CVE-2026-68312

About vulnerability

In the Linux kernel, the following vulnerability has been resolved:

cifs: fix cifsFileInfo leak on kmalloc failure in deferred close drain paths

In cifs_close_deferred_file(), cifs_close_all_deferred_files(), and cifs_close_deferred_file_under_dentry(), when a pending deferred close is cancelled via cancel_delayed_work(), the subsequent kmalloc_obj() to add the file to the local processing list may fail under memory pressure. The loop breaks immediately, but the cancelled work is no longer pending (it would have called _cifsFileInfo_put()), and the cfile is never added to file_head for processing. The cifsFileInfo reference and the open server handle both leak.

Fix by saving the cfile that failed allocation in a local variable, breaking as before, and calling _cifsFileInfo_put() on it after releasing the lock. Any files later in the iteration are unaffected since their deferred work is still pending and will fire normally.

Affected product:

AlmaLinux 9.2 ESU , Debian 10 ELS , TuxCare 9.6 ESU , TuxCare 9.8 ESU

Affected packages:

linux @ 4.19.0 (+3 more)

Live-patch status from KernelCare for each operating system.