976573 Commits

Author SHA1 Message Date
Shreyansh Chouhan
ecd8614809 reiserfs: check directory items on read from disk
[ Upstream commit 13d257503c0930010ef9eed78b689cec417ab741 ]

While verifying the leaf item that we read from the disk, reiserfs
doesn't check the directory items, this could cause a crash when we
read a directory item from the disk that has an invalid deh_location.

This patch adds a check to the directory items read from the disk that
does a bounds check on deh_location for the directory entries. Any
directory entry header with a directory entry offset greater than the
item length is considered invalid.

Link: https://lore.kernel.org/r/20210709152929.766363-1-chouhan.shreyansh630@gmail.com
Reported-by: syzbot+c31a48e6702ccb3d64c9@syzkaller.appspotmail.com
Signed-off-by: Shreyansh Chouhan <chouhan.shreyansh630@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-08-12 13:22:19 +02:00
Yu Kuai
dbe4f82fed reiserfs: add check for root_inode in reiserfs_fill_super
[ Upstream commit 2acf15b94d5b8ea8392c4b6753a6ffac3135cd78 ]

Our syzcaller report a NULL pointer dereference:

BUG: kernel NULL pointer dereference, address: 0000000000000000
PGD 116e95067 P4D 116e95067 PUD 1080b5067 PMD 0
Oops: 0010 [#1] SMP KASAN
CPU: 7 PID: 592 Comm: a.out Not tainted 5.13.0-next-20210629-dirty #67
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS ?-20190727_073836-buildvm-p4
RIP: 0010:0x0
Code: Unable to access opcode bytes at RIP 0xffffffffffffffd6.
RSP: 0018:ffff888114e779b8 EFLAGS: 00010246
RAX: 0000000000000000 RBX: 1ffff110229cef39 RCX: ffffffffaa67e1aa
RDX: 0000000000000000 RSI: ffff88810a58ee00 RDI: ffff8881233180b0
RBP: ffffffffac38e9c0 R08: ffffffffaa67e17e R09: 0000000000000001
R10: ffffffffb91c5557 R11: fffffbfff7238aaa R12: ffff88810a58ee00
R13: ffff888114e77aa0 R14: 0000000000000000 R15: ffff8881233180b0
FS:  00007f946163c480(0000) GS:ffff88839f1c0000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffffffffffffffd6 CR3: 00000001099c1000 CR4: 00000000000006e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 __lookup_slow+0x116/0x2d0
 ? page_put_link+0x120/0x120
 ? __d_lookup+0xfc/0x320
 ? d_lookup+0x49/0x90
 lookup_one_len+0x13c/0x170
 ? __lookup_slow+0x2d0/0x2d0
 ? reiserfs_schedule_old_flush+0x31/0x130
 reiserfs_lookup_privroot+0x64/0x150
 reiserfs_fill_super+0x158c/0x1b90
 ? finish_unfinished+0xb10/0xb10
 ? bprintf+0xe0/0xe0
 ? __mutex_lock_slowpath+0x30/0x30
 ? __kasan_check_write+0x20/0x30
 ? up_write+0x51/0xb0
 ? set_blocksize+0x9f/0x1f0
 mount_bdev+0x27c/0x2d0
 ? finish_unfinished+0xb10/0xb10
 ? reiserfs_kill_sb+0x120/0x120
 get_super_block+0x19/0x30
 legacy_get_tree+0x76/0xf0
 vfs_get_tree+0x49/0x160
 ? capable+0x1d/0x30
 path_mount+0xacc/0x1380
 ? putname+0x97/0xd0
 ? finish_automount+0x450/0x450
 ? kmem_cache_free+0xf8/0x5a0
 ? putname+0x97/0xd0
 do_mount+0xe2/0x110
 ? path_mount+0x1380/0x1380
 ? copy_mount_options+0x69/0x140
 __x64_sys_mount+0xf0/0x190
 do_syscall_64+0x35/0x80
 entry_SYSCALL_64_after_hwframe+0x44/0xae

This is because 'root_inode' is initialized with wrong mode, and
it's i_op is set to 'reiserfs_special_inode_operations'. Thus add
check for 'root_inode' to fix the problem.

Link: https://lore.kernel.org/r/20210702040743.1918552-1-yukuai3@huawei.com
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-08-12 13:22:19 +02:00
Christoph Hellwig
0f05e0ffa2 libata: fix ata_pio_sector for CONFIG_HIGHMEM
[ Upstream commit ecef6a9effe49e8e2635c839020b9833b71e934c ]

Data transfers are not required to be block aligned in memory, so they
span two pages.  Fix this by splitting the call to >sff_data_xfer into
two for that case.

This has been broken since the initial libata import before the damn
of git, but was uncovered by the legacy ide driver removal.

Reported-by: kernel test robot <oliver.sang@intel.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20210709130237.3730959-1-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-08-12 13:22:19 +02:00
Jonathan Gray
11891adab2 drm/i915: avoid uninitialised var in eb_parse()
The backport of c9d9fdbc108af8915d3f497bbdf3898bf8f321b8 to 5.10 in
6976f3cf34a1a8b791c048bbaa411ebfe48666b1 removed more than it should
have leading to 'batch' being used uninitialised.  The 5.13 backport and
the mainline commit did not remove the portion this patch adds back.

Signed-off-by: Jonathan Gray <jsg@jsg.id.au>
Fixes: 6976f3cf34a1 ("drm/i915: Revert "drm/i915/gem: Asynchronous cmdparser"")
Cc: <stable@vger.kernel.org> # 5.10
Cc: Jason Ekstrand <jason@jlekstrand.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-08-12 13:22:19 +02:00
Peter Zijlstra
a3e6bd0c71 sched/rt: Fix double enqueue caused by rt_effective_prio
commit f558c2b834ec27e75d37b1c860c139e7b7c3a8e4 upstream.

Double enqueues in rt runqueues (list) have been reported while running
a simple test that spawns a number of threads doing a short sleep/run
pattern while being concurrently setscheduled between rt and fair class.

  WARNING: CPU: 3 PID: 2825 at kernel/sched/rt.c:1294 enqueue_task_rt+0x355/0x360
  CPU: 3 PID: 2825 Comm: setsched__13
  RIP: 0010:enqueue_task_rt+0x355/0x360
  Call Trace:
   __sched_setscheduler+0x581/0x9d0
   _sched_setscheduler+0x63/0xa0
   do_sched_setscheduler+0xa0/0x150
   __x64_sys_sched_setscheduler+0x1a/0x30
   do_syscall_64+0x33/0x40
   entry_SYSCALL_64_after_hwframe+0x44/0xae

  list_add double add: new=ffff9867cb629b40, prev=ffff9867cb629b40,
		       next=ffff98679fc67ca0.
  kernel BUG at lib/list_debug.c:31!
  invalid opcode: 0000 [#1] PREEMPT_RT SMP PTI
  CPU: 3 PID: 2825 Comm: setsched__13
  RIP: 0010:__list_add_valid+0x41/0x50
  Call Trace:
   enqueue_task_rt+0x291/0x360
   __sched_setscheduler+0x581/0x9d0
   _sched_setscheduler+0x63/0xa0
   do_sched_setscheduler+0xa0/0x150
   __x64_sys_sched_setscheduler+0x1a/0x30
   do_syscall_64+0x33/0x40
   entry_SYSCALL_64_after_hwframe+0x44/0xae

__sched_setscheduler() uses rt_effective_prio() to handle proper queuing
of priority boosted tasks that are setscheduled while being boosted.
rt_effective_prio() is however called twice per each
__sched_setscheduler() call: first directly by __sched_setscheduler()
before dequeuing the task and then by __setscheduler() to actually do
the priority change. If the priority of the pi_top_task is concurrently
being changed however, it might happen that the two calls return
different results. If, for example, the first call returned the same rt
priority the task was running at and the second one a fair priority, the
task won't be removed by the rt list (on_list still set) and then
enqueued in the fair runqueue. When eventually setscheduled back to rt
it will be seen as enqueued already and the WARNING/BUG be issued.

Fix this by calling rt_effective_prio() only once and then reusing the
return value. While at it refactor code as well for clarity. Concurrent
priority inheritance handling is still safe and will eventually converge
to a new state by following the inheritance chain(s).

Fixes: 0782e63bc6fe ("sched: Handle priority boosted tasks proper in setscheduler()")
[squashed Peterz changes; added changelog]
Reported-by: Mark Simmons <msimmons@redhat.com>
Signed-off-by: Juri Lelli <juri.lelli@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20210803104501.38333-1-juri.lelli@redhat.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-08-12 13:22:19 +02:00
Like Xu
c797b8872b perf/x86/amd: Don't touch the AMD64_EVENTSEL_HOSTONLY bit inside the guest
commit df51fe7ea1c1c2c3bfdb81279712fdd2e4ea6c27 upstream.

If we use "perf record" in an AMD Milan guest, dmesg reports a #GP
warning from an unchecked MSR access error on MSR_F15H_PERF_CTLx:

  [] unchecked MSR access error: WRMSR to 0xc0010200 (tried to write 0x0000020000110076) at rIP: 0xffffffff8106ddb4 (native_write_msr+0x4/0x20)
  [] Call Trace:
  []  amd_pmu_disable_event+0x22/0x90
  []  x86_pmu_stop+0x4c/0xa0
  []  x86_pmu_del+0x3a/0x140

The AMD64_EVENTSEL_HOSTONLY bit is defined and used on the host,
while the guest perf driver should avoid such use.

Fixes: 1018faa6cf23 ("perf/x86/kvm: Fix Host-Only/Guest-Only counting with SVM disabled")
Signed-off-by: Like Xu <likexu@tencent.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Liam Merwick <liam.merwick@oracle.com>
Tested-by: Kim Phillips <kim.phillips@amd.com>
Tested-by: Liam Merwick <liam.merwick@oracle.com>
Link: https://lkml.kernel.org/r/20210802070850.35295-1-likexu@tencent.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-08-12 13:22:19 +02:00
Arnd Bergmann
2d94cffc94 soc: ixp4xx/qmgr: fix invalid __iomem access
commit a8eee86317f11e97990d755d4615c1c0db203d08 upstream.

Sparse reports a compile time warning when dereferencing an
__iomem pointer:

drivers/soc/ixp4xx/ixp4xx-qmgr.c:149:37: warning: dereference of noderef expression
drivers/soc/ixp4xx/ixp4xx-qmgr.c:153:40: warning: dereference of noderef expression
drivers/soc/ixp4xx/ixp4xx-qmgr.c:154:40: warning: dereference of noderef expression
drivers/soc/ixp4xx/ixp4xx-qmgr.c:174:38: warning: dereference of noderef expression
drivers/soc/ixp4xx/ixp4xx-qmgr.c:174:44: warning: dereference of noderef expression

Use __raw_readl() here for consistency with the rest of the file.
This should really get converted to some proper accessor, as the
__raw functions are not meant to be used in drivers, but the driver
has used these since the start, so for the moment, let's only fix
the warning.

Reported-by: kernel test robot <lkp@intel.com>
Fixes: d4c9e9fc9751 ("IXP42x: Add QMgr support for IXP425 rev. A0 processors.")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-08-12 13:22:18 +02:00
Matt Roper
7397034905 drm/i915: Correct SFC_DONE register offset
commit 9c9c6d0ab08acfe41c9f7efa72c4ad3f133a266b upstream.

The register offset for SFC_DONE was missing a '0' at the end, causing
us to read from a non-existent register address.  We only use this
register in error state dumps so the mistake hasn't caused any real
problems, but fixing it will hopefully make the error state dumps a bit
more useful for debugging.

Fixes: e50dbdbfd9fb ("drm/i915/tgl: Add SFC instdone to error state")
Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Signed-off-by: Matt Roper <matthew.d.roper@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210728233411.2365788-1-matthew.d.roper@intel.com
Reviewed-by: Mika Kuoppala <mika.kuoppala@linux.intel.com>
(cherry picked from commit 82929a2140eb99f1f1d21855f3f580e70d7abdd8)
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-08-12 13:22:18 +02:00
Mike Tipton
16aecf1e36 interconnect: qcom: icc-rpmh: Ensure floor BW is enforced for all nodes
commit ce5a595744126be4f1327e29e3c5ae9aac6b38d5 upstream.

We currently only enforce BW floors for a subset of nodes in a path.
All BCMs that need updating are queued in the pre_aggregate/aggregate
phase. The first set() commits all queued BCMs and subsequent set()
calls short-circuit without committing anything. Since the floor BW
isn't set in sum_avg/max_peak until set(), then some BCMs are committed
before their associated nodes reflect the floor.

Set the floor as each node is being aggregated. This ensures that all
all relevant floors are set before the BCMs are committed.

Fixes: 266cd33b5913 ("interconnect: qcom: Ensure that the floor bandwidth value is enforced")
Signed-off-by: Mike Tipton <mdtipton@codeaurora.org>
Link: https://lore.kernel.org/r/20210721175432.2119-4-mdtipton@codeaurora.org
[georgi: Removed unused variable]
Signed-off-by: Georgi Djakov <djakov@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-08-12 13:22:18 +02:00
Mike Tipton
22b4917c85 interconnect: Always call pre_aggregate before aggregate
commit 73606ba9242f8e32023699b500b7922b4cf2993c upstream.

The pre_aggregate callback isn't called in all cases before calling
aggregate. Add the missing calls so providers can rely on consistent
framework behavior.

Fixes: d3703b3e255f ("interconnect: Aggregate before setting initial bandwidth")
Signed-off-by: Mike Tipton <mdtipton@codeaurora.org>
Link: https://lore.kernel.org/r/20210721175432.2119-3-mdtipton@codeaurora.org
Signed-off-by: Georgi Djakov <djakov@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-08-12 13:22:18 +02:00
Mike Tipton
ccfe4f62ff interconnect: Zero initial BW after sync-state
commit 456a9dace42ecfcec7ce6e17c18d1985d628dcd0 upstream.

The initial BW values may be used by providers to enforce floors. Zero
these values after sync-state so that providers know when to stop
enforcing them.

Fixes: b1d681d8d324 ("interconnect: Add sync state support")
Signed-off-by: Mike Tipton <mdtipton@codeaurora.org>
Link: https://lore.kernel.org/r/20210721175432.2119-2-mdtipton@codeaurora.org
Signed-off-by: Georgi Djakov <djakov@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-08-12 13:22:18 +02:00
Dongliang Mu
05565b4693 spi: meson-spicc: fix memory leak in meson_spicc_remove
commit 8311ee2164c5cd1b63a601ea366f540eae89f10e upstream.

In meson_spicc_probe, the error handling code needs to clean up master
by calling spi_master_put, but the remove function does not have this
function call. This will lead to memory leak of spicc->master.

Reported-by: Dongliang Mu <mudongliangabcd@gmail.com>
Fixes: 454fa271bc4e("spi: Add Meson SPICC driver")
Signed-off-by: Dongliang Mu <mudongliangabcd@gmail.com>
Link: https://lore.kernel.org/r/20210720100116.1438974-1-mudongliangabcd@gmail.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-08-12 13:22:18 +02:00
Colin Ian King
1a084e7821 interconnect: Fix undersized devress_alloc allocation
commit 85b1ebfea2b0d8797266bcc6f04b6cc87e38290a upstream.

The expression sizeof(**ptr) for the void **ptr is just 1 rather than
the size of a pointer. Fix this by using sizeof(*ptr).

Addresses-Coverity: ("Wrong sizeof argument")
Fixes: e145d9a184f2 ("interconnect: Add devm_of_icc_get() as exported API for users")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Link: https://lore.kernel.org/r/20210730075408.19945-1-colin.king@canonical.com
Signed-off-by: Georgi Djakov <djakov@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-08-12 13:22:18 +02:00
Arnd Bergmann
dcc23e5851 soc: ixp4xx: fix printing resources
commit 8861452b2097bb0b5d0081a1c137fb3870b0a31f upstream.

When compile-testing with 64-bit resource_size_t, gcc reports an invalid
printk format string:

In file included from include/linux/dma-mapping.h:7,
                 from drivers/soc/ixp4xx/ixp4xx-npe.c:15:
drivers/soc/ixp4xx/ixp4xx-npe.c: In function 'ixp4xx_npe_probe':
drivers/soc/ixp4xx/ixp4xx-npe.c:694:18: error: format '%x' expects argument of type 'unsigned int', but argument 4 has type 'resource_size_t' {aka 'long long unsigned int'} [-Werror=format=]
    dev_info(dev, "NPE%d at 0x%08x-0x%08x not available\n",

Use the special %pR format string to print the resources.

Fixes: 0b458d7b10f8 ("soc: ixp4xx: npe: Pass addresses as resources")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-08-12 13:22:17 +02:00
Will Deacon
37cbd27ef4 arm64: vdso: Avoid ISB after reading from cntvct_el0
commit 77ec462536a13d4b428a1eead725c4818a49f0b1 upstream.

We can avoid the expensive ISB instruction after reading the counter in
the vDSO gettime functions by creating a fake address hazard against a
dummy stack read, just like we do inside the kernel.

Signed-off-by: Will Deacon <will@kernel.org>
Reviewed-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
Link: https://lore.kernel.org/r/20210318170738.7756-5-will@kernel.org
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Chanho Park <chanho61.park@samsung.com>
2021-08-12 13:22:17 +02:00
Sean Christopherson
7a2b5bb00f KVM: x86/mmu: Fix per-cpu counter corruption on 32-bit builds
commit d5aaad6f83420efb8357ac8e11c868708b22d0a9 upstream.

Take a signed 'long' instead of an 'unsigned long' for the number of
pages to add/subtract to the total number of pages used by the MMU.  This
fixes a zero-extension bug on 32-bit kernels that effectively corrupts
the per-cpu counter used by the shrinker.

Per-cpu counters take a signed 64-bit value on both 32-bit and 64-bit
kernels, whereas kvm_mod_used_mmu_pages() takes an unsigned long and thus
an unsigned 32-bit value on 32-bit kernels.  As a result, the value used
to adjust the per-cpu counter is zero-extended (unsigned -> signed), not
sign-extended (signed -> signed), and so KVM's intended -1 gets morphed to
4294967295 and effectively corrupts the counter.

This was found by a staggering amount of sheer dumb luck when running
kvm-unit-tests on a 32-bit KVM build.  The shrinker just happened to kick
in while running tests and do_shrink_slab() logged an error about trying
to free a negative number of objects.  The truly lucky part is that the
kernel just happened to be a slightly stale build, as the shrinker no
longer yells about negative objects as of commit 18bb473e5031 ("mm:
vmscan: shrink deferred objects proportional to priority").

 vmscan: shrink_slab: mmu_shrink_scan+0x0/0x210 [kvm] negative objects to delete nr=-858993460

Fixes: bc8a3d8925a8 ("kvm: mmu: Fix overflow on kvm mmu page limit calculation")
Cc: stable@vger.kernel.org
Cc: Ben Gardon <bgardon@google.com>
Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20210804214609.1096003-1-seanjc@google.com>
Reviewed-by: Jim Mattson <jmattson@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-08-12 13:22:17 +02:00
Paolo Bonzini
32f55c25ee KVM: Do not leak memory for duplicate debugfs directories
commit 85cd39af14f498f791d8aab3fbd64cd175787f1a upstream.

KVM creates a debugfs directory for each VM in order to store statistics
about the virtual machine.  The directory name is built from the process
pid and a VM fd.  While generally unique, it is possible to keep a
file descriptor alive in a way that causes duplicate directories, which
manifests as these messages:

  [  471.846235] debugfs: Directory '20245-4' with parent 'kvm' already present!

Even though this should not happen in practice, it is more or less
expected in the case of KVM for testcases that call KVM_CREATE_VM and
close the resulting file descriptor repeatedly and in parallel.

When this happens, debugfs_create_dir() returns an error but
kvm_create_vm_debugfs() goes on to allocate stat data structs which are
later leaked.  The slow memory leak was spotted by syzkaller, where it
caused OOM reports.

Since the issue only affects debugfs, do a lookup before calling
debugfs_create_dir, so that the message is downgraded and rate-limited.
While at it, ensure kvm->debugfs_dentry is NULL rather than an error
if it is not created.  This fixes kvm_destroy_vm_debugfs, which was not
checking IS_ERR_OR_NULL correctly.

Cc: stable@vger.kernel.org
Fixes: 536a6f88c49d ("KVM: Create debugfs dir and stat files for each VM")
Reported-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Suggested-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-08-12 13:22:17 +02:00
Paolo Bonzini
309a31127b KVM: x86: accept userspace interrupt only if no event is injected
commit fa7a549d321a4189677b0cea86e58d9db7977f7b upstream.

Once an exception has been injected, any side effects related to
the exception (such as setting CR2 or DR6) have been taked place.
Therefore, once KVM sets the VM-entry interruption information
field or the AMD EVENTINJ field, the next VM-entry must deliver that
exception.

Pending interrupts are processed after injected exceptions, so
in theory it would not be a problem to use KVM_INTERRUPT when
an injected exception is present.  However, DOSEMU is using
run->ready_for_interrupt_injection to detect interrupt windows
and then using KVM_SET_SREGS/KVM_SET_REGS to inject the
interrupt manually.  For this to work, the interrupt window
must be delayed after the completion of the previous event
injection.

Cc: stable@vger.kernel.org
Reported-by: Stas Sergeev <stsp2@yandex.ru>
Tested-by: Stas Sergeev <stsp2@yandex.ru>
Fixes: 71cc849b7093 ("KVM: x86: Fix split-irqchip vs interrupt injection window request")
Reviewed-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-08-12 13:22:17 +02:00
Wei Shuyu
a786282b55 md/raid10: properly indicate failure when ending a failed write request
commit 5ba03936c05584b6f6f79be5ebe7e5036c1dd252 upstream.

Similar to [1], this patch fixes the same bug in raid10. Also cleanup the
comments.

[1] commit 2417b9869b81 ("md/raid1: properly indicate failure when ending
                         a failed write request")
Cc: stable@vger.kernel.org
Fixes: 7cee6d4e6035 ("md/raid10: end bio when the device faulty")
Signed-off-by: Wei Shuyu <wsy@dogben.com>
Acked-by: Guoqing Jiang <jiangguoqing@kylinos.cn>
Signed-off-by: Song Liu <song@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-08-12 13:22:17 +02:00
Tero Kristo
3d7d2d2b06 ARM: omap2+: hwmod: fix potential NULL pointer access
commit b070f9ca78680486927b799cf6126b128a7c2c1b upstream.

omap_hwmod_get_pwrdm() may access a NULL clk_hw pointer in some failure
cases. Add a check for the case and bail out gracely if this happens.

Reported-by: Dan Murphy <dmurphy@ti.com>
Signed-off-by: Tero Kristo <t-kristo@ti.com>
Cc: stable@vger.kernel.org # v5.10+
Signed-off-by: Kevin Hilman <khilman@baylibre.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-08-12 13:22:17 +02:00
Rasmus Villemoes
9851ad2f71 Revert "gpio: mpc8xxx: change the gpio interrupt flags."
commit ec7099fdea8025988710ee6fecfd4e4210c29ab5 upstream.

This reverts commit 3d5bfbd9716318b1ca5c38488aa69f64d38a9aa5.

When booting with threadirqs, it causes a splat

  WARNING: CPU: 0 PID: 29 at kernel/irq/handle.c:159 __handle_irq_event_percpu+0x1ec/0x27c
  irq 66 handler irq_default_primary_handler+0x0/0x1c enabled interrupts

That splat later went away with commit 81e2073c175b ("genirq: Disable
interrupts for force threaded handlers"), which got backported to
-stable. However, when running an -rt kernel, the splat still
exists. Moreover, quoting Thomas Gleixner [1]

  But 3d5bfbd97163 ("gpio: mpc8xxx: change the gpio interrupt flags.")
  has nothing to do with that:

      "Delete the interrupt IRQF_NO_THREAD flags in order to gpio interrupts
       can be threaded to allow high-priority processes to preempt."

  This changelog is blatantly wrong. In mainline forced irq threads
  have always been invoked with softirqs disabled, which obviously
  makes them non-preemptible.

So the patch didn't even do what its commit log said.

[1] https://lore.kernel.org/lkml/871r8zey88.ffs@nanos.tec.linutronix.de/

Cc: stable@vger.kernel.org # v5.9+
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-08-12 13:22:16 +02:00
Kevin Hilman
57c44e7ac7 bus: ti-sysc: AM3: RNG is GP only
commit a6d90e9f22328f07343e49e08a4ca483ae8e8abb upstream.

Make the RNG on AM3 GP only.

Based on this patch from TI v5.4 tree which is based on hwmod data
which are now removed:

| ARM: AM43xx: hwmod: Move RNG to a GP only links table
|
| On non-GP devices the RNG is controlled by the secure-side software,
| like in DRA7xx hwmod we should not control this IP when we are not
| a GP device.
|
| Signed-off-by: Andrew F. Davis <afd@ti.com>

Cc: stable@vger.kernel.org # v5.10+
Signed-off-by: Kevin Hilman <khilman@baylibre.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-08-12 13:22:16 +02:00
Xiu Jianfeng
f4984f60ac selinux: correct the return value when loads initial sids
commit 4c156084daa8ee70978e4b150b5eb5fc7b1f15be upstream.

It should not return 0 when SID 0 is assigned to isids.
This patch fixes it.

Cc: stable@vger.kernel.org
Fixes: e3e0b582c321a ("selinux: remove unused initial SIDs and improve handling")
Signed-off-by: Xiu Jianfeng <xiujianfeng@huawei.com>
[PM: remove changelog from description]
Signed-off-by: Paul Moore <paul@paul-moore.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-08-12 13:22:16 +02:00
Zheyu Ma
100f8396d1 pcmcia: i82092: fix a null pointer dereference bug
commit e39cdacf2f664b09029e7c1eb354c91a20c367af upstream.

During the driver loading process, the 'dev' field was not assigned, but
the 'dev' field was referenced in the subsequent 'i82092aa_set_mem_map'
function.

Signed-off-by: Zheyu Ma <zheyuma97@gmail.com>
CC: <stable@vger.kernel.org>
[linux@dominikbrodowski.net: shorten commit message, add Cc to stable]
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-08-12 13:22:16 +02:00
Dmitry Safonov
afcd5a0e01 net/xfrm/compat: Copy xfrm_spdattr_type_t atributes
commit 4e9505064f58d1252805952f8547a5b7dbc5c111 upstream.

The attribute-translator has to take in mind maxtype, that is
xfrm_link::nla_max. When it is set, attributes are not of xfrm_attr_type_t.
Currently, they can be only XFRMA_SPD_MAX (message XFRM_MSG_NEWSPDINFO),
their UABI is the same for 64/32-bit, so just copy them.

Thanks to YueHaibing for reporting this:
In xfrm_user_rcv_msg_compat() if maxtype is not zero and less than
XFRMA_MAX, nlmsg_parse_deprecated() do not initialize attrs array fully.
xfrm_xlate32() will access uninit 'attrs[i]' while iterating all attrs
array.

KASAN: probably user-memory-access in range [0x0000000041b58ab0-0x0000000041b58ab7]
CPU: 0 PID: 15799 Comm: syz-executor.2 Tainted: G        W         5.14.0-rc1-syzkaller #0
RIP: 0010:nla_type include/net/netlink.h:1130 [inline]
RIP: 0010:xfrm_xlate32_attr net/xfrm/xfrm_compat.c:410 [inline]
RIP: 0010:xfrm_xlate32 net/xfrm/xfrm_compat.c:532 [inline]
RIP: 0010:xfrm_user_rcv_msg_compat+0x5e5/0x1070 net/xfrm/xfrm_compat.c:577
[...]
Call Trace:
 xfrm_user_rcv_msg+0x556/0x8b0 net/xfrm/xfrm_user.c:2774
 netlink_rcv_skb+0x153/0x420 net/netlink/af_netlink.c:2504
 xfrm_netlink_rcv+0x6b/0x90 net/xfrm/xfrm_user.c:2824
 netlink_unicast_kernel net/netlink/af_netlink.c:1314 [inline]
 netlink_unicast+0x533/0x7d0 net/netlink/af_netlink.c:1340
 netlink_sendmsg+0x86d/0xdb0 net/netlink/af_netlink.c:1929
 sock_sendmsg_nosec net/socket.c:702 [inline]

Fixes: 5106f4a8acff ("xfrm/compat: Add 32=>64-bit messages translator")
Cc: <stable@kernel.org>
Reported-by: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: Dmitry Safonov <dima@arista.com>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-08-12 13:22:16 +02:00
Frederic Weisbecker
f08b2d078c xfrm: Fix RCU vs hash_resize_mutex lock inversion
commit 2580d3f40022642452dd8422bfb8c22e54cf84bb upstream.

xfrm_bydst_resize() calls synchronize_rcu() while holding
hash_resize_mutex. But then on PREEMPT_RT configurations,
xfrm_policy_lookup_bytype() may acquire that mutex while running in an
RCU read side critical section. This results in a deadlock.

In fact the scope of hash_resize_mutex is way beyond the purpose of
xfrm_policy_lookup_bytype() to just fetch a coherent and stable policy
for a given destination/direction, along with other details.

The lower level net->xfrm.xfrm_policy_lock, which among other things
protects per destination/direction references to policy entries, is
enough to serialize and benefit from priority inheritance against the
write side. As a bonus, it makes it officially a per network namespace
synchronization business where a policy table resize on namespace A
shouldn't block a policy lookup on namespace B.

Fixes: 77cc278f7b20 (xfrm: policy: Use sequence counters with associated lock)
Cc: stable@vger.kernel.org
Cc: Ahmed S. Darwish <a.darwish@linutronix.de>
Cc: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Varad Gautam <varad.gautam@suse.com>
Cc: Steffen Klassert <steffen.klassert@secunet.com>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: David S. Miller <davem@davemloft.net>
Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-08-12 13:22:16 +02:00
Thomas Gleixner
23e36a8610 timers: Move clearing of base::timer_running under base:: Lock
commit bb7262b295472eb6858b5c49893954794027cd84 upstream.

syzbot reported KCSAN data races vs. timer_base::timer_running being set to
NULL without holding base::lock in expire_timers().

This looks innocent and most reads are clearly not problematic, but
Frederic identified an issue which is:

 int data = 0;

 void timer_func(struct timer_list *t)
 {
    data = 1;
 }

 CPU 0                                            CPU 1
 ------------------------------                   --------------------------
 base = lock_timer_base(timer, &flags);           raw_spin_unlock(&base->lock);
 if (base->running_timer != timer)                call_timer_fn(timer, fn, baseclk);
   ret = detach_if_pending(timer, base, true);    base->running_timer = NULL;
 raw_spin_unlock_irqrestore(&base->lock, flags);  raw_spin_lock(&base->lock);

 x = data;

If the timer has previously executed on CPU 1 and then CPU 0 can observe
base->running_timer == NULL and returns, assuming the timer has completed,
but it's not guaranteed on all architectures. The comment for
del_timer_sync() makes that guarantee. Moving the assignment under
base->lock prevents this.

For non-RT kernel it's performance wise completely irrelevant whether the
store happens before or after taking the lock. For an RT kernel moving the
store under the lock requires an extra unlock/lock pair in the case that
there is a waiter for the timer, but that's not the end of the world.

Reported-by: syzbot+aa7c2385d46c5eba0b89@syzkaller.appspotmail.com
Reported-by: syzbot+abea4558531bae1ba9fe@syzkaller.appspotmail.com
Fixes: 030dcdd197d7 ("timers: Prepare support for PREEMPT_RT")
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Link: https://lore.kernel.org/r/87lfea7gw8.fsf@nanos.tec.linutronix.de
Cc: stable@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-08-12 13:22:15 +02:00
Kajol Jain
9a69d0d24d fpga: dfl: fme: Fix cpu hotplug issue in performance reporting
commit ec6446d5304b3c3dd692a1e244df7e40bbb5af36 upstream.

The performance reporting driver added cpu hotplug
feature but it didn't add pmu migration call in cpu
offline function.
This can create an issue incase the current designated
cpu being used to collect fme pmu data got offline,
as based on current code we are not migrating fme pmu to
new target cpu. Because of that perf will still try to
fetch data from that offline cpu and hence we will not
get counter data.

Patch fixed this issue by adding pmu_migrate_context call
in fme_perf_offline_cpu function.

Fixes: 724142f8c42a ("fpga: dfl: fme: add performance reporting support")
Cc: stable@vger.kernel.org
Tested-by: Xu Yilun <yilun.xu@intel.com>
Acked-by: Wu Hao <hao.wu@intel.com>
Signed-off-by: Kajol Jain <kjain@linux.ibm.com>
Signed-off-by: Moritz Fischer <mdf@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-08-12 13:22:15 +02:00
Mario Kleiner
bfb5f1a123 serial: 8250_pci: Avoid irq sharing for MSI(-X) interrupts.
commit 341abd693d10e5f337a51f140ae3e7a1ae0febf6 upstream.

This attempts to fix a bug found with a serial port card which uses
an MCS9922 chip, one of the 4 models for which MSI-X interrupts are
currently supported. I don't possess such a card, and i'm not
experienced with the serial subsystem, so this patch is based on what
i think i found as a likely reason for failure, based on walking the
user who actually owns the card through some diagnostic.

The user who reported the problem finds the following in his dmesg
output for the relevant ttyS4 and ttyS5:

[    0.580425] serial 0000:02:00.0: enabling device (0000 -> 0003)
[    0.601448] 0000:02:00.0: ttyS4 at I/O 0x3010 (irq = 125, base_baud = 115200) is a ST16650V2
[    0.603089] serial 0000:02:00.1: enabling device (0000 -> 0003)
[    0.624119] 0000:02:00.1: ttyS5 at I/O 0x3000 (irq = 126, base_baud = 115200) is a ST16650V2
...
[    6.323784] genirq: Flags mismatch irq 128. 00000080 (ttyS5) vs. 00000000 (xhci_hcd)
[    6.324128] genirq: Flags mismatch irq 128. 00000080 (ttyS5) vs. 00000000 (xhci_hcd)
...

Output of setserial -a:

/dev/ttyS4, Line 4, UART: 16650V2, Port: 0x3010, IRQ: 127
	Baud_base: 115200, close_delay: 50, divisor: 0
	closing_wait: 3000
	Flags: spd_normal skip_test

This suggests to me that the serial driver wants to register and share a
MSI/MSI-X irq 128 with the xhci_hcd driver, whereas the xhci driver does
not want to share the irq, as flags 0x00000080 (== IRQF_SHARED) from the
serial port driver means to share the irq, and this mismatch ends in some
failed irq init?

With this setup, data reception works very unreliable, with dropped data,
already at a transmission rate of only a 16 Bytes chunk every 1/120th of
a second, ie. 1920 Bytes/sec, presumably due to rx fifo overflow due to
mishandled or not used at all rx irq's?

See full discussion thread with attempted diagnosis at:

https://psychtoolbox.discourse.group/t/issues-with-iscan-serial-port-recording/3886

Disabling the use of MSI interrupts for the serial port pci card did
fix the reliability problems. The user executed the following sequence
of commands to achieve this:

echo 0000:02:00.0 | sudo tee /sys/bus/pci/drivers/serial/unbind
echo 0000:02:00.1 | sudo tee /sys/bus/pci/drivers/serial/unbind

echo 0 | sudo tee /sys/bus/pci/devices/0000:02:00.0/msi_bus
echo 0 | sudo tee /sys/bus/pci/devices/0000:02:00.1/msi_bus

echo 0000:02:00.0 | sudo tee /sys/bus/pci/drivers/serial/bind
echo 0000:02:00.1 | sudo tee /sys/bus/pci/drivers/serial/bind

This resulted in the following log output:

[   82.179021] pci 0000:02:00.0: MSI/MSI-X disallowed for future drivers
[   87.003031] pci 0000:02:00.1: MSI/MSI-X disallowed for future drivers
[   98.537010] 0000:02:00.0: ttyS4 at I/O 0x3010 (irq = 17, base_baud = 115200) is a ST16650V2
[  103.648124] 0000:02:00.1: ttyS5 at I/O 0x3000 (irq = 18, base_baud = 115200) is a ST16650V2

This patch attempts to fix the problem by disabling irq sharing when
using MSI irq's. Note that all i know for sure is that disabling MSI
irq's fixed the problem for the user, so this patch could be wrong and
is untested. Please review with caution, keeping this in mind.

Fixes: 8428413b1d14 ("serial: 8250_pci: Implement MSI(-X) support")
Cc: Ralf Ramsauer <ralf.ramsauer@oth-regensburg.de>
Cc: stable <stable@vger.kernel.org>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Mario Kleiner <mario.kleiner.de@gmail.com>
Link: https://lore.kernel.org/r/20210729043306.18528-1-mario.kleiner.de@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-08-12 13:22:15 +02:00
Andy Shevchenko
0f30fedced serial: 8250_pci: Enumerate Elkhart Lake UARTs via dedicated driver
commit 7f0909db761535aefafa77031062603a71557267 upstream.

Elkhart Lake UARTs are PCI enumerated Synopsys DesignWare v4.0+ UART
integrated with Intel iDMA 32-bit DMA controller. There is a specific
driver to handle them, i.e. 8250_lpss. Hence, disable 8250_pci
enumeration for these UARTs.

Fixes: 1b91d97c66ef ("serial: 8250_lpss: Add ->setup() for Elkhart Lake ports")
Fixes: 4f912b898dc2 ("serial: 8250_lpss: Enable HS UART on Elkhart Lake")
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20210713101739.36962-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-08-12 13:22:15 +02:00
Maciej W. Rozycki
17f3c64f70 MIPS: Malta: Do not byte-swap accesses to the CBUS UART
commit 9a936d6c3d3d6c33ecbadf72dccdb567b5cd3c72 upstream.

Correct big-endian accesses to the CBUS UART, a Malta on-board discrete
TI16C550C part wired directly to the system controller's device bus, and
do not use byte swapping with the 32-bit accesses to the device.

The CBUS is used for devices such as the boot flash memory needed early
on in system bootstrap even before PCI has been initialised.  Therefore
it uses the system controller's device bus, which follows the endianness
set with the CPU, which means no byte-swapping is ever required for data
accesses to CBUS, unlike with PCI.

The CBUS UART uses the UPIO_MEM32 access method, that is the `readl' and
`writel' MMIO accessors, which on the MIPS platform imply byte-swapping
with PCI systems.  Consequently the wrong byte lane is accessed with the
big-endian configuration and the UART is not correctly accessed.

As it happens the UPIO_MEM32BE access method makes use of the `ioread32'
and `iowrite32' MMIO accessors, which still use `readl' and `writel'
respectively, however they byte-swap data passed, effectively cancelling
swapping done with the accessors themselves and making it suitable for
the CBUS UART.

Make the CBUS UART switch between UPIO_MEM32 and UPIO_MEM32BE then,
based on the endianness selected.  With this change in place the device
is correctly recognised with big-endian Malta at boot, along with the
Super I/O devices behind PCI:

Serial: 8250/16550 driver, 5 ports, IRQ sharing enabled
printk: console [ttyS0] disabled
serial8250.0: ttyS0 at I/O 0x3f8 (irq = 4, base_baud = 115200) is a 16550A
printk: console [ttyS0] enabled
printk: bootconsole [uart8250] disabled
serial8250.0: ttyS1 at I/O 0x2f8 (irq = 3, base_baud = 115200) is a 16550A
serial8250.0: ttyS2 at MMIO 0x1f000900 (irq = 20, base_baud = 230400) is a 16550A

Fixes: e7c4782f92fc ("[MIPS] Put an end to <asm/serial.h>'s long and annyoing existence")
Cc: stable@vger.kernel.org # v2.6.23+
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Maciej W. Rozycki <macro@orcam.me.uk>
Link: https://lore.kernel.org/r/alpine.DEB.2.21.2106260524430.37803@angie.orcam.me.uk
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-08-12 13:22:15 +02:00
Maciej W. Rozycki
8a1624f4a8 serial: 8250: Mask out floating 16/32-bit bus bits
commit e5227c51090e165db4b48dcaa300605bfced7014 upstream.

Make sure only actual 8 bits of the IIR register are used in determining
the port type in `autoconfig'.

The `serial_in' port accessor returns the `unsigned int' type, meaning
that with UPIO_AU, UPIO_MEM16, UPIO_MEM32, and UPIO_MEM32BE access types
more than 8 bits of data are returned, of which the high order bits will
often come from bus lines that are left floating in the data phase.  For
example with the MIPS Malta board's CBUS UART, where the registers are
aligned on 8-byte boundaries and which uses 32-bit accesses, data as
follows is returned:

YAMON> dump -32 0xbf000900 0x40

BF000900: 1F000942 1F000942 1F000900 1F000900  ...B...B........
BF000910: 1F000901 1F000901 1F000900 1F000900  ................
BF000920: 1F000900 1F000900 1F000960 1F000960  ...........`...`
BF000930: 1F000900 1F000900 1F0009FF 1F0009FF  ................

YAMON>

Evidently high-order 24 bits return values previously driven in the
address phase (the 3 highest order address bits used with the command
above are masked out in the simple virtual address mapping used here and
come out at zeros on the external bus), a common scenario with bus lines
left floating, due to bus capacitance.

Consequently when the value of IIR, mapped at 0x1f000910, is retrieved
in `autoconfig', it comes out at 0x1f0009c1 and when it is right-shifted
by 6 and then assigned to 8-bit `scratch' variable, the value calculated
is 0x27, not one of 0, 1, 2, 3 expected in port type determination.

Fix the issue then, by assigning the value returned from `serial_in' to
`scratch' first, which masks out 24 high-order bits retrieved, and only
then right-shift the resulting 8-bit data quantity, producing the value
of 3 in this case, as expected.  Fix the same issue in `serial_dl_read'.

The problem first appeared with Linux 2.6.9-rc3 which predates our repo
history, but the origin could be identified with the old MIPS/Linux repo
also at: <git://git.kernel.org/pub/scm/linux/kernel/git/ralf/linux.git>
as commit e0d2356c0777 ("Merge with Linux 2.6.9-rc3."), where code in
`serial_in' was updated with this case:

+	case UPIO_MEM32:
+		return readl(up->port.membase + offset);
+

which made it produce results outside the unsigned 8-bit range for the
first time, though obviously it is system dependent what actual values
appear in the high order bits retrieved and it may well have been zeros
in the relevant positions with the system the change originally was
intended for.  It is at that point that code in `autoconf' should have
been updated accordingly, but clearly it was overlooked.

Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Cc: stable@vger.kernel.org # v2.6.12+
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Maciej W. Rozycki <macro@orcam.me.uk>
Link: https://lore.kernel.org/r/alpine.DEB.2.21.2106260516220.37803@angie.orcam.me.uk
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-08-12 13:22:15 +02:00
Zhiyong Tao
c03cef6715 serial: 8250_mtk: fix uart corruption issue when rx power off
commit 7c4a509d3815a260c423c0633bd73695250ac26d upstream.

Fix uart corruption issue when rx power off.
Add spin lock in mtk8250_dma_rx_complete function in APDMA mode.

when uart is used as a communication port with external device(GPS).
when external device(GPS) power off, the power of rx pin is also from
1.8v to 0v. Even if there is not any data in rx. But uart rx pin can
capture the data "0".
If uart don't receive any data in specified cycle, uart will generates
BI(Break interrupt) interrupt.
If external device(GPS) power off, we found that BI interrupt appeared
continuously and very frequently.
When uart interrupt type is BI, uart IRQ handler(8250 framwork
API:serial8250_handle_irq) will push data to tty buffer.
mtk8250_dma_rx_complete is a task of mtk_uart_apdma_rx_handler.
mtk8250_dma_rx_complete priority is lower than uart irq
handler(serial8250_handle_irq).
if we are in process of mtk8250_dma_rx_complete, uart appear BI
interrupt:1)serial8250_handle_irq will priority execution.2)it may cause
write tty buffer conflict in mtk8250_dma_rx_complete.
So the spin lock protect the rx receive data process is not break.

Signed-off-by: Zhiyong Tao <zhiyong.tao@mediatek.com>
Cc: stable <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/20210729084640.17613-2-zhiyong.tao@mediatek.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-08-12 13:22:15 +02:00
Jon Hunter
a4f8bfc919 serial: tegra: Only print FIFO error message when an error occurs
commit cc9ca4d95846cbbece48d9cd385550f8fba6a3c1 upstream.

The Tegra serial driver always prints an error message when enabling the
FIFO for devices that have support for checking the FIFO enable status.
Fix this by displaying the error message, only when an error occurs.

Finally, update the error message to make it clear that enabling the
FIFO failed and display the error code.

Fixes: 222dcdff3405 ("serial: tegra: check for FIFO mode enabled status")
Cc: <stable@vger.kernel.org>
Acked-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Jon Hunter <jonathanh@nvidia.com>
Link: https://lore.kernel.org/r/20210630125643.264264-1-jonathanh@nvidia.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-08-12 13:22:14 +02:00
Theodore Ts'o
cc73007768 ext4: fix potential htree corruption when growing large_dir directories
commit 877ba3f729fd3d8ef0e29bc2a55e57cfa54b2e43 upstream.

Commit b5776e7524af ("ext4: fix potential htree index checksum
corruption) removed a required restart when multiple levels of index
nodes need to be split.  Fix this to avoid directory htree corruptions
when using the large_dir feature.

Cc: stable@kernel.org # v5.11
Cc: Благодаренко Артём <artem.blagodarenko@gmail.com>
Fixes: b5776e7524af ("ext4: fix potential htree index checksum corruption)
Reported-by: Denis <denis@voxelsoft.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-08-12 13:22:14 +02:00
Alex Xu (Hello71)
6b5a3d2c2b pipe: increase minimum default pipe size to 2 pages
commit 46c4c9d1beb7f5b4cec4dd90e7728720583ee348 upstream.

This program always prints 4096 and hangs before the patch, and always
prints 8192 and exits successfully after:

  int main()
  {
      int pipefd[2];
      for (int i = 0; i < 1025; i++)
          if (pipe(pipefd) == -1)
              return 1;
      size_t bufsz = fcntl(pipefd[1], F_GETPIPE_SZ);
      printf("%zd\n", bufsz);
      char *buf = calloc(bufsz, 1);
      write(pipefd[1], buf, bufsz);
      read(pipefd[0], buf, bufsz-1);
      write(pipefd[1], buf, 1);
  }

Note that you may need to increase your RLIMIT_NOFILE before running the
program.

Fixes: 759c01142a ("pipe: limit the per-user amount of pages allocated in pipes")
Cc: <stable@vger.kernel.org>
Link: https://lore.kernel.org/lkml/1628086770.5rn8p04n6j.none@localhost/
Link: https://lore.kernel.org/lkml/1628127094.lxxn016tj7.none@localhost/
Signed-off-by: Alex Xu (Hello71) <alex_y_xu@yahoo.ca>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-08-12 13:22:14 +02:00
Johan Hovold
556e7f204d media: rtl28xxu: fix zero-length control request
commit 76f22c93b209c811bd489950f17f8839adb31901 upstream.

The direction of the pipe argument must match the request-type direction
bit or control requests may fail depending on the host-controller-driver
implementation.

Control transfers without a data stage are treated as OUT requests by
the USB stack and should be using usb_sndctrlpipe(). Failing to do so
will now trigger a warning.

The driver uses a zero-length i2c-read request for type detection so
update the control-request code to use usb_sndctrlpipe() in this case.

Note that actually trying to read the i2c register in question does not
work as the register might not exist (e.g. depending on the demodulator)
as reported by Eero Lehtinen <debiangamer2@gmail.com>.

Reported-by: syzbot+faf11bbadc5a372564da@syzkaller.appspotmail.com
Reported-by: Eero Lehtinen <debiangamer2@gmail.com>
Tested-by: Eero Lehtinen <debiangamer2@gmail.com>
Fixes: d0f232e823af ("[media] rtl28xxu: add heuristic to detect chip type")
Cc: stable@vger.kernel.org      # 4.0
Cc: Antti Palosaari <crope@iki.fi>
Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Sean Young <sean@mess.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-08-12 13:22:14 +02:00
Filip Schauer
551e0c5d6b drivers core: Fix oops when driver probe fails
commit 4d1014c1816c0395eca5d1d480f196a4c63119d0 upstream.

dma_range_map is freed to early, which might cause an oops when
a driver probe fails.
 Call trace:
  is_free_buddy_page+0xe4/0x1d4
  __free_pages+0x2c/0x88
  dma_free_contiguous+0x64/0x80
  dma_direct_free+0x38/0xb4
  dma_free_attrs+0x88/0xa0
  dmam_release+0x28/0x34
  release_nodes+0x78/0x8c
  devres_release_all+0xa8/0x110
  really_probe+0x118/0x2d0
  __driver_probe_device+0xc8/0xe0
  driver_probe_device+0x54/0xec
  __driver_attach+0xe0/0xf0
  bus_for_each_dev+0x7c/0xc8
  driver_attach+0x30/0x3c
  bus_add_driver+0x17c/0x1c4
  driver_register+0xc0/0xf8
  __platform_driver_register+0x34/0x40
  ...

This issue is introduced by commit d0243bbd5dd3 ("drivers core:
Free dma_range_map when driver probe failed"). It frees
dma_range_map before the call to devres_release_all, which is too
early. The solution is to free dma_range_map only after
devres_release_all.

Fixes: d0243bbd5dd3 ("drivers core: Free dma_range_map when driver probe failed")
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Filip Schauer <filip@mg6.at>
Link: https://lore.kernel.org/r/20210727112311.GA7645@DESKTOP-E8BN1B0.localdomain
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-08-12 13:22:14 +02:00
Pavel Skripkin
faec2c68ea staging: rtl8712: error handling refactoring
commit e9e6aa51b2735d83a67d9fa0119cf11abef80d99 upstream.

There was strange error handling logic in case of fw load failure. For
some reason fw loader callback was doing clean up stuff when fw is not
available. I don't see any reason behind doing this. Since this driver
doesn't have EEPROM firmware let's just disconnect it in case of fw load
failure. Doing clean up stuff in 2 different place which can run
concurently is not good idea and syzbot found 2 bugs related to this
strange approach.

So, in this pacth I deleted all clean up code from fw callback and made
a call to device_release_driver() under device_lock(parent) in case of fw
load failure. This approach is more generic and it defend driver from UAF
bugs, since all clean up code is moved to one place.

Fixes: e02a3b945816 ("staging: rtl8712: fix memory leak in rtl871x_load_fw_cb")
Fixes: 8c213fa59199 ("staging: r8712u: Use asynchronous firmware loading")
Cc: stable <stable@vger.kernel.org>
Reported-and-tested-by: syzbot+5872a520e0ce0a7c7230@syzkaller.appspotmail.com
Reported-and-tested-by: syzbot+cc699626e48a6ebaf295@syzkaller.appspotmail.com
Signed-off-by: Pavel Skripkin <paskripkin@gmail.com>
Link: https://lore.kernel.org/r/d49ecc56e97c4df181d7bd4d240b031f315eacc3.1626895918.git.paskripkin@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-08-12 13:22:14 +02:00
Pavel Skripkin
e468a357af staging: rtl8712: get rid of flush_scheduled_work
commit 9be550ee43919b070bcd77f9228bdbbbc073245b upstream.

This patch is preparation for following patch for error handling
refactoring.

flush_scheduled_work() takes (wq_completion)events lock and
it can lead to deadlock when r871xu_dev_remove() is called from workqueue.
To avoid deadlock sutiation we can change flush_scheduled_work() call to
flush_work() call for all possibly scheduled works in this driver,
since next patch adds device_release_driver() in case of fw load failure.

Signed-off-by: Pavel Skripkin <paskripkin@gmail.com>
Cc: stable <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/6e028b4c457eeb7156c76c6ea3cdb3cb0207c7e1.1626895918.git.paskripkin@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-08-12 13:22:14 +02:00
Xiangyang Zhang
369101e399 staging: rtl8723bs: Fix a resource leak in sd_int_dpc
commit 990e4ad3ddcb72216caeddd6e62c5f45a21e8121 upstream.

The "c2h_evt" variable is not freed when function call
"c2h_evt_read_88xx" failed

Fixes: 554c0a3abf21 ("staging: Add rtl8723bs sdio wifi driver")
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Xiangyang Zhang <xyz.sun.ok@gmail.com>
Cc: stable <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/20210628152239.5475-1-xyz.sun.ok@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-08-12 13:22:13 +02:00
Tyler Hicks
1628b64efb tpm_ftpm_tee: Free and unregister TEE shared memory during kexec
commit dfb703ad2a8d366b829818a558337be779746575 upstream.

dma-buf backed shared memory cannot be reliably freed and unregistered
during a kexec operation even when tee_shm_free() is called on the shm
from a .shutdown hook. The problem occurs because dma_buf_put() calls
fput() which then uses task_work_add(), with the TWA_RESUME parameter,
to queue tee_shm_release() to be called before the current task returns
to user mode. However, the current task never returns to user mode
before the kexec completes so the memory is never freed nor
unregistered.

Use tee_shm_alloc_kernel_buf() to avoid dma-buf backed shared memory
allocation so that tee_shm_free() can directly call tee_shm_release().
This will ensure that the shm can be freed and unregistered during a
kexec operation.

Fixes: 09e574831b27 ("tpm/tpm_ftpm_tee: A driver for firmware TPM running inside TEE")
Fixes: 1760eb689ed6 ("tpm/tpm_ftpm_tee: add shutdown call back")
Cc: stable@vger.kernel.org
Signed-off-by: Tyler Hicks <tyhicks@linux.microsoft.com>
Reviewed-by: Sumit Garg <sumit.garg@linaro.org>
Acked-by: Jarkko Sakkinen <jarkko@kernel.org>
Signed-off-by: Jens Wiklander <jens.wiklander@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-08-12 13:22:13 +02:00
Allen Pais
2a879ff971 optee: fix tee out of memory failure seen during kexec reboot
commit f25889f93184db8b07a543cc2bbbb9a8fcaf4333 upstream.

The following out of memory errors are seen on kexec reboot
from the optee core.

[    0.368428] tee_bnxt_fw optee-clnt0: tee_shm_alloc failed
[    0.368461] tee_bnxt_fw: probe of optee-clnt0 failed with error -22

tee_shm_release() is not invoked on dma shm buffer.

Implement .shutdown() method to handle the release of the buffers
correctly.

More info:
https://github.com/OP-TEE/optee_os/issues/3637

Cc: stable@vger.kernel.org
Signed-off-by: Allen Pais <apais@linux.microsoft.com>
Reviewed-by: Tyler Hicks <tyhicks@linux.microsoft.com>
Reviewed-by: Jens Wiklander <jens.wiklander@linaro.org>
Reviewed-by: Sumit Garg <sumit.garg@linaro.org>
Signed-off-by: Jens Wiklander <jens.wiklander@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-08-12 13:22:13 +02:00
Tyler Hicks
ad80c25987 optee: Refuse to load the driver under the kdump kernel
commit adf752af454e91e123e85e3784972d166837af73 upstream.

Fix a hung task issue, seen when booting the kdump kernel, that is
caused by all of the secure world threads being in a permanent suspended
state:

 INFO: task swapper/0:1 blocked for more than 120 seconds.
       Not tainted 5.4.83 #1
 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
 swapper/0       D    0     1      0 0x00000028
 Call trace:
  __switch_to+0xc8/0x118
  __schedule+0x2e0/0x700
  schedule+0x38/0xb8
  schedule_timeout+0x258/0x388
  wait_for_completion+0x16c/0x4b8
  optee_cq_wait_for_completion+0x28/0xa8
  optee_disable_shm_cache+0xb8/0xf8
  optee_probe+0x560/0x61c
  platform_drv_probe+0x58/0xa8
  really_probe+0xe0/0x338
  driver_probe_device+0x5c/0xf0
  device_driver_attach+0x74/0x80
  __driver_attach+0x64/0xe0
  bus_for_each_dev+0x84/0xd8
  driver_attach+0x30/0x40
  bus_add_driver+0x188/0x1e8
  driver_register+0x64/0x110
  __platform_driver_register+0x54/0x60
  optee_driver_init+0x20/0x28
  do_one_initcall+0x54/0x24c
  kernel_init_freeable+0x1e8/0x2c0
  kernel_init+0x18/0x118
  ret_from_fork+0x10/0x18

The invoke_fn hook returned OPTEE_SMC_RETURN_ETHREAD_LIMIT, indicating
that the secure world threads were all in a suspended state at the time
of the kernel crash. This intermittently prevented the kdump kernel from
booting, resulting in a failure to collect the kernel dump.

Make kernel dump collection more reliable on systems utilizing OP-TEE by
refusing to load the driver under the kdump kernel.

Cc: stable@vger.kernel.org
Signed-off-by: Tyler Hicks <tyhicks@linux.microsoft.com>
Reviewed-by: Jens Wiklander <jens.wiklander@linaro.org>
Reviewed-by: Sumit Garg <sumit.garg@linaro.org>
Signed-off-by: Jens Wiklander <jens.wiklander@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-08-12 13:22:13 +02:00
Tyler Hicks
1340dc3fb7 optee: Fix memory leak when failing to register shm pages
commit ec185dd3ab257dc2a60953fdf1b6622f524cc5b7 upstream.

Free the previously allocated pages when we encounter an error condition
while attempting to register the pages with the secure world.

Fixes: a249dd200d03 ("tee: optee: Fix dynamic shm pool allocations")
Fixes: 5a769f6ff439 ("optee: Fix multi page dynamic shm pool alloc")
Cc: stable@vger.kernel.org
Signed-off-by: Tyler Hicks <tyhicks@linux.microsoft.com>
Reviewed-by: Jens Wiklander <jens.wiklander@linaro.org>
Reviewed-by: Sumit Garg <sumit.garg@linaro.org>
Signed-off-by: Jens Wiklander <jens.wiklander@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-08-12 13:22:13 +02:00
Jens Wiklander
6b2ded93d3 tee: add tee_shm_alloc_kernel_buf()
commit dc7019b7d0e188d4093b34bd0747ed0d668c63bf upstream.

Adds a new function tee_shm_alloc_kernel_buf() to allocate shared memory
from a kernel driver. This function can later be made more lightweight
by unnecessary dma-buf export.

Cc: stable@vger.kernel.org
Reviewed-by: Tyler Hicks <tyhicks@linux.microsoft.com>
Reviewed-by: Sumit Garg <sumit.garg@linaro.org>
Signed-off-by: Jens Wiklander <jens.wiklander@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-08-12 13:22:13 +02:00
Tyler Hicks
5e9d820214 optee: Clear stale cache entries during initialization
commit b5c10dd04b7418793517e3286cde5c04759a86de upstream.

The shm cache could contain invalid addresses if
optee_disable_shm_cache() was not called from the .shutdown hook of the
previous kernel before a kexec. These addresses could be unmapped or
they could point to mapped but unintended locations in memory.

Clear the shared memory cache, while being careful to not translate the
addresses returned from OPTEE_SMC_DISABLE_SHM_CACHE, during driver
initialization. Once all pre-cache shm objects are removed, proceed with
enabling the cache so that we know that we can handle cached shm objects
with confidence later in the .shutdown hook.

Cc: stable@vger.kernel.org
Signed-off-by: Tyler Hicks <tyhicks@linux.microsoft.com>
Reviewed-by: Jens Wiklander <jens.wiklander@linaro.org>
Reviewed-by: Sumit Garg <sumit.garg@linaro.org>
Signed-off-by: Jens Wiklander <jens.wiklander@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-08-12 13:22:13 +02:00
Mark Rutland
e5d8fd8709 arm64: stacktrace: avoid tracing arch_stack_walk()
commit 0c32706dac1b0a72713184246952ab0f54327c21 upstream.

When the function_graph tracer is in use, arch_stack_walk() may unwind
the stack incorrectly, erroneously reporting itself, missing the final
entry which is being traced, and reporting all traced entries between
these off-by-one from where they should be.

When ftrace hooks a function return, the original return address is
saved to the fgraph ret_stack, and the return address  in the LR (or the
function's frame record) is replaced with `return_to_handler`.

When arm64's unwinder encounter frames returning to `return_to_handler`,
it finds the associated original return address from the fgraph ret
stack, assuming the most recent `ret_to_hander` entry on the stack
corresponds to the most recent entry in the fgraph ret stack, and so on.

When arch_stack_walk() is used to dump the current task's stack, it
starts from the caller of arch_stack_walk(). However, arch_stack_walk()
can be traced, and so may push an entry on to the fgraph ret stack,
leaving the fgraph ret stack offset by one from the expected position.

This can be seen when dumping the stack via /proc/self/stack, where
enabling the graph tracer results in an unexpected
`stack_trace_save_tsk` entry at the start of the trace, and `el0_svc`
missing form the end of the trace.

This patch fixes this by marking arch_stack_walk() as notrace, as we do
for all other functions on the path to ftrace_graph_get_ret_stack().
While a few helper functions are not marked notrace, their calls/returns
are balanced, and will have no observable effect when examining the
fgraph ret stack.

It is possible for an exeption boundary to cause a similar offset if the
return address of the interrupted context was in the LR. Fixing those
cases will require some more substantial rework, and is left for
subsequent patches.

Before:

| # cat /proc/self/stack
| [<0>] proc_pid_stack+0xc4/0x140
| [<0>] proc_single_show+0x6c/0x120
| [<0>] seq_read_iter+0x240/0x4e0
| [<0>] seq_read+0xe8/0x140
| [<0>] vfs_read+0xb8/0x1e4
| [<0>] ksys_read+0x74/0x100
| [<0>] __arm64_sys_read+0x28/0x3c
| [<0>] invoke_syscall+0x50/0x120
| [<0>] el0_svc_common.constprop.0+0xc4/0xd4
| [<0>] do_el0_svc+0x30/0x9c
| [<0>] el0_svc+0x2c/0x54
| [<0>] el0t_64_sync_handler+0x1a8/0x1b0
| [<0>] el0t_64_sync+0x198/0x19c
| # echo function_graph > /sys/kernel/tracing/current_tracer
| # cat /proc/self/stack
| [<0>] stack_trace_save_tsk+0xa4/0x110
| [<0>] proc_pid_stack+0xc4/0x140
| [<0>] proc_single_show+0x6c/0x120
| [<0>] seq_read_iter+0x240/0x4e0
| [<0>] seq_read+0xe8/0x140
| [<0>] vfs_read+0xb8/0x1e4
| [<0>] ksys_read+0x74/0x100
| [<0>] __arm64_sys_read+0x28/0x3c
| [<0>] invoke_syscall+0x50/0x120
| [<0>] el0_svc_common.constprop.0+0xc4/0xd4
| [<0>] do_el0_svc+0x30/0x9c
| [<0>] el0t_64_sync_handler+0x1a8/0x1b0
| [<0>] el0t_64_sync+0x198/0x19c

After:

| # cat /proc/self/stack
| [<0>] proc_pid_stack+0xc4/0x140
| [<0>] proc_single_show+0x6c/0x120
| [<0>] seq_read_iter+0x240/0x4e0
| [<0>] seq_read+0xe8/0x140
| [<0>] vfs_read+0xb8/0x1e4
| [<0>] ksys_read+0x74/0x100
| [<0>] __arm64_sys_read+0x28/0x3c
| [<0>] invoke_syscall+0x50/0x120
| [<0>] el0_svc_common.constprop.0+0xc4/0xd4
| [<0>] do_el0_svc+0x30/0x9c
| [<0>] el0_svc+0x2c/0x54
| [<0>] el0t_64_sync_handler+0x1a8/0x1b0
| [<0>] el0t_64_sync+0x198/0x19c
| # echo function_graph > /sys/kernel/tracing/current_tracer
| # cat /proc/self/stack
| [<0>] proc_pid_stack+0xc4/0x140
| [<0>] proc_single_show+0x6c/0x120
| [<0>] seq_read_iter+0x240/0x4e0
| [<0>] seq_read+0xe8/0x140
| [<0>] vfs_read+0xb8/0x1e4
| [<0>] ksys_read+0x74/0x100
| [<0>] __arm64_sys_read+0x28/0x3c
| [<0>] invoke_syscall+0x50/0x120
| [<0>] el0_svc_common.constprop.0+0xc4/0xd4
| [<0>] do_el0_svc+0x30/0x9c
| [<0>] el0_svc+0x2c/0x54
| [<0>] el0t_64_sync_handler+0x1a8/0x1b0
| [<0>] el0t_64_sync+0x198/0x19c

Cc: <stable@vger.kernel.org>
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Madhavan T. Venkataraman <madvenka@linux.microsoft.com>
Cc: Mark Brown <broonie@kernel.org>
Cc: Will Deacon <will@kernel.org>
Reviwed-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20210802164845.45506-3-mark.rutland@arm.com
Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-08-12 13:22:12 +02:00
Mathieu Desnoyers
7799ad4d18 tracepoint: Fix static call function vs data state mismatch
commit 231264d6927f6740af36855a622d0e240be9d94c upstream.

On a 1->0->1 callbacks transition, there is an issue with the new
callback using the old callback's data.

Considering __DO_TRACE_CALL:

        do {                                                            \
                struct tracepoint_func *it_func_ptr;                    \
                void *__data;                                           \
                it_func_ptr =                                           \
                        rcu_dereference_raw((&__tracepoint_##name)->funcs); \
                if (it_func_ptr) {                                      \
                        __data = (it_func_ptr)->data;                   \

----> [ delayed here on one CPU (e.g. vcpu preempted by the host) ]

                        static_call(tp_func_##name)(__data, args);      \
                }                                                       \
        } while (0)

It has loaded the tp->funcs of the old callback, so it will try to use the old
data. This can be fixed by adding a RCU sync anywhere in the 1->0->1
transition chain.

On a N->2->1 transition, we need an rcu-sync because you may have a
sequence of 3->2->1 (or 1->2->1) where the element 0 data is unchanged
between 2->1, but was changed from 3->2 (or from 1->2), which may be
observed by the static call. This can be fixed by adding an
unconditional RCU sync in transition 2->1.

Note, this fixes a correctness issue at the cost of adding a tremendous
performance regression to the disabling of tracepoints.

Before this commit:

  # trace-cmd start -e all
  # time trace-cmd start -p nop

  real	0m0.778s
  user	0m0.000s
  sys	0m0.061s

After this commit:

  # trace-cmd start -e all
  # time trace-cmd start -p nop

  real	0m10.593s
  user	0m0.017s
  sys	0m0.259s

A follow up fix will introduce a more lightweight scheme based on RCU
get_state and cond_sync, that will return the performance back to what it
was. As both this change and the lightweight versions are complex on their
own, for bisecting any issues that this may cause, they are kept as two
separate changes.

Link: https://lkml.kernel.org/r/20210805132717.23813-3-mathieu.desnoyers@efficios.com
Link: https://lore.kernel.org/io-uring/4ebea8f0-58c9-e571-fd30-0ce4f6f09c70@samba.org/

Cc: stable@vger.kernel.org
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: "Paul E. McKenney" <paulmck@kernel.org>
Cc: Stefan Metzmacher <metze@samba.org>
Fixes: d25e37d89dd2 ("tracepoint: Optimize using static_call()")
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-08-12 13:22:12 +02:00
Mathieu Desnoyers
14673e1929 tracepoint: static call: Compare data on transition from 2->1 callees
commit f7ec4121256393e1d03274acdca73eb18958f27e upstream.

On transition from 2->1 callees, we should be comparing .data rather
than .func, because the same callback can be registered twice with
different data, and what we care about here is that the data of array
element 0 is unchanged to skip rcu sync.

Link: https://lkml.kernel.org/r/20210805132717.23813-2-mathieu.desnoyers@efficios.com
Link: https://lore.kernel.org/io-uring/4ebea8f0-58c9-e571-fd30-0ce4f6f09c70@samba.org/

Cc: stable@vger.kernel.org
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: "Paul E. McKenney" <paulmck@kernel.org>
Cc: Stefan Metzmacher <metze@samba.org>
Fixes: 547305a64632 ("tracepoint: Fix out of sync data passing by static caller")
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-08-12 13:22:12 +02:00