summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorDirk Eibach <eibach@gdsys.de>2009-06-19 03:49:15 +0400
committerLinus Torvalds <torvalds@linux-foundation.org>2009-06-20 03:46:06 +0400
commita90b037583d5f1ae3e54e9c687c79df82d1d34a4 (patch)
treea399772347bfa16ba9ee76caa9a14105987b8c01
parent0b9ce5a20138590bd9556e34a0408164fadf4163 (diff)
downloadlinux-a90b037583d5f1ae3e54e9c687c79df82d1d34a4.tar.xz
char: moxa, prevent opening unavailable ports
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>
-rw-r--r--drivers/char/moxa.c7
1 files changed, 6 insertions, 1 deletions
diff --git a/drivers/char/moxa.c b/drivers/char/moxa.c
index 65b6ff2442c6..6799588b0099 100644
--- a/drivers/char/moxa.c
+++ b/drivers/char/moxa.c
@@ -1189,6 +1189,11 @@ 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;
@@ -1213,8 +1218,8 @@ static int moxa_open(struct tty_struct *tty, struct file *filp)
moxa_close_port(tty);
} else
ch->port.flags |= ASYNC_NORMAL_ACTIVE;
+out_unlock:
mutex_unlock(&moxa_openlock);
-
return retval;
}