From 2d76443e02f260d7a5bd0ede1851ae5534f0c68d Mon Sep 17 00:00:00 2001 From: Mike Christie Date: Mon, 12 Jun 2017 01:34:28 -0500 Subject: tcmu: reconfigure netlink attr changes 1. TCMU_ATTR_TYPE is too generic when it describes only the reconfiguration type, so rename to TCMU_ATTR_RECONFIG_TYPE. 2. Only return the reconfig type when it is a TCMU_CMD_RECONFIG_DEVICE command. 3. CONFIG_* type is not needed. We can pass the value along with an ATTR to userspace, so it does not need to read sysfs/configfs. 4. Fix leak in tcmu_dev_path_store and rename to dev_config to reflect it is more than just a path that can be changed. 6. Don't update kernel struct value if netlink sending fails. Signed-off-by: Mike Christie Reviewed-by: "Bryant G. Ly" Signed-off-by: Nicholas Bellinger --- drivers/target/target_core_user.c | 73 +++++++++++++++++++++++---------------- 1 file changed, 44 insertions(+), 29 deletions(-) (limited to 'drivers/target') diff --git a/drivers/target/target_core_user.c b/drivers/target/target_core_user.c index 6322269d9e85..ca5b081295db 100644 --- a/drivers/target/target_core_user.c +++ b/drivers/target/target_core_user.c @@ -1177,7 +1177,8 @@ static int tcmu_release(struct uio_info *info, struct inode *inode) } static int tcmu_netlink_event(enum tcmu_genl_cmd cmd, const char *name, - int minor, int type) + int minor, int reconfig_attr, + const void *reconfig_data) { struct sk_buff *skb; void *msg_header; @@ -1199,9 +1200,27 @@ static int tcmu_netlink_event(enum tcmu_genl_cmd cmd, const char *name, if (ret < 0) goto free_skb; - ret = nla_put_u32(skb, TCMU_ATTR_TYPE, type); - if (ret < 0) - goto free_skb; + if (cmd == TCMU_CMD_RECONFIG_DEVICE) { + switch (reconfig_attr) { + case TCMU_ATTR_DEV_CFG: + ret = nla_put_string(skb, reconfig_attr, reconfig_data); + break; + case TCMU_ATTR_DEV_SIZE: + ret = nla_put_u64_64bit(skb, reconfig_attr, + *((u64 *)reconfig_data), + TCMU_ATTR_PAD); + break; + case TCMU_ATTR_WRITECACHE: + ret = nla_put_u8(skb, reconfig_attr, + *((u8 *)reconfig_data)); + break; + default: + BUG(); + } + + if (ret < 0) + goto free_skb; + } genlmsg_end(skb, msg_header); @@ -1306,7 +1325,7 @@ static int tcmu_configure_device(struct se_device *dev) kref_get(&udev->kref); ret = tcmu_netlink_event(TCMU_CMD_ADDED_DEVICE, udev->uio_info.name, - udev->uio_info.uio_dev->minor, NO_RECONFIG); + udev->uio_info.uio_dev->minor, 0, NULL); if (ret) goto err_netlink; @@ -1388,7 +1407,7 @@ static void tcmu_free_device(struct se_device *dev) if (tcmu_dev_configured(udev)) { tcmu_netlink_event(TCMU_CMD_REMOVED_DEVICE, udev->uio_info.name, - udev->uio_info.uio_dev->minor, NO_RECONFIG); + udev->uio_info.uio_dev->minor, 0, NULL); uio_unregister_device(&udev->uio_info); } @@ -1553,7 +1572,7 @@ static ssize_t tcmu_cmd_time_out_store(struct config_item *item, const char *pag } CONFIGFS_ATTR(tcmu_, cmd_time_out); -static ssize_t tcmu_dev_path_show(struct config_item *item, char *page) +static ssize_t tcmu_dev_config_show(struct config_item *item, char *page) { struct se_dev_attrib *da = container_of(to_config_group(item), struct se_dev_attrib, da_group); @@ -1562,37 +1581,34 @@ static ssize_t tcmu_dev_path_show(struct config_item *item, char *page) return snprintf(page, PAGE_SIZE, "%s\n", udev->dev_config); } -static ssize_t tcmu_dev_path_store(struct config_item *item, const char *page, - size_t count) +static ssize_t tcmu_dev_config_store(struct config_item *item, const char *page, + size_t count) { struct se_dev_attrib *da = container_of(to_config_group(item), struct se_dev_attrib, da_group); struct tcmu_dev *udev = TCMU_DEV(da->da_dev); - char *copy = NULL; - int ret; + int ret, len; - copy = kstrdup(page, GFP_KERNEL); - if (!copy) { - kfree(copy); + len = strlen(page); + if (!len || len > TCMU_CONFIG_LEN - 1) return -EINVAL; - } - strlcpy(udev->dev_config, copy, TCMU_CONFIG_LEN); /* Check if device has been configured before */ if (tcmu_dev_configured(udev)) { ret = tcmu_netlink_event(TCMU_CMD_RECONFIG_DEVICE, udev->uio_info.name, udev->uio_info.uio_dev->minor, - CONFIG_PATH); + TCMU_ATTR_DEV_CFG, page); if (ret) { pr_err("Unable to reconfigure device\n"); return ret; } } + strlcpy(udev->dev_config, page, TCMU_CONFIG_LEN); return count; } -CONFIGFS_ATTR(tcmu_, dev_path); +CONFIGFS_ATTR(tcmu_, dev_config); static ssize_t tcmu_dev_size_show(struct config_item *item, char *page) { @@ -1609,26 +1625,25 @@ static ssize_t tcmu_dev_size_store(struct config_item *item, const char *page, struct se_dev_attrib *da = container_of(to_config_group(item), struct se_dev_attrib, da_group); struct tcmu_dev *udev = TCMU_DEV(da->da_dev); - unsigned long val; + u64 val; int ret; - ret = kstrtoul(page, 0, &val); + ret = kstrtou64(page, 0, &val); if (ret < 0) return ret; - udev->dev_size = val; /* Check if device has been configured before */ if (tcmu_dev_configured(udev)) { ret = tcmu_netlink_event(TCMU_CMD_RECONFIG_DEVICE, udev->uio_info.name, udev->uio_info.uio_dev->minor, - CONFIG_SIZE); + TCMU_ATTR_DEV_SIZE, &val); if (ret) { pr_err("Unable to reconfigure device\n"); return ret; } } - + udev->dev_size = val; return count; } CONFIGFS_ATTR(tcmu_, dev_size); @@ -1648,33 +1663,33 @@ static ssize_t tcmu_emulate_write_cache_store(struct config_item *item, struct se_dev_attrib *da = container_of(to_config_group(item), struct se_dev_attrib, da_group); struct tcmu_dev *udev = TCMU_DEV(da->da_dev); - int val; + u8 val; int ret; - ret = kstrtouint(page, 0, &val); + ret = kstrtou8(page, 0, &val); if (ret < 0) return ret; - da->emulate_write_cache = val; - /* Check if device has been configured before */ if (tcmu_dev_configured(udev)) { ret = tcmu_netlink_event(TCMU_CMD_RECONFIG_DEVICE, udev->uio_info.name, udev->uio_info.uio_dev->minor, - CONFIG_WRITECACHE); + TCMU_ATTR_WRITECACHE, &val); if (ret) { pr_err("Unable to reconfigure device\n"); return ret; } } + + da->emulate_write_cache = val; return count; } CONFIGFS_ATTR(tcmu_, emulate_write_cache); static struct configfs_attribute *tcmu_attrib_attrs[] = { &tcmu_attr_cmd_time_out, - &tcmu_attr_dev_path, + &tcmu_attr_dev_config, &tcmu_attr_dev_size, &tcmu_attr_emulate_write_cache, NULL, -- cgit v1.2.3