{"cve":"CVE-2022-50773","nvd":{"published":"2025-12-24T13:16:04.120","modified":"2026-06-17T05:24:09.207","status":"Deferred","description":"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>test_mod1.sh<<EOF\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  <IRQ>\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  </IRQ>\n  <TASK>\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  </TASK>\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.","cvss_v4":null,"cvss_v3":null,"cwes":[],"references":["https://git.kernel.org/stable/c/0649129359219ce6ff380ec401f87308485c6ae3","https://git.kernel.org/stable/c/06ec592389f2be3199779ab823c4323dcfd2121f","https://git.kernel.org/stable/c/1a763c748acd5540ccc43306c57c9c6c5fb60884","https://git.kernel.org/stable/c/250eed7b9994d79f9c409f954dbd08e88f5afd83","https://git.kernel.org/stable/c/7e91667db38abb056da5a496d40fbd044c66bed2"],"products":[],"source":"nvd","synced_at":"2026-10-19T22:18:08.089039631+00:00"},"epss":{"cve":"CVE-2022-50773","score":0.00284,"percentile":0.20957,"date":"2026-10-31"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}