| Message ID | ZjO9qCx10KUJbK6w@neat (mailing list archive) |
|---|---|
| State | Awaiting Upstream |
| Delegated to: | Netdev Maintainers |
| Headers | show |
| Series | [next] Bluetooth: hci_conn: Use __counted_by() and avoid -Wfamnae warning | expand |
On Thu, May 02, 2024 at 10:22:00AM -0600, Gustavo A. R. Silva wrote: > 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 an on-stack definition 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. > > With these changes, fix the following warning: > net/bluetooth/hci_conn.c:669:41: 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> Nice! This looks really clean; I'll point people at this patch when they want to see these kinds of conversions. It has it all! :) Reviewed-by: Kees Cook <keescook@chromium.org>
>> So, use the `DEFINE_FLEX()` helper for an on-stack definition 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. >> >> With these changes, fix the following warning: >> net/bluetooth/hci_conn.c:669:41: 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> > > Nice! This looks really clean; I'll point people at this patch when they > want to see these kinds of conversions. It has it all! :) I really enjoyed writing it! It was great to find out I could remove that global struct. :) > > Reviewed-by: Kees Cook <keescook@chromium.org> > Thanks! -- Gustavo
Hello: This patch was applied to bluetooth/bluetooth-next.git (master) by Luiz Augusto von Dentz <luiz.von.dentz@intel.com>: On Thu, 2 May 2024 10:22:00 -0600 you wrote: > 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. > > [...] Here is the summary with links: - [next] Bluetooth: hci_conn: Use __counted_by() and avoid -Wfamnae warning https://git.kernel.org/bluetooth/bluetooth-next/c/6d18d5b03ee1 You are awesome, thank you!
diff --git a/include/net/bluetooth/hci.h b/include/net/bluetooth/hci.h index c4c6b8810701..e6838321f4d9 100644 --- a/include/net/bluetooth/hci.h +++ b/include/net/bluetooth/hci.h @@ -2144,7 +2144,7 @@ struct hci_cp_le_set_cig_params { __le16 c_latency; __le16 p_latency; __u8 num_cis; - struct hci_cis_params cis[]; + struct hci_cis_params cis[] __counted_by(num_cis); } __packed; struct hci_rp_le_set_cig_params { diff --git a/net/bluetooth/hci_conn.c b/net/bluetooth/hci_conn.c index c508609be105..6e60e8287956 100644 --- a/net/bluetooth/hci_conn.c +++ b/net/bluetooth/hci_conn.c @@ -665,11 +665,6 @@ static void le_conn_timeout(struct work_struct *work) hci_abort_conn(conn, HCI_ERROR_REMOTE_USER_TERM); } -struct iso_cig_params { - struct hci_cp_le_set_cig_params cp; - struct hci_cis_params cis[0x1f]; -}; - struct iso_list_data { union { u8 cig; @@ -1725,34 +1720,33 @@ static int hci_le_create_big(struct hci_conn *conn, struct bt_iso_qos *qos) static int set_cig_params_sync(struct hci_dev *hdev, void *data) { + DEFINE_FLEX(struct hci_cp_le_set_cig_params, pdu, cis, num_cis, 0x1f); u8 cig_id = PTR_UINT(data); struct hci_conn *conn; struct bt_iso_qos *qos; - struct iso_cig_params pdu; + u8 aux_num_cis = 0; u8 cis_id; conn = hci_conn_hash_lookup_cig(hdev, cig_id); if (!conn) return 0; - memset(&pdu, 0, sizeof(pdu)); - qos = &conn->iso_qos; - pdu.cp.cig_id = cig_id; - hci_cpu_to_le24(qos->ucast.out.interval, pdu.cp.c_interval); - hci_cpu_to_le24(qos->ucast.in.interval, pdu.cp.p_interval); - pdu.cp.sca = qos->ucast.sca; - pdu.cp.packing = qos->ucast.packing; - pdu.cp.framing = qos->ucast.framing; - pdu.cp.c_latency = cpu_to_le16(qos->ucast.out.latency); - pdu.cp.p_latency = cpu_to_le16(qos->ucast.in.latency); + pdu->cig_id = cig_id; + hci_cpu_to_le24(qos->ucast.out.interval, pdu->c_interval); + hci_cpu_to_le24(qos->ucast.in.interval, pdu->p_interval); + pdu->sca = qos->ucast.sca; + pdu->packing = qos->ucast.packing; + pdu->framing = qos->ucast.framing; + pdu->c_latency = cpu_to_le16(qos->ucast.out.latency); + pdu->p_latency = cpu_to_le16(qos->ucast.in.latency); /* Reprogram all CIS(s) with the same CIG, valid range are: * num_cis: 0x00 to 0x1F * cis_id: 0x00 to 0xEF */ for (cis_id = 0x00; cis_id < 0xf0 && - pdu.cp.num_cis < ARRAY_SIZE(pdu.cis); cis_id++) { + aux_num_cis < pdu->num_cis; cis_id++) { struct hci_cis_params *cis; conn = hci_conn_hash_lookup_cis(hdev, NULL, 0, cig_id, cis_id); @@ -1761,7 +1755,7 @@ static int set_cig_params_sync(struct hci_dev *hdev, void *data) qos = &conn->iso_qos; - cis = &pdu.cis[pdu.cp.num_cis++]; + cis = &pdu->cis[aux_num_cis++]; cis->cis_id = cis_id; cis->c_sdu = cpu_to_le16(conn->iso_qos.ucast.out.sdu); cis->p_sdu = cpu_to_le16(conn->iso_qos.ucast.in.sdu); @@ -1772,14 +1766,14 @@ static int set_cig_params_sync(struct hci_dev *hdev, void *data) cis->c_rtn = qos->ucast.out.rtn; cis->p_rtn = qos->ucast.in.rtn; } + pdu->num_cis = aux_num_cis; - if (!pdu.cp.num_cis) + if (!pdu->num_cis) return 0; return __hci_cmd_sync_status(hdev, HCI_OP_LE_SET_CIG_PARAMS, - sizeof(pdu.cp) + - pdu.cp.num_cis * sizeof(pdu.cis[0]), &pdu, - HCI_CMD_TIMEOUT); + struct_size(pdu, cis, pdu->num_cis), + pdu, HCI_CMD_TIMEOUT); } static bool hci_le_set_cig_params(struct hci_conn *conn, struct bt_iso_qos *qos)
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 an on-stack definition 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. With these changes, fix the following warning: net/bluetooth/hci_conn.c:669:41: 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> --- include/net/bluetooth/hci.h | 2 +- net/bluetooth/hci_conn.c | 38 ++++++++++++++++--------------------- 2 files changed, 17 insertions(+), 23 deletions(-)