On Thu, Feb 09, 2023 at 12:04:23PM +0100, Alexandra Winter wrote:
> From: Thorsten Winkler <twinkler@xxxxxxxxxxxxx>
>
> Following the advice of the Documentation/filesystems/sysfs.rst.
> All sysfs related show()-functions should only use sysfs_emit() or
> sysfs_emit_at() when formatting the value to be returned to user space.
>
> Reported-by: Jules Irenge <jbi.octave@xxxxxxxxx>
> Reported-by: Joe Perches <joe@xxxxxxxxxxx>
> Reviewed-by: Alexandra Winter <wintera@xxxxxxxxxxxxx>
> Signed-off-by: Thorsten Winkler <twinkler@xxxxxxxxxxxxx>
> Signed-off-by: Alexandra Winter <wintera@xxxxxxxxxxxxx>
...
> diff --git a/drivers/s390/net/qeth_l3_sys.c b/drivers/s390/net/qeth_l3_sys.c
> index 6143dd485810..f3986c6e21b9 100644
> --- a/drivers/s390/net/qeth_l3_sys.c
> +++ b/drivers/s390/net/qeth_l3_sys.c
...
> @@ -367,35 +367,21 @@ static ssize_t qeth_l3_dev_ipato_add_show(char *buf, struct qeth_card *card,
> enum qeth_prot_versions proto)
> {
> struct qeth_ipato_entry *ipatoe;
> - int str_len = 0;
> + char addr_str[INET6_ADDRSTRLEN];
> + int offset = 0;
>
> mutex_lock(&card->ip_lock);
> list_for_each_entry(ipatoe, &card->ipato.entries, entry) {
> - char addr_str[INET6_ADDRSTRLEN];
> - int entry_len;
> -
> if (ipatoe->proto != proto)
> continue;
>
> - entry_len = qeth_l3_ipaddr_to_string(proto, ipatoe->addr,
> - addr_str);
> - if (entry_len < 0)
> - continue;
Here the return code of qeth_l3_ipaddr_to_string() is checked for an error.
> -
> - /* Append /%mask to the entry: */
> - entry_len += 1 + ((proto == QETH_PROT_IPV4) ? 2 : 3);
> - /* Enough room to format %entry\n into null terminated page? */
> - if (entry_len + 1 > PAGE_SIZE - str_len - 1)
> - break;
> -
> - entry_len = scnprintf(buf, PAGE_SIZE - str_len,
> - "%s/%i\n", addr_str, ipatoe->mask_bits);
> - str_len += entry_len;
> - buf += entry_len;
> + qeth_l3_ipaddr_to_string(proto, ipatoe->addr, addr_str);
But here it is not. Is that ok?
Likewise in qeth_l3_dev_ip_add_show().
> + offset += sysfs_emit_at(buf, offset, "%s/%i\n",
> + addr_str, ipatoe->mask_bits);
> }
> mutex_unlock(&card->ip_lock);
>
> - return str_len ? str_len : scnprintf(buf, PAGE_SIZE, "\n");
> + return offset ? offset : sysfs_emit(buf, "\n");
> }
>
> static ssize_t qeth_l3_dev_ipato_add4_show(struct device *dev,
> @@ -501,7 +487,7 @@ static ssize_t qeth_l3_dev_ipato_invert6_show(struct device *dev,
> {
> struct qeth_card *card = dev_get_drvdata(dev);
>
> - return sprintf(buf, "%u\n", card->ipato.invert6 ? 1 : 0);
> + return sysfs_emit(buf, "%u\n", card->ipato.invert6 ? 1 : 0);
> }
>
> static ssize_t qeth_l3_dev_ipato_invert6_store(struct device *dev,
> @@ -586,35 +572,22 @@ static ssize_t qeth_l3_dev_ip_add_show(struct device *dev, char *buf,
> enum qeth_ip_types type)
> {
> struct qeth_card *card = dev_get_drvdata(dev);
> + char addr_str[INET6_ADDRSTRLEN];
> struct qeth_ipaddr *ipaddr;
> - int str_len = 0;
> + int offset = 0;
> int i;
>
> mutex_lock(&card->ip_lock);
> hash_for_each(card->ip_htable, i, ipaddr, hnode) {
> - char addr_str[INET6_ADDRSTRLEN];
> - int entry_len;
> -
> if (ipaddr->proto != proto || ipaddr->type != type)
> continue;
>
> - entry_len = qeth_l3_ipaddr_to_string(proto, (u8 *)&ipaddr->u,
> - addr_str);
> - if (entry_len < 0)
> - continue;
> -
> - /* Enough room to format %addr\n into null terminated page? */
> - if (entry_len + 1 > PAGE_SIZE - str_len - 1)
> - break;
> -
> - entry_len = scnprintf(buf, PAGE_SIZE - str_len, "%s\n",
> - addr_str);
> - str_len += entry_len;
> - buf += entry_len;
> + qeth_l3_ipaddr_to_string(proto, (u8 *)&ipaddr->u, addr_str);
> + offset += sysfs_emit_at(buf, offset, "%s\n", addr_str);
> }
> mutex_unlock(&card->ip_lock);
>
> - return str_len ? str_len : scnprintf(buf, PAGE_SIZE, "\n");
> + return offset ? offset : sysfs_emit(buf, "\n");
> }
>
> static ssize_t qeth_l3_dev_vipa_add4_show(struct device *dev,
> --
> 2.37.2
>
