linux/net/bluetooth/eir.h
Luiz Augusto von Dentz 47c0390226 Bluetooth: eir: Fix possible crashes on eir_create_adv_data
eir_create_adv_data may attempt to add EIR_FLAGS and EIR_TX_POWER
without checking if that would fit.

Link: https://github.com/bluez/bluez/issues/1117#issuecomment-2958244066
Fixes: 01ce70b0a2 ("Bluetooth: eir: Move EIR/Adv Data functions to its own file")
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
2025-06-11 16:29:22 -04:00

99 lines
2.1 KiB
C

/* SPDX-License-Identifier: GPL-2.0 */
/*
* BlueZ - Bluetooth protocol stack for Linux
*
* Copyright (C) 2021 Intel Corporation
*/
#include <linux/unaligned.h>
void eir_create(struct hci_dev *hdev, u8 *data);
u8 eir_create_adv_data(struct hci_dev *hdev, u8 instance, u8 *ptr, u8 size);
u8 eir_create_scan_rsp(struct hci_dev *hdev, u8 instance, u8 *ptr);
u8 eir_create_per_adv_data(struct hci_dev *hdev, u8 instance, u8 *ptr);
u8 eir_append_local_name(struct hci_dev *hdev, u8 *eir, u8 ad_len);
u8 eir_append_appearance(struct hci_dev *hdev, u8 *ptr, u8 ad_len);
u8 eir_append_service_data(u8 *eir, u16 eir_len, u16 uuid, u8 *data,
u8 data_len);
static inline u16 eir_precalc_len(u8 data_len)
{
return sizeof(u8) * 2 + data_len;
}
static inline u16 eir_append_data(u8 *eir, u16 eir_len, u8 type,
u8 *data, u8 data_len)
{
eir[eir_len++] = sizeof(type) + data_len;
eir[eir_len++] = type;
memcpy(&eir[eir_len], data, data_len);
eir_len += data_len;
return eir_len;
}
static inline u16 eir_append_le16(u8 *eir, u16 eir_len, u8 type, u16 data)
{
eir[eir_len++] = sizeof(type) + sizeof(data);
eir[eir_len++] = type;
put_unaligned_le16(data, &eir[eir_len]);
eir_len += sizeof(data);
return eir_len;
}
static inline u16 eir_skb_put_data(struct sk_buff *skb, u8 type, u8 *data, u8 data_len)
{
u8 *eir;
u16 eir_len;
eir_len = eir_precalc_len(data_len);
eir = skb_put(skb, eir_len);
WARN_ON(sizeof(type) + data_len > U8_MAX);
eir[0] = sizeof(type) + data_len;
eir[1] = type;
memcpy(&eir[2], data, data_len);
return eir_len;
}
static inline void *eir_get_data(u8 *eir, size_t eir_len, u8 type,
size_t *data_len)
{
size_t parsed = 0;
if (eir_len < 2)
return NULL;
while (parsed < eir_len - 1) {
u8 field_len = eir[0];
if (field_len == 0)
break;
parsed += field_len + 1;
if (parsed > eir_len)
break;
if (eir[1] != type) {
eir += field_len + 1;
continue;
}
/* Zero length data */
if (field_len == 1)
return NULL;
if (data_len)
*data_len = field_len - 1;
return &eir[2];
}
return NULL;
}
void *eir_get_service_data(u8 *eir, size_t eir_len, u16 uuid, size_t *len);