6.8-stable review patch. If anyone has any objections, please let me know.
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From: Gustavo A. R. Silva gustavoars@kernel.org
[ Upstream commit c4585edf708edb5277a3cc4b8581ccb833f3307d ]
Prepare for the coming implementation by GCC and Clang of the __counted_by attribute. Flexible array members annotated with __counted_by can have their accesses bounds-checked at run-time via CONFIG_UBSAN_BOUNDS (for array indexing) and CONFIG_FORTIFY_SOURCE (for strcpy/memcpy-family functions).
Also, -Wflex-array-member-not-at-end is coming in GCC-14, and we are getting ready to enable it globally.
So, use the `DEFINE_FLEX()` helper for multiple on-stack definitions of a flexible structure where the size of the flexible-array member is known at compile-time, and refactor the rest of the code, accordingly.
Notice that, due to the use of `__counted_by()` in `struct hci_cp_le_create_cis`, the for loop in function `hci_cs_le_create_cis()` had to be modified. Once the index `i`, through which `cp->cis[i]` is accessed, falls in the interval [0, cp->num_cis), `cp->num_cis` cannot be decremented all the way down to zero while accessing `cp->cis[]`:
net/bluetooth/hci_event.c:4310: 4310 for (i = 0; cp->num_cis; cp->num_cis--, i++) { ... 4314 handle = __le16_to_cpu(cp->cis[i].cis_handle);
otherwise, only half (one iteration before `cp->num_cis == i`) or half plus one (one iteration before `cp->num_cis < i`) of the items in the array will be accessed before running into an out-of-bounds issue. So, in order to avoid this, set `cp->num_cis` to zero just after the for loop.
Also, make use of `aux_num_cis` variable to update `cmd->num_cis` after a `list_for_each_entry_rcu()` loop.
With these changes, fix the following warnings: net/bluetooth/hci_sync.c:1239:56: warning: structure containing a flexible array member is not at the end of another structure [-Wflex-array-member-not-at-end] net/bluetooth/hci_sync.c:1415:51: warning: structure containing a flexible array member is not at the end of another structure [-Wflex-array-member-not-at-end] net/bluetooth/hci_sync.c:1731:51: warning: structure containing a flexible array member is not at the end of another structure [-Wflex-array-member-not-at-end] net/bluetooth/hci_sync.c:6497:45: warning: structure containing a flexible array member is not at the end of another structure [-Wflex-array-member-not-at-end]
Link: https://github.com/KSPP/linux/issues/202 Signed-off-by: Gustavo A. R. Silva gustavoars@kernel.org Signed-off-by: Luiz Augusto von Dentz luiz.von.dentz@intel.com Stable-dep-of: e77f43d531af ("Bluetooth: hci_core: Fix not handling hdev->le_num_of_adv_sets=1") Signed-off-by: Sasha Levin sashal@kernel.org --- include/net/bluetooth/hci.h | 8 ++-- net/bluetooth/hci_event.c | 3 +- net/bluetooth/hci_sync.c | 84 +++++++++++++++---------------------- 3 files changed, 40 insertions(+), 55 deletions(-)
diff --git a/include/net/bluetooth/hci.h b/include/net/bluetooth/hci.h index 55f95a93c0d7c..9eb3d2360b1ae 100644 --- a/include/net/bluetooth/hci.h +++ b/include/net/bluetooth/hci.h @@ -1920,7 +1920,7 @@ struct hci_cp_le_set_ext_adv_data { __u8 operation; __u8 frag_pref; __u8 length; - __u8 data[]; + __u8 data[] __counted_by(length); } __packed;
#define HCI_OP_LE_SET_EXT_SCAN_RSP_DATA 0x2038 @@ -1929,7 +1929,7 @@ struct hci_cp_le_set_ext_scan_rsp_data { __u8 operation; __u8 frag_pref; __u8 length; - __u8 data[]; + __u8 data[] __counted_by(length); } __packed;
#define HCI_OP_LE_SET_EXT_ADV_ENABLE 0x2039 @@ -1955,7 +1955,7 @@ struct hci_cp_le_set_per_adv_data { __u8 handle; __u8 operation; __u8 length; - __u8 data[]; + __u8 data[] __counted_by(length); } __packed;
#define HCI_OP_LE_SET_PER_ADV_ENABLE 0x2040 @@ -2056,7 +2056,7 @@ struct hci_cis {
struct hci_cp_le_create_cis { __u8 num_cis; - struct hci_cis cis[]; + struct hci_cis cis[] __counted_by(num_cis); } __packed;
#define HCI_OP_LE_REMOVE_CIG 0x2065 diff --git a/net/bluetooth/hci_event.c b/net/bluetooth/hci_event.c index 33fac5cab1a8d..cce73749f2dce 100644 --- a/net/bluetooth/hci_event.c +++ b/net/bluetooth/hci_event.c @@ -4250,7 +4250,7 @@ static void hci_cs_le_create_cis(struct hci_dev *hdev, u8 status) hci_dev_lock(hdev);
/* Remove connection if command failed */ - for (i = 0; cp->num_cis; cp->num_cis--, i++) { + for (i = 0; i < cp->num_cis; i++) { struct hci_conn *conn; u16 handle;
@@ -4266,6 +4266,7 @@ static void hci_cs_le_create_cis(struct hci_dev *hdev, u8 status) hci_conn_del(conn); } } + cp->num_cis = 0;
if (pending) hci_le_create_cis_pending(hdev); diff --git a/net/bluetooth/hci_sync.c b/net/bluetooth/hci_sync.c index 513b538ef9448..0525e38ba20a3 100644 --- a/net/bluetooth/hci_sync.c +++ b/net/bluetooth/hci_sync.c @@ -1235,31 +1235,27 @@ int hci_setup_ext_adv_instance_sync(struct hci_dev *hdev, u8 instance)
static int hci_set_ext_scan_rsp_data_sync(struct hci_dev *hdev, u8 instance) { - struct { - struct hci_cp_le_set_ext_scan_rsp_data cp; - u8 data[HCI_MAX_EXT_AD_LENGTH]; - } pdu; + DEFINE_FLEX(struct hci_cp_le_set_ext_scan_rsp_data, pdu, data, length, + HCI_MAX_EXT_AD_LENGTH); u8 len; struct adv_info *adv = NULL; int err;
- memset(&pdu, 0, sizeof(pdu)); - if (instance) { adv = hci_find_adv_instance(hdev, instance); if (!adv || !adv->scan_rsp_changed) return 0; }
- len = eir_create_scan_rsp(hdev, instance, pdu.data); + len = eir_create_scan_rsp(hdev, instance, pdu->data);
- pdu.cp.handle = instance; - pdu.cp.length = len; - pdu.cp.operation = LE_SET_ADV_DATA_OP_COMPLETE; - pdu.cp.frag_pref = LE_SET_ADV_DATA_NO_FRAG; + pdu->handle = instance; + pdu->length = len; + pdu->operation = LE_SET_ADV_DATA_OP_COMPLETE; + pdu->frag_pref = LE_SET_ADV_DATA_NO_FRAG;
err = __hci_cmd_sync_status(hdev, HCI_OP_LE_SET_EXT_SCAN_RSP_DATA, - sizeof(pdu.cp) + len, &pdu.cp, + struct_size(pdu, data, len), pdu, HCI_CMD_TIMEOUT); if (err) return err; @@ -1267,7 +1263,7 @@ static int hci_set_ext_scan_rsp_data_sync(struct hci_dev *hdev, u8 instance) if (adv) { adv->scan_rsp_changed = false; } else { - memcpy(hdev->scan_rsp_data, pdu.data, len); + memcpy(hdev->scan_rsp_data, pdu->data, len); hdev->scan_rsp_data_len = len; }
@@ -1411,14 +1407,10 @@ static int hci_set_per_adv_params_sync(struct hci_dev *hdev, u8 instance,
static int hci_set_per_adv_data_sync(struct hci_dev *hdev, u8 instance) { - struct { - struct hci_cp_le_set_per_adv_data cp; - u8 data[HCI_MAX_PER_AD_LENGTH]; - } pdu; + DEFINE_FLEX(struct hci_cp_le_set_per_adv_data, pdu, data, length, + HCI_MAX_PER_AD_LENGTH); u8 len;
- memset(&pdu, 0, sizeof(pdu)); - if (instance) { struct adv_info *adv = hci_find_adv_instance(hdev, instance);
@@ -1426,14 +1418,14 @@ static int hci_set_per_adv_data_sync(struct hci_dev *hdev, u8 instance) return 0; }
- len = eir_create_per_adv_data(hdev, instance, pdu.data); + len = eir_create_per_adv_data(hdev, instance, pdu->data);
- pdu.cp.length = len; - pdu.cp.handle = instance; - pdu.cp.operation = LE_SET_ADV_DATA_OP_COMPLETE; + pdu->length = len; + pdu->handle = instance; + pdu->operation = LE_SET_ADV_DATA_OP_COMPLETE;
return __hci_cmd_sync_status(hdev, HCI_OP_LE_SET_PER_ADV_DATA, - sizeof(pdu.cp) + len, &pdu, + struct_size(pdu, data, len), pdu, HCI_CMD_TIMEOUT); }
@@ -1727,31 +1719,27 @@ int hci_le_terminate_big_sync(struct hci_dev *hdev, u8 handle, u8 reason)
static int hci_set_ext_adv_data_sync(struct hci_dev *hdev, u8 instance) { - struct { - struct hci_cp_le_set_ext_adv_data cp; - u8 data[HCI_MAX_EXT_AD_LENGTH]; - } pdu; + DEFINE_FLEX(struct hci_cp_le_set_ext_adv_data, pdu, data, length, + HCI_MAX_EXT_AD_LENGTH); u8 len; struct adv_info *adv = NULL; int err;
- memset(&pdu, 0, sizeof(pdu)); - if (instance) { adv = hci_find_adv_instance(hdev, instance); if (!adv || !adv->adv_data_changed) return 0; }
- len = eir_create_adv_data(hdev, instance, pdu.data); + len = eir_create_adv_data(hdev, instance, pdu->data);
- pdu.cp.length = len; - pdu.cp.handle = instance; - pdu.cp.operation = LE_SET_ADV_DATA_OP_COMPLETE; - pdu.cp.frag_pref = LE_SET_ADV_DATA_NO_FRAG; + pdu->length = len; + pdu->handle = instance; + pdu->operation = LE_SET_ADV_DATA_OP_COMPLETE; + pdu->frag_pref = LE_SET_ADV_DATA_NO_FRAG;
err = __hci_cmd_sync_status(hdev, HCI_OP_LE_SET_EXT_ADV_DATA, - sizeof(pdu.cp) + len, &pdu.cp, + struct_size(pdu, data, len), pdu, HCI_CMD_TIMEOUT); if (err) return err; @@ -1760,7 +1748,7 @@ static int hci_set_ext_adv_data_sync(struct hci_dev *hdev, u8 instance) if (adv) { adv->adv_data_changed = false; } else { - memcpy(hdev->adv_data, pdu.data, len); + memcpy(hdev->adv_data, pdu->data, len); hdev->adv_data_len = len; }
@@ -6358,10 +6346,8 @@ static int hci_le_create_conn_sync(struct hci_dev *hdev, void *data)
int hci_le_create_cis_sync(struct hci_dev *hdev) { - struct { - struct hci_cp_le_create_cis cp; - struct hci_cis cis[0x1f]; - } cmd; + DEFINE_FLEX(struct hci_cp_le_create_cis, cmd, cis, num_cis, 0x1f); + size_t aux_num_cis = 0; struct hci_conn *conn; u8 cig = BT_ISO_QOS_CIG_UNSET;
@@ -6388,8 +6374,6 @@ int hci_le_create_cis_sync(struct hci_dev *hdev) * remains pending. */
- memset(&cmd, 0, sizeof(cmd)); - hci_dev_lock(hdev);
rcu_read_lock(); @@ -6426,7 +6410,7 @@ int hci_le_create_cis_sync(struct hci_dev *hdev) goto done;
list_for_each_entry_rcu(conn, &hdev->conn_hash.list, list) { - struct hci_cis *cis = &cmd.cis[cmd.cp.num_cis]; + struct hci_cis *cis = &cmd->cis[aux_num_cis];
if (hci_conn_check_create_cis(conn) || conn->iso_qos.ucast.cig != cig) @@ -6435,25 +6419,25 @@ int hci_le_create_cis_sync(struct hci_dev *hdev) set_bit(HCI_CONN_CREATE_CIS, &conn->flags); cis->acl_handle = cpu_to_le16(conn->parent->handle); cis->cis_handle = cpu_to_le16(conn->handle); - cmd.cp.num_cis++; + aux_num_cis++;
- if (cmd.cp.num_cis >= ARRAY_SIZE(cmd.cis)) + if (aux_num_cis >= 0x1f) break; } + cmd->num_cis = aux_num_cis;
done: rcu_read_unlock();
hci_dev_unlock(hdev);
- if (!cmd.cp.num_cis) + if (!aux_num_cis) return 0;
/* Wait for HCI_LE_CIS_Established */ return __hci_cmd_sync_status_sk(hdev, HCI_OP_LE_CREATE_CIS, - sizeof(cmd.cp) + sizeof(cmd.cis[0]) * - cmd.cp.num_cis, &cmd, - HCI_EVT_LE_CIS_ESTABLISHED, + struct_size(cmd, cis, cmd->num_cis), + cmd, HCI_EVT_LE_CIS_ESTABLISHED, conn->conn_timeout, NULL); }