Change RBD_MAX_SNAP_NAME_LEN to be based on NAME_MAX. That is a
practical limit for the length of a snapshot name (based on the
presence of a directory using the name under /sys/bus/rbd to
represent the snapshot).
The /sys entry is created by prefixing it with "snap_"; define that
prefix symbolically, and take its length into account in defining
the snapshot name length limit.
Enforce the limit in rbd_add_parse_args(). Also delete a dout()
call in that function that was not meant to be committed.
Signed-off-by: Alex Elder <elder@inktank.com>
Reviewed-by: Dan Mick <dan.mick@inktank.com>
Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
#define RBD_MINORS_PER_MAJOR 256 /* max minors per blkdev */
#define RBD_MINORS_PER_MAJOR 256 /* max minors per blkdev */
-#define RBD_MAX_SNAP_NAME_LEN 32
+#define RBD_SNAP_DEV_NAME_PREFIX "snap_"
+#define RBD_MAX_SNAP_NAME_LEN \
+ (NAME_MAX - (sizeof (RBD_SNAP_DEV_NAME_PREFIX) - 1))
+
#define RBD_MAX_SNAP_COUNT 510 /* allows max snapc to fit in 4KB */
#define RBD_MAX_OPT_LEN 1024
#define RBD_MAX_SNAP_COUNT 510 /* allows max snapc to fit in 4KB */
#define RBD_MAX_OPT_LEN 1024
dev->type = &rbd_snap_device_type;
dev->parent = parent;
dev->release = rbd_snap_dev_release;
dev->type = &rbd_snap_device_type;
dev->parent = parent;
dev->release = rbd_snap_dev_release;
- dev_set_name(dev, "snap_%s", snap->name);
+ dev_set_name(dev, "%s%s", RBD_SNAP_DEV_NAME_PREFIX, snap->name);
dout("%s: registering device for snapshot %s\n", __func__, snap->name);
ret = device_register(dev);
dout("%s: registering device for snapshot %s\n", __func__, snap->name);
ret = device_register(dev);
if (!rbd_dev->image_name)
goto out_err;
if (!rbd_dev->image_name)
goto out_err;
- /* Snapshot name is optional */
+ /* Snapshot name is optional; default is to use "head" */
+
+ if (len > RBD_MAX_SNAP_NAME_LEN) {
+ err_ptr = ERR_PTR(-ENAMETOOLONG);
+ goto out_err;
+ }
if (!len) {
buf = RBD_SNAP_HEAD_NAME; /* No snapshot supplied */
len = sizeof (RBD_SNAP_HEAD_NAME) - 1;
if (!len) {
buf = RBD_SNAP_HEAD_NAME; /* No snapshot supplied */
len = sizeof (RBD_SNAP_HEAD_NAME) - 1;
memcpy(snap_name, buf, len);
*(snap_name + len) = '\0';
memcpy(snap_name, buf, len);
*(snap_name + len) = '\0';
-dout(" SNAP_NAME is <%s>, len is %zd\n", snap_name, len);
-
return snap_name;
out_err:
return snap_name;
out_err: