{"id":"CVE-2022-50773","summary":"ALSA: mts64: fix possible null-ptr-defer in snd_mts64_interrupt","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nALSA: mts64: fix possible null-ptr-defer in snd_mts64_interrupt\n\nI got a null-ptr-defer error report when I do the following tests\non the qemu platform:\n\nmake defconfig and CONFIG_PARPORT=m, CONFIG_PARPORT_PC=m,\nCONFIG_SND_MTS64=m\n\nThen making test scripts:\ncat\u003etest_mod1.sh\u003c\u003cEOF\nmodprobe snd-mts64\nmodprobe snd-mts64\nEOF\n\nExecuting the script, perhaps several times, we will get a null-ptr-defer\nreport, as follow:\n\nsyzkaller:~# ./test_mod.sh\nsnd_mts64: probe of snd_mts64.0 failed with error -5\nmodprobe: ERROR: could not insert 'snd_mts64': No such device\n BUG: kernel NULL pointer dereference, address: 0000000000000000\n #PF: supervisor write access in kernel mode\n #PF: error_code(0x0002) - not-present page\n PGD 0 P4D 0\n Oops: 0002 [#1] PREEMPT SMP PTI\n CPU: 0 PID: 205 Comm: modprobe Not tainted 6.1.0-rc8-00588-g76dcd734eca2 #6\n Call Trace:\n  \u003cIRQ\u003e\n  snd_mts64_interrupt+0x24/0xa0 [snd_mts64]\n  parport_irq_handler+0x37/0x50 [parport]\n  __handle_irq_event_percpu+0x39/0x190\n  handle_irq_event_percpu+0xa/0x30\n  handle_irq_event+0x2f/0x50\n  handle_edge_irq+0x99/0x1b0\n  __common_interrupt+0x5d/0x100\n  common_interrupt+0xa0/0xc0\n  \u003c/IRQ\u003e\n  \u003cTASK\u003e\n  asm_common_interrupt+0x22/0x40\n RIP: 0010:_raw_write_unlock_irqrestore+0x11/0x30\n  parport_claim+0xbd/0x230 [parport]\n  snd_mts64_probe+0x14a/0x465 [snd_mts64]\n  platform_probe+0x3f/0xa0\n  really_probe+0x129/0x2c0\n  __driver_probe_device+0x6d/0xc0\n  driver_probe_device+0x1a/0xa0\n  __device_attach_driver+0x7a/0xb0\n  bus_for_each_drv+0x62/0xb0\n  __device_attach+0xe4/0x180\n  bus_probe_device+0x82/0xa0\n  device_add+0x550/0x920\n  platform_device_add+0x106/0x220\n  snd_mts64_attach+0x2e/0x80 [snd_mts64]\n  port_check+0x14/0x20 [parport]\n  bus_for_each_dev+0x6e/0xc0\n  __parport_register_driver+0x7c/0xb0 [parport]\n  snd_mts64_module_init+0x31/0x1000 [snd_mts64]\n  do_one_initcall+0x3c/0x1f0\n  do_init_module+0x46/0x1c6\n  load_module+0x1d8d/0x1e10\n  __do_sys_finit_module+0xa2/0xf0\n  do_syscall_64+0x37/0x90\n  entry_SYSCALL_64_after_hwframe+0x63/0xcd\n  \u003c/TASK\u003e\n Kernel panic - not syncing: Fatal exception in interrupt\n Rebooting in 1 seconds..\n\nThe mts wa not initialized during interrupt,  we add check for\nmts to fix this bug.","modified":"2026-03-20T11:47:36.868492Z","published":"2025-12-24T13:06:03.533Z","related":["SUSE-SU-2026:0263-1","SUSE-SU-2026:0317-1","SUSE-SU-2026:0411-1","SUSE-SU-2026:0617-1"],"database_specific":{"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2022/50xxx/CVE-2022-50773.json","cna_assigner":"Linux"},"references":[{"type":"WEB","url":"https://git.kernel.org/stable/c/0649129359219ce6ff380ec401f87308485c6ae3"},{"type":"WEB","url":"https://git.kernel.org/stable/c/06ec592389f2be3199779ab823c4323dcfd2121f"},{"type":"WEB","url":"https://git.kernel.org/stable/c/1a763c748acd5540ccc43306c57c9c6c5fb60884"},{"type":"WEB","url":"https://git.kernel.org/stable/c/250eed7b9994d79f9c409f954dbd08e88f5afd83"},{"type":"WEB","url":"https://git.kernel.org/stable/c/7e91667db38abb056da5a496d40fbd044c66bed2"},{"type":"WEB","url":"https://git.kernel.org/stable/c/b471fe61da523a15e4cb60fa81f5a2377e4bad98"},{"type":"WEB","url":"https://git.kernel.org/stable/c/c7e9624d90bf20f1eed6b228949396d614b94020"},{"type":"WEB","url":"https://git.kernel.org/stable/c/cba633b24a98d957e8190ef8bc4d4cdb4f6e9313"},{"type":"WEB","url":"https://git.kernel.org/stable/c/cf2ea3c86ad90d63d1c572b43e1ca9276b0357ad"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2022/50xxx/CVE-2022-50773.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2022-50773"},{"type":"PACKAGE","url":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","events":[{"introduced":"68ab801e32bbe2caac8b8c6e6e94f41fe7d687ad"},{"fixed":"06ec592389f2be3199779ab823c4323dcfd2121f"},{"fixed":"b471fe61da523a15e4cb60fa81f5a2377e4bad98"},{"fixed":"7e91667db38abb056da5a496d40fbd044c66bed2"},{"fixed":"c7e9624d90bf20f1eed6b228949396d614b94020"},{"fixed":"0649129359219ce6ff380ec401f87308485c6ae3"},{"fixed":"cba633b24a98d957e8190ef8bc4d4cdb4f6e9313"},{"fixed":"1a763c748acd5540ccc43306c57c9c6c5fb60884"},{"fixed":"250eed7b9994d79f9c409f954dbd08e88f5afd83"},{"fixed":"cf2ea3c86ad90d63d1c572b43e1ca9276b0357ad"}]}],"database_specific":{"source":"https://storage.googleapis.com/osv-test-cve-osv-conversion/osv-output/CVE-2022-50773.json"}},{"package":{"name":"Kernel","ecosystem":"Linux"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"2.6.19"},{"fixed":"4.9.337"}]},{"type":"ECOSYSTEM","events":[{"introduced":"4.10.0"},{"fixed":"4.14.303"}]},{"type":"ECOSYSTEM","events":[{"introduced":"4.15.0"},{"fixed":"4.19.270"}]},{"type":"ECOSYSTEM","events":[{"introduced":"4.20.0"},{"fixed":"5.4.229"}]},{"type":"ECOSYSTEM","events":[{"introduced":"5.5.0"},{"fixed":"5.10.163"}]},{"type":"ECOSYSTEM","events":[{"introduced":"5.11.0"},{"fixed":"5.15.86"}]},{"type":"ECOSYSTEM","events":[{"introduced":"5.16.0"},{"fixed":"6.0.16"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.1.0"},{"fixed":"6.1.2"}]}],"database_specific":{"source":"https://storage.googleapis.com/osv-test-cve-osv-conversion/osv-output/CVE-2022-50773.json"}}],"schema_version":"1.7.5"}