CVE-2026-63915nfc: hci: fix out-of-bounds read in HCP header parsing

Official description

In the Linux kernel, the following vulnerability has been resolved: nfc: hci: fix out-of-bounds read in HCP header parsing Both nfc_hci_recv_from_llc() and nci_hci_data_received_cb() read packet->header from skb->data at function entry without first checking that the buffer holds at least one byte. A malicious NFC peer can send a 0-byte HCP frame that passes through the SHDLC layer and reaches these functions, causing an out-of-bounds heap read of packet->header. The same 0-byte frame, if queued as a non-final fragment, also causes the reassembly loop to underflow msg_len to UINT_MAX, triggering skb_over_panic() when the reassembled skb is written. Fix this by adding a pskb_may_pull() check at the entry of each function before packet->header is first accessed. The existing pskb_may_pull() checks before the reassembled hcp_skb is cast to struct hcp_packet remain in place to guard the 2-byte HCP message header.

Affected packages & fixed versions

Affected products (as reported)

References

• https://git.kernel.org/stable/c/ed6d5d97dad0334a7f43d218753429cbe2f70a4f
• https://git.kernel.org/stable/c/b99366d74b535d0cadb1ef73e04639415d9ff3b7
• https://git.kernel.org/stable/c/37382293f174b82a0616c8295e32b1fc8e13d1ed
• https://git.kernel.org/stable/c/c4cc6b3b0013acb3ed0b2b60e57dfae98647fe98
• https://git.kernel.org/stable/c/1905f5ec3641b2b234bb63549c8ca11ab85466eb
• https://git.kernel.org/stable/c/22d41b176b9989efd21c3b2d3abf6728f05b9d9a
• https://git.kernel.org/stable/c/83b1362edc9d6ae376c6f36da116e2c70f2e70a6
• https://git.kernel.org/stable/c/f040e590c035bfd9553fe79ee9585caf1b14d67b