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git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux
Pull btrfs fix from David Sterba:
"A fix for an older bug that has started to show up during testing
(because of an updated test for rename exchange).
It's an in-memory corruption caused by local variable leaking out of
the function scope"
* tag 'for-5.4-rc7-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux:
Btrfs: fix log context list corruption after rename exchange operation
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On a system without KVM_COMPAT, we prevent IOCTLs from being issued
by a compat task. Although this prevents most silly things from
happening, it can still confuse a 32bit userspace that is able
to open the kvm device (the qemu test suite seems to be pretty
mad with this behaviour).
Take a more radical approach and return a -ENODEV to the compat
task.
Reported-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
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When applying commit 7a5ee6edb42e ("KVM: X86: Fix initialization of MSR
lists"), it forgot to reset the three MSR lists number varialbes to 0
while removing the useless conditionals.
Fixes: 7a5ee6edb42e (KVM: X86: Fix initialization of MSR lists)
Signed-off-by: Xiaoyao Li <xiaoyao.li@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
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Glibc-2.30 gained gettid() wrapper, selftests fail to compile:
lib/assert.c:58:14: error: static declaration of ‘gettid’ follows non-static declaration
58 | static pid_t gettid(void)
| ^~~~~~
In file included from /usr/include/unistd.h:1170,
from include/test_util.h:18,
from lib/assert.c:10:
/usr/include/bits/unistd_ext.h:34:16: note: previous declaration of ‘gettid’ was here
34 | extern __pid_t gettid (void) __THROW;
| ^~~~~~
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
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If a huge page is recovered (and becomes no executable) while another
thread is executing it, the resulting contention on mmu_lock can cause
latency spikes. Disabling recovery for PREEMPT_RT kernels fixes this
issue.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
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The datasheet of V3s (and various other chips) wrote
that TCON0_DCLK_DIV can be >= 1 if only dclk is used,
and must >= 6 if dclk1 or dclk2 is used. As currently
neither dclk1 nor dclk2 is used (no writes to these
bits), let's set minimal division to 1.
If this minimal division is 6, some common dot clock
frequencies can't be produced (e.g. 30MHz will not be
possible and will fallback to 25MHz), which is
obviously not an expected behaviour.
Signed-off-by: Yunhao Tian <t123yh@outlook.com>
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Link: https://lore.kernel.org/linux-arm-kernel/MN2PR08MB57905AD8A00C08DA219377C989760@MN2PR08MB5790.namprd08.prod.outlook.com/
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When the CC variable contains quotes, e.g. when using
ccache (make CC="ccache <compiler>"), this script always
fails, so CONFIG_RELR is never enabled, even when the
toolchain supports this feature. Removing the /dev/null
redirect and invoking the script manually shows the issue:
$ CC='/usr/bin/ccache clang' ./scripts/tools-support-relr.sh
./scripts/tools-support-relr.sh: 7: ./scripts/tools-support-relr.sh: /usr/bin/ccache clang: not found
Fix this by un-quoting the variables.
Before:
$ make ARCH=arm64 CC='/usr/bin/ccache clang' LD=ld.lld \
NM=llvm-nm OBJCOPY=llvm-objcopy defconfig
$ grep RELR .config
CONFIG_ARCH_HAS_RELR=y
With this change:
$ make ARCH=arm64 CC='/usr/bin/ccache clang' LD=ld.lld \
NM=llvm-nm OBJCOPY=llvm-objcopy defconfig
$ grep RELR .config
CONFIG_TOOLS_SUPPORT_RELR=y
CONFIG_ARCH_HAS_RELR=y
CONFIG_RELR=y
Fixes: 5cf896fb6be3 ("arm64: Add support for relocating the kernel with RELR relocations")
Reported-by: Dmitry Golovin <dima@golovin.in>
Reviewed-by: Nathan Chancellor <natechancellor@gmail.com>
Reviewed-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Link: https://github.com/ClangBuiltLinux/linux/issues/769
Cc: Peter Collingbourne <pcc@google.com>
Signed-off-by: Ilie Halip <ilie.halip@gmail.com>
Signed-off-by: Will Deacon <will@kernel.org>
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If the nullity check for `substream->runtime` is outside of the lock
region, it is possible to have a null runtime in the critical section
if snd_pcm_detach_substream is called right before the lock.
Signed-off-by: paulhsia <paulhsia@chromium.org>
Link: https://lore.kernel.org/r/20191112171715.128727-2-paulhsia@chromium.org
Signed-off-by: Takashi Iwai <tiwai@suse.de>
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While output urb's snd_complete_urb() is executing, calling
prepare_outbound_urb() may cause endpoint stopped before
prepare_outbound_urb() returns and result in next urb submitted
to stopped endpoint. usb-audio driver cannot re-use it afterwards as
the urb is still hold by usb stack.
This change checks EP_FLAG_RUNNING flag after prepare_outbound_urb() again
to let snd_complete_urb() know the endpoint already stopped and does not
submit next urb. Below kind of error will be fixed:
[ 213.153103] usb 1-2: timeout: still 1 active urbs on EP #1
[ 213.164121] usb 1-2: cannot submit urb 0, error -16: unknown error
Signed-off-by: Henry Lin <henryl@nvidia.com>
Cc: <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/20191113021420.13377-1-henryl@nvidia.com
Signed-off-by: Takashi Iwai <tiwai@suse.de>
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The device md->input is used after it is released. Setting the device
data to NULL is unnecessary as the device is never used again. Instead,
md->input should be assigned NULL to avoid accessing the freed memory
accidently. Besides, checking md->si against NULL is superfluous as it
points to a variable address, which cannot be NULL.
Signed-off-by: Pan Bian <bianpan2016@163.com>
Link: https://lore.kernel.org/r/1572936379-6423-1-git-send-email-bianpan2016@163.com
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
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The driver for F54 just polls the status and doesn't even have a IRQ
handler registered. Make sure to disable all F54 IRQs, so we don't crash
the kernel on a nonexistent handler.
Signed-off-by: Lucas Stach <l.stach@pengutronix.de>
Link: https://lore.kernel.org/r/20191105114402.6009-1-l.stach@pengutronix.de
Cc: stable@vger.kernel.org
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
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This went into staging in rc7. It turns out that was a mistake, and
apparently it wasn't even supposed to go there at all, but be introduced
as a regular filesystem.
We don't try to sneak in whole new filesystems this late in the rc, just
delete the whole thing, and it can be re-introduced as a proper patch
with proper acks from actual filesystem people instead of some odd
late-rc staging back-door.
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Pull kvm fixes from Paolo Bonzini:
"Fix unwinding of KVM_CREATE_VM failure, VT-d posted interrupts,
DAX/ZONE_DEVICE, and module unload/reload"
* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
KVM: MMU: Do not treat ZONE_DEVICE pages as being reserved
KVM: VMX: Introduce pi_is_pir_empty() helper
KVM: VMX: Do not change PID.NDST when loading a blocked vCPU
KVM: VMX: Consider PID.PIR to determine if vCPU has pending interrupts
KVM: VMX: Fix comment to specify PID.ON instead of PIR.ON
KVM: X86: Fix initialization of MSR lists
KVM: fix placement of refcount initialization
KVM: Fix NULL-ptr deref after kvm_create_vm fails
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drm-intel-fixes
gvt-fixes-2019-11-12
- Fix dmabuf reference drop (Pan)
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
From: Zhenyu Wang <zhenyuw@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191112061834.GN4196@zhen-hp.sh.intel.com
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Since CNP it's possible for rawclk to have two different values, 19.2
and 24 MHz. If the value indicated by SFUSE_STRAP register is different
from the power on default for PCH_RAWCLK_FREQ, we'll end up having a
mismatch between the rawclk hardware and software states after
suspend/resume. On previous platforms this used to work by accident,
because the power on defaults worked just fine.
Update the rawclk also on resume. The natural place to do this would be
intel_modeset_init_hw(), however VLV/CHV need it done before
intel_power_domains_init_hw(). Thus put it there even if it feels
slightly out of place.
v2: Call intel_update_rawclck() in intel_power_domains_init_hw() for all
platforms (Ville).
Reported-by: Shawn Lee <shawn.c.lee@intel.com>
Cc: Shawn Lee <shawn.c.lee@intel.com>
Cc: Ville Syrjala <ville.syrjala@linux.intel.com>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Tested-by: Shawn Lee <shawn.c.lee@intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191101142024.13877-1-jani.nikula@intel.com
(cherry picked from commit 59ed05ccdded5eb18ce012eff3d01798ac8535fa)
Cc: <stable@vger.kernel.org> # v4.15+
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
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git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 TSX Async Abort and iTLB Multihit mitigations from Thomas Gleixner:
"The performance deterioration departement is not proud at all of
presenting the seventh installment of speculation mitigations and
hardware misfeature workarounds:
1) TSX Async Abort (TAA) - 'The Annoying Affair'
TAA is a hardware vulnerability that allows unprivileged
speculative access to data which is available in various CPU
internal buffers by using asynchronous aborts within an Intel TSX
transactional region.
The mitigation depends on a microcode update providing a new MSR
which allows to disable TSX in the CPU. CPUs which have no
microcode update can be mitigated by disabling TSX in the BIOS if
the BIOS provides a tunable.
Newer CPUs will have a bit set which indicates that the CPU is not
vulnerable, but the MSR to disable TSX will be available
nevertheless as it is an architected MSR. That means the kernel
provides the ability to disable TSX on the kernel command line,
which is useful as TSX is a truly useful mechanism to accelerate
side channel attacks of all sorts.
2) iITLB Multihit (NX) - 'No eXcuses'
iTLB Multihit is an erratum where some Intel processors may incur
a machine check error, possibly resulting in an unrecoverable CPU
lockup, when an instruction fetch hits multiple entries in the
instruction TLB. This can occur when the page size is changed
along with either the physical address or cache type. A malicious
guest running on a virtualized system can exploit this erratum to
perform a denial of service attack.
The workaround is that KVM marks huge pages in the extended page
tables as not executable (NX). If the guest attempts to execute in
such a page, the page is broken down into 4k pages which are
marked executable. The workaround comes with a mechanism to
recover these shattered huge pages over time.
Both issues come with full documentation in the hardware
vulnerabilities section of the Linux kernel user's and administrator's
guide.
Thanks to all patch authors and reviewers who had the extraordinary
priviledge to be exposed to this nuisance.
Special thanks to Borislav Petkov for polishing the final TAA patch
set and to Paolo Bonzini for shepherding the KVM iTLB workarounds and
providing also the backports to stable kernels for those!"
* 'x86-pti-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/speculation/taa: Fix printing of TAA_MSG_SMT on IBRS_ALL CPUs
Documentation: Add ITLB_MULTIHIT documentation
kvm: x86: mmu: Recovery of shattered NX large pages
kvm: Add helper function for creating VM worker threads
kvm: mmu: ITLB_MULTIHIT mitigation
cpu/speculation: Uninline and export CPU mitigations helpers
x86/cpu: Add Tremont to the cpu vulnerability whitelist
x86/bugs: Add ITLB_MULTIHIT bug infrastructure
x86/tsx: Add config options to set tsx=on|off|auto
x86/speculation/taa: Add documentation for TSX Async Abort
x86/tsx: Add "auto" option to the tsx= cmdline parameter
kvm/x86: Export MDS_NO=0 to guests when TSX is enabled
x86/speculation/taa: Add sysfs reporting for TSX Async Abort
x86/speculation/taa: Add mitigation for TSX Async Abort
x86/cpu: Add a "tsx=" cmdline option with TSX disabled by default
x86/cpu: Add a helper function x86_read_arch_cap_msr()
x86/msr: Add the IA32_TSX_CTRL MSR
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__bio_try_merge_page() may merge a page to bio without bio_full() check
and cause bi_size overflow.
The overflow typically ends up with sd_init_command() warning on zero
segment request with call trace like this:
------------[ cut here ]------------
WARNING: CPU: 2 PID: 1986 at drivers/scsi/scsi_lib.c:1025 scsi_init_io+0x156/0x180
CPU: 2 PID: 1986 Comm: kworker/2:1H Kdump: loaded Not tainted 5.4.0-rc7 #1
Workqueue: kblockd blk_mq_run_work_fn
RIP: 0010:scsi_init_io+0x156/0x180
RSP: 0018:ffffa11487663bf0 EFLAGS: 00010246
RAX: 00000000002be0a0 RBX: ffff8e6e9ff30118 RCX: 0000000000000000
RDX: 00000000ffffffe1 RSI: 0000000000000000 RDI: ffff8e6e9ff30118
RBP: ffffa11487663c18 R08: ffffa11487663d28 R09: ffff8e6e9ff30150
R10: 0000000000000001 R11: 0000000000000000 R12: ffff8e6e9ff30000
R13: 0000000000000001 R14: ffff8e74a1cf1800 R15: ffff8e6e9ff30000
FS: 0000000000000000(0000) GS:ffff8e6ea7680000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fff18cf0fe8 CR3: 0000000659f0a001 CR4: 00000000001606e0
Call Trace:
sd_init_command+0x326/0xb40 [sd_mod]
scsi_queue_rq+0x502/0xaa0
? blk_mq_get_driver_tag+0xe7/0x120
blk_mq_dispatch_rq_list+0x256/0x5a0
? elv_rb_del+0x24/0x30
? deadline_remove_request+0x7b/0xc0
blk_mq_do_dispatch_sched+0xa3/0x140
blk_mq_sched_dispatch_requests+0xfb/0x170
__blk_mq_run_hw_queue+0x81/0x130
blk_mq_run_work_fn+0x1b/0x20
process_one_work+0x179/0x390
worker_thread+0x4f/0x3e0
kthread+0x105/0x140
? max_active_store+0x80/0x80
? kthread_bind+0x20/0x20
ret_from_fork+0x35/0x40
---[ end trace f9036abf5af4a4d3 ]---
blk_update_request: I/O error, dev sdd, sector 2875552 op 0x1:(WRITE) flags 0x0 phys_seg 0 prio class 0
XFS (sdd1): writeback error on sector 2875552
__bio_try_merge_page() should check the overflow before actually doing
merge.
Fixes: 07173c3ec276c ("block: enable multipage bvecs")
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Jun'ichi Nomura <j-nomura@ce.jp.nec.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
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Explicitly exempt ZONE_DEVICE pages from kvm_is_reserved_pfn() and
instead manually handle ZONE_DEVICE on a case-by-case basis. For things
like page refcounts, KVM needs to treat ZONE_DEVICE pages like normal
pages, e.g. put pages grabbed via gup(). But for flows such as setting
A/D bits or shifting refcounts for transparent huge pages, KVM needs to
to avoid processing ZONE_DEVICE pages as the flows in question lack the
underlying machinery for proper handling of ZONE_DEVICE pages.
This fixes a hang reported by Adam Borowski[*] in dev_pagemap_cleanup()
when running a KVM guest backed with /dev/dax memory, as KVM straight up
doesn't put any references to ZONE_DEVICE pages acquired by gup().
Note, Dan Williams proposed an alternative solution of doing put_page()
on ZONE_DEVICE pages immediately after gup() in order to simplify the
auditing needed to ensure is_zone_device_page() is called if and only if
the backing device is pinned (via gup()). But that approach would break
kvm_vcpu_{un}map() as KVM requires the page to be pinned from map() 'til
unmap() when accessing guest memory, unlike KVM's secondary MMU, which
coordinates with mmu_notifier invalidations to avoid creating stale
page references, i.e. doesn't rely on pages being pinned.
[*] http://lkml.kernel.org/r/20190919115547.GA17963@angband.pl
Reported-by: Adam Borowski <kilobyte@angband.pl>
Analyzed-by: David Hildenbrand <david@redhat.com>
Acked-by: Dan Williams <dan.j.williams@intel.com>
Cc: stable@vger.kernel.org
Fixes: 3565fce3a659 ("mm, x86: get_user_pages() for dax mappings")
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
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Streamline the PID.PIR check and change its call sites to use
the newly added helper.
Suggested-by: Liran Alon <liran.alon@oracle.com>
Signed-off-by: Joao Martins <joao.m.martins@oracle.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
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When vCPU enters block phase, pi_pre_block() inserts vCPU to a per pCPU
linked list of all vCPUs that are blocked on this pCPU. Afterwards, it
changes PID.NV to POSTED_INTR_WAKEUP_VECTOR which its handler
(wakeup_handler()) is responsible to kick (unblock) any vCPU on that
linked list that now has pending posted interrupts.
While vCPU is blocked (in kvm_vcpu_block()), it may be preempted which
will cause vmx_vcpu_pi_put() to set PID.SN. If later the vCPU will be
scheduled to run on a different pCPU, vmx_vcpu_pi_load() will clear
PID.SN but will also *overwrite PID.NDST to this different pCPU*.
Instead of keeping it with original pCPU which vCPU had entered block
phase on.
This results in an issue because when a posted interrupt is delivered, as
the wakeup_handler() will be executed and fail to find blocked vCPU on
its per pCPU linked list of all vCPUs that are blocked on this pCPU.
Which is due to the vCPU being placed on a *different* per pCPU
linked list i.e. the original pCPU in which it entered block phase.
The regression is introduced by commit c112b5f50232 ("KVM: x86:
Recompute PID.ON when clearing PID.SN"). Therefore, partially revert
it and reintroduce the condition in vmx_vcpu_pi_load() responsible for
avoiding changing PID.NDST when loading a blocked vCPU.
Fixes: c112b5f50232 ("KVM: x86: Recompute PID.ON when clearing PID.SN")
Tested-by: Nathan Ni <nathan.ni@oracle.com>
Co-developed-by: Liran Alon <liran.alon@oracle.com>
Signed-off-by: Liran Alon <liran.alon@oracle.com>
Signed-off-by: Joao Martins <joao.m.martins@oracle.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
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Commit 17e433b54393 ("KVM: Fix leak vCPU's VMCS value into other pCPU")
introduced vmx_dy_apicv_has_pending_interrupt() in order to determine
if a vCPU have a pending posted interrupt. This routine is used by
kvm_vcpu_on_spin() when searching for a a new runnable vCPU to schedule
on pCPU instead of a vCPU doing busy loop.
vmx_dy_apicv_has_pending_interrupt() determines if a
vCPU has a pending posted interrupt solely based on PID.ON. However,
when a vCPU is preempted, vmx_vcpu_pi_put() sets PID.SN which cause
raised posted interrupts to only set bit in PID.PIR without setting
PID.ON (and without sending notification vector), as depicted in VT-d
manual section 5.2.3 "Interrupt-Posting Hardware Operation".
Therefore, checking PID.ON is insufficient to determine if a vCPU has
pending posted interrupts and instead we should also check if there is
some bit set on PID.PIR if PID.SN=1.
Fixes: 17e433b54393 ("KVM: Fix leak vCPU's VMCS value into other pCPU")
Reviewed-by: Jagannathan Raman <jag.raman@oracle.com>
Co-developed-by: Liran Alon <liran.alon@oracle.com>
Signed-off-by: Liran Alon <liran.alon@oracle.com>
Signed-off-by: Joao Martins <joao.m.martins@oracle.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
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The Outstanding Notification (ON) bit is part of the Posted Interrupt
Descriptor (PID) as opposed to the Posted Interrupts Register (PIR).
The latter is a bitmap for pending vectors.
Reviewed-by: Joao Martins <joao.m.martins@oracle.com>
Signed-off-by: Liran Alon <liran.alon@oracle.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
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The three MSR lists(msrs_to_save[], emulated_msrs[] and
msr_based_features[]) are global arrays of kvm.ko, which are
adjusted (copy supported MSRs forward to override the unsupported MSRs)
when insmod kvm-{intel,amd}.ko, but it doesn't reset these three arrays
to their initial value when rmmod kvm-{intel,amd}.ko. Thus, at the next
installation, kvm-{intel,amd}.ko will do operations on the modified
arrays with some MSRs lost and some MSRs duplicated.
So define three constant arrays to hold the initial MSR lists and
initialize msrs_to_save[], emulated_msrs[] and msr_based_features[]
based on the constant arrays.
Cc: stable@vger.kernel.org
Reviewed-by: Xiaoyao Li <xiaoyao.li@intel.com>
Signed-off-by: Chenyi Qiang <chenyi.qiang@intel.com>
[Remove now useless conditionals. - Paolo]
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
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Currently we make sequence == 0 be the same as sequence == 1, but that's
not super useful if the intent is really to have a timeout that's just
a pure timeout.
If the user passes in sqe->off == 0, then don't apply any sequence logic
to the request, let it purely be driven by the timeout specified.
Reported-by: 李通洲 <carter.li@eoitek.com>
Reviewed-by: 李通洲 <carter.li@eoitek.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
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This fixes two different classes of bugs in the Intel graphics hardware:
MMIO register read hang:
"On Intels Gen8 and Gen9 Graphics hardware, a read of specific graphics
MMIO registers when the product is in certain low power states causes
a system hang.
There are two potential triggers for DoS:
a) H/W corruption of the RC6 save/restore vector
b) Hard hang within the MIPI hardware
This prevents the DoS in two areas of the hardware:
1) Detect corruption of RC6 address on exit from low-power state,
and if we find it corrupted, disable RC6 and RPM
2) Permanently lower the MIPI MMIO timeout"
Blitter command streamer unrestricted memory accesses:
"On Intels Gen9 Graphics hardware the Blitter Command Streamer (BCS)
allows writing to Memory Mapped Input Output (MMIO) that should be
blocked. With modifications of page tables, this can lead to privilege
escalation. This exposure is limited to the Guest Physical Address
space and does not allow for access outside of the graphics virtual
machine.
This series establishes a software parser into the Blitter command
stream to scan for, and prevent, reads or writes to MMIO's that should
not be accessible to non-privileged contexts.
Much of the command parser infrastructure has existed for some time,
and is used on Ivybridge/Haswell/Valleyview derived products to allow
the use of features normally blocked by hardware. In this legacy
context, the command parser is employed to allow normally unprivileged
submissions to be run with elevated privileges in order to grant
access to a limited set of extra capabilities. In this mode the parser
is optional; In the event that the parser finds any construct that it
cannot properly validate (e.g. nested command buffers), it simply
aborts the scan and submits the buffer in non-privileged mode.
For Gen9 Graphics, this series makes the parser mandatory for all
Blitter submissions. The incoming user buffer is first copied to a
kernel owned buffer, and parsed. If all checks are successful the
kernel owned buffer is mapped READ-ONLY and submitted on behalf of the
user. If any checks fail, or the parser is unable to complete the scan
(nested buffers), it is forcibly rejected. The successfully scanned
buffer is executed with NORMAL user privileges (key difference from
legacy usage).
Modern usermode does not use the Blitter on later hardware, having
switched over to using the 3D engine instead for performance reasons.
There are however some legacy usermode apps that rely on Blitter,
notably the SNA X-Server. There are no known usermode applications
that require nested command buffers on the Blitter, so the forcible
rejection of such buffers in this patch series is considered an
acceptable limitation"
* Intel graphics fixes in emailed bundle from Jon Bloomfield <jon.bloomfield@intel.com>:
drm/i915/cmdparser: Fix jump whitelist clearing
drm/i915/gen8+: Add RC6 CTX corruption WA
drm/i915: Lower RM timeout to avoid DSI hard hangs
drm/i915/cmdparser: Ignore Length operands during command matching
drm/i915/cmdparser: Add support for backward jumps
drm/i915/cmdparser: Use explicit goto for error paths
drm/i915: Add gen9 BCS cmdparsing
drm/i915: Allow parsing of unsized batches
drm/i915: Support ro ppgtt mapped cmdparser shadow buffers
drm/i915: Add support for mandatory cmdparsing
drm/i915: Remove Master tables from cmdparser
drm/i915: Disable Secure Batches for gen6+
drm/i915: Rename gen7 cmdparser tables
|
|
git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup
Pull cgroup fix from Tejun Heo:
"There's an inadvertent preemption point in ptrace_stop() which was
reliably triggering for a test scenario significantly slowing it down.
This contains Oleg's fix to remove the unwanted preemption point"
* 'for-5.4-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup:
cgroup: freezer: call cgroup_enter_frozen() with preemption disabled in ptrace_stop()
|
|
During rename exchange we might have successfully log the new name in the
source root's log tree, in which case we leave our log context (allocated
on stack) in the root's list of log contextes. However we might fail to
log the new name in the destination root, in which case we fallback to
a transaction commit later and never sync the log of the source root,
which causes the source root log context to remain in the list of log
contextes. This later causes invalid memory accesses because the context
was allocated on stack and after rename exchange finishes the stack gets
reused and overwritten for other purposes.
The kernel's linked list corruption detector (CONFIG_DEBUG_LIST=y) can
detect this and report something like the following:
[ 691.489929] ------------[ cut here ]------------
[ 691.489947] list_add corruption. prev->next should be next (ffff88819c944530), but was ffff8881c23f7be4. (prev=ffff8881c23f7a38).
[ 691.489967] WARNING: CPU: 2 PID: 28933 at lib/list_debug.c:28 __list_add_valid+0x95/0xe0
(...)
[ 691.489998] CPU: 2 PID: 28933 Comm: fsstress Not tainted 5.4.0-rc6-btrfs-next-62 #1
[ 691.490001] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.12.0-0-ga698c8995f-prebuilt.qemu.org 04/01/2014
[ 691.490003] RIP: 0010:__list_add_valid+0x95/0xe0
(...)
[ 691.490007] RSP: 0018:ffff8881f0b3faf8 EFLAGS: 00010282
[ 691.490010] RAX: 0000000000000000 RBX: ffff88819c944530 RCX: 0000000000000000
[ 691.490011] RDX: 0000000000000001 RSI: 0000000000000008 RDI: ffffffffa2c497e0
[ 691.490013] RBP: ffff8881f0b3fe68 R08: ffffed103eaa4115 R09: ffffed103eaa4114
[ 691.490015] R10: ffff88819c944000 R11: ffffed103eaa4115 R12: 7fffffffffffffff
[ 691.490016] R13: ffff8881b4035610 R14: ffff8881e7b84728 R15: 1ffff1103e167f7b
[ 691.490019] FS: 00007f4b25ea2e80(0000) GS:ffff8881f5500000(0000) knlGS:0000000000000000
[ 691.490021] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 691.490022] CR2: 00007fffbb2d4eec CR3: 00000001f2a4a004 CR4: 00000000003606e0
[ 691.490025] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[ 691.490027] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[ 691.490029] Call Trace:
[ 691.490058] btrfs_log_inode_parent+0x667/0x2730 [btrfs]
[ 691.490083] ? join_transaction+0x24a/0xce0 [btrfs]
[ 691.490107] ? btrfs_end_log_trans+0x80/0x80 [btrfs]
[ 691.490111] ? dget_parent+0xb8/0x460
[ 691.490116] ? lock_downgrade+0x6b0/0x6b0
[ 691.490121] ? rwlock_bug.part.0+0x90/0x90
[ 691.490127] ? do_raw_spin_unlock+0x142/0x220
[ 691.490151] btrfs_log_dentry_safe+0x65/0x90 [btrfs]
[ 691.490172] btrfs_sync_file+0x9f1/0xc00 [btrfs]
[ 691.490195] ? btrfs_file_write_iter+0x1800/0x1800 [btrfs]
[ 691.490198] ? rcu_read_lock_any_held.part.11+0x20/0x20
[ 691.490204] ? __do_sys_newstat+0x88/0xd0
[ 691.490207] ? cp_new_stat+0x5d0/0x5d0
[ 691.490218] ? do_fsync+0x38/0x60
[ 691.490220] do_fsync+0x38/0x60
[ 691.490224] __x64_sys_fdatasync+0x32/0x40
[ 691.490228] do_syscall_64+0x9f/0x540
[ 691.490233] entry_SYSCALL_64_after_hwframe+0x49/0xbe
[ 691.490235] RIP: 0033:0x7f4b253ad5f0
(...)
[ 691.490239] RSP: 002b:00007fffbb2d6078 EFLAGS: 00000246 ORIG_RAX: 000000000000004b
[ 691.490242] RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00007f4b253ad5f0
[ 691.490244] RDX: 00007fffbb2d5fe0 RSI: 00007fffbb2d5fe0 RDI: 0000000000000003
[ 691.490245] RBP: 000000000000000d R08: 0000000000000001 R09: 00007fffbb2d608c
[ 691.490247] R10: 00000000000002e8 R11: 0000000000000246 R12: 00000000000001f4
[ 691.490248] R13: 0000000051eb851f R14: 00007fffbb2d6120 R15: 00005635a498bda0
This started happening recently when running some test cases from fstests
like btrfs/004 for example, because support for rename exchange was added
last week to fsstress from fstests.
So fix this by deleting the log context for the source root from the list
if we have logged the new name in the source root.
Reported-by: Su Yue <Damenly_Su@gmx.com>
Fixes: d4682ba03ef618 ("Btrfs: sync log after logging new name")
CC: stable@vger.kernel.org # 4.19+
Tested-by: Su Yue <Damenly_Su@gmx.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
|
|
git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi
Pull SCSI fixes from James Bottomley:
"Three small changes: two in the core and one in the qla2xxx driver.
The sg_tablesize fix affects a thinko in the migration to blk-mq of
certain legacy drivers which could cause an oops and the sd core
change should only affect zoned block devices which were wrongly
suppressing error messages for reset all zones"
* tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi:
scsi: core: Handle drivers which set sg_tablesize to zero
scsi: qla2xxx: fix NPIV tear down process
scsi: sd_zbc: Fix sd_zbc_complete()
|
|
When a jump_whitelist bitmap is reused, it needs to be cleared.
Currently this is done with memset() and the size calculation assumes
bitmaps are made of 32-bit words, not longs. So on 64-bit
architectures, only the first half of the bitmap is cleared.
If some whitelist bits are carried over between successive batches
submitted on the same context, this will presumably allow embedding
the rogue instructions that we're trying to reject.
Use bitmap_zero() instead, which gets the calculation right.
Fixes: f8c08d8faee5 ("drm/i915/cmdparser: Add support for backward jumps")
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: Jon Bloomfield <jon.bloomfield@intel.com>
|
|
Reported by syzkaller:
=============================
WARNING: suspicious RCU usage
-----------------------------
./include/linux/kvm_host.h:536 suspicious rcu_dereference_check() usage!
other info that might help us debug this:
rcu_scheduler_active = 2, debug_locks = 1
no locks held by repro_11/12688.
stack backtrace:
Call Trace:
dump_stack+0x7d/0xc5
lockdep_rcu_suspicious+0x123/0x170
kvm_dev_ioctl+0x9a9/0x1260 [kvm]
do_vfs_ioctl+0x1a1/0xfb0
ksys_ioctl+0x6d/0x80
__x64_sys_ioctl+0x73/0xb0
do_syscall_64+0x108/0xaa0
entry_SYSCALL_64_after_hwframe+0x49/0xbe
Commit a97b0e773e4 (kvm: call kvm_arch_destroy_vm if vm creation fails)
sets users_count to 1 before kvm_arch_init_vm(), however, if kvm_arch_init_vm()
fails, we need to decrease this count. By moving it earlier, we can push
the decrease to out_err_no_arch_destroy_vm without introducing yet another
error label.
syzkaller source: https://syzkaller.appspot.com/x/repro.c?x=15209b84e00000
Reported-by: syzbot+75475908cd0910f141ee@syzkaller.appspotmail.com
Fixes: a97b0e773e49 ("kvm: call kvm_arch_destroy_vm if vm creation fails")
Cc: Jim Mattson <jmattson@google.com>
Analyzed-by: Wanpeng Li <wanpengli@tencent.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
|
|
Reported by syzkaller:
kasan: CONFIG_KASAN_INLINE enabled
kasan: GPF could be caused by NULL-ptr deref or user memory access
general protection fault: 0000 [#1] PREEMPT SMP KASAN
CPU: 0 PID: 14727 Comm: syz-executor.3 Not tainted 5.4.0-rc4+ #0
RIP: 0010:kvm_coalesced_mmio_init+0x5d/0x110 arch/x86/kvm/../../../virt/kvm/coalesced_mmio.c:121
Call Trace:
kvm_dev_ioctl_create_vm arch/x86/kvm/../../../virt/kvm/kvm_main.c:3446 [inline]
kvm_dev_ioctl+0x781/0x1490 arch/x86/kvm/../../../virt/kvm/kvm_main.c:3494
vfs_ioctl fs/ioctl.c:46 [inline]
file_ioctl fs/ioctl.c:509 [inline]
do_vfs_ioctl+0x196/0x1150 fs/ioctl.c:696
ksys_ioctl+0x62/0x90 fs/ioctl.c:713
__do_sys_ioctl fs/ioctl.c:720 [inline]
__se_sys_ioctl fs/ioctl.c:718 [inline]
__x64_sys_ioctl+0x6e/0xb0 fs/ioctl.c:718
do_syscall_64+0xca/0x5d0 arch/x86/entry/common.c:290
entry_SYSCALL_64_after_hwframe+0x49/0xbe
Commit 9121923c457d ("kvm: Allocate memslots and buses before calling kvm_arch_init_vm")
moves memslots and buses allocations around, however, if kvm->srcu/irq_srcu fails
initialization, NULL will be returned instead of error code, NULL will not be intercepted
in kvm_dev_ioctl_create_vm() and be dereferenced by kvm_coalesced_mmio_init(), this patch
fixes it.
Moving the initialization is required anyway to avoid an incorrect synchronize_srcu that
was also reported by syzkaller:
wait_for_completion+0x29c/0x440 kernel/sched/completion.c:136
__synchronize_srcu+0x197/0x250 kernel/rcu/srcutree.c:921
synchronize_srcu_expedited kernel/rcu/srcutree.c:946 [inline]
synchronize_srcu+0x239/0x3e8 kernel/rcu/srcutree.c:997
kvm_page_track_unregister_notifier+0xe7/0x130 arch/x86/kvm/page_track.c:212
kvm_mmu_uninit_vm+0x1e/0x30 arch/x86/kvm/mmu.c:5828
kvm_arch_destroy_vm+0x4a2/0x5f0 arch/x86/kvm/x86.c:9579
kvm_create_vm arch/x86/kvm/../../../virt/kvm/kvm_main.c:702 [inline]
so do it.
Reported-by: syzbot+89a8060879fa0bd2db4f@syzkaller.appspotmail.com
Reported-by: syzbot+e27e7027eb2b80e44225@syzkaller.appspotmail.com
Fixes: 9121923c457d ("kvm: Allocate memslots and buses before calling kvm_arch_init_vm")
Cc: Jim Mattson <jmattson@google.com>
Cc: Wanpeng Li <wanpengli@tencent.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
|
|
Apply same logic to pin setup as on previous platforms. Fixes
errors in HDMI/DP playback.
Tested with both snd-hda-intel and SOF drivers.
Fixes: 9a11ba7388f1 ("ALSA: hda: hdmi - add Tigerlake support")
Signed-off-by: Kai Vehmanen <kai.vehmanen@linux.intel.com>
Link: https://lore.kernel.org/r/20191111133838.21213-1-kai.vehmanen@linux.intel.com
Signed-off-by: Takashi Iwai <tiwai@suse.de>
|
|
Add HD Audio Device PCI ID for the Intel Cometlake-S platform
Signed-off-by: Chiou, Cooper <cooper.chiou@intel.com>
Link: https://lore.kernel.org/r/20191108071349.12840-1-cooper.chiou@intel.com
Signed-off-by: Takashi Iwai <tiwai@suse.de>
|
|
|
|
git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc
Pull ARM SoC fixes from Olof Johansson:
"A set of fixes that have trickled in over the last couple of weeks:
- MAINTAINER update for Cavium/Marvell ThunderX2
- stm32 tweaks to pinmux for Joystick/Camera, and RAM allocation for
CAN interfaces
- i.MX fixes for voltage regulator GPIO mappings, fixes voltage
scaling issues
- More i.MX fixes for various issues on i.MX eval boards: interrupt
storm due to u-boot leaving pins in new states, fixing power button
config, a couple of compatible-string corrections.
- Powerdown and Suspend/Resume fixes for Allwinner A83-based tablets
- A few documentation tweaks and a fix of a memory leak in the reset
subsystem"
* tag 'armsoc-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc:
MAINTAINERS: update Cavium ThunderX2 maintainers
ARM: dts: stm32: change joystick pinctrl definition on stm32mp157c-ev1
ARM: dts: stm32: remove OV5640 pinctrl definition on stm32mp157c-ev1
ARM: dts: stm32: Fix CAN RAM mapping on stm32mp157c
ARM: dts: stm32: relax qspi pins slew-rate for stm32mp157
arm64: dts: zii-ultra: fix ARM regulator GPIO handle
ARM: sunxi: Fix CPU powerdown on A83T
ARM: dts: sun8i-a83t-tbs-a711: Fix WiFi resume from suspend
arm64: dts: imx8mn: fix compatible string for sdma
arm64: dts: imx8mm: fix compatible string for sdma
reset: fix reset_control_ops kerneldoc comment
ARM: dts: imx6-logicpd: Re-enable SNVS power key
soc: imx: gpc: fix initialiser format
ARM: dts: imx6qdl-sabreauto: Fix storm of accelerometer interrupts
arm64: dts: ls1028a: fix a compatible issue
reset: fix reset_control_get_exclusive kerneldoc comment
reset: fix reset_control_lookup kerneldoc comment
reset: fix of_reset_control_get_count kerneldoc comment
reset: fix of_reset_simple_xlate kerneldoc comment
reset: Fix memory leak in reset_control_array_put()
|
|
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging
Pull IIO fixes and staging driver from Greg KH:
"Here is a mix of a number of IIO driver fixes for 5.4-rc7, and a whole
new staging driver.
The IIO fixes resolve some reported issues, all are tiny.
The staging driver addition is the vboxsf filesystem, which is the
VirtualBox guest shared folder code. Hans has been trying to get
filesystem reviewers to review the code for many months now, and
Christoph finally said to just merge it in staging now as it is
stand-alone and the filesystem people can review it easier over time
that way.
I know it's late for this big of an addition, but it is stand-alone.
The code has been in linux-next for a while, long enough to pick up a
few tiny fixes for it already so people are looking at it.
All of these have been in linux-next with no reported issues"
* tag 'staging-5.4-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging:
staging: Fix error return code in vboxsf_fill_super()
staging: vboxsf: fix dereference of pointer dentry before it is null checked
staging: vboxsf: Remove unused including <linux/version.h>
staging: Add VirtualBox guest shared folder (vboxsf) support
iio: adc: stm32-adc: fix stopping dma
iio: imu: inv_mpu6050: fix no data on MPU6050
iio: srf04: fix wrong limitation in distance measuring
iio: imu: adis16480: make sure provided frequency is positive
|
|
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc
Pull char/misc driver fixes from Greg KH:
"Here are a number of late-arrival driver fixes for issues reported for
some char/misc drivers for 5.4-rc7
These all come from the different subsystem/driver maintainers as
things that they had reports for and wanted to see fixed.
All of these have been in linux-next with no reported issues"
* tag 'char-misc-5.4-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc:
intel_th: pci: Add Jasper Lake PCH support
intel_th: pci: Add Comet Lake PCH support
intel_th: msu: Fix possible memory leak in mode_store()
intel_th: msu: Fix overflow in shift of an unsigned int
intel_th: msu: Fix missing allocation failure check on a kstrndup
intel_th: msu: Fix an uninitialized mutex
intel_th: gth: Fix the window switching sequence
soundwire: slave: fix scanf format
soundwire: intel: fix intel_register_dai PDI offsets and numbers
interconnect: Add locking in icc_set_tag()
interconnect: qcom: Fix icc_onecell_data allocation
soundwire: depend on ACPI || OF
soundwire: depend on ACPI
thunderbolt: Drop unnecessary read when writing LC command in Ice Lake
thunderbolt: Fix lockdep circular locking depedency warning
thunderbolt: Read DP IN adapter first two dwords in one go
|
|
Pull configfs regression fix from Christoph Hellwig:
"Fix a regression from this merge window in the configfs symlink
handling (Honggang Li)"
* tag 'configfs-for-5.4-2' of git://git.infradead.org/users/hch/configfs:
configfs: calculate the depth of parent item
|
|
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 fixes from Thomas Gleixner:
"A small set of fixes for x86:
- Make the tsc=reliable/nowatchdog command line parameter work again.
It was broken with the introduction of the early TSC clocksource.
- Prevent the evaluation of exception stacks before they are set up.
This causes a crash in dumpstack because the stack walk termination
gets screwed up.
- Prevent a NULL pointer dereference in the rescource control file
system.
- Avoid bogus warnings about APIC id mismatch related to the LDR
which can happen when the LDR is not in use and therefore not
initialized. Only evaluate that when the APIC is in logical
destination mode"
* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/tsc: Respect tsc command line paraemeter for clocksource_tsc_early
x86/dumpstack/64: Don't evaluate exception stacks before setup
x86/apic/32: Avoid bogus LDR warnings
x86/resctrl: Prevent NULL pointer dereference when reading mondata
|
|
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull timer fixes from Thomas Gleixner:
"A small set of fixes for timekeepoing and clocksource drivers:
- VDSO data was updated conditional on the availability of a VDSO
capable clocksource. This causes the VDSO functions which do not
depend on a VDSO capable clocksource to operate on stale data.
Always update unconditionally.
- Prevent a double free in the mediatek driver
- Use the proper helper in the sh_mtu2 driver so it won't attempt to
initialize non-existing interrupts"
* 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
timekeeping/vsyscall: Update VDSO data unconditionally
clocksource/drivers/sh_mtu2: Do not loop using platform_get_irq_by_name()
clocksource/drivers/mediatek: Fix error handling
|
|
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull scheduler fixes from Thomas Gleixner:
"Two fixes for scheduler regressions:
- Plug a subtle race condition which was introduced with the rework
of the next task selection functionality. The change of task
properties became unprotected which can be observed inconsistently
causing state corruption.
- A trivial compile fix for CONFIG_CGROUPS=n"
* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
sched: Fix pick_next_task() vs 'change' pattern race
sched/core: Fix compilation error when cgroup not selected
|
|
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull perf tooling fixes from Thomas Gleixner:
- Fix the time sorting algorithm which was broken due to truncation of
big numbers
- Fix the python script generator fail caused by a broken tracepoint
array iterator
* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
perf tools: Fix time sorting
perf tools: Remove unused trace_find_next_event()
perf scripting engines: Iterate on tep event arrays directly
|
|
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull irq fixlet from Thomas Gleixner:
"A trivial fix for a kernel doc regression where an argument change was
not reflected in the documentation"
* 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
irq/irqdomain: Update __irq_domain_alloc_fwnode() function documentation
|
|
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull stacktrace fix from Thomas Gleixner:
"A small fix for a stacktrace regression.
Saving a stacktrace for a foreign task skipped an extra entry which
makes e.g. the output of /proc/$PID/stack incomplete"
* 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
stacktrace: Don't skip first entry on noncurrent tasks
|
|
Pull cifs fix from Steve French:
"Small fix for an smb3 reconnect bug (also marked for stable)"
* tag '5.4-rc7-smb3-fix' of git://git.samba.org/sfrench/cifs-2.6:
SMB3: Fix persistent handles reconnect
|
|
config option GENERIC_IO was removed but still selected by lib/kconfig
This patch finish the cleaning.
Fixes: 9de8da47742b ("kconfig: kill off GENERIC_IO option")
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Corentin Labbe <clabbe@baylibre.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
We need to get the underlying dentry of parent; sure, absent the races
it is the parent of underlying dentry, but there's nothing to prevent
losing a timeslice to preemtion in the middle of evaluation of
lower_dentry->d_parent->d_inode, having another process move lower_dentry
around and have its (ex)parent not pinned anymore and freed on memory
pressure. Then we regain CPU and try to fetch ->d_inode from memory
that is freed by that point.
dentry->d_parent *is* stable here - it's an argument of ->lookup() and
we are guaranteed that it won't be moved anywhere until we feed it
to d_add/d_splice_alias. So we safely go that way to get to its
underlying dentry.
Cc: stable@vger.kernel.org # since 2009 or so
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
|
|
lower_dentry can't go from positive to negative (we have it pinned),
but it *can* go from negative to positive. So fetching ->d_inode
into a local variable, doing a blocking allocation, checking that
now ->d_inode is non-NULL and feeding the value we'd fetched
earlier to a function that won't accept NULL is not a good idea.
Cc: stable@vger.kernel.org
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
|
|
A problem similar to the one caught in commit 74dd7c97ea2a ("ecryptfs_rename():
verify that lower dentries are still OK after lock_rename()") exists for
unlink/rmdir as well.
Instead of playing with dget_parent() of underlying dentry of victim
and hoping it's the same as underlying dentry of our directory,
do the following:
* find the underlying dentry of victim
* find the underlying directory of victim's parent (stable
since the victim is ecryptfs dentry and inode of its parent is
held exclusive by the caller).
* lock the inode of dentry underlying the victim's parent
* check that underlying dentry of victim is still hashed and
has the right parent - it can be moved, but it can't be moved to/from
the directory we are holding exclusive. So while ->d_parent itself
might not be stable, the result of comparison is.
If the check passes, everything is fine - underlying directory is locked,
underlying victim is still a child of that directory and we can go ahead
and feed them to vfs_unlink(). As in the current mainline we need to
pin the underlying dentry of victim, so that it wouldn't go negative under
us, but that's the only temporary reference that needs to be grabbed there.
Underlying dentry of parent won't go away (it's pinned by the parent,
which is held by caller), so there's no need to grab it.
The same problem (with the same solution) exists for rmdir. Moreover,
rename gets simpler and more robust with the same "don't bother with
dget_parent()" approach.
Fixes: 74dd7c97ea2 "ecryptfs_rename(): verify that lower dentries are still OK after lock_rename()"
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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if the child has been negative and just went positive
under us, we want coherent d_is_positive() and ->d_inode.
Don't unlock the parent until we'd done that work...
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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