ALSA: mts64: fix possible null-ptr-defer in snd_mts64_interrupt

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.

Timeline

Scores

No CVSS score yet: neither the CNA, CISA nor NVD has scored this CVE. NVD status: Deferred.

EPSS (exploitation in 30 days)

0.28% · top 79% of all CVEs (7 Nov 2026)

The list uses the assigner's score when there is one, then CISA's, then NVD's: Not scored.

Affected products

• Linux · Linux

  • affected 68ab801e32bbe2caac8b8c6e6e94f41fe7d687ad – < 06ec592389f2be3199779ab823c4323dcfd2121f
  • affected 68ab801e32bbe2caac8b8c6e6e94f41fe7d687ad – < b471fe61da523a15e4cb60fa81f5a2377e4bad98
  • affected 68ab801e32bbe2caac8b8c6e6e94f41fe7d687ad – < 7e91667db38abb056da5a496d40fbd044c66bed2
  • affected 68ab801e32bbe2caac8b8c6e6e94f41fe7d687ad – < c7e9624d90bf20f1eed6b228949396d614b94020
  • affected 68ab801e32bbe2caac8b8c6e6e94f41fe7d687ad – < 0649129359219ce6ff380ec401f87308485c6ae3
  • affected 68ab801e32bbe2caac8b8c6e6e94f41fe7d687ad – < cba633b24a98d957e8190ef8bc4d4cdb4f6e9313
  • affected 68ab801e32bbe2caac8b8c6e6e94f41fe7d687ad – < 1a763c748acd5540ccc43306c57c9c6c5fb60884
  • affected 68ab801e32bbe2caac8b8c6e6e94f41fe7d687ad – < 250eed7b9994d79f9c409f954dbd08e88f5afd83
  • affected 68ab801e32bbe2caac8b8c6e6e94f41fe7d687ad – < cf2ea3c86ad90d63d1c572b43e1ca9276b0357ad

• Linux · Linux

  • affected 2.6.19
  • unaffected < 2.6.19
  • unaffected 4.9.337 – ≤ 4.9.*
  • unaffected 4.14.303 – ≤ 4.14.*
  • unaffected 4.19.270 – ≤ 4.19.*
  • unaffected 5.4.229 – ≤ 5.4.*
  • unaffected 5.10.163 – ≤ 5.10.*
  • unaffected 5.15.86 – ≤ 5.15.*
  • unaffected 6.0.16 – ≤ 6.0.*
  • unaffected 6.1.2 – ≤ 6.1.*
  • unaffected 6.2 – ≤ *

References (9)

• https://git.kernel.org/stable/c/06ec592389f2be3199779ab823c4323dcfd2121f (opens in a new tab)
• https://git.kernel.org/stable/c/b471fe61da523a15e4cb60fa81f5a2377e4bad98 (opens in a new tab)
• https://git.kernel.org/stable/c/7e91667db38abb056da5a496d40fbd044c66bed2 (opens in a new tab)
• https://git.kernel.org/stable/c/c7e9624d90bf20f1eed6b228949396d614b94020 (opens in a new tab)
• https://git.kernel.org/stable/c/0649129359219ce6ff380ec401f87308485c6ae3 (opens in a new tab)
• https://git.kernel.org/stable/c/cba633b24a98d957e8190ef8bc4d4cdb4f6e9313 (opens in a new tab)
• https://git.kernel.org/stable/c/1a763c748acd5540ccc43306c57c9c6c5fb60884 (opens in a new tab)
• https://git.kernel.org/stable/c/250eed7b9994d79f9c409f954dbd08e88f5afd83 (opens in a new tab)
• https://git.kernel.org/stable/c/cf2ea3c86ad90d63d1c572b43e1ca9276b0357ad (opens in a new tab)

Sources

The same CVE in the primary databases and aggregators, to check against.

• CVE.org record (opens in a new tab)
• CVE List JSON (GitHub) (opens in a new tab)
• NVD (opens in a new tab)
• FIRST EPSS (opens in a new tab)
• OSV.dev (opens in a new tab)
• GitHub Advisories (opens in a new tab)
• CIRCL Vulnerability-Lookup (opens in a new tab)

Badge for a README or a ticket

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Record last updated 11 May 2026, 19:25 UTC.