyber Knight <cyberknight755@gmail.com>
Signed-off-by: onettboots <blackcocopet@gmail.com>
introduce a new ioctl to replace the whole content of a file atomically,
which means it induces truncate and content update at the same time.
We can start it with F2FS_IOC_START_ATOMIC_REPLACE and complete it with
F2FS_IOC_COMMIT_ATOMIC_WRITE. Or abort it with
F2FS_IOC_ABORT_ATOMIC_WRITE.
Signed-off-by: Daeho Jeong <daehojeong@google.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
commit 1202cdd665315c525b5237e96e0bedc76d7e754f upstream.
DECnet is an obsolete network protocol that receives more attention
from kernel janitors than users. It belongs in computer protocol
history museum not in Linux kernel.
It has been "Orphaned" in kernel since 2010. The iproute2 support
for DECnet was dropped in 5.0 release. The documentation link on
Sourceforge says it is abandoned there as well.
Leave the UAPI alone to keep userspace programs compiling.
This means that there is still an empty neighbour table
for AF_DECNET.
The table of /proc/sys/net entries was updated to match
current directories and reformatted to be alphabetical.
Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
Acked-by: David Ahern <dsahern@kernel.org>
Acked-by: Nikolay Aleksandrov <razor@blackwall.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ 215a31f19dedd4e92a67cf5a9717ee898d012b3a ]
NFT_SET_EVAL is signalling the kernel that this sets can be updated from
the evaluation path, even if there are no expressions attached to the
element. Otherwise, set updates with no expressions fail. Update
description to describe the right semantics.
Fixes: 22fe54d5fe ("netfilter: nf_tables: add support for dynamic set updates")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 604e6681e114d05a2e384c4d1e8ef81918037ef5 upstream.
Since the introduction of scrub interface, the only flag that we support
is BTRFS_SCRUB_READONLY. Thus there is no sanity checks, if there are
some undefined flags passed in, we just ignore them.
This is problematic if we want to introduce new scrub flags, as we have
no way to determine if such flags are supported.
Address the problem by introducing a check for the flags, and if
unsupported flags are set, return -EOPNOTSUPP to inform the user space.
This check should be backported for all supported kernels before any new
scrub flags are introduced.
CC: stable@vger.kernel.org # 4.14+
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 31088f6f7906253ef4577f6a9b84e2d42447dba0 ]
typeof is (still) a GNU extension, which means that it cannot be used when
building ISO C (e.g. -std=c99). It should therefore be avoided in uapi
headers in favour of the ISO-friendly __typeof__.
Unfortunately this issue could not be detected by
CONFIG_UAPI_HEADER_TEST=y as the __ALIGN_KERNEL() macro is not expanded in
any uapi header.
This matters from a userspace perspective, not a kernel one. uapi
headers and their contents are expected to be usable in a variety of
situations, and in particular when building ISO C applications (with
-std=c99 or similar).
This particular problem can be reproduced by trying to use the
__ALIGN_KERNEL macro directly in application code, say:
#include <linux/const.h>
int align(int x, int a)
{
return __KERNEL_ALIGN(x, a);
}
and trying to build that with -std=c99.
Link: https://lkml.kernel.org/r/20230411092747.3759032-1-kevin.brodsky@arm.com
Fixes: a79ff731a1 ("netfilter: xtables: make XT_ALIGN() usable in exported headers by exporting __ALIGN_KERNEL()")
Signed-off-by: Kevin Brodsky <kevin.brodsky@arm.com>
Reported-by: Ruben Ayrapetyan <ruben.ayrapetyan@arm.com>
Tested-by: Ruben Ayrapetyan <ruben.ayrapetyan@arm.com>
Reviewed-by: Petr Vorel <pvorel@suse.cz>
Tested-by: Petr Vorel <pvorel@suse.cz>
Reviewed-by: Masahiro Yamada <masahiroy@kernel.org>
Cc: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit defbab270d45e32b068e7e73c3567232d745c60f ]
Commit bc27fb68aa ("include/uapi/linux/byteorder, swab: force inlining
of some byteswap operations") added __always_inline to swab functions
and commit 283d757378 ("uapi/linux/stddef.h: Provide __always_inline to
userspace headers") added a definition of __always_inline for use in
exported headers when the kernel's compiler.h is not available.
However, since swab.h does not include stddef.h, if the header soup does
not indirectly include it, the definition of __always_inline is missing,
resulting in a compilation failure, which was observed compiling the
perf tool using exported headers containing this commit:
In file included from /usr/include/linux/byteorder/little_endian.h:12:0,
from /usr/include/asm/byteorder.h:14,
from tools/include/uapi/linux/perf_event.h:20,
from perf.h:8,
from builtin-bench.c:18:
/usr/include/linux/swab.h:160:8: error: unknown type name `__always_inline'
static __always_inline __u16 __swab16p(const __u16 *p)
Fix this by replacing the inclusion of linux/compiler.h with
linux/stddef.h to ensure that we pick up that definition if required,
without relying on it's indirect inclusion. compiler.h is then included
indirectly, via stddef.h.
Fixes: 283d757378 ("uapi/linux/stddef.h: Provide __always_inline to userspace headers")
Signed-off-by: Matt Redfearn <matt.redfearn@mips.com>
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Tested-by: Nathan Chancellor <nathan@kernel.org>
Reviewed-by: Petr Vaněk <arkamar@atlas.cz>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit cf59e1e4c79bf741905484cdb13c130b53576a16 ]
Shifting signed 32-bit value by 31 bits is undefined, so changing
significant bit to unsigned. The UBSAN warning calltrace like below:
UBSAN: shift-out-of-bounds in sound/core/seq/seq_clientmgr.c:509:22
left shift of 1 by 31 places cannot be represented in type 'int'
...
Call Trace:
<TASK>
dump_stack_lvl+0x8d/0xcf
ubsan_epilogue+0xa/0x44
__ubsan_handle_shift_out_of_bounds+0x1e7/0x208
snd_seq_deliver_single_event.constprop.21+0x191/0x2f0
snd_seq_deliver_event+0x1a2/0x350
snd_seq_kernel_client_dispatch+0x8b/0xb0
snd_seq_client_notify_subscription+0x72/0xa0
snd_seq_ioctl_subscribe_port+0x128/0x160
snd_seq_kernel_client_ctl+0xce/0xf0
snd_seq_oss_create_client+0x109/0x15b
alsa_seq_oss_init+0x11c/0x1aa
do_one_initcall+0x80/0x440
kernel_init_freeable+0x370/0x3c3
kernel_init+0x1b/0x190
ret_from_fork+0x1f/0x30
</TASK>
Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Signed-off-by: Baisong Zhong <zhongbaisong@huawei.com>
Link: https://lore.kernel.org/r/20221121111630.3119259-1-zhongbaisong@huawei.com
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
We allow more then 255 binderfs binder devices to be created since there
are workloads that require more than that. If we use __u8 we'll overflow
after 255. So let's use a __u32.
Note that there's no released kernel with binderfs out there so this is
not a regression.
Signed-off-by: Christian Brauner <christian@brauner.io>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
(cherry picked from commit 7d0174065f4903fb0ce0bab3d5047284faa7226d)
Bug: 228263403
Signed-off-by: Carlos Llamas <cmllamas@google.com>
Change-Id: If143c0d6511946fac6349c5db7c013535950de4a
Git-commit: 1848ba7e35
Git-repo: https://android.googlesource.com/kernel/common/
Signed-off-by: Srinivasarao Pathipati <quic_c_spathi@quicinc.com>
[ Upstream commit 986d93f55bdeab1cac858d1e47b41fac10b2d7f6 ]
Shifting signed 32-bit value by 31 bits is undefined, so changing
significant bit to unsigned. The UBSAN warning calltrace like below:
UBSAN: shift-out-of-bounds in kernel/auditfilter.c:179:23
left shift of 1 by 31 places cannot be represented in type 'int'
Call Trace:
<TASK>
dump_stack_lvl+0x7d/0xa5
dump_stack+0x15/0x1b
ubsan_epilogue+0xe/0x4e
__ubsan_handle_shift_out_of_bounds+0x1e7/0x20c
audit_register_class+0x9d/0x137
audit_classes_init+0x4d/0xb8
do_one_initcall+0x76/0x430
kernel_init_freeable+0x3b3/0x422
kernel_init+0x24/0x1e0
ret_from_fork+0x1f/0x30
</TASK>
Signed-off-by: Gaosheng Cui <cuigaosheng1@huawei.com>
[PM: remove bad 'Fixes' tag as issue predates git, added in v2.6.6-rc1]
Signed-off-by: Paul Moore <paul@paul-moore.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 46653972e3ea64f79e7f8ae3aa41a4d3fdb70a13 ]
Shifting signed 32-bit value by 31 bits is undefined, so changing
significant bit to unsigned. The UBSAN warning calltrace like below:
UBSAN: shift-out-of-bounds in security/commoncap.c:1252:2
left shift of 1 by 31 places cannot be represented in type 'int'
Call Trace:
<TASK>
dump_stack_lvl+0x7d/0xa5
dump_stack+0x15/0x1b
ubsan_epilogue+0xe/0x4e
__ubsan_handle_shift_out_of_bounds+0x1e7/0x20c
cap_task_prctl+0x561/0x6f0
security_task_prctl+0x5a/0xb0
__x64_sys_prctl+0x61/0x8f0
do_syscall_64+0x58/0x80
entry_SYSCALL_64_after_hwframe+0x63/0xcd
</TASK>
Fixes: e338d263a7 ("Add 64-bit capability support to the kernel")
Signed-off-by: Gaosheng Cui <cuigaosheng1@huawei.com>
Acked-by: Andrew G. Morgan <morgan@kernel.org>
Reviewed-by: Serge Hallyn <serge@hallyn.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit 2a6cc8a6c0cb44baf7df2f64e5090aaf726002c3 upstream.
Patch series "linux/const.h: cleanups of macros such as UL(), _BITUL(),
BIT() etc", v3.
ARM, ARM64, UniCore32 define UL() as a shorthand of _AC(..., UL). More
architectures may introduce it in the future.
UL() is arch-agnostic, and useful. So let's move it to
include/linux/const.h
Currently, <asm/memory.h> must be included to use UL(). It pulls in more
bloats just for defining some bit macros.
I posted V2 one year ago.
The previous posts are:
https://patchwork.kernel.org/patch/9498273/https://patchwork.kernel.org/patch/9498275/https://patchwork.kernel.org/patch/9498269/https://patchwork.kernel.org/patch/9498271/
At that time, what blocked this series was a comment from
David Howells:
You need to be very careful doing this. Some userspace stuff
depends on the guard macro names on the kernel header files.
(https://patchwork.kernel.org/patch/9498275/)
Looking at the code closer, I noticed this is not a problem.
See the following line.
https://github.com/torvalds/linux/blob/v4.16-rc2/scripts/headers_install.sh#L40
scripts/headers_install.sh rips off _UAPI prefix from guard macro names.
I ran "make headers_install" and confirmed the result is what I expect.
So, we can prefix the include guard of include/uapi/linux/const.h,
and add a new include/linux/const.h.
This patch (of 4):
I am going to add include/linux/const.h for the kernel space.
Add _UAPI to the include guard of include/uapi/linux/const.h to
prepare for that.
Please notice the guard name of the exported one will be kept as-is.
So, this commit has no impact to the userspace even if some userspace
stuff depends on the guard macro names.
scripts/headers_install.sh processes exported headers by SED, and
rips off "_UAPI" from guard macro names.
#ifndef _UAPI_LINUX_CONST_H
#define _UAPI_LINUX_CONST_H
will be turned into
#ifndef _LINUX_CONST_H
#define _LINUX_CONST_H
Link: http://lkml.kernel.org/r/1519301715-31798-2-git-send-email-yamada.masahiro@socionext.com
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Cc: David Howells <dhowells@redhat.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Guan Xuetao <gxt@mprc.pku.edu.cn>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Russell King <rmk+kernel@armlinux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
[nd: resolve trivial conflict due to b732e14e62 being backported before this]
Signed-off-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 8da7f0976b9071b528c545008de9d10cc81883b1 ]
If it is a progressive (non-interlaced) format, then ignore the
interlaced timing values.
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Fixes: 7f68127fa1 ([media] videodev2.h: defines to calculate blanking and frame sizes)
Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Bug: 186796876
Test: incfs_test passes
Signed-off-by: Paul Lawrence <paullawrence@google.com>
Change-Id: I552cae5e87b004202364ba5c9c5f9febb9e106f2
Signed-off-by: Andrzej Perczak <linux@andrzejperczak.com>
Bug: 184291759
Test: incfs_test passes
Signed-off-by: Paul Lawrence <paullawrence@google.com>
Change-Id: If46e91f9c992337d53970573c238be965187761e
Signed-off-by: Andrzej Perczak <linux@andrzejperczak.com>
Sparse complains about casting a five byte number to a ulong on 32-bit
platorms. Fix by anding the constant with ULONG_MAX
Bug: 186015158
Test: incfs_test passes, sparse reports no warnings on 32 & 64 bit builds
Signed-off-by: Paul Lawrence <paullawrence@google.com>
Change-Id: Ic83e03626b7f290370d75b3aaba187b8392fb344
Signed-off-by: Andrzej Perczak <linux@andrzejperczak.com>
Now fsverity state is preserved across inode eviction.
Added incfs.verity xattr to track when a file is fs-verity enabled.
Bug: 160634504
Test: incfs_test passes
Signed-off-by: Paul Lawrence <paullawrence@google.com>
Change-Id: I908a80dc9d956d0fbaa59b40c249de850e887820
Signed-off-by: Andrzej Perczak <linux@andrzejperczak.com>
Bug: 175323815
Test: incfs_test passes
Signed-off-by: Paul Lawrence <paullawrence@google.com>
Change-Id: I0df482e225b85321703b442afdf6f175b9cc3ab7
Signed-off-by: Andrzej Perczak <linux@andrzejperczak.com>
Google changed their mind about incfs and reverted all v2 related
changes. Lets bring it back.
This commit was created by checking out commit 8278cda5d9
(ANDROID: Incremental fs: Set credentials before reading/writing)
and picking some changes from v4.19 in order to make upstream process
easier.
Signed-off-by: Andrzej Perczak <linux@andrzejperczak.com>
When the target process is busy, incoming oneway transactions are
queued in the async_todo list. If the clients continue sending extra
oneway transactions while the target process is frozen, this queue can
become too large to accommodate new transactions. That's why binder
driver introduced ONEWAY_SPAM_DETECTION to detect this situation. It's
helpful to debug the async binder buffer exhausting issue, but the
issue itself isn't solved directly.
In real cases applications are designed to send oneway transactions
repeatedly, delivering updated inforamtion to the target process.
Typical examples are Wi-Fi signal strength and some real time sensor
data. Even if the apps might only care about the lastet information,
all outdated oneway transactions are still accumulated there until the
frozen process is thawed later. For this kind of situations, there's
no existing method to skip those outdated transactions and deliver the
latest one only.
This patch introduces a new transaction flag TF_UPDATE_TXN. To use it,
use apps can set this new flag along with TF_ONE_WAY. When such an
oneway transaction is to be queued into the async_todo list of a frozen
process, binder driver will check if any previous pending transactions
can be superseded by comparing their code, flags and target node. If
such an outdated pending transaction is found, the latest transaction
will supersede that outdated one. This effectively prevents the async
binder buffer running out and saves unnecessary binder read workloads.
Acked-by: Todd Kjos <tkjos@google.com>
Signed-off-by: Li Li <dualli@google.com>
Link: https://lore.kernel.org/r/20220526220018.3334775-2-dualli@chromium.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Bug: 231624308
Test: manually check async binder buffer size of frozen apps
Test: stress test with kernel 4.14/4.19/5.10/5.15
(cherry picked from commit 9864bb4801331daa48514face9d0f4861e4d485b
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc.git
char-misc-next)
Change-Id: I1c4bff1eda1ca15aaaad5bf696c8fc00be743176
Kernel code has a regular need to describe groups of members within a
structure usually when they need to be copied or initialized separately
from the rest of the surrounding structure. The generally accepted design
pattern in C is to use a named sub-struct:
struct foo {
int one;
struct {
int two;
int three, four;
} thing;
int five;
};
This would allow for traditional references and sizing:
memcpy(&dst.thing, &src.thing, sizeof(dst.thing));
However, doing this would mean that referencing struct members enclosed
by such named structs would always require including the sub-struct name
in identifiers:
do_something(dst.thing.three);
This has tended to be quite inflexible, especially when such groupings
need to be added to established code which causes huge naming churn.
Three workarounds exist in the kernel for this problem, and each have
other negative properties.
To avoid the naming churn, there is a design pattern of adding macro
aliases for the named struct:
#define f_three thing.three
This ends up polluting the global namespace, and makes it difficult to
search for identifiers.
Another common work-around in kernel code avoids the pollution by avoiding
the named struct entirely, instead identifying the group's boundaries using
either a pair of empty anonymous structs of a pair of zero-element arrays:
struct foo {
int one;
struct { } start;
int two;
int three, four;
struct { } finish;
int five;
};
struct foo {
int one;
int start[0];
int two;
int three, four;
int finish[0];
int five;
};
This allows code to avoid needing to use a sub-struct named for member
references within the surrounding structure, but loses the benefits of
being able to actually use such a struct, making it rather fragile. Using
these requires open-coded calculation of sizes and offsets. The efforts
made to avoid common mistakes include lots of comments, or adding various
BUILD_BUG_ON()s. Such code is left with no way for the compiler to reason
about the boundaries (e.g. the "start" object looks like it's 0 bytes
in length), making bounds checking depend on open-coded calculations:
if (length > offsetof(struct foo, finish) -
offsetof(struct foo, start))
return -EINVAL;
memcpy(&dst.start, &src.start, offsetof(struct foo, finish) -
offsetof(struct foo, start));
However, the vast majority of places in the kernel that operate on
groups of members do so without any identification of the grouping,
relying either on comments or implicit knowledge of the struct contents,
which is even harder for the compiler to reason about, and results in
even more fragile manual sizing, usually depending on member locations
outside of the region (e.g. to copy "two" and "three", use the start of
"four" to find the size):
BUILD_BUG_ON((offsetof(struct foo, four) <
offsetof(struct foo, two)) ||
(offsetof(struct foo, four) <
offsetof(struct foo, three));
if (length > offsetof(struct foo, four) -
offsetof(struct foo, two))
return -EINVAL;
memcpy(&dst.two, &src.two, length);
In order to have a regular programmatic way to describe a struct
region that can be used for references and sizing, can be examined for
bounds checking, avoids forcing the use of intermediate identifiers,
and avoids polluting the global namespace, introduce the struct_group()
macro. This macro wraps the member declarations to create an anonymous
union of an anonymous struct (no intermediate name) and a named struct
(for references and sizing):
struct foo {
int one;
struct_group(thing,
int two;
int three, four;
);
int five;
};
if (length > sizeof(src.thing))
return -EINVAL;
memcpy(&dst.thing, &src.thing, length);
do_something(dst.three);
There are some rare cases where the resulting struct_group() needs
attributes added, so struct_group_attr() is also introduced to allow
for specifying struct attributes (e.g. __align(x) or __packed).
Additionally, there are places where such declarations would like to
have the struct be tagged, so struct_group_tagged() is added.
Given there is a need for a handful of UAPI uses too, the underlying
__struct_group() macro has been defined in UAPI so it can be used there
too.
To avoid confusing scripts/kernel-doc, hide the macro from its struct
parsing.
Co-developed-by: Keith Packard <keithp@keithp.com>
Signed-off-by: Keith Packard <keithp@keithp.com>
Acked-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Link: https://lore.kernel.org/lkml/20210728023217.GC35706@embeddedor
Enhanced-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Link: https://lore.kernel.org/lkml/41183a98-bdb9-4ad6-7eab-5a7292a6df84@rasmusvillemoes.dk
Enhanced-by: Dan Williams <dan.j.williams@intel.com>
Link: https://lore.kernel.org/lkml/1d9a2e6df2a9a35b2cdd50a9a68cac5991e7e5f0.camel@intel.com
Enhanced-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://lore.kernel.org/lkml/YQKa76A6XuFqgM03@phenom.ffwll.local
Acked-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: UtsavBalar1231 <utsavbalar1231@gmail.com>
Change-Id: I227c72da06758c934013ec902fbf40613e033d1c
Signed-off-by: UtsavBalar1231 <utsavbalar1231@gmail.com>
There are many places where kernel code wants to have several different
typed trailing flexible arrays. This would normally be done with multiple
flexible arrays in a union, but since GCC and Clang don't (on the surface)
allow this, there have been many open-coded workarounds, usually involving
neighboring 0-element arrays at the end of a structure. For example,
instead of something like this:
struct thing {
...
union {
struct type1 foo[];
struct type2 bar[];
};
};
code works around the compiler with:
struct thing {
...
struct type1 foo[0];
struct type2 bar[];
};
Another case is when a flexible array is wanted as the single member
within a struct (which itself is usually in a union). For example, this
would be worked around as:
union many {
...
struct {
struct type3 baz[0];
};
};
These kinds of work-arounds cause problems with size checks against such
zero-element arrays (for example when building with -Warray-bounds and
-Wzero-length-bounds, and with the coming FORTIFY_SOURCE improvements),
so they must all be converted to "real" flexible arrays, avoiding warnings
like this:
fs/hpfs/anode.c: In function 'hpfs_add_sector_to_btree':
fs/hpfs/anode.c:209:27: warning: array subscript 0 is outside the bounds of an interior zero-length array 'struct bplus_internal_node[0]' [-Wzero-length-bounds]
209 | anode->btree.u.internal[0].down = cpu_to_le32(a);
| ~~~~~~~~~~~~~~~~~~~~~~~^~~
In file included from fs/hpfs/hpfs_fn.h:26,
from fs/hpfs/anode.c:10:
fs/hpfs/hpfs.h:412:32: note: while referencing 'internal'
412 | struct bplus_internal_node internal[0]; /* (internal) 2-word entries giving
| ^~~~~~~~
drivers/net/can/usb/etas_es58x/es58x_fd.c: In function 'es58x_fd_tx_can_msg':
drivers/net/can/usb/etas_es58x/es58x_fd.c:360:35: warning: array subscript 65535 is outside the bounds of an interior zero-length array 'u8[0]' {aka 'unsigned char[]'} [-Wzero-length-bounds]
360 | tx_can_msg = (typeof(tx_can_msg))&es58x_fd_urb_cmd->raw_msg[msg_len];
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
In file included from drivers/net/can/usb/etas_es58x/es58x_core.h:22,
from drivers/net/can/usb/etas_es58x/es58x_fd.c:17:
drivers/net/can/usb/etas_es58x/es58x_fd.h:231:6: note: while referencing 'raw_msg'
231 | u8 raw_msg[0];
| ^~~~~~~
However, it _is_ entirely possible to have one or more flexible arrays
in a struct or union: it just has to be in another struct. And since it
cannot be alone in a struct, such a struct must have at least 1 other
named member -- but that member can be zero sized. Wrap all this nonsense
into the new DECLARE_FLEX_ARRAY() in support of having flexible arrays
in unions (or alone in a struct).
As with struct_group(), since this is needed in UAPI headers as well,
implement the core there, with a non-UAPI wrapper.
Additionally update kernel-doc to understand its existence.
https://github.com/KSPP/linux/issues/137
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: "Gustavo A. R. Silva" <gustavoars@kernel.org>
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: UtsavBalar1231 <utsavbalar1231@gmail.com>
Change-Id: I8bbdf039c12beef2e4786595e5d728645a1b4803
Signed-off-by: UtsavBalar1231 <utsavbalar1231@gmail.com>
In case the user wants to stop controlling a uclamp constraint value
for a task, use the magic value -1 in sched_util_{min,max} with the
appropriate sched_flags (SCHED_FLAG_UTIL_CLAMP_{MIN,MAX}) to indicate
the reset.
The advantage over the 'additional flag' approach (i.e. introducing
SCHED_FLAG_UTIL_CLAMP_RESET) is that no additional flag has to be
exported via uapi. This avoids the need to document how this new flag
has be used in conjunction with the existing uclamp related flags.
The following subtle issue is fixed as well. When a uclamp constraint
value is set on a !user_defined uclamp_se it is currently first reset
and then set.
Fix this by AND'ing !user_defined with !SCHED_FLAG_UTIL_CLAMP which
stands for the 'sched class change' case.
The related condition 'if (uc_se->user_defined)' moved from
__setscheduler_uclamp() into uclamp_reset().
Signed-off-by: Dietmar Eggemann <dietmar.eggemann@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Yun Hsiang <hsiang023167@gmail.com>
Link: https://lkml.kernel.org/r/20201113113454.25868-1-dietmar.eggemann@arm.com
The SCHED_DEADLINE scheduling class provides an advanced and formal
model to define tasks requirements that can translate into proper
decisions for both task placements and frequencies selections. Other
classes have a more simplified model based on the POSIX concept of
priorities.
Such a simple priority based model however does not allow to exploit
most advanced features of the Linux scheduler like, for example, driving
frequencies selection via the schedutil cpufreq governor. However, also
for non SCHED_DEADLINE tasks, it's still interesting to define tasks
properties to support scheduler decisions.
Utilization clamping exposes to user-space a new set of per-task
attributes the scheduler can use as hints about the expected/required
utilization for a task. This allows to implement a "proactive" per-task
frequency control policy, a more advanced policy than the current one
based just on "passive" measured task utilization. For example, it's
possible to boost interactive tasks (e.g. to get better performance) or
cap background tasks (e.g. to be more energy/thermal efficient).
Introduce a new API to set utilization clamping values for a specified
task by extending sched_setattr(), a syscall which already allows to
define task specific properties for different scheduling classes. A new
pair of attributes allows to specify a minimum and maximum utilization
the scheduler can consider for a task.
Do that by validating the required clamp values before and then applying
the required changes using _the_ same pattern already in use for
__setscheduler(). This ensures that the task is re-enqueued with the new
clamp values.
Bug: 120440300
Signed-off-by: Patrick Bellasi <patrick.bellasi@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Alessio Balsini <balsini@android.com>
Cc: Dietmar Eggemann <dietmar.eggemann@arm.com>
Cc: Joel Fernandes <joelaf@google.com>
Cc: Juri Lelli <juri.lelli@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Morten Rasmussen <morten.rasmussen@arm.com>
Cc: Paul Turner <pjt@google.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Quentin Perret <quentin.perret@arm.com>
Cc: Rafael J . Wysocki <rafael.j.wysocki@intel.com>
Cc: Steve Muckle <smuckle@google.com>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Todd Kjos <tkjos@google.com>
Cc: Vincent Guittot <vincent.guittot@linaro.org>
Cc: Viresh Kumar <viresh.kumar@linaro.org>
Link: https://lkml.kernel.org/r/20190621084217.8167-7-patrick.bellasi@arm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
(cherry picked from commit a509a7cd79747074a2c018a45bbbc52d1f4aed44)
Signed-off-by: Qais Yousef <qais.yousef@arm.com>
Change-Id: I420e7ece5628bc639811a79654c35135a65bfd02
Signed-off-by: Quentin Perret <qperret@google.com>
Increase the total number of camera ID's supported.
Change-Id: Icf9cf2e48757d437a2b7dbbe618e886dc0203f6d
Signed-off-by: Om Parkash <quic_oparkash@quicinc.com>
[ Upstream commit e70a3263a7eed768d5f947b8f2aff8d2a79c9d97 ]
Currently, data[5..7] of struct can_frame, when used as a CAN error
frame, are defined as being "controller specific". Device specific
behaviours are problematic because it prevents someone from writing
code which is portable between devices.
As a matter of fact, data[5] is never used, data[6] is always used to
report TX error counter and data[7] is always used to report RX error
counter. can-utils also relies on this.
This patch updates the comment in the uapi header to specify that
data[5] is reserved (and thus should not be used) and that data[6..7]
are used for error counters.
Fixes: 0d66548a10 ("[CAN]: Add PF_CAN core module")
Link: https://lore.kernel.org/all/20220719143550.3681-11-mailhol.vincent@wanadoo.fr
Signed-off-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
In general, as of now, in FUSE, direct writes on the same file are
serialized over inode lock i.e we hold inode lock for the full duration
of the write request. I could not found in fuse code a comment which
clearly explains why this exclusive lock is taken for direct writes.
Our guess is some USER space fuse implementations might be relying
on this lock for seralization and also it protects for the issues
arising due to file size assumption or write failures. This patch
relaxes this exclusive lock in some cases of direct writes.
With these changes, we allows non-extending parallel direct writes
on the same file with the help of a flag called FOPEN_PARALLEL_WRITES.
If this flag is set on the file (flag is passed from libfuse to fuse
kernel as part of file open/create), we do not take exclusive lock instead
use shared lock so that all non-extending writes can run in parallel.
Best practise would be to enable parallel direct writes of all kinds
including extending writes as well but we see some issues such as
when one write completes and other fails, how we should truncate(if
needed) the file if underlying file system does not support holes
(For file systems which supports holes, there might be a possibility
of enabling parallel writes for all cases).
FUSE implementations which rely on this inode lock for serialisation
can continue to do so and this is default behaviour i.e no parallel
direct writes.
Signed-off-by: Dharmendra Singh <dsingh@ddn.com>
[cyberknight777: backport and adapt to 4.14 fuse implementation]
Signed-off-by: Cyber Knight <cyberknight755@gmail.com>
When remapping an anonymous, private mapping, if MREMAP_DONTUNMAP is set,
the source mapping will not be removed. The remap operation will be
performed as it would have been normally by moving over the page tables to
the new mapping. The old vma will have any locked flags cleared, have no
pagetables, and any userfaultfds that were watching that range will
continue watching it.
For a mapping that is shared or not anonymous, MREMAP_DONTUNMAP will cause
the mremap() call to fail. Because MREMAP_DONTUNMAP always results in
moving a VMA you MUST use the MREMAP_MAYMOVE flag, it's not possible to
resize a VMA while also moving with MREMAP_DONTUNMAP so old_len must
always be equal to the new_len otherwise it will return -EINVAL.
We hope to use this in Chrome OS where with userfaultfd we could write an
anonymous mapping to disk without having to STOP the process or worry
about VMA permission changes.
This feature also has a use case in Android, Lokesh Gidra has said that
"As part of using userfaultfd for GC, We'll have to move the physical
pages of the java heap to a separate location. For this purpose mremap
will be used. Without the MREMAP_DONTUNMAP flag, when I mremap the java
heap, its virtual mapping will be removed as well. Therefore, we'll
require performing mmap immediately after. This is not only time
consuming but also opens a time window where a native thread may call mmap
and reserve the java heap's address range for its own usage. This flag
solves the problem."
[bgeffon@google.com: v6]
Link: http://lkml.kernel.org/r/20200218173221.237674-1-bgeffon@google.com
[bgeffon@google.com: v7]
Link: http://lkml.kernel.org/r/20200221174248.244748-1-bgeffon@google.com
Signed-off-by: Brian Geffon <bgeffon@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Tested-by: Lokesh Gidra <lokeshgidra@google.com>
Reviewed-by: Minchan Kim <minchan@kernel.org>
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: "Michael S . Tsirkin" <mst@redhat.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Will Deacon <will@kernel.org>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Sonny Rao <sonnyrao@google.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Joel Fernandes <joel@joelfernandes.org>
Cc: Yu Zhao <yuzhao@google.com>
Cc: Jesse Barnes <jsbarnes@google.com>
Cc: Nathan Chancellor <natechancellor@gmail.com>
Cc: Florian Weimer <fweimer@redhat.com>
Link: http://lkml.kernel.org/r/20200207201856.46070-1-bgeffon@google.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Park Ju Hyung <qkrwngud825@gmail.com>
Signed-off-by: Alex Winkowski <dereference23@outlook.com>
