From 9616ff434d96303689391af3d6e1c845d233405f Mon Sep 17 00:00:00 2001 From: "David S. Miller" Date: Wed, 26 May 2010 21:17:29 -0700 Subject: [PATCH] sunsu: Fix use after free in su_remove(). Real serial port 'up' objects are statically allocated from an array in the driver. Keyboard and mouse ports, on the other hand, are dynamically allocated. Unfortunately, we free these dynamic 'up' objects before we unmap the I/O registers. Rearrange su_remove() so that this does not happen. Noticed by Julia Lawall. Signed-off-by: David S. Miller --- drivers/serial/sunsu.c | 13 +++++++++---- 1 file changed, 9 insertions(+), 4 deletions(-) diff --git a/drivers/serial/sunsu.c b/drivers/serial/sunsu.c index 234459c2f012..ffbf4553f665 100644 --- a/drivers/serial/sunsu.c +++ b/drivers/serial/sunsu.c @@ -1500,20 +1500,25 @@ out_unmap: static int __devexit su_remove(struct of_device *op) { struct uart_sunsu_port *up = dev_get_drvdata(&op->dev); + bool kbdms = false; if (up->su_type == SU_PORT_MS || - up->su_type == SU_PORT_KBD) { + up->su_type == SU_PORT_KBD) + kbdms = true; + + if (kbdms) { #ifdef CONFIG_SERIO serio_unregister_port(&up->serio); #endif - kfree(up); - } else if (up->port.type != PORT_UNKNOWN) { + } else if (up->port.type != PORT_UNKNOWN) uart_remove_one_port(&sunsu_reg, &up->port); - } if (up->port.membase) of_iounmap(&op->resource[0], up->port.membase, up->reg_size); + if (kbdms) + kfree(up); + dev_set_drvdata(&op->dev, NULL); return 0; -- 2.34.1