In the Linux kernel, the following vulnerability has been resolved:
ALSA: mts64: fix possible null-ptr-defer in snd_mts64_interrupt
I got a null-ptr-defer error report when I do the following tests
on the qemu platform:
make defconfig and CONFIG_PARPORT=m, CONFIG_PARPORT_PC=m,
CONFIG_SND_MTS64=m
Then making test scripts:
cat>test_mod1.sh<<EOF
modprobe snd-mts64
modprobe snd-mts64
EOF
Executing the script, perhaps several times, we will get a null-ptr-defer
report, as follow:
syzkaller:~# ./test_mod.sh
snd_mts64: probe of snd_mts64.0 failed with error -5
modprobe: ERROR: could not insert 'snd_mts64': No such device
BUG: kernel NULL pointer dereference, address: 0000000000000000
#PF: supervisor write access in kernel mode
#PF: error_code(0x0002) - not-present page
PGD 0 P4D 0
Oops: 0002 [#1] PREEMPT SMP PTI
CPU: 0 PID: 205 Comm: modprobe Not tainted 6.1.0-rc8-00588-g76dcd734eca2 #6
Call Trace:
<IRQ>
snd_mts64_interrupt+0x24/0xa0 [snd_mts64]
parport_irq_handler+0x37/0x50 [parport]
__handle_irq_event_percpu+0x39/0x190
handle_irq_event_percpu+0xa/0x30
handle_irq_event+0x2f/0x50
handle_edge_irq+0x99/0x1b0
__common_interrupt+0x5d/0x100
common_interrupt+0xa0/0xc0
</IRQ>
<TASK>
asm_common_interrupt+0x22/0x40
RIP: 0010:_raw_write_unlock_irqrestore+0x11/0x30
parport_claim+0xbd/0x230 [parport]
snd_mts64_probe+0x14a/0x465 [snd_mts64]
platform_probe+0x3f/0xa0
really_probe+0x129/0x2c0
__driver_probe_device+0x6d/0xc0
driver_probe_device+0x1a/0xa0
__device_attach_driver+0x7a/0xb0
bus_for_each_drv+0x62/0xb0
__device_attach+0xe4/0x180
bus_probe_device+0x82/0xa0
device_add+0x550/0x920
platform_device_add+0x106/0x220
snd_mts64_attach+0x2e/0x80 [snd_mts64]
port_check+0x14/0x20 [parport]
bus_for_each_dev+0x6e/0xc0
__parport_register_driver+0x7c/0xb0 [parport]
snd_mts64_module_init+0x31/0x1000 [snd_mts64]
do_one_initcall+0x3c/0x1f0
do_init_module+0x46/0x1c6
load_module+0x1d8d/0x1e10
__do_sys_finit_module+0xa2/0xf0
do_syscall_64+0x37/0x90
entry_SYSCALL_64_after_hwframe+0x63/0xcd
</TASK>
Kernel panic - not syncing: Fatal exception in interrupt
Rebooting in 1 seconds..
The mts wa not initialized during interrupt, we add check for
mts to fix this bug.
Metrics
Affected Vendors & Products
References
History
Wed, 24 Dec 2025 13:15:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| Description | In the Linux kernel, the following vulnerability has been resolved: ALSA: mts64: fix possible null-ptr-defer in snd_mts64_interrupt I got a null-ptr-defer error report when I do the following tests on the qemu platform: make defconfig and CONFIG_PARPORT=m, CONFIG_PARPORT_PC=m, CONFIG_SND_MTS64=m Then making test scripts: cat>test_mod1.sh<<EOF modprobe snd-mts64 modprobe snd-mts64 EOF Executing the script, perhaps several times, we will get a null-ptr-defer report, as follow: syzkaller:~# ./test_mod.sh snd_mts64: probe of snd_mts64.0 failed with error -5 modprobe: ERROR: could not insert 'snd_mts64': No such device BUG: kernel NULL pointer dereference, address: 0000000000000000 #PF: supervisor write access in kernel mode #PF: error_code(0x0002) - not-present page PGD 0 P4D 0 Oops: 0002 [#1] PREEMPT SMP PTI CPU: 0 PID: 205 Comm: modprobe Not tainted 6.1.0-rc8-00588-g76dcd734eca2 #6 Call Trace: <IRQ> snd_mts64_interrupt+0x24/0xa0 [snd_mts64] parport_irq_handler+0x37/0x50 [parport] __handle_irq_event_percpu+0x39/0x190 handle_irq_event_percpu+0xa/0x30 handle_irq_event+0x2f/0x50 handle_edge_irq+0x99/0x1b0 __common_interrupt+0x5d/0x100 common_interrupt+0xa0/0xc0 </IRQ> <TASK> asm_common_interrupt+0x22/0x40 RIP: 0010:_raw_write_unlock_irqrestore+0x11/0x30 parport_claim+0xbd/0x230 [parport] snd_mts64_probe+0x14a/0x465 [snd_mts64] platform_probe+0x3f/0xa0 really_probe+0x129/0x2c0 __driver_probe_device+0x6d/0xc0 driver_probe_device+0x1a/0xa0 __device_attach_driver+0x7a/0xb0 bus_for_each_drv+0x62/0xb0 __device_attach+0xe4/0x180 bus_probe_device+0x82/0xa0 device_add+0x550/0x920 platform_device_add+0x106/0x220 snd_mts64_attach+0x2e/0x80 [snd_mts64] port_check+0x14/0x20 [parport] bus_for_each_dev+0x6e/0xc0 __parport_register_driver+0x7c/0xb0 [parport] snd_mts64_module_init+0x31/0x1000 [snd_mts64] do_one_initcall+0x3c/0x1f0 do_init_module+0x46/0x1c6 load_module+0x1d8d/0x1e10 __do_sys_finit_module+0xa2/0xf0 do_syscall_64+0x37/0x90 entry_SYSCALL_64_after_hwframe+0x63/0xcd </TASK> Kernel panic - not syncing: Fatal exception in interrupt Rebooting in 1 seconds.. The mts wa not initialized during interrupt, we add check for mts to fix this bug. | |
| Title | ALSA: mts64: fix possible null-ptr-defer in snd_mts64_interrupt | |
| First Time appeared |
Linux
Linux linux Kernel |
|
| CPEs | cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* | |
| Vendors & Products |
Linux
Linux linux Kernel |
|
| References |
|
|
Status: PUBLISHED
Assigner: Linux
Published:
Updated: 2025-12-24T13:06:03.533Z
Reserved: 2025-12-24T13:02:21.547Z
Link: CVE-2022-50773
No data.
Status : Received
Published: 2025-12-24T13:16:04.120
Modified: 2025-12-24T13:16:04.120
Link: CVE-2022-50773
No data.
OpenCVE Enrichment
No data.