kernel/linux.git/include/net/netlink.h, branch v7.2-rc1

netlink: add one debug check in nla_nest_end()

2026-05-14T23:49:26+00:00

Add a DEBUG_NET_WARN_ON_ONCE(diff > U16_MAX) to warn if the kernel sends corrupted nested attribute to user space. Offenders can be converted to nla_nest_end_safe(). Signed-off-by: Eric Dumazet Link: https://patch.msgid.link/20260512155244.4137851-1-edumazet@google.com Signed-off-by: Jakub Kicinski

netlink: add a nla_nest_end_safe() helper

2026-04-12T18:23:50+00:00

The nla_len field in struct nlattr is a __u16, which can only hold values up to 65535. If a nested attribute grows beyond this limit, nla_nest_end() silently truncates the length, producing a corrupted netlink message with no indication of the problem. Since nla_nest_end() is used everywhere and this issue rarely happens, let's add a new helper to check the length. Signed-off-by: Hangbin Liu Link: https://patch.msgid.link/20260408-b4-ynl_ethtool-v2-4-7623a5e8f70b@gmail.com Signed-off-by: Jakub Kicinski

netlink: introduce type-checking attribute iteration for nlmsg

2025-07-02T22:39:04+00:00

Add the nlmsg_for_each_attr_type() macro to simplify iteration over attributes of a specific type in a Netlink message. Convert existing users in vxlan and nfsd to use the new macro. Suggested-by: Jakub Kicinski Signed-off-by: Carolina Jubran Signed-off-by: Mark Bloch Link: https://patch.msgid.link/20250629142138.361537-2-mbloch@nvidia.com Signed-off-by: Jakub Kicinski

netlink: fix policy dump for int with validation callback

2025-05-13T01:50:09+00:00

Recent devlink change added validation of an integer value via NLA_POLICY_VALIDATE_FN, for sparse enums. Handle this in policy dump. We can't extract any info out of the callback, so report only the type. Fixes: 429ac6211494 ("devlink: define enum for attr types of dynamic attributes") Reported-by: syzbot+01eb26848144516e7f0a@syzkaller.appspotmail.com Link: https://patch.msgid.link/20250509212751.1905149-1-kuba@kernel.org Signed-off-by: Jakub Kicinski

netlink: Introduce nlmsg_payload helper

2025-04-15T15:28:53+00:00

Create a new helper function, nlmsg_payload(), to simplify checking and retrieving Netlink message payloads. This reduces boilerplate code for users who need to verify the message length before accessing its data. Suggested-by: Jakub Kicinski Signed-off-by: Breno Leitao Reviewed-by: Jakub Kicinski Reviewed-by: Kuniyuki Iwashima Link: https://patch.msgid.link/20250414-nlmsg-v2-1-3d90cb42c6af@debian.org Signed-off-by: Jakub Kicinski

netlink: Add nla_put_empty_nest helper

2025-02-18T00:46:03+00:00

Creating empty nests is helpful when the exact attributes to be exposed in the future are not known. Encapsulate the logic in a helper. Signed-off-by: Joe Damato Suggested-by: Jakub Kicinski Link: https://patch.msgid.link/20250214211255.14194-2-jdamato@fastly.com Signed-off-by: Jakub Kicinski

net: reformat kdoc return statements

2024-12-09T22:44:59+00:00

kernel-doc -Wall warns about missing Return: statement for non-void functions. We have a number of kdocs in our headers which are missing the colon, IOW they use * Return some value or * Returns some value Having the colon makes some sense, it should help kdoc parser avoid false positives. So add them. This is mostly done with a sed script, and removing the unnecessary cases (mostly the comments which aren't kdoc). Acked-by: Johannes Berg Acked-by: Richard Cochran Acked-by: Sergey Ryazanov Reviewed-by: Edward Cree Acked-by: Alexandra Winter Acked-by: Pablo Neira Ayuso Link: https://patch.msgid.link/20241205165914.1071102-1-kuba@kernel.org Signed-off-by: Jakub Kicinski

net: netlink: add nla_get_*_default() accessors

2024-11-11T18:32:06+00:00

There are quite a number of places that use patterns such as if (attr) val = nla_get_u16(attr); else val = DEFAULT; Add nla_get_u16_default() and friends like that to not have to type this out all the time. Acked-by: Toke Høiland-Jørgensen Acked-by: Jakub Kicinski Signed-off-by: Johannes Berg Link: https://patch.msgid.link/20241108114145.acd2aadb03ac.I3df6aac71d38a5baa1c0a03d0c7e82d4395c030e@changeid Signed-off-by: Jakub Kicinski

netlink: add NLA_POLICY_MAX_LEN macro

2024-11-01T02:10:52+00:00

Similarly to NLA_POLICY_MIN_LEN, NLA_POLICY_MAX_LEN defines a policy with a maximum length value. The netlink generator for YAML specs has been extended accordingly. Signed-off-by: Antonio Quartulli Reviewed-by: Donald Hunter Link: https://patch.msgid.link/20241029-b4-ovpn-v11-1-de4698c73a25@openvpn.net Signed-off-by: Jakub Kicinski

net: Correct spelling in headers

2024-08-26T16:37:23+00:00

Correct spelling in Networking headers. As reported by codespell. Signed-off-by: Simon Horman Link: https://patch.msgid.link/20240822-net-spell-v1-12-3a98971ce2d2@kernel.org Signed-off-by: Jakub Kicinski