Commit 542f25a9 authored by Paulo Miguel Almeida's avatar Paulo Miguel Almeida Committed by Jiri Kosina
Browse files

HID: hyperv: Replace one-element array with flexible-array member 

One-element arrays are deprecated, and we are replacing them with
flexible array members instead. So, replace one-element array with
flexible-array member in structs synthhid_msg, synthhid_input_report,
pipe_prt_msg and refactor the rest of the code accordingly.

This helps with the ongoing efforts to tighten the FORTIFY_SOURCE
routines on memcpy() and help us make progress towards globally
enabling -fstrict-flex-arrays=3 [1].

Link: https://github.com/KSPP/linux/issues/79
Link: https://github.com/KSPP/linux/issues/210
Link: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=101836

 [1]

Signed-off-by: default avatarPaulo Miguel Almeida <paulo.miguel.almeida.rodenas@gmail.com>
Reviewed-by: default avatarBenjamin Tissoires <benjamin.tissoires@redhat.com>
Reviewed-by: default avatarMichael Kelley <mikelley@microsoft.com>
Signed-off-by: default avatarJiri Kosina <jkosina@suse.cz>
parent 79d11de9

drivers/hid/hid-hyperv.c

+7 −10
Original line number Diff line number Diff line
@@ -61,7 +61,7 @@ struct synthhid_msg_hdr { 


struct synthhid_msg {

	struct synthhid_msg_hdr header;

	char data[1]; /* Enclosed message */

	char data[]; /* Enclosed message */

};



union synthhid_version {
@@ -99,7 +99,7 @@ struct synthhid_device_info_ack { 


struct synthhid_input_report {

	struct synthhid_msg_hdr header;

	char buffer[1];

	char buffer[];

};



#pragma pack(pop)
@@ -118,7 +118,7 @@ enum pipe_prot_msg_type { 
struct pipe_prt_msg {

	enum pipe_prot_msg_type type;

	u32 size;

	char data[1];

	char data[];

};



struct  mousevsc_prt_msg {
@@ -232,7 +232,7 @@ static void mousevsc_on_receive_device_info(struct mousevsc_dev *input_device, 


	ret = vmbus_sendpacket(input_device->device->channel,

			&ack,

			sizeof(struct pipe_prt_msg) - sizeof(unsigned char) +

			sizeof(struct pipe_prt_msg) +

			sizeof(struct synthhid_device_info_ack),

			(unsigned long)&ack,

			VM_PKT_DATA_INBAND,
@@ -271,16 +271,14 @@ static void mousevsc_on_receive(struct hv_device *device, 
		 * malicious/buggy hypervisor/host, add a check here to

		 * ensure we don't corrupt memory.

		 */

		if ((pipe_msg->size + sizeof(struct pipe_prt_msg)

			- sizeof(unsigned char))

		if (struct_size(pipe_msg, data, pipe_msg->size)

			> sizeof(struct mousevsc_prt_msg)) {

			WARN_ON(1);

			break;

		}



		memcpy(&input_dev->protocol_resp, pipe_msg,

		       pipe_msg->size + sizeof(struct pipe_prt_msg) -

		       sizeof(unsigned char));

				struct_size(pipe_msg, data, pipe_msg->size));

		complete(&input_dev->wait_event);

		break;
@@ -359,8 +357,7 @@ static int mousevsc_connect_to_vsp(struct hv_device *device) 
	request->request.version_requested.version = SYNTHHID_INPUT_VERSION;



	ret = vmbus_sendpacket(device->channel, request,

				sizeof(struct pipe_prt_msg) -

				sizeof(unsigned char) +

				sizeof(struct pipe_prt_msg) +

				sizeof(struct synthhid_protocol_request),

				(unsigned long)request,

				VM_PKT_DATA_INBAND,