[PATCH 3.12 08/72] Char: ipmi_bt_sm, fix infinite loop

[Jiri Slaby]

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

===============

commit a94cdd1f4d30f12904ab528152731fb13a812a16 upstream.

In read_all_bytes, we do

  unsigned char i;
  ...
  bt->read_data[0] = BMC2HOST;
  bt->read_count = bt->read_data[0];
  ...
  for (i = 1; i <= bt->read_count; i++)
    bt->read_data[i] = BMC2HOST;

If bt->read_data[0] == bt->read_count == 255, we loop infinitely in the
'for' loop.  Make 'i' an 'int' instead of 'char' to get rid of the
overflow and finish the loop after 255 iterations every time.

Signed-off-by: Jiri Slaby <jslaby@xxxxxxx>
Reported-and-debugged-by: Rui Hui Dian <rhdian@xxxxxxxxxx>
Cc: Tomas Cech <tcech@xxxxxxx>
Cc: Corey Minyard <minyard@xxxxxxx>
Cc: <openipmi-developer@xxxxxxxxxxxxxxxxxxxxx>
Signed-off-by: Corey Minyard <cminyard@xxxxxxxxxx>
Signed-off-by: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx>
Signed-off-by: Jiri Slaby <jslaby@xxxxxxx>
---
 drivers/char/ipmi/ipmi_bt_sm.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/char/ipmi/ipmi_bt_sm.c b/drivers/char/ipmi/ipmi_bt_sm.c
index a22a7a502740..8156cafad11a 100644
--- a/drivers/char/ipmi/ipmi_bt_sm.c
+++ b/drivers/char/ipmi/ipmi_bt_sm.c
@@ -352,7 +352,7 @@ static inline void write_all_bytes(struct si_sm_data *bt)
 
 static inline int read_all_bytes(struct si_sm_data *bt)
 {
-	unsigned char i;
+	unsigned int i;
 
 	/*
 	 * length is "framing info", minimum = 4: NetFn, Seq, Cmd, cCode.
-- 
1.9.2

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/