In the Linux kernel, the following vulnerability has been resolved:
media: dvb-frontends: w7090p: fix null-ptr-deref in w7090p_tuner_write_serpar and w7090p_tuner_read_serpar
In w7090p_tuner_write_serpar, msg is controlled by user. When msg[0].buf is null and msg[0].len is zero, former checks on msg[0].buf would be passed. If accessing msg[0].buf[2] without sanity check, null pointer deref would happen. We add
check on msg[0].len to prevent crash.
Similar commit: commit 0ed554fd769a ("media: dvb-usb: az6027: fix null-ptr-deref in az6027_i2c_xfer()")
In the Linux kernel, the following vulnerability has been resolved:
media: dvb-frontends: dib7090p: fix null-ptr-deref in dib7090p_rw_on_apb()
In dib7090p_rw_on_apb, msg is controlled by user. When msg[0].buf is null and
msg[0].len is zero, former checks on msg[0].buf would be passed. If accessing
msg[0].buf[2] without sanity check, null pointer deref would happen. We add
check on msg[0].len to prevent crash. Similar issue occurs when access
msg[1].buf[0] and msg[1].buf[1].
Similar commit: commit 0ed554fd769a ("media: dvb-usb: az6027: fix null-ptr-deref in az6027_i2c_xfer()")
In the Linux kernel, the following vulnerability has been resolved:
scsi: lpfc: Check for hdwq null ptr when cleaning up lpfc_vport structure
If a call to lpfc_sli4_read_rev() from lpfc_sli4_hba_setup() fails, the
resultant cleanup routine lpfc_sli4_vport_delete_fcp_xri_aborted() may
occur before sli4_hba.hdwqs are allocated. This may result in a null
pointer dereference when attempting to take the abts_io_buf_list_lock for
the first hardware queue. Fix by adding a null ptr check on
phba->sli4_hba.hdwq and early return because this situation means there
must have been an error during port initialization.
In the Linux kernel, the following vulnerability has been resolved:
fbdev: Fix vmalloc out-of-bounds write in fast_imageblit
This issue triggers when a userspace program does an ioctl
FBIOPUT_CON2FBMAP by passing console number and frame buffer number.
Ideally this maps console to frame buffer and updates the screen if
console is visible.
As part of mapping it has to do resize of console according to frame
buffer info. if this resize fails and returns from vc_do_resize() and
continues further. At this point console and new frame buffer are mapped
and sets display vars. Despite failure still it continue to proceed
updating the screen at later stages where vc_data is related to previous
frame buffer and frame buffer info and display vars are mapped to new
frame buffer and eventully leading to out-of-bounds write in
fast_imageblit(). This bheviour is excepted only when fg_console is
equal to requested console which is a visible console and updates screen
with invalid struct references in fbcon_putcs().
In the Linux kernel, the following vulnerability has been resolved:
comedi: fix race between polling and detaching
syzbot reports a use-after-free in comedi in the below link, which is
due to comedi gladly removing the allocated async area even though poll
requests are still active on the wait_queue_head inside of it. This can
cause a use-after-free when the poll entries are later triggered or
removed, as the memory for the wait_queue_head has been freed. We need
to check there are no tasks queued on any of the subdevices' wait queues
before allowing the device to be detached by the `COMEDI_DEVCONFIG`
ioctl.
Tasks will read-lock `dev->attach_lock` before adding themselves to the
subdevice wait queue, so fix the problem in the `COMEDI_DEVCONFIG` ioctl
handler by write-locking `dev->attach_lock` before checking that all of
the subdevices are safe to be deleted. This includes testing for any
sleepers on the subdevices' wait queues. It remains locked until the
device has been detached. This requires the `comedi_device_detach()`
function to be refactored slightly, moving the bulk of it into new
function `comedi_device_detach_locked()`.
Note that the refactor of `comedi_device_detach()` results in
`comedi_device_cancel_all()` now being called while `dev->attach_lock`
is write-locked, which wasn't the case previously, but that does not
matter.
Thanks to Jens Axboe for diagnosing the problem and co-developing this
patch.
In the Linux kernel, the following vulnerability has been resolved:
media: venus: Fix OOB read due to missing payload bound check
Currently, The event_seq_changed() handler processes a variable number
of properties sent by the firmware. The number of properties is indicated
by the firmware and used to iterate over the payload. However, the
payload size is not being validated against the actual message length.
This can lead to out-of-bounds memory access if the firmware provides a
property count that exceeds the data available in the payload. Such a
condition can result in kernel crashes or potential information leaks if
memory beyond the buffer is accessed.
Fix this by properly validating the remaining size of the payload before
each property access and updating bounds accordingly as properties are
parsed.
This ensures that property parsing is safely bounded within the received
message buffer and protects against malformed or malicious firmware
behavior.
In the Linux kernel, the following vulnerability has been resolved:
media: uvcvideo: Fix 1-byte out-of-bounds read in uvc_parse_format()
The buffer length check before calling uvc_parse_format() only ensured
that the buffer has at least 3 bytes (buflen > 2), buf the function
accesses buffer[3], requiring at least 4 bytes.
This can lead to an out-of-bounds read if the buffer has exactly 3 bytes.
Fix it by checking that the buffer has at least 4 bytes in
uvc_parse_format().
In the Linux kernel, the following vulnerability has been resolved:
mm/ptdump: take the memory hotplug lock inside ptdump_walk_pgd()
Memory hot remove unmaps and tears down various kernel page table regions
as required. The ptdump code can race with concurrent modifications of
the kernel page tables. When leaf entries are modified concurrently, the
dump code may log stale or inconsistent information for a VA range, but
this is otherwise not harmful.
But when intermediate levels of kernel page table are freed, the dump code
will continue to use memory that has been freed and potentially
reallocated for another purpose. In such cases, the ptdump code may
dereference bogus addresses, leading to a number of potential problems.
To avoid the above mentioned race condition, platforms such as arm64,
riscv and s390 take memory hotplug lock, while dumping kernel page table
via the sysfs interface /sys/kernel/debug/kernel_page_tables.
Similar race condition exists while checking for pages that might have
been marked W+X via /sys/kernel/debug/kernel_page_tables/check_wx_pages
which in turn calls ptdump_check_wx(). Instead of solving this race
condition again, let's just move the memory hotplug lock inside generic
ptdump_check_wx() which will benefit both the scenarios.
Drop get_online_mems() and put_online_mems() combination from all existing
platform ptdump code paths.
In the Linux kernel, the following vulnerability has been resolved:
netfilter: nf_tables: reject duplicate device on updates
A chain/flowtable update with duplicated devices in the same batch is
possible. Unfortunately, netdev event path only removes the first
device that is found, leaving unregistered the hook of the duplicated
device.
Check if a duplicated device exists in the transaction batch, bail out
with EEXIST in such case.
WARNING is hit when unregistering the hook:
[49042.221275] WARNING: CPU: 4 PID: 8425 at net/netfilter/core.c:340 nf_hook_entry_head+0xaa/0x150
[49042.221375] CPU: 4 UID: 0 PID: 8425 Comm: nft Tainted: G S 6.16.0+ #170 PREEMPT(full)
[...]
[49042.221382] RIP: 0010:nf_hook_entry_head+0xaa/0x150