asm/unaligned.h is always an include of asm-generic/unaligned.h;
might as well move that thing to linux/unaligned.h and include
that - there's nothing arch-specific in that header.
auto-generated by the following:
for i in `git grep -l -w asm/unaligned.h`; do
sed -i -e "s/asm\/unaligned.h/linux\/unaligned.h/" $i
done
for i in `git grep -l -w asm-generic/unaligned.h`; do
sed -i -e "s/asm-generic\/unaligned.h/linux\/unaligned.h/" $i
done
git mv include/asm-generic/unaligned.h include/linux/unaligned.h
git mv tools/include/asm-generic/unaligned.h tools/include/linux/unaligned.h
sed -i -e "/unaligned.h/d" include/asm-generic/Kbuild
sed -i -e "s/__ASM_GENERIC/__LINUX/" include/linux/unaligned.h tools/include/linux/unaligned.h
err varibale will be set everytime,like -ENOBUFS and in if (err < 0),
when code gets into this path. This check will just slowdown
the execution and that's all.
Signed-off-by: Xi Huang <xuiagnh@gmail.com>
Reviewed-by: Florian Westphal <fw@strlen.de>
Link: https://patch.msgid.link/20240820115442.49366-1-xuiagnh@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
INFINITY_LIFE_TIME is the common value used in IPv4 and IPv6 but defined
in both .c files.
Also, 0xffffffff used in addrconf_timeout_fixup() is INFINITY_LIFE_TIME.
Let's move INFINITY_LIFE_TIME's definition to addrconf.h
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Link: https://patch.msgid.link/20240809235406.50187-6-kuniyu@amazon.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
draft-ietf-6man-pio-pflag is adding a new flag to the Prefix Information
Option to signal that the network can allocate a unique IPv6 prefix per
client via DHCPv6-PD (see draft-ietf-v6ops-dhcp-pd-per-device).
When ra_honor_pio_pflag is enabled, the presence of a P-flag causes
SLAAC autoconfiguration to be disabled for that particular PIO.
An automated test has been added in Android (r.android.com/3195335) to
go along with this change.
Cc: Maciej Żenczykowski <maze@google.com>
Cc: Lorenzo Colitti <lorenzo@google.com>
Cc: David Lamparter <equinox@opensourcerouting.org>
Cc: Simon Horman <horms@kernel.org>
Signed-off-by: Patrick Rohr <prohr@google.com>
Reviewed-by: Maciej Żenczykowski <maze@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
const qualify the struct ctl_table argument in the proc_handler function
signatures. This is a prerequisite to moving the static ctl_table
structs into .rodata data which will ensure that proc_handler function
pointers cannot be modified.
This patch has been generated by the following coccinelle script:
```
virtual patch
@r1@
identifier ctl, write, buffer, lenp, ppos;
identifier func !~ "appldata_(timer|interval)_handler|sched_(rt|rr)_handler|rds_tcp_skbuf_handler|proc_sctp_do_(hmac_alg|rto_min|rto_max|udp_port|alpha_beta|auth|probe_interval)";
@@
int func(
- struct ctl_table *ctl
+ const struct ctl_table *ctl
,int write, void *buffer, size_t *lenp, loff_t *ppos);
@r2@
identifier func, ctl, write, buffer, lenp, ppos;
@@
int func(
- struct ctl_table *ctl
+ const struct ctl_table *ctl
,int write, void *buffer, size_t *lenp, loff_t *ppos)
{ ... }
@r3@
identifier func;
@@
int func(
- struct ctl_table *
+ const struct ctl_table *
,int , void *, size_t *, loff_t *);
@r4@
identifier func, ctl;
@@
int func(
- struct ctl_table *ctl
+ const struct ctl_table *ctl
,int , void *, size_t *, loff_t *);
@r5@
identifier func, write, buffer, lenp, ppos;
@@
int func(
- struct ctl_table *
+ const struct ctl_table *
,int write, void *buffer, size_t *lenp, loff_t *ppos);
```
* Code formatting was adjusted in xfs_sysctl.c to comply with code
conventions. The xfs_stats_clear_proc_handler,
xfs_panic_mask_proc_handler and xfs_deprecated_dointvec_minmax where
adjusted.
* The ctl_table argument in proc_watchdog_common was const qualified.
This is called from a proc_handler itself and is calling back into
another proc_handler, making it necessary to change it as part of the
proc_handler migration.
Co-developed-by: Thomas Weißschuh <linux@weissschuh.net>
Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Co-developed-by: Joel Granados <j.granados@samsung.com>
Signed-off-by: Joel Granados <j.granados@samsung.com>
Merge in late fixes to prepare for the 6.11 net-next PR.
Conflicts:
93c3a96c30 ("net: pse-pd: Do not return EOPNOSUPP if config is null")
4cddb0f15e ("net: ethtool: pse-pd: Fix possible null-deref")
30d7b67277 ("net: ethtool: Add new power limit get and set features")
https://lore.kernel.org/20240715123204.623520bb@canb.auug.org.au/
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
When the source address is selected, the scope must be checked. For
example, if a loopback address is assigned to the vrf device, it must not
be chosen for packets sent outside.
CC: stable@vger.kernel.org
Fixes: afbac6010a ("net: ipv6: Address selection needs to consider L3 domains")
Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Link: https://patch.msgid.link/20240710081521.3809742-4-nicolas.dichtel@6wind.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
The sysctl core is preparing to only expose instances of
struct ctl_table as "const".
This will also affect the ctl_table argument of sysctl handlers.
As the function prototype of all sysctl handlers throughout the tree
needs to stay consistent that change will be done in one commit.
To reduce the size of that final commit, switch utility functions which
are not bound by "typedef proc_handler" to "const struct ctl_table".
No functional change.
Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Link: https://lore.kernel.org/r/20240527-sysctl-const-handler-net-v1-3-16523767d0b2@weissschuh.net
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
This commit comes at the tail end of a greater effort to remove the
empty elements at the end of the ctl_table arrays (sentinels) which
will reduce the overall build time size of the kernel and run time
memory bloat by ~64 bytes per sentinel (further information Link :
https://lore.kernel.org/all/ZO5Yx5JFogGi%2FcBo@bombadil.infradead.org/)
* Remove sentinel element from ctl_table structs.
* Remove the zeroing out of an array element (to make it look like a
sentinel) in sysctl_route_net_init And ipv6_route_sysctl_init.
This is not longer needed and is safe after commit c899710fe7
("networking: Update to register_net_sysctl_sz") added the array size
to the ctl_table registration.
* Remove extra sentinel element in the declaration of devinet_vars.
* Removed the "-1" in __devinet_sysctl_register, sysctl_route_net_init,
ipv6_sysctl_net_init and ipv4_sysctl_init_net that adjusted for having
an extra empty element when looping over ctl_table arrays
* Replace the for loop stop condition in __addrconf_sysctl_register that
tests for procname == NULL with one that depends on array size
* Removing the unprivileged user check in ipv6_route_sysctl_init is
safe as it is replaced by calling ipv6_route_sysctl_table_size;
introduced in commit c899710fe7 ("networking: Update to
register_net_sysctl_sz")
* Use a table_size variable to keep the value of ARRAY_SIZE
Signed-off-by: Joel Granados <j.granados@samsung.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
To be able to constify instances of struct ctl_tables it is necessary to
remove ways through which non-const versions are exposed from the
sysctl core.
One of these is the ctl_table_arg member of struct ctl_table_header.
Constify this reference as a prerequisite for the full constification of
struct ctl_table instances.
No functional change.
Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Unlike IPv6 tunnels which use purely-kernel __ip6_tnl_parm structure
to store params inside the kernel, IPv4 tunnel code uses the same
ip_tunnel_parm which is being used to talk with the userspace.
This makes it difficult to alter or add any fields or use a
different format for whatever data.
Define struct ip_tunnel_parm_kern, a 1:1 copy of ip_tunnel_parm for
now, and use it throughout the code. Define the pieces, where the copy
user <-> kernel happens, as standalone functions, and copy the data
there field-by-field, so that the kernel-side structure could be easily
modified later on and the users wouldn't have to care about this.
Reviewed-by: Simon Horman <horms@kernel.org>
Signed-off-by: Alexander Lobakin <aleksander.lobakin@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Cited commit started returning an error when user space requests to dump
the interface's IPv6 addresses and IPv6 is disabled on the interface.
Restore the previous behavior and do not return an error.
Before cited commit:
# ip address show dev dummy1
2: dummy1: <BROADCAST,NOARP,UP,LOWER_UP> mtu 1500 qdisc noqueue state UNKNOWN group default qlen 1000
link/ether 1a:52:02:5a:c2:6e brd ff:ff:ff:ff:ff:ff
inet6 fe80::1852:2ff:fe5a:c26e/64 scope link proto kernel_ll
valid_lft forever preferred_lft forever
# ip link set dev dummy1 mtu 1000
# ip address show dev dummy1
2: dummy1: <BROADCAST,NOARP,UP,LOWER_UP> mtu 1000 qdisc noqueue state UNKNOWN group default qlen 1000
link/ether 1a:52:02:5a:c2:6e brd ff:ff:ff:ff:ff:ff
After cited commit:
# ip address show dev dummy1
2: dummy1: <BROADCAST,NOARP,UP,LOWER_UP> mtu 1500 qdisc noqueue state UNKNOWN group default qlen 1000
link/ether 1e:9b:94:00:ac:e8 brd ff:ff:ff:ff:ff:ff
inet6 fe80::1c9b:94ff:fe00:ace8/64 scope link proto kernel_ll
valid_lft forever preferred_lft forever
# ip link set dev dummy1 mtu 1000
# ip address show dev dummy1
RTNETLINK answers: No such device
Dump terminated
With this patch:
# ip address show dev dummy1
2: dummy1: <BROADCAST,NOARP,UP,LOWER_UP> mtu 1500 qdisc noqueue state UNKNOWN group default qlen 1000
link/ether 42:35:fc:53:66:cf brd ff:ff:ff:ff:ff:ff
inet6 fe80::4035:fcff:fe53:66cf/64 scope link proto kernel_ll
valid_lft forever preferred_lft forever
# ip link set dev dummy1 mtu 1000
# ip address show dev dummy1
2: dummy1: <BROADCAST,NOARP,UP,LOWER_UP> mtu 1000 qdisc noqueue state UNKNOWN group default qlen 1000
link/ether 42:35:fc:53:66:cf brd ff:ff:ff:ff:ff:ff
Fixes: 9cc4cc329d ("ipv6: use xa_array iterator to implement inet6_dump_addr()")
Reported-by: Gal Pressman <gal@nvidia.com>
Closes: https://lore.kernel.org/netdev/7e261328-42eb-411d-b1b4-ad884eeaae4d@linux.dev/
Tested-by: Gal Pressman <gal@nvidia.com>
Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://lore.kernel.org/r/20240321173042.2151756-1-idosch@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
We can now remove RTNL acquisition while running
inet6_dump_addr(), inet6_dump_ifmcaddr()
and inet6_dump_ifacaddr().
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
inet6_dump_addr() can use the new xa_array iterator
for better scalability.
Make it ready for RCU-only protection.
RTNL use is removed in the following patch.
Also properly return 0 at the end of a dump to avoid
and extra recvmsg() to get NLMSG_DONE.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
in6_dump_addrs() is called with RCU protection.
There is no need holding idev->lock to iterate through unicast addresses.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Make inet6_fill_ifaddr() lockless, and add approriate annotations
on ifa->tstamp, ifa->valid_lft, ifa->preferred_lft, ifa->ifa_proto
and ifa->rt_priority.
Also constify 2nd argument of inet6_fill_ifaddr(), inet6_fill_ifmcaddr()
and inet6_fill_ifacaddr().
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
After commit b5a899154a ("netlink: handle EMSGSIZE errors
in the core"), we can remove some code that was not 100 % correct
anyway.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Link: https://lore.kernel.org/r/20240306102426.245689-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
1) inet6_netconf_dump_devconf() can run under RCU protection
instead of RTNL.
2) properly return 0 at the end of a dump, avoiding an
an extra recvmsg() system call.
3) Do not use inet6_base_seq() anymore, for_each_netdev_dump()
has nice properties. Restarting a GETDEVCONF dump if a device has
been added/removed or if net->ipv6.dev_addr_genid has changed is moot.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Jiri Pirko <jiri@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Writing over /proc/sys/net/ipv6/conf/default/disable_policy
does not need to hold RTNL.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Jiri Pirko <jiri@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
idev->cnf.disable_policy and net->ipv6.devconf_all->disable_policy
can be read locklessly. Add appropriate annotations on reads
and writes.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Jiri Pirko <jiri@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
devconf->proxy_ndp can be read and written locklessly,
add appropriate annotations.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Jiri Pirko <jiri@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
idev->cnf.ignore_routes_with_linkdown can be used without any locks,
add appropriate annotations.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Jiri Pirko <jiri@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
idev->cnf.forwarding and net->ipv6.devconf_all->forwarding
might be read locklessly, add appropriate READ_ONCE()
and WRITE_ONCE() annotations.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Jiri Pirko <jiri@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
idev->cnf.mtu6 might be read locklessly, add appropriate READ_ONCE()
and WRITE_ONCE() annotations.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Jiri Pirko <jiri@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Writing over /proc/sys/net/ipv6/conf/default/disable_ipv6
does not need to hold RTNL.
v3: remove a wrong change (Jakub Kicinski feedback)
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Jiri Pirko <jiri@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
disable_ipv6 is read locklessly, add appropriate READ_ONCE()
and WRITE_ONCE() annotations.
v2: do not preload net before rtnl_trylock() in
addrconf_disable_ipv6() (Jiri)
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Jiri Pirko <jiri@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
I missed that inet6_dump_addr() is calling in6_dump_addrs()
from two points.
First one under RTNL protection, and second one under rcu_read_lock().
Since we want to remove RTNL use from inet6_dump_addr() very soon,
no longer assume in6_dump_addrs() is protected by RTNL (even
if this is still the case).
Use rcu_read_lock() earlier to fix this lockdep splat:
WARNING: suspicious RCU usage
6.8.0-rc5-syzkaller-01618-gf8cbf6bde4c8 #0 Not tainted
net/ipv6/addrconf.c:5317 suspicious rcu_dereference_check() usage!
other info that might help us debug this:
rcu_scheduler_active = 2, debug_locks = 1
3 locks held by syz-executor.2/8834:
#0: ffff88802f554678 (nlk_cb_mutex-ROUTE){+.+.}-{3:3}, at: __netlink_dump_start+0x119/0x780 net/netlink/af_netlink.c:2338
#1: ffffffff8f377a88 (rtnl_mutex){+.+.}-{3:3}, at: netlink_dump+0x676/0xda0 net/netlink/af_netlink.c:2265
#2: ffff88807e5f0580 (&ndev->lock){++--}-{2:2}, at: in6_dump_addrs+0xb8/0x1de0 net/ipv6/addrconf.c:5279
stack backtrace:
CPU: 1 PID: 8834 Comm: syz-executor.2 Not tainted 6.8.0-rc5-syzkaller-01618-gf8cbf6bde4c8 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/25/2024
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0x1e7/0x2e0 lib/dump_stack.c:106
lockdep_rcu_suspicious+0x220/0x340 kernel/locking/lockdep.c:6712
in6_dump_addrs+0x1b47/0x1de0 net/ipv6/addrconf.c:5317
inet6_dump_addr+0x1597/0x1690 net/ipv6/addrconf.c:5428
netlink_dump+0x6a6/0xda0 net/netlink/af_netlink.c:2266
__netlink_dump_start+0x59d/0x780 net/netlink/af_netlink.c:2374
netlink_dump_start include/linux/netlink.h:340 [inline]
rtnetlink_rcv_msg+0xcf7/0x10d0 net/core/rtnetlink.c:6555
netlink_rcv_skb+0x1e3/0x430 net/netlink/af_netlink.c:2547
netlink_unicast_kernel net/netlink/af_netlink.c:1335 [inline]
netlink_unicast+0x7ea/0x980 net/netlink/af_netlink.c:1361
netlink_sendmsg+0x8e0/0xcb0 net/netlink/af_netlink.c:1902
sock_sendmsg_nosec net/socket.c:730 [inline]
__sock_sendmsg+0x221/0x270 net/socket.c:745
____sys_sendmsg+0x525/0x7d0 net/socket.c:2584
___sys_sendmsg net/socket.c:2638 [inline]
__sys_sendmsg+0x2b0/0x3a0 net/socket.c:2667
Fixes: c3718936ec ("ipv6: anycast: complete RCU handling of struct ifacaddr6")
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Jiri Pirko <jiri@nvidia.com>
Link: https://lore.kernel.org/r/20240227222259.4081489-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
struct ifacaddr6 are already freed after RCU grace period.
Add __rcu qualifier to aca_next pointer, and idev->ac_list
Add relevant rcu_assign_pointer() and dereference accessors.
ipv6_chk_acast_dev() no longer needs to acquire idev->lock.
/proc/net/anycast6 is now purely RCU protected, it no
longer acquires idev->lock.
Similarly in6_dump_addrs() can use RCU protection to iterate
through anycast addresses. It was relying on a mixture of RCU
and RTNL but next patches will get rid of RTNL there.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Jiri Pirko <jiri@nvidia.com>
Link: https://lore.kernel.org/r/20240223201054.220534-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
It seems that if userspace provides a correct IFA_TARGET_NETNSID value
but no IFA_ADDRESS and IFA_LOCAL attributes, inet6_rtm_getaddr()
returns -EINVAL with an elevated "struct net" refcount.
Fixes: 6ecf4c37eb ("ipv6: enable IFA_TARGET_NETNSID for RTM_GETADDR")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Christian Brauner <brauner@kernel.org>
Cc: David Ahern <dsahern@kernel.org>
Reviewed-by: David Ahern <dsahern@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
No longer hold RTNL while calling inet6_dump_ifinfo()
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Donald Hunter <donald.hunter@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Prepare inet6_dump_ifinfo() to run with RCU protection
instead of RTNL and use for_each_netdev_dump() interface.
Also properly return 0 at the end of a dump, avoiding
an extra recvmsg() system call and RTNL acquisition.
Note that RTNL-less dumps need core changes, coming later
in the series.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Reviewed-by: Donald Hunter <donald.hunter@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
We want to use RCU protection instead of RTNL
for inet6_fill_ifinfo().
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
We want to no longer hold RTNL while calling inet6_fill_ifla6_attrs()
in the future. Add needed READ_ONCE()/WRITE_ONCE() annotations.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Donald Hunter <donald.hunter@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
net->dev_base_seq and ipv6.dev_addr_genid are monotonically increasing.
If we XOR their values, we could miss to detect if both values
were changed with the same amount.
Fixes: 63998ac24f ("ipv6: provide addr and netconf dump consistency info")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
If the preferred lifetime was less than the minimum required lifetime,
ipv6_create_tempaddr would error out without creating any new address.
On my machine and network, this error happened immediately with the
preferred lifetime set to 5 seconds or less, after a few minutes with
the preferred lifetime set to 6 seconds, and not at all with the
preferred lifetime set to 7 seconds. During my investigation, I found a
Stack Exchange post from another person who seems to have had the same
problem: They stopped getting new addresses if they lowered the
preferred lifetime below 3 seconds, and they didn't really know why.
The preferred lifetime is a preference, not a hard requirement. The
kernel does not strictly forbid new connections on a deprecated address,
nor does it guarantee that the address will be disposed of the instant
its total valid lifetime expires. So rather than disable IPv6 privacy
extensions altogether if the minimum required lifetime swells above the
preferred lifetime, it is more in keeping with the user's intent to
increase the temporary address's lifetime to the minimum necessary for
the current network conditions.
With these fixes, setting the preferred lifetime to 5 or 6 seconds "just
works" because the extra fraction of a second is practically
unnoticeable. It's even possible to reduce the time before deprecation
to 1 or 2 seconds by setting /proc/sys/net/ipv6/conf/*/regen_min_advance
and /proc/sys/net/ipv6/conf/*/dad_transmits to 0. I realize that that is
a pretty niche use case, but I know at least one person who would gladly
sacrifice performance and convenience to be sure that they are getting
the maximum possible level of privacy.
Link: https://serverfault.com/a/1031168/310447
Signed-off-by: Alex Henrie <alexhenrie24@gmail.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
In RFC 8981, REGEN_ADVANCE cannot be less than 2 seconds, and the RFC
does not permit the creation of temporary addresses with lifetimes
shorter than that:
> When processing a Router Advertisement with a
> Prefix Information option carrying a prefix for the purposes of
> address autoconfiguration (i.e., the A bit is set), the host MUST
> perform the following steps:
> 5. A temporary address is created only if this calculated preferred
> lifetime is greater than REGEN_ADVANCE time units.
However, some users want to change their IPv6 address as frequently as
possible regardless of the RFC's arbitrary minimum lifetime. For the
benefit of those users, add a regen_min_advance sysctl parameter that
can be set to below or above 2 seconds.
Link: https://datatracker.ietf.org/doc/html/rfc8981
Signed-off-by: Alex Henrie <alexhenrie24@gmail.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
RFC 8981 defines REGEN_ADVANCE as follows:
REGEN_ADVANCE = 2 + (TEMP_IDGEN_RETRIES * DupAddrDetectTransmits * RetransTimer / 1000)
Thus, allowing it to be less than 2 seconds is technically a protocol
violation.
Link: https://datatracker.ietf.org/doc/html/rfc8981#name-defined-protocol-parameters
Signed-off-by: Alex Henrie <alexhenrie24@gmail.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
operstate_show() can omit dev_base_lock acquisition only
to read dev->operstate.
Annotate accesses to dev->operstate.
Writers still acquire dev_base_lock for mutual exclusion.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Make the decision to set or clean the expires of a route based on the
RTF_EXPIRES flag, rather than the value of the "expires" argument.
This patch doesn't make difference logically, but make inet6_addr_modify()
and modify_prefix_route() consistent.
The function inet6_addr_modify() is the only caller of
modify_prefix_route(), and it passes the RTF_EXPIRES flag and an expiration
value. The RTF_EXPIRES flag is turned on or off based on the value of
valid_lft. The RTF_EXPIRES flag is turned on if valid_lft is a finite value
(not infinite, not 0xffffffff). Even if valid_lft is 0, the RTF_EXPIRES
flag remains on. The expiration value being passed is equal to the
valid_lft value if the flag is on. However, if the valid_lft value is
infinite, the expiration value becomes 0 and the RTF_EXPIRES flag is turned
off. Despite this, modify_prefix_route() decides to set the expiration
value if the received expiration value is not zero. This mixing of infinite
and zero cases creates an inconsistency.
Reviewed-by: Hangbin Liu <liuhangbin@gmail.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Signed-off-by: Kui-Feng Lee <thinker.li@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
FIB6 GC walks trees of fib6_tables to remove expired routes. Walking a tree
can be expensive if the number of routes in a table is big, even if most of
them are permanent. Checking routes in a separated list of routes having
expiration will avoid this potential issue.
Reviewed-by: David Ahern <dsahern@kernel.org>
Signed-off-by: Kui-Feng Lee <thinker.li@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Both addrconf_verify_work() and addrconf_dad_work() acquire rtnl,
there is no point trying to have one thread per cpu.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Link: https://lore.kernel.org/r/20240201173031.3654257-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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 <dsahern@kernel.org>
Cc: Lorenzo Colitti <lorenzo@google.com>
Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Signed-off-by: Maciej Żenczykowski <maze@google.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
If the preferred lifetime was less than the minimum required lifetime,
ipv6_create_tempaddr would error out without creating any new address.
On my machine and network, this error happened immediately with the
preferred lifetime set to 1 second, after a few minutes with the
preferred lifetime set to 4 seconds, and not at all with the preferred
lifetime set to 5 seconds. During my investigation, I found a Stack
Exchange post from another person who seems to have had the same
problem: They stopped getting new addresses if they lowered the
preferred lifetime below 3 seconds, and they didn't really know why.
The preferred lifetime is a preference, not a hard requirement. The
kernel does not strictly forbid new connections on a deprecated address,
nor does it guarantee that the address will be disposed of the instant
its total valid lifetime expires. So rather than disable IPv6 privacy
extensions altogether if the minimum required lifetime swells above the
preferred lifetime, it is more in keeping with the user's intent to
increase the temporary address's lifetime to the minimum necessary for
the current network conditions.
With these fixes, setting the preferred lifetime to 3 or 4 seconds "just
works" because the extra fraction of a second is practically
unnoticeable. It's even possible to reduce the time before deprecation
to 1 or 2 seconds by also disabling duplicate address detection (setting
/proc/sys/net/ipv6/conf/*/dad_transmits to 0). I realize that that is a
pretty niche use case, but I know at least one person who would gladly
sacrifice performance and convenience to be sure that they are getting
the maximum possible level of privacy.
Link: https://serverfault.com/a/1031168/310447
Signed-off-by: Alex Henrie <alexhenrie24@gmail.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Link: https://lore.kernel.org/r/20231024212312.299370-3-alexhenrie24@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
