s390/dasd: fix memleak in path handling error case

If for whatever reason the dasd_eckd_check_characteristics() function
exits after at least some paths have their configuration data
allocated those data is never freed again. In the error case the
device->private pointer is set to NULL and dasd_eckd_uncheck_device()
will exit without freeing the path data because of this NULL pointer.

Fix by calling dasd_eckd_clear_conf_data() for error cases.

Also use dasd_eckd_clear_conf_data() in dasd_eckd_uncheck_device()
to avoid code duplication.

Reported-by: Qian Cai <cai@lca.pw>
Reviewed-by: Jan Hoeppner <hoeppner@linux.ibm.com>
Signed-off-by: Stefan Haberland <sth@linux.ibm.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This commit is contained in:
Stefan Haberland 2019-12-19 09:43:51 +01:00 committed by Jens Axboe
parent dd4b3c83b9
commit 00b39f698a

View File

@ -2074,7 +2074,7 @@ dasd_eckd_check_characteristics(struct dasd_device *device)
dasd_free_block(device->block);
device->block = NULL;
out_err1:
kfree(private->conf_data);
dasd_eckd_clear_conf_data(device);
kfree(device->private);
device->private = NULL;
return rc;
@ -2083,7 +2083,6 @@ dasd_eckd_check_characteristics(struct dasd_device *device)
static void dasd_eckd_uncheck_device(struct dasd_device *device)
{
struct dasd_eckd_private *private = device->private;
int i;
if (!private)
return;
@ -2093,21 +2092,7 @@ static void dasd_eckd_uncheck_device(struct dasd_device *device)
private->sneq = NULL;
private->vdsneq = NULL;
private->gneq = NULL;
private->conf_len = 0;
for (i = 0; i < 8; i++) {
kfree(device->path[i].conf_data);
if ((__u8 *)device->path[i].conf_data ==
private->conf_data) {
private->conf_data = NULL;
private->conf_len = 0;
}
device->path[i].conf_data = NULL;
device->path[i].cssid = 0;
device->path[i].ssid = 0;
device->path[i].chpid = 0;
}
kfree(private->conf_data);
private->conf_data = NULL;
dasd_eckd_clear_conf_data(device);
}
static struct dasd_ccw_req *