linux/net/ipv4, branch v5.15

net: Implement ->sock_is_readable() for UDP and AF_UNIX

2021-10-26T19:29:33Z

Yucong noticed we can't poll() sockets in sockmap even when they are the destination sockets of redirections. This is because we never poll any psock queues in ->poll(), except for TCP. With ->sock_is_readable() now we can overwrite >sock_is_readable(), invoke and implement it for both UDP and AF_UNIX sockets. Reported-by: Yucong Sun Signed-off-by: Cong Wang Signed-off-by: Alexei Starovoitov Link: https://lore.kernel.org/bpf/20211008203306.37525-4-xiyou.wangcong@gmail.com

skmsg: Extract and reuse sk_msg_is_readable()

2021-10-26T19:29:33Z

tcp_bpf_sock_is_readable() is pretty much generic, we can extract it and reuse it for non-TCP sockets. Signed-off-by: Cong Wang Signed-off-by: Alexei Starovoitov Link: https://lore.kernel.org/bpf/20211008203306.37525-3-xiyou.wangcong@gmail.com

net: Rename ->stream_memory_read to ->sock_is_readable

2021-10-26T19:29:33Z

The proto ops ->stream_memory_read() is currently only used by TCP to check whether psock queue is empty or not. We need to rename it before reusing it for non-TCP protocols, and adjust the exsiting users accordingly. Signed-off-by: Cong Wang Signed-off-by: Alexei Starovoitov Link: https://lore.kernel.org/bpf/20211008203306.37525-2-xiyou.wangcong@gmail.com

tcp_bpf: Fix one concurrency problem in the tcp_bpf_send_verdict function

2021-10-26T19:25:55Z

With two Msgs, msgA and msgB and a user doing nonblocking sendmsg calls (or multiple cores) on a single socket 'sk' we could get the following flow. msgA, sk msgB, sk ----------- --------------- tcp_bpf_sendmsg() lock(sk) psock = sk->psock tcp_bpf_sendmsg() lock(sk) ... blocking tcp_bpf_send_verdict if (psock->eval == NONE) psock->eval = sk_psock_msg_verdict .. < handle SK_REDIRECT case > release_sock(sk) < lock dropped so grab here > ret = tcp_bpf_sendmsg_redir psock = sk->psock tcp_bpf_send_verdict lock_sock(sk) ... blocking on B if (psock->eval == NONE) <- boom. psock->eval will have msgA state The problem here is we dropped the lock on msgA and grabbed it with msgB. Now we have old state in psock and importantly psock->eval has not been cleared. So msgB will run whatever action was done on A and the verdict program may never see it. Fixes: 604326b41a6fb ("bpf, sockmap: convert to generic sk_msg interface") Signed-off-by: Liu Jian Signed-off-by: Alexei Starovoitov Acked-by: John Fastabend Link: https://lore.kernel.org/bpf/20211012052019.184398-1-liujian56@huawei.com

tcp: md5: Allow MD5SIG_FLAG_IFINDEX with ifindex=0

2021-10-15T13:36:57Z

Multiple VRFs are generally meant to be "separate" but right now md5 keys for the default VRF also affect connections inside VRFs if the IP addresses happen to overlap. So far the combination of TCP_MD5SIG_FLAG_IFINDEX with tcpm_ifindex == 0 was an error, accept this to mean "key only applies to default VRF". This is what applications using VRFs for traffic separation want. Signed-off-by: Leonard Crestez Reviewed-by: David Ahern Signed-off-by: David S. Miller

tcp: md5: Fix overlap between vrf and non-vrf keys

2021-10-15T13:36:57Z

With net.ipv4.tcp_l3mdev_accept=1 it is possible for a listen socket to accept connection from the same client address in different VRFs. It is also possible to set different MD5 keys for these clients which differ only in the tcpm_l3index field. This appears to work when distinguishing between different VRFs but not between non-VRF and VRF connections. In particular: * tcp_md5_do_lookup_exact will match a non-vrf key against a vrf key. This means that adding a key with l3index != 0 after a key with l3index == 0 will cause the earlier key to be deleted. Both keys can be present if the non-vrf key is added later. * _tcp_md5_do_lookup can match a non-vrf key before a vrf key. This casues failures if the passwords differ. Fix this by making tcp_md5_do_lookup_exact perform an actual exact comparison on l3index and by making __tcp_md5_do_lookup perfer vrf-bound keys above other considerations like prefixlen. Fixes: dea53bb80e07 ("tcp: Add l3index to tcp_md5sig_key and md5 functions") Signed-off-by: Leonard Crestez Reviewed-by: David Ahern Signed-off-by: David S. Miller

icmp: fix icmp_ext_echo_iio parsing in icmp_build_probe

2021-10-14T14:54:47Z

In icmp_build_probe(), the icmp_ext_echo_iio parsing should be done step by step and skb_header_pointer() return value should always be checked, this patch fixes 3 places in there: - On case ICMP_EXT_ECHO_CTYPE_NAME, it should only copy ident.name from skb by skb_header_pointer(), its len is ident_len. Besides, the return value of skb_header_pointer() should always be checked. - On case ICMP_EXT_ECHO_CTYPE_INDEX, move ident_len check ahead of skb_header_pointer(), and also do the return value check for skb_header_pointer(). - On case ICMP_EXT_ECHO_CTYPE_ADDR, before accessing iio->ident.addr. ctype3_hdr.addrlen, skb_header_pointer() should be called first, then check its return value and ident_len. On subcases ICMP_AFI_IP and ICMP_AFI_IP6, also do check for ident. addr.ctype3_hdr.addrlen and skb_header_pointer()'s return value. On subcase ICMP_AFI_IP, the len for skb_header_pointer() should be "sizeof(iio->extobj_hdr) + sizeof(iio->ident.addr.ctype3_hdr) + sizeof(struct in_addr)" or "ident_len". v1->v2: - To make it more clear, call skb_header_pointer() once only for iio->indent's parsing as Jakub Suggested. v2->v3: - The extobj_hdr.length check against sizeof(_iio) should be done before calling skb_header_pointer(), as Eric noticed. Fixes: d329ea5bd884 ("icmp: add response to RFC 8335 PROBE messages") Reported-by: Dan Carpenter Signed-off-by: Xin Long Reviewed-by: Eric Dumazet Link: https://lore.kernel.org/r/31628dd76657ea62f5cf78bb55da6b35240831f1.1634205050.git.lucien.xin@gmail.com Signed-off-by: Jakub Kicinski

net: prefer socket bound to interface when not in VRF

2021-10-07T14:27:55Z

The commit 6da5b0f027a8 ("net: ensure unbound datagram socket to be chosen when not in a VRF") modified compute_score() so that a device match is always made, not just in the case of an l3mdev skb, then increments the score also for unbound sockets. This ensures that sockets bound to an l3mdev are never selected when not in a VRF. But as unbound and bound sockets are now scored equally, this results in the last opened socket being selected if there are matches in the default VRF for an unbound socket and a socket bound to a dev that is not an l3mdev. However, handling prior to this commit was to always select the bound socket in this case. Reinstate this handling by incrementing the score only for bound sockets. The required isolation due to choosing between an unbound socket and a socket bound to an l3mdev remains in place due to the device match always being made. The same approach is taken for compute_score() for stream sockets. Fixes: 6da5b0f027a8 ("net: ensure unbound datagram socket to be chosen when not in a VRF") Fixes: e78190581aff ("net: ensure unbound stream socket to be chosen when not in a VRF") Signed-off-by: Mike Manning Reviewed-by: David Ahern Link: https://lore.kernel.org/r/cf0a8523-b362-1edf-ee78-eef63cbbb428@gmail.com Signed-off-by: Jakub Kicinski

Merge git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf

2021-10-02T12:55:02Z

Pablo Neira Ayuso says: ==================== Netfilter fixes for net (v2) The following patchset contains Netfilter fixes for net: 1) Move back the defrag users fields to the global netns_nf area. Kernel fails to boot if conntrack is builtin and kernel is booted with: nf_conntrack.enable_hooks=1. From Florian Westphal. 2) Rule event notification is missing relevant context such as the position handle and the NLM_F_APPEND flag. 3) Rule replacement is expanded to add + delete using the existing rule handle, reverse order of this operation so it makes sense from rule notification standpoint. 4) Propagate to userspace the NLM_F_CREATE and NLM_F_EXCL flags from the rule notification path. Patches #2, #3 and #4 are used by 'nft monitor' and 'iptables-monitor' userspace utilities which are not correctly representing the following operations through netlink notifications: - rule insertions - rule addition/insertion from position handle - create table/chain/set/map/flowtable/... ==================== Signed-off-by: David S. Miller

net: udp: annotate data race around udp_sk(sk)->corkflag

2021-09-28T12:21:16Z

up->corkflag field can be read or written without any lock. Annotate accesses to avoid possible syzbot/KCSAN reports. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Eric Dumazet Signed-off-by: David S. Miller