termios, tty/tty_baudrate.c: fix buffer overrun
authorH. Peter Anvin <hpa@zytor.com>
Mon, 22 Oct 2018 16:19:04 +0000 (09:19 -0700)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Wed, 21 Nov 2018 08:24:10 +0000 (09:24 +0100)
commitd85114a0a131e839070728f2d7bc253a9bfa8eb8
tree076902c7b9583252685bdcb954afcb0cf6266509
parentde51aafd80bedac4ce10072510203d67eb6ea3b4
termios, tty/tty_baudrate.c: fix buffer overrun

commit 991a25194097006ec1e0d2e0814ff920e59e3465 upstream.

On architectures with CBAUDEX == 0 (Alpha and PowerPC), the code in tty_baudrate.c does
not do any limit checking on the tty_baudrate[] array, and in fact a
buffer overrun is possible on both architectures. Add a limit check to
prevent that situation.

This will be followed by a much bigger cleanup/simplification patch.

Signed-off-by: H. Peter Anvin (Intel) <hpa@zytor.com>
Requested-by: Cc: Johan Hovold <johan@kernel.org>
Cc: Jiri Slaby <jslaby@suse.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Kate Stewart <kstewart@linuxfoundation.org>
Cc: Philippe Ombredanne <pombredanne@nexb.com>
Cc: Eugene Syromiatnikov <esyr@redhat.com>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
drivers/tty/tty_baudrate.c