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| author | Elina Pasheva <epasheva@sierrawireless.com> | 2010-02-15 14:50:14 -0800 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@suse.de> | 2010-03-02 14:55:03 -0800 |
| commit | b87c6e86dac1bb5222279cc8ff7e09529e1c4ed9 (patch) | |
| tree | 01c52edb21677004ad1a64c20f1f3f965ee13b27 /drivers/usb/serial | |
| parent | 7650cd9678df29b01d1e46a9d2ce7e5d8c72b3ce (diff) | |
| download | lwn-b87c6e86dac1bb5222279cc8ff7e09529e1c4ed9.tar.gz lwn-b87c6e86dac1bb5222279cc8ff7e09529e1c4ed9.zip | |
USB: serial: sierra driver indat_callback fix
A crash has been reported with sierra driver on disconnect with
Ubuntu/Lucid distribution based on kernel-2.6.32.
The cause of the crash was determined as "NULL tty pointer was being
referenced" and the NULL pointer was passed by sierra_indat_callback().
This patch modifies sierra_indat_callback() function to check for NULL
tty structure pointer. This modification prevents a crash from happening
when the device is disconnected.
This patch fixes the bug reported in Launchpad:
https://bugs.launchpad.net/ubuntu/+source/linux/+bug/511157
Signed-off-by: Elina Pasheva <epasheva@sierrawireless.com>
Cc: stable <stable@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Diffstat (limited to 'drivers/usb/serial')
| -rw-r--r-- | drivers/usb/serial/sierra.c | 19 |
1 files changed, 11 insertions, 8 deletions
diff --git a/drivers/usb/serial/sierra.c b/drivers/usb/serial/sierra.c index 6aeea40081c2..fcec46603558 100644 --- a/drivers/usb/serial/sierra.c +++ b/drivers/usb/serial/sierra.c @@ -594,14 +594,17 @@ static void sierra_indat_callback(struct urb *urb) } else { if (urb->actual_length) { tty = tty_port_tty_get(&port->port); - - tty_buffer_request_room(tty, urb->actual_length); - tty_insert_flip_string(tty, data, urb->actual_length); - tty_flip_buffer_push(tty); - - tty_kref_put(tty); - usb_serial_debug_data(debug, &port->dev, __func__, - urb->actual_length, data); + if (tty) { + tty_buffer_request_room(tty, + urb->actual_length); + tty_insert_flip_string(tty, data, + urb->actual_length); + tty_flip_buffer_push(tty); + + tty_kref_put(tty); + usb_serial_debug_data(debug, &port->dev, + __func__, urb->actual_length, data); + } } else { dev_dbg(&port->dev, "%s: empty read urb" " received\n", __func__); |