| CVE |
Vendors |
Products |
Updated |
CVSS v3.1 |
| In the Linux kernel, the following vulnerability has been resolved:
netfs: Fix folio->private handling in netfs_perform_write()
Under some circumstances, netfs_perform_write() doesn't correctly
manipulate folio->private between NULL, NETFS_FOLIO_COPY_TO_CACHE, pointing
to a group and pointing to a netfs_folio struct, leading to potential
multiple attachments of private data with associated folio ref leaks and
also leaks of netfs_folio structs or netfs_group refs.
Fix this by consolidating the place at which a folio is marked uptodate in
one place and having that look at what's attached to folio->private and
decide how to clean it up and then set the new group. Also, the content
shouldn't be flushed if group is NULL, even if a group is specified in the
netfs_group parameter, as that would be the case for a new folio. A
filesystem should always specify netfs_group or never specify netfs_group.
The Sashiko auto-review tool noted that it was theoretically possible that
the fpos >= ctx->zero_point section might leak if it modified a streaming
write folio. This is unlikely, but with a network filesystem, third party
changes can happen. It also pointed out that __netfs_set_group() would
leak if called multiple times on the same folio from the "whole folio
modify section". |
| In the Linux kernel, the following vulnerability has been resolved:
Bluetooth: L2CAP: fix chan ref leak in l2cap_chan_timeout() on !conn
__set_chan_timer() takes a l2cap_chan reference via l2cap_chan_hold()
before scheduling the delayed work. The normal path in
l2cap_chan_timeout() drops this reference with l2cap_chan_put() at the
end, but the early return when chan->conn is NULL skips the put,
leaking the reference.
Add the missing l2cap_chan_put() before the early return. |
| In the Linux kernel, the following vulnerability has been resolved:
accel/amdxdna: Fix mm_struct reference leak in aie2_populate_range()
aie2_populate_range() jumps back to the again label without calling
mmput(mm), leaking a reference to the mm_struct.
Add the missing mmput() before jumping to again. |
| In the Linux kernel, the following vulnerability has been resolved:
xfrm: input: hold netns during deferred transport reinjection
Transport-mode reinjection stores a struct net pointer in skb->cb and
uses it later from xfrm_trans_reinject(). That pointer must stay valid
until the deferred callback runs.
Take a netns reference when queueing deferred reinjection work and drop
it after the callback completes. Use maybe_get_net() so the queueing
path does not revive a namespace that is already being torn down.
This keeps the existing workqueue design and fixes the netns lifetime
handling in one place for all users of xfrm_trans_queue_net(). |
| In the Linux kernel, the following vulnerability has been resolved:
mm/rmap: initialize nr_pages to 1 at loop start in try_to_unmap_one
Initialize nr_pages to 1 at the start of each loop iteration, like
folio_referenced_one() does.
Without this, nr_pages computed by a previous folio_unmap_pte_batch() call
can be reused on a later iteration that does not run
folio_unmap_pte_batch() again.
mmap a 64K large folio with MAP_ANONYMOUS | MAP_DROPPABLE, then call
madvise(MADV_FREE), then make the last page device-exclusive via
HMM_DMIRROR_EXCLUSIVE.
Trigger node reclaim through sysfs. Now, in try_to_unmap_one(), we will
first clear the first 15 out of 16 entries mapping the lazyfree folio.
This will set nr_pages to 15. In the next pvmw walk, this nr_pages gets
reused on a device-exclusive pte, thus potentially corrupting folio
refcount/mapcount.
At the moment, I have a userspace program which can make the kernel spit
out a trace, but the blow up is in folio_referenced_one(), because there
are existing bugs in the interaction between device-private and rmap
(which too I am investigating). I did a one liner kernel change to avoid
going into folio_referenced_one(), and the kernel blows up at
folio_remove_rmap_ptes in try_to_unmap_one which is what I wanted.
Note that the bug is there not since file folio batching but lazyfree
folio batching, since device-exclusive only works for anonymous folios.
Userspace visible effect is simply kernel crashing somewhere due to
refcount/mapcount corruption. |
| In the Linux kernel, the following vulnerability has been resolved:
esp: fix page frag reference leak on skb_to_sgvec failure
In esp_output_tail(), when esp->inplace is false, the old skb page frags
are replaced with a new page from the xfrm page_frag cache. The source
scatterlist (sg) is built from the old frags before the replacement, and
esp_ssg_unref() is responsible for releasing the old page references
after the crypto operation completes.
However, if the second skb_to_sgvec() call (which builds the destination
scatterlist from the new page) fails, the code jumps to error_free which
only calls kfree(tmp). The old page frag references captured in the
source scatterlist are never released:
1. sg[] is built from old frags via skb_to_sgvec() (no extra get_page)
2. nr_frags is set to 1 and frag[0] is replaced with the new page
3. Second skb_to_sgvec() fails -> goto error_free
4. kfree(tmp) frees the sg[] memory but old frags are not unref'd
5. kfree_skb() only releases frag[0] (the new page), not the old ones
Fix this by adding a bool parameter to esp_ssg_unref() that, when true,
unconditionally unrefs the source scatterlist frags without checking
req->src and req->dst, since those fields are not yet initialized by
aead_request_set_crypt() at the point of the error. Existing callers
pass false to preserve the original behavior.
The same issue exists in both esp4 and esp6 as the code is identical. |
| In the Linux kernel, the following vulnerability has been resolved:
l2tp: use refcount_inc_not_zero in l2tp_session_get_by_ifname
A reader in l2tp_session_get_by_ifname() can return a pointer to a
session whose refcount has reached zero. The getter takes its
reference with plain refcount_inc(), but every other session getter
in the same file (l2tp_v2_session_get, l2tp_v3_session_get, and the
corresponding _get_next variants) uses refcount_inc_not_zero()
because the IDR/RCU lookup can race with refcount_dec_and_test() ->
l2tp_session_free() -> kfree_rcu(). The ifname getter is the only
outlier; the inconsistency was raised on-list after 979c017803c4
("l2tp: use list_del_rcu in l2tp_session_unhash").
A reader inside rcu_read_lock_bh() that matches session->ifname can
be preempted between the strcmp() and the refcount_inc(). If the
last reference drops on another CPU in that window, the reader's
refcount_inc() runs on a counter that has reached zero. refcount_t
catches the addition-on-zero, prints "refcount_t: addition on 0;
use-after-free", saturates the counter, and returns the saturated
pointer to the caller. Session memory is held live by the in-flight
RCU read section, but the kfree_rcu() callback queued from
l2tp_session_free() will free it once the grace period closes; a
caller that dereferences the returned session past that point hits
a slab-use-after-free. On PREEMPT_RT local_bh_disable() is a per-CPU
sleeping lock and the preemption window is real; on stock PREEMPT
kernels local_bh_disable() is a preempt_count increment that closes
the cross-CPU race in practice (see below).
Use refcount_inc_not_zero() and continue the list walk on failure,
matching the other session getters in the file. The ifname getter
is the only session getter in net/l2tp/ that still uses the bare
refcount_inc() pattern; this change restores file-internal
consistency. The success path is unchanged. |
| In the Linux kernel, the following vulnerability has been resolved:
cifs: Fix busy dentry used after unmounting
Since commit 340cea84f691c ("cifs: open files should not hold ref on
superblock"), cifs file only holds the dentry ref_cnt, the cifs file
close work(cfile->deferred) could be executed after unmounting, which
will trigger a warning in generic_shutdown_super:
BUG: Dentry 00000000a14a6845{i=c,n=file} still in use (1) [unmount of
cifs cifs]
The detailed processs is:
process A process B kworker
fd = open(PATH)
vfs_open
file->__f_path = *path // dentry->d_lockref.count = 1
cifs_open
cifs_new_fileinfo
cfile->dentry = dget(dentry) // dentry->d_lockref.count = 2
close(fd)
__fput
cifs_close
queue_delayed_work(deferredclose_wq, cfile->deferred)
dput(dentry) // dentry->d_lockref.count = 1
smb2_deferred_work_close
_cifsFileInfo_put
list_del(&cifs_file->flist)
umount
cleanup_mnt
deactivate_super
cifs_kill_sb
cifs_close_all_deferred_files_sb
cifs_close_all_deferred_files
// cannot find cfile, skip _cifsFileInfo_put
kill_anon_super
generic_shutdown_super
shrink_dcache_for_umount
umount_check
WARN ! // dentry->d_lockref.count = 1
cifsFileInfo_put_final
dput(cifs_file->dentry)
// dentry->d_lockref.count = 0
Fix it by flushing 'deferredclose_wq' before calling kill_anon_super.
Fetch a reproducer in https://bugzilla.kernel.org/show_bug.cgi?id=221548. |
| In the Linux kernel, the following vulnerability has been resolved:
mm/memory_hotplug: fix memory block reference leak on remove
Patch series "mm: Fix memory block leaks and locking", v2.
This series fixes two memory block device reference leaks and one locking
issue around the per-memory_block hwpoison counter.
This patch (of 2):
remove_memory_blocks_and_altmaps() looks up each memory block with
find_memory_block(), which acquires a reference to the memory block
device.
That reference is never dropped on this path, resulting in a leaked device
reference when removing memory blocks and their altmaps. Drop the
reference after retrieving mem->altmap and clearing mem->altmap, before
removing the memory block device. |
| In the Linux kernel, the following vulnerability has been resolved:
drm/msm/adreno: Fix a reference leak in a6xx_gpu_init()
In a6xx_gpu_init(), node is obtained via of_parse_phandle().
While there was a manual of_node_put() at the end of the
common path, several early error returns would bypass this call,
resulting in a reference leak.
Fix this by using the __free(device_node) cleanup handler to
release the reference when the variable goes out of scope.
Patchwork: https://patchwork.freedesktop.org/patch/700661/ |
| In the Linux kernel, the following vulnerability has been resolved:
batman-adv: tp_meter: fix tp_vars reference leak in receiver shutdown
The receiver shutdown timer handler, batadv_tp_receiver_shutdown(), is
responsible for releasing the tp_vars reference it holds. However, the
existing logic for coordinating this release with batadv_tp_stop_all() was
flawed.
timer_shutdown_sync() guarantees the timer will not fire again after it
returns, but it returns non-zero only when the timer was pending at the
time of the call. If the timer had already expired (and
batadv_tp_stop_all() would unsucessfully try to rearm itself),
batadv_tp_stop_all() skips its batadv_tp_vars_put(), and
batadv_tp_receiver_shutdown() fails to put its own reference as well.
Fix this by introducing a new atomic variable receiving that is set to 1
when the receiver is initialized and cleared atomically with atomic_xchg()
by whichever side claims it first. Only the side that observes the
transition from 1 to 0 is responsible for releasing the tp_vars timer
reference, eliminating the uncertainty. |
| In the Linux kernel, the following vulnerability has been resolved:
drm/colorop: Fix blob property reference tracking in state lifecycle
The colorop state blob property handling had memory leaks during state
duplication, destruction, and reset operations. The implementation
failed to follow the established pattern from drm_crtc's handling of
DEGAMMA/GAMMA blob properties.
Issues fixed:
- drm_colorop_atomic_destroy_state() was freeing state memory without
releasing the blob reference, causing a leak
- drm_colorop_reset() was directly freeing old state with kfree()
instead of properly destroying it, leaking blob references
- drm_colorop_cleanup() had duplicate blob cleanup code
Changes:
- Add __drm_atomic_helper_colorop_destroy_state() helper to properly
release blob references before freeing state memory
- Update drm_colorop_atomic_destroy_state() to call the helper
- Fix drm_colorop_reset() to use drm_colorop_atomic_destroy_state()
for proper cleanup of old state
- Simplify drm_colorop_cleanup() to use the common destruction path
This matches the well-tested pattern used by drm_crtc since 2016 and
ensures proper reference counting throughout the state lifecycle.
Co-developed by Claude Sonnet 4.5. |
| In the Linux kernel, the following vulnerability has been resolved:
vsock/virtio: fix zerocopy completion for multi-skb sends
When a large message is fragmented into multiple skbs, the zerocopy
uarg is only allocated and attached to the last skb in the loop.
Non-final skbs carry pinned user pages with no completion tracking,
so the kernel has no way to notify userspace when those pages are safe
to reuse. If the loop breaks early the uarg is never allocated at all,
leaking pinned pages with no completion notification.
Fix this by following the approach used by TCP: allocate the zerocopy
uarg (if not provided by the caller) before the send loop and attach
it to every skb via skb_zcopy_set(), which takes a reference per skb.
Each skb's completion properly decrements the refcount, and the
notification only fires after the last skb is freed.
On failure, if no data was sent, the uarg is cleanly aborted via
net_zcopy_put_abort().
This issue was initially discovered by sashiko while reviewing commit
1cb36e252211 ("vsock/virtio: fix MSG_ZEROCOPY pinned-pages accounting")
but was pre-existing. |
| In the Linux kernel, the following vulnerability has been resolved:
iio: light: bh1780: fix PM runtime leak on error path
Move pm_runtime_put_autosuspend() before the error check to ensure
the PM runtime reference count is always decremented after
pm_runtime_get_sync(), regardless of whether the read operation
succeeds or fails. |
| In the Linux kernel, the following vulnerability has been resolved:
gpio: Fix resource leaks on errors in gpiochip_add_data_with_key()
Since commit aab5c6f20023 ("gpio: set device type for GPIO chips"),
`gdev->dev.release` is unset. As a result, the reference count to
`gdev->dev` isn't dropped on the error handling paths.
Drop the reference on errors.
Also reorder the instructions to make the error handling simpler.
Now gpiochip_add_data_with_key() roughly looks like:
>>> Some memory allocation. Go to ERR ZONE 1 on errors.
>>> device_initialize().
gpiodev_release() takes over the responsibility for freeing the
resources of `gdev->dev`. The subsequent error handling paths
shouldn't go through ERR ZONE 1 again which leads to double free.
>>> Some initialization mainly on `gdev`.
>>> The rest of initialization. Go to ERR ZONE 2 on errors.
>>> Chip registration success and exit.
>>> ERR ZONE 2. gpio_device_put() and exit.
>>> ERR ZONE 1. |
| A flaw was found in grub2. When failing to mount an HFS+ grub, the hfsplus filesystem driver doesn't properly set an ERRNO value. This issue may lead to a NULL pointer access. |
| In the Linux kernel, the following vulnerability has been resolved:
ksmbd: fix use-after-free in smb2_open during durable reconnect
In smb2_open, the call to ksmbd_put_durable_fd(fp) drops the reference
to the durable file descriptor early during the durable reconnect
process. If an error occurs subsequently (eg, ksmbd_iov_pin_rsp fails)
or a scavenger accesses the file, it leads to a use-after-free when
accessing fp properties (eg fp->create_time).
Move the single put to the end of the function below err_out2 so fp
stays valid until smb2_open returns. |
| In the Linux kernel, the following vulnerability has been resolved:
l2tp: pppol2tp: hold reference to session in pppol2tp_ioctl()
pppol2tp_ioctl() read sock->sk->sk_user_data directly without any
locks or reference counting. If a controllable sleep was induced during
copy_from_user() (e.g. via a userfaultfd page fault sleep), a concurrent
socket close could trigger pppol2tp_session_close() asynchronously. This
frees the l2tp_session structure via the l2tp_session_del_work workqueue.
Upon resuming, the ioctl thread dereferences the stale session pointer,
resulting in a Use-After-Free (UAF).
Fix this by securely fetching the session reference using the RCU-safe,
refcounted helper pppol2tp_sock_to_session(sk) on entry. This locks the
session's refcount across the sleep. We structured the function to exit
via standard err breaks, guaranteeing that l2tp_session_put() is cleanly
called on all return paths to drop the reference.
To preserve existing behavior we validate the session and its magic
signature only for the specific L2TP commands that require it. This
ensures that generic/unknown ioctls called on an unconnected socket
still return -ENOIOCTLCMD and correctly fall back to generic handlers
(e.g. in sock_do_ioctl()). |
| In the Linux kernel, the following vulnerability has been resolved:
net: airoha: Fix use-after-free in metadata dst teardown
airoha_metadata_dst_free() runs metadata_dst_free() which frees the
metadata_dst with kfree() immediately, bypassing the RCU grace period.
In the RX path, skb_dst_set_noref() sets a non-refcounted pointer from
the skb to the metadata_dst. This function requires RCU read-side
protection and the dst must remain valid until all RCU readers complete.
Since metadata_dst_free() calls kfree() directly, an use-after-free can
occur if any skb still holds a noref pointer to the dst when the driver
tears it down.
Replace metadata_dst_free() with dst_release() which properly goes
through the refcount path: when the refcount drops to zero, it schedules
the actual free via call_rcu_hurry(), ensuring all RCU readers have
completed before the memory is freed. |
| In the Linux kernel, the following vulnerability has been resolved:
NFSD: fix nfs4_file access extra count in nfsd4_add_rdaccess_to_wrdeleg
In nfsd4_add_rdaccess_to_wrdeleg, if fp->fi_fds[O_RDONLY] is already
set by another thread, __nfs4_file_get_access should not be called
to increment the nfs4_file access count since that was already done
by the thread that added READ access to the file. The extra fi_access
count in nfs4_file can prevent the corresponding nfsd_file from being
freed.
When stopping nfs-server service, these extra access counts trigger a
BUG in kmem_cache_destroy() that shows nfsd_file object remaining on
__kmem_cache_shutdown.
This problem can be reproduced by running the Git project's test
suite over NFS. |
