We can't allow more than one stats attribute which uses the local idx
since the result will be a mess. This is a simple check to make sure
only one is being used at a time. Later when the filter_mask's 32 bits
are over we can switch to a bitmap.
Signed-off-by: Nikolay Aleksandrov <niko...@cumulusnetworks.com>
---
include/net/rtnetlink.h | 6 ++++++
net/core/rtnetlink.c | 17 +++++++++++++++--
2 files changed, 21 insertions(+), 2 deletions(-)
diff --git a/include/net/rtnetlink.h b/include/net/rtnetlink.h
index 2f87c1ba13de..3f3b0b1b8722 100644
--- a/include/net/rtnetlink.h
+++ b/include/net/rtnetlink.h
@@ -150,4 +150,10 @@ int rtnl_nla_parse_ifla(struct nlattr **tb, const struct
nlattr *head, int len);
#define MODULE_ALIAS_RTNL_LINK(kind) MODULE_ALIAS("rtnl-link-" kind)
+/* at most one attribute which can save a local idx is allowed to be set
+ * IFLA_STATS_IDX_ATTR_MASK has all the idx saving attributes set and is
+ * used to check if more than one is being requested
+ */
+#define IFLA_STATS_IDX_ATTR_MASK 0
+
#endif
diff --git a/net/core/rtnetlink.c b/net/core/rtnetlink.c
index aeb2fa9b1cda..ea03b6cd3d3c 100644
--- a/net/core/rtnetlink.c
+++ b/net/core/rtnetlink.c
@@ -3512,7 +3512,7 @@ static int rtnl_stats_get(struct sk_buff *skb, struct
nlmsghdr *nlh)
struct if_stats_msg *ifsm;
struct net_device *dev = NULL;
struct sk_buff *nskb;
- u32 filter_mask;
+ u32 filter_mask, lidx_filter;
int lidx = 0;
int err;
@@ -3529,6 +3529,14 @@ static int rtnl_stats_get(struct sk_buff *skb, struct
nlmsghdr *nlh)
if (!filter_mask)
return -EINVAL;
+ /* only one attribute which can save a local idx is allowed at a time
+ * even though rtnl_stats_get doesn't save the lidx, we need to be
+ * consistent with the dump side and error out
+ */
+ lidx_filter = filter_mask & IFLA_STATS_IDX_ATTR_MASK;
+ if (lidx_filter && !is_power_of_2(lidx_filter))
+ return -EINVAL;
+
nskb = nlmsg_new(if_nlmsg_stats_size(dev, filter_mask), GFP_KERNEL);
if (!nskb)
return -ENOBUFS;
@@ -3556,7 +3564,7 @@ static int rtnl_stats_dump(struct sk_buff *skb, struct
netlink_callback *cb)
struct net_device *dev;
struct hlist_head *head;
unsigned int flags = NLM_F_MULTI;
- u32 filter_mask = 0;
+ u32 filter_mask = 0, lidx_filter;
int err;
s_h = cb->args[0];
@@ -3570,6 +3578,11 @@ static int rtnl_stats_dump(struct sk_buff *skb, struct
netlink_callback *cb)
if (!filter_mask)
return -EINVAL;
+ /* only one attribute which can save a local idx is allowed at a time */
+ lidx_filter = filter_mask & IFLA_STATS_IDX_ATTR_MASK;
+ if (lidx_filter && !is_power_of_2(lidx_filter))
+ return -EINVAL;
+
for (h = s_h; h < NETDEV_HASHENTRIES; h++, s_idx = 0) {
idx = 0;
head = &net->dev_index_head[h];
--
2.4.11
