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| author | Jakub Kicinski <kuba@kernel.org> | 2022-04-29 16:55:06 -0700 |
|---|---|---|
| committer | Paolo Abeni <pabeni@redhat.com> | 2022-05-02 15:14:20 +0200 |
| commit | c92bf26ccebc8501863b38c4a4f65b8fef28ce5e (patch) | |
| tree | 3ae147a26bf9768b022f49582df91ba2ee9cc43d /net | |
| parent | d7ab15ab34a491b3837595b629e79323a1922fc8 (diff) | |
| download | lwn-c92bf26ccebc8501863b38c4a4f65b8fef28ce5e.tar.gz lwn-c92bf26ccebc8501863b38c4a4f65b8fef28ce5e.zip | |
rtnl: allocate more attr tables on the heap
Commit a293974590cf ("rtnetlink: avoid frame size warning in rtnl_newlink()")
moved to allocating the largest attribute array of rtnl_newlink()
on the heap. Kalle reports the stack has grown above 1k again:
net/core/rtnetlink.c:3557:1: error: the frame size of 1104 bytes is larger than 1024 bytes [-Werror=frame-larger-than=]
Move more attrs to the heap, wrap them in a struct.
Don't bother with linkinfo, it's referenced a lot and we take
its size so it's awkward to move, plus it's small (6 elements).
Reported-by: Kalle Valo <kvalo@kernel.org>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Tested-by: Kalle Valo <kvalo@kernel.org>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Diffstat (limited to 'net')
| -rw-r--r-- | net/core/rtnetlink.c | 30 |
1 files changed, 18 insertions, 12 deletions
diff --git a/net/core/rtnetlink.c b/net/core/rtnetlink.c index 73f2cbc440c9..33919fd5c202 100644 --- a/net/core/rtnetlink.c +++ b/net/core/rtnetlink.c @@ -3302,17 +3302,23 @@ static int rtnl_group_changelink(const struct sk_buff *skb, return 0; } +struct rtnl_newlink_tbs { + struct nlattr *tb[IFLA_MAX + 1]; + struct nlattr *attr[RTNL_MAX_TYPE + 1]; + struct nlattr *slave_attr[RTNL_SLAVE_MAX_TYPE + 1]; +}; + static int __rtnl_newlink(struct sk_buff *skb, struct nlmsghdr *nlh, - struct nlattr **attr, struct netlink_ext_ack *extack) + struct rtnl_newlink_tbs *tbs, + struct netlink_ext_ack *extack) { - struct nlattr *slave_attr[RTNL_SLAVE_MAX_TYPE + 1]; unsigned char name_assign_type = NET_NAME_USER; struct nlattr *linkinfo[IFLA_INFO_MAX + 1]; + struct nlattr ** const tb = tbs->tb; const struct rtnl_link_ops *m_ops; struct net_device *master_dev; struct net *net = sock_net(skb->sk); const struct rtnl_link_ops *ops; - struct nlattr *tb[IFLA_MAX + 1]; struct net *dest_net, *link_net; struct nlattr **slave_data; char kind[MODULE_NAME_LEN]; @@ -3382,12 +3388,12 @@ replay: return -EINVAL; if (ops->maxtype && linkinfo[IFLA_INFO_DATA]) { - err = nla_parse_nested_deprecated(attr, ops->maxtype, + err = nla_parse_nested_deprecated(tbs->attr, ops->maxtype, linkinfo[IFLA_INFO_DATA], ops->policy, extack); if (err < 0) return err; - data = attr; + data = tbs->attr; } if (ops->validate) { err = ops->validate(tb, data, extack); @@ -3403,14 +3409,14 @@ replay: if (m_ops->slave_maxtype && linkinfo[IFLA_INFO_SLAVE_DATA]) { - err = nla_parse_nested_deprecated(slave_attr, + err = nla_parse_nested_deprecated(tbs->slave_attr, m_ops->slave_maxtype, linkinfo[IFLA_INFO_SLAVE_DATA], m_ops->slave_policy, extack); if (err < 0) return err; - slave_data = slave_attr; + slave_data = tbs->slave_attr; } } @@ -3559,15 +3565,15 @@ out_unregister: static int rtnl_newlink(struct sk_buff *skb, struct nlmsghdr *nlh, struct netlink_ext_ack *extack) { - struct nlattr **attr; + struct rtnl_newlink_tbs *tbs; int ret; - attr = kmalloc_array(RTNL_MAX_TYPE + 1, sizeof(*attr), GFP_KERNEL); - if (!attr) + tbs = kmalloc(sizeof(*tbs), GFP_KERNEL); + if (!tbs) return -ENOMEM; - ret = __rtnl_newlink(skb, nlh, attr, extack); - kfree(attr); + ret = __rtnl_newlink(skb, nlh, tbs, extack); + kfree(tbs); return ret; } |