ipv4: Use inet_sk_init_flowi4() in ip4_datagram_release_cb().

Use inet_sk_init_flowi4() to automatically initialise the flowi4
structure in ip4_datagram_release_cb() instead of passing parameters
ma

ipv4: Use inet_sk_init_flowi4() in ip4_datagram_release_cb().

Use inet_sk_init_flowi4() to automatically initialise the flowi4
structure in ip4_datagram_release_cb() instead of passing parameters
manually to ip_route_output_ports().

Signed-off-by: Guillaume Nault <[email protected]>
Link: https://patch.msgid.link/9c326b8d9e919478f7952b21473d31da07eba2dd.1734357769.git.gnault@redhat.com
Signed-off-by: Jakub Kicinski <[email protected]>

show more ...

udp: fix l4 hash after reconnect

After the blamed commit below, udp_rehash() is supposed to be called
with both local and remote addresses set.

Currently that is already the case for IPv6 sockets,

udp: fix l4 hash after reconnect

After the blamed commit below, udp_rehash() is supposed to be called
with both local and remote addresses set.

Currently that is already the case for IPv6 sockets, but for IPv4 the
destination address is updated after rehashing.

Address the issue moving the destination address and port initialization
before rehashing.

Fixes: 1b29a730ef8b ("ipv6/udp: Add 4-tuple hash for connected socket")
Reviewed-by: Eric Dumazet <[email protected]>
Link: https://patch.msgid.link/4761e466ab9f7542c68cdc95f248987d127044d2.1733499715.git.pabeni@redhat.com
Signed-off-by: Paolo Abeni <[email protected]>

show more ...

ipv4: Set the routing scope properly in ip_route_output_ports().

Set scope automatically in ip_route_output_ports() (using the socket
SOCK_LOCALROUTE flag). This way, callers don't have to overload

ipv4: Set the routing scope properly in ip_route_output_ports().

Set scope automatically in ip_route_output_ports() (using the socket
SOCK_LOCALROUTE flag). This way, callers don't have to overload the
tos with the RTO_ONLINK flag, like RT_CONN_FLAGS() does.

For callers that don't pass a struct sock, this doesn't change anything
as the scope is still set to RT_SCOPE_UNIVERSE when sk is NULL.

Callers that passed a struct sock and used RT_CONN_FLAGS(sk) or
RT_CONN_FLAGS_TOS(sk, tos) for the tos are modified to use
ip_sock_tos(sk) and RT_TOS(tos) respectively, as overloading tos with
the RTO_ONLINK flag now becomes unnecessary.

In drivers/net/amt.c, all ip_route_output_ports() calls use a 0 tos
parameter, ignoring the SOCK_LOCALROUTE flag of the socket. But the sk
parameter is a kernel socket, which doesn't have any configuration path
for setting SOCK_LOCALROUTE anyway. Therefore, ip_route_output_ports()
will continue to initialise scope with RT_SCOPE_UNIVERSE and amt.c
doesn't need to be modified.

Also, remove RT_CONN_FLAGS() and RT_CONN_FLAGS_TOS() from route.h as
these macros are now unused.

The objective is to eventually remove RTO_ONLINK entirely to allow
converting ->flowi4_tos to dscp_t. This will ensure proper isolation
between the DSCP and ECN bits, thus minimising the risk of introducing
bugs where TOS values interfere with ECN.

Signed-off-by: Guillaume Nault <[email protected]>
Reviewed-by: David Ahern <[email protected]>
Link: https://lore.kernel.org/r/dacfd2ab40685e20959ab7b53c427595ba229e7d.1707496938.git.gnault@redhat.com
Signed-off-by: Jakub Kicinski <[email protected]>

show more ...

inet: implement lockless getsockopt(IP_MULTICAST_IF)

Add missing annotations to inet->mc_index and inet->mc_addr
to fix data-races.

getsockopt(IP_MULTICAST_IF) can be lockless.

setsockopt() side i

inet: implement lockless getsockopt(IP_MULTICAST_IF)

Add missing annotations to inet->mc_index and inet->mc_addr
to fix data-races.

getsockopt(IP_MULTICAST_IF) can be lockless.

setsockopt() side is left for later.

Signed-off-by: Eric Dumazet <[email protected]>
Reviewed-by: David Ahern <[email protected]>
Signed-off-by: David S. Miller <[email protected]>

show more ...

inet: implement lockless getsockopt(IP_UNICAST_IF)

Add missing READ_ONCE() annotations when reading inet->uc_index

Implementing getsockopt(IP_UNICAST_IF) locklessly seems possible,
the setsockopt()

inet: implement lockless getsockopt(IP_UNICAST_IF)

Add missing READ_ONCE() annotations when reading inet->uc_index

Implementing getsockopt(IP_UNICAST_IF) locklessly seems possible,
the setsockopt() part might not be possible at the moment.

Signed-off-by: Eric Dumazet <[email protected]>
Reviewed-by: David Ahern <[email protected]>
Signed-off-by: David S. Miller <[email protected]>

show more ...

ipv4: fix data-races around inet->inet_id

UDP sendmsg() is lockless, so ip_select_ident_segs()
can very well be run from multiple cpus [1]

Convert inet->inet_id to an atomic_t, but implement
a dedi

ipv4: fix data-races around inet->inet_id

UDP sendmsg() is lockless, so ip_select_ident_segs()
can very well be run from multiple cpus [1]

Convert inet->inet_id to an atomic_t, but implement
a dedicated path for TCP, avoiding cost of a locked
instruction (atomic_add_return())

Note that this patch will cause a trivial merge conflict
because we added inet->flags in net-next tree.

v2: added missing change in
drivers/net/ethernet/chelsio/inline_crypto/chtls/chtls_cm.c
(David Ahern)

[1]

BUG: KCSAN: data-race in __ip_make_skb / __ip_make_skb

read-write to 0xffff888145af952a of 2 bytes by task 7803 on cpu 1:
ip_select_ident_segs include/net/ip.h:542 [inline]
ip_select_ident include/net/ip.h:556 [inline]
__ip_make_skb+0x844/0xc70 net/ipv4/ip_output.c:1446
ip_make_skb+0x233/0x2c0 net/ipv4/ip_output.c:1560
udp_sendmsg+0x1199/0x1250 net/ipv4/udp.c:1260
inet_sendmsg+0x63/0x80 net/ipv4/af_inet.c:830
sock_sendmsg_nosec net/socket.c:725 [inline]
sock_sendmsg net/socket.c:748 [inline]
____sys_sendmsg+0x37c/0x4d0 net/socket.c:2494
___sys_sendmsg net/socket.c:2548 [inline]
__sys_sendmmsg+0x269/0x500 net/socket.c:2634
__do_sys_sendmmsg net/socket.c:2663 [inline]
__se_sys_sendmmsg net/socket.c:2660 [inline]
__x64_sys_sendmmsg+0x57/0x60 net/socket.c:2660
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x63/0xcd

read to 0xffff888145af952a of 2 bytes by task 7804 on cpu 0:
ip_select_ident_segs include/net/ip.h:541 [inline]
ip_select_ident include/net/ip.h:556 [inline]
__ip_make_skb+0x817/0xc70 net/ipv4/ip_output.c:1446
ip_make_skb+0x233/0x2c0 net/ipv4/ip_output.c:1560
udp_sendmsg+0x1199/0x1250 net/ipv4/udp.c:1260
inet_sendmsg+0x63/0x80 net/ipv4/af_inet.c:830
sock_sendmsg_nosec net/socket.c:725 [inline]
sock_sendmsg net/socket.c:748 [inline]
____sys_sendmsg+0x37c/0x4d0 net/socket.c:2494
___sys_sendmsg net/socket.c:2548 [inline]
__sys_sendmmsg+0x269/0x500 net/socket.c:2634
__do_sys_sendmmsg net/socket.c:2663 [inline]
__se_sys_sendmmsg net/socket.c:2660 [inline]
__x64_sys_sendmmsg+0x57/0x60 net/socket.c:2660
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x63/0xcd

value changed: 0x184d -> 0x184e

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 7804 Comm: syz-executor.1 Not tainted 6.5.0-rc6-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/26/2023
==================================================================

Fixes: 23f57406b82d ("ipv4: avoid using shared IP generator for connected sockets")
Reported-by: syzbot <[email protected]>
Signed-off-by: Eric Dumazet <[email protected]>
Reviewed-by: David Ahern <[email protected]>
Signed-off-by: David S. Miller <[email protected]>

show more ...

udp: Update reuse->has_conns under reuseport_lock.

When we call connect() for a UDP socket in a reuseport group, we have
to update sk->sk_reuseport_cb->has_conns to 1. Otherwise, the kernel
could s

udp: Update reuse->has_conns under reuseport_lock.

When we call connect() for a UDP socket in a reuseport group, we have
to update sk->sk_reuseport_cb->has_conns to 1. Otherwise, the kernel
could select a unconnected socket wrongly for packets sent to the
connected socket.

However, the current way to set has_conns is illegal and possible to
trigger that problem. reuseport_has_conns() changes has_conns under
rcu_read_lock(), which upgrades the RCU reader to the updater. Then,
it must do the update under the updater's lock, reuseport_lock, but
it doesn't for now.

For this reason, there is a race below where we fail to set has_conns
resulting in the wrong socket selection. To avoid the race, let's split
the reader and updater with proper locking.

cpu1 cpu2
+----+ +----+

__ip[46]_datagram_connect() reuseport_grow()
. .
|- reuseport_has_conns(sk, true) |- more_reuse = __reuseport_alloc(more_socks_size)
| . |
| |- rcu_read_lock()
| |- reuse = rcu_dereference(sk->sk_reuseport_cb)
| |
| | | /* reuse->has_conns == 0 here */
| | |- more_reuse->has_conns = reuse->has_conns
| |- reuse->has_conns = 1 | /* more_reuse->has_conns SHOULD BE 1 HERE */
| | |
| | |- rcu_assign_pointer(reuse->socks[i]->sk_reuseport_cb,
| | | more_reuse)
| `- rcu_read_unlock() `- kfree_rcu(reuse, rcu)
|
|- sk->sk_state = TCP_ESTABLISHED

Note the likely(reuse) in reuseport_has_conns_set() is always true,
but we put the test there for ease of review. [0]

For the record, usually, sk_reuseport_cb is changed under lock_sock().
The only exception is reuseport_grow() & TCP reqsk migration case.

1) shutdown() TCP listener, which is moved into the latter part of
reuse->socks[] to migrate reqsk.

2) New listen() overflows reuse->socks[] and call reuseport_grow().

3) reuse->max_socks overflows u16 with the new listener.

4) reuseport_grow() pops the old shutdown()ed listener from the array
and update its sk->sk_reuseport_cb as NULL without lock_sock().

shutdown()ed TCP sk->sk_reuseport_cb can be changed without lock_sock(),
but, reuseport_has_conns_set() is called only for UDP under lock_sock(),
so likely(reuse) never be false in reuseport_has_conns_set().

[0]: https://lore.kernel.org/netdev/CANn89iLja=eQHbsM_Ta2sQF0tOGU8vAGrh_izRuuHjuO1ouUag@mail.gmail.com/

Fixes: acdcecc61285 ("udp: correct reuseport selection with connected sockets")
Signed-off-by: Kuniyuki Iwashima <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Paolo Abeni <[email protected]>

show more ...

treewide: use get_random_{u8,u16}() when possible, part 1

Rather than truncate a 32-bit value to a 16-bit value or an 8-bit value,
simply use the get_random_{u8,u16}() functions, which are faster th

treewide: use get_random_{u8,u16}() when possible, part 1

Rather than truncate a 32-bit value to a 16-bit value or an 8-bit value,
simply use the get_random_{u8,u16}() functions, which are faster than
wasting the additional bytes from a 32-bit value. This was done
mechanically with this coccinelle script:

@@
expression E;
identifier get_random_u32 =~ "get_random_int|prandom_u32|get_random_u32";
typedef u16;
typedef __be16;
typedef __le16;
typedef u8;
@@
(
- (get_random_u32() & 0xffff)
+ get_random_u16()
|
- (get_random_u32() & 0xff)
+ get_random_u8()
|
- (get_random_u32() % 65536)
+ get_random_u16()
|
- (get_random_u32() % 256)
+ get_random_u8()
|
- (get_random_u32() >> 16)
+ get_random_u16()
|
- (get_random_u32() >> 24)
+ get_random_u8()
|
- (u16)get_random_u32()
+ get_random_u16()
|
- (u8)get_random_u32()
+ get_random_u8()
|
- (__be16)get_random_u32()
+ (__be16)get_random_u16()
|
- (__le16)get_random_u32()
+ (__le16)get_random_u16()
|
- prandom_u32_max(65536)
+ get_random_u16()
|
- prandom_u32_max(256)
+ get_random_u8()
|
- E->inet_id = get_random_u32()
+ E->inet_id = get_random_u16()
)

@@
identifier get_random_u32 =~ "get_random_int|prandom_u32|get_random_u32";
typedef u16;
identifier v;
@@
- u16 v = get_random_u32();
+ u16 v = get_random_u16();

@@
identifier get_random_u32 =~ "get_random_int|prandom_u32|get_random_u32";
typedef u8;
identifier v;
@@
- u8 v = get_random_u32();
+ u8 v = get_random_u8();

@@
identifier get_random_u32 =~ "get_random_int|prandom_u32|get_random_u32";
typedef u16;
u16 v;
@@
- v = get_random_u32();
+ v = get_random_u16();

@@
identifier get_random_u32 =~ "get_random_int|prandom_u32|get_random_u32";
typedef u8;
u8 v;
@@
- v = get_random_u32();
+ v = get_random_u8();

// Find a potential literal
@literal_mask@
expression LITERAL;
type T;
identifier get_random_u32 =~ "get_random_int|prandom_u32|get_random_u32";
position p;
@@

((T)get_random_u32()@p & (LITERAL))

// Examine limits
@script:python add_one@
literal << literal_mask.LITERAL;
RESULT;
@@

value = None
if literal.startswith('0x'):
value = int(literal, 16)
elif literal[0] in '123456789':
value = int(literal, 10)
if value is None:
print("I don't know how to handle %s" % (literal))
cocci.include_match(False)
elif value < 256:
coccinelle.RESULT = cocci.make_ident("get_random_u8")
elif value < 65536:
coccinelle.RESULT = cocci.make_ident("get_random_u16")
else:
print("Skipping large mask of %s" % (literal))
cocci.include_match(False)

// Replace the literal mask with the calculated result.
@plus_one@
expression literal_mask.LITERAL;
position literal_mask.p;
identifier add_one.RESULT;
identifier FUNC;
@@

- (FUNC()@p & (LITERAL))
+ (RESULT() & LITERAL)

Reviewed-by: Greg Kroah-Hartman <[email protected]>
Reviewed-by: Kees Cook <[email protected]>
Reviewed-by: Yury Norov <[email protected]>
Acked-by: Jakub Kicinski <[email protected]>
Acked-by: Toke Høiland-Jørgensen <[email protected]> # for sch_cake
Signed-off-by: Jason A. Donenfeld <[email protected]>

show more ...

net-next: Fix IP_UNICAST_IF option behavior for connected sockets

The IP_UNICAST_IF socket option is used to set the outgoing interface
for outbound packets.

The IP_UNICAST_IF socket option was add

net-next: Fix IP_UNICAST_IF option behavior for connected sockets

The IP_UNICAST_IF socket option is used to set the outgoing interface
for outbound packets.

The IP_UNICAST_IF socket option was added as it was needed by the
Wine project, since no other existing option (SO_BINDTODEVICE socket
option, IP_PKTINFO socket option or the bind function) provided the
needed characteristics needed by the IP_UNICAST_IF socket option. [1]
The IP_UNICAST_IF socket option works well for unconnected sockets,
that is, the interface specified by the IP_UNICAST_IF socket option
is taken into consideration in the route lookup process when a packet
is being sent. However, for connected sockets, the outbound interface
is chosen when connecting the socket, and in the route lookup process
which is done when a packet is being sent, the interface specified by
the IP_UNICAST_IF socket option is being ignored.

This inconsistent behavior was reported and discussed in an issue
opened on systemd's GitHub project [2]. Also, a bug report was
submitted in the kernel's bugzilla [3].

To understand the problem in more detail, we can look at what happens
for UDP packets over IPv4 (The same analysis was done separately in
the referenced systemd issue).
When a UDP packet is sent the udp_sendmsg function gets called and
the following happens:

1. The oif member of the struct ipcm_cookie ipc (which stores the
output interface of the packet) is initialized by the ipcm_init_sk
function to inet->sk.sk_bound_dev_if (the device set by the
SO_BINDTODEVICE socket option).

2. If the IP_PKTINFO socket option was set, the oif member gets
overridden by the call to the ip_cmsg_send function.

3. If no output interface was selected yet, the interface specified
by the IP_UNICAST_IF socket option is used.

4. If the socket is connected and no destination address is
specified in the send function, the struct ipcm_cookie ipc is not
taken into consideration and the cached route, that was calculated in
the connect function is being used.

Thus, for a connected socket, the IP_UNICAST_IF sockopt isn't taken
into consideration.

This patch corrects the behavior of the IP_UNICAST_IF socket option
for connect()ed sockets by taking into consideration the
IP_UNICAST_IF sockopt when connecting the socket.

In order to avoid reconnecting the socket, this option is still
ignored when applied on an already connected socket until connect()
is called again by the Richard Gobert.

Change the __ip4_datagram_connect function, which is called during
socket connection, to take into consideration the interface set by
the IP_UNICAST_IF socket option, in a similar way to what is done in
the udp_sendmsg function.

[1] https://lore.kernel.org/netdev/1328685717.4736.4.camel@edumazet-laptop/T/
[2] https://github.com/systemd/systemd/issues/11935#issuecomment-618691018
[3] https://bugzilla.kernel.org/show_bug.cgi?id=210255

Signed-off-by: Richard Gobert <[email protected]>
Reviewed-by: David Ahern <[email protected]>
Link: https://lore.kernel.org/r/20220829111554.GA1771@debian
Signed-off-by: Jakub Kicinski <[email protected]>

show more ...

ipv4: Avoid using RTO_ONLINK with ip_route_connect().

Now that ip_rt_fix_tos() doesn't reset ->flowi4_scope unconditionally,
we don't have to rely on the RTO_ONLINK bit to properly set the scope
of

ipv4: Avoid using RTO_ONLINK with ip_route_connect().

Now that ip_rt_fix_tos() doesn't reset ->flowi4_scope unconditionally,
we don't have to rely on the RTO_ONLINK bit to properly set the scope
of a flowi4 structure. We can just set ->flowi4_scope explicitly and
avoid using RTO_ONLINK in ->flowi4_tos.

This patch converts callers of ip_route_connect(). Instead of setting
the tos parameter with RT_CONN_FLAGS(sk), as all callers do, we can:

1- Drop the tos parameter from ip_route_connect(): its value was
entirely based on sk, which is also passed as parameter.

2- Set ->flowi4_scope depending on the SOCK_LOCALROUTE socket option
instead of always initialising it with RT_SCOPE_UNIVERSE (let's
define ip_sock_rt_scope() for this purpose).

3- Avoid overloading ->flowi4_tos with RTO_ONLINK: since the scope is
now properly initialised, we don't need to tell ip_rt_fix_tos() to
adjust ->flowi4_scope for us. So let's define ip_sock_rt_tos(),
which is the same as RT_CONN_FLAGS() but without the RTO_ONLINK
bit overload.

Note:
In the original ip_route_connect() code, __ip_route_output_key()
might clear the RTO_ONLINK bit of fl4->flowi4_tos (because of
ip_rt_fix_tos()). Therefore flowi4_update_output() had to reuse the
original tos variable. Now that we don't set RTO_ONLINK any more,
this is not a problem and we can use fl4->flowi4_tos in
flowi4_update_output().

Signed-off-by: Guillaume Nault <[email protected]>
Reviewed-by: David Ahern <[email protected]>
Signed-off-by: David S. Miller <[email protected]>

show more ...

net/ipv4/datagram.c: remove superfluous header files from datagram.c

datagram.c hasn't use any macro or function declared in linux/ip.h.
Thus, these files can be removed from datagram.c safely witho

net/ipv4/datagram.c: remove superfluous header files from datagram.c

datagram.c hasn't use any macro or function declared in linux/ip.h.
Thus, these files can be removed from datagram.c safely without
affecting the compilation of the net/ipv4 module

Signed-off-by: Mianhan Liu <[email protected]>
Signed-off-by: David S. Miller <[email protected]>

show more ...

inet: stop leaking jiffies on the wire

Historically linux tried to stick to RFC 791, 1122, 2003
for IPv4 ID field generation.

RFC 6864 made clear that no matter how hard we try,
we can not ensure u

inet: stop leaking jiffies on the wire

Historically linux tried to stick to RFC 791, 1122, 2003
for IPv4 ID field generation.

RFC 6864 made clear that no matter how hard we try,
we can not ensure unicity of IP ID within maximum
lifetime for all datagrams with a given source
address/destination address/protocol tuple.

Linux uses a per socket inet generator (inet_id), initialized
at connection startup with a XOR of 'jiffies' and other
fields that appear clear on the wire.

Thiemo Nagel pointed that this strategy is a privacy
concern as this provides 16 bits of entropy to fingerprint
devices.

Let's switch to a random starting point, this is just as
good as far as RFC 6864 is concerned and does not leak
anything critical.

Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Signed-off-by: Eric Dumazet <[email protected]>
Reported-by: Thiemo Nagel <[email protected]>
Signed-off-by: David S. Miller <[email protected]>

show more ...

udp: correct reuseport selection with connected sockets

UDP reuseport groups can hold a mix unconnected and connected sockets.
Ensure that connections only receive all traffic to their 4-tuple.

Fas

udp: correct reuseport selection with connected sockets

UDP reuseport groups can hold a mix unconnected and connected sockets.
Ensure that connections only receive all traffic to their 4-tuple.

Fast reuseport returns on the first reuseport match on the assumption
that all matches are equal. Only if connections are present, return to
the previous behavior of scoring all sockets.

Record if connections are present and if so (1) treat such connected
sockets as an independent match from the group, (2) only return
2-tuple matches from reuseport and (3) do not return on the first
2-tuple reuseport match to allow for a higher scoring match later.

New field has_conns is set without locks. No other fields in the
bitmap are modified at runtime and the field is only ever set
unconditionally, so an RMW cannot miss a change.

Fixes: e32ea7e74727 ("soreuseport: fast reuseport UDP socket selection")
Link: http://lkml.kernel.org/r/CA+FuTSfRP09aJNYRt04SS6qj22ViiOEWaWmLAwX0psk8-PGNxw@mail.gmail.com
Signed-off-by: Willem de Bruijn <[email protected]>
Acked-by: Paolo Abeni <[email protected]>
Acked-by: Craig Gallek <[email protected]>
Signed-off-by: Willem de Bruijn <[email protected]>
Signed-off-by: David S. Miller <[email protected]>

show more ...

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

Based on 1 normalized pattern(s):

this program is free software you can redistribute it and or modify
it under the terms of th

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

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 <[email protected]>
Reviewed-by: Allison Randal <[email protected]>
Cc: [email protected]
Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>

show more ...

ipv4: Allow sending multicast packets on specific i/f using VRF socket

It is useful to be able to use the same socket for listening in a
specific VRF, as for sending multicast packets out of a speci

ipv4: Allow sending multicast packets on specific i/f using VRF socket

It is useful to be able to use the same socket for listening in a
specific VRF, as for sending multicast packets out of a specific
interface. However, the bound device on the socket currently takes
precedence and results in the packets not being sent.

Relax the condition on overriding the output interface to use for
sending packets out of UDP, raw and ping sockets to allow multicast
packets to be sent using the specified multicast interface.

Signed-off-by: Robert Shearman <[email protected]>
Signed-off-by: Mike Manning <[email protected]>
Reviewed-by: David Ahern <[email protected]>
Signed-off-by: David S. Miller <[email protected]>

show more ...

net: Set sk_txhash from a random number

This patch creates sk_set_txhash and eliminates protocol specific
inet_set_txhash and ip6_set_txhash. sk_set_txhash simply sets a
random number instead of per

net: Set sk_txhash from a random number

This patch creates sk_set_txhash and eliminates protocol specific
inet_set_txhash and ip6_set_txhash. sk_set_txhash simply sets a
random number instead of performing flow dissection. sk_set_txash
is also allowed to be called multiple times for the same socket,
we'll need this when redoing the hash for negative routing advice.

Signed-off-by: Tom Herbert <[email protected]>
Signed-off-by: David S. Miller <[email protected]>

show more ...

ipv6: lock socket in ip6_datagram_connect()

ip6_datagram_connect() is doing a lot of socket changes without
socket being locked.

This looks wrong, at least for udp_lib_rehash() which could corrupt

ipv6: lock socket in ip6_datagram_connect()

ip6_datagram_connect() is doing a lot of socket changes without
socket being locked.

This looks wrong, at least for udp_lib_rehash() which could corrupt
lists because of concurrent udp_sk(sk)->udp_portaddr_hash accesses.

Signed-off-by: Eric Dumazet <[email protected]>
Acked-by: Herbert Xu <[email protected]>
Signed-off-by: David S. Miller <[email protected]>

show more ...

net: Save TX flow hash in sock and set in skbuf on xmit

For a connected socket we can precompute the flow hash for setting
in skb->hash on output. This is a performance advantage over
calculating th

net: Save TX flow hash in sock and set in skbuf on xmit

For a connected socket we can precompute the flow hash for setting
in skb->hash on output. This is a performance advantage over
calculating the skb->hash for every packet on the connection. The
computation is done using the common hash algorithm to be consistent
with computations done for packets of the connection in other states
where thers is no socket (e.g. time-wait, syn-recv, syn-cookies).

This patch adds sk_txhash to the sock structure. inet_set_txhash and
ip6_set_txhash functions are added which are called from points in
TCP and UDP where socket moves to established state.

skb_set_hash_from_sk is a function which sets skb->hash from the
sock txhash value. This is called in UDP and TCP transmit path when
transmitting within the context of a socket.

Tested: ran super_netperf with 200 TCP_RR streams over a vxlan
interface (in this case skb_get_hash called on every TX packet to
create a UDP source port).

Before fix:

95.02% CPU utilization
154/256/505 90/95/99% latencies
1.13042e+06 tps

Time in functions:
0.28% skb_flow_dissect
0.21% __skb_get_hash

After fix:

94.95% CPU utilization
156/254/485 90/95/99% latencies
1.15447e+06

Neither __skb_get_hash nor skb_flow_dissect appear in perf

Signed-off-by: Tom Herbert <[email protected]>
Signed-off-by: David S. Miller <[email protected]>

show more ...

ipv4: fix a race in ip4_datagram_release_cb()

Alexey gave a AddressSanitizer[1] report that finally gave a good hint
at where was the origin of various problems already reported by Dormando
in the p

ipv4: fix a race in ip4_datagram_release_cb()

Alexey gave a AddressSanitizer[1] report that finally gave a good hint
at where was the origin of various problems already reported by Dormando
in the past [2]

Problem comes from the fact that UDP can have a lockless TX path, and
concurrent threads can manipulate sk_dst_cache, while another thread,
is holding socket lock and calls __sk_dst_set() in
ip4_datagram_release_cb() (this was added in linux-3.8)

It seems that all we need to do is to use sk_dst_check() and
sk_dst_set() so that all the writers hold same spinlock
(sk->sk_dst_lock) to prevent corruptions.

TCP stack do not need this protection, as all sk_dst_cache writers hold
the socket lock.

[1]
https://code.google.com/p/address-sanitizer/wiki/AddressSanitizerForKernel

AddressSanitizer: heap-use-after-free in ipv4_dst_check
Read of size 2 by thread T15453:
[<ffffffff817daa3a>] ipv4_dst_check+0x1a/0x90 ./net/ipv4/route.c:1116
[<ffffffff8175b789>] __sk_dst_check+0x89/0xe0 ./net/core/sock.c:531
[<ffffffff81830a36>] ip4_datagram_release_cb+0x46/0x390 ??:0
[<ffffffff8175eaea>] release_sock+0x17a/0x230 ./net/core/sock.c:2413
[<ffffffff81830882>] ip4_datagram_connect+0x462/0x5d0 ??:0
[<ffffffff81846d06>] inet_dgram_connect+0x76/0xd0 ./net/ipv4/af_inet.c:534
[<ffffffff817580ac>] SYSC_connect+0x15c/0x1c0 ./net/socket.c:1701
[<ffffffff817596ce>] SyS_connect+0xe/0x10 ./net/socket.c:1682
[<ffffffff818b0a29>] system_call_fastpath+0x16/0x1b
./arch/x86/kernel/entry_64.S:629

Freed by thread T15455:
[<ffffffff8178d9b8>] dst_destroy+0xa8/0x160 ./net/core/dst.c:251
[<ffffffff8178de25>] dst_release+0x45/0x80 ./net/core/dst.c:280
[<ffffffff818304c1>] ip4_datagram_connect+0xa1/0x5d0 ??:0
[<ffffffff81846d06>] inet_dgram_connect+0x76/0xd0 ./net/ipv4/af_inet.c:534
[<ffffffff817580ac>] SYSC_connect+0x15c/0x1c0 ./net/socket.c:1701
[<ffffffff817596ce>] SyS_connect+0xe/0x10 ./net/socket.c:1682
[<ffffffff818b0a29>] system_call_fastpath+0x16/0x1b
./arch/x86/kernel/entry_64.S:629

Allocated by thread T15453:
[<ffffffff8178d291>] dst_alloc+0x81/0x2b0 ./net/core/dst.c:171
[<ffffffff817db3b7>] rt_dst_alloc+0x47/0x50 ./net/ipv4/route.c:1406
[< inlined >] __ip_route_output_key+0x3e8/0xf70
__mkroute_output ./net/ipv4/route.c:1939
[<ffffffff817dde08>] __ip_route_output_key+0x3e8/0xf70 ./net/ipv4/route.c:2161
[<ffffffff817deb34>] ip_route_output_flow+0x14/0x30 ./net/ipv4/route.c:2249
[<ffffffff81830737>] ip4_datagram_connect+0x317/0x5d0 ??:0
[<ffffffff81846d06>] inet_dgram_connect+0x76/0xd0 ./net/ipv4/af_inet.c:534
[<ffffffff817580ac>] SYSC_connect+0x15c/0x1c0 ./net/socket.c:1701
[<ffffffff817596ce>] SyS_connect+0xe/0x10 ./net/socket.c:1682
[<ffffffff818b0a29>] system_call_fastpath+0x16/0x1b
./arch/x86/kernel/entry_64.S:629

[2]
<4>[196727.311203] general protection fault: 0000 [#1] SMP
<4>[196727.311224] Modules linked in: xt_TEE xt_dscp xt_DSCP macvlan bridge coretemp crc32_pclmul ghash_clmulni_intel gpio_ich microcode ipmi_watchdog ipmi_devintf sb_edac edac_core lpc_ich mfd_core tpm_tis tpm tpm_bios ipmi_si ipmi_msghandler isci igb libsas i2c_algo_bit ixgbe ptp pps_core mdio
<4>[196727.311333] CPU: 17 PID: 0 Comm: swapper/17 Not tainted 3.10.26 #1
<4>[196727.311344] Hardware name: Supermicro X9DRi-LN4+/X9DR3-LN4+/X9DRi-LN4+/X9DR3-LN4+, BIOS 3.0 07/05/2013
<4>[196727.311364] task: ffff885e6f069700 ti: ffff885e6f072000 task.ti: ffff885e6f072000
<4>[196727.311377] RIP: 0010:[<ffffffff815f8c7f>] [<ffffffff815f8c7f>] ipv4_dst_destroy+0x4f/0x80
<4>[196727.311399] RSP: 0018:ffff885effd23a70 EFLAGS: 00010282
<4>[196727.311409] RAX: dead000000200200 RBX: ffff8854c398ecc0 RCX: 0000000000000040
<4>[196727.311423] RDX: dead000000100100 RSI: dead000000100100 RDI: dead000000200200
<4>[196727.311437] RBP: ffff885effd23a80 R08: ffffffff815fd9e0 R09: ffff885d5a590800
<4>[196727.311451] R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
<4>[196727.311464] R13: ffffffff81c8c280 R14: 0000000000000000 R15: ffff880e85ee16ce
<4>[196727.311510] FS: 0000000000000000(0000) GS:ffff885effd20000(0000) knlGS:0000000000000000
<4>[196727.311554] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
<4>[196727.311581] CR2: 00007a46751eb000 CR3: 0000005e65688000 CR4: 00000000000407e0
<4>[196727.311625] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
<4>[196727.311669] DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
<4>[196727.311713] Stack:
<4>[196727.311733] ffff8854c398ecc0 ffff8854c398ecc0 ffff885effd23ab0 ffffffff815b7f42
<4>[196727.311784] ffff88be6595bc00 ffff8854c398ecc0 0000000000000000 ffff8854c398ecc0
<4>[196727.311834] ffff885effd23ad0 ffffffff815b86c6 ffff885d5a590800 ffff8816827821c0
<4>[196727.311885] Call Trace:
<4>[196727.311907] <IRQ>
<4>[196727.311912] [<ffffffff815b7f42>] dst_destroy+0x32/0xe0
<4>[196727.311959] [<ffffffff815b86c6>] dst_release+0x56/0x80
<4>[196727.311986] [<ffffffff81620bd5>] tcp_v4_do_rcv+0x2a5/0x4a0
<4>[196727.312013] [<ffffffff81622b5a>] tcp_v4_rcv+0x7da/0x820
<4>[196727.312041] [<ffffffff815fd9e0>] ? ip_rcv_finish+0x360/0x360
<4>[196727.312070] [<ffffffff815de02d>] ? nf_hook_slow+0x7d/0x150
<4>[196727.312097] [<ffffffff815fd9e0>] ? ip_rcv_finish+0x360/0x360
<4>[196727.312125] [<ffffffff815fda92>] ip_local_deliver_finish+0xb2/0x230
<4>[196727.312154] [<ffffffff815fdd9a>] ip_local_deliver+0x4a/0x90
<4>[196727.312183] [<ffffffff815fd799>] ip_rcv_finish+0x119/0x360
<4>[196727.312212] [<ffffffff815fe00b>] ip_rcv+0x22b/0x340
<4>[196727.312242] [<ffffffffa0339680>] ? macvlan_broadcast+0x160/0x160 [macvlan]
<4>[196727.312275] [<ffffffff815b0c62>] __netif_receive_skb_core+0x512/0x640
<4>[196727.312308] [<ffffffff811427fb>] ? kmem_cache_alloc+0x13b/0x150
<4>[196727.312338] [<ffffffff815b0db1>] __netif_receive_skb+0x21/0x70
<4>[196727.312368] [<ffffffff815b0fa1>] netif_receive_skb+0x31/0xa0
<4>[196727.312397] [<ffffffff815b1ae8>] napi_gro_receive+0xe8/0x140
<4>[196727.312433] [<ffffffffa00274f1>] ixgbe_poll+0x551/0x11f0 [ixgbe]
<4>[196727.312463] [<ffffffff815fe00b>] ? ip_rcv+0x22b/0x340
<4>[196727.312491] [<ffffffff815b1691>] net_rx_action+0x111/0x210
<4>[196727.312521] [<ffffffff815b0db1>] ? __netif_receive_skb+0x21/0x70
<4>[196727.312552] [<ffffffff810519d0>] __do_softirq+0xd0/0x270
<4>[196727.312583] [<ffffffff816cef3c>] call_softirq+0x1c/0x30
<4>[196727.312613] [<ffffffff81004205>] do_softirq+0x55/0x90
<4>[196727.312640] [<ffffffff81051c85>] irq_exit+0x55/0x60
<4>[196727.312668] [<ffffffff816cf5c3>] do_IRQ+0x63/0xe0
<4>[196727.312696] [<ffffffff816c5aaa>] common_interrupt+0x6a/0x6a
<4>[196727.312722] <EOI>
<1>[196727.313071] RIP [<ffffffff815f8c7f>] ipv4_dst_destroy+0x4f/0x80
<4>[196727.313100] RSP <ffff885effd23a70>
<4>[196727.313377] ---[ end trace 64b3f14fae0f2e29 ]---
<0>[196727.380908] Kernel panic - not syncing: Fatal exception in interrupt

Reported-by: Alexey Preobrazhensky <[email protected]>
Reported-by: dormando <[email protected]>
Signed-off-by: Eric Dumazet <[email protected]>
Fixes: 8141ed9fcedb2 ("ipv4: Add a socket release callback for datagram sockets")
Cc: Steffen Klassert <[email protected]>
Signed-off-by: David S. Miller <[email protected]>

show more ...

net: Remove FLOWI_FLAG_CAN_SLEEP

FLOWI_FLAG_CAN_SLEEP was used to notify xfrm about the posibility
to sleep until the needed states are resolved. This code is gone,
so FLOWI_FLAG_CAN_SLEEP is not ne

net: Remove FLOWI_FLAG_CAN_SLEEP

FLOWI_FLAG_CAN_SLEEP was used to notify xfrm about the posibility
to sleep until the needed states are resolved. This code is gone,
so FLOWI_FLAG_CAN_SLEEP is not needed anymore.

Signed-off-by: Steffen Klassert <[email protected]>

show more ...

ipv4: fix possible seqlock deadlock

ip4_datagram_connect() being called from process context,
it should use IP_INC_STATS() instead of IP_INC_STATS_BH()
otherwise we can deadlock on 32bit arches, or

ipv4: fix possible seqlock deadlock

ip4_datagram_connect() being called from process context,
it should use IP_INC_STATS() instead of IP_INC_STATS_BH()
otherwise we can deadlock on 32bit arches, or get corruptions of
SNMP counters.

Fixes: 584bdf8cbdf6 ("[IPV4]: Fix "ipOutNoRoutes" counter error for TCP and UDP")
Signed-off-by: Eric Dumazet <[email protected]>
Reported-by: Dave Jones <[email protected]>
Signed-off-by: David S. Miller <[email protected]>

show more ...

ipv4: Add a socket release callback for datagram sockets

This implements a socket release callback function to check
if the socket cached route got invalid during the time
we owned the socket. The f

ipv4: Add a socket release callback for datagram sockets

This implements a socket release callback function to check
if the socket cached route got invalid during the time
we owned the socket. The function is used from udp, raw
and ping sockets.

Signed-off-by: Steffen Klassert <[email protected]>
Signed-off-by: David S. Miller <[email protected]>

show more ...

ipv4: Lock socket and use cork flow in ip4_datagram_connect().

This is to make sure that an l2tp socket's inet cork flow is
fully filled in, when it's encapsulated in UDP.

Signed-off-by: David S. M

ipv4: Lock socket and use cork flow in ip4_datagram_connect().

This is to make sure that an l2tp socket's inet cork flow is
fully filled in, when it's encapsulated in UDP.

Signed-off-by: David S. Miller <[email protected]>

show more ...

ipv4: Get route daddr from flow key in ip4_datagram_connect().

Now that output route lookups update the flow with
destination address selection, we can fetch it from
fl4->daddr instead of rt->rt_dst

ipv4: Get route daddr from flow key in ip4_datagram_connect().

Now that output route lookups update the flow with
destination address selection, we can fetch it from
fl4->daddr instead of rt->rt_dst

Signed-off-by: David S. Miller <[email protected]>

show more ...

ipv4: Fetch route saddr from flow key in ip4_datagram_connect().

Now that output route lookups update the flow with
source address selection, we can fetch it from
fl4->saddr instead of rt->rt_src

S

ipv4: Fetch route saddr from flow key in ip4_datagram_connect().

Now that output route lookups update the flow with
source address selection, we can fetch it from
fl4->saddr instead of rt->rt_src

Signed-off-by: David S. Miller <[email protected]>

show more ...