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* sock: redo the psock vs ULP protection checkJakub Kicinski2022-06-231-0/+5
| | | | | | | | | | | | | | | | | | | | | | Commit 8a59f9d1e3d4 ("sock: Introduce sk->sk_prot->psock_update_sk_prot()") has moved the inet_csk_has_ulp(sk) check from sk_psock_init() to the new tcp_bpf_update_proto() function. I'm guessing that this was done to allow creating psocks for non-inet sockets. Unfortunately the destruction path for psock includes the ULP unwind, so we need to fail the sk_psock_init() itself. Otherwise if ULP is already present we'll notice that later, and call tcp_update_ulp() with the sk_proto of the ULP itself, which will most likely result in the ULP looping its callbacks. Fixes: 8a59f9d1e3d4 ("sock: Introduce sk->sk_prot->psock_update_sk_prot()") Signed-off-by: Jakub Kicinski <kuba@kernel.org> Reviewed-by: John Fastabend <john.fastabend@gmail.com> Reviewed-by: Jakub Sitnicki <jakub@cloudflare.com> Tested-by: Jakub Sitnicki <jakub@cloudflare.com> Link: https://lore.kernel.org/r/20220620191353.1184629-2-kuba@kernel.org Signed-off-by: Paolo Abeni <pabeni@redhat.com>
* bpf, sockmap: Call skb_linearize only when required in ↵Liu Jian2022-04-281-9/+13
| | | | | | | | | | | | | sk_psock_skb_ingress_enqueue The skb_to_sgvec fails only when the number of frag_list and frags exceeds MAX_MSG_FRAGS. Therefore, we can call skb_linearize only when the conversion fails. Signed-off-by: Liu Jian <liujian56@huawei.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: John Fastabend <john.fastabend@gmail.com> Link: https://lore.kernel.org/bpf/20220427115150.210213-1-liujian56@huawei.com
* bpf, sockmap: Fix memleak in tcp_bpf_sendmsg while sk msg is fullWang Yufen2022-03-151-4/+13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If tcp_bpf_sendmsg() is running while sk msg is full. When sk_msg_alloc() returns -ENOMEM error, tcp_bpf_sendmsg() goes to wait_for_memory. If partial memory has been alloced by sk_msg_alloc(), that is, msg_tx->sg.size is greater than osize after sk_msg_alloc(), memleak occurs. To fix we use sk_msg_trim() to release the allocated memory, then goto wait for memory. Other call paths of sk_msg_alloc() have the similar issue, such as tls_sw_sendmsg(), so handle sk_msg_trim logic inside sk_msg_alloc(), as Cong Wang suggested. This issue can cause the following info: WARNING: CPU: 3 PID: 7950 at net/core/stream.c:208 sk_stream_kill_queues+0xd4/0x1a0 Call Trace: <TASK> inet_csk_destroy_sock+0x55/0x110 __tcp_close+0x279/0x470 tcp_close+0x1f/0x60 inet_release+0x3f/0x80 __sock_release+0x3d/0xb0 sock_close+0x11/0x20 __fput+0x92/0x250 task_work_run+0x6a/0xa0 do_exit+0x33b/0xb60 do_group_exit+0x2f/0xa0 get_signal+0xb6/0x950 arch_do_signal_or_restart+0xac/0x2a0 exit_to_user_mode_prepare+0xa9/0x200 syscall_exit_to_user_mode+0x12/0x30 do_syscall_64+0x46/0x80 entry_SYSCALL_64_after_hwframe+0x44/0xae </TASK> WARNING: CPU: 3 PID: 2094 at net/ipv4/af_inet.c:155 inet_sock_destruct+0x13c/0x260 Call Trace: <TASK> __sk_destruct+0x24/0x1f0 sk_psock_destroy+0x19b/0x1c0 process_one_work+0x1b3/0x3c0 kthread+0xe6/0x110 ret_from_fork+0x22/0x30 </TASK> Fixes: 604326b41a6f ("bpf, sockmap: convert to generic sk_msg interface") Signed-off-by: Wang Yufen <wangyufen@huawei.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: John Fastabend <john.fastabend@gmail.com> Link: https://lore.kernel.org/bpf/20220304081145.2037182-3-wangyufen@huawei.com
* bpf, sockmap: Do not ignore orig_len parameterEric Dumazet2022-03-021-1/+1
| | | | | | | | | | | | | | | | | | | | | Currently, sk_psock_verdict_recv() returns skb->len This is problematic because tcp_read_sock() might have passed orig_len < skb->len, due to the presence of TCP urgent data. This causes an infinite loop from tcp_read_sock() Followup patch will make tcp_read_sock() more robust vs bad actors. Fixes: ef5659280eb1 ("bpf, sockmap: Allow skipping sk_skb parser program") Reported-by: syzbot <syzkaller@googlegroups.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Acked-by: John Fastabend <john.fastabend@gmail.com> Acked-by: Jakub Sitnicki <jakub@cloudflare.com> Tested-by: Jakub Sitnicki <jakub@cloudflare.com> Acked-by: Daniel Borkmann <daniel@iogearbox.net> Link: https://lore.kernel.org/r/20220302161723.3910001-1-eric.dumazet@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
* bpf, sockmap: Re-evaluate proto ops when psock is removed from sockmapJohn Fastabend2021-11-201-0/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When a sock is added to a sock map we evaluate what proto op hooks need to be used. However, when the program is removed from the sock map we have not been evaluating if that changes the required program layout. Before the patch listed in the 'fixes' tag this was not causing failures because the base program set handles all cases. Specifically, the case with a stream parser and the case with out a stream parser are both handled. With the fix below we identified a race when running with a proto op that attempts to read skbs off both the stream parser and the skb->receive_queue. Namely, that a race existed where when the stream parser is empty checking the skb->receive_queue from recvmsg at the precies moment when the parser is paused and the receive_queue is not empty could result in skipping the stream parser. This may break a RX policy depending on the parser to run. The fix tag then loads a specific proto ops that resolved this race. But, we missed removing that proto ops recv hook when the sock is removed from the sockmap. The result is the stream parser is stopped so no more skbs will be aggregated there, but the hook and BPF program continues to be attached on the psock. User space will then get an EBUSY when trying to read the socket because the recvmsg() handler is now waiting on a stopped stream parser. To fix we rerun the proto ops init() function which will look at the new set of progs attached to the psock and rest the proto ops hook to the correct handlers. And in the above case where we remove the sock from the sock map the RX prog will no longer be listed so the proto ops is removed. Fixes: c5d2177a72a16 ("bpf, sockmap: Fix race in ingress receive verdict with redirect to self") Signed-off-by: John Fastabend <john.fastabend@gmail.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Link: https://lore.kernel.org/bpf/20211119181418.353932-3-john.fastabend@gmail.com
* Merge https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-nextJakub Kicinski2021-11-011-10/+33
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Alexei Starovoitov says: ==================== pull-request: bpf-next 2021-11-01 We've added 181 non-merge commits during the last 28 day(s) which contain a total of 280 files changed, 11791 insertions(+), 5879 deletions(-). The main changes are: 1) Fix bpf verifier propagation of 64-bit bounds, from Alexei. 2) Parallelize bpf test_progs, from Yucong and Andrii. 3) Deprecate various libbpf apis including af_xdp, from Andrii, Hengqi, Magnus. 4) Improve bpf selftests on s390, from Ilya. 5) bloomfilter bpf map type, from Joanne. 6) Big improvements to JIT tests especially on Mips, from Johan. 7) Support kernel module function calls from bpf, from Kumar. 8) Support typeless and weak ksym in light skeleton, from Kumar. 9) Disallow unprivileged bpf by default, from Pawan. 10) BTF_KIND_DECL_TAG support, from Yonghong. 11) Various bpftool cleanups, from Quentin. * https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (181 commits) libbpf: Deprecate AF_XDP support kbuild: Unify options for BTF generation for vmlinux and modules selftests/bpf: Add a testcase for 64-bit bounds propagation issue. bpf: Fix propagation of signed bounds from 64-bit min/max into 32-bit. bpf: Fix propagation of bounds from 64-bit min/max into 32-bit and var_off. selftests/bpf: Fix also no-alu32 strobemeta selftest bpf: Add missing map_delete_elem method to bloom filter map selftests/bpf: Add bloom map success test for userspace calls bpf: Add alignment padding for "map_extra" + consolidate holes bpf: Bloom filter map naming fixups selftests/bpf: Add test cases for struct_ops prog bpf: Add dummy BPF STRUCT_OPS for test purpose bpf: Factor out helpers for ctx access checking bpf: Factor out a helper to prepare trampoline for struct_ops prog selftests, bpf: Fix broken riscv build riscv, libbpf: Add RISC-V (RV64) support to bpf_tracing.h tools, build: Add RISC-V to HOSTARCH parsing riscv, bpf: Increase the maximum number of iterations selftests, bpf: Add one test for sockmap with strparser selftests, bpf: Fix test_txmsg_ingress_parser error ... ==================== Link: https://lore.kernel.org/r/20211102013123.9005-1-alexei.starovoitov@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
| * skmsg: Lose offset info in sk_psock_skb_ingressLiu Jian2021-11-011-10/+33
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If sockmap enable strparser, there are lose offset info in sk_psock_skb_ingress(). If the length determined by parse_msg function is not skb->len, the skb will be converted to sk_msg multiple times, and userspace app will get the data multiple times. Fix this by get the offset and length from strp_msg. And as Cong suggested, add one bit in skb->_sk_redir to distinguish enable or disable strparser. Fixes: 604326b41a6fb ("bpf, sockmap: convert to generic sk_msg interface") Signed-off-by: Liu Jian <liujian56@huawei.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Reviewed-by: Cong Wang <cong.wang@bytedance.com> Acked-by: John Fastabend <john.fastabend@gmail.com> Link: https://lore.kernel.org/bpf/20211029141216.211899-1-liujian56@huawei.com
* | skmsg: Extract and reuse sk_msg_is_readable()Cong Wang2021-10-261-0/+14
|/ | | | | | | | | 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 <cong.wang@bytedance.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/20211008203306.37525-3-xiyou.wangcong@gmail.com
* bpf, sockmap: Fix memleak on ingress msg enqueueJohn Fastabend2021-07-271-6/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If backlog handler is running during a tear down operation we may enqueue data on the ingress msg queue while tear down is trying to free it. sk_psock_backlog() sk_psock_handle_skb() skb_psock_skb_ingress() sk_psock_skb_ingress_enqueue() sk_psock_queue_msg(psock,msg) spin_lock(ingress_lock) sk_psock_zap_ingress() _sk_psock_purge_ingerss_msg() _sk_psock_purge_ingress_msg() -- free ingress_msg list -- spin_unlock(ingress_lock) spin_lock(ingress_lock) list_add_tail(msg,ingress_msg) <- entry on list with no one left to free it. spin_unlock(ingress_lock) To fix we only enqueue from backlog if the ENABLED bit is set. The tear down logic clears the bit with ingress_lock set so we wont enqueue the msg in the last step. Fixes: 799aa7f98d53 ("skmsg: Avoid lock_sock() in sk_psock_backlog()") Signed-off-by: John Fastabend <john.fastabend@gmail.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Acked-by: Jakub Sitnicki <jakub@cloudflare.com> Acked-by: Martin KaFai Lau <kafai@fb.com> Link: https://lore.kernel.org/bpf/20210727160500.1713554-4-john.fastabend@gmail.com
* bpf, sockmap: On cleanup we additionally need to remove cached skbJohn Fastabend2021-07-271-6/+29
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Its possible if a socket is closed and the receive thread is under memory pressure it may have cached a skb. We need to ensure these skbs are free'd along with the normal ingress_skb queue. Before 799aa7f98d53 ("skmsg: Avoid lock_sock() in sk_psock_backlog()") tear down and backlog processing both had sock_lock for the common case of socket close or unhash. So it was not possible to have both running in parrallel so all we would need is the kfree in those kernels. But, latest kernels include the commit 799aa7f98d5e and this requires a bit more work. Without the ingress_lock guarding reading/writing the state->skb case its possible the tear down could run before the state update causing it to leak memory or worse when the backlog reads the state it could potentially run interleaved with the tear down and we might end up free'ing the state->skb from tear down side but already have the reference from backlog side. To resolve such races we wrap accesses in ingress_lock on both sides serializing tear down and backlog case. In both cases this only happens after an EAGAIN error case so having an extra lock in place is likely fine. The normal path will skip the locks. Note, we check state->skb before grabbing lock. This works because we can only enqueue with the mutex we hold already. Avoiding a race on adding state->skb after the check. And if tear down path is running that is also fine if the tear down path then removes state->skb we will simply set skb=NULL and the subsequent goto is skipped. This slight complication avoids locking in normal case. With this fix we no longer see this warning splat from tcp side on socket close when we hit the above case with redirect to ingress self. [224913.935822] WARNING: CPU: 3 PID: 32100 at net/core/stream.c:208 sk_stream_kill_queues+0x212/0x220 [224913.935841] Modules linked in: fuse overlay bpf_preload x86_pkg_temp_thermal intel_uncore wmi_bmof squashfs sch_fq_codel efivarfs ip_tables x_tables uas xhci_pci ixgbe mdio xfrm_algo xhci_hcd wmi [224913.935897] CPU: 3 PID: 32100 Comm: fgs-bench Tainted: G I 5.14.0-rc1alu+ #181 [224913.935908] Hardware name: Dell Inc. Precision 5820 Tower/002KVM, BIOS 1.9.2 01/24/2019 [224913.935914] RIP: 0010:sk_stream_kill_queues+0x212/0x220 [224913.935923] Code: 8b 83 20 02 00 00 85 c0 75 20 5b 5d 41 5c 41 5d 41 5e 41 5f c3 48 89 df e8 2b 11 fe ff eb c3 0f 0b e9 7c ff ff ff 0f 0b eb ce <0f> 0b 5b 5d 41 5c 41 5d 41 5e 41 5f c3 90 0f 1f 44 00 00 41 57 41 [224913.935932] RSP: 0018:ffff88816271fd38 EFLAGS: 00010206 [224913.935941] RAX: 0000000000000ae8 RBX: ffff88815acd5240 RCX: dffffc0000000000 [224913.935948] RDX: 0000000000000003 RSI: 0000000000000ae8 RDI: ffff88815acd5460 [224913.935954] RBP: ffff88815acd5460 R08: ffffffff955c0ae8 R09: fffffbfff2e6f543 [224913.935961] R10: ffffffff9737aa17 R11: fffffbfff2e6f542 R12: ffff88815acd5390 [224913.935967] R13: ffff88815acd5480 R14: ffffffff98d0c080 R15: ffffffff96267500 [224913.935974] FS: 00007f86e6bd1700(0000) GS:ffff888451cc0000(0000) knlGS:0000000000000000 [224913.935981] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [224913.935988] CR2: 000000c0008eb000 CR3: 00000001020e0005 CR4: 00000000003706e0 [224913.935994] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [224913.936000] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [224913.936007] Call Trace: [224913.936016] inet_csk_destroy_sock+0xba/0x1f0 [224913.936033] __tcp_close+0x620/0x790 [224913.936047] tcp_close+0x20/0x80 [224913.936056] inet_release+0x8f/0xf0 [224913.936070] __sock_release+0x72/0x120 [224913.936083] sock_close+0x14/0x20 Fixes: a136678c0bdbb ("bpf: sk_msg, zap ingress queue on psock down") Signed-off-by: John Fastabend <john.fastabend@gmail.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Acked-by: Jakub Sitnicki <jakub@cloudflare.com> Acked-by: Martin KaFai Lau <kafai@fb.com> Link: https://lore.kernel.org/bpf/20210727160500.1713554-3-john.fastabend@gmail.com
* bpf, sockmap: Zap ingress queues after stopping strparserJohn Fastabend2021-07-271-2/+2
| | | | | | | | | | | | | | | | | We don't want strparser to run and pass skbs into skmsg handlers when the psock is null. We just sk_drop them in this case. When removing a live socket from map it means extra drops that we do not need to incur. Move the zap below strparser close to avoid this condition. This way we stop the stream parser first stopping it from processing packets and then delete the psock. Fixes: a136678c0bdbb ("bpf: sk_msg, zap ingress queue on psock down") Signed-off-by: John Fastabend <john.fastabend@gmail.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Acked-by: Jakub Sitnicki <jakub@cloudflare.com> Acked-by: Martin KaFai Lau <kafai@fb.com> Link: https://lore.kernel.org/bpf/20210727160500.1713554-2-john.fastabend@gmail.com
* bpf, sockmap: Fix potential memory leak on unlikely error caseJohn Fastabend2021-07-151-5/+11
| | | | | | | | | | | | If skb_linearize is needed and fails we could leak a msg on the error handling. To fix ensure we kfree the msg block before returning error. Found during code review. Fixes: 4363023d2668e ("bpf, sockmap: Avoid failures from skb_to_sgvec when skb has frag_list") Signed-off-by: John Fastabend <john.fastabend@gmail.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Reviewed-by: Cong Wang <cong.wang@bytedance.com> Link: https://lore.kernel.org/bpf/20210712195546.423990-2-john.fastabend@gmail.com
* skmsg: Increase sk->sk_drops when dropping packetsCong Wang2021-06-211-8/+14
| | | | | | | | | | | | | | It is hard to observe packet drops without increasing relevant drop counters, here we should increase sk->sk_drops which is a protocol-independent counter. Fortunately psock is always associated with a struct sock, we can just use psock->sk. Suggested-by: John Fastabend <john.fastabend@gmail.com> Signed-off-by: Cong Wang <cong.wang@bytedance.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: John Fastabend <john.fastabend@gmail.com> Acked-by: Jakub Sitnicki <jakub@cloudflare.com> Link: https://lore.kernel.org/bpf/20210615021342.7416-9-xiyou.wangcong@gmail.com
* skmsg: Pass source psock to sk_psock_skb_redirect()Cong Wang2021-06-211-5/+6
| | | | | | | | | | | | | sk_psock_skb_redirect() only takes skb as a parameter, we will need to know where this skb is from, so just pass the source psock to this function as a new parameter. This patch prepares for the next one. Signed-off-by: Cong Wang <cong.wang@bytedance.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: John Fastabend <john.fastabend@gmail.com> Acked-by: Jakub Sitnicki <jakub@cloudflare.com> Link: https://lore.kernel.org/bpf/20210615021342.7416-8-xiyou.wangcong@gmail.com
* skmsg: Teach sk_psock_verdict_apply() to return errorsCong Wang2021-06-211-9/+14
| | | | | | | | | | | | | | | | Currently sk_psock_verdict_apply() is void, but it handles some error conditions too. Its caller is impossible to learn whether it succeeds or fails, especially sk_psock_verdict_recv(). Make it return int to indicate error cases and propagate errors to callers properly. Fixes: ef5659280eb1 ("bpf, sockmap: Allow skipping sk_skb parser program") Signed-off-by: Cong Wang <cong.wang@bytedance.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: John Fastabend <john.fastabend@gmail.com> Acked-by: Jakub Sitnicki <jakub@cloudflare.com> Link: https://lore.kernel.org/bpf/20210615021342.7416-7-xiyou.wangcong@gmail.com
* skmsg: Fix a memory leak in sk_psock_verdict_apply()Cong Wang2021-06-211-0/+5
| | | | | | | | | | | | | | If the dest psock does not set SK_PSOCK_TX_ENABLED, the skb can't be queued anywhere so must be dropped. This one is found during code review. Fixes: 799aa7f98d53 ("skmsg: Avoid lock_sock() in sk_psock_backlog()") Signed-off-by: Cong Wang <cong.wang@bytedance.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: John Fastabend <john.fastabend@gmail.com> Acked-by: Jakub Sitnicki <jakub@cloudflare.com> Link: https://lore.kernel.org/bpf/20210615021342.7416-6-xiyou.wangcong@gmail.com
* skmsg: Clear skb redirect pointer before dropping itCong Wang2021-06-211-0/+2
| | | | | | | | | | | | | | | When we drop skb inside sk_psock_skb_redirect(), we have to clear its skb->_sk_redir pointer too, otherwise kfree_skb() would misinterpret it as a valid skb->_skb_refdst and dst_release() would eventually complain. Fixes: e3526bb92a20 ("skmsg: Move sk_redir from TCP_SKB_CB to skb") Reported-by: Jiang Wang <jiang.wang@bytedance.com> Signed-off-by: Cong Wang <cong.wang@bytedance.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: John Fastabend <john.fastabend@gmail.com> Acked-by: Jakub Sitnicki <jakub@cloudflare.com> Link: https://lore.kernel.org/bpf/20210615021342.7416-5-xiyou.wangcong@gmail.com
* skmsg: Improve udp_bpf_recvmsg() accuracyCong Wang2021-06-211-23/+0
| | | | | | | | | | | | | | | | | | | | | | I tried to reuse sk_msg_wait_data() for different protocols, but it turns out it can not be simply reused. For example, UDP actually uses two queues to receive skb: udp_sk(sk)->reader_queue and sk->sk_receive_queue. So we have to check both of them to know whether we have received any packet. Also, UDP does not lock the sock during BH Rx path, it makes no sense for its ->recvmsg() to lock the sock. It is always possible for ->recvmsg() to be called before packets actually arrive in the receive queue, we just use best effort to make it accurate here. Fixes: 1f5be6b3b063 ("udp: Implement udp_bpf_recvmsg() for sockmap") Signed-off-by: Cong Wang <cong.wang@bytedance.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: John Fastabend <john.fastabend@gmail.com> Acked-by: Jakub Sitnicki <jakub@cloudflare.com> Link: https://lore.kernel.org/bpf/20210615021342.7416-2-xiyou.wangcong@gmail.com
* Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netJakub Kicinski2021-04-091-7/+5
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Conflicts: MAINTAINERS - keep Chandrasekar drivers/net/ethernet/mellanox/mlx5/core/en_main.c - simple fix + trust the code re-added to param.c in -next is fine include/linux/bpf.h - trivial include/linux/ethtool.h - trivial, fix kdoc while at it include/linux/skmsg.h - move to relevant place in tcp.c, comment re-wrapped net/core/skmsg.c - add the sk = sk // sk = NULL around calls net/tipc/crypto.c - trivial Signed-off-by: Jakub Kicinski <kuba@kernel.org>
| * bpf, sockmap: Fix incorrect fwd_alloc accountingJohn Fastabend2021-04-071-7/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Incorrect accounting fwd_alloc can result in a warning when the socket is torn down, [18455.319240] WARNING: CPU: 0 PID: 24075 at net/core/stream.c:208 sk_stream_kill_queues+0x21f/0x230 [...] [18455.319543] Call Trace: [18455.319556] inet_csk_destroy_sock+0xba/0x1f0 [18455.319577] tcp_rcv_state_process+0x1b4e/0x2380 [18455.319593] ? lock_downgrade+0x3a0/0x3a0 [18455.319617] ? tcp_finish_connect+0x1e0/0x1e0 [18455.319631] ? sk_reset_timer+0x15/0x70 [18455.319646] ? tcp_schedule_loss_probe+0x1b2/0x240 [18455.319663] ? lock_release+0xb2/0x3f0 [18455.319676] ? __release_sock+0x8a/0x1b0 [18455.319690] ? lock_downgrade+0x3a0/0x3a0 [18455.319704] ? lock_release+0x3f0/0x3f0 [18455.319717] ? __tcp_close+0x2c6/0x790 [18455.319736] ? tcp_v4_do_rcv+0x168/0x370 [18455.319750] tcp_v4_do_rcv+0x168/0x370 [18455.319767] __release_sock+0xbc/0x1b0 [18455.319785] __tcp_close+0x2ee/0x790 [18455.319805] tcp_close+0x20/0x80 This currently happens because on redirect case we do skb_set_owner_r() with the original sock. This increments the fwd_alloc memory accounting on the original sock. Then on redirect we may push this into the queue of the psock we are redirecting to. When the skb is flushed from the queue we give the memory back to the original sock. The problem is if the original sock is destroyed/closed with skbs on another psocks queue then the original sock will not have a way to reclaim the memory before being destroyed. Then above warning will be thrown sockA sockB sk_psock_strp_read() sk_psock_verdict_apply() -- SK_REDIRECT -- sk_psock_skb_redirect() skb_queue_tail(psock_other->ingress_skb..) sk_close() sock_map_unref() sk_psock_put() sk_psock_drop() sk_psock_zap_ingress() At this point we have torn down our own psock, but have the outstanding skb in psock_other. Note that SK_PASS doesn't have this problem because the sk_psock_drop() logic releases the skb, its still associated with our psock. To resolve lets only account for sockets on the ingress queue that are still associated with the current socket. On the redirect case we will check memory limits per 6fa9201a89898, but will omit fwd_alloc accounting until skb is actually enqueued. When the skb is sent via skb_send_sock_locked or received with sk_psock_skb_ingress memory will be claimed on psock_other. Fixes: 6fa9201a89898 ("bpf, sockmap: Avoid returning unneeded EAGAIN when redirecting to self") Reported-by: Andrii Nakryiko <andrii@kernel.org> Signed-off-by: John Fastabend <john.fastabend@gmail.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Link: https://lore.kernel.org/bpf/161731444013.68884.4021114312848535993.stgit@john-XPS-13-9370
* | skmsg: Extract __tcp_bpf_recvmsg() and tcp_bpf_wait_data()Cong Wang2021-04-011-0/+98
| | | | | | | | | | | | | | | | | | | | | | | | | | Although these two functions are only used by TCP, they are not specific to TCP at all, both operate on skmsg and ingress_msg, so fit in net/core/skmsg.c very well. And we will need them for non-TCP, so rename and move them to skmsg.c and export them to modules. Signed-off-by: Cong Wang <cong.wang@bytedance.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/20210331023237.41094-13-xiyou.wangcong@gmail.com
* | sock: Introduce sk->sk_prot->psock_update_sk_prot()Cong Wang2021-04-011-5/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently sockmap calls into each protocol to update the struct proto and replace it. This certainly won't work when the protocol is implemented as a module, for example, AF_UNIX. Introduce a new ops sk->sk_prot->psock_update_sk_prot(), so each protocol can implement its own way to replace the struct proto. This also helps get rid of symbol dependencies on CONFIG_INET. Signed-off-by: Cong Wang <cong.wang@bytedance.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/20210331023237.41094-11-xiyou.wangcong@gmail.com
* | sock_map: Introduce BPF_SK_SKB_VERDICTCong Wang2021-04-011-1/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | Reusing BPF_SK_SKB_STREAM_VERDICT is possible but its name is confusing and more importantly we still want to distinguish them from user-space. So we can just reuse the stream verdict code but introduce a new type of eBPF program, skb_verdict. Users are not allowed to attach stream_verdict and skb_verdict programs to the same map. Signed-off-by: Cong Wang <cong.wang@bytedance.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: John Fastabend <john.fastabend@gmail.com> Link: https://lore.kernel.org/bpf/20210331023237.41094-10-xiyou.wangcong@gmail.com
* | skmsg: Use GFP_KERNEL in sk_psock_create_ingress_msg()Cong Wang2021-04-011-1/+1
| | | | | | | | | | | | | | | | | | This function is only called in process context. Signed-off-by: Cong Wang <cong.wang@bytedance.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: John Fastabend <john.fastabend@gmail.com> Link: https://lore.kernel.org/bpf/20210331023237.41094-7-xiyou.wangcong@gmail.com
* | skmsg: Use rcu work for destroying psockCong Wang2021-04-011-12/+5
| | | | | | | | | | | | | | | | | | | | The RCU callback sk_psock_destroy() only queues work psock->gc, so we can just switch to rcu work to simplify the code. Signed-off-by: Cong Wang <cong.wang@bytedance.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: John Fastabend <john.fastabend@gmail.com> Link: https://lore.kernel.org/bpf/20210331023237.41094-6-xiyou.wangcong@gmail.com
* | skmsg: Avoid lock_sock() in sk_psock_backlog()Cong Wang2021-04-011-16/+34
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We do not have to lock the sock to avoid losing sk_socket, instead we can purge all the ingress queues when we close the socket. Sending or receiving packets after orphaning socket makes no sense. We do purge these queues when psock refcnt reaches zero but here we want to purge them explicitly in sock_map_close(). There are also some nasty race conditions on testing bit SK_PSOCK_TX_ENABLED and queuing/canceling the psock work, we can expand psock->ingress_lock a bit to protect them too. As noticed by John, we still have to lock the psock->work, because the same work item could be running concurrently on different CPU's. Signed-off-by: Cong Wang <cong.wang@bytedance.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: John Fastabend <john.fastabend@gmail.com> Link: https://lore.kernel.org/bpf/20210331023237.41094-5-xiyou.wangcong@gmail.com
* | skmsg: Introduce a spinlock to protect ingress_msgCong Wang2021-04-011-0/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently we rely on lock_sock to protect ingress_msg, it is too big for this, we can actually just use a spinlock to protect this list like protecting other skb queues. __tcp_bpf_recvmsg() is still special because of peeking, it still has to use lock_sock. Signed-off-by: Cong Wang <cong.wang@bytedance.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Jakub Sitnicki <jakub@cloudflare.com> Acked-by: John Fastabend <john.fastabend@gmail.com> Link: https://lore.kernel.org/bpf/20210331023237.41094-3-xiyou.wangcong@gmail.com
* | skmsg: Lock ingress_skb when purgingCong Wang2021-04-011-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | Currently we purge the ingress_skb queue only when psock refcnt goes down to 0, so locking the queue is not necessary, but in order to be called during ->close, we have to lock it here. Signed-off-by: Cong Wang <cong.wang@bytedance.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Jakub Sitnicki <jakub@cloudflare.com> Acked-by: John Fastabend <john.fastabend@gmail.com> Link: https://lore.kernel.org/bpf/20210331023237.41094-2-xiyou.wangcong@gmail.com
* | skmsg: Get rid of sk_psock_bpf_run()Cong Wang2021-02-261-10/+4
| | | | | | | | | | | | | | | | | | | | | | It is now nearly identical to bpf_prog_run_pin_on_cpu() and it has an unused parameter 'psock', so we can just get rid of it and call bpf_prog_run_pin_on_cpu() directly. Signed-off-by: Cong Wang <cong.wang@bytedance.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Jakub Sitnicki <jakub@cloudflare.com> Link: https://lore.kernel.org/bpf/20210223184934.6054-9-xiyou.wangcong@gmail.com
* | skmsg: Make __sk_psock_purge_ingress_msg() staticCong Wang2021-02-261-1/+1
| | | | | | | | | | | | | | | | | | It is only used within skmsg.c so can become static. Signed-off-by: Cong Wang <cong.wang@bytedance.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Jakub Sitnicki <jakub@cloudflare.com> Link: https://lore.kernel.org/bpf/20210223184934.6054-8-xiyou.wangcong@gmail.com
* | sock_map: Rename skb_parser and skb_verdictCong Wang2021-02-261-7/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | These two eBPF programs are tied to BPF_SK_SKB_STREAM_PARSER and BPF_SK_SKB_STREAM_VERDICT, rename them to reflect the fact they are only used for TCP. And save the name 'skb_verdict' for general use later. Signed-off-by: Cong Wang <cong.wang@bytedance.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Reviewed-by: Lorenz Bauer <lmb@cloudflare.com> Acked-by: John Fastabend <john.fastabend@gmail.com> Acked-by: Jakub Sitnicki <jakub@cloudflare.com> Link: https://lore.kernel.org/bpf/20210223184934.6054-6-xiyou.wangcong@gmail.com
* | skmsg: Move sk_redir from TCP_SKB_CB to skbCong Wang2021-02-261-12/+19
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently TCP_SKB_CB() is hard-coded in skmsg code, it certainly does not work for any other non-TCP protocols. We can move them to skb ext, but it introduces a memory allocation on fast path. Fortunately, we only need to a word-size to store all the information, because the flags actually only contains 1 bit so can be just packed into the lowest bit of the "pointer", which is stored as unsigned long. Inside struct sk_buff, '_skb_refdst' can be reused because skb dst is no longer needed after ->sk_data_ready() so we can just drop it. Signed-off-by: Cong Wang <cong.wang@bytedance.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: John Fastabend <john.fastabend@gmail.com> Acked-by: Jakub Sitnicki <jakub@cloudflare.com> Link: https://lore.kernel.org/bpf/20210223184934.6054-5-xiyou.wangcong@gmail.com
* | bpf: Compute data_end dynamically with JIT codeCong Wang2021-02-261-1/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently, we compute ->data_end with a compile-time constant offset of skb. But as Jakub pointed out, we can actually compute it in eBPF JIT code at run-time, so that we can competely get rid of ->data_end. This is similar to skb_shinfo(skb) computation in bpf_convert_shinfo_access(). Suggested-by: Jakub Sitnicki <jakub@cloudflare.com> Signed-off-by: Cong Wang <cong.wang@bytedance.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: John Fastabend <john.fastabend@gmail.com> Acked-by: Jakub Sitnicki <jakub@cloudflare.com> Link: https://lore.kernel.org/bpf/20210223184934.6054-4-xiyou.wangcong@gmail.com
* | skmsg: Get rid of struct sk_psock_parserCong Wang2021-02-261-37/+16
| | | | | | | | | | | | | | | | | | | | | | | | | | struct sk_psock_parser is embedded in sk_psock, it is unnecessary as skb verdict also uses ->saved_data_ready. We can simply fold these fields into sk_psock, and get rid of ->enabled. Signed-off-by: Cong Wang <cong.wang@bytedance.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: John Fastabend <john.fastabend@gmail.com> Acked-by: Jakub Sitnicki <jakub@cloudflare.com> Link: https://lore.kernel.org/bpf/20210223184934.6054-3-xiyou.wangcong@gmail.com
* | bpf: Clean up sockmap related KconfigsCong Wang2021-02-261-66/+79
|/ | | | | | | | | | | | | | | | | | | As suggested by John, clean up sockmap related Kconfigs: Reduce the scope of CONFIG_BPF_STREAM_PARSER down to TCP stream parser, to reflect its name. Make the rest sockmap code simply depend on CONFIG_BPF_SYSCALL and CONFIG_INET, the latter is still needed at this point because of TCP/UDP proto update. And leave CONFIG_NET_SOCK_MSG untouched, as it is used by non-sockmap cases. Signed-off-by: Cong Wang <cong.wang@bytedance.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Reviewed-by: Lorenz Bauer <lmb@cloudflare.com> Acked-by: John Fastabend <john.fastabend@gmail.com> Acked-by: Jakub Sitnicki <jakub@cloudflare.com> Link: https://lore.kernel.org/bpf/20210223184934.6054-2-xiyou.wangcong@gmail.com
* skmsg: Make sk_psock_destroy() staticCong Wang2021-01-281-2/+1
| | | | | | | | | | | | sk_psock_destroy() is a RCU callback, I can't see any reason why it could be used outside. Signed-off-by: Cong Wang <cong.wang@bytedance.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Cc: John Fastabend <john.fastabend@gmail.com> Cc: Jakub Sitnicki <jakub@cloudflare.com> Cc: Lorenz Bauer <lmb@cloudflare.com> Link: https://lore.kernel.org/bpf/20210127221501.46866-1-xiyou.wangcong@gmail.com
* bpf, sockmap: Avoid failures from skb_to_sgvec when skb has frag_listJohn Fastabend2020-11-181-2/+9
| | | | | | | | | | | | | | | | | | | | | When skb has a frag_list its possible for skb_to_sgvec() to fail. This happens when the scatterlist has fewer elements to store pages than would be needed for the initial skb plus any of its frags. This case appears rare, but is possible when running an RX parser/verdict programs exposed to the internet. Currently, when this happens we throw an error, break the pipe, and kfree the msg. This effectively breaks the application or forces it to do a retry. Lets catch this case and handle it by doing an skb_linearize() on any skb we receive with frags. At this point skb_to_sgvec should not fail because the failing conditions would require frags to be in place. Fixes: 604326b41a6fb ("bpf, sockmap: convert to generic sk_msg interface") 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/160556576837.73229.14800682790808797635.stgit@john-XPS-13-9370
* bpf, sockmap: Handle memory acct if skb_verdict prog redirects to selfJohn Fastabend2020-11-181-0/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | If the skb_verdict_prog redirects an skb knowingly to itself, fix your BPF program this is not optimal and an abuse of the API please use SK_PASS. That said there may be cases, such as socket load balancing, where picking the socket is hashed based or otherwise picks the same socket it was received on in some rare cases. If this happens we don't want to confuse userspace giving them an EAGAIN error if we can avoid it. To avoid double accounting in these cases. At the moment even if the skb has already been charged against the sockets rcvbuf and forward alloc we check it again and do set_owner_r() causing it to be orphaned and recharged. For one this is useless work, but more importantly we can have a case where the skb could be put on the ingress queue, but because we are under memory pressure we return EAGAIN. The trouble here is the skb has already been accounted for so any rcvbuf checks include the memory associated with the packet already. This rolls up and can result in unnecessary EAGAIN errors in userspace read() calls. Fix by doing an unlikely check and skipping checks if skb->sk == sk. Fixes: 51199405f9672 ("bpf: skb_verdict, support SK_PASS on RX BPF path") 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/160556574804.73229.11328201020039674147.stgit@john-XPS-13-9370
* bpf, sockmap: Avoid returning unneeded EAGAIN when redirecting to selfJohn Fastabend2020-11-181-19/+53
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If a socket redirects to itself and it is under memory pressure it is possible to get a socket stuck so that recv() returns EAGAIN and the socket can not advance for some time. This happens because when redirecting a skb to the same socket we received the skb on we first check if it is OK to enqueue the skb on the receiving socket by checking memory limits. But, if the skb is itself the object holding the memory needed to enqueue the skb we will keep retrying from kernel side and always fail with EAGAIN. Then userspace will get a recv() EAGAIN error if there are no skbs in the psock ingress queue. This will continue until either some skbs get kfree'd causing the memory pressure to reduce far enough that we can enqueue the pending packet or the socket is destroyed. In some cases its possible to get a socket stuck for a noticeable amount of time if the socket is only receiving skbs from sk_skb verdict programs. To reproduce I make the socket memory limits ridiculously low so sockets are always under memory pressure. More often though if under memory pressure it looks like a spurious EAGAIN error on user space side causing userspace to retry and typically enough has moved on the memory side that it works. To fix skip memory checks and skb_orphan if receiving on the same sock as already assigned. For SK_PASS cases this is easy, its always the same socket so we can just omit the orphan/set_owner pair. For backlog cases we need to check skb->sk and decide if the orphan and set_owner pair are needed. Fixes: 51199405f9672 ("bpf: skb_verdict, support SK_PASS on RX BPF path") 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/160556572660.73229.12566203819812939627.stgit@john-XPS-13-9370
* bpf, sockmap: Use truesize with sk_rmem_schedule()John Fastabend2020-11-181-1/+1
| | | | | | | | | | | We use skb->size with sk_rmem_scheduled() which is not correct. Instead use truesize to align with socket and tcp stack usage of sk_rmem_schedule. Suggested-by: Daniel Borkman <daniel@iogearbox.net> 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/160556570616.73229.17003722112077507863.stgit@john-XPS-13-9370
* bpf, sockmap: Ensure SO_RCVBUF memory is observed on ingress redirectJohn Fastabend2020-11-181-4/+16
| | | | | | | | | | | | | | | Fix sockmap sk_skb programs so that they observe sk_rcvbuf limits. This allows users to tune SO_RCVBUF and sockmap will honor them. We can refactor the if(charge) case out in later patches. But, keep this fix to the point. Fixes: 51199405f9672 ("bpf: skb_verdict, support SK_PASS on RX BPF path") Suggested-by: Jakub Sitnicki <jakub@cloudflare.com> 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/160556568657.73229.8404601585878439060.stgit@john-XPS-13-9370
* bpf, sockmap: Allow skipping sk_skb parser programJohn Fastabend2020-10-111-0/+78
| | | | | | | | | | | | | | | | Currently, we often run with a nop parser namely one that just does this, 'return skb->len'. This happens when either our verdict program can handle streaming data or it is only looking at socket data such as IP addresses and other metadata associated with the flow. The second case is common for a L3/L4 proxy for instance. So lets allow loading programs without the parser then we can skip the stream parser logic and avoid having to add a BPF program that is effectively a nop. Signed-off-by: John Fastabend <john.fastabend@gmail.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/160239297866.8495.13345662302749219672.stgit@john-Precision-5820-Tower
* bpf, sockmap: Add memory accounting so skbs on ingress lists are visibleJohn Fastabend2020-10-111-16/+15
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Move skb->sk assignment out of sk_psock_bpf_run() and into individual callers. Then we can use proper skb_set_owner_r() call to assign a sk to a skb. This improves things by also charging the truesize against the sockets sk_rmem_alloc counter. With this done we get some accounting in place to ensure the memory associated with skbs on the workqueue are still being accounted for somewhere. Finally, by using skb_set_owner_r the destructor is setup so we can just let the normal skb_kfree logic recover the memory. Combined with previous patch dropping skb_orphan() we now can recover from memory pressure and maintain accounting. Note, we will charge the skbs against their originating socket even if being redirected into another socket. Once the skb completes the redirect op the kfree_skb will give the memory back. This is important because if we charged the socket we are redirecting to (like it was done before this series) the sock_writeable() test could fail because of the skb trying to be sent is already charged against the socket. Also TLS case is special. Here we wait until we have decided not to simply PASS the packet up the stack. In the case where we PASS the packet up the stack we already have an skb which is accounted for on the TLS socket context. For the parser case we continue to just set/clear skb->sk this is because the skb being used here may be combined with other skbs or turned into multiple skbs depending on the parser logic. For example the parser could request a payload length greater than skb->len so that the strparser needs to collect multiple skbs. At any rate the final result will be handled in the strparser recv callback. Fixes: 604326b41a6fb ("bpf, sockmap: convert to generic sk_msg interface") Signed-off-by: John Fastabend <john.fastabend@gmail.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/160226867513.5692.10579573214635925960.stgit@john-Precision-5820-Tower
* bpf, sockmap: Remove skb_orphan and let normal skb_kfree do cleanupJohn Fastabend2020-10-111-7/+7
| | | | | | | | | | | | | | | | | Calling skb_orphan() is unnecessary in the strp rcv handler because the skb is from a skb_clone() in __strp_recv. So it never has a destructor or a sk assigned. Plus its confusing to read because it might hint to the reader that the skb could have an sk assigned which is not true. Even if we did have an sk assigned it would be cleaner to simply wait for the upcoming kfree_skb(). Additionally, move the comment about strparser clone up so its closer to the logic it is describing and add to it so that it is more complete. Fixes: 604326b41a6fb ("bpf, sockmap: convert to generic sk_msg interface") Signed-off-by: John Fastabend <john.fastabend@gmail.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/160226865548.5692.9098315689984599579.stgit@john-Precision-5820-Tower
* bpf, sockmap: Remove dropped data on errors in redirect caseJohn Fastabend2020-10-111-14/+14
| | | | | | | | | | | | | | | | | | In the sk_skb redirect case we didn't handle the case where we overrun the sk_rmem_alloc entry on ingress redirect or sk_wmem_alloc on egress. Because we didn't have anything implemented we simply dropped the skb. This meant data could be dropped if socket memory accounting was in place. This fixes the above dropped data case by moving the memory checks later in the code where we actually do the send or recv. This pushes those checks into the workqueue and allows us to return an EAGAIN error which in turn allows us to try again later from the workqueue. Fixes: 51199405f9672 ("bpf: skb_verdict, support SK_PASS on RX BPF path") Signed-off-by: John Fastabend <john.fastabend@gmail.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/160226863689.5692.13861422742592309285.stgit@john-Precision-5820-Tower
* bpf, sockmap: Remove skb_set_owner_w wmem will be taken later from sendpageJohn Fastabend2020-10-111-2/+0
| | | | | | | | | | | | | | | | | | | | | | The skb_set_owner_w is unnecessary here. The sendpage call will create a fresh skb and set the owner correctly from workqueue. Its also not entirely harmless because it consumes cycles, but also impacts resource accounting by increasing sk_wmem_alloc. This is charging the socket we are going to send to for the skb, but we will put it on the workqueue for some time before this happens so we are artifically inflating sk_wmem_alloc for this period. Further, we don't know how many skbs will be used to send the packet or how it will be broken up when sent over the new socket so charging it with one big sum is also not correct when the workqueue may break it up if facing memory pressure. Seeing we don't know how/when this is going to be sent drop the early accounting. A later patch will do proper accounting charged on receive socket for the case where skbs get enqueued on the workqueue. Fixes: 604326b41a6fb ("bpf, sockmap: convert to generic sk_msg interface") Signed-off-by: John Fastabend <john.fastabend@gmail.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/160226861708.5692.17964237936462425136.stgit@john-Precision-5820-Tower
* bpf, sockmap: On receive programs try to fast track SK_PASS ingressJohn Fastabend2020-10-111-2/+15
| | | | | | | | | | | | | | | | | | | | | | | When we receive an skb and the ingress skb verdict program returns SK_PASS we currently set the ingress flag and put it on the workqueue so it can be turned into a sk_msg and put on the sk_msg ingress queue. Then finally telling userspace with data_ready hook. Here we observe that if the workqueue is empty then we can try to convert into a sk_msg type and call data_ready directly without bouncing through a workqueue. Its a common pattern to have a recv verdict program for visibility that always returns SK_PASS. In this case unless there is an ENOMEM error or we overrun the socket we can avoid the workqueue completely only using it when we fall back to error cases caused by memory pressure. By doing this we eliminate another case where data may be dropped if errors occur on memory limits in workqueue. Fixes: 51199405f9672 ("bpf: skb_verdict, support SK_PASS on RX BPF path") Signed-off-by: John Fastabend <john.fastabend@gmail.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/160226859704.5692.12929678876744977669.stgit@john-Precision-5820-Tower
* bpf, sockmap: Skb verdict SK_PASS to self already checked rmem limitsJohn Fastabend2020-10-111-9/+6
| | | | | | | | | | | | | | | | | | For sk_skb case where skb_verdict program returns SK_PASS to continue to pass packet up the stack, the memory limits were already checked before enqueuing in skb_queue_tail from TCP side. So, lets remove the extra checks here. The theory is if the TCP stack believes we have memory to receive the packet then lets trust the stack and not double check the limits. In fact the accounting here can cause a drop if sk_rmem_alloc has increased after the stack accepted this packet, but before the duplicate check here. And worse if this happens because TCP stack already believes the data has been received there is no retransmit. Fixes: 51199405f9672 ("bpf: skb_verdict, support SK_PASS on RX BPF path") Signed-off-by: John Fastabend <john.fastabend@gmail.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/160226857664.5692.668205469388498375.stgit@john-Precision-5820-Tower
* Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netJakub Kicinski2020-09-041-1/+0
|\ | | | | | | | | | | | | | | | | | | | | | | We got slightly different patches removing a double word in a comment in net/ipv4/raw.c - picked the version from net. Simple conflict in drivers/net/ethernet/ibm/ibmvnic.c. Use cached values instead of VNIC login response buffer (following what commit 507ebe6444a4 ("ibmvnic: Fix use-after-free of VNIC login response buffer") did). Signed-off-by: Jakub Kicinski <kuba@kernel.org>
| * treewide: Use fallthrough pseudo-keywordGustavo A. R. Silva2020-08-231-1/+0
| | | | | | | | | | | | | | | | | | | | Replace the existing /* fall through */ comments and its variants with the new pseudo-keyword macro fallthrough[1]. Also, remove unnecessary fall-through markings when it is the case. [1] https://www.kernel.org/doc/html/v5.7/process/deprecated.html?highlight=fallthrough#implicit-switch-case-fall-through Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>