Linux: >> Linux Kernel >> 2.6.33.17 Security Vulnerabilities
In the Linux kernel, the following vulnerability has been resolved:
comedi: Reinit dev->spinlock between attachments to low-level drivers
`struct comedi_device` is the main controlling structure for a COMEDI
device created by the COMEDI subsystem. It contains a member `spinlock`
containing a spin-lock that is initialized by the COMEDI subsystem, but
is reserved for use by a low-level driver attached to the COMEDI device
(at least since commit 25436dc9d84f ("Staging: comedi: remove RT
code")).
Some COMEDI devices (those created on initialization of the COMEDI
subsystem when the "comedi.comedi_num_legacy_minors" parameter is
non-zero) can be attached to different low-level drivers over their
lifetime using the `COMEDI_DEVCONFIG` ioctl command. This can result in
inconsistent lock states being reported when there is a mismatch in the
spin-lock locking levels used by each low-level driver to which the
COMEDI device has been attached. Fix it by reinitializing
`dev->spinlock` before calling the low-level driver's `attach` function
pointer if `CONFIG_LOCKDEP` is enabled.
CVSS Score
5.5
EPSS Score
0.001
Published
2026-05-08
In the Linux kernel, the following vulnerability has been resolved:
ACPI: processor: Fix NULL-pointer dereference in acpi_processor_errata_piix4()
In acpi_processor_errata_piix4(), the pointer dev is first assigned an IDE
device and then reassigned an ISA device:
dev = pci_get_subsys(..., PCI_DEVICE_ID_INTEL_82371AB, ...);
dev = pci_get_subsys(..., PCI_DEVICE_ID_INTEL_82371AB_0, ...);
If the first lookup succeeds but the second fails, dev becomes NULL. This
leads to a potential null-pointer dereference when dev_dbg() is called:
if (errata.piix4.bmisx)
dev_dbg(&dev->dev, ...);
To prevent this, use two temporary pointers and retrieve each device
independently, avoiding overwriting dev with a possible NULL value.
[ rjw: Subject adjustment, added an empty code line ]
CVSS Score
5.5
EPSS Score
0.001
Published
2026-05-08
In the Linux kernel, the following vulnerability has been resolved:
dm: remove fake timeout to avoid leak request
Since commit 15f73f5b3e59 ("blk-mq: move failure injection out of
blk_mq_complete_request"), drivers are responsible for calling
blk_should_fake_timeout() at appropriate code paths and opportunities.
However, the dm driver does not implement its own timeout handler and
relies on the timeout handling of its slave devices.
If an io-timeout-fail error is injected to a dm device, the request
will be leaked and never completed, causing tasks to hang indefinitely.
Reproduce:
1. prepare dm which has iscsi slave device
2. inject io-timeout-fail to dm
echo 1 >/sys/class/block/dm-0/io-timeout-fail
echo 100 >/sys/kernel/debug/fail_io_timeout/probability
echo 10 >/sys/kernel/debug/fail_io_timeout/times
3. read/write dm
4. iscsiadm -m node -u
Result: hang task like below
[ 862.243768] INFO: task kworker/u514:2:151 blocked for more than 122 seconds.
[ 862.244133] Tainted: G E 6.19.0-rc1+ #51
[ 862.244337] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
[ 862.244718] task:kworker/u514:2 state:D stack:0 pid:151 tgid:151 ppid:2 task_flags:0x4288060 flags:0x00080000
[ 862.245024] Workqueue: iscsi_ctrl_3:1 __iscsi_unbind_session [scsi_transport_iscsi]
[ 862.245264] Call Trace:
[ 862.245587] <TASK>
[ 862.245814] __schedule+0x810/0x15c0
[ 862.246557] schedule+0x69/0x180
[ 862.246760] blk_mq_freeze_queue_wait+0xde/0x120
[ 862.247688] elevator_change+0x16d/0x460
[ 862.247893] elevator_set_none+0x87/0xf0
[ 862.248798] blk_unregister_queue+0x12e/0x2a0
[ 862.248995] __del_gendisk+0x231/0x7e0
[ 862.250143] del_gendisk+0x12f/0x1d0
[ 862.250339] sd_remove+0x85/0x130 [sd_mod]
[ 862.250650] device_release_driver_internal+0x36d/0x530
[ 862.250849] bus_remove_device+0x1dd/0x3f0
[ 862.251042] device_del+0x38a/0x930
[ 862.252095] __scsi_remove_device+0x293/0x360
[ 862.252291] scsi_remove_target+0x486/0x760
[ 862.252654] __iscsi_unbind_session+0x18a/0x3e0 [scsi_transport_iscsi]
[ 862.252886] process_one_work+0x633/0xe50
[ 862.253101] worker_thread+0x6df/0xf10
[ 862.253647] kthread+0x36d/0x720
[ 862.254533] ret_from_fork+0x2a6/0x470
[ 862.255852] ret_from_fork_asm+0x1a/0x30
[ 862.256037] </TASK>
Remove the blk_should_fake_timeout() check from dm, as dm has no
native timeout handling and should not attempt to fake timeouts.
CVSS Score
5.5
EPSS Score
0.001
Published
2026-05-08
In the Linux kernel, the following vulnerability has been resolved:
btrfs: don't BUG() on unexpected delayed ref type in run_one_delayed_ref()
There is no need to BUG(), we can just return an error and log an error
message.
CVSS Score
5.5
EPSS Score
0.001
Published
2026-05-08
In the Linux kernel, the following vulnerability has been resolved:
gfs2: fiemap page fault fix
In gfs2_fiemap(), we are calling iomap_fiemap() while holding the inode
glock. This can lead to recursive glock taking if the fiemap buffer is
memory mapped to the same inode and accessing it triggers a page fault.
Fix by disabling page faults for iomap_fiemap() and faulting in the
buffer by hand if necessary.
Fixes xfstest generic/742.
CVSS Score
5.5
EPSS Score
0.001
Published
2026-05-06
In the Linux kernel, the following vulnerability has been resolved:
hfsplus: pretend special inodes as regular files
Since commit af153bb63a33 ("vfs: catch invalid modes in may_open()")
requires any inode be one of S_IFDIR/S_IFLNK/S_IFREG/S_IFCHR/S_IFBLK/
S_IFIFO/S_IFSOCK type, use S_IFREG for special inodes.
CVSS Score
5.5
EPSS Score
0.001
Published
2026-05-06
In the Linux kernel, the following vulnerability has been resolved:
wifi: libertas: fix WARNING in usb_tx_block
The function usb_tx_block() submits cardp->tx_urb without ensuring that
any previous transmission on this URB has completed. If a second call
occurs while the URB is still active (e.g. during rapid firmware loading),
usb_submit_urb() detects the active state and triggers a warning:
'URB submitted while active'.
Fix this by enforcing serialization: call usb_kill_urb() before
submitting the new request. This ensures the URB is idle and safe to reuse.
CVSS Score
5.5
EPSS Score
0.001
Published
2026-05-06
In the Linux kernel, the following vulnerability has been resolved:
alpha: fix user-space corruption during memory compaction
Alpha systems can suffer sporadic user-space crashes and heap
corruption when memory compaction is enabled.
Symptoms include SIGSEGV, glibc allocator failures (e.g. "unaligned
tcache chunk"), and compiler internal errors. The failures disappear
when compaction is disabled or when using global TLB invalidation.
The root cause is insufficient TLB shootdown during page migration.
Alpha relies on ASN-based MM context rollover for instruction cache
coherency, but this alone is not sufficient to prevent stale data or
instruction translations from surviving migration.
Fix this by introducing a migration-specific helper that combines:
- MM context invalidation (ASN rollover),
- immediate per-CPU TLB invalidation (TBI),
- synchronous cross-CPU shootdown when required.
The helper is used only by migration/compaction paths to avoid changing
global TLB semantics.
Additionally, update flush_tlb_other(), pte_clear(), to use
READ_ONCE()/WRITE_ONCE() for correct SMP memory ordering.
This fixes observed crashes on both UP and SMP Alpha systems.
CVSS Score
7.8
EPSS Score
0.001
Published
2026-05-06
In the Linux kernel, the following vulnerability has been resolved:
usb: chipidea: udc: fix DMA and SG cleanup in _ep_nuke()
The ChipIdea UDC driver can encounter "not page aligned sg buffer"
errors when a USB device is reconnected after being disconnected
during an active transfer. This occurs because _ep_nuke() returns
requests to the gadget layer without properly unmapping DMA buffers
or cleaning up scatter-gather bounce buffers.
Root cause:
When a disconnect happens during a multi-segment DMA transfer, the
request's num_mapped_sgs field and sgt.sgl pointer remain set with
stale values. The request is returned to the gadget driver with status
-ESHUTDOWN but still has active DMA state. If the gadget driver reuses
this request on reconnect without reinitializing it, the stale DMA
state causes _hardware_enqueue() to skip DMA mapping (seeing non-zero
num_mapped_sgs) and attempt to use freed/invalid DMA addresses,
leading to alignment errors and potential memory corruption.
The normal completion path via _hardware_dequeue() properly calls
usb_gadget_unmap_request_by_dev() and sglist_do_debounce() before
returning the request. The _ep_nuke() path must do the same cleanup
to ensure requests are returned in a clean, reusable state.
Fix:
Add DMA unmapping and bounce buffer cleanup to _ep_nuke() to mirror
the cleanup sequence in _hardware_dequeue():
- Call usb_gadget_unmap_request_by_dev() if num_mapped_sgs is set
- Call sglist_do_debounce() with copy=false if bounce buffer exists
This ensures that when requests are returned due to endpoint shutdown,
they don't retain stale DMA mappings. The 'false' parameter to
sglist_do_debounce() prevents copying data back (appropriate for
shutdown path where transfer was aborted).
CVSS Score
7.8
EPSS Score
0.001
Published
2026-05-06
In the Linux kernel, the following vulnerability has been resolved:
media: pvrusb2: fix URB leak in pvr2_send_request_ex
When pvr2_send_request_ex() submits a write URB successfully but fails to
submit the read URB (e.g. returns -ENOMEM), it returns immediately without
waiting for the write URB to complete. Since the driver reuses the same
URB structure, a subsequent call to pvr2_send_request_ex() attempts to
submit the still-active write URB, triggering a 'URB submitted while
active' warning in usb_submit_urb().
Fix this by ensuring the write URB is unlinked and waited upon if the read
URB submission fails.
CVSS Score
5.5
EPSS Score
0.001
Published
2026-05-06