diff options
author | Dirk Eibach <eibach@gdsys.de> | 2009-06-18 16:49:15 -0700 |
---|---|---|
committer | Greg Kroah-Hartman <gregkh@suse.de> | 2009-07-02 16:31:28 -0700 |
commit | 72f08ac8548b7cfb1f280340f40cc8ae702612b3 (patch) | |
tree | 1829342fc94c597e49970136f75ed5c1b84e0b7f | |
parent | 442427fba55fa4d8c6a53913feb752ecf137984c (diff) |
char: moxa, prevent opening unavailable ports
commit a90b037583d5f1ae3e54e9c687c79df82d1d34a4 upstream.
In moxa.c there are 32 minor numbers reserved for each device. The number
of ports actually available per device is stored in
moxa_board_conf->numPorts. This number is not considered in moxa_open().
Opening a port that is not available results in a kernel oops. This patch
adds a test to moxa_open() that prevents opening unavailable ports.
[akpm@linux-foundation.org: avoid multiple returns]
Signed-off-by: Dirk Eibach <eibach@gdsys.de>
Signed-off-by: Jiri Slaby <jirislaby@gmail.com>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
-rw-r--r-- | drivers/char/moxa.c | 7 |
1 files changed, 6 insertions, 1 deletions
diff --git a/drivers/char/moxa.c b/drivers/char/moxa.c index d3d7864e0c1..729be5ea7b3 100644 --- a/drivers/char/moxa.c +++ b/drivers/char/moxa.c @@ -1158,6 +1158,11 @@ static int moxa_open(struct tty_struct *tty, struct file *filp) return -ENODEV; } + if (port % MAX_PORTS_PER_BOARD >= brd->numPorts) { + retval = -ENODEV; + goto out_unlock; + } + ch = &brd->ports[port % MAX_PORTS_PER_BOARD]; ch->port.count++; tty->driver_data = ch; @@ -1182,8 +1187,8 @@ static int moxa_open(struct tty_struct *tty, struct file *filp) moxa_close_port(ch); } else ch->port.flags |= ASYNC_NORMAL_ACTIVE; +out_unlock: mutex_unlock(&moxa_openlock); - return retval; } |