| CVE |
Vendors |
Products |
Updated |
CVSS v3.1 |
| In the Linux kernel, the following vulnerability has been resolved:
ocfs2: bound namelen in dlm_migrate_request_handler
Patch series "ocfs2/dlm: bound peer-controlled lengths in the o2dlm".
The o2dlm receive handlers trust u8 length and count fields from the wire
without bounding them, so a node in a DLM domain can corrupt or panic any
other node with a malformed message. Three defects:
- dlm_migrate_request_handler() passes migrate->namelen unchecked to
dlm_init_mle(), which memcpy()s it into the 32-byte mname[] of an
o2dlm_mle slab object: a heap out-of-bounds write of up to ~215
attacker-controlled bytes.
- dlm_mig_lockres_handler() passes mres->lockname_len unchecked to
dlm_init_lockres(), which memcpy()s it into the 32-byte o2dlm_lockname
slab object: a heap out-of-bounds write of up to ~223 bytes.
- the same handler trusts mres->num_locks without checking that the
message is large enough to hold that many entries, so
dlm_process_recovery_data() walks mres->ml[] past the kmalloc(data_len)
copy and trips a BUG_ON (an out-of-bounds read ending in a panic).
The other o2dlm receive handlers already reject an oversized name; the
migration and recovery handlers have omitted it since the DLM was added
(see the Fixes tags). Patch 1 bounds namelen; patch 2 validates
lockname_len, num_locks, and the payload size. Conforming recovery and
migration traffic is unaffected.
o2net authenticates peers only by the DLM domain key, so any node that has
joined the domain -- including a compromised or malicious member -- can
send these messages. There is no local trigger; the attacker must already
be a member of the cluster.
Each sink was confirmed under KASAN with an out-of-tree module mirroring
it exactly -- a kmem_cache/kmalloc of the real destination size, then the
same unclamped memcpy/loop: slab-out-of-bounds Write for the two writes,
Read for the recovery walk, and a panic. A userspace AddressSanitizer
build faults identically under -m32 and -m64. Scrubbed logs are available
on request.
I reported this privately to [email protected] and the ocfs2 maintainers
on 2026-06-20; with no response after the standard embargo period I am
posting the fix publicly. I have no embargo requirement.
This patch (of 2):
A node receiving a DLM_MIGRATE_REQUEST message trusts the peer-supplied
name length (migrate->namelen) without bounding it. dlm_init_mle() then
copies that many bytes into the fixed DLM_LOCKID_NAME_MAX-byte mname[]
array of an o2dlm_mle slab object, so a malformed message from a cluster
peer overflows the slab object by up to ~215 bytes: a heap out-of-bounds
write of attacker-controlled data, reachable by any node in the domain.
Reject an oversized name, the way dlm_master_request_handler() and the
other o2dlm receive handlers already do; the migration handler omits the
check entirely. Conforming messages are unaffected. |
| In the Linux kernel, the following vulnerability has been resolved:
ocfs2: validate lengths in dlm_mig_lockres_handler
A node receiving a DLM_MIG_LOCKRES message trusts several fields of the
peer-supplied dlm_migratable_lockres without validation. num_locks and
lockname_len are bounded only on the sending side, and the message is
never checked to actually carry num_locks migratable_lock entries. As a
result dlm_process_recovery_data() walks mres->ml[0..num_locks) past the
kmalloc(data_len) copy of the message (an out-of-bounds read that ends in
a BUG_ON panic), and dlm_init_lockres() copies lockname_len bytes into the
fixed 32-byte o2dlm_lockname slab object (a heap out-of-bounds write).
Both are reachable by any node in the domain.
Validate these fields right after dlm_grab(), before anything uses them --
including the not-joined error path, which already prints mres->lockname
with the unbounded lockname_len as a %.*s precision. Reject the message
unless lockname_len <= DLM_LOCKID_NAME_MAX, num_locks <=
DLM_MAX_MIGRATABLE_LOCKS (the bound the sender already asserts), and the
payload is large enough to hold the claimed locks. Conforming recovery
and migration messages are unaffected. |
| In the Linux kernel, the following vulnerability has been resolved:
ocfs2: validate rl_used against rl_count in refcount block validator
ocfs2_find_refcount_rec_in_rl() walks the on-disk refcount record array
with:
for (; i < le16_to_cpu(rb->rf_records.rl_used); i++) {
rec = &rb->rf_records.rl_recs[i];
...
rl_recs[] lives in a single metadata block (4096 bytes on the common
configuration), so its real capacity is fixed by
ocfs2_refcount_recs_per_rb(sb) (247 records for a 4K block with the
16-byte ocfs2_refcount_rec). rl_used and rl_count are both read directly
off disk by ocfs2_validate_refcount_block() and are never checked against
that capacity, nor against each other, before any refcount/reflink/CoW
operation walks the array.
A crafted (or corrupted) refcount block with rl_used == 0xffff makes the
loop above walk far past the end of the block, dereferencing rl_recs[i]
for i up to 65534. The resulting index is then handed to the sibling
ocfs2_insert_refcount_rec(), whose insert-shift does:
if (index < le16_to_cpu(rf_list->rl_used))
memmove(&rf_list->rl_recs[index + 1],
&rf_list->rl_recs[index],
(le16_to_cpu(rf_list->rl_used) - index) *
sizeof(struct ocfs2_refcount_rec));
i.e. a memmove() of up to (0xffff - index) * 16 bytes (~1 MiB) from an
offset already past the block. This is reachable from an ordinary reflink
(FICLONE) against a crafted/corrupted ocfs2 image: attaching an extent
whose cpos sorts past every real record in the leaf forces the lookup to
run off the end instead of returning early on a match. The attacker model
is local: CAP_SYS_ADMIN mounting a crafted or corrupted ocfs2 image, or a
raw write to the block device backing an already-mounted ocfs2 filesystem.
ocfs2_validate_refcount_block() already validates the block's ECC,
signature, rf_blkno and rf_fs_generation, but never rl_count/rl_used
against the block's actual on-disk capacity. This is the same class of
gap that ocfs2_validate_extent_block() (fs/ocfs2/alloc.c) already closes
for the sibling extent-list header, which checks both the record capacity
and the "used" bound before any code walks h_list.l_recs[]:
if (le16_to_cpu(eb->h_list.l_count) != ocfs2_extent_recs_per_eb(sb)) {
rc = ocfs2_error(...);
goto bail;
}
if (le16_to_cpu(eb->h_list.l_next_free_rec) >
le16_to_cpu(eb->h_list.l_count)) {
rc = ocfs2_error(...);
goto bail;
}
Add the equivalent pair of checks to ocfs2_validate_refcount_block():
reject a refcount block whose rl_count does not match the fixed per-block
capacity returned by ocfs2_refcount_recs_per_rb(), and reject rl_used >
rl_count. Both checks are skipped when OCFS2_REFCOUNT_TREE_FL is set,
because in that case the same union bytes hold an ocfs2_extent_list
(rf_list), not the refcount record list (rf_records) -- that layout is
already validated separately by ocfs2_validate_extent_block() when the
referenced extent block is read. This mirrors the existing
"!(rb->rf_flags & OCFS2_REFCOUNT_TREE_FL)" guard used elsewhere in this
file (e.g. ocfs2_get_refcount_rec()) to decide whether rf_records or
rf_list is the live member of the union.
With this in place, a forged rl_used/rl_count is caught at block
validation time (ocfs2_error()), consistent with every other corruption
check in this function, instead of driving an out-of-bounds read in
ocfs2_find_refcount_rec_in_rl() and a subsequent out-of-bounds memmove()
in ocfs2_insert_refcount_rec().
Verified against a crafted image on a v6.19 KASAN (KASAN_GENERIC) build:
replaying the same reflink (FICLONE) reliably hit a KASAN report in
__ocfs2_increase_refcount()/ocfs2_insert_refcount_rec() before this patch,
and triggers no report once ocfs2_validate_refcount_block() rejects the
forged rl_used/rl_count. |
| In the Linux kernel, the following vulnerability has been resolved:
ocfs2: cluster: don't sleep while holding o2hb_live_lock in o2hb_region_pin()
Patch series "ocfs2: cluster: o2hb_region_pin() fixes", v2.
This series fixes three related issues in o2hb_region_pin(), all are from
the original implementation in commit: 58a3158a5d17 ("ocfs2/cluster:
Pin/unpin o2hb regions"):
1) It is called with o2hb_live_lock (a spinlock) held, but the
underlying configfs_depend_item() sleeps (takes inode rwsem and
pins the filesystem). This triggers BUG under
CONFIG_DEBUG_ATOMIC_SLEEP.
2) When called from the configfs drop_item callback, it creates a
lock order inversion: parent inode_lock -> configfs root
inode_lock, which can deadlock against subsystem unregistration
paths taking root -> parent.
3) If pinning fails partway through o2hb_region_inc_user(), the
o2hb_dependent_users counter is leaked and partially-pinned
regions are never released, leaving heartbeat regions
unprotected on subsequent mounts.
Patch 1 reworks o2hb_region_pin() to drop o2hb_live_lock across each
sleeping configfs_depend_item() call, using a config_item reference to
keep the region alive while unlocked.
Patch 2 adds a from_callback parameter to select
configfs_depend_item_unlocked() when called from configfs context,
avoiding the inode_lock nesting.
Patch 3 fixes the error path in o2hb_region_inc_user() to unpin and
decrement the counter on failure.
This patch (of 3):
o2hb_region_pin() is always called with the o2hb_live_lock spinlock held
(from o2hb_region_inc_user() and o2hb_heartbeat_group_drop_item()), but it
calls o2nm_depend_item() -> configfs_depend_item(), which sleeps: it pins
the configfs filesystem and takes the configfs root inode rwsem. Under
CONFIG_DEBUG_ATOMIC_SLEEP this triggers:
BUG: sleeping function called from invalid context at kernel/locking/rwsem.c
in_atomic(): 1, ... name: mount.ocfs2
down_write
configfs_depend_item
o2hb_region_pin
o2hb_region_inc_user
o2hb_register_callback
dlm_register_domain_handlers
...
ocfs2_dlm_init
ocfs2_mount_volume
ocfs2_fill_super
Rework o2hb_region_pin() to pin one region at a time with the lock dropped
across the sleeping call: under o2hb_live_lock find the next eligible
region and take a config_item reference to keep it alive, drop the lock,
call o2nm_depend_item(), then retake the lock and record the pin. The
config_item_put() is done with the lock released as well, since
o2hb_region_release() also acquires o2hb_live_lock and can sleep. The
region list may change while unlocked, so the scan restarts from the top
after each pin. Local heartbeat still pins only the matching region;
global heartbeat pins all eligible regions.
The unpin path is unaffected: configfs_undepend_item() only takes a
spinlock and does not sleep. |
| In the Linux kernel, the following vulnerability has been resolved:
ocfs2: fix readdir position truncation on 32-bit kernels
In ocfs2_dir_foreach_blk_el(), the directory cookie position is
rebuilt with
ctx->pos = (ctx->pos & ~(sb->s_blocksize - 1)) | offset;
`ctx->pos` is loff_t (signed 64-bit), while `sb->s_blocksize` is
unsigned long. On 32-bit kernels unsigned long is 32-bit, so the mask
~(sb->s_blocksize - 1)
is computed as a 32-bit unsigned value (e.g. 0xfffff000 for a 4 KiB
block size). In the AND expression with the 64-bit `ctx->pos`, that
unsigned operand is zero-extended to 64 bits per the usual arithmetic
conversions, yielding 0x00000000fffff000. The high 32 bits of
`ctx->pos` are silently cleared, even though directory size is
allowed to exceed 4 GiB.
When readdir() crosses the 4 GiB boundary on a 32-bit kernel the
position is reset back into the first 4 GiB block, making the
re-validation path re-enumerate already-returned dirents indefinitely.
This is ocfs2_dir_foreach_blk_el(), the extent-list readdir path taken
for all non-inline directories, so a directory large enough to cross
4 GiB reaches it.
This is the same class of bug that commit 3dce5bb82c97 ("exfat: Fix
bitwise operation having different size") fixed in exfat, and the
fix mirrors the equivalent ext4 fix in this series. Cast the operand
to loff_t so the mask is 64-bit before the AND:
ctx->pos = (ctx->pos & ~((loff_t)sb->s_blocksize - 1)) | offset;
64-bit kernels are unaffected. |
| In the Linux kernel, the following vulnerability has been resolved:
openrisc: fix arbitrary kernel memory access via or1k_atomic syscall
sys_or1k_atomic() (syscall 244 in the "or1k" ABI) takes two user
pointers, v1 and v2, and swaps the words they point to in hand-written
assembly.
l.lwz r29,0(r4)
l.lwz r27,0(r5)
l.sw 0(r4),r27
l.sw 0(r5),r29
The pointers are not checked with access_ok(). The four memory
accesses also have no exception table entries.
A caller passes a kernel address as either pointer, and the syscall
reads from and writes to it directly.
This gives an unprivileged process a kernel read/write primitive. It
overwrites kernel data such as the sys_call_table, gaining code
execution in kernel context.
Check both pointers before entering the critical section. Add fixups
for the four memory accesses so faults on valid but unmapped user
addresses return -EFAULT.
[[email protected]: fix comment style] |
| In the Linux kernel, the following vulnerability has been resolved:
lockd: pin next file across nlm_inspect_file lock-drop
nlm_traverse_files() pins the current file with f_count++ across
a mutex_unlock for nlm_inspect_file(), but nothing pins the saved
next pointer. A concurrent nlm_release_file() can kfree the next
file during the unlock window, and the iterator dereferences freed
memory on the next loop step.
Pin both current and next before the lock-drop. Advance by
swapping the pinned cursors at the end of each iteration so next
is always held alive across the unlock.
Always call nlm_file_release() after dropping the iteration pin,
regardless of whether the file matched the predicate. Use
nlm_file_inuse(), which does a live walk of the inode lock list,
rather than the cached f_locks field, so skipped files that never
ran nlm_inspect_file() are evaluated correctly.
Because every file in a hash bucket is now pinned and released,
files skipped by the is_failover_file predicate that have no
locks, blocks, shares, or external references are deleted during
traversal. The old code never evaluated skipped files for
cleanup. The new behavior is intentional: such files are stale
and should not persist in the table. |
| In the Linux kernel, the following vulnerability has been resolved:
power: supply: bq24257: fix use-after-free on remove
The STAT-pin interrupt is devm-managed, so it stays armed until the devm
cleanup that runs after remove() returns. remove() cancels
bq->iilimit_setup_work while the threaded handler can still fire; that
handler reschedules the work and dereferences bq, so the work runs
against freed memory once devm frees bq.
Make the delayed work device-managed with devm_delayed_work_autocancel(),
registered before the interrupt request. The devm cleanup then releases
the interrupt first, so the handler can no longer reschedule the work,
and cancels the work before bq is freed. The explicit
cancel_delayed_work_sync() in remove() is no longer needed and is dropped.
Found by static analysis. |
| In the Linux kernel, the following vulnerability has been resolved:
power: supply: bq256xx: drain usb_work before freeing the charger
The USB-PHY notifier queues usb_work, whose handler calls
power_supply_changed(bq->charger). The reset devm action only unregisters
the notifier and was registered before the power supplies, so devm frees
bq->charger on unwind before the action runs; a usb_work still queued can
then dereference it.
Register the reset action after the power supplies, so it unregisters
the notifiers and drains usb_work before the supplies are released.
Initialize usb_work and obtain the PHY references before registering
the notifiers, so the worker cannot run before the supplies exist.
Found by static analysis. |
| In the Linux kernel, the following vulnerability has been resolved:
power: supply: bq25890: Fix power_supply reference leak
bq25890_fw_probe() acquires a reference to a secondary charger using
power_supply_get_by_name(), but the reference is not released on later
probe failures or on driver detach.
In particular, failures after bq25890_fw_probe() returns successfully,
such as a failure in bq25890_hw_init(), also leak the reference.
Register a device-managed cleanup action immediately after acquiring
the secondary charger. This releases the reference on all subsequent
probe failures and on driver detach.
Found by code review. |
| In the Linux kernel, the following vulnerability has been resolved:
power: supply: cros_usbpd-charger: bound the EC-reported port count
cros_usbpd_charger_probe() reads two port counts from the EC and uses
one of them, num_charger_ports, as the loop bound when populating a
fixed-size array:
struct port_data *ports[EC_USB_PD_MAX_PORTS]; /* 8 entries */
...
for (i = 0; i < charger->num_charger_ports; i++)
charger->ports[charger->num_registered_psy++] = port;
Both num_usbpd_ports (from EC_CMD_USB_PD_PORTS) and num_charger_ports
(from EC_CMD_CHARGE_PORT_COUNT) are u8 values reported by the EC. The
only validation is a sanity check that compares the two EC-reported
values against each other:
if (num_charger_ports < num_usbpd_ports ||
num_charger_ports > num_usbpd_ports + 1)
return -EPROTO;
It never checks either count against EC_USB_PD_MAX_PORTS, the size of
the ports[] array. A malfunctioning, malicious or compromised EC that
reports num_usbpd_ports == num_charger_ports == N for any N > 8 (for
example both 255) passes this check, and the loop then writes N pointers
into the 8-entry ports[] array embedded in the devm_kzalloc()'d
charger_data, overflowing it by up to 255 - 8 = 247 entries (~1976
bytes): a slab out-of-bounds write.
Reject a port count larger than the ports[] array can hold. |
| In the Linux kernel, the following vulnerability has been resolved:
power: supply: cros_usbpd: Limit port counts to EC_USB_PD_MAX_PORTS
Currently the cros_usbpd-charger driver probe iterates based on raw
charger port count returned by the embedded controller. The only check
is against the number of USB PD ports which the embedded controller
also defines. A malicious embedded controller could return an inaccurate
port count (up to 255) resulting in an out of bounds write and
subsequent memory corruption.
Update helper functions in cros_usbpd-charger to limit port counts to
EC_USB_PD_MAX_PORTS. |
| In the Linux kernel, the following vulnerability has been resolved:
power: supply: lp8727: fix use-after-free in lp8727_release_irq()
lp8727_isr_func(), the threaded IRQ handler, is the only caller that arms
pchg->work via schedule_delayed_work(). lp8727_release_irq() currently
cancels the work before freeing the IRQ, so an IRQ delivered in between
can re-arm the work through the threaded handler. After .remove returns
the devm layer frees pchg while lp8727_delayed_func() may still run and
dereference it.
Free the IRQ first so the threaded handler is quiesced and can no longer
queue work, then cancel the delayed work to drain the final generation.
This issue was found by an in-house static analysis tool. |
| In the Linux kernel, the following vulnerability has been resolved:
power: supply: qcom_battmgr: terminate the strings from firmware
The qcom_battmgr_sc8280xp_strcpy() takes a Pascal-style string when the
firmware sends one. Otherwise it copies all BATTMGR_STRING_LEN bytes and
leaves the destination without a terminator.
Those destinations are model_number, serial_number and oem_info, each
BATTMGR_STRING_LEN and declared next to each other. They go out to user
space as val->strval, which power_supply_format_property() prints with
"%s", so a firmware string that fills the whole field makes that read run
into the following members.
Use strscpy() so the copy always terminates, the way the SM8350 path
already does for the same field. |
| In the Linux kernel, the following vulnerability has been resolved:
power: supply: rt9455: quiesce delayed work before teardown
The threaded IRQ handler can queue pwr_rdy_work,
max_charging_time_work and batt_presence_work. pwr_rdy_work and
batt_presence_work can also queue max_charging_time_work, while
batt_presence_work can requeue itself.
rt9455_remove() cancels max_charging_time_work before
batt_presence_work. The latter can therefore queue
max_charging_time_work after it has already been cancelled:
rt9455_remove() workqueue
cancel pwr_rdy_work
cancel max_charging_time_work
batt_presence_work queues
max_charging_time_work
cancel batt_presence_work
return
devres frees rt9455_info
max_charging_time_work dereferences
rt9455_info
The IRQ also remains registered until devres cleanup and can queue more
work after any of the cancellation calls. If rt9455_hw_init() fails
after the IRQ has been requested, probe returns without cancelling work
that may already have been queued. A pending callback can then access
rt9455_info after it has been freed.
Register rt9455_cancel_all_delayed_works() through
devm_add_action_or_reset() right after devm_power_supply_register().
devres invokes the action in reverse registration order, after the
managed IRQ has been freed and before rt9455_info is released, so the
delayed works are drained in both rt9455_remove() and the probe error
path. Cancel pwr_rdy_work and batt_presence_work before
max_charging_time_work because both can queue the latter.
This issue was found by an in-house static analysis tool. |
| In the Linux kernel, the following vulnerability has been resolved:
power: supply: twl4030_charger: cancel workers via devm
bci is devm-allocated. Two workers (bci->work and bci->current_worker)
dereference it. twl4030_bci_remove() disables charging and masks
interrupts. It cancels neither worker. A worker pending at remove() can
run after devm frees bci.
The USB transceiver comes from devm_usb_get_phy_by_node(). devm
unregisters its notifier only after remove() returns. A cancel_work_sync()
in remove() can then race a notifier reschedule. devm_work_autocancel()
and devm_delayed_work_autocancel() avoid that. They cancel the workers
during devm release, before bci is freed.
The current_worker is registered first, since devm will cancel in
reverse order and bci->work can reschedule current_worker.
[Move comment about order into the commit message] |
| In the Linux kernel, the following vulnerability has been resolved:
power: supply: ucs1002: fix use-after-free on remove
ucs1002 has no remove callback, so unbind runs entirely through devm.
The alert IRQ handler queues the health_poll delayed work, and the work
reschedules itself while the chip reports a bad-health condition. devm
frees the alert IRQ, which only synchronizes the handler; it does not
cancel the delayed work, which can then run after devm frees the driver
data and dereference it.
Register health_poll with devm_delayed_work_autocancel() before the
alert IRQ is requested. devm then frees the IRQ before cancelling the
work, so the handler can no longer queue it and the work is cancelled
before the driver data is freed.
This issue was found by an in-house static analysis tool. |
| In the Linux kernel, the following vulnerability has been resolved:
power: supply: max17040: synchronize work cancellation on suspend
max17040_work() requeues itself after every poll. cancel_delayed_work()
only cancels a pending instance and does not wait for a callback that is
already running.
If system suspend races with the polling callback, the callback can
continue accessing the fuel gauge and requeue itself after the suspend
callback returns.
Use cancel_delayed_work_sync() to ensure polling is quiesced before
suspend completes. |
| In the Linux kernel, the following vulnerability has been resolved:
s390/cpum_cf: Handle CPU hotplug via prepare/dead callbacks
The command 'perf stat -e cycles -- <command>' crashes the kernel
when CPUs are hotplug added during that run.
Root cause is the allocation of struct cpu_cf_events at first
event initialization. The allocation is dynamic and the first
event that has task context creates such a structure for
each online CPU. This is not sufficient. CPUs may be offline
during event creation and can be set online during the
perf run time. For example commands
# echo 0 > /sys/devices/system/cpu/cpu1/online
# perf stat -e cycles -i -- stress-ng -t10s --matrix X
# sleep 1
# echo 1 > /sys/devices/system/cpu/cpu1/online
create an event for CPUs 0,2-X. Since the events are created with
task-context, the scheduler will eventually schedule the program
on CPU1. This CPU has not created and initialized any per
CPU event infrastructure as that CPU was not online at the time
of the perf invocation. Thus when the scheduler runs stress-ng
on CPU1, the function cpumf_pmu_add() refers to a NULL pointer:
struct cpu_cf_events *cpuhw = this_cpu_cfhw();
This function call is invoked after the task stress-ng has been
made runnable on CPU1. And this_cpu_cfhw() returns NULL.
The result is a panic:
Unable to handle kernel pointer dereference in virtual kernel address space
Failing address: 0000000000000000 TEID: 0000000000000483
....
Krnl PSW : 0404d00180000000 000003ef8291fd0c (cpumf_pmu_add+0x3c/0x80)
....
Call Trace:
[<000003ef8291fd0c>] cpumf_pmu_add+0x3c/0x80
[<000003ef82bb5e3e>] event_sched_in+0xae/0x190
[<000003ef82bb60d6>] merge_sched_in+0x1b6/0x390
[<000003ef82bb65b8>] visit_groups_merge.constprop.0.isra.0+0x308/0x5b0
[<000003ef82bb689a>] pmu_groups_sched_in+0x3a/0x50
[<000003ef82bb6a30>] ctx_sched_in+0x180/0x260
[<000003ef82bb780c>] perf_event_context_sched_in+0x11c/0x2d0
[<000003ef82bb79ee>] __perf_event_task_sched_in+0x2e/0xc0
[<000003ef82994834>] finish_task_switch.isra.0+0x1a4/0x250
....
Last Breaking-Event-Address:
[<000003ef8291f1d8>] this_cpu_cfhw+0x38/0x40
The issue arises only in per-task context when the CPUMF facility is
used and the scheduler picks a random CPU for such a process to run on.
The scheduler enables the CPUMF infrastructure via PMU callback
functions pmu::add() and pmu::del().
Introduce a CPU hotplug prepare/dead callback pair which creates and
removes the per CPU counter data while the CPU is offline. Count the
users which track every CPU (cpu == -1), that is perf_event_open()
events with task context and /dev/hwctr device sessions, in the new
counter cpu_cf_root::tskcnt, protected by pmc_reserve_mutex.
This ensures the infrastructure is available when
new CPU is selected to run the per-task context process.
In cpum_cf_free_root() and cpum_cf_free_cpu() ensure the reference
pointer to data structures is set to NULL before the data is freed
to prevent interrupt handlers to access stale data.
[[email protected]: change commit message] |
| In the Linux kernel, the following vulnerability has been resolved:
s390/dasd: Do not complete a failed ESE read as successful
dasd_int_handler() completes an NRF read of an unallocated ESE track by
calling ese_read() and unconditionally marking the request
DASD_CQR_SUCCESS. dasd_eckd_ese_read() can return an error before it has
zeroed the destination buffer: a failed sense-data parse or a current
track outside the requested range both return early, leaving the
destination pages untouched. The request is still completed successfully,
so the block layer is handed stale / uninitialized memory instead of
zeros.
Check the ese_read() return value and fail the request through the normal
error path instead of forcing DASD_CQR_SUCCESS. |
