Currently, ip6_tnl_xmit_ctl drops tunneled packets if the remote
address (outer v6 destination) is one of host's locally configured
addresses.
Same applies to ip6_tnl_rcv_ctl: it drops packets if the remote address
(outer v6 source) is a local address.
This prevents using ipxip6 (and ip6_gre) tunnels whose local/remote
endpoints are on same host; OTOH v4 tunnels (ipip or gre) allow such
configurations.
An example where this proves useful is a system where entities are
identified by their unique v6 addresses, and use tunnels to encapsulate
traffic between them. The limitation prevents placing several entities
on same host.
Introduce IP6_TNL_F_ALLOW_LOCAL_REMOTE which allows to bypass this
restriction.
Signed-off-by: Shmulik Ladkani <shmulik.ladkani@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
In rt6_select(), fn->leaf could be pointing to net->ipv6.ip6_null_entry.
In this case, we should directly return instead of trying to carry on
with the rest of the process.
If not, we could crash at:
spin_lock_bh(&leaf->rt6i_table->rt6_lock);
because net->ipv6.ip6_null_entry does not have rt6i_table set.
Syzkaller recently reported following issue on net-next:
Use struct sctp_sack_info instead
kasan: CONFIG_KASAN_INLINE enabled
kasan: GPF could be caused by NULL-ptr deref or user memory access
general protection fault: 0000 [#1] SMP KASAN
Dumping ftrace buffer:
(ftrace buffer empty)
Modules linked in:
sctp: [Deprecated]: syz-executor4 (pid 26496) Use of struct sctp_assoc_value in delayed_ack socket option.
Use struct sctp_sack_info instead
CPU: 1 PID: 26523 Comm: syz-executor6 Not tainted 4.14.0-rc4+ #85
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
task: ffff8801d147e3c0 task.stack: ffff8801a4328000
RIP: 0010:debug_spin_lock_before kernel/locking/spinlock_debug.c:83 [inline]
RIP: 0010:do_raw_spin_lock+0x23/0x1e0 kernel/locking/spinlock_debug.c:112
RSP: 0018:ffff8801a432ed70 EFLAGS: 00010207
RAX: dffffc0000000000 RBX: 0000000000000018 RCX: 0000000000000000
RDX: 0000000000000003 RSI: 0000000000000000 RDI: 000000000000001c
RBP: ffff8801a432ed90 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000000 R11: ffffffff8482b279 R12: ffff8801ce2ff3a0
sctp: [Deprecated]: syz-executor1 (pid 26546) Use of int in maxseg socket option.
Use struct sctp_assoc_value instead
R13: dffffc0000000000 R14: ffff8801d971e000 R15: ffff8801ce2ff0d8
FS: 00007f56e82f5700(0000) GS:ffff8801db300000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001ddbc22000 CR3: 00000001a4a04000 CR4: 00000000001406e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
__raw_spin_lock_bh include/linux/spinlock_api_smp.h:136 [inline]
_raw_spin_lock_bh+0x39/0x40 kernel/locking/spinlock.c:175
spin_lock_bh include/linux/spinlock.h:321 [inline]
rt6_select net/ipv6/route.c:786 [inline]
ip6_pol_route+0x1be3/0x3bd0 net/ipv6/route.c:1650
sctp: [Deprecated]: syz-executor1 (pid 26576) Use of int in maxseg socket option.
Use struct sctp_assoc_value instead
TCP: request_sock_TCPv6: Possible SYN flooding on port 20002. Sending cookies. Check SNMP counters.
ip6_pol_route_output+0x4c/0x60 net/ipv6/route.c:1843
fib6_rule_lookup+0x9e/0x2a0 net/ipv6/ip6_fib.c:309
ip6_route_output_flags+0x1f1/0x2b0 net/ipv6/route.c:1871
ip6_route_output include/net/ip6_route.h:80 [inline]
ip6_dst_lookup_tail+0x4ea/0x970 net/ipv6/ip6_output.c:953
ip6_dst_lookup_flow+0xc8/0x270 net/ipv6/ip6_output.c:1076
sctp_v6_get_dst+0x675/0x1c30 net/sctp/ipv6.c:274
sctp_transport_route+0xa8/0x430 net/sctp/transport.c:287
sctp_assoc_add_peer+0x4fe/0x1100 net/sctp/associola.c:656
__sctp_connect+0x251/0xc80 net/sctp/socket.c:1187
sctp_connect+0xb4/0xf0 net/sctp/socket.c:4209
inet_dgram_connect+0x16b/0x1f0 net/ipv4/af_inet.c:541
SYSC_connect+0x20a/0x480 net/socket.c:1642
SyS_connect+0x24/0x30 net/socket.c:1623
entry_SYSCALL_64_fastpath+0x1f/0xbe
Fixes: 66f5d6ce53 ("ipv6: replace rwlock with rcu and spinlock in fib6_table")
Signed-off-by: Wei Wang <weiwan@google.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
rcu_read_lock() is enough here, no need to block BH.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Table is really RCU protected, no need to block BH
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
rcu_read_lock() is enough here, no need to block BH.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
rcu_read_lock() is enough here, as inet6_ifa_finish_destroy()
uses kfree_rcu()
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Bring IPv6 in par with IPv4 :
- Use net_hash_mix() to spread addresses a bit more.
- Use 256 slots hash table instead of 16
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
ipv6_add_addr_hash() can compute the hash value outside of
locked section and pass it to ipv6_chk_same_addr().
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
ipv6_chk_same_addr() is only used by ipv6_add_addr_hash(),
so moving it avoids a forward declaration.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
New tracepoint trace_tcp_send_reset is added and called from
tcp_v4_send_reset(), tcp_v6_send_reset() and tcp_send_active_reset().
Signed-off-by: Song Liu <songliubraving@fb.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
There were quite a few overlapping sets of changes here.
Daniel's bug fix for off-by-ones in the new BPF branch instructions,
along with the added allowances for "data_end > ptr + x" forms
collided with the metadata additions.
Along with those three changes came veritifer test cases, which in
their final form I tried to group together properly. If I had just
trimmed GIT's conflict tags as-is, this would have split up the
meta tests unnecessarily.
In the socketmap code, a set of preemption disabling changes
overlapped with the rename of bpf_compute_data_end() to
bpf_compute_data_pointers().
Changes were made to the mv88e6060.c driver set addr method
which got removed in net-next.
The hyperv transport socket layer had a locking change in 'net'
which overlapped with a change of socket state macro usage
in 'net-next'.
Signed-off-by: David S. Miller <davem@davemloft.net>
When syzkaller team brought us a C repro for the crash [1] that
had been reported many times in the past, I finally could find
the root cause.
If FlowLabel info is merged by fl6_merge_options(), we leave
part of the opt_space storage provided by udp/raw/l2tp with random value
in opt_space.tot_len, unless a control message was provided at sendmsg()
time.
Then ip6_setup_cork() would use this random value to perform a kzalloc()
call. Undefined behavior and crashes.
Fix is to properly set tot_len in fl6_merge_options()
At the same time, we can also avoid consuming memory and cpu cycles
to clear it, if every option is copied via a kmemdup(). This is the
change in ip6_setup_cork().
[1]
kasan: CONFIG_KASAN_INLINE enabled
kasan: GPF could be caused by NULL-ptr deref or user memory access
general protection fault: 0000 [#1] SMP KASAN
Dumping ftrace buffer:
(ftrace buffer empty)
Modules linked in:
CPU: 0 PID: 6613 Comm: syz-executor0 Not tainted 4.14.0-rc4+ #127
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
task: ffff8801cb64a100 task.stack: ffff8801cc350000
RIP: 0010:ip6_setup_cork+0x274/0x15c0 net/ipv6/ip6_output.c:1168
RSP: 0018:ffff8801cc357550 EFLAGS: 00010203
RAX: dffffc0000000000 RBX: ffff8801cc357748 RCX: 0000000000000010
RDX: 0000000000000002 RSI: ffffffff842bd1d9 RDI: 0000000000000014
RBP: ffff8801cc357620 R08: ffff8801cb17f380 R09: ffff8801cc357b10
R10: ffff8801cb64a100 R11: 0000000000000000 R12: ffff8801cc357ab0
R13: ffff8801cc357b10 R14: 0000000000000000 R15: ffff8801c3bbf0c0
FS: 00007f9c5c459700(0000) GS:ffff8801db200000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000020324000 CR3: 00000001d1cf2000 CR4: 00000000001406f0
DR0: 0000000020001010 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
ip6_make_skb+0x282/0x530 net/ipv6/ip6_output.c:1729
udpv6_sendmsg+0x2769/0x3380 net/ipv6/udp.c:1340
inet_sendmsg+0x11f/0x5e0 net/ipv4/af_inet.c:762
sock_sendmsg_nosec net/socket.c:633 [inline]
sock_sendmsg+0xca/0x110 net/socket.c:643
SYSC_sendto+0x358/0x5a0 net/socket.c:1750
SyS_sendto+0x40/0x50 net/socket.c:1718
entry_SYSCALL_64_fastpath+0x1f/0xbe
RIP: 0033:0x4520a9
RSP: 002b:00007f9c5c458c08 EFLAGS: 00000216 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 0000000000718000 RCX: 00000000004520a9
RDX: 0000000000000001 RSI: 0000000020fd1000 RDI: 0000000000000016
RBP: 0000000000000086 R08: 0000000020e0afe4 R09: 000000000000001c
R10: 0000000000000000 R11: 0000000000000216 R12: 00000000004bb1ee
R13: 00000000ffffffff R14: 0000000000000016 R15: 0000000000000029
Code: e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 ea 0f 00 00 48 8d 79 04 48 b8 00 00 00 00 00 fc ff df 45 8b 74 24 04 48 89 fa 48 c1 ea 03 <0f> b6 14 02 48 89 f8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85
RIP: ip6_setup_cork+0x274/0x15c0 net/ipv6/ip6_output.c:1168 RSP: ffff8801cc357550
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: Dmitry Vyukov <dvyukov@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The perf traces for ipv6 routing code show a relevant cost around
trace_fib6_table_lookup(), even if no trace is enabled. This is
due to the fib6_table de-referencing currently performed by the
caller.
Let's the tracing code pay this overhead, passing to the trace
helper the table pointer. This gives small but measurable
performance improvement under UDP flood.
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Acked-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Acked-by: David Ahern <dsa@cumulusnetworks.com>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The commit 2b760fcf5c ("ipv6: hook up exception table to store
dst cache") partially reverted the commit 1e2ea8ad37 ("ipv6: set
dst.obsolete when a cached route has expired").
As a result, RTF_CACHE dst referenced outside the fib tree will
not be removed until the next sernum change; dst_check() does not
fail on aged-out dst, and dst->__refcnt can't decrease: the aged
out dst will stay valid for a potentially unlimited time after the
timeout expiration.
This change explicitly removes RTF_CACHE dst from the fib tree when
aged out. The rt6_remove_exception() logic will then obsolete the
dst and other entities will drop the related reference on next
dst_check().
pMTU exceptions are not aged-out, and are removed from the exception
table only when the - usually considerably longer - ip6_rt_mtu_expires
timeout expires.
v1 -> v2:
- do not touch dst.obsolete in rt6_remove_exception(), not needed
v2 -> v3:
- take care of pMTU exceptions, too
Fixes: 2b760fcf5c ("ipv6: hook up exception table to store dst cache")
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Acked-by: Wei Wang <weiwan@google.com>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
After the commit 2b760fcf5c ("ipv6: hook up exception table
to store dst cache"), the fib6 gc is not started after the
creation of a RTF_CACHE via a redirect or pmtu update, since
fib6_add() isn't invoked anymore for such dsts.
We need the fib6 gc to run periodically to clean the RTF_CACHE,
or the dst will stay there forever.
Fix it by explicitly calling fib6_force_start_gc() on successful
exception creation. gc_args->more accounting will ensure that
the gc timer will run for whatever time needed to properly
clean the table.
v2 -> v3:
- clarified the commit message
Fixes: 2b760fcf5c ("ipv6: hook up exception table to store dst cache")
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Acked-by: Wei Wang <weiwan@google.com>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add extack to in_validator_info and in6_validator_info. Update the one
user of each, ipvlan, to return an error message for failures.
Only manual configuration of an address is plumbed in the IPv6 code path.
Signed-off-by: David Ahern <dsahern@gmail.com>
Reviewed-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
inet6addr_validator chain was added by commit 3ad7d2468f ("Ipvlan
should return an error when an address is already in use") to allow
address validation before changes are committed and to be able to
fail the address change with an error back to the user. The address
validation is not done for addresses received from router
advertisements.
Handling RAs in softirq context is the only reason for the notifier
chain to be atomic versus blocking. Since the only current user, ipvlan,
of the validator chain ignores softirq context, the notifier can be made
blocking and simply not invoked for softirq path.
The blocking option is needed by spectrum for example to validate
resources for an adding an address to an interface.
Signed-off-by: David Ahern <dsahern@gmail.com>
Reviewed-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
ipv6_add_addr is called in process context with rtnl lock held
(e.g., manual config of an address) or during softirq processing
(e.g., autoconf and address from a router advertisement).
Currently, ipv6_add_addr calls rcu_read_lock_bh shortly after entry
and does not call unlock until exit, minus the call around the address
validator notifier. Similarly, addrconf_hash_lock is taken after the
validator notifier and held until exit. This forces the allocation of
inet6_ifaddr to always be atomic.
Refactor ipv6_add_addr as follows:
1. add an input boolean to discriminate the call path (process context
or softirq). This new flag controls whether the alloc can be done
with GFP_KERNEL or GFP_ATOMIC.
2. Move the rcu_read_lock_bh and unlock calls only around functions that
do rcu updates.
3. Remove the in6_dev_hold and put added by 3ad7d2468f ("Ipvlan should
return an error when an address is already in use."). This was done
presumably because rcu_read_unlock_bh needs to be called before calling
the validator. Since rcu_read_lock is not needed before the validator
runs revert the hold and put added by 3ad7d2468f and only do the
hold when setting ifp->idev.
4. move duplicate address check and insertion of new address in the global
address hash into a helper. The helper is called after an ifa is
allocated and filled in.
This allows the ifa for manually configured addresses to be done with
GFP_KERNEL and reduces the overall amount of time with rcu_read_lock held
and hash table spinlock held.
Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
In preparation to enabling -Wimplicit-fallthrough, mark switch cases
where we are expecting to fall through.
Notice that in some cases I placed the "fall through" comment
on its own line, which is what GCC is expecting to find.
Signed-off-by: Gustavo A. R. Silva <garsilva@embeddedor.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
In preparation for unconditionally passing the struct timer_list pointer to
all timer callbacks, switch to using the new timer_setup() and from_timer()
to pass the timer pointer explicitly.
Cc: Alexander Aring <alex.aring@gmail.com>
Cc: Stefan Schmidt <stefan@osg.samsung.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Alexey Kuznetsov <kuznet@ms2.inr.ac.ru>
Cc: Hideaki YOSHIFUJI <yoshfuji@linux-ipv6.org>
Cc: Pablo Neira Ayuso <pablo@netfilter.org>
Cc: Jozsef Kadlecsik <kadlec@blackhole.kfki.hu>
Cc: Florian Westphal <fw@strlen.de>
Cc: linux-wpan@vger.kernel.org
Cc: netdev@vger.kernel.org
Cc: netfilter-devel@vger.kernel.org
Cc: coreteam@netfilter.org
Signed-off-by: Kees Cook <keescook@chromium.org>
Acked-by: Stefan Schmidt <stefan@osg.samsung.com> # for ieee802154
Signed-off-by: David S. Miller <davem@davemloft.net>
In fib6_locate(), we need to first make sure fn is not NULL before doing
FIB6_SUBTREE(fn) to avoid crash.
This fixes the following static checker warning:
net/ipv6/ip6_fib.c:1462 fib6_locate()
warn: variable dereferenced before check 'fn' (see line 1459)
net/ipv6/ip6_fib.c
1458 if (src_len) {
1459 struct fib6_node *subtree = FIB6_SUBTREE(fn);
^^^^^^^^^^^^^^^^
We shifted this dereference
1460
1461 WARN_ON(saddr == NULL);
1462 if (fn && subtree)
^^
before the check for NULL.
1463 fn = fib6_locate_1(subtree, saddr, src_len,
1464 offsetof(struct rt6_info, rt6i_src)
Fixes: 66f5d6ce53 ("ipv6: replace rwlock with rcu and spinlock in fib6_table")
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Wei Wang <weiwan@google.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Similar to the previous patch, use the device lookup functions
that bump device refcount and flag this as DOIT_UNLOCKED to avoid
rtnl mutex.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
Instead of relying on rtnl mutex bump device reference count.
After this change, values reported can change in parallel, but thats not
much different from current state, as anyone can change the settings
right after rtnl_unlock (and before userspace processed reply).
While at it, switch to GFP_KERNEL allocation.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
The use of the | operator always leads to true which looks rather
suspect to me. Fix this by using & instead to just check the
RTF_CACHE entry bit.
Detected by CoverityScan, CID#1457734, #1457747 ("Wrong operator used")
Fixes: 35732d01fe ("ipv6: introduce a hash table to store dst cache")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Acked-by: Wei Wang <weiwan@google.com>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Currently rt6_ex is being dereferenced before it is null checked
hence there is a possible null dereference bug. Fix this by only
dereferencing rt6_ex after it has been null checked.
Detected by CoverityScan, CID#1457749 ("Dereference before null check")
Fixes: 81eb8447da ("ipv6: take care of rt6_stats")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
After previous patch ("ipv6: addrlabel: rework ip6addrlbl_get()")
we can remove the refcount from struct ip6addrlbl_entry,
since it is no longer elevated in p6addrlbl_get()
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
If we allocate skb before the lookup, we can use RCU
without the need of ip6addrlbl_hold()
This means that the following patch can get rid of refcounting.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Pablo Neira Ayuso says:
====================
Netfilter/IPVS fixes for net
The following patchset contains Netfilter/IPVS fixes for your net tree,
they are:
1) Fix packet drops due to incorrect ECN handling in IPVS, from Vadim
Fedorenko.
2) Fix splat with mark restoration in xt_socket with non-full-sock,
patch from Subash Abhinov Kasiviswanathan.
3) ipset bogusly bails out when adding IPv4 range containing more than
2^31 addresses, from Jozsef Kadlecsik.
4) Incorrect pernet unregistration order in ipset, from Florian Westphal.
5) Races between dump and swap in ipset results in BUG_ON splats, from
Ross Lagerwall.
6) Fix chain renames in nf_tables, from JingPiao Chen.
7) Fix race in pernet codepath with ebtables table registration, from
Artem Savkov.
8) Memory leak in error path in set name allocation in nf_tables, patch
from Arvind Yadav.
9) Don't dump chain counters if they are not available, this fixes a
crash when listing the ruleset.
10) Fix out of bound memory read in strlcpy() in x_tables compat code,
from Eric Dumazet.
11) Make sure we only process TCP packets in SYNPROXY hooks, patch from
Lin Zhang.
12) Cannot load rules incrementally anymore after xt_bpf with pinned
objects, added in revision 1. From Shmulik Ladkani.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
per cpu allocations are already zeroed, no need to clear them again.
Fixes: d52d3997f8 ("ipv6: Create percpu rt6_info")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Martin KaFai Lau <kafai@fb.com>
Cc: Tejun Heo <tj@kernel.org>
Acked-by: Tejun Heo <tj@kernel.org>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
A recent patch removed the dst_free() on the allocated
dst_entry in ipv6_blackhole_route(). The dst_free() marked
the dst_entry as dead and added it to the gc list. I.e. it
was setup for a one time usage. As a result we may now have
a blackhole route cached at a socket on some IPsec scenarios.
This makes the connection unusable.
Fix this by marking the dst_entry directly at allocation time
as 'dead', so it is used only once.
Fixes: 587fea7411 ("ipv6: mark DST_NOGC and remove the operation of dst_free()")
Reported-by: Tobias Brunner <tobias@strongswan.org>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
In function {ipv4,ipv6}_synproxy_hook we expect a normal tcp packet, but
the real server maybe reply an icmp error packet related to the exist
tcp conntrack, so we will access wrong tcp data.
Fix it by checking for the protocol field and only process tcp traffic.
Signed-off-by: Lin Zhang <xiaolou4617@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
By extending the rcu section a bit, we can avoid these
very expensive in6_ifa_put()/in6_ifa_hold() calls
done in __ipv6_dev_get_saddr() and ipv6_dev_get_saddr()
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Callers hold rcu_read_lock(), so we do not need
the rcu_read_lock()/rcu_read_unlock() pair.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
inet6_ifa_finish_destroy() already uses kfree_rcu() to free
inet6_ifaddr structs.
We need to use proper list additions/deletions in order
to allow readers to use RCU instead of idev->lock rwlock.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Ido reported following splat and provided a patch.
[ 122.221814] BUG: using smp_processor_id() in preemptible [00000000] code: sshd/2672
[ 122.221845] caller is debug_smp_processor_id+0x17/0x20
[ 122.221866] CPU: 0 PID: 2672 Comm: sshd Not tainted 4.14.0-rc3-idosch-next-custom #639
[ 122.221880] Hardware name: Mellanox Technologies Ltd. MSN2100-CB2FO/SA001017, BIOS 5.6.5 06/07/2016
[ 122.221893] Call Trace:
[ 122.221919] dump_stack+0xb1/0x10c
[ 122.221946] ? _atomic_dec_and_lock+0x124/0x124
[ 122.221974] ? ___ratelimit+0xfe/0x240
[ 122.222020] check_preemption_disabled+0x173/0x1b0
[ 122.222060] debug_smp_processor_id+0x17/0x20
[ 122.222083] ip6_pol_route+0x1482/0x24a0
...
I believe we can simplify this code path a bit, since we no longer
hold a read_lock and need to release it to avoid a dead lock.
By disabling BH, we make sure we'll prevent code re-entry and
rt6_get_pcpu_route()/rt6_make_pcpu_route() run on the same cpu.
Fixes: 66f5d6ce53 ("ipv6: replace rwlock with rcu and spinlock in fib6_table")
Reported-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Tested-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
When gso_size reset to zero for the tail segment in skb_segment(), later
in ipv6_gso_segment(), __skb_udp_tunnel_segment() and gre_gso_segment()
we will get incorrect results (payload length, pcsum) for that segment.
inet_gso_segment() already has a check for gso_size before calculating
payload.
The issue was found with LTP vxlan & gre tests over ixgbe NIC.
Fixes: 07b26c9454 ("gso: Support partial splitting at the frag_list pointer")
Signed-off-by: Alexey Kodanev <alexey.kodanev@oracle.com>
Acked-by: Alexander Duyck <alexander.h.duyck@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Commit 35e015e1f5 ("ipv6: fix net.ipv6.conf.all interface DAD handlers")
was intended to affect accept_dad flag handling in such a way that
DAD operation and mode on a given interface would be selected
according to the maximum value of conf/{all,interface}/accept_dad.
However, addrconf_dad_begin() checks for particular cases in which we
need to skip DAD, and this check was modified in the wrong way.
Namely, it was modified so that, if the accept_dad flag is 0 for the
given interface *or* for all interfaces, DAD would be skipped.
We have instead to skip DAD if accept_dad is 0 for the given interface
*and* for all interfaces.
Fixes: 35e015e1f5 ("ipv6: fix net.ipv6.conf.all interface DAD handlers")
Acked-by: Stefano Brivio <sbrivio@redhat.com>
Signed-off-by: Matteo Croce <mcroce@redhat.com>
Reported-by: Erik Kline <ek@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Currently, most of the rt6_stats are not hooked up correctly. As the
last part of this patch series, hook up all existing rt6_stats and add
one new stat fib_rt_uncache to indicate the number of routes in the
uncached list.
For details of the stats, please refer to the comments added in
include/net/ip6_fib.h.
Note: fib_rt_alloc and fib_rt_uncache are not guaranteed to be modified
under a lock. So atomic_t is used for them.
Signed-off-by: Wei Wang <weiwan@google.com>
Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
With all the preparation work before, we are now ready to replace rwlock
with rcu and spinlock in fib6_table.
That means now all fib6_node in fib6_table are protected by rcu. And
when freeing fib6_node, call_rcu() is used to wait for the rcu grace
period before releasing the memory.
When accessing fib6_node, corresponding rcu APIs need to be used.
And all previous sessions protected by the write lock will now be
protected by the spin lock per table.
All previous sessions protected by read lock will now be protected by
rcu_read_lock().
A couple of things to note here:
1. As part of the work of replacing rwlock with rcu, the linked list of
fn->leaf now has to be rcu protected as well. So both fn->leaf and
rt->dst.rt6_next are now __rcu tagged and corresponding rcu APIs are
used when manipulating them.
2. For fn->rr_ptr, first of all, it also needs to be rcu protected now
and is tagged with __rcu and rcu APIs are used in corresponding places.
Secondly, fn->rr_ptr is changed in rt6_select() which is a reader
thread. This makes the issue a bit complicated. We think a valid
solution for it is to let rt6_select() grab the tb6_lock if it decides
to change it. As it is not in the normal operation and only happens when
there is no valid neighbor cache for the route, we think the performance
impact should be low.
3. fib6_walk_continue() has to be called with tb6_lock held even in the
route dumping related functions, e.g. inet6_dump_fib(),
fib6_tables_dump() and ipv6_route_seq_ops. It is because
fib6_walk_continue() makes modifications to the walker structure, and so
are fib6_repair_tree() and fib6_del_route(). In order to do proper
syncing between them, we need to let fib6_walk_continue() hold the lock.
We may be able to do further improvement on the way we do the tree walk
to get rid of the need for holding the spin lock. But not for now.
4. When fib6_del_route() removes a route from the tree, we no longer
mark rt->dst.rt6_next to NULL to make simultaneous reader be able to
further traverse the list with rcu. However, rt->dst.rt6_next is only
valid within this same rcu period. No one should access it later.
5. All the operation of atomic_inc(rt->rt6i_ref) is changed to be
performed before we publish this route (either by linking it to fn->leaf
or insert it in the list pointed by fn->leaf) just to be safe because as
soon as we publish the route, some read thread will be able to access it.
Signed-off-by: Wei Wang <weiwan@google.com>
Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
After rwlock is replaced with rcu and spinlock, fib6_lookup() could
potentially return an intermediate node if other thread is doing
fib6_del() on a route which is the only route on the node so that
fib6_repair_tree() will be called on this node and potentially assigns
fn->leaf to the its child's fn->leaf.
In order to detect this situation in rt6_select(), we have to check if
fn->fn_bit is consistent with the key length stored in the route. And
depending on if the fn is in the subtree or not, the key is either
rt->rt6i_dst or rt->rt6i_src.
If any inconsistency is found, that means the node no longer holds valid
routes in it. So net->ipv6.ip6_null_entry is returned.
Signed-off-by: Wei Wang <weiwan@google.com>
Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
If rwlock is replaced with rcu and spinlock, it is possible that the
reader thread will see fn->leaf as NULL in the following scenarios:
1. fib6_add() is in progress and we have already inserted a new node but
not yet inserted the route.
2. fib6_del_route() is in progress and we have already set fn->leaf to
NULL but not yet freed the node because of rcu grace period.
This patch makes sure all the reader threads check fn->leaf first before
using it. And together with later patch to grab rcu_read_lock() and
rcu_dereference() fn->leaf, it makes sure reader threads are safe when
accessing fn->leaf.
Signed-off-by: Wei Wang <weiwan@google.com>
Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
fib6_add() logic currently calls fib6_add_1() to figure out what node
should be used for the newly added route and then call
fib6_add_rt2node() to insert the route to the node.
And during the call of fib6_add_1(), fn_sernum is updated for all nodes
that share the same prefix as the new route.
This does not have issue in the current code because reader thread will
not be able to access the tree while writer thread is inserting new
route to it. However, it is not the case once we transition to use RCU.
Reader thread could potentially see the new fn_sernum before the new
route is inserted. As a result, reader thread's route lookup will return
a stale route with the new fn_sernum.
In order to solve this issue, we remove all the update of fn_sernum in
fib6_add_1(), and instead, introduce a new function that updates fn_sernum
for all related nodes and call this functions once the route is
successfully inserted to the tree.
Also, smp_wmb() is used after a route is successfully inserted into the
fib tree and right before the updated of fn->sernum. And smp_rmb() is
used right after fn->sernum is accessed in rt6_get_cookie_safe(). This
is to guarantee that when the reader thread sees the new fn->sernum, the
new route is already inserted in the tree in memory.
Signed-off-by: Wei Wang <weiwan@google.com>
Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
With rwlock, it is safe to call dst_hold() in the read thread because
read thread is guaranteed to be separated from write thread.
However, after we replace rwlock with rcu, it is no longer safe to use
dst_hold(). A dst might already have been deleted but is waiting for the
rcu grace period to pass before freeing the memory when a read thread is
trying to do dst_hold(). This could potentially cause double free issue.
So this commit replaces all dst_hold() with dst_hold_safe() in all read
thread to avoid this double free issue.
And in order to make the code more compact, a new function ip6_hold_safe()
is introduced. It calls dst_hold_safe() first, and if that fails, it will
either fall back to hold and return net->ipv6.ip6_null_entry or set rt to
NULL according to the caller's need.
Signed-off-by: Wei Wang <weiwan@google.com>
Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
After rwlock is replaced with rcu and spinlock, route lookup can happen
simultanously with route deletion.
This patch removes the call to free_percpu(rt->rt6i_pcpu) from
rt6_release() to avoid the race condition between rt6_release() and
rt6_get_pcpu_route(). And as free_percpu(rt->rt6i_pcpu) is already
called in ip6_dst_destroy() after the rcu grace period, it is safe to do
this change.
Signed-off-by: Wei Wang <weiwan@google.com>
Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
After rwlock is replaced with rcu and spinlock, ip6_pol_route() will be
called with only rcu held. That means rt6 route deletion could happen
simultaneously with rt6_make_pcpu_rt(). This could potentially cause
memory leak if rt6_release() is called right before rt6_make_pcpu_rt()
on the same route.
This patch grabs rt->rt6i_ref safely before calling rt6_make_pcpu_rt()
to make sure rt6_release() will not get triggered while
rt6_make_pcpu_rt() is in progress. And rt6_release() is called after
rt6_make_pcpu_rt() is finished.
Note: As we are incrementing rt->rt6i_ref in ip6_pol_route(), there is a
very slim chance that fib6_purge_rt() will be triggered unnecessarily
when deleting a route if ip6_pol_route() running on another thread picks
this route as well and tries to make pcpu cache for it.
Signed-off-by: Wei Wang <weiwan@google.com>
Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Shmulik Ladkani
Wei Wang
Eric Dumazet
Song Liu
David S. Miller
Paolo Abeni
David Ahern
Gustavo A. R. Silva
Kees Cook
Florian Westphal
Colin Ian King
Steffen Klassert
Lin Zhang
Alexey Kodanev
Matteo Croce