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author | Jiri Slaby <jslaby@suse.cz> | 2011-02-28 10:34:05 +0100 |
---|---|---|
committer | Greg Kroah-Hartman <gregkh@suse.de> | 2011-02-28 19:24:54 -0800 |
commit | f7d7aedfcd4e20e7dfc7356d30cc22dc0b0f493e (patch) | |
tree | 69b2b977e5900de9e5a5a2b934ecadc7b0ccbf33 /drivers/usb/serial/keyspan_pda.c | |
parent | 7adc14b14b43b6ca9f2f00ac7a4780577dbe883b (diff) | |
download | op-kernel-dev-f7d7aedfcd4e20e7dfc7356d30cc22dc0b0f493e.zip op-kernel-dev-f7d7aedfcd4e20e7dfc7356d30cc22dc0b0f493e.tar.gz |
USB: serial/keyspan_pda, fix potential tty NULL dereferences
Make sure that we check the return value of tty_port_tty_get.
Sometimes it may return NULL and we later dereference that.
There are several places to check. For easier handling,
tty_port_tty_get is moved directly to the palce where needed in
keyspan_pda_rx_interrupt.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Diffstat (limited to 'drivers/usb/serial/keyspan_pda.c')
-rw-r--r-- | drivers/usb/serial/keyspan_pda.c | 15 |
1 files changed, 8 insertions, 7 deletions
diff --git a/drivers/usb/serial/keyspan_pda.c b/drivers/usb/serial/keyspan_pda.c index 554a869..7b690f3 100644 --- a/drivers/usb/serial/keyspan_pda.c +++ b/drivers/usb/serial/keyspan_pda.c @@ -173,7 +173,8 @@ static void keyspan_pda_wakeup_write(struct work_struct *work) container_of(work, struct keyspan_pda_private, wakeup_work); struct usb_serial_port *port = priv->port; struct tty_struct *tty = tty_port_tty_get(&port->port); - tty_wakeup(tty); + if (tty) + tty_wakeup(tty); tty_kref_put(tty); } @@ -206,7 +207,7 @@ static void keyspan_pda_request_unthrottle(struct work_struct *work) static void keyspan_pda_rx_interrupt(struct urb *urb) { struct usb_serial_port *port = urb->context; - struct tty_struct *tty = tty_port_tty_get(&port->port); + struct tty_struct *tty; unsigned char *data = urb->transfer_buffer; int retval; int status = urb->status; @@ -223,7 +224,7 @@ static void keyspan_pda_rx_interrupt(struct urb *urb) /* this urb is terminated, clean up */ dbg("%s - urb shutting down with status: %d", __func__, status); - goto out; + return; default: dbg("%s - nonzero urb status received: %d", __func__, status); @@ -233,12 +234,14 @@ static void keyspan_pda_rx_interrupt(struct urb *urb) /* see if the message is data or a status interrupt */ switch (data[0]) { case 0: - /* rest of message is rx data */ - if (urb->actual_length) { + tty = tty_port_tty_get(&port->port); + /* rest of message is rx data */ + if (tty && urb->actual_length) { tty_insert_flip_string(tty, data + 1, urb->actual_length - 1); tty_flip_buffer_push(tty); } + tty_kref_put(tty); break; case 1: /* status interrupt */ @@ -265,8 +268,6 @@ exit: dev_err(&port->dev, "%s - usb_submit_urb failed with result %d", __func__, retval); -out: - tty_kref_put(tty); } |