[PATCH] drivers: staging: ft1000: ft1000-usb: ft1000_debug.c: check return value of get_user() in ft1000_ioctl()

Chen Gang
2013-11-27T03:38:52Z

get_user() may fail and cause 'msgsz' uninitialized, so need give a
check. The related warning (with allmodconfig under hexagon):

CC [M] drivers/staging/ft1000/ft1000-usb/ft1000_debug.o
drivers/staging/ft1000/ft1000-usb/ft1000_debug.c: In function 'ft1000_ioctl':
include/uapi/linux/swab.h:53:9: warning: 'msgsz' may be used uninitialized in this function [-Wuninitialized]
drivers/staging/ft1000/ft1000-usb/ft1000_debug.c:533:17: note: 'msgsz' was declared here

Signed-off-by: Chen Gang <gang.chen.5i5j@gmail.com>
---
drivers/staging/ft1000/ft1000-usb/ft1000_debug.c | 2 ++
1 files changed, 2 insertions(+), 0 deletions(-)

diff --git a/drivers/staging/ft1000/ft1000-usb/ft1000_debug.c b/drivers/staging/ft1000/ft1000-usb/ft1000_debug.c
index 68a55ce..ffdc7f5 100644
--- a/drivers/staging/ft1000/ft1000-usb/ft1000_debug.c
+++ b/drivers/staging/ft1000/ft1000-usb/ft1000_debug.c
@@ -560,6 +560,8 @@ static long ft1000_ioctl(struct file *file, unsigned int command,

/* Get the length field to see how many bytes to copy */
result = get_user(msgsz, (__u16 __user *)argp);
+ if (result)
+ break;
msgsz = ntohs(msgsz);
/* DEBUG("FT1000:ft1000_ioctl: length of message = %d\n", msgsz); */

--
1.7.7.6