CVE-2026-68178

01/Description

In the Linux kernel, the following vulnerability has been resolved: misc: nsm: pin the module while the device is open misc_open() installs a misc driver's file operations with fops_get(), which pins file_operations::owner before replacing the file's f_op. The NSM misc device leaves nsm_dev_fops.owner unset, so opening /dev/nsm does not take a module reference on the nsm driver. If the driver is built as a module, an open file descriptor can therefore survive rmmod of the module that provides its ioctl callbacks. A later ioctl through that descriptor can call into unloaded module text. Set nsm_dev_fops.owner to THIS_MODULE so the misc core holds the module while any /dev/nsm file descriptor is open, matching the lifetime expectation for the installed file operations.

02/References4

• git.kernel.org/stable/c/1996639f824ce9468395cdb7bcb8f467fa787e77
• git.kernel.org/stable/c/1da310b94504d42001e9c32c43c5dc105b777e5f
• git.kernel.org/stable/c/3b231f1e9990f4c21220d0a69733ce2105891ff9
• git.kernel.org/stable/c/9e9a82d00c3d10129fc310a7547b24a679d5d920