summaryrefslogtreecommitdiff
path: root/net/ipv4
AgeCommit message (Collapse)AuthorFilesLines
2022-10-24net-next: Fix IP_UNICAST_IF option behavior for connected socketsRichard Gobert1-0/+2
[ Upstream commit 0e4d354762cefd3e16b4cff8988ff276e45effc4 ] 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 <richardbgobert@gmail.com> Reviewed-by: David Ahern <dsahern@kernel.org> Link: https://lore.kernel.org/r/20220829111554.GA1771@debian Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-10-24tcp: annotate data-race around tcp_md5sig_pool_populatedEric Dumazet1-4/+10
[ Upstream commit aacd467c0a576e5e44d2de4205855dc0fe43f6fb ] tcp_md5sig_pool_populated can be read while another thread changes its value. The race has no consequence because allocations are protected with tcp_md5sig_mutex. This patch adds READ_ONCE() and WRITE_ONCE() to document the race and silence KCSAN. Reported-by: Abhishek Shah <abhishek.shah@columbia.edu> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-10-24once: add DO_ONCE_SLOW() for sleepable contextsEric Dumazet1-2/+2
[ Upstream commit 62c07983bef9d3e78e71189441e1a470f0d1e653 ] Christophe Leroy reported a ~80ms latency spike happening at first TCP connect() time. This is because __inet_hash_connect() uses get_random_once() to populate a perturbation table which became quite big after commit 4c2c8f03a5ab ("tcp: increase source port perturb table to 2^16") get_random_once() uses DO_ONCE(), which block hard irqs for the duration of the operation. This patch adds DO_ONCE_SLOW() which uses a mutex instead of a spinlock for operations where we prefer to stay in process context. Then __inet_hash_connect() can use get_random_slow_once() to populate its perturbation table. Fixes: 4c2c8f03a5ab ("tcp: increase source port perturb table to 2^16") Fixes: 190cc82489f4 ("tcp: change source port randomizarion at connect() time") Reported-by: Christophe Leroy <christophe.leroy@csgroup.eu> Link: https://lore.kernel.org/netdev/CANn89iLAEYBaoYajy0Y9UmGFff5GPxDUoG-ErVB2jDdRNQ5Tug@mail.gmail.com/T/#t Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Willy Tarreau <w@1wt.eu> Tested-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-10-24tcp: fix tcp_cwnd_validate() to not forget is_cwnd_limitedNeal Cardwell2-7/+14
[ Upstream commit f4ce91ce12a7c6ead19b128ffa8cff6e3ded2a14 ] This commit fixes a bug in the tracking of max_packets_out and is_cwnd_limited. This bug can cause the connection to fail to remember that is_cwnd_limited is true, causing the connection to fail to grow cwnd when it should, causing throughput to be lower than it should be. The following event sequence is an example that triggers the bug: (a) The connection is cwnd_limited, but packets_out is not at its peak due to TSO deferral deciding not to send another skb yet. In such cases the connection can advance max_packets_seq and set tp->is_cwnd_limited to true and max_packets_out to a small number. (b) Then later in the round trip the connection is pacing-limited (not cwnd-limited), and packets_out is larger. In such cases the connection would raise max_packets_out to a bigger number but (unexpectedly) flip tp->is_cwnd_limited from true to false. This commit fixes that bug. One straightforward fix would be to separately track (a) the next window after max_packets_out reaches a maximum, and (b) the next window after tp->is_cwnd_limited is set to true. But this would require consuming an extra u32 sequence number. Instead, to save space we track only the most important information. Specifically, we track the strongest available signal of the degree to which the cwnd is fully utilized: (1) If the connection is cwnd-limited then we remember that fact for the current window. (2) If the connection not cwnd-limited then we track the maximum number of outstanding packets in the current window. In particular, note that the new logic cannot trigger the buggy (a)/(b) sequence above because with the new logic a condition where tp->packets_out > tp->max_packets_out can only trigger an update of tp->is_cwnd_limited if tp->is_cwnd_limited is false. This first showed up in a testing of a BBRv2 dev branch, but this buggy behavior highlighted a general issue with the tcp_cwnd_validate() logic that can cause cwnd to fail to increase at the proper rate for any TCP congestion control, including Reno or CUBIC. Fixes: ca8a22634381 ("tcp: make cwnd-limited checks measurement-based, and gentler") Signed-off-by: Neal Cardwell <ncardwell@google.com> Signed-off-by: Kevin(Yudong) Yang <yyd@google.com> Signed-off-by: Yuchung Cheng <ycheng@google.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-10-24netfilter: nft_fib: Fix for rpath check with VRF devicesPhil Sutter1-0/+3
[ Upstream commit 2a8a7c0eaa8747c16aa4a48d573aa920d5c00a5c ] Analogous to commit b575b24b8eee3 ("netfilter: Fix rpfilter dropping vrf packets by mistake") but for nftables fib expression: Add special treatment of VRF devices so that typical reverse path filtering via 'fib saddr . iif oif' expression works as expected. Fixes: f6d0cbcf09c50 ("netfilter: nf_tables: add fib expression") Signed-off-by: Phil Sutter <phil@nwl.cc> Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-10-24esp: choose the correct inner protocol for GSO on inter address family tunnelsSabrina Dubroca1-1/+4
[ Upstream commit 26dbd66eab8080be51759e48280da04015221e22 ] Commit 23c7f8d7989e ("net: Fix esp GSO on inter address family tunnels.") is incomplete. It passes to skb_eth_gso_segment the protocol for the outer IP version, instead of the inner IP version, so we end up calling inet_gso_segment on an inner IPv6 packet and ipv6_gso_segment on an inner IPv4 packet and the packets are dropped. This patch completes the fix by selecting the correct protocol based on the inner mode's family. Fixes: c35fe4106b92 ("xfrm: Add mode handlers for IPsec on layer 2") Signed-off-by: Sabrina Dubroca <sd@queasysnail.net> Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-09-23net: Find dst with sk's xfrm policy not ctl_sksewookseo2-1/+3
commit e22aa14866684f77b4f6b6cae98539e520ddb731 upstream. If we set XFRM security policy by calling setsockopt with option IPV6_XFRM_POLICY, the policy will be stored in 'sock_policy' in 'sock' struct. However tcp_v6_send_response doesn't look up dst_entry with the actual socket but looks up with tcp control socket. This may cause a problem that a RST packet is sent without ESP encryption & peer's TCP socket can't receive it. This patch will make the function look up dest_entry with actual socket, if the socket has XFRM policy(sock_policy), so that the TCP response packet via this function can be encrypted, & aligned on the encrypted TCP socket. Tested: We encountered this problem when a TCP socket which is encrypted in ESP transport mode encryption, receives challenge ACK at SYN_SENT state. After receiving challenge ACK, TCP needs to send RST to establish the socket at next SYN try. But the RST was not encrypted & peer TCP socket still remains on ESTABLISHED state. So we verified this with test step as below. [Test step] 1. Making a TCP state mismatch between client(IDLE) & server(ESTABLISHED). 2. Client tries a new connection on the same TCP ports(src & dst). 3. Server will return challenge ACK instead of SYN,ACK. 4. Client will send RST to server to clear the SOCKET. 5. Client will retransmit SYN to server on the same TCP ports. [Expected result] The TCP connection should be established. Cc: Maciej Żenczykowski <maze@google.com> Cc: Eric Dumazet <edumazet@google.com> Cc: Steffen Klassert <steffen.klassert@secunet.com> Cc: Sehee Lee <seheele@google.com> Signed-off-by: Sewook Seo <sewookseo@google.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-09-15tcp: fix early ETIMEDOUT after spurious non-SACK RTONeal Cardwell1-7/+18
[ Upstream commit 686dc2db2a0fdc1d34b424ec2c0a735becd8d62b ] Fix a bug reported and analyzed by Nagaraj Arankal, where the handling of a spurious non-SACK RTO could cause a connection to fail to clear retrans_stamp, causing a later RTO to very prematurely time out the connection with ETIMEDOUT. Here is the buggy scenario, expanding upon Nagaraj Arankal's excellent report: (*1) Send one data packet on a non-SACK connection (*2) Because no ACK packet is received, the packet is retransmitted and we enter CA_Loss; but this retransmission is spurious. (*3) The ACK for the original data is received. The transmitted packet is acknowledged. The TCP timestamp is before the retrans_stamp, so tcp_may_undo() returns true, and tcp_try_undo_loss() returns true without changing state to Open (because tcp_is_sack() is false), and tcp_process_loss() returns without calling tcp_try_undo_recovery(). Normally after undoing a CA_Loss episode, tcp_fastretrans_alert() would see that the connection has returned to CA_Open and fall through and call tcp_try_to_open(), which would set retrans_stamp to 0. However, for non-SACK connections we hold the connection in CA_Loss, so do not fall through to call tcp_try_to_open() and do not set retrans_stamp to 0. So retrans_stamp is (erroneously) still non-zero. At this point the first "retransmission event" has passed and been recovered from. Any future retransmission is a completely new "event". However, retrans_stamp is erroneously still set. (And we are still in CA_Loss, which is correct.) (*4) After 16 minutes (to correspond with tcp_retries2=15), a new data packet is sent. Note: No data is transmitted between (*3) and (*4) and we disabled keep alives. The socket's timeout SHOULD be calculated from this point in time, but instead it's calculated from the prior "event" 16 minutes ago (step (*2)). (*5) Because no ACK packet is received, the packet is retransmitted. (*6) At the time of the 2nd retransmission, the socket returns ETIMEDOUT, prematurely, because retrans_stamp is (erroneously) too far in the past (set at the time of (*2)). This commit fixes this bug by ensuring that we reuse in tcp_try_undo_loss() the same careful logic for non-SACK connections that we have in tcp_try_undo_recovery(). To avoid duplicating logic, we factor out that logic into a new tcp_is_non_sack_preventing_reopen() helper and call that helper from both undo functions. Fixes: da34ac7626b5 ("tcp: only undo on partial ACKs in CA_Loss") Reported-by: Nagaraj Arankal <nagaraj.p.arankal@hpe.com> Link: https://lore.kernel.org/all/SJ0PR84MB1847BE6C24D274C46A1B9B0EB27A9@SJ0PR84MB1847.NAMPRD84.PROD.OUTLOOK.COM/ Signed-off-by: Neal Cardwell <ncardwell@google.com> Signed-off-by: Yuchung Cheng <ycheng@google.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Link: https://lore.kernel.org/r/20220903121023.866900-1-ncardwell.kernel@gmail.com Signed-off-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-09-15tcp: TX zerocopy should not sense pfmemalloc statusEric Dumazet1-1/+1
[ Upstream commit 3261400639463a853ba2b3be8bd009c2a8089775 ] We got a recent syzbot report [1] showing a possible misuse of pfmemalloc page status in TCP zerocopy paths. Indeed, for pages coming from user space or other layers, using page_is_pfmemalloc() is moot, and possibly could give false positives. There has been attempts to make page_is_pfmemalloc() more robust, but not using it in the first place in this context is probably better, removing cpu cycles. Note to stable teams : You need to backport 84ce071e38a6 ("net: introduce __skb_fill_page_desc_noacc") as a prereq. Race is more probable after commit c07aea3ef4d4 ("mm: add a signature in struct page") because page_is_pfmemalloc() is now using low order bit from page->lru.next, which can change more often than page->index. Low order bit should never be set for lru.next (when used as an anchor in LRU list), so KCSAN report is mostly a false positive. Backporting to older kernel versions seems not necessary. [1] BUG: KCSAN: data-race in lru_add_fn / tcp_build_frag write to 0xffffea0004a1d2c8 of 8 bytes by task 18600 on cpu 0: __list_add include/linux/list.h:73 [inline] list_add include/linux/list.h:88 [inline] lruvec_add_folio include/linux/mm_inline.h:105 [inline] lru_add_fn+0x440/0x520 mm/swap.c:228 folio_batch_move_lru+0x1e1/0x2a0 mm/swap.c:246 folio_batch_add_and_move mm/swap.c:263 [inline] folio_add_lru+0xf1/0x140 mm/swap.c:490 filemap_add_folio+0xf8/0x150 mm/filemap.c:948 __filemap_get_folio+0x510/0x6d0 mm/filemap.c:1981 pagecache_get_page+0x26/0x190 mm/folio-compat.c:104 grab_cache_page_write_begin+0x2a/0x30 mm/folio-compat.c:116 ext4_da_write_begin+0x2dd/0x5f0 fs/ext4/inode.c:2988 generic_perform_write+0x1d4/0x3f0 mm/filemap.c:3738 ext4_buffered_write_iter+0x235/0x3e0 fs/ext4/file.c:270 ext4_file_write_iter+0x2e3/0x1210 call_write_iter include/linux/fs.h:2187 [inline] new_sync_write fs/read_write.c:491 [inline] vfs_write+0x468/0x760 fs/read_write.c:578 ksys_write+0xe8/0x1a0 fs/read_write.c:631 __do_sys_write fs/read_write.c:643 [inline] __se_sys_write fs/read_write.c:640 [inline] __x64_sys_write+0x3e/0x50 fs/read_write.c:640 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x2b/0x70 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd read to 0xffffea0004a1d2c8 of 8 bytes by task 18611 on cpu 1: page_is_pfmemalloc include/linux/mm.h:1740 [inline] __skb_fill_page_desc include/linux/skbuff.h:2422 [inline] skb_fill_page_desc include/linux/skbuff.h:2443 [inline] tcp_build_frag+0x613/0xb20 net/ipv4/tcp.c:1018 do_tcp_sendpages+0x3e8/0xaf0 net/ipv4/tcp.c:1075 tcp_sendpage_locked net/ipv4/tcp.c:1140 [inline] tcp_sendpage+0x89/0xb0 net/ipv4/tcp.c:1150 inet_sendpage+0x7f/0xc0 net/ipv4/af_inet.c:833 kernel_sendpage+0x184/0x300 net/socket.c:3561 sock_sendpage+0x5a/0x70 net/socket.c:1054 pipe_to_sendpage+0x128/0x160 fs/splice.c:361 splice_from_pipe_feed fs/splice.c:415 [inline] __splice_from_pipe+0x222/0x4d0 fs/splice.c:559 splice_from_pipe fs/splice.c:594 [inline] generic_splice_sendpage+0x89/0xc0 fs/splice.c:743 do_splice_from fs/splice.c:764 [inline] direct_splice_actor+0x80/0xa0 fs/splice.c:931 splice_direct_to_actor+0x305/0x620 fs/splice.c:886 do_splice_direct+0xfb/0x180 fs/splice.c:974 do_sendfile+0x3bf/0x910 fs/read_write.c:1249 __do_sys_sendfile64 fs/read_write.c:1317 [inline] __se_sys_sendfile64 fs/read_write.c:1303 [inline] __x64_sys_sendfile64+0x10c/0x150 fs/read_write.c:1303 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x2b/0x70 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd value changed: 0x0000000000000000 -> 0xffffea0004a1d288 Reported by Kernel Concurrency Sanitizer on: CPU: 1 PID: 18611 Comm: syz-executor.4 Not tainted 6.0.0-rc2-syzkaller-00248-ge022620b5d05-dirty #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/22/2022 Fixes: c07aea3ef4d4 ("mm: add a signature in struct page") Reported-by: syzbot <syzkaller@googlegroups.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Shakeel Butt <shakeelb@google.com> Reviewed-by: Shakeel Butt <shakeelb@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-09-15rxrpc: Fix ICMP/ICMP6 error handlingDavid Howells2-0/+3
[ Upstream commit ac56a0b48da86fd1b4389632fb7c4c8a5d86eefa ] Because rxrpc pretends to be a tunnel on top of a UDP/UDP6 socket, allowing it to siphon off UDP packets early in the handling of received UDP packets thereby avoiding the packet going through the UDP receive queue, it doesn't get ICMP packets through the UDP ->sk_error_report() callback. In fact, it doesn't appear that there's any usable option for getting hold of ICMP packets. Fix this by adding a new UDP encap hook to distribute error messages for UDP tunnels. If the hook is set, then the tunnel driver will be able to see ICMP packets. The hook provides the offset into the packet of the UDP header of the original packet that caused the notification. An alternative would be to call the ->error_handler() hook - but that requires that the skbuff be cloned (as ip_icmp_error() or ipv6_cmp_error() do, though isn't really necessary or desirable in rxrpc's case is we want to parse them there and then, not queue them). Changes ======= ver #3) - Fixed an uninitialised variable. ver #2) - Fixed some missing CONFIG_AF_RXRPC_IPV6 conditionals. Fixes: 5271953cad31 ("rxrpc: Use the UDP encap_rcv hook") Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-09-08ip: fix triggering of 'icmp redirect'Nicolas Dichtel1-2/+2
commit eb55dc09b5dd040232d5de32812cc83001a23da6 upstream. __mkroute_input() uses fib_validate_source() to trigger an icmp redirect. My understanding is that fib_validate_source() is used to know if the src address and the gateway address are on the same link. For that, fib_validate_source() returns 1 (same link) or 0 (not the same network). __mkroute_input() is the only user of these positive values, all other callers only look if the returned value is negative. Since the below patch, fib_validate_source() didn't return anymore 1 when both addresses are on the same network, because the route lookup returns RT_SCOPE_LINK instead of RT_SCOPE_HOST. But this is, in fact, right. Let's adapat the test to return 1 again when both addresses are on the same link. CC: stable@vger.kernel.org Fixes: 747c14307214 ("ip: fix dflt addr selection for connected nexthop") Reported-by: kernel test robot <yujie.liu@intel.com> Reported-by: Heng Qi <hengqi@linux.alibaba.com> Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com> Reviewed-by: David Ahern <dsahern@kernel.org> Link: https://lore.kernel.org/r/20220829100121.3821-1-nicolas.dichtel@6wind.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-09-08tcp: annotate data-race around challenge_timestampEric Dumazet1-2/+2
[ Upstream commit 8c70521238b7863c2af607e20bcba20f974c969b ] challenge_timestamp can be read an written by concurrent threads. This was expected, but we need to annotate the race to avoid potential issues. Following patch moves challenge_timestamp and challenge_count to per-netns storage to provide better isolation. Fixes: 354e4aa391ed ("tcp: RFC 5961 5.2 Blind Data Injection Attack Mitigation") Reported-by: syzbot <syzkaller@googlegroups.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Acked-by: Neal Cardwell <ncardwell@google.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-09-08ip_tunnel: Respect tunnel key's "flow_flags" in IP tunnelsEyal Birger2-4/+5
[ Upstream commit 7ec9fce4b31604f8415136a4c07f7dc8ad431aec ] Commit 451ef36bd229 ("ip_tunnels: Add new flow flags field to ip_tunnel_key") added a "flow_flags" member to struct ip_tunnel_key which was later used by the commit in the fixes tag to avoid dropping packets with sources that aren't locally configured when set in bpf_set_tunnel_key(). VXLAN and GENEVE were made to respect this flag, ip tunnels like IPIP and GRE were not. This commit fixes this omission by making ip_tunnel_init_flow() receive the flow flags from the tunnel key in the relevant collect_md paths. Fixes: b8fff748521c ("bpf: Set flow flag to allow any source IP in bpf_tunnel_key") Signed-off-by: Eyal Birger <eyal.birger@gmail.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Reviewed-by: Paul Chaignon <paul@isovalent.com> Link: https://lore.kernel.org/bpf/20220818074118.726639-1-eyal.birger@gmail.com Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-08-31net: Fix data-races around sysctl_devconf_inherit_init_net.Kuniyuki Iwashima1-6/+10
[ Upstream commit a5612ca10d1aa05624ebe72633e0c8c792970833 ] While reading sysctl_devconf_inherit_init_net, it can be changed concurrently. Thus, we need to add READ_ONCE() to its readers. Fixes: 856c395cfa63 ("net: introduce a knob to control whether to inherit devconf config") Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-08-31net: Fix data-races around sysctl_max_skb_frags.Kuniyuki Iwashima1-2/+2
[ Upstream commit 657b991afb89d25fe6c4783b1b75a8ad4563670d ] While reading sysctl_max_skb_frags, it can be changed concurrently. Thus, we need to add READ_ONCE() to its readers. Fixes: 5f74f82ea34c ("net:Add sysctl_max_skb_frags") Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-08-31net: Fix data-races around sysctl_optmem_max.Kuniyuki Iwashima1-3/+3
[ Upstream commit 7de6d09f51917c829af2b835aba8bb5040f8e86a ] While reading sysctl_optmem_max, it can be changed concurrently. Thus, we need to add READ_ONCE() to its readers. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-08-31net: Fix data-races around sysctl_[rw]mem_(max|default).Kuniyuki Iwashima2-2/+2
[ Upstream commit 1227c1771dd2ad44318aa3ab9e3a293b3f34ff2a ] While reading sysctl_[rw]mem_(max|default), they can be changed concurrently. Thus, we need to add READ_ONCE() to its readers. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-08-17raw: fix a typo in raw_icmp_error()Eric Dumazet1-1/+1
commit 97a4d46b1516250d640c1ae0c9e7129d160d6a1c upstream. I accidentally broke IPv4 traceroute, by swapping iph->saddr and iph->daddr. Probably because raw_icmp_error() and raw_v4_input() use different order for iph->saddr and iph->daddr. Fixes: ba44f8182ec2 ("raw: use more conventional iterators") Reported-by: John Sperbeck <jsperbeck@google.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Link: https://lore.kernel.org/r/20220623193540.2851799-1-edumazet@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-08-17tcp: fix over estimation in sk_forced_mem_schedule()Eric Dumazet1-3/+4
commit c4ee118561a0f74442439b7b5b486db1ac1ddfeb upstream. sk_forced_mem_schedule() has a bug similar to ones fixed in commit 7c80b038d23e ("net: fix sk_wmem_schedule() and sk_rmem_schedule() errors") While this bug has little chance to trigger in old kernels, we need to fix it before the following patch. Fixes: d83769a580f1 ("tcp: fix possible deadlock in tcp_send_fin()") Signed-off-by: Eric Dumazet <edumazet@google.com> Acked-by: Soheil Hassas Yeganeh <soheil@google.com> Reviewed-by: Shakeel Butt <shakeelb@google.com> Reviewed-by: Wei Wang <weiwan@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-08-17tcp: make retransmitted SKB fit into the send windowYonglong Li1-7/+16
[ Upstream commit 536a6c8e05f95e3d1118c40ae8b3022ee2d05d52 ] current code of __tcp_retransmit_skb only check TCP_SKB_CB(skb)->seq in send window, and TCP_SKB_CB(skb)->seq_end maybe out of send window. If receiver has shrunk his window, and skb is out of new window, it should retransmit a smaller portion of the payload. test packetdrill script: 0 socket(..., SOCK_STREAM, IPPROTO_TCP) = 3 +0 fcntl(3, F_GETFL) = 0x2 (flags O_RDWR) +0 fcntl(3, F_SETFL, O_RDWR|O_NONBLOCK) = 0 +0 connect(3, ..., ...) = -1 EINPROGRESS (Operation now in progress) +0 > S 0:0(0) win 65535 <mss 1460,sackOK,TS val 100 ecr 0,nop,wscale 8> +.05 < S. 0:0(0) ack 1 win 6000 <mss 1000,nop,nop,sackOK> +0 > . 1:1(0) ack 1 +0 write(3, ..., 10000) = 10000 +0 > . 1:2001(2000) ack 1 win 65535 +0 > . 2001:4001(2000) ack 1 win 65535 +0 > . 4001:6001(2000) ack 1 win 65535 +.05 < . 1:1(0) ack 4001 win 1001 and tcpdump show: 192.168.226.67.55 > 192.0.2.1.8080: Flags [.], seq 1:2001, ack 1, win 65535, length 2000 192.168.226.67.55 > 192.0.2.1.8080: Flags [.], seq 2001:4001, ack 1, win 65535, length 2000 192.168.226.67.55 > 192.0.2.1.8080: Flags [P.], seq 4001:5001, ack 1, win 65535, length 1000 192.168.226.67.55 > 192.0.2.1.8080: Flags [.], seq 5001:6001, ack 1, win 65535, length 1000 192.0.2.1.8080 > 192.168.226.67.55: Flags [.], ack 4001, win 1001, length 0 192.168.226.67.55 > 192.0.2.1.8080: Flags [.], seq 5001:6001, ack 1, win 65535, length 1000 192.168.226.67.55 > 192.0.2.1.8080: Flags [P.], seq 4001:5001, ack 1, win 65535, length 1000 when cient retract window to 1001, send window is [4001,5002], but TLP send 5001-6001 packet which is out of send window. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Yonglong Li <liyonglong@chinatelecom.cn> Signed-off-by: Eric Dumazet <edumazet@google.com> Link: https://lore.kernel.org/r/1657532838-20200-1-git-send-email-liyonglong@chinatelecom.cn Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-08-17raw: Fix mixed declarations error in raw_icmp_error().Kuniyuki Iwashima1-1/+1
[ Upstream commit 5da39e31b1b0eb62b8ed369ad9615da850239e9e ] The trailing semicolon causes a compiler error, so let's remove it. net/ipv4/raw.c: In function ‘raw_icmp_error’: net/ipv4/raw.c:266:2: error: ISO C90 forbids mixed declarations and code [-Werror=declaration-after-statement] 266 | struct hlist_nulls_head *hlist; | ^~~~~~ Fixes: ba44f8182ec2 ("raw: use more conventional iterators") Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-08-17raw: convert raw sockets to RCUEric Dumazet3-54/+53
[ Upstream commit 0daf07e527095e64ee8927ce297ab626643e9f51 ] Using rwlock in networking code is extremely risky. writers can starve if enough readers are constantly grabing the rwlock. I thought rwlock were at fault and sent this patch: https://lkml.org/lkml/2022/6/17/272 But Peter and Linus essentially told me rwlock had to be unfair. We need to get rid of rwlock in networking code. Without this fix, following script triggers soft lockups: for i in {1..48} do ping -f -n -q 127.0.0.1 & sleep 0.1 done Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-08-17raw: use more conventional iteratorsEric Dumazet2-77/+49
[ Upstream commit ba44f8182ec299c5d1c8a72fc0fde4ec127b5a6d ] In order to prepare the following patch, I change raw v4 & v6 code to use more conventional iterators. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-08-17ping: convert to RCU lookups, get rid of rwlockEric Dumazet1-20/+16
[ Upstream commit dbca1596bbb08318f5e3b3b99f8ca0a0d3830a65 ] Using rwlock in networking code is extremely risky. writers can starve if enough readers are constantly grabing the rwlock. I thought rwlock were at fault and sent this patch: https://lkml.org/lkml/2022/6/17/272 But Peter and Linus essentially told me rwlock had to be unfair. We need to get rid of rwlock in networking code. Fixes: c319b4d76b9e ("net: ipv4: add IPPROTO_ICMP socket kind") Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-08-17tcp: fix possible freeze in tx path under memory pressureEric Dumazet1-4/+29
[ Upstream commit 849b425cd091e1804af964b771761cfbefbafb43 ] Blamed commit only dealt with applications issuing small writes. Issue here is that we allow to force memory schedule for the sk_buff allocation, but we have no guarantee that sendmsg() is able to copy some payload in it. In this patch, I make sure the socket can use up to tcp_wmem[0] bytes. For example, if we consider tcp_wmem[0] = 4096 (default on x86), and initial skb->truesize being 1280, tcp_sendmsg() is able to copy up to 2816 bytes under memory pressure. Before this patch a sendmsg() sending more than 2816 bytes would either block forever (if persistent memory pressure), or return -EAGAIN. For bigger MTU networks, it is advised to increase tcp_wmem[0] to avoid sending too small packets. v2: deal with zero copy paths. Fixes: 8e4d980ac215 ("tcp: fix behavior for epoll edge trigger") Signed-off-by: Eric Dumazet <edumazet@google.com> Acked-by: Soheil Hassas Yeganeh <soheil@google.com> Reviewed-by: Wei Wang <weiwan@google.com> Reviewed-by: Shakeel Butt <shakeelb@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-07-27tcp: md5: fix IPv4-mapped supportEric Dumazet1-3/+12
After the blamed commit, IPv4 SYN packets handled by a dual stack IPv6 socket are dropped, even if perfectly valid. $ nstat | grep MD5 TcpExtTCPMD5Failure 5 0.0 For a dual stack listener, an incoming IPv4 SYN packet would call tcp_inbound_md5_hash() with @family == AF_INET, while tp->af_specific is pointing to tcp_sock_ipv6_specific. Only later when an IPv4-mapped child is created, tp->af_specific is changed to tcp_sock_ipv6_mapped_specific. Fixes: 7bbb765b7349 ("net/tcp: Merge TCP-MD5 inbound callbacks") Reported-by: Brian Vazquez <brianvv@google.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: David Ahern <dsahern@kernel.org> Reviewed-by: Dmitry Safonov <dima@arista.com> Tested-by: Leonard Crestez <cdleonard@gmail.com> Link: https://lore.kernel.org/r/20220726115743.2759832-1-edumazet@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-07-25ipv4: Fix data-races around sysctl_fib_notify_on_flag_change.Kuniyuki Iwashima1-2/+5
While reading sysctl_fib_notify_on_flag_change, it can be changed concurrently. Thus, we need to add READ_ONCE() to its readers. Fixes: 680aea08e78c ("net: ipv4: Emit notification when fib hardware flags are changed") Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2022-07-25tcp: Fix data-races around sysctl_tcp_reflect_tos.Kuniyuki Iwashima1-2/+2
While reading sysctl_tcp_reflect_tos, it can be changed concurrently. Thus, we need to add READ_ONCE() to its readers. Fixes: ac8f1710c12b ("tcp: reflect tos value received in SYN to the socket") Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Acked-by: Wei Wang <weiwan@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2022-07-25tcp: Fix a data-race around sysctl_tcp_comp_sack_nr.Kuniyuki Iwashima1-1/+1
While reading sysctl_tcp_comp_sack_nr, it can be changed concurrently. Thus, we need to add READ_ONCE() to its reader. Fixes: 9c21d2fc41c0 ("tcp: add tcp_comp_sack_nr sysctl") Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2022-07-25tcp: Fix a data-race around sysctl_tcp_comp_sack_slack_ns.Kuniyuki Iwashima1-1/+1
While reading sysctl_tcp_comp_sack_slack_ns, it can be changed concurrently. Thus, we need to add READ_ONCE() to its reader. Fixes: a70437cc09a1 ("tcp: add hrtimer slack to sack compression") Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2022-07-25tcp: Fix a data-race around sysctl_tcp_comp_sack_delay_ns.Kuniyuki Iwashima1-1/+2
While reading sysctl_tcp_comp_sack_delay_ns, it can be changed concurrently. Thus, we need to add READ_ONCE() to its reader. Fixes: 6d82aa242092 ("tcp: add tcp_comp_sack_delay_ns sysctl") Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2022-07-25net: Fix data-races around sysctl_[rw]mem(_offset)?.Kuniyuki Iwashima3-10/+11
While reading these sysctl variables, they can be changed concurrently. Thus, we need to add READ_ONCE() to their readers. - .sysctl_rmem - .sysctl_rwmem - .sysctl_rmem_offset - .sysctl_wmem_offset - sysctl_tcp_rmem[1, 2] - sysctl_tcp_wmem[1, 2] - sysctl_decnet_rmem[1] - sysctl_decnet_wmem[1] - sysctl_tipc_rmem[1] Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2022-07-25tcp: Fix data-races around sk_pacing_rate.Kuniyuki Iwashima1-2/+2
While reading sysctl_tcp_pacing_(ss|ca)_ratio, they can be changed concurrently. Thus, we need to add READ_ONCE() to their readers. Fixes: 43e122b014c9 ("tcp: refine pacing rate determination") Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2022-07-23Revert "tcp: change pingpong threshold to 3"Wei Wang1-9/+6
This reverts commit 4a41f453bedfd5e9cd040bad509d9da49feb3e2c. This to-be-reverted commit was meant to apply a stricter rule for the stack to enter pingpong mode. However, the condition used to check for interactive session "before(tp->lsndtime, icsk->icsk_ack.lrcvtime)" is jiffy based and might be too coarse, which delays the stack entering pingpong mode. We revert this patch so that we no longer use the above condition to determine interactive session, and also reduce pingpong threshold to 1. Fixes: 4a41f453bedf ("tcp: change pingpong threshold to 3") Reported-by: LemmyHuang <hlm3280@163.com> Suggested-by: Neal Cardwell <ncardwell@google.com> Signed-off-by: Wei Wang <weiwan@google.com> Acked-by: Neal Cardwell <ncardwell@google.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Link: https://lore.kernel.org/r/20220721204404.388396-1-weiwan@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-07-22tcp: Fix a data-race around sysctl_tcp_invalid_ratelimit.Kuniyuki Iwashima1-1/+2
While reading sysctl_tcp_invalid_ratelimit, it can be changed concurrently. Thus, we need to add READ_ONCE() to its reader. Fixes: 032ee4236954 ("tcp: helpers to mitigate ACK loops by rate-limiting out-of-window dupacks") Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2022-07-22tcp: Fix a data-race around sysctl_tcp_autocorking.Kuniyuki Iwashima1-1/+1
While reading sysctl_tcp_autocorking, it can be changed concurrently. Thus, we need to add READ_ONCE() to its reader. Fixes: f54b311142a9 ("tcp: auto corking") Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2022-07-22tcp: Fix a data-race around sysctl_tcp_min_rtt_wlen.Kuniyuki Iwashima1-1/+1
While reading sysctl_tcp_min_rtt_wlen, it can be changed concurrently. Thus, we need to add READ_ONCE() to its reader. Fixes: f672258391b4 ("tcp: track min RTT using windowed min-filter") Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2022-07-22tcp: Fix a data-race around sysctl_tcp_tso_rtt_log.Kuniyuki Iwashima1-1/+1
While reading sysctl_tcp_tso_rtt_log, it can be changed concurrently. Thus, we need to add READ_ONCE() to its reader. Fixes: 65466904b015 ("tcp: adjust TSO packet sizes based on min_rtt") Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2022-07-22tcp: Fix a data-race around sysctl_tcp_min_tso_segs.Kuniyuki Iwashima1-1/+1
While reading sysctl_tcp_min_tso_segs, it can be changed concurrently. Thus, we need to add READ_ONCE() to its reader. Fixes: 95bd09eb2750 ("tcp: TSO packets automatic sizing") Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2022-07-22tcp: Fix a data-race around sysctl_tcp_challenge_ack_limit.Kuniyuki Iwashima1-1/+1
While reading sysctl_tcp_challenge_ack_limit, it can be changed concurrently. Thus, we need to add READ_ONCE() to its reader. Fixes: 282f23c6ee34 ("tcp: implement RFC 5961 3.2") Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2022-07-22tcp: Fix a data-race around sysctl_tcp_limit_output_bytes.Kuniyuki Iwashima1-1/+1
While reading sysctl_tcp_limit_output_bytes, it can be changed concurrently. Thus, we need to add READ_ONCE() to its reader. Fixes: 46d3ceabd8d9 ("tcp: TCP Small Queues") Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2022-07-22tcp: Fix data-races around sysctl_tcp_workaround_signed_windows.Kuniyuki Iwashima1-2/+2
While reading sysctl_tcp_workaround_signed_windows, it can be changed concurrently. Thus, we need to add READ_ONCE() to its readers. Fixes: 15d99e02baba ("[TCP]: sysctl to allow TCP window > 32767 sans wscale") Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2022-07-22tcp: Fix data-races around sysctl_tcp_moderate_rcvbuf.Kuniyuki Iwashima1-1/+1
While reading sysctl_tcp_moderate_rcvbuf, it can be changed concurrently. Thus, we need to add READ_ONCE() to its readers. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2022-07-22tcp: Fix data-races around sysctl_tcp_no_ssthresh_metrics_save.Kuniyuki Iwashima1-4/+4
While reading sysctl_tcp_no_ssthresh_metrics_save, it can be changed concurrently. Thus, we need to add READ_ONCE() to its readers. Fixes: 65e6d90168f3 ("net-tcp: Disable TCP ssthresh metrics cache by default") Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2022-07-22tcp: Fix a data-race around sysctl_tcp_nometrics_save.Kuniyuki Iwashima1-1/+1
While reading sysctl_tcp_nometrics_save, it can be changed concurrently. Thus, we need to add READ_ONCE() to its reader. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2022-07-22tcp: Fix a data-race around sysctl_tcp_frto.Kuniyuki Iwashima1-1/+1
While reading sysctl_tcp_frto, it can be changed concurrently. Thus, we need to add READ_ONCE() to its reader. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2022-07-22tcp: Fix a data-race around sysctl_tcp_app_win.Kuniyuki Iwashima1-1/+1
While reading sysctl_tcp_app_win, it can be changed concurrently. Thus, we need to add READ_ONCE() to its reader. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2022-07-22tcp: Fix data-races around sysctl_tcp_dsack.Kuniyuki Iwashima1-2/+2
While reading sysctl_tcp_dsack, it can be changed concurrently. Thus, we need to add READ_ONCE() to its readers. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2022-07-20tcp: Fix data-races around sysctl_tcp_max_reordering.Kuniyuki Iwashima1-2/+2
While reading sysctl_tcp_max_reordering, it can be changed concurrently. Thus, we need to add READ_ONCE() to its readers. Fixes: dca145ffaa8d ("tcp: allow for bigger reordering level") Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2022-07-20tcp: Fix a data-race around sysctl_tcp_abort_on_overflow.Kuniyuki Iwashima1-1/+1
While reading sysctl_tcp_abort_on_overflow, it can be changed concurrently. Thus, we need to add READ_ONCE() to its reader. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Signed-off-by: David S. Miller <davem@davemloft.net>