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.

No CVSS v4.0

Attack Vector Local

Attack Complexity Low

Privileges Required Low

Scope Unchanged

Confidentiality Impact None

Integrity Impact None

Availability Impact High

User Interaction None

No CVSS v3.0

No CVSS v2

This CVE is not in the KEV list.

The EPSS score is 0.00049.

Key SSVC decision points have not yet been added.

Default status is the baseline for the product, each version can override it (e.g. patched versions marked unaffected).

Vendor Product Default status Versions
Linux Linux unaffected
Version Status Constraints
68ab801e32bbe2caac8b8c6e6e94f41fe7d687ad affected < 06ec592389f2be3199779ab823c4323dcfd2121f
68ab801e32bbe2caac8b8c6e6e94f41fe7d687ad affected < b471fe61da523a15e4cb60fa81f5a2377e4bad98
68ab801e32bbe2caac8b8c6e6e94f41fe7d687ad affected < 7e91667db38abb056da5a496d40fbd044c66bed2
68ab801e32bbe2caac8b8c6e6e94f41fe7d687ad affected < c7e9624d90bf20f1eed6b228949396d614b94020
68ab801e32bbe2caac8b8c6e6e94f41fe7d687ad affected < 0649129359219ce6ff380ec401f87308485c6ae3
68ab801e32bbe2caac8b8c6e6e94f41fe7d687ad affected < cba633b24a98d957e8190ef8bc4d4cdb4f6e9313
68ab801e32bbe2caac8b8c6e6e94f41fe7d687ad affected < 1a763c748acd5540ccc43306c57c9c6c5fb60884
68ab801e32bbe2caac8b8c6e6e94f41fe7d687ad affected < 250eed7b9994d79f9c409f954dbd08e88f5afd83
68ab801e32bbe2caac8b8c6e6e94f41fe7d687ad affected < cf2ea3c86ad90d63d1c572b43e1ca9276b0357ad
Linux Linux affected
Version Status Constraints
2.6.19 affected —
0 unaffected < 2.6.19
4.9.337 unaffected ≤ 4.9.*
4.14.303 unaffected ≤ 4.14.*
4.19.270 unaffected ≤ 4.19.*
5.4.229 unaffected ≤ 5.4.*
5.10.163 unaffected ≤ 5.10.*
5.15.86 unaffected ≤ 5.15.*
6.0.16 unaffected ≤ 6.0.*
6.1.2 unaffected ≤ 6.1.*
6.2 unaffected ≤ *

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Fixes

Solution

No solution given by the vendor.

Workaround

No workaround given by the vendor.

References
Link Providers
https://git.kernel.org/stable/c/0649129359219ce6ff380ec401f87308485c6ae3 cve-icon cve-icon
https://git.kernel.org/stable/c/06ec592389f2be3199779ab823c4323dcfd2121f cve-icon cve-icon
https://git.kernel.org/stable/c/1a763c748acd5540ccc43306c57c9c6c5fb60884 cve-icon cve-icon
https://git.kernel.org/stable/c/250eed7b9994d79f9c409f954dbd08e88f5afd83 cve-icon cve-icon
https://git.kernel.org/stable/c/7e91667db38abb056da5a496d40fbd044c66bed2 cve-icon cve-icon
https://git.kernel.org/stable/c/b471fe61da523a15e4cb60fa81f5a2377e4bad98 cve-icon cve-icon
https://git.kernel.org/stable/c/c7e9624d90bf20f1eed6b228949396d614b94020 cve-icon cve-icon
https://git.kernel.org/stable/c/cba633b24a98d957e8190ef8bc4d4cdb4f6e9313 cve-icon cve-icon
https://git.kernel.org/stable/c/cf2ea3c86ad90d63d1c572b43e1ca9276b0357ad cve-icon cve-icon
https://lore.kernel.org/linux-cve-announce/2025122459-CVE-2022-50773-b946@gregkh/T cve-icon
https://nvd.nist.gov/vuln/detail/CVE-2022-50773 cve-icon
https://www.cve.org/CVERecord?id=CVE-2022-50773 cve-icon
History

Thu, 25 Dec 2025 00:15:00 +0000

Type Values Removed Values Added
References
Metrics threat_severity

None

 cvssV3_1

{'score': 5.5, 'vector': 'CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H'}

threat_severity

Low

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

Projects

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cve-icon MITRE

Status: PUBLISHED

Assigner: Linux

Published:

Updated: 2025-12-24T13:06:03.533Z

Reserved: 2025-12-24T13:02:21.547Z

Link: CVE-2022-50773

cve-icon Vulnrichment

No data.

cve-icon NVD

Status : Awaiting Analysis

Published: 2025-12-24T13:16:04.120

Modified: 2025-12-29T15:58:34.503

Link: CVE-2022-50773

cve-icon Redhat

Severity : Low

Publid Date: 2025-12-24T00:00:00Z

Links: CVE-2022-50773 - Bugzilla

cve-icon OpenCVE Enrichment

No data.

Weaknesses

No weakness.