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

usb: gadget: f_fs: Fix epfile null pointer access after ep enable.

A race condition occurs when ffs_func_eps_enable() runs concurrently
with ffs_data_reset(). The ffs_data_clear() called in ffs_data_reset()
sets ffs->epfiles to NULL before resetting ffs->eps_count to 0, leading
to a NULL pointer dereference when accessing epfile->ep in
ffs_func_eps_enable() after successful usb_ep_enable().

The ffs->epfiles pointer is set to NULL in both ffs_data_clear() and
ffs_data_close() functions, and its modification is protected by the
spinlock ffs->eps_lock. And the whole ffs_func_eps_enable() function
is also protected by ffs->eps_lock.

Thus, add NULL pointer handling for ffs->epfiles in the
ffs_func_eps_enable() function to fix issues
Advisories

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Fixes

Solution

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Workaround

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History

Mon, 08 Dec 2025 01:15:00 +0000

Type Values Removed Values Added
Description In the Linux kernel, the following vulnerability has been resolved: usb: gadget: f_fs: Fix epfile null pointer access after ep enable. A race condition occurs when ffs_func_eps_enable() runs concurrently with ffs_data_reset(). The ffs_data_clear() called in ffs_data_reset() sets ffs->epfiles to NULL before resetting ffs->eps_count to 0, leading to a NULL pointer dereference when accessing epfile->ep in ffs_func_eps_enable() after successful usb_ep_enable(). The ffs->epfiles pointer is set to NULL in both ffs_data_clear() and ffs_data_close() functions, and its modification is protected by the spinlock ffs->eps_lock. And the whole ffs_func_eps_enable() function is also protected by ffs->eps_lock. Thus, add NULL pointer handling for ffs->epfiles in the ffs_func_eps_enable() function to fix issues
Title usb: gadget: f_fs: Fix epfile null pointer access after ep enable.
First Time appeared Linux
Linux linux Kernel
CPEs cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
Vendors & Products Linux
Linux linux Kernel
References

Projects

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cve-icon MITRE

Status: PUBLISHED

Assigner: Linux

Published:

Updated: 2025-12-08T00:46:41.896Z

Reserved: 2025-04-16T07:20:57.186Z

Link: CVE-2025-40315

cve-icon Vulnrichment

No data.

cve-icon NVD

Status : Received

Published: 2025-12-08T01:16:04.013

Modified: 2025-12-08T01:16:04.013

Link: CVE-2025-40315

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

No data.

Weaknesses

No weakness.