CVE-2026-31629

Summary

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

nfc: llcp: add missing return after LLCP_CLOSED checks

In nfc_llcp_recv_hdlc() and nfc_llcp_recv_disc(), when the socket state is LLCP_CLOSED, the code correctly calls release_sock() and nfc_llcp_sock_put() but fails to return. Execution falls through to the remainder of the function, which calls release_sock() and nfc_llcp_sock_put() again. This results in a double release_sock() and a refcount underflow via double nfc_llcp_sock_put(), leading to a use-after-free.

Add the missing return statements after the LLCP_CLOSED branches in both functions to prevent the fall-through.

Affected Software

VendorProductVersion RangeStatus
LinuxLinuxd646960f7986fefb460a2b062d5ccc8ccfeacc3a < b2a23529593d011fb433a3d711fc597ed6a6bd2faffected
LinuxLinuxd646960f7986fefb460a2b062d5ccc8ccfeacc3a < 665315df9c3486cb213fc44d83cc8bcd47fe0d26affected
LinuxLinuxd646960f7986fefb460a2b062d5ccc8ccfeacc3a < 9b49e2a4b8219a2fc5cebf94f4ec34e509aff8a6affected
LinuxLinuxd646960f7986fefb460a2b062d5ccc8ccfeacc3a < 0eb1263a3b8c36418c9ba295c9ab3abed664edbfaffected
LinuxLinuxd646960f7986fefb460a2b062d5ccc8ccfeacc3a < 796e0cac058252d0ad34ebe288e6f7979b5fc9b2affected
LinuxLinuxd646960f7986fefb460a2b062d5ccc8ccfeacc3a < 8977fad2b3c6eefd414131168d597c5d1d5e1abfaffected
LinuxLinuxd646960f7986fefb460a2b062d5ccc8ccfeacc3a < ff3d9e8f7244293e303f7b6ef70774291c7c27e9affected
LinuxLinuxd646960f7986fefb460a2b062d5ccc8ccfeacc3a < aba4712e8f0381cd5d196534ce2ad082626a5ab6affected
LinuxLinuxd646960f7986fefb460a2b062d5ccc8ccfeacc3a < 2b5dd4632966c39da6ba74dbc8689b309065e82caffected
LinuxLinux3.3affected
LinuxLinux0 < 3.3unaffected
LinuxLinux5.10.258 <= 5.10.*unaffected
LinuxLinux5.15.209 <= 5.15.*unaffected
LinuxLinux6.1.175 <= 6.1.*unaffected
LinuxLinux6.6.136 <= 6.6.*unaffected
LinuxLinux6.12.83 <= 6.12.*unaffected
LinuxLinux6.18.24 <= 6.18.*unaffected
LinuxLinux6.19.14 <= 6.19.*unaffected
LinuxLinux7.0.1 <= 7.0.*unaffected
LinuxLinux7.1 <= *unaffected

Weaknesses

References