CVE-2026-64327

Name	CVE-2026-64327
Description	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 (at NVD; CERT, ENISA, LWN, oss-sec, fulldisc, Debian ELTS, Red Hat, Ubuntu, Gentoo, SUSE bugzilla/CVE, GitHub advisories/code/issues, web search, more)
References	DLA-4724-1

Vulnerable and fixed packages

The table below lists information on source packages.

Source Package	Release	Version	Status
linux (PTS)	bullseye	5.10.223-1	fixed
	bullseye (security)	5.10.262-1	fixed
	bookworm	6.1.176-1	fixed
	bookworm (security)	6.1.180-1	fixed
	trixie	6.12.94-1	vulnerable
	trixie (security)	6.12.101-1	fixed
	forky	7.1.7-1	fixed
	sid	7.1.8-1	fixed
linux-6.12 (PTS)	bookworm (security)	6.12.100-1~deb12u1	fixed

The information below is based on the following data on fixed versions.

Package	Type	Release	Fixed Version	Origin
linux	source	bullseye	(not affected)
linux	source	bookworm	(not affected)
linux	source	trixie	6.12.96-1
linux	source	(unstable)	7.1.4-1
linux-6.12	source	bookworm	6.12.100-1~deb12u1	DLA-4724-1

Notes

[bookworm] - linux <not-affected> (Vulnerable code not present)
[bullseye] - linux <not-affected> (Vulnerable code not present)
https://git.kernel.org/linus/82cfd4739011bdc7e87b5d585703427e89ddfaa5 (7.2-rc3)