[PATCH] Potential null pointer dereference in amiga serial driver
A pointer is dereferenced before it is null-checked.
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/drivers/char/amiserial.c b/drivers/char/amiserial.c
index 1dc4259..777bc49 100644
--- a/drivers/char/amiserial.c
+++ b/drivers/char/amiserial.c
@@ -861,13 +861,18 @@
static void rs_put_char(struct tty_struct *tty, unsigned char ch)
{
- struct async_struct *info = (struct async_struct *)tty->driver_data;
+ struct async_struct *info;
unsigned long flags;
+ if (!tty)
+ return;
+
+ info = tty->driver_data;
+
if (serial_paranoia_check(info, tty->name, "rs_put_char"))
return;
- if (!tty || !info->xmit.buf)
+ if (!info->xmit.buf)
return;
local_irq_save(flags);
@@ -910,13 +915,18 @@
static int rs_write(struct tty_struct * tty, const unsigned char *buf, int count)
{
int c, ret = 0;
- struct async_struct *info = (struct async_struct *)tty->driver_data;
+ struct async_struct *info;
unsigned long flags;
+ if (!tty)
+ return 0;
+
+ info = tty->driver_data;
+
if (serial_paranoia_check(info, tty->name, "rs_write"))
return 0;
- if (!tty || !info->xmit.buf || !tmp_buf)
+ if (!info->xmit.buf || !tmp_buf)
return 0;
local_save_flags(flags);