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2019-08-04rxrpc: Fix send on a connected, but unbound socketDavid Howells1-2/+2
[ Upstream commit e835ada07091f40dcfb1bc735082bd0a7c005e59 ] If sendmsg() or sendmmsg() is called on a connected socket that hasn't had bind() called on it, then an oops will occur when the kernel tries to connect the call because no local endpoint has been allocated. Fix this by implicitly binding the socket if it is in the RXRPC_CLIENT_UNBOUND state, just like it does for the RXRPC_UNBOUND state. Further, the state should be transitioned to RXRPC_CLIENT_BOUND after this to prevent further attempts to bind it. This can be tested with: #include <stdio.h> #include <stdlib.h> #include <string.h> #include <sys/socket.h> #include <arpa/inet.h> #include <linux/rxrpc.h> static const unsigned char inet6_addr[16] = { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, -1, -1, 0xac, 0x14, 0x14, 0xaa }; int main(void) { struct sockaddr_rxrpc srx; struct cmsghdr *cm; struct msghdr msg; unsigned char control[16]; int fd; memset(&srx, 0, sizeof(srx)); srx.srx_family = 0x21; srx.srx_service = 0; srx.transport_type = AF_INET; srx.transport_len = 0x1c; srx.transport.sin6.sin6_family = AF_INET6; srx.transport.sin6.sin6_port = htons(0x4e22); srx.transport.sin6.sin6_flowinfo = htons(0x4e22); srx.transport.sin6.sin6_scope_id = htons(0xaa3b); memcpy(&srx.transport.sin6.sin6_addr, inet6_addr, 16); cm = (struct cmsghdr *)control; cm->cmsg_len = CMSG_LEN(sizeof(unsigned long)); cm->cmsg_level = SOL_RXRPC; cm->cmsg_type = RXRPC_USER_CALL_ID; *(unsigned long *)CMSG_DATA(cm) = 0; msg.msg_name = NULL; msg.msg_namelen = 0; msg.msg_iov = NULL; msg.msg_iovlen = 0; msg.msg_control = control; msg.msg_controllen = cm->cmsg_len; msg.msg_flags = 0; fd = socket(AF_RXRPC, SOCK_DGRAM, AF_INET); connect(fd, (struct sockaddr *)&srx, sizeof(srx)); sendmsg(fd, &msg, 0); return 0; } Leading to the following oops: BUG: kernel NULL pointer dereference, address: 0000000000000018 #PF: supervisor read access in kernel mode #PF: error_code(0x0000) - not-present page ... RIP: 0010:rxrpc_connect_call+0x42/0xa01 ... Call Trace: ? mark_held_locks+0x47/0x59 ? __local_bh_enable_ip+0xb6/0xba rxrpc_new_client_call+0x3b1/0x762 ? rxrpc_do_sendmsg+0x3c0/0x92e rxrpc_do_sendmsg+0x3c0/0x92e rxrpc_sendmsg+0x16b/0x1b5 sock_sendmsg+0x2d/0x39 ___sys_sendmsg+0x1a4/0x22a ? release_sock+0x19/0x9e ? reacquire_held_locks+0x136/0x160 ? release_sock+0x19/0x9e ? find_held_lock+0x2b/0x6e ? __lock_acquire+0x268/0xf73 ? rxrpc_connect+0xdd/0xe4 ? __local_bh_enable_ip+0xb6/0xba __sys_sendmsg+0x5e/0x94 do_syscall_64+0x7d/0x1bf entry_SYSCALL_64_after_hwframe+0x49/0xbe Fixes: 2341e0775747 ("rxrpc: Simplify connect() implementation and simplify sendmsg() op") Reported-by: syzbot+7966f2a0b2c7da8939b4@syzkaller.appspotmail.com Signed-off-by: David Howells <dhowells@redhat.com> Reviewed-by: Marc Dionne <marc.dionne@auristor.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-03-19rxrpc: Fix client call queueing, waiting for channelDavid Howells1-2/+2
[ Upstream commit 69ffaebb90369ce08657b5aea4896777b9d6e8fc ] rxrpc_get_client_conn() adds a new call to the front of the waiting_calls queue if the connection it's going to use already exists. This is bad as it allows calls to get starved out. Fix this by adding to the tail instead. Also change the other enqueue point in the same function to put it on the front (ie. when we have a new connection). This makes the point that in the case of a new connection the new call goes at the front (though it doesn't actually matter since the queue should be unoccupied). Fixes: 45025bceef17 ("rxrpc: Improve management and caching of client connection objects") Signed-off-by: David Howells <dhowells@redhat.com> Reviewed-by: Marc Dionne <marc.dionne@auristor.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-02-12rxrpc: bad unlock balance in rxrpc_recvmsgEric Dumazet1-1/+2
[ Upstream commit 6dce3c20ac429e7a651d728e375853370c796e8d ] When either "goto wait_interrupted;" or "goto wait_error;" paths are taken, socket lock has already been released. This patch fixes following syzbot splat : WARNING: bad unlock balance detected! 5.0.0-rc4+ #59 Not tainted ------------------------------------- syz-executor223/8256 is trying to release lock (sk_lock-AF_RXRPC) at: [<ffffffff86651353>] rxrpc_recvmsg+0x6d3/0x3099 net/rxrpc/recvmsg.c:598 but there are no more locks to release! other info that might help us debug this: 1 lock held by syz-executor223/8256: #0: 00000000fa9ed0f4 (slock-AF_RXRPC){+...}, at: spin_lock_bh include/linux/spinlock.h:334 [inline] #0: 00000000fa9ed0f4 (slock-AF_RXRPC){+...}, at: release_sock+0x20/0x1c0 net/core/sock.c:2798 stack backtrace: CPU: 1 PID: 8256 Comm: syz-executor223 Not tainted 5.0.0-rc4+ #59 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x172/0x1f0 lib/dump_stack.c:113 print_unlock_imbalance_bug kernel/locking/lockdep.c:3391 [inline] print_unlock_imbalance_bug.cold+0x114/0x123 kernel/locking/lockdep.c:3368 __lock_release kernel/locking/lockdep.c:3601 [inline] lock_release+0x67e/0xa00 kernel/locking/lockdep.c:3860 sock_release_ownership include/net/sock.h:1471 [inline] release_sock+0x183/0x1c0 net/core/sock.c:2808 rxrpc_recvmsg+0x6d3/0x3099 net/rxrpc/recvmsg.c:598 sock_recvmsg_nosec net/socket.c:794 [inline] sock_recvmsg net/socket.c:801 [inline] sock_recvmsg+0xd0/0x110 net/socket.c:797 __sys_recvfrom+0x1ff/0x350 net/socket.c:1845 __do_sys_recvfrom net/socket.c:1863 [inline] __se_sys_recvfrom net/socket.c:1859 [inline] __x64_sys_recvfrom+0xe1/0x1a0 net/socket.c:1859 do_syscall_64+0x103/0x610 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x446379 Code: e8 2c b3 02 00 48 83 c4 18 c3 0f 1f 80 00 00 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 2b 09 fc ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007fe5da89fd98 EFLAGS: 00000246 ORIG_RAX: 000000000000002d RAX: ffffffffffffffda RBX: 00000000006dbc28 RCX: 0000000000446379 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000003 RBP: 00000000006dbc20 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000006dbc2c R13: 0000000000000000 R14: 0000000000000000 R15: 20c49ba5e353f7cf Fixes: 248f219cb8bc ("rxrpc: Rewrite the data and ack handling code") Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: David Howells <dhowells@redhat.com> Reported-by: syzbot <syzkaller@googlegroups.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-11-10rxrpc: Only take the rwind and mtu values from latest ACKDavid Howells1-9/+10
[ Upstream commit 298bc15b2079c324e82d0a6fda39c3d762af7282 ] Move the out-of-order and duplicate ACK packet check to before the call to rxrpc_input_ackinfo() so that the receive window size and MTU size are only checked in the latest ACK packet and don't regress. Fixes: 248f219cb8bc ("rxrpc: Rewrite the data and ack handling code") Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2018-11-10rxrpc: Don't check RXRPC_CALL_TX_LAST after calling rxrpc_rotate_tx_window()David Howells1-16/+19
[ Upstream commit c479d5f2c2e1ce609da08c075054440d97ddff52 ] We should only call the function to end a call's Tx phase if we rotated the marked-last packet out of the transmission buffer. Make rxrpc_rotate_tx_window() return an indication of whether it just rotated the packet marked as the last out of the transmit buffer, carrying the information out of the locked section in that function. We can then check the return value instead of examining RXRPC_CALL_TX_LAST. Fixes: 70790dbe3f66 ("rxrpc: Pass the last Tx packet marker in the annotation buffer") Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2018-05-30rxrpc: Don't treat call aborts as conn abortsDavid Howells1-6/+9
[ Upstream commit 57b0c9d49b94bbeb53649b7fbd264603c1ebd585 ] If a call-level abort is received for the previous call to complete on a connection channel, then that abort is queued for the connection processor to handle. Unfortunately, the connection processor then assumes without checking that the abort is connection-level (ie. callNumber is 0) and distributes it over all active calls on that connection, thereby incorrectly aborting them. Fix this by discarding aborts aimed at a completed call. Further, discard all packets aimed at a call that's complete if there's currently an active call on a channel, since the DATA packets associated with the new call automatically terminate the old call. Fixes: 18bfeba50dfd ("rxrpc: Perform terminal call ACK/ABORT retransmission from conn processor") Reported-by: Marc Dionne <marc.dionne@auristor.com> Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Sasha Levin <alexander.levin@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-05-30rxrpc: Fix Tx ring annotation after initial Tx failureDavid Howells1-1/+3
[ Upstream commit 03877bf6a30cca7d4bc3ffabd3c3e9464a7a1a19 ] rxrpc calls have a ring of packets that are awaiting ACK or retransmission and a parallel ring of annotations that tracks the state of those packets. If the initial transmission of a packet on the underlying UDP socket fails then the packet annotation is marked for resend - but the setting of this mark accidentally erases the last-packet mark also stored in the same annotation slot. If this happens, a call won't switch out of the Tx phase when all the packets have been transmitted. Fix this by retaining the last-packet mark and only altering the packet state. Fixes: 248f219cb8bc ("rxrpc: Rewrite the data and ack handling code") Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Sasha Levin <alexander.levin@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-05-30rxrpc: Work around usercopy checkDavid Howells1-2/+3
[ Upstream commit a16b8d0cf2ec1e626d24bc2a7b9e64ace6f7501d ] Due to a check recently added to copy_to_user(), it's now not permitted to copy from slab-held data to userspace unless the slab is whitelisted. This affects rxrpc_recvmsg() when it attempts to place an RXRPC_USER_CALL_ID control message in the userspace control message buffer. A warning is generated by usercopy_warn() because the source is the copy of the user_call_ID retained in the rxrpc_call struct. Work around the issue by copying the user_call_ID to a variable on the stack and passing that to put_cmsg(). The warning generated looks like: Bad or missing usercopy whitelist? Kernel memory exposure attempt detected from SLUB object 'dmaengine-unmap-128' (offset 680, size 8)! WARNING: CPU: 0 PID: 1401 at mm/usercopy.c:81 usercopy_warn+0x7e/0xa0 ... RIP: 0010:usercopy_warn+0x7e/0xa0 ... Call Trace: __check_object_size+0x9c/0x1a0 put_cmsg+0x98/0x120 rxrpc_recvmsg+0x6fc/0x1010 [rxrpc] ? finish_wait+0x80/0x80 ___sys_recvmsg+0xf8/0x240 ? __clear_rsb+0x25/0x3d ? __clear_rsb+0x15/0x3d ? __clear_rsb+0x25/0x3d ? __clear_rsb+0x15/0x3d ? __clear_rsb+0x25/0x3d ? __clear_rsb+0x15/0x3d ? __clear_rsb+0x25/0x3d ? __clear_rsb+0x15/0x3d ? finish_task_switch+0xa6/0x2b0 ? trace_hardirqs_on_caller+0xed/0x180 ? _raw_spin_unlock_irq+0x29/0x40 ? __sys_recvmsg+0x4e/0x90 __sys_recvmsg+0x4e/0x90 do_syscall_64+0x7a/0x220 entry_SYSCALL_64_after_hwframe+0x26/0x9b Reported-by: Jonathan Billings <jsbillings@jsbillings.org> Signed-off-by: David Howells <dhowells@redhat.com> Acked-by: Kees Cook <keescook@chromium.org> Tested-by: Jonathan Billings <jsbillings@jsbillings.org> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Sasha Levin <alexander.levin@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-04-13rxrpc: check return value of skb_to_sgvec alwaysJason A. Donenfeld1-5/+14
commit 89a5ea99662505d2d61f2a3030a6896c2cb3cdb0 upstream. Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com> Acked-by: David Howells <dhowells@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Nathan Chancellor <natechancellor@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-03-11rxrpc: Fix send in rxrpc_send_data_packet()David Howells1-1/+1
[ Upstream commit 93c62c45ed5fad1b87e3a45835b251cd68de9c46 ] All the kernel_sendmsg() calls in rxrpc_send_data_packet() need to send both parts of the iov[] buffer, but one of them does not. Fix it so that it does. Without this, short IPv6 rxrpc DATA packets may be seen that have the rxrpc header included, but no payload. Fixes: 5a924b8951f8 ("rxrpc: Don't store the rxrpc header in the Tx queue sk_buffs") Reported-by: Marc Dionne <marc.dionne@auristor.com> Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-12-20rxrpc: Ignore BUSY packets on old callsDavid Howells1-0/+4
[ Upstream commit 4d4a6ac73e7466c2085c307fac41f74ce4568a45 ] If we receive a BUSY packet for a call we think we've just completed, the packet is handed off to the connection processor to deal with - but the connection processor doesn't expect a BUSY packet and so flags a protocol error. Fix this by simply ignoring the BUSY packet for the moment. The symptom of this may appear as a system call failing with EPROTO. This may be triggered by pressing ctrl-C under some circumstances. This comes about we abort calls due to interruption by a signal (which we shouldn't do, but that's going to be a large fix and mostly in fs/afs/). What happens is that we abort the call and may also abort follow up calls too (this needs offloading somehoe). So we see a transmission of something like the following sequence of packets: DATA for call N ABORT call N DATA for call N+1 ABORT call N+1 in very quick succession on the same channel. However, the peer may have deferred the processing of the ABORT from the call N to a background thread and thus sees the DATA message from the call N+1 coming in before it has cleared the channel. Thus it sends a BUSY packet[*]. [*] Note that some implementations (OpenAFS, for example) mark the BUSY packet with one plus the callNumber of the call prior to call N. Ordinarily, this would be call N, but there's no requirement for the calls on a channel to be numbered strictly sequentially (the number is required to increase). This is wrong and means that the callNumber in the BUSY packet should be ignored (it really ought to be N+1 since that's what it's in response to). Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Sasha Levin <alexander.levin@verizon.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-12-20rxrpc: Wake up the transmitter if Rx window size increases on the peerDavid Howells1-3/+12
[ Upstream commit 702f2ac87a9a8da23bf8506466bc70175fc970b2 ] The RxRPC ACK packet may contain an extension that includes the peer's current Rx window size for this call. We adjust the local Tx window size to match. However, the transmitter can stall if the receive window is reduced to 0 by the peer and then reopened. This is because the normal way that the transmitter is re-energised is by dropping something out of our Tx queue and thus making space. When a single gap is made, the transmitter is woken up. However, because there's nothing in the Tx queue at this point, this doesn't happen. To fix this, perform a wake_up() any time we see the peer's Rx window size increasing. The observable symptom is that calls start failing on ETIMEDOUT and the following: kAFS: SERVER DEAD state=-62 appears in dmesg. Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Sasha Levin <alexander.levin@verizon.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-06-29rxrpc: Fix several cases where a padded len isn't checked in ticket decodeDavid Howells1-30/+34
commit 5f2f97656ada8d811d3c1bef503ced266fcd53a0 upstream. This fixes CVE-2017-7482. When a kerberos 5 ticket is being decoded so that it can be loaded into an rxrpc-type key, there are several places in which the length of a variable-length field is checked to make sure that it's not going to overrun the available data - but the data is padded to the nearest four-byte boundary and the code doesn't check for this extra. This could lead to the size-remaining variable wrapping and the data pointer going over the end of the buffer. Fix this by making the various variable-length data checks use the padded length. Reported-by: 石磊 <shilei-c@360.cn> Signed-off-by: David Howells <dhowells@redhat.com> Reviewed-by: Marc Dionne <marc.c.dionne@auristor.com> Reviewed-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-10-13rxrpc: Fix checking of error from ip6_route_output()David Howells1-2/+2
ip6_route_output() doesn't return a negative error when it fails, rather the ->error field of the returned dst_entry struct needs to be checked. Reported-by: Dan Carpenter <dan.carpenter@oracle.com> Fixes: 75b54cb57ca3 ("rxrpc: Add IPv6 support") Signed-off-by: David Howells <dhowells@redhat.com>
2016-10-13rxrpc: Fix checker warning by not passing always-zero value to ERR_PTR()David Howells1-1/+1
Fix the following checker warning: net/rxrpc/call_object.c:279 rxrpc_new_client_call() warn: passing zero to 'ERR_PTR' where a value that's always zero is passed to ERR_PTR() so that it can be passed to a tracepoint in an auxiliary pointer field. Just pass NULL instead to the tracepoint. Fixes: a84a46d73050 ("rxrpc: Add some additional call tracing") Reported-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: David Howells <dhowells@redhat.com>
2016-10-06rxrpc: Don't request an ACK on the last DATA packet of a call's Tx phaseDavid Howells1-5/+6
Don't request an ACK on the last DATA packet of a call's Tx phase as for a client there will be a reply packet or some sort of ACK to shift phase. If the ACK is requested, OpenAFS sends a REQUESTED-ACK ACK with soft-ACKs in it and doesn't follow up with a hard-ACK. If we don't set the flag, OpenAFS will send a DELAY ACK that hard-ACKs the reply data, thereby allowing the call to terminate cleanly. Signed-off-by: David Howells <dhowells@redhat.com>
2016-10-06rxrpc: Need to produce an ACK for service op if op takes a long timeDavid Howells5-6/+28
We need to generate a DELAY ACK from the service end of an operation if we start doing the actual operation work and it takes longer than expected. This will hard-ACK the request data and allow the client to release its resources. To make this work: (1) We have to set the ack timer and propose an ACK when the call moves to the RXRPC_CALL_SERVER_ACK_REQUEST and clear the pending ACK and cancel the timer when we start transmitting the reply (the first DATA packet of the reply implicitly ACKs the request phase). (2) It must be possible to set the timer when the caller is holding call->state_lock, so split the lock-getting part of the timer function out. (3) Add trace notes for the ACK we're requesting and the timer we clear. Signed-off-by: David Howells <dhowells@redhat.com>
2016-10-06rxrpc: Return negative error code to kernel serviceDavid Howells1-1/+1
In rxrpc_kernel_recv_data(), when we return the error number incurred by a failed call, we must negate it before returning it as it's stored as positive (that's what we have to pass back to userspace). Signed-off-by: David Howells <dhowells@redhat.com>
2016-10-06rxrpc: Add missing notificationDavid Howells1-0/+1
The call's background processor work item needs to notify the socket when it completes a call so that recvmsg() or the AFS fs can deal with it. Without this, call expiry isn't handled. Signed-off-by: David Howells <dhowells@redhat.com>
2016-10-06rxrpc: Queue the call on expiryDavid Howells1-4/+6
When a call expires, it must be queued for the background processor to deal with otherwise a service call that is improperly terminated will just sit there awaiting an ACK and won't expire. Signed-off-by: David Howells <dhowells@redhat.com>
2016-10-06rxrpc: Partially handle OpenAFS's improper termination of callsDavid Howells1-0/+37
OpenAFS doesn't always correctly terminate client calls that it makes - this includes calls the OpenAFS servers make to the cache manager service. It should end the client call with either: (1) An ACK that has firstPacket set to one greater than the seq number of the reply DATA packet with the LAST_PACKET flag set (thereby hard-ACK'ing all packets). nAcks should be 0 and acks[] should be empty (ie. no soft-ACKs). (2) An ACKALL packet. OpenAFS, though, may send an ACK packet with firstPacket set to the last seq number or less and soft-ACKs listed for all packets up to and including the last DATA packet. The transmitter, however, is obliged to keep the call live and the soft-ACK'd DATA packets around until they're hard-ACK'd as the receiver is permitted to drop any merely soft-ACK'd packet and request retransmission by sending an ACK packet with a NACK in it. Further, OpenAFS will also terminate a client call by beginning the next client call on the same connection channel. This implicitly completes the previous call. This patch handles implicit ACK of a call on a channel by the reception of the first packet of the next call on that channel. If another call doesn't come along to implicitly ACK a call, then we have to time the call out. There are some bugs there that will be addressed in subsequent patches. Signed-off-by: David Howells <dhowells@redhat.com>
2016-10-06rxrpc: Fix loss of PING RESPONSE ACK production due to PING ACKsDavid Howells8-29/+82
Separate the output of PING ACKs from the output of other sorts of ACK so that if we receive a PING ACK and schedule transmission of a PING RESPONSE ACK, the response doesn't get cancelled by a PING ACK we happen to be scheduling transmission of at the same time. If a PING RESPONSE gets lost, the other side might just sit there waiting for it and refuse to proceed otherwise. Signed-off-by: David Howells <dhowells@redhat.com>
2016-10-06rxrpc: Fix warning by splitting rxrpc_send_call_packet()David Howells8-84/+102
Split rxrpc_send_data_packet() to separate ACK generation (which is more complicated) from ABORT generation. This simplifies the code a bit and fixes the following warning: In file included from ../net/rxrpc/output.c:20:0: net/rxrpc/output.c: In function 'rxrpc_send_call_packet': net/rxrpc/ar-internal.h:1187:27: error: 'top' may be used uninitialized in this function [-Werror=maybe-uninitialized] net/rxrpc/output.c:103:24: note: 'top' was declared here net/rxrpc/output.c:225:25: error: 'hard_ack' may be used uninitialized in this function [-Werror=maybe-uninitialized] Reported-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: David Howells <dhowells@redhat.com>
2016-10-06rxrpc: Only ping for lost reply in client callDavid Howells1-1/+2
When a reply is deemed lost, we send a ping to find out the other end received all the request data packets we sent. This should be limited to client calls and we shouldn't do this on service calls. Signed-off-by: David Howells <dhowells@redhat.com>
2016-10-06rxrpc: Fix oops on incoming call to serviceless endpointDavid Howells1-1/+1
If an call comes in to a local endpoint that isn't listening for any incoming calls at the moment, an oops will happen. We need to check that the local endpoint's service pointer isn't NULL before we dereference it. Signed-off-by: David Howells <dhowells@redhat.com>
2016-10-06rxrpc: Fix duplicate constDavid Howells2-2/+2
Remove a duplicate const keyword. Signed-off-by: David Howells <dhowells@redhat.com>
2016-10-06rxrpc: Accesses of rxrpc_local::service need to be RCU managedDavid Howells1-2/+2
struct rxrpc_local->service is marked __rcu - this means that accesses of it need to be managed using RCU wrappers. There are two such places in rxrpc_release_sock() where the value is checked and cleared. Fix this by using the appropriate wrappers. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-30rxrpc: Fix the call timer handlingDavid Howells2-13/+20
The call timer's concept of a call timeout (of which there are three) that is inactive is that it is the timeout has the same expiration time as the call expiration timeout (the expiration timer is never inactive). However, I'm not resetting the timeouts when they expire, leading to repeated processing of expired timeouts when other timeout events occur. Fix this by: (1) Move the timer expiry detection into rxrpc_set_timer() inside the locked section. This means that if a timeout is set that will expire immediately, we deal with it immediately. (2) If a timeout is at or before now then it has expired. When an expiry is detected, an event is raised, the timeout is automatically inactivated and the event processor is queued. (3) If a timeout is at or after the expiry timeout then it is inactive. Inactive timeouts do not contribute to the timer setting. (4) The call timer callback can now just call rxrpc_set_timer() to handle things. (5) The call processor work function now checks the event flags rather than checking the timeouts directly. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-30rxrpc: Keep the call timeouts as ktimes rather than jiffiesDavid Howells7-62/+69
Keep that call timeouts as ktimes rather than jiffies so that they can be expressed as functions of RTT. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-30rxrpc: Remove error from struct rxrpc_skb_priv as it is unusedDavid Howells1-1/+0
Remove error from struct rxrpc_skb_priv as it is no longer used. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-30rxrpc: The offset field in struct rxrpc_skb_priv is unnecessaryDavid Howells6-21/+24
The offset field in struct rxrpc_skb_priv is unnecessary as the value can always be calculated. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-30rxrpc: Reduce ssthresh to peer's receive windowDavid Howells1-0/+2
When we receive an ACK from the peer that tells us what the peer's receive window (rwind) is, we should reduce ssthresh to rwind if rwind is smaller than ssthresh. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-30rxrpc: Switch to Congestion Avoidance mode at cwnd==ssthreshDavid Howells1-3/+3
Switch to Congestion Avoidance mode at cwnd == ssthresh rather than relying on cwnd getting incremented beyond ssthresh and the window size, the mode being shifted and then cwnd being corrected. We need to make sure we switch into CA mode so that we stop marking every packet for ACK. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-30rxrpc: Note serial number being ACK'd in the congestion management traceDavid Howells1-4/+4
Note the serial number of the packet being ACK'd in the congestion management trace rather than the serial number of the ACK packet. Whilst the serial number of the ACK packet is useful for matching ACK packet in the output of wireshark, the serial number that the ACK is in response to is of more use in working out how different trace lines relate. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-30rxrpc: Request more ACKs in slow-start modeDavid Howells1-0/+1
Set the request-ACK on more DATA packets whilst we're in slow start mode so that we get sufficient ACKs back to supply information to configure the window. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-30rxrpc: Reduce the rxrpc_local::services list to a pointerDavid Howells5-25/+18
Reduce the rxrpc_local::services list to just a pointer as we don't permit multiple service endpoints to bind to a single transport endpoints (this is excluded by rxrpc_lookup_local()). The reason we don't allow this is that if you send a request to an AFS filesystem service, it will try to talk back to your cache manager on the port you sent from (this is how file change notifications are handled). To prevent someone from stealing your CM callbacks, we don't let AF_RXRPC sockets share a UDP socket if at least one of them has a service bound. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-30rxrpc: When activating client conn channels, do state check inside lockDavid Howells1-11/+25
In rxrpc_activate_channels(), the connection cache state is checked outside of the lock, which means it can change whilst we're waking calls up, thereby changing whether or not we're allowed to wake calls up. Fix this by moving the check inside the locked region. The check to see if all the channels are currently busy can stay outside of the locked region. Whilst we're at it: (1) Split the locked section out into its own function so that we can call it from other places in a later patch. (2) Determine the mask of channels dependent on the state as we're going to add another state in a later patch that will restrict the number of simultaneous calls to 1 on a connection. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-30rxrpc: Make Tx loss-injection go through normal return and adjust tracingDavid Howells6-21/+15
In rxrpc_send_data_packet() make the loss-injection path return through the same code as the transmission path so that the RTT determination is initiated and any future timer shuffling will be done, despite the packet having been binned. Whilst we're at it: (1) Add to the tx_data tracepoint an indication of whether or not we're retransmitting a data packet. (2) When we're deciding whether or not to request an ACK, rather than checking if we're in fast-retransmit mode check instead if we're retransmitting. (3) Don't invoke the lose_skb tracepoint when losing a Tx packet as we're not altering the sk_buff refcount nor are we just seeing it after getting it off the Tx list. (4) The rxrpc_skb_tx_lost note is then no longer used so remove it. (5) rxrpc_lose_skb() no longer needs to deal with rxrpc_skb_tx_lost. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-30rxrpc: Fix exclusive client connectionsDavid Howells1-1/+1
Exclusive connections are currently reusable (which they shouldn't be) because rxrpc_alloc_client_connection() checks the exclusive flag in the rxrpc_connection struct before it's initialised from the function parameters. This means that the DONT_REUSE flag doesn't get set. Fix this by checking the function parameters for the exclusive flag. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-25rxrpc: Implement slow-startDavid Howells8-13/+294
Implement RxRPC slow-start, which is similar to RFC 5681 for TCP. A tracepoint is added to log the state of the congestion management algorithm and the decisions it makes. Notes: (1) Since we send fixed-size DATA packets (apart from the final packet in each phase), counters and calculations are in terms of packets rather than bytes. (2) The ACK packet carries the equivalent of TCP SACK. (3) The FLIGHT_SIZE calculation in RFC 5681 doesn't seem particularly suited to SACK of a small number of packets. It seems that, almost inevitably, by the time three 'duplicate' ACKs have been seen, we have narrowed the loss down to one or two missing packets, and the FLIGHT_SIZE calculation ends up as 2. (4) In rxrpc_resend(), if there was no data that apparently needed retransmission, we transmit a PING ACK to ask the peer to tell us what its Rx window state is. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-25rxrpc: Schedule an ACK if the reply to a client call appears overdueDavid Howells4-0/+13
If we've sent all the request data in a client call but haven't seen any sign of the reply data yet, schedule an ACK to be sent to the server to find out if the reply data got lost. If the server hasn't yet hard-ACK'd the request data, we send a PING ACK to demand a response to find out whether we need to retransmit. If the server says it has received all of the data, we send an IDLE ACK to tell the server that we haven't received anything in the receive phase as yet. To make this work, a non-immediate PING ACK must carry a delay. I've chosen the same as the IDLE ACK for the moment. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-25rxrpc: Generate a summary of the ACK state for later useDavid Howells2-11/+48
Generate a summary of the Tx buffer packet state when an ACK is received for use in a later patch that does congestion management. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-25rxrpc: Delay the resend timer to allow for nsec->jiffies conv errorDavid Howells1-2/+8
When determining the resend timer value, we have a value in nsec but the timer is in jiffies which may be a million or more times more coarse. nsecs_to_jiffies() rounds down - which means that the resend timeout expressed as jiffies is very likely earlier than the one expressed as nanoseconds from which it was derived. The problem is that rxrpc_resend() gets triggered by the timer, but can't then find anything to resend yet. It sets the timer again - but gets kicked off immediately again and again until the nanosecond-based expiry time is reached and we actually retransmit. Fix this by adding 1 to the jiffies-based resend_at value to counteract the rounding and make sure that the timer happens after the nanosecond-based expiry is passed. Alternatives would be to adjust the timestamp on the packets to align with the jiffie scale or to switch back to using jiffie-timestamps. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-25rxrpc: Reinitialise the call ACK and timer state for client reply phaseDavid Howells3-0/+11
Clear the ACK reason, ACK timer and resend timer when entering the client reply phase when the first DATA packet is received. New ACKs will be proposed once the data is queued. The resend timer is no longer relevant and we need to cancel ACKs scheduled to probe for a lost reply. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-25rxrpc: Include the last reply DATA serial number in the final ACKDavid Howells1-3/+3
In a client call, include the serial number of the last DATA packet of the reply in the final ACK. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-25rxrpc: Send an immediate ACK if we fill in a holeDavid Howells1-1/+9
Send an immediate ACK if we fill in a hole in the buffer left by an out-of-sequence packet. This may allow the congestion management in the peer to avoid a retransmission if packets got reordered on the wire. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-24rxrpc: Send an ACK after every few DATA packets we receiveDavid Howells4-9/+33
Send an ACK if we haven't sent one for the last two packets we've received. This keeps the other end apprised of where we've got to - which is important if they're doing slow-start. We do this in recvmsg so that we can dispatch a packet directly without the need to wake up the background thread. This should possibly be made configurable in future. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-23rxrpc: Add a tracepoint to log which packets will be retransmittedDavid Howells1-0/+2
Add a tracepoint to log in rxrpc_resend() which packets will be retransmitted. Note that if a positive ACK comes in whilst we have dropped the lock to retransmit another packet, the actual retransmission may not happen, though some of the effects will (such as altering the congestion management). Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-23rxrpc: Add tracepoint for ACK proposalDavid Howells6-28/+73
Add a tracepoint to log proposed ACKs, including whether the proposal is used to update a pending ACK or is discarded in favour of an easlier, higher priority ACK. Whilst we're at it, get rid of the rxrpc_acks() function and access the name array directly. We do, however, need to validate the ACK reason number given to trace_rxrpc_rx_ack() to make sure we don't overrun the array. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-23rxrpc: Add a tracepoint to log injected Rx packet lossDavid Howells1-6/+5
Add a tracepoint to log received packets that get discarded due to Rx packet loss. Signed-off-by: David Howells <dhowells@redhat.com>