kernel/linux.git/net/rxrpc/sendmsg.c, branch v6.6.132

rxrpc: Fix call state set to not include the SERVER_SECURING state

2025-02-17T08:40:14+00:00

[ Upstream commit 41b996ce83bf944de5569d6263c8dbd5513e7ed0 ] The RXRPC_CALL_SERVER_SECURING state doesn't really belong with the other states in the call's state set as the other states govern the call's Rx/Tx phase transition and govern when packets can and can't be received or transmitted. The "Securing" state doesn't actually govern the reception of packets and would need to be split depending on whether or not we've received the last packet yet (to mirror RECV_REQUEST/ACK_REQUEST). The "Securing" state is more about whether or not we can start forwarding packets to the application as recvmsg will need to decode them and the decoding can't take place until the challenge/response exchange has completed. Fix this by removing the RXRPC_CALL_SERVER_SECURING state from the state set and, instead, using a flag, RXRPC_CALL_CONN_CHALLENGING, to track whether or not we can queue the call for reception by recvmsg() or notify the kernel app that data is ready. In the event that we've already received all the packets, the connection event handler will poke the app layer in the appropriate manner. Also there's a race whereby the app layer sees the last packet before rxrpc has managed to end the rx phase and change the state to one amenable to allowing a reply. Fix this by queuing the packet after calling rxrpc_end_rx_phase(). Fixes: 17926a79320a ("[AF_RXRPC]: Provide secure RxRPC sockets for use by userspace and kernel both") Signed-off-by: David Howells cc: Marc Dionne cc: Simon Horman cc: linux-afs@lists.infradead.org Link: https://patch.msgid.link/20250204230558.712536-2-dhowells@redhat.com Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin

rxrpc: Fix uninitialised variable in rxrpc_send_data()

2024-10-17T13:24:24+00:00

[ Upstream commit 7a310f8d7dfe2d92a1f31ddb5357bfdd97eed273 ] Fix the uninitialised txb variable in rxrpc_send_data() by moving the code that loads it above all the jumps to maybe_error, txb being stored back into call->tx_pending right before the normal return. Fixes: b0f571ecd794 ("rxrpc: Fix locking in rxrpc's sendmsg") Reported-by: Dan Carpenter Closes: https://lists.infradead.org/pipermail/linux-afs/2024-October/008896.html Signed-off-by: David Howells cc: Marc Dionne cc: linux-afs@lists.infradead.org Link: https://patch.msgid.link/20241001132702.3122709-3-dhowells@redhat.com Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin

rxrpc: Fix timeout of a call that hasn't yet been granted a channel

2023-05-01T06:43:19+00:00

afs_make_call() calls rxrpc_kernel_begin_call() to begin a call (which may get stalled in the background waiting for a connection to become available); it then calls rxrpc_kernel_set_max_life() to set the timeouts - but that starts the call timer so the call timer might then expire before we get a connection assigned - leading to the following oops if the call stalled: BUG: kernel NULL pointer dereference, address: 0000000000000000 ... CPU: 1 PID: 5111 Comm: krxrpcio/0 Not tainted 6.3.0-rc7-build3+ #701 RIP: 0010:rxrpc_alloc_txbuf+0xc0/0x157 ... Call Trace: rxrpc_send_ACK+0x50/0x13b rxrpc_input_call_event+0x16a/0x67d rxrpc_io_thread+0x1b6/0x45f ? _raw_spin_unlock_irqrestore+0x1f/0x35 ? rxrpc_input_packet+0x519/0x519 kthread+0xe7/0xef ? kthread_complete_and_exit+0x1b/0x1b ret_from_fork+0x22/0x30 Fix this by noting the timeouts in struct rxrpc_call when the call is created. The timer will be started when the first packet is transmitted. It shouldn't be possible to trigger this directly from userspace through AF_RXRPC as sendmsg() will return EBUSY if the call is in the waiting-for-conn state if it dropped out of the wait due to a signal. Fixes: 9d35d880e0e4 ("rxrpc: Move client call connection to the I/O thread") Reported-by: Marc Dionne Signed-off-by: David Howells cc: "David S. Miller" cc: Eric Dumazet cc: Jakub Kicinski cc: Paolo Abeni cc: linux-afs@lists.infradead.org cc: netdev@vger.kernel.org cc: linux-kernel@vger.kernel.org Signed-off-by: David S. Miller

rxrpc: Make it so that a waiting process can be aborted

2023-05-01T06:43:19+00:00

When sendmsg() creates an rxrpc call, it queues it to wait for a connection and channel to be assigned and then waits before it can start shovelling data as the encrypted DATA packet content includes a summary of the connection parameters. However, sendmsg() may get interrupted before a connection gets assigned and further sendmsg() calls will fail with EBUSY until an assignment is made. Fix this so that the call can at least be aborted without failing on EBUSY. We have to be careful here as sendmsg() mustn't be allowed to start the call timer if the call doesn't yet have a connection assigned as an oops may follow shortly thereafter. Fixes: 540b1c48c37a ("rxrpc: Fix deadlock between call creation and sendmsg/recvmsg") Reported-by: Marc Dionne Signed-off-by: David Howells cc: "David S. Miller" cc: Eric Dumazet cc: Jakub Kicinski cc: Paolo Abeni cc: linux-afs@lists.infradead.org cc: netdev@vger.kernel.org cc: linux-kernel@vger.kernel.org Signed-off-by: David S. Miller

rxrpc: Fix hard call timeout units

2023-05-01T06:43:19+00:00

The hard call timeout is specified in the RXRPC_SET_CALL_TIMEOUT cmsg in seconds, so fix the point at which sendmsg() applies it to the call to convert to jiffies from seconds, not milliseconds. Fixes: a158bdd3247b ("rxrpc: Fix timeout of a call that hasn't yet been granted a channel") Signed-off-by: David Howells cc: Marc Dionne cc: "David S. Miller" cc: Eric Dumazet cc: Jakub Kicinski cc: Paolo Abeni cc: linux-afs@lists.infradead.org cc: netdev@vger.kernel.org cc: linux-kernel@vger.kernel.org Signed-off-by: David S. Miller

rxrpc: Fix potential data race in rxrpc_wait_to_be_connected()

2023-04-27T07:17:41+00:00

Inside the loop in rxrpc_wait_to_be_connected() it checks call->error to see if it should exit the loop without first checking the call state. This is probably safe as if call->error is set, the call is dead anyway, but we should probably wait for the call state to have been set to completion first, lest it cause surprise on the way out. Fix this by only accessing call->error if the call is complete. We don't actually need to access the error inside the loop as we'll do that after. This caused the following report: BUG: KCSAN: data-race in rxrpc_send_data / rxrpc_set_call_completion write to 0xffff888159cf3c50 of 4 bytes by task 25673 on cpu 1: rxrpc_set_call_completion+0x71/0x1c0 net/rxrpc/call_state.c:22 rxrpc_send_data_packet+0xba9/0x1650 net/rxrpc/output.c:479 rxrpc_transmit_one+0x1e/0x130 net/rxrpc/output.c:714 rxrpc_decant_prepared_tx net/rxrpc/call_event.c:326 [inline] rxrpc_transmit_some_data+0x496/0x600 net/rxrpc/call_event.c:350 rxrpc_input_call_event+0x564/0x1220 net/rxrpc/call_event.c:464 rxrpc_io_thread+0x307/0x1d80 net/rxrpc/io_thread.c:461 kthread+0x1ac/0x1e0 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308 read to 0xffff888159cf3c50 of 4 bytes by task 25672 on cpu 0: rxrpc_send_data+0x29e/0x1950 net/rxrpc/sendmsg.c:296 rxrpc_do_sendmsg+0xb7a/0xc20 net/rxrpc/sendmsg.c:726 rxrpc_sendmsg+0x413/0x520 net/rxrpc/af_rxrpc.c:565 sock_sendmsg_nosec net/socket.c:724 [inline] sock_sendmsg net/socket.c:747 [inline] ____sys_sendmsg+0x375/0x4c0 net/socket.c:2501 ___sys_sendmsg net/socket.c:2555 [inline] __sys_sendmmsg+0x263/0x500 net/socket.c:2641 __do_sys_sendmmsg net/socket.c:2670 [inline] __se_sys_sendmmsg net/socket.c:2667 [inline] __x64_sys_sendmmsg+0x57/0x60 net/socket.c:2667 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 -> 0xffffffea Fixes: 9d35d880e0e4 ("rxrpc: Move client call connection to the I/O thread") Reported-by: syzbot+ebc945fdb4acd72cba78@syzkaller.appspotmail.com Link: https://lore.kernel.org/r/000000000000e7c6d205fa10a3cd@google.com/ Signed-off-by: David Howells cc: Marc Dionne cc: Dmitry Vyukov cc: "David S. Miller" cc: Eric Dumazet cc: Jakub Kicinski cc: Paolo Abeni cc: linux-afs@lists.infradead.org cc: linux-fsdevel@vger.kernel.org cc: netdev@vger.kernel.org Link: https://lore.kernel.org/r/508133.1682427395@warthog.procyon.org.uk Signed-off-by: Paolo Abeni

rxrpc: Move client call connection to the I/O thread

2023-01-06T09:43:33+00:00

Move the connection setup of client calls to the I/O thread so that a whole load of locking and barrierage can be eliminated. This necessitates the app thread waiting for connection to complete before it can begin encrypting data. This also completes the fix for a race that exists between call connection and call disconnection whereby the data transmission code adds the call to the peer error distribution list after the call has been disconnected (say by the rxrpc socket getting closed). The fix is to complete the process of moving call connection, data transmission and call disconnection into the I/O thread and thus forcibly serialising them. Note that the issue may predate the overhaul to an I/O thread model that were included in the merge window for v6.2, but the timing is very much changed by the change given below. Fixes: cf37b5987508 ("rxrpc: Move DATA transmission into call processor work item") Reported-by: syzbot+c22650d2844392afdcfd@syzkaller.appspotmail.com Signed-off-by: David Howells cc: Marc Dionne cc: linux-afs@lists.infradead.org

rxrpc: Remove call->state_lock

2023-01-06T09:43:33+00:00

All the setters of call->state are now in the I/O thread and thus the state lock is now unnecessary. Signed-off-by: David Howells cc: Marc Dionne cc: linux-afs@lists.infradead.org

rxrpc: Move call state changes from sendmsg to I/O thread

2023-01-06T09:43:33+00:00

Move all the call state changes that are made in rxrpc_sendmsg() to the I/O thread. This is a step towards removing the call state lock. This requires the switch to the RXRPC_CALL_CLIENT_AWAIT_REPLY and RXRPC_CALL_SERVER_SEND_REPLY states to be done when the last packet is decanted from ->tx_sendmsg to ->tx_buffer in the I/O thread, not when it is added to ->tx_sendmsg by sendmsg(). Signed-off-by: David Howells cc: Marc Dionne cc: linux-afs@lists.infradead.org

rxrpc: Wrap accesses to get call state to put the barrier in one place

2023-01-06T09:43:32+00:00

Wrap accesses to get the state of a call from outside of the I/O thread in a single place so that the barrier needed to order wrt the error code and abort code is in just that place. Also use a barrier when setting the call state and again when reading the call state such that the auxiliary completion info (error code, abort code) can be read without taking a read lock on the call state lock. Signed-off-by: David Howells cc: Marc Dionne cc: linux-afs@lists.infradead.org