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>
This commit is contained in:
Dan Carpenter 2018-04-18 12:51:31 +03:00 коммит произвёл Jens Axboe
Родитель 72961c4e60
Коммит 9de4ee4054
1 изменённых файлов: 1 добавлений и 1 удалений

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@ -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);