diff options
Diffstat (limited to 'drivers/md')
| -rw-r--r-- | drivers/md/dm-ioctl.c | 64 |
1 files changed, 41 insertions, 23 deletions
diff --git a/drivers/md/dm-ioctl.c b/drivers/md/dm-ioctl.c index eee353da374..9ae11b2994f 100644 --- a/drivers/md/dm-ioctl.c +++ b/drivers/md/dm-ioctl.c @@ -1478,39 +1478,52 @@ static int target_message(struct dm_ioctl *param, size_t param_size) return r; } +/* + * The ioctl parameter block consists of two parts, a dm_ioctl struct + * followed by a data buffer. This flag is set if the second part, + * which has a variable size, is not used by the function processing + * the ioctl. + */ +#define IOCTL_FLAGS_NO_PARAMS 1 + /*----------------------------------------------------------------- * Implementation of open/close/ioctl on the special char * device. *---------------------------------------------------------------*/ -static ioctl_fn lookup_ioctl(unsigned int cmd) +static ioctl_fn lookup_ioctl(unsigned int cmd, int *ioctl_flags) { static struct { int cmd; + int flags; ioctl_fn fn; } _ioctls[] = { - {DM_VERSION_CMD, NULL}, /* version is dealt with elsewhere */ - {DM_REMOVE_ALL_CMD, remove_all}, - {DM_LIST_DEVICES_CMD, list_devices}, - - {DM_DEV_CREATE_CMD, dev_create}, - {DM_DEV_REMOVE_CMD, dev_remove}, - {DM_DEV_RENAME_CMD, dev_rename}, - {DM_DEV_SUSPEND_CMD, dev_suspend}, - {DM_DEV_STATUS_CMD, dev_status}, - {DM_DEV_WAIT_CMD, dev_wait}, - - {DM_TABLE_LOAD_CMD, table_load}, - {DM_TABLE_CLEAR_CMD, table_clear}, - {DM_TABLE_DEPS_CMD, table_deps}, - {DM_TABLE_STATUS_CMD, table_status}, - - {DM_LIST_VERSIONS_CMD, list_versions}, - - {DM_TARGET_MSG_CMD, target_message}, - {DM_DEV_SET_GEOMETRY_CMD, dev_set_geometry} + {DM_VERSION_CMD, 0, NULL}, /* version is dealt with elsewhere */ + {DM_REMOVE_ALL_CMD, IOCTL_FLAGS_NO_PARAMS, remove_all}, + {DM_LIST_DEVICES_CMD, 0, list_devices}, + + {DM_DEV_CREATE_CMD, IOCTL_FLAGS_NO_PARAMS, dev_create}, + {DM_DEV_REMOVE_CMD, IOCTL_FLAGS_NO_PARAMS, dev_remove}, + {DM_DEV_RENAME_CMD, 0, dev_rename}, + {DM_DEV_SUSPEND_CMD, IOCTL_FLAGS_NO_PARAMS, dev_suspend}, + {DM_DEV_STATUS_CMD, IOCTL_FLAGS_NO_PARAMS, dev_status}, + {DM_DEV_WAIT_CMD, 0, dev_wait}, + + {DM_TABLE_LOAD_CMD, 0, table_load}, + {DM_TABLE_CLEAR_CMD, IOCTL_FLAGS_NO_PARAMS, table_clear}, + {DM_TABLE_DEPS_CMD, 0, table_deps}, + {DM_TABLE_STATUS_CMD, 0, table_status}, + + {DM_LIST_VERSIONS_CMD, 0, list_versions}, + + {DM_TARGET_MSG_CMD, 0, target_message}, + {DM_DEV_SET_GEOMETRY_CMD, 0, dev_set_geometry} }; - return (cmd >= ARRAY_SIZE(_ioctls)) ? NULL : _ioctls[cmd].fn; + if (unlikely(cmd >= ARRAY_SIZE(_ioctls))) + return NULL; + + *ioctl_flags = _ioctls[cmd].flags; + return _ioctls[cmd].fn; } /* @@ -1652,6 +1665,7 @@ static int validate_params(uint cmd, struct dm_ioctl *param) static int ctl_ioctl(uint command, struct dm_ioctl __user *user) { int r = 0; + int ioctl_flags; int param_flags; unsigned int cmd; struct dm_ioctl *uninitialized_var(param); @@ -1681,7 +1695,7 @@ static int ctl_ioctl(uint command, struct dm_ioctl __user *user) if (cmd == DM_VERSION_CMD) return 0; - fn = lookup_ioctl(cmd); + fn = lookup_ioctl(cmd, &ioctl_flags); if (!fn) { DMWARN("dm_ctl_ioctl: unknown command 0x%x", command); return -ENOTTY; @@ -1703,6 +1717,10 @@ static int ctl_ioctl(uint command, struct dm_ioctl __user *user) param->data_size = sizeof(*param); r = fn(param, input_param_size); + if (unlikely(param->flags & DM_BUFFER_FULL_FLAG) && + unlikely(ioctl_flags & IOCTL_FLAGS_NO_PARAMS)) + DMERR("ioctl %d tried to output some data but has IOCTL_FLAGS_NO_PARAMS set", cmd); + /* * Copy the results back to userland. */ |