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2023-05-26Merge tag 'for-netdev' of ↵Jakub Kicinski
https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next Daniel Borkmann says: ==================== pull-request: bpf-next 2023-05-26 We've added 54 non-merge commits during the last 10 day(s) which contain a total of 76 files changed, 2729 insertions(+), 1003 deletions(-). The main changes are: 1) Add the capability to destroy sockets in BPF through a new kfunc, from Aditi Ghag. 2) Support O_PATH fds in BPF_OBJ_PIN and BPF_OBJ_GET commands, from Andrii Nakryiko. 3) Add capability for libbpf to resize datasec maps when backed via mmap, from JP Kobryn. 4) Move all the test kfuncs for CI out of the kernel and into bpf_testmod, from Jiri Olsa. 5) Big batch of xsk selftest improvements to prep for multi-buffer testing, from Magnus Karlsson. 6) Show the target_{obj,btf}_id in tracing link's fdinfo and dump it via bpftool, from Yafang Shao. 7) Various misc BPF selftest improvements to work with upcoming LLVM 17, from Yonghong Song. 8) Extend bpftool to specify netdevice for resolving XDP hints, from Larysa Zaremba. 9) Document masking in shift operations for the insn set document, from Dave Thaler. 10) Extend BPF selftests to check xdp_feature support for bond driver, from Lorenzo Bianconi. * tag 'for-netdev' of https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (54 commits) bpf: Fix bad unlock balance on freeze_mutex libbpf: Ensure FD >= 3 during bpf_map__reuse_fd() libbpf: Ensure libbpf always opens files with O_CLOEXEC selftests/bpf: Check whether to run selftest libbpf: Change var type in datasec resize func bpf: drop unnecessary bpf_capable() check in BPF_MAP_FREEZE command libbpf: Selftests for resizing datasec maps libbpf: Add capability for resizing datasec maps selftests/bpf: Add path_fd-based BPF_OBJ_PIN and BPF_OBJ_GET tests libbpf: Add opts-based bpf_obj_pin() API and add support for path_fd bpf: Support O_PATH FDs in BPF_OBJ_PIN and BPF_OBJ_GET commands libbpf: Start v1.3 development cycle bpf: Validate BPF object in BPF_OBJ_PIN before calling LSM bpftool: Specify XDP Hints ifname when loading program selftests/bpf: Add xdp_feature selftest for bond device selftests/bpf: Test bpf_sock_destroy selftests/bpf: Add helper to get port using getsockname bpf: Add bpf_sock_destroy kfunc bpf: Add kfunc filter function to 'struct btf_kfunc_id_set' bpf: udp: Implement batching for sockets iterator ... ==================== Link: https://lore.kernel.org/r/20230526222747.17775-1-daniel@iogearbox.net Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-05-26net: ynl: prefix uAPI header include with uapi/Jakub Kicinski
To keep things simple we used to include the uAPI header in the kernel in the #include <linux/$family.h> format. This works well enough, most of the genl families should have headers in include/net/ so linux/$family.h ends up referring to the uAPI header, anyway. And if it doesn't no big deal, we'll just include more info than we need. Unless that is there is a naming conflict. Someone recently created include/linux/psp.h which will be a problem when supporting the PSP protocol. (I'm talking about work-in-progress patches, but it's just a proof that assuming lack of name conflicts was overly optimistic.) Signed-off-by: Jakub Kicinski <kuba@kernel.org> Reviewed-by: Simon Horman <simon.horman@corigine.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>
2023-05-25net: tcp: make the txhash available in TIME_WAIT sockets for IPv4 tooAntoine Tenart
Commit c67b85558ff2 ("ipv6: tcp: send consistent autoflowlabel in TIME_WAIT state") made the socket txhash also available in TIME_WAIT sockets but for IPv6 only. Make it available for IPv4 too as we'll use it in later commits. Signed-off-by: Antoine Tenart <atenart@kernel.org> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2023-05-25udplite: Fix NULL pointer dereference in __sk_mem_raise_allocated().Kuniyuki Iwashima
syzbot reported [0] a null-ptr-deref in sk_get_rmem0() while using IPPROTO_UDPLITE (0x88): 14:25:52 executing program 1: r0 = socket$inet6(0xa, 0x80002, 0x88) We had a similar report [1] for probably sk_memory_allocated_add() in __sk_mem_raise_allocated(), and commit c915fe13cbaa ("udplite: fix NULL pointer dereference") fixed it by setting .memory_allocated for udplite_prot and udplitev6_prot. To fix the variant, we need to set either .sysctl_wmem_offset or .sysctl_rmem. Now UDP and UDPLITE share the same value for .memory_allocated, so we use the same .sysctl_wmem_offset for UDP and UDPLITE. [0]: general protection fault, probably for non-canonical address 0xdffffc0000000000: 0000 [#1] PREEMPT SMP KASAN KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007] CPU: 0 PID: 6829 Comm: syz-executor.1 Not tainted 6.4.0-rc2-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/28/2023 RIP: 0010:sk_get_rmem0 include/net/sock.h:2907 [inline] RIP: 0010:__sk_mem_raise_allocated+0x806/0x17a0 net/core/sock.c:3006 Code: c1 ea 03 80 3c 02 00 0f 85 23 0f 00 00 48 8b 44 24 08 48 8b 98 38 01 00 00 48 b8 00 00 00 00 00 fc ff df 48 89 da 48 c1 ea 03 <0f> b6 14 02 48 89 d8 83 e0 07 83 c0 03 38 d0 0f 8d 6f 0a 00 00 8b RSP: 0018:ffffc90005d7f450 EFLAGS: 00010246 RAX: dffffc0000000000 RBX: 0000000000000000 RCX: ffffc90004d92000 RDX: 0000000000000000 RSI: ffffffff88066482 RDI: ffffffff8e2ccbb8 RBP: ffff8880173f7000 R08: 0000000000000005 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000030000 R13: 0000000000000001 R14: 0000000000000340 R15: 0000000000000001 FS: 0000000000000000(0000) GS:ffff8880b9800000(0063) knlGS:00000000f7f1cb40 CS: 0010 DS: 002b ES: 002b CR0: 0000000080050033 CR2: 000000002e82f000 CR3: 0000000034ff0000 CR4: 00000000003506f0 Call Trace: <TASK> __sk_mem_schedule+0x6c/0xe0 net/core/sock.c:3077 udp_rmem_schedule net/ipv4/udp.c:1539 [inline] __udp_enqueue_schedule_skb+0x776/0xb30 net/ipv4/udp.c:1581 __udpv6_queue_rcv_skb net/ipv6/udp.c:666 [inline] udpv6_queue_rcv_one_skb+0xc39/0x16c0 net/ipv6/udp.c:775 udpv6_queue_rcv_skb+0x194/0xa10 net/ipv6/udp.c:793 __udp6_lib_mcast_deliver net/ipv6/udp.c:906 [inline] __udp6_lib_rcv+0x1bda/0x2bd0 net/ipv6/udp.c:1013 ip6_protocol_deliver_rcu+0x2e7/0x1250 net/ipv6/ip6_input.c:437 ip6_input_finish+0x150/0x2f0 net/ipv6/ip6_input.c:482 NF_HOOK include/linux/netfilter.h:303 [inline] NF_HOOK include/linux/netfilter.h:297 [inline] ip6_input+0xa0/0xd0 net/ipv6/ip6_input.c:491 ip6_mc_input+0x40b/0xf50 net/ipv6/ip6_input.c:585 dst_input include/net/dst.h:468 [inline] ip6_rcv_finish net/ipv6/ip6_input.c:79 [inline] NF_HOOK include/linux/netfilter.h:303 [inline] NF_HOOK include/linux/netfilter.h:297 [inline] ipv6_rcv+0x250/0x380 net/ipv6/ip6_input.c:309 __netif_receive_skb_one_core+0x114/0x180 net/core/dev.c:5491 __netif_receive_skb+0x1f/0x1c0 net/core/dev.c:5605 netif_receive_skb_internal net/core/dev.c:5691 [inline] netif_receive_skb+0x133/0x7a0 net/core/dev.c:5750 tun_rx_batched+0x4b3/0x7a0 drivers/net/tun.c:1553 tun_get_user+0x2452/0x39c0 drivers/net/tun.c:1989 tun_chr_write_iter+0xdf/0x200 drivers/net/tun.c:2035 call_write_iter include/linux/fs.h:1868 [inline] new_sync_write fs/read_write.c:491 [inline] vfs_write+0x945/0xd50 fs/read_write.c:584 ksys_write+0x12b/0x250 fs/read_write.c:637 do_syscall_32_irqs_on arch/x86/entry/common.c:112 [inline] __do_fast_syscall_32+0x65/0xf0 arch/x86/entry/common.c:178 do_fast_syscall_32+0x33/0x70 arch/x86/entry/common.c:203 entry_SYSENTER_compat_after_hwframe+0x70/0x82 RIP: 0023:0xf7f21579 Code: b8 01 10 06 03 74 b4 01 10 07 03 74 b0 01 10 08 03 74 d8 01 00 00 00 00 00 00 00 00 00 00 00 00 00 51 52 55 89 e5 0f 34 cd 80 <5d> 5a 59 c3 90 90 90 90 8d b4 26 00 00 00 00 8d b4 26 00 00 00 00 RSP: 002b:00000000f7f1c590 EFLAGS: 00000282 ORIG_RAX: 0000000000000004 RAX: ffffffffffffffda RBX: 00000000000000c8 RCX: 0000000020000040 RDX: 0000000000000083 RSI: 00000000f734e000 RDI: 0000000000000000 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000296 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 </TASK> Modules linked in: Link: https://lore.kernel.org/netdev/CANaxB-yCk8hhP68L4Q2nFOJht8sqgXGGQO2AftpHs0u1xyGG5A@mail.gmail.com/ [1] Fixes: 850cbaddb52d ("udp: use it's own memory accounting schema") Reported-by: syzbot+444ca0907e96f7c5e48b@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=444ca0907e96f7c5e48b Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Link: https://lore.kernel.org/r/20230523163305.66466-1-kuniyu@amazon.com Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2023-05-24Merge tag 'for-netdev' of ↵Jakub Kicinski
https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf Daniel Borkmann says: ==================== pull-request: bpf 2023-05-24 We've added 19 non-merge commits during the last 10 day(s) which contain a total of 20 files changed, 738 insertions(+), 448 deletions(-). The main changes are: 1) Batch of BPF sockmap fixes found when running against NGINX TCP tests, from John Fastabend. 2) Fix a memleak in the LRU{,_PERCPU} hash map when bucket locking fails, from Anton Protopopov. 3) Init the BPF offload table earlier than just late_initcall, from Jakub Kicinski. 4) Fix ctx access mask generation for 32-bit narrow loads of 64-bit fields, from Will Deacon. 5) Remove a now unsupported __fallthrough in BPF samples, from Andrii Nakryiko. 6) Fix a typo in pkg-config call for building sign-file, from Jeremy Sowden. * tag 'for-netdev' of https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf: bpf, sockmap: Test progs verifier error with latest clang bpf, sockmap: Test FIONREAD returns correct bytes in rx buffer with drops bpf, sockmap: Test FIONREAD returns correct bytes in rx buffer bpf, sockmap: Test shutdown() correctly exits epoll and recv()=0 bpf, sockmap: Build helper to create connected socket pair bpf, sockmap: Pull socket helpers out of listen test for general use bpf, sockmap: Incorrectly handling copied_seq bpf, sockmap: Wake up polling after data copy bpf, sockmap: TCP data stall on recv before accept bpf, sockmap: Handle fin correctly bpf, sockmap: Improved check for empty queue bpf, sockmap: Reschedule is now done through backlog bpf, sockmap: Convert schedule_work into delayed_work bpf, sockmap: Pass skb ownership through read_skb bpf: fix a memory leak in the LRU and LRU_PERCPU hash maps bpf: Fix mask generation for 32-bit narrow loads of 64-bit fields samples/bpf: Drop unnecessary fallthrough bpf: netdev: init the offload table earlier selftests/bpf: Fix pkg-config call building sign-file ==================== Link: https://lore.kernel.org/r/20230524170839.13905-1-daniel@iogearbox.net Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-05-24udp: 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. Now that the scope is determined by ip_sendmsg_scope(), we need to check its result to set the 'connected' variable. Signed-off-by: Guillaume Nault <gnault@redhat.com> Reviewed-by: David Ahern <dsahern@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2023-05-24raw: 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>
2023-05-23udp: Convert udp_sendpage() to use MSG_SPLICE_PAGESDavid Howells
Convert udp_sendpage() to use sendmsg() with MSG_SPLICE_PAGES rather than directly splicing in the pages itself. This allows ->sendpage() to be replaced by something that can handle multiple multipage folios in a single transaction. 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>
2023-05-23ip, udp: Support MSG_SPLICE_PAGESDavid Howells
Make IP/UDP sendmsg() support MSG_SPLICE_PAGES. This causes pages to be spliced from the source iterator. This allows ->sendpage() to be replaced by something that can handle multiple multipage folios in a single transaction. 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>
2023-05-23tcp: Fold do_tcp_sendpages() into tcp_sendpage_locked()David Howells
Fold do_tcp_sendpages() into its last remaining caller, tcp_sendpage_locked(). Signed-off-by: David Howells <dhowells@redhat.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>
2023-05-23tcp_bpf: Inline do_tcp_sendpages as it's now a wrapper around tcp_sendmsgDavid Howells
do_tcp_sendpages() is now just a small wrapper around tcp_sendmsg_locked(), so inline it. This is part of replacing ->sendpage() with a call to sendmsg() with MSG_SPLICE_PAGES set. Signed-off-by: David Howells <dhowells@redhat.com> cc: John Fastabend <john.fastabend@gmail.com> cc: Jakub Sitnicki <jakub@cloudflare.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>
2023-05-23tcp: Convert do_tcp_sendpages() to use MSG_SPLICE_PAGESDavid Howells
Convert do_tcp_sendpages() to use sendmsg() with MSG_SPLICE_PAGES rather than directly splicing in the pages itself. do_tcp_sendpages() can then be inlined in subsequent patches into its callers. This allows ->sendpage() to be replaced by something that can handle multiple multipage folios in a single transaction. Signed-off-by: David Howells <dhowells@redhat.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>
2023-05-23tcp: Support MSG_SPLICE_PAGESDavid Howells
Make TCP's sendmsg() support MSG_SPLICE_PAGES. This causes pages to be spliced or copied (if it cannot be spliced) from the source iterator. This allows ->sendpage() to be replaced by something that can handle multiple multipage folios in a single transaction. Signed-off-by: David Howells <dhowells@redhat.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>
2023-05-23net: Pass max frags into skb_append_pagefrags()David Howells
Pass the maximum number of fragments into skb_append_pagefrags() rather than using MAX_SKB_FRAGS so that it can be used from code that wants to specify sysctl_max_skb_frags. Signed-off-by: David Howells <dhowells@redhat.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>
2023-05-23bpf, sockmap: Incorrectly handling copied_seqJohn Fastabend
The read_skb() logic is incrementing the tcp->copied_seq which is used for among other things calculating how many outstanding bytes can be read by the application. This results in application errors, if the application does an ioctl(FIONREAD) we return zero because this is calculated from the copied_seq value. To fix this we move tcp->copied_seq accounting into the recv handler so that we update these when the recvmsg() hook is called and data is in fact copied into user buffers. This gives an accurate FIONREAD value as expected and improves ACK handling. Before we were calling the tcp_rcv_space_adjust() which would update 'number of bytes copied to user in last RTT' which is wrong for programs returning SK_PASS. The bytes are only copied to the user when recvmsg is handled. Doing the fix for recvmsg is straightforward, but fixing redirect and SK_DROP pkts is a bit tricker. Build a tcp_psock_eat() helper and then call this from skmsg handlers. This fixes another issue where a broken socket with a BPF program doing a resubmit could hang the receiver. This happened because although read_skb() consumed the skb through sock_drop() it did not update the copied_seq. Now if a single reccv socket is redirecting to many sockets (for example for lb) the receiver sk will be hung even though we might expect it to continue. The hang comes from not updating the copied_seq numbers and memory pressure resulting from that. We have a slight layer problem of calling tcp_eat_skb even if its not a TCP socket. To fix we could refactor and create per type receiver handlers. I decided this is more work than we want in the fix and we already have some small tweaks depending on caller that use the helper skb_bpf_strparser(). So we extend that a bit and always set the strparser bit when it is in use and then we can gate the seq_copied updates on this. Fixes: 04919bed948dc ("tcp: Introduce tcp_read_skb()") Signed-off-by: John Fastabend <john.fastabend@gmail.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Reviewed-by: Jakub Sitnicki <jakub@cloudflare.com> Link: https://lore.kernel.org/bpf/20230523025618.113937-9-john.fastabend@gmail.com
2023-05-23bpf, sockmap: TCP data stall on recv before acceptJohn Fastabend
A common mechanism to put a TCP socket into the sockmap is to hook the BPF_SOCK_OPS_{ACTIVE_PASSIVE}_ESTABLISHED_CB event with a BPF program that can map the socket info to the correct BPF verdict parser. When the user adds the socket to the map the psock is created and the new ops are assigned to ensure the verdict program will 'see' the sk_buffs as they arrive. Part of this process hooks the sk_data_ready op with a BPF specific handler to wake up the BPF verdict program when data is ready to read. The logic is simple enough (posted here for easy reading) static void sk_psock_verdict_data_ready(struct sock *sk) { struct socket *sock = sk->sk_socket; if (unlikely(!sock || !sock->ops || !sock->ops->read_skb)) return; sock->ops->read_skb(sk, sk_psock_verdict_recv); } The oversight here is sk->sk_socket is not assigned until the application accepts() the new socket. However, its entirely ok for the peer application to do a connect() followed immediately by sends. The socket on the receiver is sitting on the backlog queue of the listening socket until its accepted and the data is queued up. If the peer never accepts the socket or is slow it will eventually hit data limits and rate limit the session. But, important for BPF sockmap hooks when this data is received TCP stack does the sk_data_ready() call but the read_skb() for this data is never called because sk_socket is missing. The data sits on the sk_receive_queue. Then once the socket is accepted if we never receive more data from the peer there will be no further sk_data_ready calls and all the data is still on the sk_receive_queue(). Then user calls recvmsg after accept() and for TCP sockets in sockmap we use the tcp_bpf_recvmsg_parser() handler. The handler checks for data in the sk_msg ingress queue expecting that the BPF program has already run from the sk_data_ready hook and enqueued the data as needed. So we are stuck. To fix do an unlikely check in recvmsg handler for data on the sk_receive_queue and if it exists wake up data_ready. We have the sock locked in both read_skb and recvmsg so should avoid having multiple runners. Fixes: 04919bed948dc ("tcp: Introduce tcp_read_skb()") Signed-off-by: John Fastabend <john.fastabend@gmail.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Reviewed-by: Jakub Sitnicki <jakub@cloudflare.com> Link: https://lore.kernel.org/bpf/20230523025618.113937-7-john.fastabend@gmail.com
2023-05-23bpf, sockmap: Handle fin correctlyJohn Fastabend
The sockmap code is returning EAGAIN after a FIN packet is received and no more data is on the receive queue. Correct behavior is to return 0 to the user and the user can then close the socket. The EAGAIN causes many apps to retry which masks the problem. Eventually the socket is evicted from the sockmap because its released from sockmap sock free handling. The issue creates a delay and can cause some errors on application side. To fix this check on sk_msg_recvmsg side if length is zero and FIN flag is set then set return to zero. A selftest will be added to check this condition. Fixes: 04919bed948dc ("tcp: Introduce tcp_read_skb()") Signed-off-by: John Fastabend <john.fastabend@gmail.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Tested-by: William Findlay <will@isovalent.com> Reviewed-by: Jakub Sitnicki <jakub@cloudflare.com> Link: https://lore.kernel.org/bpf/20230523025618.113937-6-john.fastabend@gmail.com
2023-05-23bpf, sockmap: Pass skb ownership through read_skbJohn Fastabend
The read_skb hook calls consume_skb() now, but this means that if the recv_actor program wants to use the skb it needs to inc the ref cnt so that the consume_skb() doesn't kfree the sk_buff. This is problematic because in some error cases under memory pressure we may need to linearize the sk_buff from sk_psock_skb_ingress_enqueue(). Then we get this, skb_linearize() __pskb_pull_tail() pskb_expand_head() BUG_ON(skb_shared(skb)) Because we incremented users refcnt from sk_psock_verdict_recv() we hit the bug on with refcnt > 1 and trip it. To fix lets simply pass ownership of the sk_buff through the skb_read call. Then we can drop the consume from read_skb handlers and assume the verdict recv does any required kfree. Bug found while testing in our CI which runs in VMs that hit memory constraints rather regularly. William tested TCP read_skb handlers. [ 106.536188] ------------[ cut here ]------------ [ 106.536197] kernel BUG at net/core/skbuff.c:1693! [ 106.536479] invalid opcode: 0000 [#1] PREEMPT SMP PTI [ 106.536726] CPU: 3 PID: 1495 Comm: curl Not tainted 5.19.0-rc5 #1 [ 106.537023] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS ArchLinux 1.16.0-1 04/01/2014 [ 106.537467] RIP: 0010:pskb_expand_head+0x269/0x330 [ 106.538585] RSP: 0018:ffffc90000138b68 EFLAGS: 00010202 [ 106.538839] RAX: 000000000000003f RBX: ffff8881048940e8 RCX: 0000000000000a20 [ 106.539186] RDX: 0000000000000002 RSI: 0000000000000000 RDI: ffff8881048940e8 [ 106.539529] RBP: ffffc90000138be8 R08: 00000000e161fd1a R09: 0000000000000000 [ 106.539877] R10: 0000000000000018 R11: 0000000000000000 R12: ffff8881048940e8 [ 106.540222] R13: 0000000000000003 R14: 0000000000000000 R15: ffff8881048940e8 [ 106.540568] FS: 00007f277dde9f00(0000) GS:ffff88813bd80000(0000) knlGS:0000000000000000 [ 106.540954] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 106.541227] CR2: 00007f277eeede64 CR3: 000000000ad3e000 CR4: 00000000000006e0 [ 106.541569] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 106.541915] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 106.542255] Call Trace: [ 106.542383] <IRQ> [ 106.542487] __pskb_pull_tail+0x4b/0x3e0 [ 106.542681] skb_ensure_writable+0x85/0xa0 [ 106.542882] sk_skb_pull_data+0x18/0x20 [ 106.543084] bpf_prog_b517a65a242018b0_bpf_skskb_http_verdict+0x3a9/0x4aa9 [ 106.543536] ? migrate_disable+0x66/0x80 [ 106.543871] sk_psock_verdict_recv+0xe2/0x310 [ 106.544258] ? sk_psock_write_space+0x1f0/0x1f0 [ 106.544561] tcp_read_skb+0x7b/0x120 [ 106.544740] tcp_data_queue+0x904/0xee0 [ 106.544931] tcp_rcv_established+0x212/0x7c0 [ 106.545142] tcp_v4_do_rcv+0x174/0x2a0 [ 106.545326] tcp_v4_rcv+0xe70/0xf60 [ 106.545500] ip_protocol_deliver_rcu+0x48/0x290 [ 106.545744] ip_local_deliver_finish+0xa7/0x150 Fixes: 04919bed948dc ("tcp: Introduce tcp_read_skb()") Reported-by: William Findlay <will@isovalent.com> Signed-off-by: John Fastabend <john.fastabend@gmail.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Tested-by: William Findlay <will@isovalent.com> Reviewed-by: Jakub Sitnicki <jakub@cloudflare.com> Link: https://lore.kernel.org/bpf/20230523025618.113937-2-john.fastabend@gmail.com
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>
2023-05-22net: ipconfig: move ic_nameservers_fallback into #ifdef blockArnd Bergmann
The new variable is only used when IPCONFIG_BOOTP is defined and otherwise causes a warning: net/ipv4/ipconfig.c:177:12: error: 'ic_nameservers_fallback' defined but not used [-Werror=unused-variable] Move it next to the user. Fixes: 81ac2722fa19 ("net: ipconfig: Allow DNS to be overwritten by DHCPACK") Signed-off-by: Arnd Bergmann <arnd@arndb.de> Reviewed-by: Simon Horman <simon.horman@corigine.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2023-05-19bpf: Add bpf_sock_destroy kfuncAditi Ghag
The socket destroy kfunc is used to forcefully terminate sockets from certain BPF contexts. We plan to use the capability in Cilium load-balancing to terminate client sockets that continue to connect to deleted backends. The other use case is on-the-fly policy enforcement where existing socket connections prevented by policies need to be forcefully terminated. The kfunc also allows terminating sockets that may or may not be actively sending traffic. The kfunc can currently be called only from BPF TCP and UDP iterators where users can filter, and terminate selected sockets. More specifically, it can only be called from BPF contexts that ensure socket locking in order to allow synchronous execution of protocol specific `diag_destroy` handlers. The previous commit that batches UDP sockets during iteration facilitated a synchronous invocation of the UDP destroy callback from BPF context by skipping socket locks in `udp_abort`. TCP iterator already supported batching of sockets being iterated. To that end, `tracing_iter_filter` callback filter is added so that verifier can restrict the kfunc to programs with `BPF_TRACE_ITER` attach type, and reject other programs. The kfunc takes `sock_common` type argument, even though it expects, and casts them to a `sock` pointer. This enables the verifier to allow the sock_destroy kfunc to be called for TCP with `sock_common` and UDP with `sock` structs. Furthermore, as `sock_common` only has a subset of certain fields of `sock`, casting pointer to the latter type might not always be safe for certain sockets like request sockets, but these have a special handling in the diag_destroy handlers. Additionally, the kfunc is defined with `KF_TRUSTED_ARGS` flag to avoid the cases where a `PTR_TO_BTF_ID` sk is obtained by following another pointer. eg. getting a sk pointer (may be even NULL) by following another sk pointer. The pointer socket argument passed in TCP and UDP iterators is tagged as `PTR_TRUSTED` in {tcp,udp}_reg_info. The TRUSTED arg changes are contributed by Martin KaFai Lau <martin.lau@kernel.org>. Signed-off-by: Aditi Ghag <aditi.ghag@isovalent.com> Link: https://lore.kernel.org/r/20230519225157.760788-8-aditi.ghag@isovalent.com Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
2023-05-19bpf: udp: Implement batching for sockets iteratorAditi Ghag
Batch UDP sockets from BPF iterator that allows for overlapping locking semantics in BPF/kernel helpers executed in BPF programs. This facilitates BPF socket destroy kfunc (introduced by follow-up patches) to execute from BPF iterator programs. Previously, BPF iterators acquired the sock lock and sockets hash table bucket lock while executing BPF programs. This prevented BPF helpers that again acquire these locks to be executed from BPF iterators. With the batching approach, we acquire a bucket lock, batch all the bucket sockets, and then release the bucket lock. This enables BPF or kernel helpers to skip sock locking when invoked in the supported BPF contexts. The batching logic is similar to the logic implemented in TCP iterator: https://lore.kernel.org/bpf/20210701200613.1036157-1-kafai@fb.com/. Suggested-by: Martin KaFai Lau <martin.lau@kernel.org> Signed-off-by: Aditi Ghag <aditi.ghag@isovalent.com> Link: https://lore.kernel.org/r/20230519225157.760788-6-aditi.ghag@isovalent.com Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
2023-05-19udp: seq_file: Remove bpf_seq_afinfo from udp_iter_stateAditi Ghag
This is a preparatory commit to remove the field. The field was previously shared between proc fs and BPF UDP socket iterators. As the follow-up commits will decouple the implementation for the iterators, remove the field. As for BPF socket iterator, filtering of sockets is exepected to be done in BPF programs. Suggested-by: Martin KaFai Lau <martin.lau@kernel.org> Signed-off-by: Aditi Ghag <aditi.ghag@isovalent.com> Link: https://lore.kernel.org/r/20230519225157.760788-5-aditi.ghag@isovalent.com Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
2023-05-19bpf: udp: Encapsulate logic to get udp tableAditi Ghag
This is a preparatory commit that encapsulates the logic to get udp table in iterator inside udp_get_table_afinfo, and renames the function to `udp_get_table_seq` accordingly. Suggested-by: Martin KaFai Lau <martin.lau@kernel.org> Signed-off-by: Aditi Ghag <aditi.ghag@isovalent.com> Link: https://lore.kernel.org/r/20230519225157.760788-4-aditi.ghag@isovalent.com Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
2023-05-19udp: seq_file: Helper function to match socket attributesAditi Ghag
This is a preparatory commit to refactor code that matches socket attributes in iterators to a helper function, and use it in the proc fs iterator. Signed-off-by: Aditi Ghag <aditi.ghag@isovalent.com> Link: https://lore.kernel.org/r/20230519225157.760788-3-aditi.ghag@isovalent.com Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
2023-05-19bpf: tcp: Avoid taking fast sock lock in iteratorAditi Ghag
This is a preparatory commit to replace `lock_sock_fast` with `lock_sock`,and facilitate BPF programs executed from the TCP sockets iterator to be able to destroy TCP sockets using the bpf_sock_destroy kfunc (implemented in follow-up commits). Previously, BPF TCP iterator was acquiring the sock lock with BH disabled. This led to scenarios where the sockets hash table bucket lock can be acquired with BH enabled in some path versus disabled in other. In such situation, kernel issued a warning since it thinks that in the BH enabled path the same bucket lock *might* be acquired again in the softirq context (BH disabled), which will lead to a potential dead lock. Since bpf_sock_destroy also happens in a process context, the potential deadlock warning is likely a false alarm. Here is a snippet of annotated stack trace that motivated this change: ``` Possible interrupt unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&h->lhash2[i].lock); local_bh_disable(); lock(&h->lhash2[i].lock); kernel imagined possible scenario: local_bh_disable(); /* Possible softirq */ lock(&h->lhash2[i].lock); *** Potential Deadlock *** process context: lock_acquire+0xcd/0x330 _raw_spin_lock+0x33/0x40 ------> Acquire (bucket) lhash2.lock with BH enabled __inet_hash+0x4b/0x210 inet_csk_listen_start+0xe6/0x100 inet_listen+0x95/0x1d0 __sys_listen+0x69/0xb0 __x64_sys_listen+0x14/0x20 do_syscall_64+0x3c/0x90 entry_SYSCALL_64_after_hwframe+0x72/0xdc bpf_sock_destroy run from iterator: lock_acquire+0xcd/0x330 _raw_spin_lock+0x33/0x40 ------> Acquire (bucket) lhash2.lock with BH disabled inet_unhash+0x9a/0x110 tcp_set_state+0x6a/0x210 tcp_abort+0x10d/0x200 bpf_prog_6793c5ca50c43c0d_iter_tcp6_server+0xa4/0xa9 bpf_iter_run_prog+0x1ff/0x340 ------> lock_sock_fast that acquires sock lock with BH disabled bpf_iter_tcp_seq_show+0xca/0x190 bpf_seq_read+0x177/0x450 ``` Also, Yonghong reported a deadlock for non-listening TCP sockets that this change resolves. Previously, `lock_sock_fast` held the sock spin lock with BH which was again being acquired in `tcp_abort`: ``` watchdog: BUG: soft lockup - CPU#0 stuck for 86s! [test_progs:2331] RIP: 0010:queued_spin_lock_slowpath+0xd8/0x500 Call Trace: <TASK> _raw_spin_lock+0x84/0x90 tcp_abort+0x13c/0x1f0 bpf_prog_88539c5453a9dd47_iter_tcp6_client+0x82/0x89 bpf_iter_run_prog+0x1aa/0x2c0 ? preempt_count_sub+0x1c/0xd0 ? from_kuid_munged+0x1c8/0x210 bpf_iter_tcp_seq_show+0x14e/0x1b0 bpf_seq_read+0x36c/0x6a0 bpf_iter_tcp_seq_show lock_sock_fast __lock_sock_fast spin_lock_bh(&sk->sk_lock.slock); /* * Fast path return with bottom halves disabled and * sock::sk_lock.slock held.* */ ... tcp_abort local_bh_disable(); spin_lock(&((sk)->sk_lock.slock)); // from bh_lock_sock(sk) ``` With the switch to `lock_sock`, it calls `spin_unlock_bh` before returning: ``` lock_sock lock_sock_nested spin_lock_bh(&sk->sk_lock.slock); : spin_unlock_bh(&sk->sk_lock.slock); ``` Acked-by: Yonghong Song <yhs@meta.com> Acked-by: Stanislav Fomichev <sdf@google.com> Signed-off-by: Aditi Ghag <aditi.ghag@isovalent.com> Link: https://lore.kernel.org/r/20230519225157.760788-2-aditi.ghag@isovalent.com Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
2023-05-18inet: factor out locked section of inet_accept() in a new helperPaolo Abeni
No functional changes intended. The new helper will be used by the MPTCP protocol in the next patch to avoid duplicating a few LoC. Signed-off-by: Paolo Abeni <pabeni@redhat.com> Reviewed-by: Matthieu Baerts <matthieu.baerts@tessares.net> Signed-off-by: Mat Martineau <martineau@kernel.org> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-05-18Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netJakub Kicinski
Conflicts: drivers/net/ethernet/freescale/fec_main.c 6ead9c98cafc ("net: fec: remove the xdp_return_frame when lack of tx BDs") 144470c88c5d ("net: fec: using the standard return codes when xdp xmit errors") Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-05-17net/tcp: optimise io_uring zc ubuf refcountingPavel Begunkov
io_uring keeps a reference to ubuf_info during submission, so if tcp_sendmsg_locked() sees msghdr::msg_ubuf in can be sure the buffer will be kept alive and doesn't need to additionally pin it. Signed-off-by: Pavel Begunkov <asml.silence@gmail.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2023-05-17net/tcp: don't peek at tail for io_uring zcPavel Begunkov
Move tcp_write_queue_tail() to SOCK_ZEROCOPY specific flag as zerocopy setup for msghdr->ubuf_info doesn't need to peek into the last request. Signed-off-by: Pavel Begunkov <asml.silence@gmail.com> Reviewed-by: David Ahern <dsahern@kernel.org> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2023-05-16Revert "net: Remove low_thresh in ip defrag"Jakub Kicinski
This reverts commit b2cbac9b9b28730e9e53be20b6cdf979d3b9f27e. We have multiple reports of obvious breakage from this patch. Reported-by: Ido Schimmel <idosch@idosch.org> Link: https://lore.kernel.org/all/ZGIRWjNcfqI8yY8W@shredder/ Link: https://lore.kernel.org/all/CADJHv_sDK=0RrMA2FTZQV5fw7UQ+qY=HG21Wu5qb0V9vvx5w6A@mail.gmail.com/ Reported-by: syzbot+a5e719ac7c268e414c95@syzkaller.appspotmail.com Reported-by: syzbot+a03fd670838d927d9cd8@syzkaller.appspotmail.com Fixes: b2cbac9b9b28 ("net: Remove low_thresh in ip defrag") Link: https://lore.kernel.org/r/20230517034112.1261835-1-kuba@kernel.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-05-15net: Remove low_thresh in ip defragAngus Chen
As low_thresh has no work in fragment reassembles,del it. And Mark it deprecated in sysctl Document. Signed-off-by: Angus Chen <angus.chen@jaguarmicro.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2023-05-13ping: Convert hlist_nulls to plain hlist.Kuniyuki Iwashima
Since introduced in commit c319b4d76b9e ("net: ipv4: add IPPROTO_ICMP socket kind"), ping socket does not use SLAB_TYPESAFE_BY_RCU nor check nulls marker in loops. Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Reviewed-by: Simon Horman <simon.horman@corigine.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2023-05-12tcp: fix possible sk_priority leak in tcp_v4_send_reset()Eric Dumazet
When tcp_v4_send_reset() is called with @sk == NULL, we do not change ctl_sk->sk_priority, which could have been set from a prior invocation. Change tcp_v4_send_reset() to set sk_priority and sk_mark fields before calling ip_send_unicast_reply(). This means tcp_v4_send_reset() and tcp_v4_send_ack() no longer have to clear ctl_sk->sk_mark after their call to ip_send_unicast_reply(). Fixes: f6c0f5d209fa ("tcp: honor SO_PRIORITY in TIME_WAIT state") Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Antoine Tenart <atenart@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2023-05-11Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netJakub Kicinski
Cross-merge networking fixes. No conflicts. Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-05-11tcp: make the first N SYN RTO backoffs linearDavid Morley
Currently the SYN RTO schedule follows an exponential backoff scheme, which can be unnecessarily conservative in cases where there are link failures. In such cases, it's better to aggressively try to retransmit packets, so it takes routers less time to find a repath with a working link. We chose a default value for this sysctl of 4, to follow the macOS and IOS backoff scheme of 1,1,1,1,1,2,4,8, ... MacOS and IOS have used this backoff schedule for over a decade, since before this 2009 IETF presentation discussed the behavior: https://www.ietf.org/proceedings/75/slides/tcpm-1.pdf This commit makes the SYN RTO schedule start with a number of linear backoffs given by the following sysctl: * tcp_syn_linear_timeouts This changes the SYN RTO scheme to be: init_rto_val for tcp_syn_linear_timeouts, exp backoff starting at init_rto_val For example if init_rto_val = 1 and tcp_syn_linear_timeouts = 2, our backoff scheme would be: 1, 1, 1, 2, 4, 8, 16, ... Signed-off-by: David Morley <morleyd@google.com> Signed-off-by: Yuchung Cheng <ycheng@google.com> Signed-off-by: Neal Cardwell <ncardwell@google.com> Tested-by: David Morley <morleyd@google.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Link: https://lore.kernel.org/r/20230509180558.2541885-1-morleyd.kernel@gmail.com Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2023-05-10tcp: add annotations around sk->sk_shutdown accessesEric Dumazet
Now sk->sk_shutdown is no longer a bitfield, we can add standard READ_ONCE()/WRITE_ONCE() annotations to silence KCSAN reports like the following: BUG: KCSAN: data-race in tcp_disconnect / tcp_poll write to 0xffff88814588582c of 1 bytes by task 3404 on cpu 1: tcp_disconnect+0x4d6/0xdb0 net/ipv4/tcp.c:3121 __inet_stream_connect+0x5dd/0x6e0 net/ipv4/af_inet.c:715 inet_stream_connect+0x48/0x70 net/ipv4/af_inet.c:727 __sys_connect_file net/socket.c:2001 [inline] __sys_connect+0x19b/0x1b0 net/socket.c:2018 __do_sys_connect net/socket.c:2028 [inline] __se_sys_connect net/socket.c:2025 [inline] __x64_sys_connect+0x41/0x50 net/socket.c:2025 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 0xffff88814588582c of 1 bytes by task 3374 on cpu 0: tcp_poll+0x2e6/0x7d0 net/ipv4/tcp.c:562 sock_poll+0x253/0x270 net/socket.c:1383 vfs_poll include/linux/poll.h:88 [inline] io_poll_check_events io_uring/poll.c:281 [inline] io_poll_task_func+0x15a/0x820 io_uring/poll.c:333 handle_tw_list io_uring/io_uring.c:1184 [inline] tctx_task_work+0x1fe/0x4d0 io_uring/io_uring.c:1246 task_work_run+0x123/0x160 kernel/task_work.c:179 get_signal+0xe64/0xff0 kernel/signal.c:2635 arch_do_signal_or_restart+0x89/0x2a0 arch/x86/kernel/signal.c:306 exit_to_user_mode_loop+0x6f/0xe0 kernel/entry/common.c:168 exit_to_user_mode_prepare+0x6c/0xb0 kernel/entry/common.c:204 __syscall_exit_to_user_mode_work kernel/entry/common.c:286 [inline] syscall_exit_to_user_mode+0x26/0x140 kernel/entry/common.c:297 do_syscall_64+0x4d/0xc0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x63/0xcd value changed: 0x03 -> 0x00 Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Reported-by: syzbot <syzkaller@googlegroups.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2023-05-10net: deal with most data-races in sk_wait_event()Eric Dumazet
__condition is evaluated twice in sk_wait_event() macro. First invocation is lockless, and reads can race with writes, as spotted by syzbot. BUG: KCSAN: data-race in sk_stream_wait_connect / tcp_disconnect write to 0xffff88812d83d6a0 of 4 bytes by task 9065 on cpu 1: tcp_disconnect+0x2cd/0xdb0 inet_shutdown+0x19e/0x1f0 net/ipv4/af_inet.c:911 __sys_shutdown_sock net/socket.c:2343 [inline] __sys_shutdown net/socket.c:2355 [inline] __do_sys_shutdown net/socket.c:2363 [inline] __se_sys_shutdown+0xf8/0x140 net/socket.c:2361 __x64_sys_shutdown+0x31/0x40 net/socket.c:2361 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 0xffff88812d83d6a0 of 4 bytes by task 9040 on cpu 0: sk_stream_wait_connect+0x1de/0x3a0 net/core/stream.c:75 tcp_sendmsg_locked+0x2e4/0x2120 net/ipv4/tcp.c:1266 tcp_sendmsg+0x30/0x50 net/ipv4/tcp.c:1484 inet6_sendmsg+0x63/0x80 net/ipv6/af_inet6.c:651 sock_sendmsg_nosec net/socket.c:724 [inline] sock_sendmsg net/socket.c:747 [inline] __sys_sendto+0x246/0x300 net/socket.c:2142 __do_sys_sendto net/socket.c:2154 [inline] __se_sys_sendto net/socket.c:2150 [inline] __x64_sys_sendto+0x78/0x90 net/socket.c:2150 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: 0x00000000 -> 0x00000068 Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Reported-by: syzbot <syzkaller@googlegroups.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2023-05-10net: ipconfig: Allow DNS to be overwritten by DHCPACKMartin Wetterwald
Some DHCP server implementations only send the important requested DHCP options in the final BOOTP reply (DHCPACK). One example is systemd-networkd. However, RFC2131, in section 4.3.1 states: > The server MUST return to the client: > [...] > o Parameters requested by the client, according to the following > rules: > > -- IF the server has been explicitly configured with a default > value for the parameter, the server MUST include that value > in an appropriate option in the 'option' field, ELSE I've reported the issue here: https://github.com/systemd/systemd/issues/27471 Linux PNP DHCP client implementation only takes into account the DNS servers received in the first BOOTP reply (DHCPOFFER). This usually isn't an issue as servers are required to put the same values in the DHCPOFFER and DHCPACK. However, RFC2131, in section 4.3.2 states: > Any configuration parameters in the DHCPACK message SHOULD NOT > conflict with those in the earlier DHCPOFFER message to which the > client is responding. The client SHOULD use the parameters in the > DHCPACK message for configuration. When making Linux PNP DHCP client (cmdline ip=dhcp) interact with systemd-networkd DHCP server, an interesting "protocol misunderstanding" happens: Because DNS servers were only specified in the DHCPACK and not in the DHCPOFFER, Linux will not catch the correct DNS servers: in the first BOOTP reply (DHCPOFFER), it sees that there is no DNS, and sets as fallback the IP of the DHCP server itself. When the second BOOTP reply comes (DHCPACK), it's already too late: the kernel will not overwrite the fallback setting it has set previously. This patch makes the kernel overwrite its DNS fallback by DNS servers specified in the DHCPACK if any. Signed-off-by: Martin Wetterwald <martin@wetterwald.eu> Signed-off-by: David S. Miller <davem@davemloft.net>
2023-04-26Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netPaolo Abeni
No conflicts. Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2023-04-22ipv4: Fix potential uninit variable access bug in __ip_make_skb()Ziyang Xuan
Like commit ea30388baebc ("ipv6: Fix an uninit variable access bug in __ip6_make_skb()"). icmphdr does not in skb linear region under the scenario of SOCK_RAW socket. Access icmp_hdr(skb)->type directly will trigger the uninit variable access bug. Use a local variable icmp_type to carry the correct value in different scenarios. Fixes: 96793b482540 ("[IPV4]: Add ICMPMsgStats MIB (RFC 4293)") Reviewed-by: Willem de Bruijn <willemb@google.com> Signed-off-by: Ziyang Xuan <william.xuanziyang@huawei.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2023-04-21net: dst: fix missing initialization of rt_uncachedMaxime Bizon
xfrm_alloc_dst() followed by xfrm4_dst_destroy(), without a xfrm4_fill_dst() call in between, causes the following BUG: BUG: spinlock bad magic on CPU#0, fbxhostapd/732 lock: 0x890b7668, .magic: 890b7668, .owner: <none>/-1, .owner_cpu: 0 CPU: 0 PID: 732 Comm: fbxhostapd Not tainted 6.3.0-rc6-next-20230414-00613-ge8de66369925-dirty #9 Hardware name: Marvell Kirkwood (Flattened Device Tree) unwind_backtrace from show_stack+0x10/0x14 show_stack from dump_stack_lvl+0x28/0x30 dump_stack_lvl from do_raw_spin_lock+0x20/0x80 do_raw_spin_lock from rt_del_uncached_list+0x30/0x64 rt_del_uncached_list from xfrm4_dst_destroy+0x3c/0xbc xfrm4_dst_destroy from dst_destroy+0x5c/0xb0 dst_destroy from rcu_process_callbacks+0xc4/0xec rcu_process_callbacks from __do_softirq+0xb4/0x22c __do_softirq from call_with_stack+0x1c/0x24 call_with_stack from do_softirq+0x60/0x6c do_softirq from __local_bh_enable_ip+0xa0/0xcc Patch "net: dst: Prevent false sharing vs. dst_entry:: __refcnt" moved rt_uncached and rt_uncached_list fields from rtable struct to dst struct, so they are more zeroed by memset_after(xdst, 0, u.dst) in xfrm_alloc_dst(). Note that rt_uncached (list_head) was never properly initialized at alloc time, but xfrm[46]_dst_destroy() is written in such a way that it was not an issue thanks to the memset: if (xdst->u.rt.dst.rt_uncached_list) rt_del_uncached_list(&xdst->u.rt); The route code does it the other way around: rt_uncached_list is assumed to be valid IIF rt_uncached list_head is not empty: void rt_del_uncached_list(struct rtable *rt) { if (!list_empty(&rt->dst.rt_uncached)) { struct uncached_list *ul = rt->dst.rt_uncached_list; spin_lock_bh(&ul->lock); list_del_init(&rt->dst.rt_uncached); spin_unlock_bh(&ul->lock); } } This patch adds mandatory rt_uncached list_head initialization in generic dst_init(), and adapt xfrm[46]_dst_destroy logic to match the rest of the code. Fixes: d288a162dd1c ("net: dst: Prevent false sharing vs. dst_entry:: __refcnt") Reported-by: kernel test robot <oliver.sang@intel.com> Link: https://lore.kernel.org/oe-lkp/202304162125.18b7bcdd-oliver.sang@intel.com Reviewed-by: David Ahern <dsahern@kernel.org> Reviewed-by: Eric Dumazet <edumazet@google.com> CC: Leon Romanovsky <leon@kernel.org> Signed-off-by: Maxime Bizon <mbizon@freebox.fr> Link: https://lore.kernel.org/r/20230420182508.2417582-1-mbizon@freebox.fr Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-04-14net: Ensure ->msg_control_user is used for user buffersKevin Brodsky
Since commit 1f466e1f15cf ("net: cleanly handle kernel vs user buffers for ->msg_control"), pointers to user buffers should be stored in struct msghdr::msg_control_user, instead of the msg_control field. Most users of msg_control have already been converted (where user buffers are involved), but not all of them. This patch attempts to address the remaining cases. An exception is made for null checks, as it should be safe to use msg_control unconditionally for that purpose. Cc: Christoph Hellwig <hch@lst.de> Cc: Eric Dumazet <edumazet@google.com> Cc: "David S. Miller" <davem@davemloft.net> Cc: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Kevin Brodsky <kevin.brodsky@arm.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: David S. Miller <davem@davemloft.net>
2023-04-13Daniel Borkmann says:Jakub Kicinski
==================== pull-request: bpf-next 2023-04-13 We've added 260 non-merge commits during the last 36 day(s) which contain a total of 356 files changed, 21786 insertions(+), 11275 deletions(-). The main changes are: 1) Rework BPF verifier log behavior and implement it as a rotating log by default with the option to retain old-style fixed log behavior, from Andrii Nakryiko. 2) Adds support for using {FOU,GUE} encap with an ipip device operating in collect_md mode and add a set of BPF kfuncs for controlling encap params, from Christian Ehrig. 3) Allow BPF programs to detect at load time whether a particular kfunc exists or not, and also add support for this in light skeleton, from Alexei Starovoitov. 4) Optimize hashmap lookups when key size is multiple of 4, from Anton Protopopov. 5) Enable RCU semantics for task BPF kptrs and allow referenced kptr tasks to be stored in BPF maps, from David Vernet. 6) Add support for stashing local BPF kptr into a map value via bpf_kptr_xchg(). This is useful e.g. for rbtree node creation for new cgroups, from Dave Marchevsky. 7) Fix BTF handling of is_int_ptr to skip modifiers to work around tracing issues where a program cannot be attached, from Feng Zhou. 8) Migrate a big portion of test_verifier unit tests over to test_progs -a verifier_* via inline asm to ease {read,debug}ability, from Eduard Zingerman. 9) Several updates to the instruction-set.rst documentation which is subject to future IETF standardization (https://lwn.net/Articles/926882/), from Dave Thaler. 10) Fix BPF verifier in the __reg_bound_offset's 64->32 tnum sub-register known bits information propagation, from Daniel Borkmann. 11) Add skb bitfield compaction work related to BPF with the overall goal to make more of the sk_buff bits optional, from Jakub Kicinski. 12) BPF selftest cleanups for build id extraction which stand on its own from the upcoming integration work of build id into struct file object, from Jiri Olsa. 13) Add fixes and optimizations for xsk descriptor validation and several selftest improvements for xsk sockets, from Kal Conley. 14) Add BPF links for struct_ops and enable switching implementations of BPF TCP cong-ctls under a given name by replacing backing struct_ops map, from Kui-Feng Lee. 15) Remove a misleading BPF verifier env->bypass_spec_v1 check on variable offset stack read as earlier Spectre checks cover this, from Luis Gerhorst. 16) Fix issues in copy_from_user_nofault() for BPF and other tracers to resemble copy_from_user_nmi() from safety PoV, from Florian Lehner and Alexei Starovoitov. 17) Add --json-summary option to test_progs in order for CI tooling to ease parsing of test results, from Manu Bretelle. 18) Batch of improvements and refactoring to prep for upcoming bpf_local_storage conversion to bpf_mem_cache_{alloc,free} allocator, from Martin KaFai Lau. 19) Improve bpftool's visual program dump which produces the control flow graph in a DOT format by adding C source inline annotations, from Quentin Monnet. 20) Fix attaching fentry/fexit/fmod_ret/lsm to modules by extracting the module name from BTF of the target and searching kallsyms of the correct module, from Viktor Malik. 21) Improve BPF verifier handling of '<const> <cond> <non_const>' to better detect whether in particular jmp32 branches are taken, from Yonghong Song. 22) Allow BPF TCP cong-ctls to write app_limited of struct tcp_sock. A built-in cc or one from a kernel module is already able to write to app_limited, from Yixin Shen. Conflicts: Documentation/bpf/bpf_devel_QA.rst b7abcd9c656b ("bpf, doc: Link to submitting-patches.rst for general patch submission info") 0f10f647f455 ("bpf, docs: Use internal linking for link to netdev subsystem doc") https://lore.kernel.org/all/20230307095812.236eb1be@canb.auug.org.au/ include/net/ip_tunnels.h bc9d003dc48c3 ("ip_tunnel: Preserve pointer const in ip_tunnel_info_opts") ac931d4cdec3d ("ipip,ip_tunnel,sit: Add FOU support for externally controlled ipip devices") https://lore.kernel.org/all/20230413161235.4093777-1-broonie@kernel.org/ net/bpf/test_run.c e5995bc7e2ba ("bpf, test_run: fix crashes due to XDP frame overwriting/corruption") 294635a8165a ("bpf, test_run: fix &xdp_frame misplacement for LIVE_FRAMES") https://lore.kernel.org/all/20230320102619.05b80a98@canb.auug.org.au/ ==================== Link: https://lore.kernel.org/r/20230413191525.7295-1-daniel@iogearbox.net Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-04-13Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netJakub Kicinski
Conflicts: tools/testing/selftests/net/config 62199e3f1658 ("selftests: net: Add VXLAN MDB test") 3a0385be133e ("selftests: add the missing CONFIG_IP_SCTP in net config") Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-04-12bpf,fou: Add bpf_skb_{set,get}_fou_encap kfuncsChristian Ehrig
Add two new kfuncs that allow a BPF tc-hook, installed on an ipip device in collect-metadata mode, to control FOU encap parameters on a per-packet level. The set of kfuncs is registered with the fou module. The bpf_skb_set_fou_encap kfunc is supposed to be used in tandem and after a successful call to the bpf_skb_set_tunnel_key bpf-helper. UDP source and destination ports can be controlled by passing a struct bpf_fou_encap. A source port of zero will auto-assign a source port. enum bpf_fou_encap_type is used to specify if the egress path should FOU or GUE encap the packet. On the ingress path bpf_skb_get_fou_encap can be used to read UDP source and destination ports from the receiver's point of view and allows for packet multiplexing across different destination ports within a single BPF program and ipip device. Signed-off-by: Christian Ehrig <cehrig@cloudflare.com> Link: https://lore.kernel.org/r/e17c94a646b63e78ce0dbf3f04b2c33dc948a32d.1680874078.git.cehrig@cloudflare.com Signed-off-by: Alexei Starovoitov <ast@kernel.org>