kernel/linux.git/include/linux/netlink.h, branch v6.12.80

net: netlink: remove the cb_mutex "injection" from netlink core

2024-06-10T12:15:40+00:00

Back in 2007, in commit af65bdfce98d ("[NETLINK]: Switch cb_lock spinlock to mutex and allow to override it") netlink core was extended to allow subsystems to replace the dump mutex lock with its own lock. The mechanism was used by rtnetlink to take rtnl_lock but it isn't sufficiently flexible for other users. Over the 17 years since it was added no other user appeared. Since rtnetlink needs conditional locking now, and doesn't use it either, axe this feature complete. Signed-off-by: Jakub Kicinski Reviewed-by: Kuniyuki Iwashima Signed-off-by: David S. Miller

rtnetlink: add RTNL_FLAG_DUMP_UNLOCKED flag

2024-02-26T11:46:12+00:00

Similarly to RTNL_FLAG_DOIT_UNLOCKED, this new flag allows dump operations registered via rtnl_register() or rtnl_register_module() to opt-out from RTNL protection. Signed-off-by: Eric Dumazet Reviewed-by: Donald Hunter Signed-off-by: David S. Miller

netlink: introduce typedef for filter function

2023-12-19T14:31:40+00:00

Make the code using filter function a bit nicer by consolidating the filter function arguments using typedef. Suggested-by: Andy Shevchenko Signed-off-by: Jiri Pirko Signed-off-by: Paolo Abeni

rtnetlink: introduce nlmsg_new_large and use it in rtnl_getlink

2023-11-19T04:18:25+00:00

if a PF has 256 or more VFs, ip link command will allocate an order 3 memory or more, and maybe trigger OOM due to memory fragment, the VFs needed memory size is computed in rtnl_vfinfo_size. so introduce nlmsg_new_large which calls netlink_alloc_large_skb in which vmalloc is used for large memory, to avoid the failure of allocating memory ip invoked oom-killer: gfp_mask=0xc2cc0(GFP_KERNEL|__GFP_NOWARN|\ __GFP_COMP|__GFP_NOMEMALLOC), order=3, oom_score_adj=0 CPU: 74 PID: 204414 Comm: ip Kdump: loaded Tainted: P OE Call Trace: dump_stack+0x57/0x6a dump_header+0x4a/0x210 oom_kill_process+0xe4/0x140 out_of_memory+0x3e8/0x790 __alloc_pages_slowpath.constprop.116+0x953/0xc50 __alloc_pages_nodemask+0x2af/0x310 kmalloc_large_node+0x38/0xf0 __kmalloc_node_track_caller+0x417/0x4d0 __kmalloc_reserve.isra.61+0x2e/0x80 __alloc_skb+0x82/0x1c0 rtnl_getlink+0x24f/0x370 rtnetlink_rcv_msg+0x12c/0x350 netlink_rcv_skb+0x50/0x100 netlink_unicast+0x1b2/0x280 netlink_sendmsg+0x355/0x4a0 sock_sendmsg+0x5b/0x60 ____sys_sendmsg+0x1ea/0x250 ___sys_sendmsg+0x88/0xd0 __sys_sendmsg+0x5e/0xa0 do_syscall_64+0x33/0x40 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x7f95a65a5b70 Cc: Yunsheng Lin Signed-off-by: Li RongQing Link: https://lore.kernel.org/r/20231115120108.3711-1-lirongqing@baidu.com Signed-off-by: Jakub Kicinski

netlink: Add new netlink_release function

2023-07-23T10:34:22+00:00

A new function netlink_release is added in netlink_sock to store the protocol's release function. This is called when the socket is deleted. This can be supplied by the protocol via the release function in netlink_kernel_cfg. This is being added for the NETLINK_CONNECTOR protocol, so it can free it's data when socket is deleted. Signed-off-by: Anjali Kulkarni Reviewed-by: Liam R. Howlett Acked-by: Jakub Kicinski Signed-off-by: David S. Miller

netlink: Reverse the patch which removed filtering

2023-07-23T10:34:22+00:00

To use filtering at the connector & cn_proc layers, we need to enable filtering in the netlink layer. This reverses the patch which removed netlink filtering - commit ID for that patch: 549017aa1bb7 (netlink: remove netlink_broadcast_filtered). Signed-off-by: Anjali Kulkarni Reviewed-by: Liam R. Howlett Acked-by: Jakub Kicinski Signed-off-by: David S. Miller

netlink: support extack in dump ->start()

2023-06-12T10:32:44+00:00

Commit 4a19edb60d02 ("netlink: Pass extack to dump handlers") added extack support to netlink dumps. It was focused on rtnl and since rtnl does not use ->start(), ->done() callbacks it ignored those. Genetlink on the other hand uses ->start() extensively, for parsing and input validation. Pass the extact in via struct netlink_dump_control and link it to cb for the time of ->start(). Both struct netlink_dump_control and extack itself live on the stack so we can't keep the same extack for the duration of the dump. This means that the extack visible in ->start() and each ->dump() callbacks will be different. Corner cases like reporting a warning message in DONE across dump calls are still not supported. We could put the extack (for dumps) in the socket struct, but layering makes it slightly awkward (extack pointer is decided before the DO / DUMP split). The genetlink dump error extacks are now surfaced: $ cli.py --spec netlink/specs/ethtool.yaml --dump channels-get lib.ynl.NlError: Netlink error: Invalid argument nl_len = 64 (48) nl_flags = 0x300 nl_type = 2 error: -22 extack: {'msg': 'request header missing'} Previously extack was missing: $ cli.py --spec netlink/specs/ethtool.yaml --dump channels-get lib.ynl.NlError: Netlink error: Invalid argument nl_len = 36 (20) nl_flags = 0x100 nl_type = 2 error: -22 Signed-off-by: Jakub Kicinski Signed-off-by: David S. Miller

netlink: Add a macro to set policy message with format string

2023-03-28T02:49:58+00:00

Similar to NL_SET_ERR_MSG_FMT, add a macro which sets netlink policy error message with a format string. Signed-off-by: Shay Agroskin Signed-off-by: Jakub Kicinski

netlink: remove unused 'compare' function

2023-03-10T07:11:09+00:00

No users in the tree. Tested with allmodconfig build. Signed-off-by: Florian Westphal Link: https://lore.kernel.org/r/20230308142006.20879-1-fw@strlen.de Signed-off-by: Jakub Kicinski

netlink: provide an ability to set default extack message

2023-02-02T05:04:09+00:00

In netdev common pattern, extack pointer is forwarded to the drivers to be filled with error message. However, the caller can easily overwrite the filled message. Instead of adding multiple "if (!extack->_msg)" checks before any NL_SET_ERR_MSG() call, which appears after call to the driver, let's add new macro to common code. [1] https://lore.kernel.org/all/Y9Irgrgf3uxOjwUm@unreal Reviewed-by: Simon Horman Reviewed-by: Nikolay Aleksandrov Signed-off-by: Leon Romanovsky Link: https://lore.kernel.org/r/6993fac557a40a1973dfa0095107c3d03d40bec1.1675171790.git.leon@kernel.org Signed-off-by: Jakub Kicinski