CVE-2026-90224: nfc: nci: fix double completion race in nci_data_exchange_complete

Severity: high (CVSS 7.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.4% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-09-17 · updated 2026-10-19

Description

In the Linux kernel, the following vulnerability has been resolved: nfc: nci: fix double completion race in nci_data_exchange_complete nci_close_device() and nci_rx_work can both call nci_data_exchange_complete() concurrently. After commit 4527025d440ce8 ("nfc: nci: fix circular locking dependency in nci_close_device") moved flush_workqueue(ndev->rx_wq) after mutex_unlock(&ndev->req_lock), rx_work is no longer serialized with the explicit completion call in the close path. Both callers read the non-NULL callback pointer and invoke rawsock_data_exchange_complete(), which calls sock_put() -- but only one sock_hold() was taken, so the second sock_put() underflows the refcount and frees the socket while it is still in use. Replace the bare clear_bit(NCI_DATA_EXCHANGE) with test_and_clear_bit() so that only the first caller proceeds to invoke the callback.

Affected products

Linux kernel: from 5.10.253 before 5.10.270; from 5.15.203 before 5.15.221; from 6.1.168 before 6.1.188; from 6.6.131 before 6.6.157; from 6.12.80 before 6.12.110; from 6.18.21 before 6.18.52 — fixed in 5.10.270, 5.15.221, 6.1.188, 6.12.110, 6.18.52, 6.20

How to fix

Upgrade to a fixed version: Linux kernel 5.10.270, 5.15.221, 6.1.188, 6.12.110. Check the vendor advisory for mitigations.

References

Get alerted when CVE-2026-90224 or the next vulnerability affects your stack