Linux: >> Linux Kernel >> 5.16.17 Security Vulnerabilities
In the Linux kernel, the following vulnerability has been resolved:
ring-buffer: Fix deadloop issue on reading trace_pipe
Soft lockup occurs when reading file 'trace_pipe':
watchdog: BUG: soft lockup - CPU#6 stuck for 22s! [cat:4488]
[...]
RIP: 0010:ring_buffer_empty_cpu+0xed/0x170
RSP: 0018:ffff88810dd6fc48 EFLAGS: 00000246
RAX: 0000000000000000 RBX: 0000000000000246 RCX: ffffffff93d1aaeb
RDX: ffff88810a280040 RSI: 0000000000000008 RDI: ffff88811164b218
RBP: ffff88811164b218 R08: 0000000000000000 R09: ffff88815156600f
R10: ffffed102a2acc01 R11: 0000000000000001 R12: 0000000051651901
R13: 0000000000000000 R14: ffff888115e49500 R15: 0000000000000000
[...]
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f8d853c2000 CR3: 000000010dcd8000 CR4: 00000000000006e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
__find_next_entry+0x1a8/0x4b0
? peek_next_entry+0x250/0x250
? down_write+0xa5/0x120
? down_write_killable+0x130/0x130
trace_find_next_entry_inc+0x3b/0x1d0
tracing_read_pipe+0x423/0xae0
? tracing_splice_read_pipe+0xcb0/0xcb0
vfs_read+0x16b/0x490
ksys_read+0x105/0x210
? __ia32_sys_pwrite64+0x200/0x200
? switch_fpu_return+0x108/0x220
do_syscall_64+0x33/0x40
entry_SYSCALL_64_after_hwframe+0x61/0xc6
Through the vmcore, I found it's because in tracing_read_pipe(),
ring_buffer_empty_cpu() found some buffer is not empty but then it
cannot read anything due to "rb_num_of_entries() == 0" always true,
Then it infinitely loop the procedure due to user buffer not been
filled, see following code path:
tracing_read_pipe() {
... ...
waitagain:
tracing_wait_pipe() // 1. find non-empty buffer here
trace_find_next_entry_inc() // 2. loop here try to find an entry
__find_next_entry()
ring_buffer_empty_cpu(); // 3. find non-empty buffer
peek_next_entry() // 4. but peek always return NULL
ring_buffer_peek()
rb_buffer_peek()
rb_get_reader_page()
// 5. because rb_num_of_entries() == 0 always true here
// then return NULL
// 6. user buffer not been filled so goto 'waitgain'
// and eventually leads to an deadloop in kernel!!!
}
By some analyzing, I found that when resetting ringbuffer, the 'entries'
of its pages are not all cleared (see rb_reset_cpu()). Then when reducing
the ringbuffer, and if some reduced pages exist dirty 'entries' data, they
will be added into 'cpu_buffer->overrun' (see rb_remove_pages()), which
cause wrong 'overrun' count and eventually cause the deadloop issue.
To fix it, we need to clear every pages in rb_reset_cpu().
CVSS Score
7.1
EPSS Score
0.0
Published
2025-10-07
In the Linux kernel, the following vulnerability has been resolved:
rcu: Avoid stack overflow due to __rcu_irq_enter_check_tick() being kprobe-ed
Registering a kprobe on __rcu_irq_enter_check_tick() can cause kernel
stack overflow as shown below. This issue can be reproduced by enabling
CONFIG_NO_HZ_FULL and booting the kernel with argument "nohz_full=",
and then giving the following commands at the shell prompt:
# cd /sys/kernel/tracing/
# echo 'p:mp1 __rcu_irq_enter_check_tick' >> kprobe_events
# echo 1 > events/kprobes/enable
This commit therefore adds __rcu_irq_enter_check_tick() to the kprobes
blacklist using NOKPROBE_SYMBOL().
Insufficient stack space to handle exception!
ESR: 0x00000000f2000004 -- BRK (AArch64)
FAR: 0x0000ffffccf3e510
Task stack: [0xffff80000ad30000..0xffff80000ad38000]
IRQ stack: [0xffff800008050000..0xffff800008058000]
Overflow stack: [0xffff089c36f9f310..0xffff089c36fa0310]
CPU: 5 PID: 190 Comm: bash Not tainted 6.2.0-rc2-00320-g1f5abbd77e2c #19
Hardware name: linux,dummy-virt (DT)
pstate: 400003c5 (nZcv DAIF -PAN -UAO -TCO -DIT -SSBS BTYPE=--)
pc : __rcu_irq_enter_check_tick+0x0/0x1b8
lr : ct_nmi_enter+0x11c/0x138
sp : ffff80000ad30080
x29: ffff80000ad30080 x28: ffff089c82e20000 x27: 0000000000000000
x26: 0000000000000000 x25: ffff089c02a8d100 x24: 0000000000000000
x23: 00000000400003c5 x22: 0000ffffccf3e510 x21: ffff089c36fae148
x20: ffff80000ad30120 x19: ffffa8da8fcce148 x18: 0000000000000000
x17: 0000000000000000 x16: 0000000000000000 x15: ffffa8da8e44ea6c
x14: ffffa8da8e44e968 x13: ffffa8da8e03136c x12: 1fffe113804d6809
x11: ffff6113804d6809 x10: 0000000000000a60 x9 : dfff800000000000
x8 : ffff089c026b404f x7 : 00009eec7fb297f7 x6 : 0000000000000001
x5 : ffff80000ad30120 x4 : dfff800000000000 x3 : ffffa8da8e3016f4
x2 : 0000000000000003 x1 : 0000000000000000 x0 : 0000000000000000
Kernel panic - not syncing: kernel stack overflow
CPU: 5 PID: 190 Comm: bash Not tainted 6.2.0-rc2-00320-g1f5abbd77e2c #19
Hardware name: linux,dummy-virt (DT)
Call trace:
dump_backtrace+0xf8/0x108
show_stack+0x20/0x30
dump_stack_lvl+0x68/0x84
dump_stack+0x1c/0x38
panic+0x214/0x404
add_taint+0x0/0xf8
panic_bad_stack+0x144/0x160
handle_bad_stack+0x38/0x58
__bad_stack+0x78/0x7c
__rcu_irq_enter_check_tick+0x0/0x1b8
arm64_enter_el1_dbg.isra.0+0x14/0x20
el1_dbg+0x2c/0x90
el1h_64_sync_handler+0xcc/0xe8
el1h_64_sync+0x64/0x68
__rcu_irq_enter_check_tick+0x0/0x1b8
arm64_enter_el1_dbg.isra.0+0x14/0x20
el1_dbg+0x2c/0x90
el1h_64_sync_handler+0xcc/0xe8
el1h_64_sync+0x64/0x68
__rcu_irq_enter_check_tick+0x0/0x1b8
arm64_enter_el1_dbg.isra.0+0x14/0x20
el1_dbg+0x2c/0x90
el1h_64_sync_handler+0xcc/0xe8
el1h_64_sync+0x64/0x68
__rcu_irq_enter_check_tick+0x0/0x1b8
[...]
el1_dbg+0x2c/0x90
el1h_64_sync_handler+0xcc/0xe8
el1h_64_sync+0x64/0x68
__rcu_irq_enter_check_tick+0x0/0x1b8
arm64_enter_el1_dbg.isra.0+0x14/0x20
el1_dbg+0x2c/0x90
el1h_64_sync_handler+0xcc/0xe8
el1h_64_sync+0x64/0x68
__rcu_irq_enter_check_tick+0x0/0x1b8
arm64_enter_el1_dbg.isra.0+0x14/0x20
el1_dbg+0x2c/0x90
el1h_64_sync_handler+0xcc/0xe8
el1h_64_sync+0x64/0x68
__rcu_irq_enter_check_tick+0x0/0x1b8
el1_interrupt+0x28/0x60
el1h_64_irq_handler+0x18/0x28
el1h_64_irq+0x64/0x68
__ftrace_set_clr_event_nolock+0x98/0x198
__ftrace_set_clr_event+0x58/0x80
system_enable_write+0x144/0x178
vfs_write+0x174/0x738
ksys_write+0xd0/0x188
__arm64_sys_write+0x4c/0x60
invoke_syscall+0x64/0x180
el0_svc_common.constprop.0+0x84/0x160
do_el0_svc+0x48/0xe8
el0_svc+0x34/0xd0
el0t_64_sync_handler+0xb8/0xc0
el0t_64_sync+0x190/0x194
SMP: stopping secondary CPUs
Kernel Offset: 0x28da86000000 from 0xffff800008000000
PHYS_OFFSET: 0xfffff76600000000
CPU features: 0x00000,01a00100,0000421b
Memory Limit: none
CVSS Score
5.5
EPSS Score
0.0
Published
2025-10-07
In the Linux kernel, the following vulnerability has been resolved:
ice: Don't tx before switchdev is fully configured
There is possibility that ice_eswitch_port_start_xmit might be
called while some resources are still not allocated which might
cause NULL pointer dereference. Fix this by checking if switchdev
configuration was finished.
CVSS Score
5.5
EPSS Score
0.0
Published
2025-10-07
In the Linux kernel, the following vulnerability has been resolved:
spi: bcm-qspi: return error if neither hif_mspi nor mspi is available
If neither a "hif_mspi" nor "mspi" resource is present, the driver will
just early exit in probe but still return success. Apart from not doing
anything meaningful, this would then also lead to a null pointer access
on removal, as platform_get_drvdata() would return NULL, which it would
then try to dereference when trying to unregister the spi master.
Fix this by unconditionally calling devm_ioremap_resource(), as it can
handle a NULL res and will then return a viable ERR_PTR() if we get one.
The "return 0;" was previously a "goto qspi_resource_err;" where then
ret was returned, but since ret was still initialized to 0 at this place
this was a valid conversion in 63c5395bb7a9 ("spi: bcm-qspi: Fix
use-after-free on unbind"). The issue was not introduced by this commit,
only made more obvious.
CVSS Score
5.5
EPSS Score
0.0
Published
2025-10-07
In the Linux kernel, the following vulnerability has been resolved:
iavf: Fix out-of-bounds when setting channels on remove
If we set channels greater during iavf_remove(), and waiting reset done
would be timeout, then returned with error but changed num_active_queues
directly, that will lead to OOB like the following logs. Because the
num_active_queues is greater than tx/rx_rings[] allocated actually.
Reproducer:
[root@host ~]# cat repro.sh
#!/bin/bash
pf_dbsf="0000:41:00.0"
vf0_dbsf="0000:41:02.0"
g_pids=()
function do_set_numvf()
{
echo 2 >/sys/bus/pci/devices/${pf_dbsf}/sriov_numvfs
sleep $((RANDOM%3+1))
echo 0 >/sys/bus/pci/devices/${pf_dbsf}/sriov_numvfs
sleep $((RANDOM%3+1))
}
function do_set_channel()
{
local nic=$(ls -1 --indicator-style=none /sys/bus/pci/devices/${vf0_dbsf}/net/)
[ -z "$nic" ] && { sleep $((RANDOM%3)) ; return 1; }
ifconfig $nic 192.168.18.5 netmask 255.255.255.0
ifconfig $nic up
ethtool -L $nic combined 1
ethtool -L $nic combined 4
sleep $((RANDOM%3))
}
function on_exit()
{
local pid
for pid in "${g_pids[@]}"; do
kill -0 "$pid" &>/dev/null && kill "$pid" &>/dev/null
done
g_pids=()
}
trap "on_exit; exit" EXIT
while :; do do_set_numvf ; done &
g_pids+=($!)
while :; do do_set_channel ; done &
g_pids+=($!)
wait
Result:
[ 3506.152887] iavf 0000:41:02.0: Removing device
[ 3510.400799] ==================================================================
[ 3510.400820] BUG: KASAN: slab-out-of-bounds in iavf_free_all_tx_resources+0x156/0x160 [iavf]
[ 3510.400823] Read of size 8 at addr ffff88b6f9311008 by task repro.sh/55536
[ 3510.400823]
[ 3510.400830] CPU: 101 PID: 55536 Comm: repro.sh Kdump: loaded Tainted: G O --------- -t - 4.18.0 #1
[ 3510.400832] Hardware name: Powerleader PR2008AL/H12DSi-N6, BIOS 2.0 04/09/2021
[ 3510.400835] Call Trace:
[ 3510.400851] dump_stack+0x71/0xab
[ 3510.400860] print_address_description+0x6b/0x290
[ 3510.400865] ? iavf_free_all_tx_resources+0x156/0x160 [iavf]
[ 3510.400868] kasan_report+0x14a/0x2b0
[ 3510.400873] iavf_free_all_tx_resources+0x156/0x160 [iavf]
[ 3510.400880] iavf_remove+0x2b6/0xc70 [iavf]
[ 3510.400884] ? iavf_free_all_rx_resources+0x160/0x160 [iavf]
[ 3510.400891] ? wait_woken+0x1d0/0x1d0
[ 3510.400895] ? notifier_call_chain+0xc1/0x130
[ 3510.400903] pci_device_remove+0xa8/0x1f0
[ 3510.400910] device_release_driver_internal+0x1c6/0x460
[ 3510.400916] pci_stop_bus_device+0x101/0x150
[ 3510.400919] pci_stop_and_remove_bus_device+0xe/0x20
[ 3510.400924] pci_iov_remove_virtfn+0x187/0x420
[ 3510.400927] ? pci_iov_add_virtfn+0xe10/0xe10
[ 3510.400929] ? pci_get_subsys+0x90/0x90
[ 3510.400932] sriov_disable+0xed/0x3e0
[ 3510.400936] ? bus_find_device+0x12d/0x1a0
[ 3510.400953] i40e_free_vfs+0x754/0x1210 [i40e]
[ 3510.400966] ? i40e_reset_all_vfs+0x880/0x880 [i40e]
[ 3510.400968] ? pci_get_device+0x7c/0x90
[ 3510.400970] ? pci_get_subsys+0x90/0x90
[ 3510.400982] ? pci_vfs_assigned.part.7+0x144/0x210
[ 3510.400987] ? __mutex_lock_slowpath+0x10/0x10
[ 3510.400996] i40e_pci_sriov_configure+0x1fa/0x2e0 [i40e]
[ 3510.401001] sriov_numvfs_store+0x214/0x290
[ 3510.401005] ? sriov_totalvfs_show+0x30/0x30
[ 3510.401007] ? __mutex_lock_slowpath+0x10/0x10
[ 3510.401011] ? __check_object_size+0x15a/0x350
[ 3510.401018] kernfs_fop_write+0x280/0x3f0
[ 3510.401022] vfs_write+0x145/0x440
[ 3510.401025] ksys_write+0xab/0x160
[ 3510.401028] ? __ia32_sys_read+0xb0/0xb0
[ 3510.401031] ? fput_many+0x1a/0x120
[ 3510.401032] ? filp_close+0xf0/0x130
[ 3510.401038] do_syscall_64+0xa0/0x370
[ 3510.401041] ? page_fault+0x8/0x30
[ 3510.401043] entry_SYSCALL_64_after_hwframe+0x65/0xca
[ 3510.401073] RIP: 0033:0x7f3a9bb842c0
[ 3510.401079] Code: 73 01 c3 48 8b 0d d8 cb 2c 00 f7 d8 64 89 01 48 83 c8 ff c3 66 0f 1f 44 00 00 83 3d 89 24 2d 00 00 75 10 b8 01 00 00 00 0f 05 <48> 3d
---truncated---
CVSS Score
7.1
EPSS Score
0.0
Published
2025-10-07
In the Linux kernel, the following vulnerability has been resolved:
bpf, cpumap: Handle skb as well when clean up ptr_ring
The following warning was reported when running xdp_redirect_cpu with
both skb-mode and stress-mode enabled:
------------[ cut here ]------------
Incorrect XDP memory type (-2128176192) usage
WARNING: CPU: 7 PID: 1442 at net/core/xdp.c:405
Modules linked in:
CPU: 7 PID: 1442 Comm: kworker/7:0 Tainted: G 6.5.0-rc2+ #1
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996)
Workqueue: events __cpu_map_entry_free
RIP: 0010:__xdp_return+0x1e4/0x4a0
......
Call Trace:
<TASK>
? show_regs+0x65/0x70
? __warn+0xa5/0x240
? __xdp_return+0x1e4/0x4a0
......
xdp_return_frame+0x4d/0x150
__cpu_map_entry_free+0xf9/0x230
process_one_work+0x6b0/0xb80
worker_thread+0x96/0x720
kthread+0x1a5/0x1f0
ret_from_fork+0x3a/0x70
ret_from_fork_asm+0x1b/0x30
</TASK>
The reason for the warning is twofold. One is due to the kthread
cpu_map_kthread_run() is stopped prematurely. Another one is
__cpu_map_ring_cleanup() doesn't handle skb mode and treats skbs in
ptr_ring as XDP frames.
Prematurely-stopped kthread will be fixed by the preceding patch and
ptr_ring will be empty when __cpu_map_ring_cleanup() is called. But
as the comments in __cpu_map_ring_cleanup() said, handling and freeing
skbs in ptr_ring as well to "catch any broken behaviour gracefully".
CVSS Score
5.5
EPSS Score
0.0
Published
2025-10-07
In the Linux kernel, the following vulnerability has been resolved:
bnxt: avoid overflow in bnxt_get_nvram_directory()
The value of an arithmetic expression is subject
of possible overflow due to a failure to cast operands to a larger data
type before performing arithmetic. Used macro for multiplication instead
operator for avoiding overflow.
Found by Security Code and Linux Verification
Center (linuxtesting.org) with SVACE.
CVSS Score
5.5
EPSS Score
0.0
Published
2025-10-07
In the Linux kernel, the following vulnerability has been resolved:
ext4: fix memory leaks in ext4_fname_{setup_filename,prepare_lookup}
If the filename casefolding fails, we'll be leaking memory from the
fscrypt_name struct, namely from the 'crypto_buf.name' member.
Make sure we free it in the error path on both ext4_fname_setup_filename()
and ext4_fname_prepare_lookup() functions.
CVSS Score
5.5
EPSS Score
0.0
Published
2025-10-07
In the Linux kernel, the following vulnerability has been resolved:
Drivers: hv: vmbus: Don't dereference ACPI root object handle
Since the commit referenced in the Fixes: tag below the VMBus client driver
is walking the ACPI namespace up from the VMBus ACPI device to the ACPI
namespace root object trying to find Hyper-V MMIO ranges.
However, if it is not able to find them it ends trying to walk resources of
the ACPI namespace root object itself.
This object has all-ones handle, which causes a NULL pointer dereference
in the ACPI code (from dereferencing this pointer with an offset).
This in turn causes an oops on boot with VMBus host implementations that do
not provide Hyper-V MMIO ranges in their VMBus ACPI device or its
ancestors.
The QEMU VMBus implementation is an example of such implementation.
I guess providing these ranges is optional, since all tested Windows
versions seem to be able to use VMBus devices without them.
Fix this by explicitly terminating the lookup at the ACPI namespace root
object.
Note that Linux guests under KVM/QEMU do not use the Hyper-V PV interface
by default - they only do so if the KVM PV interface is missing or
disabled.
Example stack trace of such oops:
[ 3.710827] ? __die+0x1f/0x60
[ 3.715030] ? page_fault_oops+0x159/0x460
[ 3.716008] ? exc_page_fault+0x73/0x170
[ 3.716959] ? asm_exc_page_fault+0x22/0x30
[ 3.717957] ? acpi_ns_lookup+0x7a/0x4b0
[ 3.718898] ? acpi_ns_internalize_name+0x79/0xc0
[ 3.720018] acpi_ns_get_node_unlocked+0xb5/0xe0
[ 3.721120] ? acpi_ns_check_object_type+0xfe/0x200
[ 3.722285] ? acpi_rs_convert_aml_to_resource+0x37/0x6e0
[ 3.723559] ? down_timeout+0x3a/0x60
[ 3.724455] ? acpi_ns_get_node+0x3a/0x60
[ 3.725412] acpi_ns_get_node+0x3a/0x60
[ 3.726335] acpi_ns_evaluate+0x1c3/0x2c0
[ 3.727295] acpi_ut_evaluate_object+0x64/0x1b0
[ 3.728400] acpi_rs_get_method_data+0x2b/0x70
[ 3.729476] ? vmbus_platform_driver_probe+0x1d0/0x1d0 [hv_vmbus]
[ 3.730940] ? vmbus_platform_driver_probe+0x1d0/0x1d0 [hv_vmbus]
[ 3.732411] acpi_walk_resources+0x78/0xd0
[ 3.733398] vmbus_platform_driver_probe+0x9f/0x1d0 [hv_vmbus]
[ 3.734802] platform_probe+0x3d/0x90
[ 3.735684] really_probe+0x19b/0x400
[ 3.736570] ? __device_attach_driver+0x100/0x100
[ 3.737697] __driver_probe_device+0x78/0x160
[ 3.738746] driver_probe_device+0x1f/0x90
[ 3.739743] __driver_attach+0xc2/0x1b0
[ 3.740671] bus_for_each_dev+0x70/0xc0
[ 3.741601] bus_add_driver+0x10e/0x210
[ 3.742527] driver_register+0x55/0xf0
[ 3.744412] ? 0xffffffffc039a000
[ 3.745207] hv_acpi_init+0x3c/0x1000 [hv_vmbus]
CVSS Score
5.5
EPSS Score
0.0
Published
2025-10-07
In the Linux kernel, the following vulnerability has been resolved:
ALSA: ac97: Fix possible NULL dereference in snd_ac97_mixer
smatch error:
sound/pci/ac97/ac97_codec.c:2354 snd_ac97_mixer() error:
we previously assumed 'rac97' could be null (see line 2072)
remove redundant assignment, return error if rac97 is NULL.
CVSS Score
5.5
EPSS Score
0.0
Published
2025-10-07