Linux: >> Linux Kernel >> 3.16.37 Security Vulnerabilities
In the Linux kernel, the following vulnerability has been resolved:
jfs: truncate good inode pages when hard link is 0
The fileset value of the inode copy from the disk by the reproducer is
AGGR_RESERVED_I. When executing evict, its hard link number is 0, so its
inode pages are not truncated. This causes the bugon to be triggered when
executing clear_inode() because nrpages is greater than 0.
CVSS Score
7.8
EPSS Score
0.0
Published
2025-09-11
In the Linux kernel, the following vulnerability has been resolved:
rcu: Fix rcu_read_unlock() deadloop due to IRQ work
During rcu_read_unlock_special(), if this happens during irq_exit(), we
can lockup if an IPI is issued. This is because the IPI itself triggers
the irq_exit() path causing a recursive lock up.
This is precisely what Xiongfeng found when invoking a BPF program on
the trace_tick_stop() tracepoint As shown in the trace below. Fix by
managing the irq_work state correctly.
irq_exit()
__irq_exit_rcu()
/* in_hardirq() returns false after this */
preempt_count_sub(HARDIRQ_OFFSET)
tick_irq_exit()
tick_nohz_irq_exit()
tick_nohz_stop_sched_tick()
trace_tick_stop() /* a bpf prog is hooked on this trace point */
__bpf_trace_tick_stop()
bpf_trace_run2()
rcu_read_unlock_special()
/* will send a IPI to itself */
irq_work_queue_on(&rdp->defer_qs_iw, rdp->cpu);
A simple reproducer can also be obtained by doing the following in
tick_irq_exit(). It will hang on boot without the patch:
static inline void tick_irq_exit(void)
{
+ rcu_read_lock();
+ WRITE_ONCE(current->rcu_read_unlock_special.b.need_qs, true);
+ rcu_read_unlock();
+
[neeraj: Apply Frederic's suggested fix for PREEMPT_RT]
CVSS Score
7.1
EPSS Score
0.0
Published
2025-09-11
In the Linux kernel, the following vulnerability has been resolved:
rcutorture: Fix rcutorture_one_extend_check() splat in RT kernels
For built with CONFIG_PREEMPT_RT=y kernels, running rcutorture
tests resulted in the following splat:
[ 68.797425] rcutorture_one_extend_check during change: Current 0x1 To add 0x1 To remove 0x0 preempt_count() 0x0
[ 68.797533] WARNING: CPU: 2 PID: 512 at kernel/rcu/rcutorture.c:1993 rcutorture_one_extend_check+0x419/0x560 [rcutorture]
[ 68.797601] Call Trace:
[ 68.797602] <TASK>
[ 68.797619] ? lockdep_softirqs_off+0xa5/0x160
[ 68.797631] rcutorture_one_extend+0x18e/0xcc0 [rcutorture 2466dbd2ff34dbaa36049cb323a80c3306ac997c]
[ 68.797646] ? local_clock+0x19/0x40
[ 68.797659] rcu_torture_one_read+0xf0/0x280 [rcutorture 2466dbd2ff34dbaa36049cb323a80c3306ac997c]
[ 68.797678] ? __pfx_rcu_torture_one_read+0x10/0x10 [rcutorture 2466dbd2ff34dbaa36049cb323a80c3306ac997c]
[ 68.797804] ? __pfx_rcu_torture_timer+0x10/0x10 [rcutorture 2466dbd2ff34dbaa36049cb323a80c3306ac997c]
[ 68.797815] rcu-torture: rcu_torture_reader task started
[ 68.797824] rcu-torture: Creating rcu_torture_reader task
[ 68.797824] rcu_torture_reader+0x238/0x580 [rcutorture 2466dbd2ff34dbaa36049cb323a80c3306ac997c]
[ 68.797836] ? kvm_sched_clock_read+0x15/0x30
Disable BH does not change the SOFTIRQ corresponding bits in
preempt_count() for RT kernels, this commit therefore use
softirq_count() to check the if BH is disabled.
CVSS Score
5.5
EPSS Score
0.0
Published
2025-09-11
In the Linux kernel, the following vulnerability has been resolved:
wifi: ath10k: shutdown driver when hardware is unreliable
In rare cases, ath10k may lose connection with the PCIe bus due to
some unknown reasons, which could further lead to system crashes during
resuming due to watchdog timeout:
ath10k_pci 0000:01:00.0: wmi command 20486 timeout, restarting hardware
ath10k_pci 0000:01:00.0: already restarting
ath10k_pci 0000:01:00.0: failed to stop WMI vdev 0: -11
ath10k_pci 0000:01:00.0: failed to stop vdev 0: -11
ieee80211 phy0: PM: **** DPM device timeout ****
Call Trace:
panic+0x125/0x315
dpm_watchdog_set+0x54/0x54
dpm_watchdog_handler+0x57/0x57
call_timer_fn+0x31/0x13c
At this point, all WMI commands will timeout and attempt to restart
device. So set a threshold for consecutive restart failures. If the
threshold is exceeded, consider the hardware is unreliable and all
ath10k operations should be skipped to avoid system crash.
fail_cont_count and pending_recovery are atomic variables, and
do not involve complex conditional logic. Therefore, even if recovery
check and reconfig complete are executed concurrently, the recovery
mechanism will not be broken.
Tested-on: QCA6174 hw3.2 PCI WLAN.RM.4.4.1-00288-QCARMSWPZ-1
CVSS Score
5.5
EPSS Score
0.0
Published
2025-09-11
In the Linux kernel, the following vulnerability has been resolved:
serial: 8250: fix panic due to PSLVERR
When the PSLVERR_RESP_EN parameter is set to 1, the device generates
an error response if an attempt is made to read an empty RBR (Receive
Buffer Register) while the FIFO is enabled.
In serial8250_do_startup(), calling serial_port_out(port, UART_LCR,
UART_LCR_WLEN8) triggers dw8250_check_lcr(), which invokes
dw8250_force_idle() and serial8250_clear_and_reinit_fifos(). The latter
function enables the FIFO via serial_out(p, UART_FCR, p->fcr).
Execution proceeds to the serial_port_in(port, UART_RX).
This satisfies the PSLVERR trigger condition.
When another CPU (e.g., using printk()) is accessing the UART (UART
is busy), the current CPU fails the check (value & ~UART_LCR_SPAR) ==
(lcr & ~UART_LCR_SPAR) in dw8250_check_lcr(), causing it to enter
dw8250_force_idle().
Put serial_port_out(port, UART_LCR, UART_LCR_WLEN8) under the port->lock
to fix this issue.
Panic backtrace:
[ 0.442336] Oops - unknown exception [#1]
[ 0.442343] epc : dw8250_serial_in32+0x1e/0x4a
[ 0.442351] ra : serial8250_do_startup+0x2c8/0x88e
...
[ 0.442416] console_on_rootfs+0x26/0x70
CVSS Score
5.5
EPSS Score
0.0
Published
2025-09-05
In the Linux kernel, the following vulnerability has been resolved:
parisc: Revise __get_user() to probe user read access
Because of the way read access support is implemented, read access
interruptions are only triggered at privilege levels 2 and 3. The
kernel executes at privilege level 0, so __get_user() never triggers
a read access interruption (code 26). Thus, it is currently possible
for user code to access a read protected address via a system call.
Fix this by probing read access rights at privilege level 3 (PRIV_USER)
and setting __gu_err to -EFAULT (-14) if access isn't allowed.
Note the cmpiclr instruction does a 32-bit compare because COND macro
doesn't work inside asm.
CVSS Score
5.5
EPSS Score
0.0
Published
2025-09-05
In the Linux kernel, the following vulnerability has been resolved:
media: usbtv: Lock resolution while streaming
When an program is streaming (ffplay) and another program (qv4l2)
changes the TV standard from NTSC to PAL, the kernel crashes due to trying
to copy to unmapped memory.
Changing from NTSC to PAL increases the resolution in the usbtv struct,
but the video plane buffer isn't adjusted, so it overflows.
[hverkuil: call vb2_is_busy instead of vb2_is_streaming]
CVSS Score
5.5
EPSS Score
0.0
Published
2025-09-05
In the Linux kernel, the following vulnerability has been resolved:
comedi: Fix use of uninitialized memory in do_insn_ioctl() and do_insnlist_ioctl()
syzbot reports a KMSAN kernel-infoleak in `do_insn_ioctl()`. A kernel
buffer is allocated to hold `insn->n` samples (each of which is an
`unsigned int`). For some instruction types, `insn->n` samples are
copied back to user-space, unless an error code is being returned. The
problem is that not all the instruction handlers that need to return
data to userspace fill in the whole `insn->n` samples, so that there is
an information leak. There is a similar syzbot report for
`do_insnlist_ioctl()`, although it does not have a reproducer for it at
the time of writing.
One culprit is `insn_rw_emulate_bits()` which is used as the handler for
`INSN_READ` or `INSN_WRITE` instructions for subdevices that do not have
a specific handler for that instruction, but do have an `INSN_BITS`
handler. For `INSN_READ` it only fills in at most 1 sample, so if
`insn->n` is greater than 1, the remaining `insn->n - 1` samples copied
to userspace will be uninitialized kernel data.
Another culprit is `vm80xx_ai_insn_read()` in the "vm80xx" driver. It
never returns an error, even if it fails to fill the buffer.
Fix it in `do_insn_ioctl()` and `do_insnlist_ioctl()` by making sure
that uninitialized parts of the allocated buffer are zeroed before
handling each instruction.
Thanks to Arnaud Lecomte for their fix to `do_insn_ioctl()`. That fix
replaced the call to `kmalloc_array()` with `kcalloc()`, but it is not
always necessary to clear the whole buffer.
CVSS Score
5.5
EPSS Score
0.0
Published
2025-09-05
In the Linux kernel, the following vulnerability has been resolved:
comedi: pcl726: Prevent invalid irq number
The reproducer passed in an irq number(0x80008000) that was too large,
which triggered the oob.
Added an interrupt number check to prevent users from passing in an irq
number that was too large.
If `it->options[1]` is 31, then `1 << it->options[1]` is still invalid
because it shifts a 1-bit into the sign bit (which is UB in C).
Possible solutions include reducing the upper bound on the
`it->options[1]` value to 30 or lower, or using `1U << it->options[1]`.
The old code would just not attempt to request the IRQ if the
`options[1]` value were invalid. And it would still configure the
device without interrupts even if the call to `request_irq` returned an
error. So it would be better to combine this test with the test below.
CVSS Score
7.1
EPSS Score
0.0
Published
2025-09-05
In the Linux kernel, the following vulnerability has been resolved:
comedi: Make insn_rw_emulate_bits() do insn->n samples
The `insn_rw_emulate_bits()` function is used as a default handler for
`INSN_READ` instructions for subdevices that have a handler for
`INSN_BITS` but not for `INSN_READ`. Similarly, it is used as a default
handler for `INSN_WRITE` instructions for subdevices that have a handler
for `INSN_BITS` but not for `INSN_WRITE`. It works by emulating the
`INSN_READ` or `INSN_WRITE` instruction handling with a constructed
`INSN_BITS` instruction. However, `INSN_READ` and `INSN_WRITE`
instructions are supposed to be able read or write multiple samples,
indicated by the `insn->n` value, but `insn_rw_emulate_bits()` currently
only handles a single sample. For `INSN_READ`, the comedi core will
copy `insn->n` samples back to user-space. (That triggered KASAN
kernel-infoleak errors when `insn->n` was greater than 1, but that is
being fixed more generally elsewhere in the comedi core.)
Make `insn_rw_emulate_bits()` either handle `insn->n` samples, or return
an error, to conform to the general expectation for `INSN_READ` and
`INSN_WRITE` handlers.
CVSS Score
7.8
EPSS Score
0.0
Published
2025-09-05