From 9742f5458d330a758b33a4aabd7c58fd378f145f Mon Sep 17 00:00:00 2001 From: Johan Hovold Date: Thu, 12 Jan 2017 14:56:14 +0100 Subject: [PATCH] USB: serial: io_edgeport: fix descriptor error handling commit 3c0e25d883d06a1fbd1ad35257e8abaa57befb37 upstream. Make sure to detect short control-message transfers and log an error when reading incomplete manufacturer and boot descriptors. Note that the default all-zero descriptors will now be used after a short transfer is detected instead of partially initialised ones. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Reviewed-by: Greg Kroah-Hartman Signed-off-by: Johan Hovold [bwh: Backported to 3.2: adjust context] Signed-off-by: Ben Hutchings --- drivers/usb/serial/io_edgeport.c | 24 +++++++++++++++--------- 1 file changed, 15 insertions(+), 9 deletions(-) diff --git a/drivers/usb/serial/io_edgeport.c b/drivers/usb/serial/io_edgeport.c index e5795c0b410c..d4109f221e1e 100644 --- a/drivers/usb/serial/io_edgeport.c +++ b/drivers/usb/serial/io_edgeport.c @@ -2263,8 +2263,7 @@ static int rom_write(struct usb_serial *serial, __u16 extAddr, __u16 addr, * rom_read * reads a number of bytes from the Edgeport device starting at the given * address. - * If successful returns the number of bytes read, otherwise it returns - * a negative error number of the problem. + * Returns zero on success or a negative error number. ****************************************************************************/ static int rom_read(struct usb_serial *serial, __u16 extAddr, __u16 addr, __u16 length, __u8 *data) @@ -2296,12 +2295,17 @@ static int rom_read(struct usb_serial *serial, __u16 extAddr, USB_REQUEST_ION_READ_ROM, 0xC0, addr, extAddr, transfer_buffer, current_length, 300); - if (result < 0) + if (result < current_length) { + if (result >= 0) + result = -EIO; break; + } memcpy(data, transfer_buffer, current_length); length -= current_length; addr += current_length; data += current_length; + + result = 0; } kfree(transfer_buffer); @@ -2772,10 +2776,11 @@ static void get_manufacturing_desc(struct edgeport_serial *edge_serial) EDGE_MANUF_DESC_LEN, (__u8 *)(&edge_serial->manuf_descriptor)); - if (response < 1) + if (response < 0) { dev_err(&edge_serial->serial->dev->dev, - "error in getting manufacturer descriptor\n"); - else { + "error in getting manufacturer descriptor: %d\n", + response); + } else { char string[30]; dbg("**Manufacturer Descriptor"); dbg(" RomSize: %dK", @@ -2831,10 +2836,11 @@ static void get_boot_desc(struct edgeport_serial *edge_serial) EDGE_BOOT_DESC_LEN, (__u8 *)(&edge_serial->boot_descriptor)); - if (response < 1) + if (response < 0) { dev_err(&edge_serial->serial->dev->dev, - "error in getting boot descriptor\n"); - else { + "error in getting boot descriptor: %d\n", + response); + } else { dbg("**Boot Descriptor:"); dbg(" BootCodeLength: %d", le16_to_cpu(edge_serial->boot_descriptor.BootCodeLength)); -- 2.39.2