From a7e454542bf8d57c75f59e7e7326c21db3d0bb3f Mon Sep 17 00:00:00 2001 From: "Gustavo A. R. Silva" Date: Wed, 26 Feb 2020 17:02:27 -0600 Subject: [PATCH] Bluetooth: Replace zero-length array with flexible-array member The current codebase makes use of the zero-length array language extension to the C90 standard, but the preferred mechanism to declare variable-length types such as these ones is a flexible array member[1][2], introduced in C99: struct foo { int stuff; struct boo array[]; }; By making use of the mechanism above, we will get a compiler warning in case the flexible array does not occur last in the structure, which will help us prevent some kind of undefined behavior bugs from being inadvertently introduced[3] to the codebase from now on. Also, notice that, dynamic memory allocations won't be affected by this change: "Flexible array members have incomplete type, and so the sizeof operator may not be applied. As a quirk of the original implementation of zero-length arrays, sizeof evaluates to zero."[1] This issue was found with the help of Coccinelle. [1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html [2] https://github.com/KSPP/linux/issues/21 [3] commit 76497732932f ("cxgb3/l2t: Fix undefined behaviour") Signed-off-by: Gustavo A. R. Silva Signed-off-by: Marcel Holtmann --- drivers/bluetooth/btqca.h | 6 +++--- drivers/bluetooth/btrtl.h | 4 ++-- include/net/bluetooth/hci.h | 30 +++++++++++++++--------------- include/net/bluetooth/hci_sock.h | 6 +++--- include/net/bluetooth/l2cap.h | 8 ++++---- include/net/bluetooth/rfcomm.h | 2 +- net/bluetooth/a2mp.h | 10 +++++----- net/bluetooth/bnep/bnep.h | 6 +++--- 8 files changed, 36 insertions(+), 36 deletions(-) diff --git a/drivers/bluetooth/btqca.h b/drivers/bluetooth/btqca.h index f5795b1a3779..e16a4d650597 100644 --- a/drivers/bluetooth/btqca.h +++ b/drivers/bluetooth/btqca.h @@ -79,7 +79,7 @@ struct qca_fw_config { struct edl_event_hdr { __u8 cresp; __u8 rtype; - __u8 data[0]; + __u8 data[]; } __packed; struct qca_btsoc_version { @@ -112,12 +112,12 @@ struct tlv_type_nvm { __le16 tag_len; __le32 reserve1; __le32 reserve2; - __u8 data[0]; + __u8 data[]; } __packed; struct tlv_type_hdr { __le32 type_len; - __u8 data[0]; + __u8 data[]; } __packed; enum qca_btsoc_type { diff --git a/drivers/bluetooth/btrtl.h b/drivers/bluetooth/btrtl.h index 10ad40c3e42c..2a582682136d 100644 --- a/drivers/bluetooth/btrtl.h +++ b/drivers/bluetooth/btrtl.h @@ -38,13 +38,13 @@ struct rtl_epatch_header { struct rtl_vendor_config_entry { __le16 offset; __u8 len; - __u8 data[0]; + __u8 data[]; } __packed; struct rtl_vendor_config { __le32 signature; __le16 total_len; - struct rtl_vendor_config_entry entry[0]; + struct rtl_vendor_config_entry entry[]; } __packed; #if IS_ENABLED(CONFIG_BT_RTL) diff --git a/include/net/bluetooth/hci.h b/include/net/bluetooth/hci.h index 6293bdd7d862..d878bf8dce20 100644 --- a/include/net/bluetooth/hci.h +++ b/include/net/bluetooth/hci.h @@ -935,7 +935,7 @@ struct hci_cp_sniff_subrate { struct hci_cp_set_event_flt { __u8 flt_type; __u8 cond_type; - __u8 condition[0]; + __u8 condition[]; } __packed; /* Filter types */ @@ -1335,7 +1335,7 @@ struct hci_rp_read_local_amp_assoc { __u8 status; __u8 phy_handle; __le16 rem_len; - __u8 frag[0]; + __u8 frag[]; } __packed; #define HCI_OP_WRITE_REMOTE_AMP_ASSOC 0x140b @@ -1343,7 +1343,7 @@ struct hci_cp_write_remote_amp_assoc { __u8 phy_handle; __le16 len_so_far; __le16 rem_len; - __u8 frag[0]; + __u8 frag[]; } __packed; struct hci_rp_write_remote_amp_assoc { __u8 status; @@ -1613,7 +1613,7 @@ struct hci_cp_le_set_ext_scan_params { __u8 own_addr_type; __u8 filter_policy; __u8 scanning_phys; - __u8 data[0]; + __u8 data[]; } __packed; #define LE_SCAN_PHY_1M 0x01 @@ -1641,7 +1641,7 @@ struct hci_cp_le_ext_create_conn { __u8 peer_addr_type; bdaddr_t peer_addr; __u8 phys; - __u8 data[0]; + __u8 data[]; } __packed; struct hci_cp_le_ext_conn_param { @@ -1693,7 +1693,7 @@ struct hci_rp_le_set_ext_adv_params { struct hci_cp_le_set_ext_adv_enable { __u8 enable; __u8 num_of_sets; - __u8 data[0]; + __u8 data[]; } __packed; struct hci_cp_ext_adv_set { @@ -1775,14 +1775,14 @@ struct hci_cp_le_set_cig_params { __le16 m_latency; __le16 s_latency; __u8 num_cis; - struct hci_cis_params cis[0]; + struct hci_cis_params cis[]; } __packed; struct hci_rp_le_set_cig_params { __u8 status; __u8 cig_id; __u8 num_handles; - __le16 handle[0]; + __le16 handle[]; } __packed; #define HCI_OP_LE_CREATE_CIS 0x2064 @@ -1793,7 +1793,7 @@ struct hci_cis { struct hci_cp_le_create_cis { __u8 num_cis; - struct hci_cis cis[0]; + struct hci_cis cis[]; } __packed; #define HCI_OP_LE_REMOVE_CIG 0x2065 @@ -1937,7 +1937,7 @@ struct hci_comp_pkts_info { struct hci_ev_num_comp_pkts { __u8 num_hndl; - struct hci_comp_pkts_info handles[0]; + struct hci_comp_pkts_info handles[]; } __packed; #define HCI_EV_MODE_CHANGE 0x14 @@ -2170,7 +2170,7 @@ struct hci_comp_blocks_info { struct hci_ev_num_comp_blocks { __le16 num_blocks; __u8 num_hndl; - struct hci_comp_blocks_info handles[0]; + struct hci_comp_blocks_info handles[]; } __packed; #define HCI_EV_SYNC_TRAIN_COMPLETE 0x4F @@ -2226,7 +2226,7 @@ struct hci_ev_le_advertising_info { __u8 bdaddr_type; bdaddr_t bdaddr; __u8 length; - __u8 data[0]; + __u8 data[]; } __packed; #define HCI_EV_LE_CONN_UPDATE_COMPLETE 0x03 @@ -2302,7 +2302,7 @@ struct hci_ev_le_ext_adv_report { __u8 direct_addr_type; bdaddr_t direct_addr; __u8 length; - __u8 data[0]; + __u8 data[]; } __packed; #define HCI_EV_LE_ENHANCED_CONN_COMPLETE 0x0a @@ -2362,7 +2362,7 @@ struct hci_evt_le_cis_req { #define HCI_EV_STACK_INTERNAL 0xfd struct hci_ev_stack_internal { __u16 type; - __u8 data[0]; + __u8 data[]; } __packed; #define HCI_EV_SI_DEVICE 0x01 @@ -2409,7 +2409,7 @@ struct hci_sco_hdr { struct hci_iso_hdr { __le16 handle; __le16 dlen; - __u8 data[0]; + __u8 data[]; } __packed; /* ISO data packet status flags */ diff --git a/include/net/bluetooth/hci_sock.h b/include/net/bluetooth/hci_sock.h index 8e9138acdae1..9352bb1bf34c 100644 --- a/include/net/bluetooth/hci_sock.h +++ b/include/net/bluetooth/hci_sock.h @@ -144,19 +144,19 @@ struct hci_dev_req { struct hci_dev_list_req { __u16 dev_num; - struct hci_dev_req dev_req[0]; /* hci_dev_req structures */ + struct hci_dev_req dev_req[]; /* hci_dev_req structures */ }; struct hci_conn_list_req { __u16 dev_id; __u16 conn_num; - struct hci_conn_info conn_info[0]; + struct hci_conn_info conn_info[]; }; struct hci_conn_info_req { bdaddr_t bdaddr; __u8 type; - struct hci_conn_info conn_info[0]; + struct hci_conn_info conn_info[]; }; struct hci_auth_info_req { diff --git a/include/net/bluetooth/l2cap.h b/include/net/bluetooth/l2cap.h index 093aedebdf0c..61dc731d5666 100644 --- a/include/net/bluetooth/l2cap.h +++ b/include/net/bluetooth/l2cap.h @@ -299,14 +299,14 @@ struct l2cap_conn_rsp { struct l2cap_conf_req { __le16 dcid; __le16 flags; - __u8 data[0]; + __u8 data[]; } __packed; struct l2cap_conf_rsp { __le16 scid; __le16 flags; __le16 result; - __u8 data[0]; + __u8 data[]; } __packed; #define L2CAP_CONF_SUCCESS 0x0000 @@ -322,7 +322,7 @@ struct l2cap_conf_rsp { struct l2cap_conf_opt { __u8 type; __u8 len; - __u8 val[0]; + __u8 val[]; } __packed; #define L2CAP_CONF_OPT_SIZE 2 @@ -392,7 +392,7 @@ struct l2cap_info_req { struct l2cap_info_rsp { __le16 type; __le16 result; - __u8 data[0]; + __u8 data[]; } __packed; struct l2cap_create_chan_req { diff --git a/include/net/bluetooth/rfcomm.h b/include/net/bluetooth/rfcomm.h index 8d65d2a0b9b4..99d26879b02a 100644 --- a/include/net/bluetooth/rfcomm.h +++ b/include/net/bluetooth/rfcomm.h @@ -355,7 +355,7 @@ struct rfcomm_dev_info { struct rfcomm_dev_list_req { u16 dev_num; - struct rfcomm_dev_info dev_info[0]; + struct rfcomm_dev_info dev_info[]; }; int rfcomm_dev_ioctl(struct sock *sk, unsigned int cmd, void __user *arg); diff --git a/net/bluetooth/a2mp.h b/net/bluetooth/a2mp.h index 0029d5119be6..2fd253a61a2a 100644 --- a/net/bluetooth/a2mp.h +++ b/net/bluetooth/a2mp.h @@ -36,14 +36,14 @@ struct a2mp_cmd { __u8 code; __u8 ident; __le16 len; - __u8 data[0]; + __u8 data[]; } __packed; /* A2MP command codes */ #define A2MP_COMMAND_REJ 0x01 struct a2mp_cmd_rej { __le16 reason; - __u8 data[0]; + __u8 data[]; } __packed; #define A2MP_DISCOVER_REQ 0x02 @@ -62,7 +62,7 @@ struct a2mp_cl { struct a2mp_discov_rsp { __le16 mtu; __le16 ext_feat; - struct a2mp_cl cl[0]; + struct a2mp_cl cl[]; } __packed; #define A2MP_CHANGE_NOTIFY 0x04 @@ -93,7 +93,7 @@ struct a2mp_amp_assoc_req { struct a2mp_amp_assoc_rsp { __u8 id; __u8 status; - __u8 amp_assoc[0]; + __u8 amp_assoc[]; } __packed; #define A2MP_CREATEPHYSLINK_REQ 0x0A @@ -101,7 +101,7 @@ struct a2mp_amp_assoc_rsp { struct a2mp_physlink_req { __u8 local_id; __u8 remote_id; - __u8 amp_assoc[0]; + __u8 amp_assoc[]; } __packed; #define A2MP_CREATEPHYSLINK_RSP 0x0B diff --git a/net/bluetooth/bnep/bnep.h b/net/bluetooth/bnep/bnep.h index 24f18b133959..9680473ed7ef 100644 --- a/net/bluetooth/bnep/bnep.h +++ b/net/bluetooth/bnep/bnep.h @@ -74,14 +74,14 @@ struct bnep_setup_conn_req { __u8 type; __u8 ctrl; __u8 uuid_size; - __u8 service[0]; + __u8 service[]; } __packed; struct bnep_set_filter_req { __u8 type; __u8 ctrl; __be16 len; - __u8 list[0]; + __u8 list[]; } __packed; struct bnep_control_rsp { @@ -93,7 +93,7 @@ struct bnep_control_rsp { struct bnep_ext_hdr { __u8 type; __u8 len; - __u8 data[0]; + __u8 data[]; } __packed; /* BNEP ioctl defines */