In the Linux kernel, the following vulnerability has been resolved:
PCI: endpoint: Add missing NULL check for alloc_workqueue()
alloc_workqueue() can return NULL on memory allocation failure. Without
proper error checking, this may lead to a NULL pointer dereference when
queue_work() is later called with the NULL workqueue pointer in
epf_ntb_epc_init().
Add a NULL check immediately after alloc_workqueue() and return -ENOMEM on
failure to prevent the driver from loading with an invalid workqueue
pointer.
In the Linux kernel, the following vulnerability has been resolved:
eventpoll: fix ep_remove struct eventpoll / struct file UAF
ep_remove() (via ep_remove_file()) cleared file->f_ep under
file->f_lock but then kept using @file inside the critical section
(is_file_epoll(), hlist_del_rcu() through the head, spin_unlock).
A concurrent __fput() taking the eventpoll_release() fastpath in
that window observed the transient NULL, skipped
eventpoll_release_file() and ran to f_op->release / file_free().
For the epoll-watches-epoll case, f_op->release is
ep_eventpoll_release() -> ep_clear_and_put() -> ep_free(), which
kfree()s the watched struct eventpoll. Its embedded ->refs
hlist_head is exactly where epi->fllink.pprev points, so the
subsequent hlist_del_rcu()'s "*pprev = next" scribbles into freed
kmalloc-192 memory.
In addition, struct file is SLAB_TYPESAFE_BY_RCU, so the slot
backing @file could be recycled by alloc_empty_file() --
reinitializing f_lock and f_ep -- while ep_remove() is still
nominally inside that lock. The upshot is an attacker-controllable
kmem_cache_free() against the wrong slab cache.
Pin @file via epi_fget() at the top of ep_remove() and gate the
critical section on the pin succeeding. With the pin held @file
cannot reach refcount zero, which holds __fput() off and
transitively keeps the watched struct eventpoll alive across the
hlist_del_rcu() and the f_lock use, closing both UAFs.
If the pin fails @file has already reached refcount zero and its
__fput() is in flight. Because we bailed before clearing f_ep,
that path takes the eventpoll_release() slow path into
eventpoll_release_file() and blocks on ep->mtx until the waiter
side's ep_clear_and_put() drops it. The bailed epi's share of
ep->refcount stays intact, so the trailing ep_refcount_dec_and_test()
in ep_clear_and_put() cannot free the eventpoll out from under
eventpoll_release_file(); the orphaned epi is then cleaned up
there.
A successful pin also proves we are not racing
eventpoll_release_file() on this epi, so drop the now-redundant
re-check of epi->dying under f_lock. The cheap lockless
READ_ONCE(epi->dying) fast-path bailout stays.
In the Linux kernel, the following vulnerability has been resolved:
spi: ch341: fix devres lifetime
USB drivers bind to USB interfaces and any device managed resources
should have their lifetime tied to the interface rather than parent USB
device. This avoids issues like memory leaks when drivers are unbound
without their devices being physically disconnected (e.g. on probe
deferral or configuration changes).
Fix the controller and driver data lifetime so that they are released
on driver unbind.
Note that this also makes sure that the SPI controller is placed
correctly under the USB interface in the device tree.
In the Linux kernel, the following vulnerability has been resolved:
spi: cadence-quadspi: fix unclocked access on unbind
Make sure that the controller is runtime resumed before disabling it
during driver unbind to avoid an unclocked register access.
This issue was flagged by Sashiko when reviewing a controller
deregistration fix.
In the Linux kernel, the following vulnerability has been resolved:
f2fs: fix fsck inconsistency caused by FGGC of node block
During FGGC node block migration, fsck may incorrectly treat the
migrated node block as fsync-written data.
The reproduction scenario:
root@vm:/mnt/f2fs# seq 1 2048 | xargs -n 1 ./test_sync // write inline inode and sync
root@vm:/mnt/f2fs# rm -f 1
root@vm:/mnt/f2fs# sync
root@vm:/mnt/f2fs# f2fs_io gc_range // move data block in sync mode and not write CP
SPO, "fsck --dry-run" find inode has already checkpointed but still
with DENT_BIT_SHIFT set
The root cause is that GC does not clear the dentry mark and fsync mark
during node block migration, leading fsck to misinterpret them as
user-issued fsync writes.
In BGGC mode, node block migration is handled by f2fs_sync_node_pages(),
which guarantees the dentry and fsync marks are cleared before writing.
This patch move the set/clear of the fsync|dentry marks into
__write_node_folio to make the logic clearer, and ensures the
fsync|dentry mark is cleared in FGGC.
In the Linux kernel, the following vulnerability has been resolved:
RDMA/mlx4: Fix mis-use of RCU in mlx4_srq_event()
Sashiko points out the radix_tree itself is RCU safe, but nothing ever
frees the mlx4_srq struct with RCU, and it isn't even accessed within the
RCU critical section. It also will crash if an event is delivered before
the srq object is finished initializing.
Use the spinlock since it isn't easy to make RCU work, use
refcount_inc_not_zero() to protect against partially initialized objects,
and order the refcount_set() to be after the srq is fully initialized.
In the Linux kernel, the following vulnerability has been resolved:
riscv: kvm: fix vector context allocation leak
When the second kzalloc (host_context.vector.datap) fails in
kvm_riscv_vcpu_alloc_vector_context, the first allocation
(guest_context.vector.datap) is leaked. Free it before returning.
In the Linux kernel, the following vulnerability has been resolved:
KVM: arm64: Fix pin leak and publication ordering in __pkvm_init_vcpu()
Two bugs exist in the vCPU initialisation path:
1. If a check fails after hyp_pin_shared_mem() succeeds, the cleanup
path jumps to 'unlock' without calling unpin_host_vcpu() or
unpin_host_sve_state(), permanently leaking pin references on the
host vCPU and SVE state pages.
Extract a register_hyp_vcpu() helper that performs the checks and
the store. When register_hyp_vcpu() returns an error, call
unpin_host_vcpu() and unpin_host_sve_state() inline before falling
through to the existing 'unlock' label.
2. register_hyp_vcpu() publishes the new vCPU pointer into
'hyp_vm->vcpus[]' with a bare store, allowing a concurrent caller
of pkvm_load_hyp_vcpu() to observe a partially initialised vCPU
object.
Ensure the store uses smp_store_release() and the load uses
smp_load_acquire(). While 'vm_table_lock' currently serialises the
store and the load, these barriers ensure the reader sees the fully
initialised 'hyp_vcpu' object even if there were a lockless path or
if the lock's own ordering guarantees were insufficient for nested
object initialization.
In the Linux kernel, the following vulnerability has been resolved:
spi: microchip-core-qspi: control built-in cs manually
The coreQSPI IP supports only a single chip select, which is
automagically operated by the hardware - set low when the transmit
buffer first gets written to and set high when the number of bytes
written to the TOTALBYTES field of the FRAMES register have been sent on
the bus. Additional devices must use GPIOs for their chip selects.
It was reported to me that if there are two devices attached to this
QSPI controller that the in-built chip select is set low while linux
tries to access the device attached to the GPIO.
This went undetected as the boards that connected multiple devices to
the SPI controller all exclusively used GPIOs for chip selects, not
relying on the built-in chip select at all. It turns out that this was
because the built-in chip select, when controlled automagically, is set
low when active and high when inactive, thereby ruling out its use for
active-high devices or devices that need to transmit with the chip
select disabled.
Modify the driver so that it controls chip select directly, retaining
the behaviour for mem_ops of setting the chip select active for the
entire duration of the transfer in the exec_op callback. For regular
transfers, implement the set_cs callback for the core to use.
As part of this, the existing setup callback, mchp_coreqspi_setup_op(),
is removed. Modifying the CLKIDLE field is not safe to do during
operation when there are multiple devices, so this code is removed
entirely. Setting the MASTER and ENABLE fields is something that can be
done once at probe, it doesn't need to be re-run for each device.
Instead the new setup callback sets the built-in chip select to its
inactive state for active-low devices, as the reset value of the chip
select in software controlled mode is low.
In the Linux kernel, the following vulnerability has been resolved:
8021q: delete cleared egress QoS mappings
vlan_dev_set_egress_priority() currently keeps cleared egress
priority mappings in the hash as tombstones. Repeated set/clear cycles
with distinct skb priorities therefore accumulate mapping nodes until
device teardown and leak memory.
Delete mappings when vlan_prio is cleared instead of keeping tombstones.
Now that the egress mapping lists are RCU protected, the node can be
unlinked safely and freed after a grace period.