kernel/linux.git/include/net/if_inet6.h, branch v6.6.131

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

2023-12-20T16:01:45+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

2022-04-07T05:09:39+00:00

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

net: Add new protocol attribute to IP addresses

2022-02-19T05:20:06+00:00

This patch adds a new protocol attribute to IPv4 and IPv6 addresses. Inspiration was taken from the protocol attribute of routes. User space applications like iproute2 can set/get the protocol with the Netlink API. The attribute is stored as an 8-bit unsigned integer. The protocol attribute is set by kernel for these categories: - IPv4 and IPv6 loopback addresses - IPv6 addresses generated from router announcements - IPv6 link local addresses User space may pass custom protocols, not defined by the kernel. Grouping addresses on their origin is useful in scenarios where you want to distinguish between addresses based on who added them, e.g. kernel vs. user space. Tagging addresses with a string label is an existing feature that could be used as a solution. Unfortunately the max length of a label is 15 characters, and for compatibility reasons the label must be prefixed with the name of the device followed by a colon. Since device names also have a max length of 15 characters, only -1 characters is guaranteed to be available for any origin tag, which is not that much. A reference implementation of user space setting and getting protocols is available for iproute2: https://github.com/westermo/iproute2/commit/9a6ea18bd79f47f293e5edc7780f315ea42ff540 Signed-off-by: Jacques de Laval Reviewed-by: David Ahern Link: https://lore.kernel.org/r/20220217150202.80802-1-Jacques.De.Laval@westermo.com Signed-off-by: Jakub Kicinski

ipv6: add net device refcount tracker to struct inet6_dev

2021-12-07T00:05:11+00:00

Signed-off-by: Eric Dumazet Signed-off-by: Jakub Kicinski

ipv6: add IFLA_INET6_RA_MTU to expose mtu value

2021-08-28T00:29:18+00:00

The kernel provides a "/proc/sys/net/ipv6/conf//mtu" file, which can temporarily record the mtu value of the last received RA message when the RA mtu value is lower than the interface mtu, but this proc has following limitations: (1) when the interface mtu (/sys/class/net//mtu) is updeated, mtu6 (/proc/sys/net/ipv6/conf//mtu) will be updated to the value of interface mtu; (2) mtu6 (/proc/sys/net/ipv6/conf//mtu) only affect ipv6 connection, and not affect ipv4. Therefore, when the mtu option is carried in the RA message, there will be a problem that the user sometimes cannot obtain RA mtu value correctly by reading mtu6. After this patch set, if a RA message carries the mtu option, you can send a netlink msg which nlmsg_type is RTM_GETLINK, and then by parsing the attribute of IFLA_INET6_RA_MTU to get the mtu value carried in the RA message received on the inet6 device. In addition, you can also get a link notification when ra_mtu is updated so it doesn't have to poll. In this way, if the MTU values that the device receives from the network in the PCO IPv4 and the RA IPv6 procedures are different, the user can obtain the correct ipv6 ra_mtu value and compare the value of ra_mtu and ipv4 mtu, then the device can use the lower MTU value for both IPv4 and IPv6. Signed-off-by: Rocco Yue Reviewed-by: David Ahern Link: https://lore.kernel.org/r/20210827150412.9267-1-rocco.yue@mediatek.com Signed-off-by: Jakub Kicinski

net/ipv6/mcast: Use struct_size() helper

2021-08-05T10:46:42+00:00

Replace IP6_SFLSIZE() with struct_size() helper in order to avoid any potential type mistakes or integer overflows that, in the worst scenario, could lead to heap overflows. Signed-off-by: Gustavo A. R. Silva Signed-off-by: David S. Miller

mld: add mc_lock for protecting per-interface mld data

2021-03-26T22:14:56+00:00

The purpose of this lock is to avoid a bottleneck in the query/report event handler logic. By previous patches, almost all mld data is protected by RTNL. So, the query and report event handler, which is data path logic acquires RTNL too. Therefore if a lot of query and report events are received, it uses RTNL for a long time. So it makes the control-plane bottleneck because of using RTNL. In order to avoid this bottleneck, mc_lock is added. mc_lock protect only per-interface mld data and per-interface mld data is used in the query/report event handler logic. So, no longer rtnl_lock is needed in the query/report event handler logic. Therefore bottleneck will be disappeared by mc_lock. Suggested-by: Cong Wang Signed-off-by: Taehee Yoo Signed-off-by: David S. Miller

mld: add new workqueues for process mld events

2021-03-26T22:14:56+00:00

When query/report packets are received, mld module processes them. But they are processed under BH context so it couldn't use sleepable functions. So, in order to switch context, the two workqueues are added which processes query and report event. In the struct inet6_dev, mc_{query | report}_queue are added so it is per-interface queue. And mc_{query | report}_work are workqueue structure. When the query or report event is received, skb is queued to proper queue and worker function is scheduled immediately. Workqueues and queues are protected by spinlock, which is mc_{query | report}_lock, and worker functions are protected by RTNL. Suggested-by: Cong Wang Signed-off-by: Taehee Yoo Signed-off-by: David S. Miller

mld: convert ifmcaddr6 to RCU

2021-03-26T22:14:56+00:00

The ifmcaddr6 has been protected by inet6_dev->lock(rwlock) so that the critical section is atomic context. In order to switch this context, changing locking is needed. The ifmcaddr6 actually already protected by RTNL So if it's converted to use RCU, its control path context can be switched to sleepable. Suggested-by: Cong Wang Signed-off-by: Taehee Yoo Signed-off-by: David S. Miller

mld: convert ip6_sf_list to RCU

2021-03-26T22:14:56+00:00

The ip6_sf_list has been protected by mca_lock(spin_lock) so that the critical section is atomic context. In order to switch this context, changing locking is needed. The ip6_sf_list actually already protected by RTNL So if it's converted to use RCU, its control path context can be switched to sleepable. But It doesn't remove mca_lock yet because ifmcaddr6 isn't converted to RCU yet. So, It's not fully converted to the sleepable context. Suggested-by: Cong Wang Signed-off-by: Taehee Yoo Signed-off-by: David S. Miller