[PATCH v2] media: rc: ir-lirc-codec: fix integer overflow

From: Vasiliy Kulikov
Date: Sat Dec 04 2010 - 16:05:35 EST


'n' may be bigger than MAX_INT*sizeof(int), if so checking of truncated
(int)(n/sizeof(int)) for LIRCBUF_SIZE overflows and then using nontruncated 'count'
doesn't make sense. This is not a security issue as too big 'n' is catched in
kmalloc() in memdup_user() call. However, it's better to prevent WARN() in kmalloc().

Signed-off-by: Vasiliy Kulikov <segoon@xxxxxxxxxxxx>
---
Compile tested only.

drivers/media/rc/ir-lirc-codec.c | 3 ++-
1 files changed, 2 insertions(+), 1 deletions(-)

diff --git a/drivers/media/rc/ir-lirc-codec.c b/drivers/media/rc/ir-lirc-codec.c
index 1e87ee8..a7e91e6 100644
--- a/drivers/media/rc/ir-lirc-codec.c
+++ b/drivers/media/rc/ir-lirc-codec.c
@@ -100,7 +100,8 @@ static ssize_t ir_lirc_transmit_ir(struct file *file, const char *buf,
struct lirc_codec *lirc;
struct rc_dev *dev;
int *txbuf; /* buffer with values to transmit */
- int ret = 0, count;
+ int ret = 0;
+ size_t count;

lirc = lirc_get_pdata(file);
if (!lirc)
--
1.7.0.4
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