[PATCH 109/115] drivers/char/ipmi: memcpy, need additional 2 bytes to avoid memory overflow

[Luis Henriques]

3.5.7.13 -stable review patch.  If anyone has any objections, please let me know.

------------------

From: Chen Gang <gang.chen at asianux.com>

commit a5f2b3d6a738e7d4180012fe7b541172f8c8dcea upstream.

When calling memcpy, read_data and write_data need additional 2 bytes.

  write_data:
    for checking:  "if (size > IPMI_MAX_MSG_LENGTH)"
    for operating: "memcpy(bt->write_data + 3, data + 1, size - 1)"

  read_data:
    for checking:  "if (msg_len < 3 || msg_len > IPMI_MAX_MSG_LENGTH)"
    for operating: "memcpy(data + 2, bt->read_data + 4, msg_len - 2)"

Signed-off-by: Chen Gang <gang.chen at asianux.com>
Signed-off-by: Corey Minyard <cminyard at mvista.com>
Signed-off-by: Linus Torvalds <torvalds at linux-foundation.org>
Signed-off-by: Luis Henriques <luis.henriques at canonical.com>
---
 drivers/char/ipmi/ipmi_bt_sm.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/char/ipmi/ipmi_bt_sm.c b/drivers/char/ipmi/ipmi_bt_sm.c
index cdd4c09f..a22a7a5 100644
--- a/drivers/char/ipmi/ipmi_bt_sm.c
+++ b/drivers/char/ipmi/ipmi_bt_sm.c
@@ -95,9 +95,9 @@ struct si_sm_data {
 	enum bt_states	state;
 	unsigned char	seq;		/* BT sequence number */
 	struct si_sm_io	*io;
-	unsigned char	write_data[IPMI_MAX_MSG_LENGTH];
+	unsigned char	write_data[IPMI_MAX_MSG_LENGTH + 2]; /* +2 for memcpy */
 	int		write_count;
-	unsigned char	read_data[IPMI_MAX_MSG_LENGTH];
+	unsigned char	read_data[IPMI_MAX_MSG_LENGTH + 2]; /* +2 for memcpy */
 	int		read_count;
 	int		truncated;
 	long		timeout;	/* microseconds countdown */
-- 
1.8.1.2