| CVE |
Vendors |
Products |
Updated |
CVSS v3.1 |
| In the Linux kernel, the following vulnerability has been resolved:
x86/mm/pat: Acquire init_mm write lock on collapse to avoid UAF
x86 implements page attribute modification using its Change Page
Attributes (CPA) mechanism.
This tracks properties of ranges such as cache mode through x86 page
attributes, and as part of that logic manipulates kernel page tables.
Since commit:
41d88484c71c ("x86/mm/pat: restore large ROX pages after fragmentation")
ranges of kernel page table entries can be collapsed into
huge page table entries as part of this logic.
As part of this collapse, it frees the page tables which the collapsed
entries previously pointed to, and it does so without any relevant locks
being held to preclude concurrent kernel page table walkers.
The only way this code can be reached is if CPA_COLLAPSE is specified, and
this is only set in set_memory_rox() via:
set_memory_rox()
-> change_page_attr_set_clr()
-> cpa_flush()
-> cpa_collapse_large_pages()
Notable users of this are execmem and BPF when manipulating executable
mappings.
However, this is problematic for ptdump as it walks ranges it does not own
and thus runs the risk of a use-after-free on page tables freed underneath
it.
In addition, concurrent CPA collapse operations are possible which can also
cause races.
Resolve the issue by acquiring the mmap write lock on init_mm across the
whole operation.
It is safe to acquire a sleeping lock as all the callers invoke
set_memory_rox() from process context and in any case,
change_page_attr_set_clr() calls vm_unmap_alias() which ultimately takes a
mutex, disallowing atomic context here. |
| In the Linux kernel, the following vulnerability has been resolved:
accel: ethosu: Ensure SRAM size is 0 on mapping failure
On a mapping failure of the SRAM, the SRAM size is left as non-zero. The
probe will succeed as the error return is not checked since having SRAM is
not a hard requirement. The non-zero size allows jobs to access SRAM which
is left pointing to physical base address 0x0. |
| In the Linux kernel, the following vulnerability has been resolved:
mm/slab: take n->list_lock in __slab_try_return_freelist() to avoid race
Commit ba7425312607 ("mm, slab: add an optimistic
__slab_try_return_freelist()") incorrectly assumed that nobody has freed
an object to the slab as long as slab->freelist is NULL and cmpxchg
succeeds.
However, as reported by Hyunwoo Kim [1], other CPUs might have freed
an object to the slab, insert the slab to the partial list, then
allocated an object from the slab, and be in the middle of removing
the slab from the list under n->list_lock.
Since __refill_objects_node() puts the slab back on pc.slabs
outside n->list_lock, it might insert the slab into that list while
the slab is concurrently being removed from n->partial.
This led to a list corruption [1]:
list_add corruption. next->prev should be prev
(ffff888100000248), but was dead000000000122.
(next=ffffea000416e410).
kernel BUG at lib/list_debug.c:29!
Oops: invalid opcode: 0000 [#1] SMP NOPTI
CPU: 1 UID: 65534 PID: 144 Comm: poc Not tainted
7.2.0-16172-gcf72cbb39da8-dirty #1 PREEMPT(lazy)
RIP: 0010:__list_add_valid_or_report+0x80/0xd0
...
Call Trace:
alloc_from_new_slab+0x183/0x300
___slab_alloc+0x31c/0x890
__kmalloc_noprof+0x3d4/0x800
lsm_blob_alloc+0x2d/0x50
security_msg_msg_alloc+0x26/0x90
load_msg+0x1aa/0x210
do_msgsnd+0x91/0x800
do_syscall_64+0x109/0x5d0
entry_SYSCALL_64_after_hwframe+0x77/0x7f
...
Kernel panic - not syncing: Fatal exception
This is a classic ABA problem where cmpxchg succeeds but the state has
changed since __refill_objects_node() took the freelist from the slab.
As Vlastimil Babka mentioned [2], it should be rare to return more than
one slab (due to the racy read of slab->counters in
get_partial_node_bulk()). Therefore, instead of introducing additional
complexity, acquire and release n->list_lock twice in the worst case.
Return the slab directly to the partial list and hold n->list_lock
across the cmpxchg and add_partial(). This is similar to the initial
version of commit ba7425312607 [3]. This is enough to avoid the race as
the list manipulation is serialized by n->list_lock. While at it,
bring back unlikely() hint now that the condition is unlikely. |
| In the Linux kernel, the following vulnerability has been resolved:
x86/cfi: Fix FineIBT hash offset in cfi_get_func_hash()
The switch of the FineIBT preamble from "subl $hash, %r10d" to the
shorter "subl $hash, %eax" moved the hash immediate from offset 7 to
offset 5 of the preamble. fineibt_preamble_hash was updated to match,
but the open-coded offset in cfi_get_func_hash() was missed and it
still reads the hash at offset 7.
cfi_get_func_hash() is used by the BPF JIT to give a struct_ops
trampoline the CFI hash of the stub function it stands in for. With
FineIBT the trampoline now gets the upper half of the real hash
followed by the first two bytes of the next instruction, so the first
indirect call from the kernel into a struct_ops program,
tcp_init_congestion_control() calling ->init() of a BPF congestion
control for example, fails the FineIBT check and the kernel dies with
a CFI failure.
Move the FineIBT preamble template and its offset defines above
cfi_get_func_hash() and use fineibt_preamble_hash there, so every
reader of the preamble shares one definition of its layout. The
CFI_FINEIBT arm is only built with CONFIG_FINEIBT, the only
configuration in which cfi_mode can take that value.
cfi_get_func_arity() does not need the same treatment: the __bhi_args
call whose displacement it reads still ends at the function address. |
| In the Linux kernel, the following vulnerability has been resolved:
x86/amd_node: Fix PCI device reference counting in amd_smn_init()
The local "root" pointer is a temporary variable used during the device
search. Therefore, refcount related to the search iterators should be cleaned
up after the search is complete.
Use the __free() cleanup macro to ensure the refcount is decremented when the
temporary pointer goes out of scope.
Additionally, increment the refcount when caching a root pointer. This ensures
the in-use refcount is separate from the temporary search refcounting.
Finally, drop the redundant "root = NULL" before the second search loop. The
pci_get_class() iterator always decrements the refcount of its "from"
argument, so the first loop can only fall through with "root" already NULL. |
| In the Linux kernel, the following vulnerability has been resolved:
net: mana: restore the XDP program pointer when pre-allocation fails
mana_xdp_set() publishes the new program into apc->bpf_prog before it
allocates anything, because mana_pre_alloc_rxbufs() sizes the buffers
from it via mana_get_rxbuf_cfg(). When that allocation fails the
function returns the error directly, skipping the err_dealloc_rxbuffs
label which is the only place that restores the previous pointer.
The attach is reported as failed, so the BPF core drops the reference it
held for the caller and the program can be freed, while apc->bpf_prog
still points at it. The next consumer of mana_xdp_get() - typically
mana_chn_setxdp() from mana_alloc_queues() on the following ifup, or
after a TX timeout reset - then calls bpf_prog_add() on freed memory.
This is reachable from an ordinary "ip link set dev ethX xdp obj ..."
whenever the per-queue RX buffer pre-allocation cannot be satisfied.
Restore the previous program on that error path. |
| In the Linux kernel, the following vulnerability has been resolved:
net: hsr: free learned nodes on device setup failure
hsr_dev_finalize() can fail after a lower-device RX handler has
already been registered (slave A is added before the failable slave B
and interlink adds). RX handlers run in softirq regardless of the
master's state, so frames received in that window can learn dynamic
nodes into node_db, and the error unwind never releases them.
Free both owned dynamic databases in the unwind, mirroring
hsr_dellink(). proxy_node_db is provably empty on every current error
exit (only interlink RX feeds it, and the interlink add is the last
failable step) and is freed for symmetry. The order is safe:
hsr_del_port() unregisters each RX handler with synchronize_net()
before hsr_del_nodes() runs, which removes remaining entries with
list_del_rcu() and defers their release with call_rcu() for readers
already under RCU. |
| In the Linux kernel, the following vulnerability has been resolved:
hwmon: (corsair-cpro) Remove debugfs entries when probe fails
ccp_debugfs_init() registers debugfs files whose private data is the devm
allocated ccp. If hwmon_device_register_with_info() fails right after it,
ccp_probe() returns without removing them: the HID core then frees ccp,
and ccp_remove() is not called for a failed probe, so the files stay
behind. Reading one of them dereferences the freed pointer.
Remove the debugfs entries on that error path. debugfs_remove_recursive()
waits for readers already inside the show callbacks, so ccp is no longer
reachable through debugfs by the time probe returns. |
| In the Linux kernel, the following vulnerability has been resolved:
nstree: check listing permission before taking a namespace reference
legitimize_ns() takes a reference on the candidate namespace before
may_list_ns() has decided whether the caller may see it. The
__free(ns_put) cleanup on the denied path can drop the last reference to a
mount namespace while we still hold the rcu read lock, and put_mnt_ns()
may sleep there. This is the same problem commit 2ec2aff3c8e2 ("ns: make
sure reference are dropped outside of rcu lock") fixed for the put_user()
path. Neither ns_requested() nor may_list_ns() needs a reference, both
only look at the namespace type and at the caller's own namespaces, so do
the checks first and take the reference last.
Splat:
Voluntary context switch within RCU read-side critical section!
WARNING: kernel/rcu/tree_plugin.h:332 at rcu_note_context_switch+0x238/0x2a0, CPU#5: a/3442
CPU: 5 UID: 1000 PID: 3442 Comm: a Not tainted 7.0.0-30-generic #30-Ubuntu PREEMPT(lazy)
RIP: 0010:rcu_note_context_switch+0x238/0x2a0
Call Trace:
<TASK>
__schedule+0xcf/0x650
schedule+0x27/0x90
schedule_preempt_disabled+0x15/0x30
__mutex_lock.constprop.0+0x550/0xaf0
__mutex_lock_slowpath+0x13/0x20
mutex_lock+0x3b/0x50
exp_funnel_lock+0xb2/0x260
synchronize_rcu_expedited+0xe7/0x220
namespace_unlock+0x26a/0x320
put_mnt_ns+0xd3/0x120
mntns_put+0xe/0x20
do_listns+0x13e/0x560
__do_sys_listns+0x126/0x2d0
__x64_sys_listns+0x20/0x30
x64_sys_call+0x2366/0x2390
do_syscall_64+0x105/0x5a0
entry_SYSCALL_64_after_hwframe+0x76/0x7e
</TASK> |
| In the Linux kernel, the following vulnerability has been resolved:
net: macb: put the "mdio" child node reference on success
macb_mii_init() holds the reference returned by of_get_child_by_name()
for macb_mdiobus_register() and drops it only on the error paths, so
every successful probe leaks a node reference. On a CM5, overlay
removal after four bind cycles reports
OF: ERROR: memory leak, expected refcount 1 instead of 5
Drop the reference after registration, where __mdiobus_register() has
already taken its own for the lifetime of the bus. |
| In the Linux kernel, the following vulnerability has been resolved:
vduse: return compat ioctl results directly
The compat handler handles VDUSE_IOTLB_GET_FD and VDUSE_VQ_GET_INFO, but
then calls the native handler. Their different command sizes make native
dispatch return -ENOIOCTLCMD.
For GET_FD, this overwrites receive_fd()'s return value after the
descriptor is installed, leaking one fd per call. Return handled compat
results directly and use native dispatch only for other commands. |
| In the Linux kernel, the following vulnerability has been resolved:
hwmon: (corsair-cpro) Create debugfs entries after hwmon registration
ccp_debugfs_init() registers debugfs files whose private data is the devm
allocated ccp. It runs before hwmon_device_register_with_info(), so when
that registration fails, ccp_probe() returns with the files still in
place. The HID core then frees ccp, and ccp_remove() is not called for a
failed probe, so nothing removes them later either. Reading one of the
files dereferences the freed pointer.
Create the debugfs entries only after the hwmon device has been
registered, so no failing path can leave them behind.
The two version queries stay where they are. They send USB commands
without holding ccp->mutex, which is only safe as long as nothing else
can call send_usb_cmd(); once the hwmon device is registered its
callbacks can do so concurrently. Only the debugfs creation moves, and
it is told which queries succeeded. |
| In the Linux kernel, the following vulnerability has been resolved:
ext4: fix transaction overflow during writeback
Commit 95ad8ee45cdb ("ext4: correct the reserved credits for extent
conversion") was correct to note that we need to reserve enough credits
for all extents possibly underlying a large folio. However it was too
eager to reduce the number of reserved credits. Extent conversion may
not only need to touch several leaf extent blocks, it may also need to
split extents - for example a single large unwritten extent may need to
be split into many small written ones in case of sparse folio dirtying.
This can thus result not only in extent leaf modifications but also in a
need to allocate new extent tree nodes. As a result the reserved
transaction credits were not sufficient in some corner cases. Use
ext4_meta_trans_blocks() for correct upper bound credit estimate. |
| In the Linux kernel, the following vulnerability has been resolved:
virtio: fix use-after-free in unregister_virtio_device()
device_unregister() is device_del() plus put_device(). When the caller
holds no extra reference, that drops the last one and runs the release
callback, which for several transports frees the memory the embedded
struct virtio_device sits in. unregister_virtio_device() then calls
virtio_debug_device_exit(), which reads dev->debugfs_dir out of the freed
object.
Affected transports are the ones whose release callback frees and whose
remove path takes no reference: virtio_mmio, virtio_vdpa, virtio_uml,
mlxbf-tmfifo and virtio_ccw. virtio_pci is unaffected because
virtio_pci_remove() brackets the call with get_device() and put_device().
Remove the debugfs entries before the device can go away. They are only
accessed through the protected debugfs interface, so
debugfs_remove_recursive() waits for in-progress file operations before
returning. Tearing them down while the device is still alive is therefore
safe.
Reproduced on User-Mode Linux with CONFIG_KASAN and CONFIG_VIRTIO_DEBUG
by unbinding a virtio-uml device:
BUG: KASAN: slab-use-after-free in virtio_debug_device_exit+0x36/0x4d
Read of size 8 at addr 00000000616e0b10 by task init/1
__asan_report_load8_noabort
virtio_debug_device_exit+0x36/0x4d
unregister_virtio_device+0x48/0x75
virtio_uml_remove
platform_remove
device_release_driver_internal
unbind_store
Freed by task 1:
kfree
virtio_uml_release_dev
device_release
kobject_put
put_device
device_unregister
With this applied, the report is gone and unbind is clean. |
| In the Linux kernel, the following vulnerability has been resolved:
bpf: Mark faultable stack helpers as sleepable
The faultable variants of bpf_get_stack() and bpf_get_task_stack() pass
may_fault=true into the common stack collection code. Resolving user-space
build IDs may then call build_id_parse_file() and block on filesystem
reads.
Neither helper prototype sets might_sleep. Since prototype selection uses
the sleepability of the whole program, the verifier can still allow these
helpers from a non-sleepable region within that program, such as an
explicit RCU or preemption-disabled region. The task-stack helper can also
be called from a non-sleepable timer callback of a sleepable program.
Mark both faultable prototypes as sleepable. The existing helper context
check then rejects these calls while continuing to allow them in genuinely
sleepable contexts. |
| In the Linux kernel, the following vulnerability has been resolved:
hwmon: Fix potential UAF in pec_store
Sashiko reports:
In pec_store(), a guard(mutex)(&hwdev->lock) is taken. If the chip write
operation returns an error other than -EOPNOTSUPP, the code jumps to the
put label, which calls put_device(hdev). If this drops the final reference,
the device is freed. When the function then returns, the guard cleanup
function runs and attempts to unlock the freed mutex.
Use scoped_guard() instead of guard() to avoid the problem. |
| In the Linux kernel, the following vulnerability has been resolved:
iommu/amd: Fix ineffective error check in nested domain allocation
amd_iommu_pdom_id_alloc() returns an int: a domain ID on success, or the
negative errno from ida_alloc_range() when the ID space is exhausted or
memory is short. amd_iommu_alloc_domain_nested() stores that return value
in gdom_info->hdom_id, which is a u32, and only then tests it:
gdom_info->hdom_id = amd_iommu_pdom_id_alloc();
if (gdom_info->hdom_id <= 0) {
The assignment discards the sign, so -ENOSPC becomes 0xffffffe4 and the
test never fires. The nested domain is then set up with a host domain ID
that was never allocated, instead of the allocation failing with -ENOSPC.
Keep the value in an int, test it there, and store it only once it is
known to be valid, which is what the other amd_iommu_pdom_id_alloc()
callers already do. |
| In the Linux kernel, the following vulnerability has been resolved:
erofs: delimit inode_share cache key components
Previously, inode_share keys were encoded as follows:
fingerprint || domain_id
It would be better to have a separator between the fingerprint and domain
ID so that the fingerprint won't be parsed as part of a domain ID.
Change the key encoding as follows:
domain_id || '\0' || fingerprint
Since domain_id is a NUL-terminated string, this makes the in-memory key
indices unambiguous. |
| In the Linux kernel, the following vulnerability has been resolved:
net: mctp: i3c: serialize probe with bus removal
mctp_i3c_probe() drops busdevs_lock after finding the matching bus. A
concurrent I3C_NOTIFY_BUS_REMOVE can then unregister and free the bus
netdev before probe passes its private data to mctp_i3c_add_device().
The latter consequently adds a list node through a freed mbus pointer.
Keep busdevs_lock held until the device has been added. This also
satisfies the __must_hold annotation on mctp_i3c_add_device(). |
| In the Linux kernel, the following vulnerability has been resolved:
hwmon: (ltc4282) Make sure clk_init_data is fully initialized
The clk_init_data structure contains several mutually-exclusive members
for different methods to specify the possible parents of a clock,
prompting drivers to initialize only the members they need. However,
not initializing all members may cause subtle issues, which are only
exposed when CONFIG_INIT_STACK_ALL_PATTERN or CONFIG_INIT_STACK_NONE is
enabled.
ltc428_clk_provider_setup() does not fill in any parent clocks, and
assumes that init.num_parents is NULL. However, the latter in
uninitialized, and thus may cause a crash.
Make sure all members are fully initialized, to fix such bugs, and to
avoid future breakage when converting drivers to a different method for
specifying the parents. |
