kernel/linux.git/include/net/if_inet6.h, branch v5.10.257

net: ipv6: support reporting otherwise unknown prefix flags in RTM_NEWPREFIX

2023-12-20T14:44:27+00:00

[ Upstream commit bd4a816752bab609dd6d65ae021387beb9e2ddbd ] Lorenzo points out that we effectively clear all unknown flags from PIO when copying them to userspace in the netlink RTM_NEWPREFIX notification. We could fix this one at a time as new flags are defined, or in one fell swoop - I choose the latter. We could either define 6 new reserved flags (reserved1..6) and handle them individually (and rename them as new flags are defined), or we could simply copy the entire unmodified byte over - I choose the latter. This unfortunately requires some anonymous union/struct magic, so we add a static assert on the struct size for a little extra safety. Cc: David Ahern Cc: Lorenzo Colitti Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Maciej Żenczykowski Reviewed-by: David Ahern Signed-off-by: David S. Miller Signed-off-by: Sasha Levin

ipv6: fix locking issues with loops over idev->addr_list

2022-06-09T08:20:50+00:00

[ Upstream commit 51454ea42c1ab4e0c2828bb0d4d53957976980de ] idev->addr_list needs to be protected by idev->lock. However, it is not always possible to do so while iterating and performing actions on inet6_ifaddr instances. For example, multiple functions (like addrconf_{join,leave}_anycast) eventually call down to other functions that acquire the idev->lock. The current code temporarily unlocked the idev->lock during the loops, which can cause race conditions. Moving the locks up is also not an appropriate solution as the ordering of lock acquisition will be inconsistent with for example mc_lock. This solution adds an additional field to inet6_ifaddr that is used to temporarily add the instances to a temporary list while holding idev->lock. The temporary list can then be traversed without holding idev->lock. This change was done in two places. In addrconf_ifdown, the list_for_each_entry_safe variant of the list loop is also no longer necessary as there is no deletion within that specific loop. Suggested-by: Paolo Abeni Signed-off-by: Niels Dossche Acked-by: Paolo Abeni Link: https://lore.kernel.org/r/20220403231523.45843-1-dossche.niels@gmail.com Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin

ipv6: Replace zero-length array with flexible-array

2020-05-11T20:18:54+00:00

The current codebase makes use of the zero-length array language extension to the C90 standard, but the preferred mechanism to declare variable-length types such as these ones is a flexible array member[1][2], introduced in C99: struct foo { int stuff; struct boo array[]; }; By making use of the mechanism above, we will get a compiler warning in case the flexible array does not occur last in the structure, which will help us prevent some kind of undefined behavior bugs from being inadvertently introduced[3] to the codebase from now on. Also, notice that, dynamic memory allocations won't be affected by this change: "Flexible array members have incomplete type, and so the sizeof operator may not be applied. As a quirk of the original implementation of zero-length arrays, sizeof evaluates to zero."[1] sizeof(flexible-array-member) triggers a warning because flexible array members have incomplete type[1]. There are some instances of code in which the sizeof operator is being incorrectly/erroneously applied to zero-length arrays and the result is zero. Such instances may be hiding some bugs. So, this work (flexible-array member conversions) will also help to get completely rid of those sorts of issues. This issue was found with the help of Coccinelle. [1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html [2] https://github.com/KSPP/linux/issues/21 [3] commit 76497732932f ("cxgb3/l2t: Fix undefined behaviour") Signed-off-by: Gustavo A. R. Silva Signed-off-by: David S. Miller

ipv6: Implement draft-ietf-6man-rfc4941bis

2020-05-07T00:00:02+00:00

Implement the upcoming rev of RFC4941 (IPv6 temporary addresses): https://tools.ietf.org/html/draft-ietf-6man-rfc4941bis-09 * Reduces the default Valid Lifetime to 2 days The number of extra addresses employed when Valid Lifetime was 7 days exacerbated the stress caused on network elements/devices. Additionally, the motivation for temporary addresses is indeed privacy and reduced exposure. With a default Valid Lifetime of 7 days, an address that becomes revealed by active communication is reachable and exposed for one whole week. The only use case for a Valid Lifetime of 7 days could be some application that is expecting to have long lived connections. But if you want to have a long lived connections, you shouldn't be using a temporary address in the first place. Additionally, in the era of mobile devices, general applications should nevertheless be prepared and robust to address changes (e.g. nodes swap wifi <-> 4G, etc.) * Employs different IIDs for different prefixes To avoid network activity correlation among addresses configured for different prefixes * Uses a simpler algorithm for IID generation No need to store "history" anywhere Signed-off-by: Fernando Gont Signed-off-by: David S. Miller

ipv6: shrink struct ipv6_mc_socklist

2019-08-28T21:43:03+00:00

Remove two holes on 64bit arches, to bring the size to one cache line exactly. Signed-off-by: Eric Dumazet Signed-off-by: David S. Miller

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/ipv6: Add anycast addresses to a global hashtable

2018-11-03T06:54:56+00:00

icmp6_send() function is expensive on systems with a large number of interfaces. Every time it’s called, it has to verify that the source address does not correspond to an existing anycast address by looping through every device and every anycast address on the device. This can result in significant delays for a CPU when there are a large number of neighbors and ND timers are frequently timing out and calling neigh_invalidate(). Add anycast addresses to a global hashtable to allow quick searching for matching anycast addresses. This is based on inet6_addr_lst in addrconf.c. Signed-off-by: Jeff Barnhill <0xeffeff@gmail.com> Signed-off-by: David S. Miller

net/ipv6: Add support for specifying metric of connected routes

2018-05-29T14:12:45+00:00

Add support for IFA_RT_PRIORITY to ipv6 addresses. If the metric is changed on an existing address then the new route is inserted before removing the old one. Since the metric is one of the route keys, the prefix route can not be atomically replaced. Signed-off-by: David Ahern Signed-off-by: David S. Miller

net/ipv6: Remove aca_idev

2018-04-19T19:40:13+00:00

aca_idev has only 1 user - inet6_fill_ifacaddr - and it only wants the device index which can be extracted from the fib6_info nexthop. Signed-off-by: David Ahern Signed-off-by: David S. Miller

net/ipv6: Flip FIB entries to fib6_info

2018-04-18T03:41:18+00:00

Convert all code paths referencing a FIB entry from rt6_info to fib6_info. Signed-off-by: David Ahern Signed-off-by: David S. Miller