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| author | Antti Palosaari <crope@iki.fi> | 2009-09-13 02:46:30 +0300 |
|---|---|---|
| committer | Antti Palosaari <crope@iki.fi> | 2009-09-13 02:46:30 +0300 |
| commit | f919ed55d0ece48afb66100dce56494c346879c5 (patch) | |
| tree | 2d5a7a9c910445df096188452754be4412102f41 /linux/drivers/media/dvb/dvb-usb | |
| parent | ff680464a0d27db7be8755753e6b52bfa03d0035 (diff) | |
| download | mediapointer-dvb-s2-f919ed55d0ece48afb66100dce56494c346879c5.tar.gz mediapointer-dvb-s2-f919ed55d0ece48afb66100dce56494c346879c5.tar.bz2 | |
af9015: improve usb control message function slightly
From: Antti Palosaari <crope@iki.fi>
* define names for few values
* decrease buffer len by one byte which was not used
* add check for buffer overflow for sure
* indentation fixes
* remove useless 0 len check from memcpy
It should not happen and if it happens memcpy should not do anything.
Priority: normal
Signed-off-by: Antti Palosaari <crope@iki.fi>
Diffstat (limited to 'linux/drivers/media/dvb/dvb-usb')
| -rw-r--r-- | linux/drivers/media/dvb/dvb-usb/af9015.c | 34 |
1 files changed, 25 insertions, 9 deletions
diff --git a/linux/drivers/media/dvb/dvb-usb/af9015.c b/linux/drivers/media/dvb/dvb-usb/af9015.c index 723253c59..44eb7e46f 100644 --- a/linux/drivers/media/dvb/dvb-usb/af9015.c +++ b/linux/drivers/media/dvb/dvb-usb/af9015.c @@ -61,10 +61,13 @@ static struct af9013_config af9015_af9013_config[] = { static int af9015_rw_udev(struct usb_device *udev, struct req_t *req) { +#define BUF_LEN 63 +#define REQ_HDR_LEN 8 /* send header size */ +#define ACK_HDR_LEN 2 /* rece header size */ int act_len, ret; - u8 buf[64]; + u8 buf[BUF_LEN]; u8 write = 1; - u8 msg_len = 8; + u8 msg_len = REQ_HDR_LEN; static u8 seq; /* packet sequence number */ if (mutex_lock_interruptible(&af9015_usb_mutex) < 0) @@ -107,17 +110,26 @@ static int af9015_rw_udev(struct usb_device *udev, struct req_t *req) goto error_unlock; } + /* buffer overflow check */ + if ((write && (req->data_len > BUF_LEN - REQ_HDR_LEN)) || + (!write && (req->data_len > BUF_LEN - ACK_HDR_LEN))) { + err("too much data; cmd:%d len:%d", req->cmd, req->data_len); + ret = -EINVAL; + goto error_unlock; + } + /* write requested */ - if (write && req->data_len) { - memcpy(&buf[8], req->data, req->data_len); + if (write) { + memcpy(&buf[REQ_HDR_LEN], req->data, req->data_len); msg_len += req->data_len; } + deb_xfer(">>> "); debug_dump(buf, msg_len, deb_xfer); /* send req */ ret = usb_bulk_msg(udev, usb_sndbulkpipe(udev, 0x02), buf, msg_len, - &act_len, AF9015_USB_TIMEOUT); + &act_len, AF9015_USB_TIMEOUT); if (ret) err("bulk message failed:%d (%d/%d)", ret, msg_len, act_len); else @@ -130,10 +142,14 @@ static int af9015_rw_udev(struct usb_device *udev, struct req_t *req) if (req->cmd == DOWNLOAD_FIRMWARE || req->cmd == RECONNECT_USB) goto exit_unlock; - /* receive ack and data if read req */ - msg_len = 1 + 1 + req->data_len; /* seq + status + data len */ + /* write receives seq + status = 2 bytes + read receives seq + status + data = 2 + N bytes */ + msg_len = ACK_HDR_LEN; + if (!write) + msg_len += req->data_len; + ret = usb_bulk_msg(udev, usb_rcvbulkpipe(udev, 0x81), buf, msg_len, - &act_len, AF9015_USB_TIMEOUT); + &act_len, AF9015_USB_TIMEOUT); if (ret) { err("recv bulk message failed:%d", ret); ret = -1; @@ -159,7 +175,7 @@ static int af9015_rw_udev(struct usb_device *udev, struct req_t *req) /* read request, copy returned data to return buf */ if (!write) - memcpy(req->data, &buf[2], req->data_len); + memcpy(req->data, &buf[ACK_HDR_LEN], req->data_len); error_unlock: exit_unlock: |