Bug 2436830 (CVE-2026-23108)

Summary: CVE-2026-23108 kernel: can: usb_8dev: usb_8dev_read_bulk_callback(): fix URB memory leak
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security DevOps Team <prodsec-dev>
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Priority: medium    
Version: unspecifiedKeywords: Security
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Hardware: All   
OS: Linux   
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A memory leak vulnerability was found in the Linux kernel's USB 8devices CAN adapter driver. The URBs allocated for USB-in transfers are unanchored by the USB framework before the completion callback is invoked. Since usb_8dev_read_bulk_callback() does not re-anchor the URBs, they are never freed when usb_kill_anchored_urbs() is called during device close, causing a memory leak on each open/close cycle.
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Description OSIDB Bzimport 2026-02-04 17:05:30 UTC
In the Linux kernel, the following vulnerability has been resolved:

can: usb_8dev: usb_8dev_read_bulk_callback(): fix URB memory leak

Fix similar memory leak as in commit 7352e1d5932a ("can: gs_usb:
gs_usb_receive_bulk_callback(): fix URB memory leak").

In usb_8dev_open() -> usb_8dev_start(), the URBs for USB-in transfers are
allocated, added to the priv->rx_submitted anchor and submitted. In the
complete callback usb_8dev_read_bulk_callback(), the URBs are processed and
resubmitted. In usb_8dev_close() -> unlink_all_urbs() the URBs are freed by
calling usb_kill_anchored_urbs(&priv->rx_submitted).

However, this does not take into account that the USB framework unanchors
the URB before the complete function is called. This means that once an
in-URB has been completed, it is no longer anchored and is ultimately not
released in usb_kill_anchored_urbs().

Fix the memory leak by anchoring the URB in the
usb_8dev_read_bulk_callback() to the priv->rx_submitted anchor.