CVE-2026-64327 — usb: gadget: f_fs: Initialize epfile->in early to fix endpoint direction checks
In the Linux kernel, the following vulnerability has been resolved: usb: gadget: f_fs: Initialize epfile->in early to fix endpoint direction checks When parsing endpoint descr…
Published: 2026-07-25 · CVSS: Unscored
In the Linux kernel, the following vulnerability has been resolved: usb: gadget: f_fs: Initialize epfile->in early to fix endpoint direction checks When parsing endpoint descriptors, ffs_data_got_descs() generates the eps_addrmap which contains the endpoint direction. However, epfile->in was previously only populated in ffs_func_eps_enable() which executes upon USB host connection. As a result, early userspace ioctls like FUNCTIONFS_DMABUF_ATTACH that run before the host connects would see epfile->in as 0, leading to incorrect DMA directions. By moving the initialization to ffs_epfiles_create(), epfile->in is accurate before userspace opens the endpoint files.
Source: CVE Program · Revision 8b16575c39f1e1810c5e863010da073d2d3285e7