summaryrefslogtreecommitdiff
path: root/include/net/ip.h
AgeCommit message (Collapse)Author
2024-04-30inet: introduce dst_rtable() helperEric Dumazet
I added dst_rt6_info() in commit e8dfd42c17fa ("ipv6: introduce dst_rt6_info() helper") This patch does a similar change for IPv4. Instead of (struct rtable *)dst casts, we can use : #define dst_rtable(_ptr) \ container_of_const(_ptr, struct rtable, dst) Patch is smaller than IPv6 one, because IPv4 has skb_rtable() helper. Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: David Ahern <dsahern@kernel.org> Reviewed-by: Sabrina Dubroca <sd@queasysnail.net> Link: https://lore.kernel.org/r/20240429133009.1227754-1-edumazet@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-01-26ipmr: fix kernel panic when forwarding mcast packetsNicolas Dichtel
The stacktrace was: [ 86.305548] BUG: kernel NULL pointer dereference, address: 0000000000000092 [ 86.306815] #PF: supervisor read access in kernel mode [ 86.307717] #PF: error_code(0x0000) - not-present page [ 86.308624] PGD 0 P4D 0 [ 86.309091] Oops: 0000 [#1] PREEMPT SMP NOPTI [ 86.309883] CPU: 2 PID: 3139 Comm: pimd Tainted: G U 6.8.0-6wind-knet #1 [ 86.311027] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.11.1-0-g0551a4be2c-prebuilt.qemu-project.org 04/01/2014 [ 86.312728] RIP: 0010:ip_mr_forward (/build/work/knet/net/ipv4/ipmr.c:1985) [ 86.313399] Code: f9 1f 0f 87 85 03 00 00 48 8d 04 5b 48 8d 04 83 49 8d 44 c5 00 48 8b 40 70 48 39 c2 0f 84 d9 00 00 00 49 8b 46 58 48 83 e0 fe <80> b8 92 00 00 00 00 0f 84 55 ff ff ff 49 83 47 38 01 45 85 e4 0f [ 86.316565] RSP: 0018:ffffad21c0583ae0 EFLAGS: 00010246 [ 86.317497] RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000 [ 86.318596] RDX: ffff9559cb46c000 RSI: 0000000000000000 RDI: 0000000000000000 [ 86.319627] RBP: ffffad21c0583b30 R08: 0000000000000000 R09: 0000000000000000 [ 86.320650] R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000001 [ 86.321672] R13: ffff9559c093a000 R14: ffff9559cc00b800 R15: ffff9559c09c1d80 [ 86.322873] FS: 00007f85db661980(0000) GS:ffff955a79d00000(0000) knlGS:0000000000000000 [ 86.324291] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 86.325314] CR2: 0000000000000092 CR3: 000000002f13a000 CR4: 0000000000350ef0 [ 86.326589] Call Trace: [ 86.327036] <TASK> [ 86.327434] ? show_regs (/build/work/knet/arch/x86/kernel/dumpstack.c:479) [ 86.328049] ? __die (/build/work/knet/arch/x86/kernel/dumpstack.c:421 /build/work/knet/arch/x86/kernel/dumpstack.c:434) [ 86.328508] ? page_fault_oops (/build/work/knet/arch/x86/mm/fault.c:707) [ 86.329107] ? do_user_addr_fault (/build/work/knet/arch/x86/mm/fault.c:1264) [ 86.329756] ? srso_return_thunk (/build/work/knet/arch/x86/lib/retpoline.S:223) [ 86.330350] ? __irq_work_queue_local (/build/work/knet/kernel/irq_work.c:111 (discriminator 1)) [ 86.331013] ? exc_page_fault (/build/work/knet/./arch/x86/include/asm/paravirt.h:693 /build/work/knet/arch/x86/mm/fault.c:1515 /build/work/knet/arch/x86/mm/fault.c:1563) [ 86.331702] ? asm_exc_page_fault (/build/work/knet/./arch/x86/include/asm/idtentry.h:570) [ 86.332468] ? ip_mr_forward (/build/work/knet/net/ipv4/ipmr.c:1985) [ 86.333183] ? srso_return_thunk (/build/work/knet/arch/x86/lib/retpoline.S:223) [ 86.333920] ipmr_mfc_add (/build/work/knet/./include/linux/rcupdate.h:782 /build/work/knet/net/ipv4/ipmr.c:1009 /build/work/knet/net/ipv4/ipmr.c:1273) [ 86.334583] ? __pfx_ipmr_hash_cmp (/build/work/knet/net/ipv4/ipmr.c:363) [ 86.335357] ip_mroute_setsockopt (/build/work/knet/net/ipv4/ipmr.c:1470) [ 86.336135] ? srso_return_thunk (/build/work/knet/arch/x86/lib/retpoline.S:223) [ 86.336854] ? ip_mroute_setsockopt (/build/work/knet/net/ipv4/ipmr.c:1470) [ 86.337679] do_ip_setsockopt (/build/work/knet/net/ipv4/ip_sockglue.c:944) [ 86.338408] ? __pfx_unix_stream_read_actor (/build/work/knet/net/unix/af_unix.c:2862) [ 86.339232] ? srso_return_thunk (/build/work/knet/arch/x86/lib/retpoline.S:223) [ 86.339809] ? aa_sk_perm (/build/work/knet/security/apparmor/include/cred.h:153 /build/work/knet/security/apparmor/net.c:181) [ 86.340342] ip_setsockopt (/build/work/knet/net/ipv4/ip_sockglue.c:1415) [ 86.340859] raw_setsockopt (/build/work/knet/net/ipv4/raw.c:836) [ 86.341408] ? security_socket_setsockopt (/build/work/knet/security/security.c:4561 (discriminator 13)) [ 86.342116] sock_common_setsockopt (/build/work/knet/net/core/sock.c:3716) [ 86.342747] do_sock_setsockopt (/build/work/knet/net/socket.c:2313) [ 86.343363] __sys_setsockopt (/build/work/knet/./include/linux/file.h:32 /build/work/knet/net/socket.c:2336) [ 86.344020] __x64_sys_setsockopt (/build/work/knet/net/socket.c:2340) [ 86.344766] do_syscall_64 (/build/work/knet/arch/x86/entry/common.c:52 /build/work/knet/arch/x86/entry/common.c:83) [ 86.345433] ? srso_return_thunk (/build/work/knet/arch/x86/lib/retpoline.S:223) [ 86.346161] ? syscall_exit_work (/build/work/knet/./include/linux/audit.h:357 /build/work/knet/kernel/entry/common.c:160) [ 86.346938] ? srso_return_thunk (/build/work/knet/arch/x86/lib/retpoline.S:223) [ 86.347657] ? syscall_exit_to_user_mode (/build/work/knet/kernel/entry/common.c:215) [ 86.348538] ? srso_return_thunk (/build/work/knet/arch/x86/lib/retpoline.S:223) [ 86.349262] ? do_syscall_64 (/build/work/knet/./arch/x86/include/asm/cpufeature.h:171 /build/work/knet/arch/x86/entry/common.c:98) [ 86.349971] entry_SYSCALL_64_after_hwframe (/build/work/knet/arch/x86/entry/entry_64.S:129) The original packet in ipmr_cache_report() may be queued and then forwarded with ip_mr_forward(). This last function has the assumption that the skb dst is set. After the below commit, the skb dst is dropped by ipv4_pktinfo_prepare(), which causes the oops. Fixes: bb7403655b3c ("ipmr: support IP_PKTINFO on cache report IGMP msg") Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Link: https://lore.kernel.org/r/20240125141847.1931933-1-nicolas.dichtel@6wind.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-12-15inet: returns a bool from inet_sk_get_local_port_range()Eric Dumazet
Change inet_sk_get_local_port_range() to return a boolean, telling the callers if the port range was provided by IP_LOCAL_PORT_RANGE socket option. Adds documentation while we are at it. Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com> Link: https://lore.kernel.org/r/20231214192939.1962891-2-edumazet@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-12-08Use READ/WRITE_ONCE() for IP local_port_range.David Laight
Commit 227b60f5102cd added a seqlock to ensure that the low and high port numbers were always updated together. This is overkill because the two 16bit port numbers can be held in a u32 and read/written in a single instruction. More recently 91d0b78c5177f added support for finer per-socket limits. The user-supplied value is 'high << 16 | low' but they are held separately and the socket options protected by the socket lock. Use a u32 containing 'high << 16 | low' for both the 'net' and 'sk' fields and use READ_ONCE()/WRITE_ONCE() to ensure both values are always updated together. Change (the now trival) inet_get_local_port_range() to a static inline to optimise the calling code. (In particular avoiding returning integers by reference.) Signed-off-by: David Laight <david.laight@aculab.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Reviewed-by: David Ahern <dsahern@kernel.org> Acked-by: Mat Martineau <martineau@kernel.org> Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com> Link: https://lore.kernel.org/r/4e505d4198e946a8be03fb1b4c3072b0@AcuMS.aculab.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-10-19inet: lock the socket in ip_sock_set_tos()Eric Dumazet
Christoph Paasch reported a panic in TCP stack [1] Indeed, we should not call sk_dst_reset() without holding the socket lock, as __sk_dst_get() callers do not all rely on bare RCU. [1] BUG: kernel NULL pointer dereference, address: 0000000000000000 PGD 12bad6067 P4D 12bad6067 PUD 12bad5067 PMD 0 Oops: 0000 [#1] PREEMPT SMP CPU: 1 PID: 2750 Comm: syz-executor.5 Not tainted 6.6.0-rc4-g7a5720a344e7 #49 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.11.0-2.el7 04/01/2014 RIP: 0010:tcp_get_metrics+0x118/0x8f0 net/ipv4/tcp_metrics.c:321 Code: c7 44 24 70 02 00 8b 03 89 44 24 48 c7 44 24 4c 00 00 00 00 66 c7 44 24 58 02 00 66 ba 02 00 b1 01 89 4c 24 04 4c 89 7c 24 10 <49> 8b 0f 48 8b 89 50 05 00 00 48 89 4c 24 30 33 81 00 02 00 00 69 RSP: 0018:ffffc90000af79b8 EFLAGS: 00010293 RAX: 000000000100007f RBX: ffff88812ae8f500 RCX: ffff88812b5f8f01 RDX: 0000000000000002 RSI: ffffffff8300f080 RDI: 0000000000000002 RBP: 0000000000000002 R08: 0000000000000003 R09: ffffffff8205eca0 R10: 0000000000000002 R11: ffff88812b5f8f00 R12: ffff88812a9e0580 R13: 0000000000000000 R14: ffff88812ae8fbd2 R15: 0000000000000000 FS: 00007f70a006b640(0000) GS:ffff88813bd00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000000 CR3: 000000012bad7003 CR4: 0000000000170ee0 Call Trace: <TASK> tcp_fastopen_cache_get+0x32/0x140 net/ipv4/tcp_metrics.c:567 tcp_fastopen_cookie_check+0x28/0x180 net/ipv4/tcp_fastopen.c:419 tcp_connect+0x9c8/0x12a0 net/ipv4/tcp_output.c:3839 tcp_v4_connect+0x645/0x6e0 net/ipv4/tcp_ipv4.c:323 __inet_stream_connect+0x120/0x590 net/ipv4/af_inet.c:676 tcp_sendmsg_fastopen+0x2d6/0x3a0 net/ipv4/tcp.c:1021 tcp_sendmsg_locked+0x1957/0x1b00 net/ipv4/tcp.c:1073 tcp_sendmsg+0x30/0x50 net/ipv4/tcp.c:1336 __sock_sendmsg+0x83/0xd0 net/socket.c:730 __sys_sendto+0x20a/0x2a0 net/socket.c:2194 __do_sys_sendto net/socket.c:2206 [inline] Fixes: e08d0b3d1723 ("inet: implement lockless IP_TOS") Reported-by: Christoph Paasch <cpaasch@apple.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Link: https://lore.kernel.org/r/20231018090014.345158-1-edumazet@google.com Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2023-10-01inet: implement lockless IP_TOSEric Dumazet
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>
2023-10-01inet: implement lockless IP_MTU_DISCOVEREric Dumazet
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>
2023-09-01ipv4: ignore dst hint for multipath routesSriram Yagnaraman
Route hints when the nexthop is part of a multipath group causes packets in the same receive batch to be sent to the same nexthop irrespective of the multipath hash of the packet. So, do not extract route hint for packets whose destination is part of a multipath group. A new SKB flag IPSKB_MULTIPATH is introduced for this purpose, set the flag when route is looked up in ip_mkroute_input() and use it in ip_extract_route_hint() to check for the existence of the flag. Fixes: 02b24941619f ("ipv4: use dst hint for ipv4 list receive") Signed-off-by: Sriram Yagnaraman <sriram.yagnaraman@est.tech> Reviewed-by: Ido Schimmel <idosch@nvidia.com> Reviewed-by: David Ahern <dsahern@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2023-09-01net: annotate data-races around sk->sk_tsflagsEric Dumazet
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>
2023-08-20ipv4: fix data-races around inet->inet_idEric Dumazet
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 <syzkaller@googlegroups.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: David Ahern <dsahern@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2023-07-29net: annotate data-races around sk->sk_markEric Dumazet
sk->sk_mark is often read while another thread could change the value. Fixes: 4a19ec5800fc ("[NET]: Introducing socket mark socket option.") Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2023-05-25Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netJakub Kicinski
Cross-merge networking fixes after downstream PR. Conflicts: net/ipv4/raw.c 3632679d9e4f ("ipv{4,6}/raw: fix output xfrm lookup wrt protocol") c85be08fc4fa ("raw: Stop using RTO_ONLINK.") https://lore.kernel.org/all/20230525110037.2b532b83@canb.auug.org.au/ Adjacent changes: drivers/net/ethernet/freescale/fec_main.c 9025944fddfe ("net: fec: add dma_wmb to ensure correct descriptor values") 144470c88c5d ("net: fec: using the standard return codes when xdp xmit errors") Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-05-25net: ipv4: use consistent txhash in TIME_WAIT and SYN_RECVAntoine Tenart
When using IPv4/TCP, skb->hash comes from sk->sk_txhash except in TIME_WAIT and SYN_RECV where it's not set in the reply skb from ip_send_unicast_reply. Those packets will have a mismatched hash with others from the same flow as their hashes will be 0. IPv6 does not have the same issue as the hash is set from the socket txhash in those cases. This commits sets the hash in the reply skb from ip_send_unicast_reply, which makes the IPv4 code behaving like IPv6. Signed-off-by: Antoine Tenart <atenart@kernel.org> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2023-05-24raw: Stop using RTO_ONLINK.Guillaume Nault
Use ip_sendmsg_scope() to properly initialise the scope in flowi4_init_output(), instead of overriding tos with the RTO_ONLINK flag. The objective is to eventually remove RTO_ONLINK, which will allow converting .flowi4_tos to dscp_t. The MSG_DONTROUTE and SOCK_LOCALROUTE cases were already handled by raw_sendmsg() (SOCK_LOCALROUTE was handled by the RT_CONN_FLAGS*() macros called by get_rtconn_flags()). However, opt.is_strictroute wasn't taken into account. Therefore, a side effect of this patch is to now honour opt.is_strictroute, and thus align raw_sendmsg() with ping_v4_sendmsg() and udp_sendmsg(). Since raw_sendmsg() was the only user of get_rtconn_flags(), we can now remove this function. Signed-off-by: Guillaume Nault <gnault@redhat.com> Reviewed-by: David Ahern <dsahern@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2023-05-24ping: Stop using RTO_ONLINK.Guillaume Nault
Define a new helper to figure out the correct route scope to use on TX, depending on socket configuration, ancillary data and send flags. Use this new helper to properly initialise the scope in flowi4_init_output(), instead of overriding tos with the RTO_ONLINK flag. The objective is to eventually remove RTO_ONLINK, which will allow converting .flowi4_tos to dscp_t. Signed-off-by: Guillaume Nault <gnault@redhat.com> Reviewed-by: David Ahern <dsahern@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2023-05-23ip: Remove ip_append_page()David Howells
ip_append_page() is no longer used with the removal of udp_sendpage(), so remove it. Signed-off-by: David Howells <dhowells@redhat.com> cc: Willem de Bruijn <willemdebruijn.kernel@gmail.com> cc: David Ahern <dsahern@kernel.org> cc: Jens Axboe <axboe@kernel.dk> cc: Matthew Wilcox <willy@infradead.org> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-05-23ipv{4,6}/raw: fix output xfrm lookup wrt protocolNicolas Dichtel
With a raw socket bound to IPPROTO_RAW (ie with hdrincl enabled), the protocol field of the flow structure, build by raw_sendmsg() / rawv6_sendmsg()), is set to IPPROTO_RAW. This breaks the ipsec policy lookup when some policies are defined with a protocol in the selector. For ipv6, the sin6_port field from 'struct sockaddr_in6' could be used to specify the protocol. Just accept all values for IPPROTO_RAW socket. For ipv4, the sin_port field of 'struct sockaddr_in' could not be used without breaking backward compatibility (the value of this field was never checked). Let's add a new kind of control message, so that the userland could specify which protocol is used. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") CC: stable@vger.kernel.org Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com> Link: https://lore.kernel.org/r/20230522120820.1319391-1-nicolas.dichtel@6wind.com Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2023-01-25inet: Add IP_LOCAL_PORT_RANGE socket optionJakub Sitnicki
Users who want to share a single public IP address for outgoing connections between several hosts traditionally reach for SNAT. However, SNAT requires state keeping on the node(s) performing the NAT. A stateless alternative exists, where a single IP address used for egress can be shared between several hosts by partitioning the available ephemeral port range. In such a setup: 1. Each host gets assigned a disjoint range of ephemeral ports. 2. Applications open connections from the host-assigned port range. 3. Return traffic gets routed to the host based on both, the destination IP and the destination port. An application which wants to open an outgoing connection (connect) from a given port range today can choose between two solutions: 1. Manually pick the source port by bind()'ing to it before connect()'ing the socket. This approach has a couple of downsides: a) Search for a free port has to be implemented in the user-space. If the chosen 4-tuple happens to be busy, the application needs to retry from a different local port number. Detecting if 4-tuple is busy can be either easy (TCP) or hard (UDP). In TCP case, the application simply has to check if connect() returned an error (EADDRNOTAVAIL). That is assuming that the local port sharing was enabled (REUSEADDR) by all the sockets. # Assume desired local port range is 60_000-60_511 s = socket(AF_INET, SOCK_STREAM) s.setsockopt(SOL_SOCKET, SO_REUSEADDR, 1) s.bind(("192.0.2.1", 60_000)) s.connect(("1.1.1.1", 53)) # Fails only if 192.0.2.1:60000 -> 1.1.1.1:53 is busy # Application must retry with another local port In case of UDP, the network stack allows binding more than one socket to the same 4-tuple, when local port sharing is enabled (REUSEADDR). Hence detecting the conflict is much harder and involves querying sock_diag and toggling the REUSEADDR flag [1]. b) For TCP, bind()-ing to a port within the ephemeral port range means that no connecting sockets, that is those which leave it to the network stack to find a free local port at connect() time, can use the this port. IOW, the bind hash bucket tb->fastreuse will be 0 or 1, and the port will be skipped during the free port search at connect() time. 2. Isolate the app in a dedicated netns and use the use the per-netns ip_local_port_range sysctl to adjust the ephemeral port range bounds. The per-netns setting affects all sockets, so this approach can be used only if: - there is just one egress IP address, or - the desired egress port range is the same for all egress IP addresses used by the application. For TCP, this approach avoids the downsides of (1). Free port search and 4-tuple conflict detection is done by the network stack: system("sysctl -w net.ipv4.ip_local_port_range='60000 60511'") s = socket(AF_INET, SOCK_STREAM) s.setsockopt(SOL_IP, IP_BIND_ADDRESS_NO_PORT, 1) s.bind(("192.0.2.1", 0)) s.connect(("1.1.1.1", 53)) # Fails if all 4-tuples 192.0.2.1:60000-60511 -> 1.1.1.1:53 are busy For UDP this approach has limited applicability. Setting the IP_BIND_ADDRESS_NO_PORT socket option does not result in local source port being shared with other connected UDP sockets. Hence relying on the network stack to find a free source port, limits the number of outgoing UDP flows from a single IP address down to the number of available ephemeral ports. To put it another way, partitioning the ephemeral port range between hosts using the existing Linux networking API is cumbersome. To address this use case, add a new socket option at the SOL_IP level, named IP_LOCAL_PORT_RANGE. The new option can be used to clamp down the ephemeral port range for each socket individually. The option can be used only to narrow down the per-netns local port range. If the per-socket range lies outside of the per-netns range, the latter takes precedence. UAPI-wise, the low and high range bounds are passed to the kernel as a pair of u16 values in host byte order packed into a u32. This avoids pointer passing. PORT_LO = 40_000 PORT_HI = 40_511 s = socket(AF_INET, SOCK_STREAM) v = struct.pack("I", PORT_HI << 16 | PORT_LO) s.setsockopt(SOL_IP, IP_LOCAL_PORT_RANGE, v) s.bind(("127.0.0.1", 0)) s.getsockname() # Local address between ("127.0.0.1", 40_000) and ("127.0.0.1", 40_511), # if there is a free port. EADDRINUSE otherwise. [1] https://github.com/cloudflare/cloudflare-blog/blob/232b432c1d57/2022-02-connectx/connectx.py#L116 Reviewed-by: Marek Majkowski <marek@cloudflare.com> Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com> Signed-off-by: Jakub Sitnicki <jakub@cloudflare.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-11-17net: use struct_group to copy ip/ipv6 header addressesHangbin Liu
kernel test robot reported warnings when build bonding module with make W=1 O=build_dir ARCH=x86_64 SHELL=/bin/bash drivers/net/bonding/: from ../drivers/net/bonding/bond_main.c:35: In function ‘fortify_memcpy_chk’, inlined from ‘iph_to_flow_copy_v4addrs’ at ../include/net/ip.h:566:2, inlined from ‘bond_flow_ip’ at ../drivers/net/bonding/bond_main.c:3984:3: ../include/linux/fortify-string.h:413:25: warning: call to ‘__read_overflow2_field’ declared with attribute warning: detected read beyond size of f ield (2nd parameter); maybe use struct_group()? [-Wattribute-warning] 413 | __read_overflow2_field(q_size_field, size); | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ In function ‘fortify_memcpy_chk’, inlined from ‘iph_to_flow_copy_v6addrs’ at ../include/net/ipv6.h:900:2, inlined from ‘bond_flow_ip’ at ../drivers/net/bonding/bond_main.c:3994:3: ../include/linux/fortify-string.h:413:25: warning: call to ‘__read_overflow2_field’ declared with attribute warning: detected read beyond size of f ield (2nd parameter); maybe use struct_group()? [-Wattribute-warning] 413 | __read_overflow2_field(q_size_field, size); | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ This is because we try to copy the whole ip/ip6 address to the flow_key, while we only point the to ip/ip6 saddr. Note that since these are UAPI headers, __struct_group() is used to avoid the compiler warnings. Reported-by: kernel test robot <lkp@intel.com> Fixes: c3f8324188fa ("net: Add full IPv6 addresses to flow_keys") Signed-off-by: Hangbin Liu <liuhangbin@gmail.com> Link: https://lore.kernel.org/r/20221115142400.1204786-1-liuhangbin@gmail.com Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2022-09-02bpf: Change bpf_getsockopt(SOL_IP) to reuse do_ip_getsockopt()Martin KaFai Lau
This patch changes bpf_getsockopt(SOL_IP) to reuse do_ip_getsockopt() and remove the duplicated code. Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org> Link: https://lore.kernel.org/r/20220902002925.2895416-1-kafai@fb.com Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-08-18bpf: Change bpf_setsockopt(SOL_IP) to reuse do_ip_setsockopt()Martin KaFai Lau
After the prep work in the previous patches, this patch removes the dup code from bpf_setsockopt(SOL_IP) and reuses the implementation in do_ip_setsockopt(). The existing optname white-list is refactored into a new function sol_ip_setsockopt(). NOTE, the current bpf_setsockopt(IP_TOS) is quite different from the the do_ip_setsockopt(IP_TOS). For example, it does not take the INET_ECN_MASK into the account for tcp and also does not adjust sk->sk_priority. It looks like the current bpf_setsockopt(IP_TOS) was referencing the IPV6_TCLASS implementation instead of IP_TOS. This patch tries to rectify that by using the do_ip_setsockopt(IP_TOS). While this is a behavior change, the do_ip_setsockopt(IP_TOS) behavior is arguably what the user is expecting. At least, the INET_ECN_MASK bits should be masked out for tcp. Reviewed-by: Stanislav Fomichev <sdf@google.com> Signed-off-by: Martin KaFai Lau <kafai@fb.com> Link: https://lore.kernel.org/r/20220817061826.4180990-1-kafai@fb.com Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-07-20ip: Fix data-races around sysctl_ip_prot_sock.Kuniyuki Iwashima
sysctl_ip_prot_sock is accessed concurrently, and there is always a chance of data-race. So, all readers and writers need some basic protection to avoid load/store-tearing. Fixes: 4548b683b781 ("Introduce a sysctl that modifies the value of PROT_SOCK.") Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2022-07-15ip: Fix a data-race around sysctl_fwmark_reflect.Kuniyuki Iwashima
While reading sysctl_fwmark_reflect, it can be changed concurrently. Thus, we need to add READ_ONCE() to its reader. Fixes: e110861f8609 ("net: add a sysctl to reflect the fwmark on replies") Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2022-07-15ip: Fix data-races around sysctl_ip_fwd_use_pmtu.Kuniyuki Iwashima
While reading sysctl_ip_fwd_use_pmtu, it can be changed concurrently. Thus, we need to add READ_ONCE() to its readers. Fixes: f87c10a8aa1e ("ipv4: introduce ip_dst_mtu_maybe_forward and protect forwarding path against pmtu spoofing") Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2022-05-19Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netJakub Kicinski
drivers/net/ethernet/mellanox/mlx5/core/main.c b33886971dbc ("net/mlx5: Initialize flow steering during driver probe") 40379a0084c2 ("net/mlx5_fpga: Drop INNOVA TLS support") f2b41b32cde8 ("net/mlx5: Remove ipsec_ops function table") https://lore.kernel.org/all/20220519040345.6yrjromcdistu7vh@sx1/ 16d42d313350 ("net/mlx5: Drain fw_reset when removing device") 8324a02c342a ("net/mlx5: Add exit route when waiting for FW") https://lore.kernel.org/all/20220519114119.060ce014@canb.auug.org.au/ tools/testing/selftests/net/mptcp/mptcp_join.sh e274f7154008 ("selftests: mptcp: add subflow limits test-cases") b6e074e171bc ("selftests: mptcp: add infinite map testcase") 5ac1d2d63451 ("selftests: mptcp: Add tests for userspace PM type") https://lore.kernel.org/all/20220516111918.366d747f@canb.auug.org.au/ net/mptcp/options.c ba2c89e0ea74 ("mptcp: fix checksum byte order") 1e39e5a32ad7 ("mptcp: infinite mapping sending") ea66758c1795 ("tcp: allow MPTCP to update the announced window") https://lore.kernel.org/all/20220519115146.751c3a37@canb.auug.org.au/ net/mptcp/pm.c 95d686517884 ("mptcp: fix subflow accounting on close") 4d25247d3ae4 ("mptcp: bypass in-kernel PM restrictions for non-kernel PMs") https://lore.kernel.org/all/20220516111435.72f35dca@canb.auug.org.au/ net/mptcp/subflow.c ae66fb2ba6c3 ("mptcp: Do TCP fallback on early DSS checksum failure") 0348c690ed37 ("mptcp: add the fallback check") f8d4bcacff3b ("mptcp: infinite mapping receiving") https://lore.kernel.org/all/20220519115837.380bb8d4@canb.auug.org.au/ Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-05-16net: annotate races around sk->sk_bound_dev_ifEric Dumazet
UDP sendmsg() is lockless, and reads sk->sk_bound_dev_if while this field can be changed by another thread. Adds minimal annotations to avoid KCSAN splats for UDP. Following patches will add more annotations to potential lockless readers. BUG: KCSAN: data-race in __ip6_datagram_connect / udpv6_sendmsg write to 0xffff888136d47a94 of 4 bytes by task 7681 on cpu 0: __ip6_datagram_connect+0x6e2/0x930 net/ipv6/datagram.c:221 ip6_datagram_connect+0x2a/0x40 net/ipv6/datagram.c:272 inet_dgram_connect+0x107/0x190 net/ipv4/af_inet.c:576 __sys_connect_file net/socket.c:1900 [inline] __sys_connect+0x197/0x1b0 net/socket.c:1917 __do_sys_connect net/socket.c:1927 [inline] __se_sys_connect net/socket.c:1924 [inline] __x64_sys_connect+0x3d/0x50 net/socket.c:1924 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x2b/0x50 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae read to 0xffff888136d47a94 of 4 bytes by task 7670 on cpu 1: udpv6_sendmsg+0xc60/0x16e0 net/ipv6/udp.c:1436 inet6_sendmsg+0x5f/0x80 net/ipv6/af_inet6.c:652 sock_sendmsg_nosec net/socket.c:705 [inline] sock_sendmsg net/socket.c:725 [inline] ____sys_sendmsg+0x39a/0x510 net/socket.c:2413 ___sys_sendmsg net/socket.c:2467 [inline] __sys_sendmmsg+0x267/0x4c0 net/socket.c:2553 __do_sys_sendmmsg net/socket.c:2582 [inline] __se_sys_sendmmsg net/socket.c:2579 [inline] __x64_sys_sendmmsg+0x53/0x60 net/socket.c:2579 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x2b/0x50 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae value changed: 0x00000000 -> 0xffffff9b Reported by Kernel Concurrency Sanitizer on: CPU: 1 PID: 7670 Comm: syz-executor.3 Tainted: G W 5.18.0-rc1-syzkaller-dirty #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 I chose to not add Fixes: tag because race has minor consequences and stable teams busy enough. Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: syzbot <syzkaller@googlegroups.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2022-05-16xfrm: fix "disable_policy" flag use when arriving from different devicesEyal Birger
In IPv4 setting the "disable_policy" flag on a device means no policy should be enforced for traffic originating from the device. This was implemented by seting the DST_NOPOLICY flag in the dst based on the originating device. However, dsts are cached in nexthops regardless of the originating devices, in which case, the DST_NOPOLICY flag value may be incorrect. Consider the following setup: +------------------------------+ | ROUTER | +-------------+ | +-----------------+ | | ipsec src |----|-|ipsec0 | | +-------------+ | |disable_policy=0 | +----+ | | +-----------------+ |eth1|-|----- +-------------+ | +-----------------+ +----+ | | noipsec src |----|-|eth0 | | +-------------+ | |disable_policy=1 | | | +-----------------+ | +------------------------------+ Where ROUTER has a default route towards eth1. dst entries for traffic arriving from eth0 would have DST_NOPOLICY and would be cached and therefore can be reused by traffic originating from ipsec0, skipping policy check. Fix by setting a IPSKB_NOPOLICY flag in IPCB and observing it instead of the DST in IN/FWD IPv4 policy checks. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Reported-by: Shmulik Ladkani <shmulik.ladkani@gmail.com> Signed-off-by: Eyal Birger <eyal.birger@gmail.com> Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
2022-01-31ipv4: Make ip_idents_reserve staticDavid Ahern
ip_idents_reserve is only used in net/ipv4/route.c. Make it static and remove the export. Signed-off-by: David Ahern <dsahern@kernel.org> Cc: Eric Dumazet <edumazet@google.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2022-01-29ipv4: drop fragmentation code from ip_options_build()Jakub Kicinski
Since v2.5.44 and addition of ip_options_fragment() ip_options_build() does not render headers for fragments directly. @is_frag is always 0. Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2022-01-27ipv4: avoid using shared IP generator for connected socketsEric Dumazet
ip_select_ident_segs() has been very conservative about using the connected socket private generator only for packets with IP_DF set, claiming it was needed for some VJ compression implementations. As mentioned in this referenced document, this can be abused. (Ref: Off-Path TCP Exploits of the Mixed IPID Assignment) Before switching to pure random IPID generation and possibly hurt some workloads, lets use the private inet socket generator. Not only this will remove one vulnerability, this will also improve performance of TCP flows using pmtudisc==IP_PMTUDISC_DONT Fixes: 73f156a6e8c1 ("inetpeer: get rid of ip_id_count") Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: David Ahern <dsahern@kernel.org> Reported-by: Ray Che <xijiache@gmail.com> Cc: Willy Tarreau <w@1wt.eu> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-11-20ipv4: Exposing __ip_sock_set_tos() in ip.hPoorva Sonparote
Making the static function __ip_sock_set_tos() from net/ipv4/ip_sockglue.c accessible by declaring it in include/net/ip.h The reason for doing this is to use this function to set IP_TOS value in mptcp_setsockopt() without the lock. Signed-off-by: Poorva Sonparote <psonparo@redhat.com> Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-11-16net: move gro definitions to include/net/gro.hEric Dumazet
include/linux/netdevice.h became too big, move gro stuff into include/net/gro.h Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-10-25ipv4: guard IP_MINTTL with a static keyEric Dumazet
RFC 5082 IP_MINTTL option is rarely used on hosts. Add a static key to remove from TCP fast path useless code, and potential cache line miss to fetch inet_sk(sk)->min_ttl Note that once ip4_min_ttl static key has been enabled, it stays enabled until next boot. Signed-off-by: Eric Dumazet <edumazet@google.com> Acked-by: Soheil Hassas Yeganeh <soheil@google.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-09-30net: snmp: inline snmp_get_cpu_field()Eric Dumazet
This trivial function is called ~90,000 times on 256 cpus hosts, when reading /proc/net/netstat. And this number keeps inflating. Inlining it saves many cycles. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-07-21net: ipv4: Consolidate ipv4_mtu and ip_dst_mtu_maybe_forwardVadim Fedorenko
Consolidate IPv4 MTU code the same way it is done in IPv6 to have code aligned in both address families Signed-off-by: Vadim Fedorenko <vfedorenko@novek.ru> Reviewed-by: David Ahern <dsahern@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-28net: lwtunnel: handle MTU calculation in forwadingVadim Fedorenko
Commit 14972cbd34ff ("net: lwtunnel: Handle fragmentation") moved fragmentation logic away from lwtunnel by carry encap headroom and use it in output MTU calculation. But the forwarding part was not covered and created difference in MTU for output and forwarding and further to silent drops on ipv4 forwarding path. Fix it by taking into account lwtunnel encap headroom. The same commit also introduced difference in how to treat RTAX_MTU in IPv4 and IPv6 where latter explicitly removes lwtunnel encap headroom from route MTU. Make IPv4 version do the same. Fixes: 14972cbd34ff ("net: lwtunnel: Handle fragmentation") Suggested-by: David Ahern <dsahern@gmail.com> Signed-off-by: Vadim Fedorenko <vfedorenko@novek.ru> Reviewed-by: David Ahern <dsahern@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-11-10inet: constify inet_sdif() argumentEric Dumazet
inet_sdif() does not modify the skb. This will permit propagating the const qualifier in udp{4|6}_lib_lookup_skb() functions. Signed-off-by: Eric Dumazet <edumazet@google.com> Acked-by: Alexander Lobakin <alobakin@pm.me> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2020-10-05Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netDavid S. Miller
Rejecting non-native endian BTF overlapped with the addition of support for it. The rest were more simple overlapping changes, except the renesas ravb binding update, which had to follow a file move as well as a YAML conversion. Signed-off-by: David S. Miller <davem@davemloft.net>
2020-09-24net/ipv4: always honour route mtu during forwardingMaciej Żenczykowski
Documentation/networking/ip-sysctl.txt:46 says: ip_forward_use_pmtu - BOOLEAN By default we don't trust protocol path MTUs while forwarding because they could be easily forged and can lead to unwanted fragmentation by the router. You only need to enable this if you have user-space software which tries to discover path mtus by itself and depends on the kernel honoring this information. This is normally not the case. Default: 0 (disabled) Possible values: 0 - disabled 1 - enabled Which makes it pretty clear that setting it to 1 is a potential security/safety/DoS issue, and yet it is entirely reasonable to want forwarded traffic to honour explicitly administrator configured route mtus (instead of defaulting to device mtu). Indeed, I can't think of a single reason why you wouldn't want to. Since you configured a route mtu you probably know better... It is pretty common to have a higher device mtu to allow receiving large (jumbo) frames, while having some routes via that interface (potentially including the default route to the internet) specify a lower mtu. Note that ipv6 forwarding uses device mtu unless the route is locked (in which case it will use the route mtu). This approach is not usable for IPv4 where an 'mtu lock' on a route also has the side effect of disabling TCP path mtu discovery via disabling the IPv4 DF (don't frag) bit on all outgoing frames. I'm not aware of a way to lock a route from an IPv6 RA, so that also potentially seems wrong. Signed-off-by: Maciej Żenczykowski <maze@google.com> Cc: Eric Dumazet <edumazet@google.com> Cc: Willem de Bruijn <willemb@google.com> Cc: Lorenzo Colitti <lorenzo@google.com> Cc: Sunmeet Gill (Sunny) <sgill@quicinc.com> Cc: Vinay Paradkar <vparadka@qti.qualcomm.com> Cc: Tyler Wear <twear@quicinc.com> Cc: David Ahern <dsahern@kernel.org> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-09-10ip: pass tos into ip_build_and_send_pkt()Wei Wang
This commit adds tos as a new passed in parameter to ip_build_and_send_pkt() which will be used in the later commit. This is a pure restructure and does not have any functional change. Signed-off-by: Wei Wang <weiwan@google.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-07-24net: pass a sockptr_t into ->setsockoptChristoph Hellwig
Rework the remaining setsockopt code to pass a sockptr_t instead of a plain user pointer. This removes the last remaining set_fs(KERNEL_DS) outside of architecture specific code. Signed-off-by: Christoph Hellwig <hch@lst.de> Acked-by: Stefan Schmidt <stefan@datenfreihafen.org> [ieee802154] Acked-by: Matthieu Baerts <matthieu.baerts@tessares.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-07-24net/ipv4: merge ip_options_get and ip_options_get_from_userChristoph Hellwig
Use the sockptr_t type to merge the versions. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-07-19net/ipv4: remove compat_ip_{get,set}sockoptChristoph Hellwig
Handle the few cases that need special treatment in-line using in_compat_syscall(). Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-06-20tcp: remove indirect calls for icsk->icsk_af_ops->queue_xmitEric Dumazet
Mitigate RETPOLINE costs in __tcp_transmit_skb() by using INDIRECT_CALL_INET() wrapper. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-05-28ipv4: add ip_sock_set_pktinfoChristoph Hellwig
Add a helper to directly set the IP_PKTINFO sockopt from kernel space without going through a fake uaccess. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-05-28ipv4: add ip_sock_set_mtu_discoverChristoph Hellwig
Add a helper to directly set the IP_MTU_DISCOVER sockopt from kernel space without going through a fake uaccess. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: David Howells <dhowells@redhat.com> [rxrpc bits] Signed-off-by: David S. Miller <davem@davemloft.net>
2020-05-28ipv4: add ip_sock_set_recverrChristoph Hellwig
Add a helper to directly set the IP_RECVERR sockopt from kernel space without going through a fake uaccess. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: David Howells <dhowells@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-05-28ipv4: add ip_sock_set_freebindChristoph Hellwig
Add a helper to directly set the IP_FREEBIND sockopt from kernel space without going through a fake uaccess. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-05-28ipv4: add ip_sock_set_tosChristoph Hellwig
Add a helper to directly set the IP_TOS sockopt from kernel space without going through a fake uaccess. Signed-off-by: Christoph Hellwig <hch@lst.de> Acked-by: Sagi Grimberg <sagi@grimberg.me> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-12-07inet: protect against too small mtu values.Eric Dumazet
syzbot was once again able to crash a host by setting a very small mtu on loopback device. Let's make inetdev_valid_mtu() available in include/net/ip.h, and use it in ip_setup_cork(), so that we protect both ip_append_page() and __ip_append_data() Also add a READ_ONCE() when the device mtu is read. Pairs this lockless read with one WRITE_ONCE() in __dev_set_mtu(), even if other code paths might write over this field. Add a big comment in include/linux/netdevice.h about dev->mtu needing READ_ONCE()/WRITE_ONCE() annotations. Hopefully we will add the missing ones in followup patches. [1] refcount_t: saturated; leaking memory. WARNING: CPU: 0 PID: 9464 at lib/refcount.c:22 refcount_warn_saturate+0x138/0x1f0 lib/refcount.c:22 Kernel panic - not syncing: panic_on_warn set ... CPU: 0 PID: 9464 Comm: syz-executor850 Not tainted 5.4.0-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x197/0x210 lib/dump_stack.c:118 panic+0x2e3/0x75c kernel/panic.c:221 __warn.cold+0x2f/0x3e kernel/panic.c:582 report_bug+0x289/0x300 lib/bug.c:195 fixup_bug arch/x86/kernel/traps.c:174 [inline] fixup_bug arch/x86/kernel/traps.c:169 [inline] do_error_trap+0x11b/0x200 arch/x86/kernel/traps.c:267 do_invalid_op+0x37/0x50 arch/x86/kernel/traps.c:286 invalid_op+0x23/0x30 arch/x86/entry/entry_64.S:1027 RIP: 0010:refcount_warn_saturate+0x138/0x1f0 lib/refcount.c:22 Code: 06 31 ff 89 de e8 c8 f5 e6 fd 84 db 0f 85 6f ff ff ff e8 7b f4 e6 fd 48 c7 c7 e0 71 4f 88 c6 05 56 a6 a4 06 01 e8 c7 a8 b7 fd <0f> 0b e9 50 ff ff ff e8 5c f4 e6 fd 0f b6 1d 3d a6 a4 06 31 ff 89 RSP: 0018:ffff88809689f550 EFLAGS: 00010286 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000 RDX: 0000000000000000 RSI: ffffffff815e4336 RDI: ffffed1012d13e9c RBP: ffff88809689f560 R08: ffff88809c50a3c0 R09: fffffbfff15d31b1 R10: fffffbfff15d31b0 R11: ffffffff8ae98d87 R12: 0000000000000001 R13: 0000000000040100 R14: ffff888099041104 R15: ffff888218d96e40 refcount_add include/linux/refcount.h:193 [inline] skb_set_owner_w+0x2b6/0x410 net/core/sock.c:1999 sock_wmalloc+0xf1/0x120 net/core/sock.c:2096 ip_append_page+0x7ef/0x1190 net/ipv4/ip_output.c:1383 udp_sendpage+0x1c7/0x480 net/ipv4/udp.c:1276 inet_sendpage+0xdb/0x150 net/ipv4/af_inet.c:821 kernel_sendpage+0x92/0xf0 net/socket.c:3794 sock_sendpage+0x8b/0xc0 net/socket.c:936 pipe_to_sendpage+0x2da/0x3c0 fs/splice.c:458 splice_from_pipe_feed fs/splice.c:512 [inline] __splice_from_pipe+0x3ee/0x7c0 fs/splice.c:636 splice_from_pipe+0x108/0x170 fs/splice.c:671 generic_splice_sendpage+0x3c/0x50 fs/splice.c:842 do_splice_from fs/splice.c:861 [inline] direct_splice_actor+0x123/0x190 fs/splice.c:1035 splice_direct_to_actor+0x3b4/0xa30 fs/splice.c:990 do_splice_direct+0x1da/0x2a0 fs/splice.c:1078 do_sendfile+0x597/0xd00 fs/read_write.c:1464 __do_sys_sendfile64 fs/read_write.c:1525 [inline] __se_sys_sendfile64 fs/read_write.c:1511 [inline] __x64_sys_sendfile64+0x1dd/0x220 fs/read_write.c:1511 do_syscall_64+0xfa/0x790 arch/x86/entry/common.c:294 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x441409 Code: e8 ac e8 ff ff 48 83 c4 18 c3 0f 1f 80 00 00 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 eb 08 fc ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007fffb64c4f78 EFLAGS: 00000246 ORIG_RAX: 0000000000000028 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000441409 RDX: 0000000000000000 RSI: 0000000000000006 RDI: 0000000000000005 RBP: 0000000000073b8a R08: 0000000000000010 R09: 0000000000000010 R10: 0000000000010001 R11: 0000000000000246 R12: 0000000000402180 R13: 0000000000402210 R14: 0000000000000000 R15: 0000000000000000 Kernel Offset: disabled Rebooting in 86400 seconds.. Fixes: 1470ddf7f8ce ("inet: Remove explicit write references to sk/inet in ip_append_data") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: syzbot <syzkaller@googlegroups.com> Signed-off-by: David S. Miller <davem@davemloft.net>