CVE-2026-89583Bluetooth: eir: Fix OOB read in eir_get_service_data()

Official description

In the Linux kernel, the following vulnerability has been resolved: Bluetooth: eir: Fix OOB read in eir_get_service_data() eir_get_service_data() walks the advertising data for a Service Data field with a matching UUID. On a mismatch it advances: eir += dlen; eir_len -= dlen; eir_get_data() reports dlen as the field's data length, but the field spans dlen + 2 bytes once its length and type bytes count, and more when non-Service-Data fields were skipped to reach it. The pointer lands correctly on the next field. eir_len does not, and the shortfall compounds across fields until eir_get_data() reads the length and type bytes of a "field" past the end of the buffer. For an ISO broadcast sink that buffer is hcon->le_per_adv_data[], filled from the periodic advertising reports of a remote broadcaster. A PA payload packed with mismatching Service Data fields walks off the array into the rest of struct hci_conn. A drifted field that matches the BAA UUID puts those bytes in iso_pi(sk)->base, where user space reads them back with getsockopt(BT_ISO_BASE). Recompute eir_len from the end of the buffer each iteration.

Affected packages & fixed versions

Affected products (as reported)

References

• https://git.kernel.org/stable/c/b6902adf81ea2ce14b1040dd97b6980050a8125a
• https://git.kernel.org/stable/c/1a28aae7f1fc8c06c0d02f153541be4fc7bacb74
• https://git.kernel.org/stable/c/815fc98c227a78cbd93d4c29f2833705b7c2bc0f
• https://git.kernel.org/stable/c/c21fa79301d7d6ac0a4ec6c51e8ba10beaa08c50
• https://git.kernel.org/stable/c/bb56e97bd67614238c1c0a4084704ccadbb875b4
• https://git.kernel.org/stable/c/4beb198bc59b242404a47c21990bc84165052c8a