virtio-net: Ensure that TCP packets don't overflow gso_segs
In the Linux kernel, the following vulnerability has been resolved:
virtio-net: Ensure that TCP packets don't overflow gso_segs
The user can specify any gso_size in a packet crafted with an AF_PACKET
PACKET_VNET_HDR socket, even smaller than TCP_MIN_GSO_SIZE = 8. At the
same time, GSO_MAX_SIZE = 8 * GSO_MAX_SEGS = 8 * 65535. When the user
crafts a packet with gso_size < 8, there is a risk for partial GSO to
overflow the 16-bit gso_segs field when dividing the SKB length by
gso_size.
Adjust gso_size of TCP packets to be at least TCP_MIN_GSO_SIZE = 8. Keep
gso_size of UDP GSO packets, as gso_size=1 is valid and explicitly
tested at tools/tes
net/sched: bound qdisc_pkt_len to prevent qdisc soft lockup
In the Linux kernel, the following vulnerability has been resolved:
net/sched: bound qdisc_pkt_len to prevent qdisc soft lockup
qdisc_get_stab() accepts a user-supplied size table, and
__qdisc_calculate_pkt_len() amplifies qdisc_pkt_len() through the
overhead, the size-table data (u16), and size_log (up to
STAB_SIZE_LOG_MAX). A crafted stab can therefore set qdisc_pkt_len()
to ~1 GiB for an ordinary skb. Per-flow deficit schedulers such as
DRR and ETS replenish one quantum per loop iteration; with a tiny
quantum (1) they spin billions of times under the qdisc lock,
producing a soft lockup / RCU stall as illustrated by [email protected].
Cap
slip: remove slip_hangup() to fix use-after-free in slip_receive_buf()
In the Linux kernel, the following vulnerability has been resolved:
slip: remove slip_hangup() to fix use-after-free in slip_receive_buf()
Jaeyoung Chung and Eulgyu Kim reported a slab-use-after-free read
in slip_receive_buf() when racing against tty hangup.
tty_ldisc_hangup() calls ld->ops->hangup() while holding only
a read lock on tty->ldisc_sem (via tty_ldisc_ref()).
Because slip_hangup() simply called slip_close(), it ran concurrently
with reader functions such as slip_receive_buf().
slip_close() unregisters and frees the net device and its private
struct slip, causing concurrent reader threads in slip_receive_buf()
to dereference fr
In the Linux kernel, the following vulnerability has been resolved:
net: fec: only stop PTP if it was initialized
fec_ptp_init() is only called when fep->bufdesc_ex is available.
However, fec_probe() unconditionally calls fec_ptp_stop() on the
failed_init path, and fec_drv_remove() unconditionally calls
fec_ptp_stop() during device removal.
Check fep->bufdesc_ex before calling fec_ptp_stop() in both paths
to avoid stopping PTP when it was not initialized.
In the Linux kernel, the following vulnerability has been resolved:
usb: atm: usbatm: fix invalid ci_range initialization
syzbot reported a shift-out-of-bounds in __vcc_connect():
UBSAN: shift-out-of-bounds in net/atm/common.c:382:32
shift exponent -1 is negative
CPU: 0 UID: 0 PID: 5987 Comm: syz.0.18 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Compute Engine/Google Compute Engine, BIOS Google 08/05/2026
Call Trace:
<TASK>
dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
ubsan_epilogue+0xa/0x30 lib/ubsan.c:233
__ubsan_handle_shift_out_of_bounds+0x36d/0x400 lib/ubsan.c:494
__vcc_connect+0x14b4/0x19c0
tcp: fix corruption of urgent data on multi-segment retransmit
In the Linux kernel, the following vulnerability has been resolved:
tcp: fix corruption of urgent data on multi-segment retransmit
On the normal xmit path, while in urgent mode we refuse to build a
multi-segment TSO packet, so every segment gets its own urg_ptr:
/* tcp_write_xmit() */
limit = mss_now;
if (tso_segs > 1 && !tcp_urg_mode(tp))
limit = tcp_mss_split_point(...);
The retransmit path has no such guard. __tcp_retransmit_skb() builds a
segs > 1 skb and hands it to the GSO layer, which only advances th->seq
per segment and copies urg_ptr verbatim:
/* __tcp_retransmit_skb() */
len = cur_mss * segs; /* segs > 1, no urg_mode c
In the Linux kernel, the following vulnerability has been resolved:
net/sched: sch_htb: limit htb_classify inner-class filter hops
htb_classify() follows each filter-selected inner class by switching
to cl->filter_list, but never bounds the number of hops. A filter on
an inner class can point back to itself or to another inner class that
points back, creating an infinite loop in the packet classification
path with the qdisc lock held and BH disabled — a soft lockup / panic
from a single packet.
Bound the traversal with a hop counter and drop the packet with a
rate-limited warning once the bound is exceeded. The counter is
incremented at th
net: skbuff: don't skb_tx_error() the source skb in skb_zerocopy()
In the Linux kernel, the following vulnerability has been resolved:
net: skbuff: don't skb_tx_error() the source skb in skb_zerocopy()
skb_zerocopy() copies frags from @from into @to. On an
skb_orphan_frags() failure it calls skb_tx_error(@from), a destructive
operation on the source skb the copy helper does not own. That completes
@from's zerocopy uarg and clears SKBFL_ALL_ZEROCOPY, including the
SKBFL_SHARED_FRAG page-ownership marker.
Both callers already report the failure on their own drop path.
nfnetlink_queue does it at nla_put_failure, and Open vSwitch does it in
the flow-miss drop arm of ovs_dp_process_packet(), so nothing is lost
In the Linux kernel, the following vulnerability has been resolved:
USB: gadget: ffs: fix mm lifetime handling
io_data stores a pointer to the submitting task's mm_struct,
but does not currently hold a reference to it while async
requests are pending.
This can result in a use-after-free if the task exits before
completion handling finishes.
Take a reference with mmgrab() when queuing the read request
and release it with mmdrop() on request completion.
usb: gadget: f_fs: Fix Use-After-Free in AIO error path
In the Linux kernel, the following vulnerability has been resolved:
usb: gadget: f_fs: Fix Use-After-Free in AIO error path
In ffs_epfile_write_iter() and ffs_epfile_read_iter(), when ffs_epfile_io()
fails with an error other than -EIOCBQUEUED, the io_data structure (`p`) is
freed. However, for AIO operations, the kiocb cancel function was already
armed and kiocb->private was set to `p`.
If a concurrent cancel operation (such as sys_io_cancel()) executes after
ffs_epfile_io() fails but before the function frees `p`, a Use-After-Free
can occur when the cancellation handler accesses the freed pointer.
To securely fix this race condition, we
In the Linux kernel, the following vulnerability has been resolved:
HID: sony: clean up device list on probe failure
sony_input_configured() adds some controllers to sony_device_list before
HID core registers their input devices. input_register_device() can fail
after the callback returns successfully. sony_probe() then observes that
HID_CLAIMED_INPUT is clear and unwinds, but only stops the HID hardware.
The devres-managed sony_sc is freed while its list node remains linked, so
the next matching controller traverses freed memory.
Initialize the list node and device ID to inactive states. Make list
removal idempotent and run the driver-pri
NFSD: Prevent client use-after-free during close_lru reaping
In the Linux kernel, the following vulnerability has been resolved:
NFSD: Prevent client use-after-free during close_lru reaping
An nfs4_openowner left on nn->close_lru after its final CLOSE keeps
its last closed stateid in oo_last_closed_stid, holding only a raw
pointer to its nfs4_client. The laundromat reaps timed-out entries,
drops nn->client_lock, and calls nfs4_put_stid(), which dereferences
the client through cl_lock. Nothing pins the client across that
window, so a concurrent force_expire_client() can free it and
nfs4_put_stid() reads freed memory. __destroy_client() hits the same
race, walking clp->cl_openowners without cl_lock.
P
NFSD: Prevent client use-after-free during blocked-lock reaping
In the Linux kernel, the following vulnerability has been resolved:
NFSD: Prevent client use-after-free during blocked-lock reaping
A bare lock owner -- its only remaining reference a blocked lock on
nn->blocked_locks_lru -- holds a raw pointer to its nfs4_client but
no reference keeping the client alive. When the per-net laundromat
reaps such a lock, freeing the nbl drops the owner reference
held through flc_owner, and the final nfs4_put_stateowner()
takes the client's cl_lock. Because the laundromat detaches the
nbl first, __destroy_client() no longer finds it, so a concurrent
force_expire_client() can free the client before nfs4_put_stat
In the Linux kernel, the following vulnerability has been resolved:
usb: image: mdc800: change kmalloc() to kzalloc()
Change the kmalloc() calls in usb_mdc800_init() for irq_urb_buffer and
download_urb_buffer to kzalloc(), avoiding potential stack leaks if a
shorter message is received in mdc800_usb_irq() and
mdc800_usb_download_notify()
ALSA: usb-audio: fix OOB write in snd_usbmidi_us122l_output()
In the Linux kernel, the following vulnerability has been resolved:
ALSA: usb-audio: fix OOB write in snd_usbmidi_us122l_output()
The snd_usbmidi_us122l_output() picks a count of 2 on anything slower
than high speed and never relates it to ep->max_transfer. The URB
buffer holds exactly max_transfer bytes, so a device declaring a one
byte bulk endpoint takes two bytes from snd_rawmidi_transmit(), and the
memset that pads the rest computes 1 - 2 in int and wraps to SIZE_MAX.
Only 0x800e and 0x800f are pinned to nine bytes. The US-122MKII at
0x0644:0x8021 falls to the default and takes usb_maxpacket(), which the
USB core only clamps downwar
media: usbtv: keep device alive while ALSA card exists
In the Linux kernel, the following vulnerability has been resolved:
media: usbtv: keep device alive while ALSA card exists
The ALSA PCM callbacks store the driver state in pcm->private_data. An
open PCM file can outlive USB disconnect because usbtv_audio_free() uses
snd_card_free_when_closed(). The disconnect path can then drop the V4L2
device reference and free struct usbtv before ALSA releases the substream,
so a later close dereferences freed memory in snd_usbtv_pcm_close().
Take a V4L2 device reference for the ALSA card and drop it from the card
private_free callback. This keeps struct usbtv valid until ALSA has closed
the remaining fi
usb-storage: ene_ub6250: fix race between scan work and probe
In the Linux kernel, the following vulnerability has been resolved:
usb-storage: ene_ub6250: fix race between scan work and probe
ene_ub6250_probe() calls usb_stor_probe2(), which starts the usb-storage
infrastructure and schedules the delayed scan work. The driver then
calls ene_get_card_type(), which sends an ENE command through
ene_send_scsi_cmd() and the usb-storage bulk transfer helpers.
Both the delayed scan work, through usb_stor_Bulk_max_lun(), and
ene_get_card_type() use us->current_urb. The scan work serializes this
access with us->dev_mutex, but the ENE card-type probe does not. If the
scan work runs while ene_get_card_type()
usb: storage: realtek_cr: fix use-after-free on disconnect
In the Linux kernel, the following vulnerability has been resolved:
usb: storage: realtek_cr: fix use-after-free on disconnect
realtek_cr_destructor() calls timer_delete() before the chip containing
the timer is freed. The timer callback may still be running and can
rearm itself, resulting in a use-after-free.
Use timer_shutdown_sync() to wait for the callback and prevent further
rearming. Do this unconditionally because ss_en may be changed after
the timer is armed.
Move timer_setup() into init_realtek_cr() so the timer is initialized
before any failure path can invoke the destructor.
Found by static analysis.
usb: gadget: f_mass_storage: fix null pointer dereference in fsg_common_set_num_buffers()
In the Linux kernel, the following vulnerability has been resolved:
usb: gadget: f_mass_storage: fix null pointer dereference in fsg_common_set_num_buffers()
Previously fsg_num_buffers_validate() was removed as it was not
necessary due to Kconfig setting the limits for n from 2 to 256 with
default as 2. However, setting the page content in such a way that
kstrtou8() reflects n value as either 0 or 1 bypasses these
restrictions leading to a null pointer dereference if n is 0. Fix
this by adding a check for n < 2 and returning -EINVAL if n is
either 0 or 1 consistent with Kconfig logic.
USB: gadget: fix NULL pointer dereference in gadget_dev_ioctl()
In the Linux kernel, the following vulnerability has been resolved:
USB: gadget: fix NULL pointer dereference in gadget_dev_ioctl()
gadget_dev_ioctl() reads dev->gadget before acquiring dev->lock, but
dev->state is checked after acquiring the lock. Therefore a concurrent
bind can change the device state between these operations, which can
leave ioctl with a stale NULL gadget pointer and causing a NULL pointer
dereference at gadget->ops->ioctl.
Read dev->gadget while holding dev->lock so that the gadget pointer
and device state are sampled consistently.