cdrom: information leak in cdrom_ioctl_media_changed()
This cast is wrong. "cdi->capacity" is an int and "arg" is an unsigned
long. The way the check is written now, if one of the high 32 bits is
set then we could read outside the info->slots[] array.
This bug is pretty old and it predates git.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Cc: stable@vger.kernel.org
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
diff --git a/drivers/cdrom/cdrom.c b/drivers/cdrom/cdrom.c
index 8327478..bfc566d 100644
--- a/drivers/cdrom/cdrom.c
+++ b/drivers/cdrom/cdrom.c
@@ -2371,7 +2371,7 @@ static int cdrom_ioctl_media_changed(struct cdrom_device_info *cdi,
if (!CDROM_CAN(CDC_SELECT_DISC) || arg == CDSL_CURRENT)
return media_changed(cdi, 1);
- if ((unsigned int)arg >= cdi->capacity)
+ if (arg >= cdi->capacity)
return -EINVAL;
info = kmalloc(sizeof(*info), GFP_KERNEL);