{"cve":"CVE-2022-50620","nvd":{"published":"2025-12-08T02:15:47.870","modified":"2026-06-17T05:23:52.840","status":"Deferred","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nf2fs: fix to invalidate dcc->f2fs_issue_discard in error path\n\nSyzbot reports a NULL pointer dereference issue as below:\n\n __refcount_add include/linux/refcount.h:193 [inline]\n __refcount_inc include/linux/refcount.h:250 [inline]\n refcount_inc include/linux/refcount.h:267 [inline]\n get_task_struct include/linux/sched/task.h:110 [inline]\n kthread_stop+0x34/0x1c0 kernel/kthread.c:703\n f2fs_stop_discard_thread+0x3c/0x5c fs/f2fs/segment.c:1638\n kill_f2fs_super+0x5c/0x194 fs/f2fs/super.c:4522\n deactivate_locked_super+0x70/0xe8 fs/super.c:332\n deactivate_super+0xd0/0xd4 fs/super.c:363\n cleanup_mnt+0x1f8/0x234 fs/namespace.c:1186\n __cleanup_mnt+0x20/0x30 fs/namespace.c:1193\n task_work_run+0xc4/0x14c kernel/task_work.c:177\n exit_task_work include/linux/task_work.h:38 [inline]\n do_exit+0x26c/0xbe0 kernel/exit.c:795\n do_group_exit+0x60/0xe8 kernel/exit.c:925\n __do_sys_exit_group kernel/exit.c:936 [inline]\n __se_sys_exit_group kernel/exit.c:934 [inline]\n __wake_up_parent+0x0/0x40 kernel/exit.c:934\n __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]\n invoke_syscall arch/arm64/kernel/syscall.c:52 [inline]\n el0_svc_common+0x138/0x220 arch/arm64/kernel/syscall.c:142\n do_el0_svc+0x48/0x164 arch/arm64/kernel/syscall.c:206\n el0_svc+0x58/0x150 arch/arm64/kernel/entry-common.c:636\n el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:654\n el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:581\n\nThe root cause of this issue is in error path of f2fs_start_discard_thread(),\nit missed to invalidate dcc->f2fs_issue_discard, later kthread_stop() may\naccess invalid pointer.","cvss_v4":null,"cvss_v3":null,"cwes":[],"references":["https://git.kernel.org/stable/c/865bb7b5a7deeb0e5afbd82381d52d38825dc64d","https://git.kernel.org/stable/c/91586ce0d39a05f88795aa8814fb99b1387236b3","https://git.kernel.org/stable/c/a3e517a6ba695d683ee63615e1ea6e6b4c7d2732","https://git.kernel.org/stable/c/ae6c960a82c52c3bda5adc82d90643d6c12d308e"],"products":[],"source":"nvd","synced_at":"2026-10-19T22:16:40.427100871+00:00"},"epss":{"cve":"CVE-2022-50620","score":0.00199,"percentile":0.09808,"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."]}