kernel/linux.git/net/core/dst_cache.c, branch v6.19.11

net: dst: annotate data-races around dst->obsolete

2025-07-02T21:32:29+00:00

(dst_entry)->obsolete is read locklessly, add corresponding annotations. Signed-off-by: Eric Dumazet Reviewed-by: Kuniyuki Iwashima Link: https://patch.msgid.link/20250630121934.3399505-2-edumazet@google.com Signed-off-by: Jakub Kicinski

net: dst_cache: Use nested-BH locking for dst_cache::cache

2025-05-15T13:23:30+00:00

dst_cache::cache is a per-CPU variable and relies on disabled BH for its locking. Without per-CPU locking in local_bh_disable() on PREEMPT_RT this data structure requires explicit locking. Add a local_lock_t to the data structure and use local_lock_nested_bh() for locking. This change adds only lockdep coverage and does not alter the functional behaviour for !PREEMPT_RT. Signed-off-by: Sebastian Andrzej Siewior Link: https://patch.msgid.link/20250512092736.229935-3-bigeasy@linutronix.de Signed-off-by: Paolo Abeni

net: dst_cache: add two DEBUG_NET warnings

2024-06-04T01:50:09+00:00

After fixing four different bugs involving dst_cache users, it might be worth adding a check about BH being blocked by dst_cache callers. DEBUG_NET_WARN_ON_ONCE(!in_softirq()); It is not fatal, if we missed valid case where no BH deadlock is to be feared, we might change this. Signed-off-by: Eric Dumazet Acked-by: Paolo Abeni Link: https://lore.kernel.org/r/20240531132636.2637995-6-edumazet@google.com Signed-off-by: Jakub Kicinski

net: dst_cache: minor optimization in dst_cache_set_ip6()

2024-05-09T01:50:11+00:00

There is no need to use this_cpu_ptr(dst_cache->cache) twice. Compiler is unable to optimize the second call, because of per-cpu constraints. Signed-off-by: Eric Dumazet Acked-by: Paolo Abeni Link: https://lore.kernel.org/r/20240507132717.627518-1-edumazet@google.com Signed-off-by: Jakub Kicinski

net: dst_cache: annotate data-races around dst_cache->reset_ts

2024-05-09T01:49:51+00:00

dst_cache->reset_ts is read or written locklessly, add READ_ONCE() and WRITE_ONCE() annotations. Signed-off-by: Eric Dumazet Acked-by: Paolo Abeni Link: https://lore.kernel.org/r/20240507132000.614591-1-edumazet@google.com Signed-off-by: Jakub Kicinski

inet: introduce dst_rtable() helper

2024-05-01T01:32:38+00:00

I added dst_rt6_info() in commit e8dfd42c17fa ("ipv6: introduce dst_rt6_info() helper") This patch does a similar change for IPv4. Instead of (struct rtable *)dst casts, we can use : #define dst_rtable(_ptr) \ container_of_const(_ptr, struct rtable, dst) Patch is smaller than IPv6 one, because IPv4 has skb_rtable() helper. Signed-off-by: Eric Dumazet Reviewed-by: David Ahern Reviewed-by: Sabrina Dubroca Link: https://lore.kernel.org/r/20240429133009.1227754-1-edumazet@google.com Signed-off-by: Jakub Kicinski

ipv6: introduce dst_rt6_info() helper

2024-04-29T12:32:01+00:00

Instead of (struct rt6_info *)dst casts, we can use : #define dst_rt6_info(_ptr) \ container_of_const(_ptr, struct rt6_info, dst) Some places needed missing const qualifiers : ip6_confirm_neigh(), ipv6_anycast_destination(), ipv6_unicast_destination(), has_gateway() v2: added missing parts (David Ahern) Signed-off-by: Eric Dumazet Reviewed-by: David Ahern Signed-off-by: David S. Miller

wireguard: device: reset peer src endpoint when netns exits

2021-11-30T03:50:45+00:00

Each peer's endpoint contains a dst_cache entry that takes a reference to another netdev. When the containing namespace exits, we take down the socket and prevent future sockets from being created (by setting creating_net to NULL), which removes that potential reference on the netns. However, it doesn't release references to the netns that a netdev cached in dst_cache might be taking, so the netns still might fail to exit. Since the socket is gimped anyway, we can simply clear all the dst_caches (by way of clearing the endpoint src), which will release all references. However, the current dst_cache_reset function only releases those references lazily. But it turns out that all of our usages of wg_socket_clear_peer_endpoint_src are called from contexts that are not exactly high-speed or bottle-necked. For example, when there's connection difficulty, or when userspace is reconfiguring the interface. And in particular for this patch, when the netns is exiting. So for those cases, it makes more sense to call dst_release immediately. For that, we add a small helper function to dst_cache. This patch also adds a test to netns.sh from Hangbin Liu to ensure this doesn't regress. Tested-by: Hangbin Liu Reported-by: Xiumei Mu Cc: Toke Høiland-Jørgensen Cc: Paolo Abeni Fixes: 900575aa33a3 ("wireguard: device: avoid circular netns references") Signed-off-by: Jason A. Donenfeld Signed-off-by: Jakub Kicinski

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152

2019-05-30T18:26:32+00:00

Based on 1 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of the gnu general public license as published by the free software foundation either version 2 of the license or at your option any later version extracted by the scancode license scanner the SPDX license identifier GPL-2.0-or-later has been chosen to replace the boilerplate/reference in 3029 file(s). Signed-off-by: Thomas Gleixner Reviewed-by: Allison Randal Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190527070032.746973796@linutronix.de Signed-off-by: Greg Kroah-Hartman

net: core: dst_cache_set_ip6: Rename 'addr' parameter to 'saddr' for consistency

2018-03-05T17:52:45+00:00

The other dst_cache_{get,set}_ip{4,6} functions, and the doc comment for dst_cache_set_ip6 use 'saddr' for their source address parameter. Rename the parameter to increase consistency. This fixes the following kernel-doc warnings: ./include/net/dst_cache.h:58: warning: Function parameter or member 'addr' not described in 'dst_cache_set_ip6' ./include/net/dst_cache.h:58: warning: Excess function parameter 'saddr' description in 'dst_cache_set_ip6' Fixes: 911362c70df5 ("net: add dst_cache support") Signed-off-by: Jonathan Neuschäfer Signed-off-by: David S. Miller