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Linux kernel
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several of them using the Restructured Text markup notation.
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the problems which may result by upgrading your kernel.
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Pull copy_struct_from_user() helper from Christian Brauner:
"This contains the copy_struct_from_user() helper which got split out
from the openat2() patchset. It is a generic interface designed to
copy a struct from userspace.
The helper will be especially useful for structs versioned by size of
which we have quite a few. This allows for backwards compatibility,
i.e. an extended struct can be passed to an older kernel, or a legacy
struct can be passed to a newer kernel. For the first case (extended
struct, older kernel) the new fields in an extended struct can be set
to zero and the struct safely passed to an older kernel.
The most obvious benefit is that this helper lets us get rid of
duplicate code present in at least sched_setattr(), perf_event_open(),
and clone3(). More importantly it will also help to ensure that users
implementing versioning-by-size end up with the same core semantics.
This point is especially crucial since we have at least one case where
versioning-by-size is used but with slighly different semantics:
sched_setattr(), perf_event_open(), and clone3() all do do similar
checks to copy_struct_from_user() while rt_sigprocmask(2) always
rejects differently-sized struct arguments.
With this pull request we also switch over sched_setattr(),
perf_event_open(), and clone3() to use the new helper"
* tag 'copy-struct-from-user-v5.4-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux:
usercopy: Add parentheses around assignment in test_copy_struct_from_user
perf_event_open: switch to copy_struct_from_user()
sched_setattr: switch to copy_struct_from_user()
clone3: switch to copy_struct_from_user()
lib: introduce copy_struct_from_user() helper
Pull clone3/pidfd fixes from Christian Brauner:
"This contains a couple of fixes:
- Fix pidfd selftest compilation (Shuah Kahn)
Due to a false linking instruction in the Makefile compilation for
the pidfd selftests would fail on some systems.
- Fix compilation for glibc on RISC-V systems (Seth Forshee)
In some scenarios linux/uapi/linux/sched.h is included where
__ASSEMBLY__ is defined causing a build failure because struct
clone_args was not guarded by an #ifndef __ASSEMBLY__.
- Add missing clone3() and struct clone_args kernel-doc (Christian Brauner)
clone3() and struct clone_args were missing kernel-docs. (The goal
is to use kernel-doc for any function or type where it's worth it.)
For struct clone_args this also contains a comment about the fact
that it's versioned by size"
* tag 'for-linus-20191003' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux:
sched: add kernel-doc for struct clone_args
fork: add kernel-doc for clone3
selftests: pidfd: Fix undefined reference to pthread_create()
sched: Add __ASSEMBLY__ guards around struct clone_args
Clang warns:
lib/test_user_copy.c:96:10: warning: using the result of an assignment
as a condition without parentheses [-Wparentheses]
if (ret |= test(umem_src == NULL, "kmalloc failed"))
~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
lib/test_user_copy.c:96:10: note: place parentheses around the
assignment to silence this warning
if (ret |= test(umem_src == NULL, "kmalloc failed"))
^
( )
lib/test_user_copy.c:96:10: note: use '!=' to turn this compound
assignment into an inequality comparison
if (ret |= test(umem_src == NULL, "kmalloc failed"))
^~
!=
Add the parentheses as it suggests because this is intentional.
Fixes: f5a1a536fa14 ("lib: introduce copy_struct_from_user() helper")
Link: https://github.com/ClangBuiltLinux/linux/issues/731
Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
Acked-by: Aleksa Sarai <cyphar@cyphar.com>
Acked-by: Christian Brauner <christian.brauner@ubuntu.com>
Link: https://lore.kernel.org/r/20191003171121.2723619-1-natechancellor@gmail.com
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
Pull drm fixes from Dave Airlie:
"Been offline for 3 days, got back and had some fixes queued up.
Nothing too major, the i915 dp-mst fix is important, and amdgpu has a
bulk move speedup fix and some regressions, but nothing too insane for
an rc2 pull. The intel fixes are also 2 weeks worth, they missed the
boat last week.
core:
- writeback fixes
i915:
- Fix DP-MST crtc_mask
- Fix dsc dpp calculations
- Fix g4x sprite scaling stride check with GTT remapping
- Fix concurrence on cases where requests where getting retired at
same time as resubmitted to HW
- Fix gen9 display resolutions by setting the right max plane width
- Fix GPU hang on preemption
- Mark contents as dirty on a write fault. This was breaking cursor
sprite with dumb buffers.
komeda:
- memory leak fix
tilcdc:
- include fix
amdgpu:
- Enable bulk moves
- Power metrics fixes for Navi
- Fix S4 regression
- Add query for tcc disabled mask
- Fix several leaks in error paths
- randconfig fixes
- clang fixes"
* tag 'drm-fixes-2019-10-04' of git://anongit.freedesktop.org/drm/drm: (21 commits)
Revert "drm/i915: Fix DP-MST crtc_mask"
drm/omap: fix max fclk divider for omap36xx
drm/i915: Fix g4x sprite scaling stride check with GTT remapping
drm/i915/dp: Fix dsc bpp calculations, v5.
drm/amd/display: fix dcn21 Makefile for clang
drm/amd/display: hide an unused variable
drm/amdgpu: display_mode_vba_21: remove uint typedef
drm/amdgpu: hide another #warning
drm/amdgpu: make pmu support optional, again
drm/amd/display: memory leak
drm/amdgpu: fix multiple memory leaks in acp_hw_init
drm/amdgpu: return tcc_disabled_mask to userspace
drm/amdgpu: don't increment vram lost if we are in hibernation
Revert "drm/amdgpu: disable stutter mode for renoir"
drm/amd/powerplay: add sensor lock support for smu
drm/amd/powerplay: change metrics update period from 1ms to 100ms
drm/amdgpu: revert "disable bulk moves for now"
drm/tilcdc: include linux/pinctrl/consumer.h again
drm/komeda: prevent memory leak in komeda_wb_connector_add
drm: Clear the fence pointer when writeback job signaled
...
Add kernel-doc for struct clone_args for the clone3() syscall.
Link: https://lore.kernel.org/r/20191001114701.24661-3-christian.brauner@ubuntu.com
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
Switch perf_event_open() syscall from it's own copying
struct perf_event_attr from userspace to the new dedicated
copy_struct_from_user() helper.
The change is very straightforward, and helps unify the syscall
interface for struct-from-userspace syscalls.
Signed-off-by: Aleksa Sarai <cyphar@cyphar.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Christian Brauner <christian.brauner@ubuntu.com>
[christian.brauner@ubuntu.com: improve commit message]
Link: https://lore.kernel.org/r/20191001011055.19283-5-cyphar@cyphar.com
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
Pull block fixes from Jens Axboe:
- Mandate timespec64 for the io_uring timeout ABI (Arnd)
- Set of NVMe changes via Sagi:
- controller removal race fix from Balbir
- quirk additions from Gabriel and Jian-Hong
- nvme-pci power state save fix from Mario
- Add 64bit user commands (for 64bit registers) from Marta
- nvme-rdma/nvme-tcp fixes from Max, Mark and Me
- Minor cleanups and nits from James, Dan and John
- Two s390 dasd fixes (Jan, Stefan)
- Have loop change block size in DIO mode (Martijn)
- paride pg header ifdef guard (Masahiro)
- Two blk-mq queue scheduler tweaks, fixing an ordering issue on zoned
devices and suboptimal performance on others (Ming)
* tag 'for-linus-2019-10-03' of git://git.kernel.dk/linux-block: (22 commits)
block: sed-opal: fix sparse warning: convert __be64 data
block: sed-opal: fix sparse warning: obsolete array init.
block: pg: add header include guard
Revert "s390/dasd: Add discard support for ESE volumes"
s390/dasd: Fix error handling during online processing
io_uring: use __kernel_timespec in timeout ABI
loop: change queue block size to match when using DIO
blk-mq: apply normal plugging for HDD
blk-mq: honor IO scheduler for multiqueue devices
nvme-rdma: fix possible use-after-free in connect timeout
nvme: Move ctrl sqsize to generic space
nvme: Add ctrl attributes for queue_count and sqsize
nvme: allow 64-bit results in passthru commands
nvme: Add quirk for Kingston NVME SSD running FW E8FK11.T
nvmet-tcp: remove superflous check on request sgl
Added QUIRKs for ADATA XPG SX8200 Pro 512GB
nvme-rdma: Fix max_hw_sectors calculation
nvme: fix an error code in nvme_init_subsystem()
nvme-pci: Save PCI state before putting drive into deepest state
nvme-tcp: fix wrong stop condition in io_work
...
- Fix DP-MST crtc_mask
- Fix dsc dpp calculations
- Fix g4x sprite scaling stride check with GTT remapping
Signed-off-by: Dave Airlie <airlied@redhat.com>
From: Rodrigo Vivi <rodrigo.vivi@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191003193051.GA26421@intel.com
Add kernel-doc for the clone3() syscall.
Link: https://lore.kernel.org/r/20191001114701.24661-2-christian.brauner@ubuntu.com
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
Switch sched_setattr() syscall from it's own copying struct sched_attr
from userspace to the new dedicated copy_struct_from_user() helper.
The change is very straightforward, and helps unify the syscall
interface for struct-from-userspace syscalls. Ideally we could also
unify sched_getattr(2)-style syscalls as well, but unfortunately the
correct semantics for such syscalls are much less clear (see [1] for
more detail). In future we could come up with a more sane idea for how
the syscall interface should look.
[1]: commit 1251201c0d34 ("sched/core: Fix uclamp ABI bug, clean up and
robustify sched_read_attr() ABI logic and code")
Signed-off-by: Aleksa Sarai <cyphar@cyphar.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Christian Brauner <christian.brauner@ubuntu.com>
[christian.brauner@ubuntu.com: improve commit message]
Link: https://lore.kernel.org/r/20191001011055.19283-4-cyphar@cyphar.com
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
Today, put_compat_statfs64() disallows nearly any field value over
2^32 if f_bsize is only 32 bits, but that makes no sense.
compat_statfs64 is there for the explicit purpose of providing 64-bit
fields for f_files, f_ffree, etc. And f_bsize is always only 32 bits.
As a result, 32-bit userspace gets -EOVERFLOW for i.e. large file
counts even with -D_FILE_OFFSET_BITS=64 set.
In reality, only f_bsize and f_frsize can legitimately overflow
(fields like f_type and f_namelen should never be large), so test
only those fields.
This bug was discussed at length some time ago, and this is the proposal
Al suggested at https://lkml.org/lkml/2018/8/6/640. It seemed to get
dropped amid the discussion of other related changes, but this
part seems obviously correct on its own, so I've picked it up and
sent it, for expediency.
Fixes: 64d2ab32efe3 ("vfs: fix put_compat_statfs64() does not handle errors")
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
sparse warns about incorrect type when using __be64 data.
It is not being converted to CPU-endian but it should be.
Fixes these sparse warnings:
../block/sed-opal.c:375:20: warning: incorrect type in assignment (different base types)
../block/sed-opal.c:375:20: expected unsigned long long [usertype] align
../block/sed-opal.c:375:20: got restricted __be64 const [usertype] alignment_granularity
../block/sed-opal.c:376:25: warning: incorrect type in assignment (different base types)
../block/sed-opal.c:376:25: expected unsigned long long [usertype] lowest_lba
../block/sed-opal.c:376:25: got restricted __be64 const [usertype] lowest_aligned_lba
Fixes: 455a7b238cd6 ("block: Add Sed-opal library")
Cc: Scott Bauer <scott.bauer@intel.com>
Cc: Rafael Antognolli <rafael.antognolli@intel.com>
Cc: linux-block@vger.kernel.org
Reviewed-by: Jon Derrick <jonathan.derrick@intel.com>
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
- One include fix for tilcdc
- A clock fix for OMAP
- A memory leak fix for Komeda
- Some fixes for resources cleanups with writeback
Signed-off-by: Dave Airlie <airlied@redhat.com>
From: Maxime Ripard <mripard@kernel.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20191003081031.oykms5fg4tijvdri@gilmour
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