4.18-stable review patch. If anyone has any objections, please let me know.
------------------
From: H. Peter Anvin <h...@zytor.com>
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) <h...@zytor.com>
Requested-by: Cc: Johan Hovold <jo...@kernel.org>
Cc: Jiri Slaby <jsl...@suse.com>
Cc: Al Viro <v...@zeniv.linux.org.uk>
Cc: Richard Henderson <r...@twiddle.net>
Cc: Ivan Kokshaysky <i...@jurassic.park.msu.ru>
Cc: Matt Turner <matts...@gmail.com>
Cc: Thomas Gleixner <t...@linutronix.de>
Cc: Kate Stewart <kstew...@linuxfoundation.org>
Cc: Philippe Ombredanne <pombreda...@nexb.com>
Cc: Eugene Syromiatnikov <e...@redhat.com>
Cc: Alan Cox <a...@lxorguk.ukuu.org.uk>
Cc: stable <sta...@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gre...@linuxfoundation.org>
---
drivers/tty/tty_baudrate.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
--- a/drivers/tty/tty_baudrate.c
+++ b/drivers/tty/tty_baudrate.c
@@ -77,7 +77,7 @@ speed_t tty_termios_baud_rate(struct kte
else
cbaud += 15;
}
- return baud_table[cbaud];
+ return cbaud >= n_baud_table ? 0 : baud_table[cbaud];
}
EXPORT_SYMBOL(tty_termios_baud_rate);
@@ -113,7 +113,7 @@ speed_t tty_termios_input_baud_rate(stru
else
cbaud += 15;
}
- return baud_table[cbaud];
+ return cbaud >= n_baud_table ? 0 : baud_table[cbaud];
#else
return tty_termios_baud_rate(termios);
#endif
