linux-stable.git/net/ipv4/ip_output.c, branch linux-6.7.y Linux kernel stable tree net: ipv4: fix a memleak in ip_setup_cork 2024-02-05T20:17:09+00:00 Zhipeng Lu alexious@zju.edu.cn 2024-01-29T09:10:17+00:00 205659dbb880b23a680e87dd1c814b97fc72be3d [ Upstream commit 5dee6d6923458e26966717f2a3eae7d09fc10bf6 ] When inetdev_valid_mtu fails, cork->opt should be freed if it is allocated in ip_setup_cork. Otherwise there could be a memleak. Fixes: 501a90c94510 ("inet: protect against too small mtu values.") Signed-off-by: Zhipeng Lu <alexious@zju.edu.cn> Reviewed-by: Eric Dumazet <edumazet@google.com> Link: https://lore.kernel.org/r/20240129091017.2938835-1-alexious@zju.edu.cn Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit 5dee6d6923458e26966717f2a3eae7d09fc10bf6 ]

When inetdev_valid_mtu fails, cork->opt should be freed if it is
allocated in ip_setup_cork. Otherwise there could be a memleak.

Fixes: 501a90c94510 ("inet: protect against too small mtu values.")
Signed-off-by: Zhipeng Lu <alexious@zju.edu.cn>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://lore.kernel.org/r/20240129091017.2938835-1-alexious@zju.edu.cn
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
net: fix IPSTATS_MIB_OUTPKGS increment in OutForwDatagrams. 2023-10-20T11:01:00+00:00 Heng Guo heng.guo@windriver.com 2023-10-19T01:20:53+00:00 b4a11b2033b7d3dfdd46592f7036a775b18cecd1 Reproduce environment: network with 3 VM linuxs is connected as below: VM1<---->VM2(latest kernel 6.5.0-rc7)<---->VM3 VM1: eth0 ip: 192.168.122.207 MTU 1500 VM2: eth0 ip: 192.168.122.208, eth1 ip: 192.168.123.224 MTU 1500 VM3: eth0 ip: 192.168.123.240 MTU 1500 Reproduce: VM1 send 1400 bytes UDP data to VM3 using tools scapy with flags=0. scapy command: send(IP(dst="192.168.123.240",flags=0)/UDP()/str('0'*1400),count=1, inter=1.000000) Result: Before IP data is sent. ---------------------------------------------------------------------- root@qemux86-64:~# cat /proc/net/snmp Ip: Forwarding DefaultTTL InReceives InHdrErrors InAddrErrors ForwDatagrams InUnknownProtos InDiscards InDelivers OutRequests OutDiscards OutNoRoutes ReasmTimeout ReasmReqds ReasmOKs ReasmFails FragOKs FragFails FragCreates Ip: 1 64 11 0 3 4 0 0 4 7 0 0 0 0 0 0 0 0 0 ...... ---------------------------------------------------------------------- After IP data is sent. ---------------------------------------------------------------------- root@qemux86-64:~# cat /proc/net/snmp Ip: Forwarding DefaultTTL InReceives InHdrErrors InAddrErrors ForwDatagrams InUnknownProtos InDiscards InDelivers OutRequests OutDiscards OutNoRoutes ReasmTimeout ReasmReqds ReasmOKs ReasmFails FragOKs FragFails FragCreates Ip: 1 64 12 0 3 5 0 0 4 8 0 0 0 0 0 0 0 0 0 ...... ---------------------------------------------------------------------- "ForwDatagrams" increase from 4 to 5 and "OutRequests" also increase from 7 to 8. Issue description and patch: IPSTATS_MIB_OUTPKTS("OutRequests") is counted with IPSTATS_MIB_OUTOCTETS ("OutOctets") in ip_finish_output2(). According to RFC 4293, it is "OutOctets" counted with "OutTransmits" but not "OutRequests". "OutRequests" does not include any datagrams counted in "ForwDatagrams". ipSystemStatsOutOctets OBJECT-TYPE DESCRIPTION "The total number of octets in IP datagrams delivered to the lower layers for transmission. Octets from datagrams counted in ipIfStatsOutTransmits MUST be counted here. ipSystemStatsOutRequests OBJECT-TYPE DESCRIPTION "The total number of IP datagrams that local IP user- protocols (including ICMP) supplied to IP in requests for transmission. Note that this counter does not include any datagrams counted in ipSystemStatsOutForwDatagrams. So do patch to define IPSTATS_MIB_OUTPKTS to "OutTransmits" and add IPSTATS_MIB_OUTREQUESTS for "OutRequests". Add IPSTATS_MIB_OUTREQUESTS counter in __ip_local_out() for ipv4 and add IPSTATS_MIB_OUT counter in ip6_finish_output2() for ipv6. Test result with patch: Before IP data is sent. ---------------------------------------------------------------------- root@qemux86-64:~# cat /proc/net/snmp Ip: Forwarding DefaultTTL InReceives InHdrErrors InAddrErrors ForwDatagrams InUnknownProtos InDiscards InDelivers OutRequests OutDiscards OutNoRoutes ReasmTimeout ReasmReqds ReasmOKs ReasmFails FragOKs FragFails FragCreates OutTransmits Ip: 1 64 9 0 5 1 0 0 3 3 0 0 0 0 0 0 0 0 0 4 ...... root@qemux86-64:~# cat /proc/net/netstat ...... IpExt: InNoRoutes InTruncatedPkts InMcastPkts OutMcastPkts InBcastPkts OutBcastPkts InOctets OutOctets InMcastOctets OutMcastOctets InBcastOctets OutBcastOctets InCsumErrors InNoECTPkts InECT1Pkts InECT0Pkts InCEPkts ReasmOverlaps IpExt: 0 0 0 0 0 0 2976 1896 0 0 0 0 0 9 0 0 0 0 ---------------------------------------------------------------------- After IP data is sent. ---------------------------------------------------------------------- root@qemux86-64:~# cat /proc/net/snmp Ip: Forwarding DefaultTTL InReceives InHdrErrors InAddrErrors ForwDatagrams InUnknownProtos InDiscards InDelivers OutRequests OutDiscards OutNoRoutes ReasmTimeout ReasmReqds ReasmOKs ReasmFails FragOKs FragFails FragCreates OutTransmits Ip: 1 64 10 0 5 2 0 0 3 3 0 0 0 0 0 0 0 0 0 5 ...... root@qemux86-64:~# cat /proc/net/netstat ...... IpExt: InNoRoutes InTruncatedPkts InMcastPkts OutMcastPkts InBcastPkts OutBcastPkts InOctets OutOctets InMcastOctets OutMcastOctets InBcastOctets OutBcastOctets InCsumErrors InNoECTPkts InECT1Pkts InECT0Pkts InCEPkts ReasmOverlaps IpExt: 0 0 0 0 0 0 4404 3324 0 0 0 0 0 10 0 0 0 0 ---------------------------------------------------------------------- "ForwDatagrams" increase from 1 to 2 and "OutRequests" is keeping 3. "OutTransmits" increase from 4 to 5 and "OutOctets" increase 1428. Signed-off-by: Heng Guo <heng.guo@windriver.com> Reviewed-by: Kun Song <Kun.Song@windriver.com> Reviewed-by: Filip Pudak <filip.pudak@windriver.com> Reviewed-by: David Ahern <dsahern@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net> 
Reproduce environment:
network with 3 VM linuxs is connected as below:
VM1<---->VM2(latest kernel 6.5.0-rc7)<---->VM3
VM1: eth0 ip: 192.168.122.207 MTU 1500
VM2: eth0 ip: 192.168.122.208, eth1 ip: 192.168.123.224 MTU 1500
VM3: eth0 ip: 192.168.123.240 MTU 1500

Reproduce:
VM1 send 1400 bytes UDP data to VM3 using tools scapy with flags=0.
scapy command:
send(IP(dst="192.168.123.240",flags=0)/UDP()/str('0'*1400),count=1,
inter=1.000000)

Result:
Before IP data is sent.
----------------------------------------------------------------------
root@qemux86-64:~# cat /proc/net/snmp
Ip: Forwarding DefaultTTL InReceives InHdrErrors InAddrErrors
  ForwDatagrams InUnknownProtos InDiscards InDelivers OutRequests
  OutDiscards OutNoRoutes ReasmTimeout ReasmReqds ReasmOKs ReasmFails
  FragOKs FragFails FragCreates
Ip: 1 64 11 0 3 4 0 0 4 7 0 0 0 0 0 0 0 0 0
......
----------------------------------------------------------------------
After IP data is sent.
----------------------------------------------------------------------
root@qemux86-64:~# cat /proc/net/snmp
Ip: Forwarding DefaultTTL InReceives InHdrErrors InAddrErrors
  ForwDatagrams InUnknownProtos InDiscards InDelivers OutRequests
  OutDiscards OutNoRoutes ReasmTimeout ReasmReqds ReasmOKs ReasmFails
  FragOKs FragFails FragCreates
Ip: 1 64 12 0 3 5 0 0 4 8 0 0 0 0 0 0 0 0 0
......
----------------------------------------------------------------------
"ForwDatagrams" increase from 4 to 5 and "OutRequests" also increase
from 7 to 8.

Issue description and patch:
IPSTATS_MIB_OUTPKTS("OutRequests") is counted with IPSTATS_MIB_OUTOCTETS
("OutOctets") in ip_finish_output2().
According to RFC 4293, it is "OutOctets" counted with "OutTransmits" but
not "OutRequests". "OutRequests" does not include any datagrams counted
in "ForwDatagrams".
ipSystemStatsOutOctets OBJECT-TYPE
    DESCRIPTION
           "The total number of octets in IP datagrams delivered to the
            lower layers for transmission.  Octets from datagrams
            counted in ipIfStatsOutTransmits MUST be counted here.
ipSystemStatsOutRequests OBJECT-TYPE
    DESCRIPTION
           "The total number of IP datagrams that local IP user-
            protocols (including ICMP) supplied to IP in requests for
            transmission.  Note that this counter does not include any
            datagrams counted in ipSystemStatsOutForwDatagrams.
So do patch to define IPSTATS_MIB_OUTPKTS to "OutTransmits" and add
IPSTATS_MIB_OUTREQUESTS for "OutRequests".
Add IPSTATS_MIB_OUTREQUESTS counter in __ip_local_out() for ipv4 and add
IPSTATS_MIB_OUT counter in ip6_finish_output2() for ipv6.

Test result with patch:
Before IP data is sent.
----------------------------------------------------------------------
root@qemux86-64:~# cat /proc/net/snmp
Ip: Forwarding DefaultTTL InReceives InHdrErrors InAddrErrors
  ForwDatagrams InUnknownProtos InDiscards InDelivers OutRequests
  OutDiscards OutNoRoutes ReasmTimeout ReasmReqds ReasmOKs ReasmFails
  FragOKs FragFails FragCreates OutTransmits
Ip: 1 64 9 0 5 1 0 0 3 3 0 0 0 0 0 0 0 0 0 4
......
root@qemux86-64:~# cat /proc/net/netstat
......
IpExt: InNoRoutes InTruncatedPkts InMcastPkts OutMcastPkts InBcastPkts
  OutBcastPkts InOctets OutOctets InMcastOctets OutMcastOctets
  InBcastOctets OutBcastOctets InCsumErrors InNoECTPkts InECT1Pkts
  InECT0Pkts InCEPkts ReasmOverlaps
IpExt: 0 0 0 0 0 0 2976 1896 0 0 0 0 0 9 0 0 0 0
----------------------------------------------------------------------
After IP data is sent.
----------------------------------------------------------------------
root@qemux86-64:~# cat /proc/net/snmp
Ip: Forwarding DefaultTTL InReceives InHdrErrors InAddrErrors
  ForwDatagrams InUnknownProtos InDiscards InDelivers OutRequests
  OutDiscards OutNoRoutes ReasmTimeout ReasmReqds ReasmOKs ReasmFails
  FragOKs FragFails FragCreates OutTransmits
Ip: 1 64 10 0 5 2 0 0 3 3 0 0 0 0 0 0 0 0 0 5
......
root@qemux86-64:~# cat /proc/net/netstat
......
IpExt: InNoRoutes InTruncatedPkts InMcastPkts OutMcastPkts InBcastPkts
  OutBcastPkts InOctets OutOctets InMcastOctets OutMcastOctets
  InBcastOctets OutBcastOctets InCsumErrors InNoECTPkts InECT1Pkts
  InECT0Pkts InCEPkts ReasmOverlaps
IpExt: 0 0 0 0 0 0 4404 3324 0 0 0 0 0 10 0 0 0 0
----------------------------------------------------------------------
"ForwDatagrams" increase from 1 to 2 and "OutRequests" is keeping 3.
"OutTransmits" increase from 4 to 5 and "OutOctets" increase 1428.

Signed-off-by: Heng Guo <heng.guo@windriver.com>
Reviewed-by: Kun Song <Kun.Song@windriver.com>
Reviewed-by: Filip Pudak <filip.pudak@windriver.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
inet: implement lockless IP_TOS 2023-10-01T18:39:18+00:00 Eric Dumazet edumazet@google.com 2023-09-22T03:42:16+00:00 e08d0b3d172311e2bb500865c0d0038533d0ff11 Some reads of inet->tos are racy. Add needed READ_ONCE() annotations and convert IP_TOS option lockless. v2: missing changes in include/net/route.h (David Ahern) Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: David Ahern <dsahern@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net> 
Some reads of inet->tos are racy.

Add needed READ_ONCE() annotations and convert IP_TOS option lockless.

v2: missing changes in include/net/route.h (David Ahern)

Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
inet: implement lockless IP_MTU_DISCOVER 2023-10-01T18:39:18+00:00 Eric Dumazet edumazet@google.com 2023-09-22T03:42:15+00:00 ceaa714138a372ac63cc2c5c19ee0882d22827f9 inet->pmtudisc can be read locklessly. Implement proper lockless reads and writes to inet->pmtudisc ip_sock_set_mtu_discover() can now be called from arbitrary contexts. Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: David Ahern <dsahern@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net> 
inet->pmtudisc can be read locklessly.

Implement proper lockless reads and writes to inet->pmtudisc

ip_sock_set_mtu_discover() can now be called from arbitrary
contexts.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
inet: implement lockless IP_MULTICAST_TTL 2023-10-01T18:39:18+00:00 Eric Dumazet edumazet@google.com 2023-09-22T03:42:14+00:00 c9746e6a19c24b2d9a74d6657daee3b39fdc1bec inet->mc_ttl can be read locklessly. Implement proper lockless reads and writes to inet->mc_ttl Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: David Ahern <dsahern@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net> 
inet->mc_ttl can be read locklessly.

Implement proper lockless reads and writes to inet->mc_ttl

Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
net: implement lockless SO_PRIORITY 2023-10-01T18:09:54+00:00 Eric Dumazet edumazet@google.com 2023-09-21T20:28:11+00:00 10bbf1652c1cca9819e98d56f3432c56d7a2d229 This is a followup of 8bf43be799d4 ("net: annotate data-races around sk->sk_priority"). sk->sk_priority can be read and written without holding the socket lock. Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Wenjia Zhang <wenjia@linux.ibm.com> Signed-off-by: David S. Miller <davem@davemloft.net> 
This is a followup of 8bf43be799d4 ("net: annotate data-races
around sk->sk_priority").

sk->sk_priority can be read and written without holding the socket lock.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Wenjia Zhang <wenjia@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
net: annotate data-races around sk->sk_tsflags 2023-09-01T06:27:33+00:00 Eric Dumazet edumazet@google.com 2023-08-31T13:52:11+00:00 e3390b30a5dfb112e8e802a59c0f68f947b638b2 sk->sk_tsflags can be read locklessly, add corresponding annotations. Fixes: b9f40e21ef42 ("net-timestamp: move timestamp flags out of sk_flags") Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Willem de Bruijn <willemb@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> 
sk->sk_tsflags can be read locklessly, add corresponding annotations.

Fixes: b9f40e21ef42 ("net-timestamp: move timestamp flags out of sk_flags")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
net: ipv4, ipv6: fix IPSTATS_MIB_OUTOCTETS increment duplicated 2023-08-30T08:44:09+00:00 Heng Guo heng.guo@windriver.com 2023-08-25T07:55:05+00:00 e4da8c78973c1e307c0431e0b99a969ffb8aa3f1 commit edf391ff1723 ("snmp: add missing counters for RFC 4293") had already added OutOctets for RFC 4293. In commit 2d8dbb04c63e ("snmp: fix OutOctets counter to include forwarded datagrams"), OutOctets was counted again, but not removed from ip_output(). According to RFC 4293 "3.2.3. IP Statistics Tables", ipipIfStatsOutTransmits is not equal to ipIfStatsOutForwDatagrams. So "IPSTATS_MIB_OUTOCTETS must be incremented when incrementing" is not accurate. And IPSTATS_MIB_OUTOCTETS should be counted after fragment. This patch reverts commit 2d8dbb04c63e ("snmp: fix OutOctets counter to include forwarded datagrams") and move IPSTATS_MIB_OUTOCTETS to ip_finish_output2 for ipv4. Reviewed-by: Filip Pudak <filip.pudak@windriver.com> Signed-off-by: Heng Guo <heng.guo@windriver.com> Signed-off-by: David S. Miller <davem@davemloft.net> 
commit edf391ff1723 ("snmp: add missing counters for RFC 4293") had
already added OutOctets for RFC 4293. In commit 2d8dbb04c63e ("snmp: fix
OutOctets counter to include forwarded datagrams"), OutOctets was
counted again, but not removed from ip_output().

According to RFC 4293 "3.2.3. IP Statistics Tables",
ipipIfStatsOutTransmits is not equal to ipIfStatsOutForwDatagrams. So
"IPSTATS_MIB_OUTOCTETS must be incremented when incrementing" is not
accurate. And IPSTATS_MIB_OUTOCTETS should be counted after fragment.

This patch reverts commit 2d8dbb04c63e ("snmp: fix OutOctets counter to
include forwarded datagrams") and move IPSTATS_MIB_OUTOCTETS to
ip_finish_output2 for ipv4.

Reviewed-by: Filip Pudak <filip.pudak@windriver.com>
Signed-off-by: Heng Guo <heng.guo@windriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
lwt: Check LWTUNNEL_XMIT_CONTINUE strictly 2023-08-18T14:05:26+00:00 Yan Zhai yan@cloudflare.com 2023-08-18T02:58:14+00:00 a171fbec88a2c730b108c7147ac5e7b2f5a02b47 LWTUNNEL_XMIT_CONTINUE is implicitly assumed in ip(6)_finish_output2, such that any positive return value from a xmit hook could cause unexpected continue behavior, despite that related skb may have been freed. This could be error-prone for future xmit hook ops. One of the possible errors is to return statuses of dst_output directly. To make the code safer, redefine LWTUNNEL_XMIT_CONTINUE value to distinguish from dst_output statuses and check the continue condition explicitly. Fixes: 3a0af8fd61f9 ("bpf: BPF for lightweight tunnel infrastructure") Suggested-by: Dan Carpenter <dan.carpenter@linaro.org> Signed-off-by: Yan Zhai <yan@cloudflare.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Link: https://lore.kernel.org/bpf/96b939b85eda00e8df4f7c080f770970a4c5f698.1692326837.git.yan@cloudflare.com 
LWTUNNEL_XMIT_CONTINUE is implicitly assumed in ip(6)_finish_output2,
such that any positive return value from a xmit hook could cause
unexpected continue behavior, despite that related skb may have been
freed. This could be error-prone for future xmit hook ops. One of the
possible errors is to return statuses of dst_output directly.

To make the code safer, redefine LWTUNNEL_XMIT_CONTINUE value to
distinguish from dst_output statuses and check the continue
condition explicitly.

Fixes: 3a0af8fd61f9 ("bpf: BPF for lightweight tunnel infrastructure")
Suggested-by: Dan Carpenter <dan.carpenter@linaro.org>
Signed-off-by: Yan Zhai <yan@cloudflare.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/96b939b85eda00e8df4f7c080f770970a4c5f698.1692326837.git.yan@cloudflare.com
inet: implement lockless IP_TTL 2023-08-16T10:09:18+00:00 Eric Dumazet edumazet@google.com 2023-08-16T08:15:46+00:00 10f42426e5bcea728d7fae96609b29b4fb1f7518 ip_select_ttl() is racy, because it reads inet->uc_ttl without proper locking. Add READ_ONCE()/WRITE_ONCE() annotations while allowing IP_TTL socket option to be set/read without holding the socket lock. Signed-off-by: Eric Dumazet <edumazet@google.com> Acked-by: Soheil Hassas Yeganeh <soheil@google.com> Reviewed-by: Simon Horman <horms@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net> 
ip_select_ttl() is racy, because it reads inet->uc_ttl
without proper locking.

Add READ_ONCE()/WRITE_ONCE() annotations while
allowing IP_TTL socket option to be set/read without
holding the socket lock.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: Soheil Hassas Yeganeh <soheil@google.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>