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2023-02-21Merge tag 'hardening-v6.3-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux Pull hardening updates from Kees Cook: "Beyond some specific LoadPin, UBSAN, and fortify features, there are other fixes scattered around in various subsystems where maintainers were okay with me carrying them in my tree or were non-responsive but the patches were reviewed by others: - Replace 0-length and 1-element arrays with flexible arrays in various subsystems (Paulo Miguel Almeida, Stephen Rothwell, Kees Cook) - randstruct: Disable Clang 15 support (Eric Biggers) - GCC plugins: Drop -std=gnu++11 flag (Sam James) - strpbrk(): Refactor to use strchr() (Andy Shevchenko) - LoadPin LSM: Allow root filesystem switching when non-enforcing - fortify: Use dynamic object size hints when available - ext4: Fix CFI function prototype mismatch - Nouveau: Fix DP buffer size arguments - hisilicon: Wipe entire crypto DMA pool on error - coda: Fully allocate sig_inputArgs - UBSAN: Improve arm64 trap code reporting - copy_struct_from_user(): Add minimum bounds check on kernel buffer size" * tag 'hardening-v6.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux: randstruct: disable Clang 15 support uaccess: Add minimum bounds check on kernel buffer size arm64: Support Clang UBSAN trap codes for better reporting coda: Avoid partial allocation of sig_inputArgs gcc-plugins: drop -std=gnu++11 to fix GCC 13 build lib/string: Use strchr() in strpbrk() crypto: hisilicon: Wipe entire pool on error net/i40e: Replace 0-length array with flexible array io_uring: Replace 0-length array with flexible array ext4: Fix function prototype mismatch for ext4_feat_ktype i915/gvt: Replace one-element array with flexible-array member drm/nouveau/disp: Fix nvif_outp_acquire_dp() argument size LoadPin: Allow filesystem switch when not enforcing LoadPin: Move pin reporting cleanly out of locking LoadPin: Refactor sysctl initialization LoadPin: Refactor read-only check into a helper ARM: ixp4xx: Replace 0-length arrays with flexible arrays fortify: Use __builtin_dynamic_object_size() when available rxrpc: replace zero-lenth array with DECLARE_FLEX_ARRAY() helper
2023-02-03rxrpc: use bvec_set_page to initialize a bvecChristoph Hellwig
Use the bvec_set_page helper to initialize a bvec. Signed-off-by: Christoph Hellwig <hch@lst.de> Acked-by: David Howells <dhowells@redhat.com> Link: https://lore.kernel.org/r/20230203150634.3199647-21-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2023-01-12rxrpc: Fix wrong error return in rxrpc_connect_call()David Howells
Fix rxrpc_connect_call() to return -ENOMEM rather than 0 if it fails to look up a peer. This generated a smatch warning: net/rxrpc/call_object.c:303 rxrpc_connect_call() warn: missing error code 'ret' I think this also fixes a syzbot-found bug: rxrpc: Assertion failed - 1(0x1) == 11(0xb) is false ------------[ cut here ]------------ kernel BUG at net/rxrpc/call_object.c:645! where the call being put is in the wrong state - as would be the case if we failed to clear up correctly after the error in rxrpc_connect_call(). Fixes: 9d35d880e0e4 ("rxrpc: Move client call connection to the I/O thread") Reported-by: kernel test robot <lkp@intel.com> Reported-by: Dan Carpenter <error27@gmail.com> Reported-and-tested-by: syzbot+4bb6356bb29d6299360e@syzkaller.appspotmail.com Signed-off-by: David Howells <dhowells@redhat.com> Link: https://lore.kernel.org/r/202301111153.9eZRYLf1-lkp@intel.com/ Reviewed-by: Alexander Duyck <alexanderduyck@fb.com> Link: https://lore.kernel.org/r/2438405.1673460435@warthog.procyon.org.uk Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-01-07rxrpc: Fix incoming call setup raceDavid Howells
An incoming call can race with rxrpc socket destruction, leading to a leaked call. This may result in an oops when the call timer eventually expires: BUG: kernel NULL pointer dereference, address: 0000000000000874 RIP: 0010:_raw_spin_lock_irqsave+0x2a/0x50 Call Trace: <IRQ> try_to_wake_up+0x59/0x550 ? __local_bh_enable_ip+0x37/0x80 ? rxrpc_poke_call+0x52/0x110 [rxrpc] ? rxrpc_poke_call+0x110/0x110 [rxrpc] ? rxrpc_poke_call+0x110/0x110 [rxrpc] call_timer_fn+0x24/0x120 with a warning in the kernel log looking something like: rxrpc: Call 00000000ba5e571a still in use (1,SvAwtACK,1061d,0)! incurred during rmmod of rxrpc. The 1061d is the call flags: RECVMSG_READ_ALL, RX_HEARD, BEGAN_RX_TIMER, RX_LAST, EXPOSED, IS_SERVICE, RELEASED but no DISCONNECTED flag (0x800), so it's an incoming (service) call and it's still connected. The race appears to be that: (1) rxrpc_new_incoming_call() consults the service struct, checks sk_state and allocates a call - then pauses, possibly for an interrupt. (2) rxrpc_release_sock() sets RXRPC_CLOSE, nulls the service pointer, discards the prealloc and releases all calls attached to the socket. (3) rxrpc_new_incoming_call() resumes, launching the new call, including its timer and attaching it to the socket. Fix this by read-locking local->services_lock to access the AF_RXRPC socket providing the service rather than RCU in rxrpc_new_incoming_call(). There's no real need to use RCU here as local->services_lock is only write-locked by the socket side in two places: when binding and when shutting down. Fixes: 5e6ef4f1017c ("rxrpc: Make the I/O thread take over the call and local processor work") Reported-by: Marc Dionne <marc.dionne@auristor.com> Signed-off-by: David Howells <dhowells@redhat.com> cc: linux-afs@lists.infradead.org
2023-01-06rxrpc: Move client call connection to the I/O threadDavid Howells
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 <dhowells@redhat.com> cc: Marc Dionne <marc.dionne@auristor.com> cc: linux-afs@lists.infradead.org
2023-01-06rxrpc: Move the client conn cache management to the I/O threadDavid Howells
Move the management of the client connection cache to the I/O thread rather than managing it from the namespace as an aggregate across all the local endpoints within the namespace. This will allow a load of locking to be got rid of in a future patch as only the I/O thread will be looking at the this. The downside is that the total number of cached connections on the system can get higher because the limit is now per-local rather than per-netns. We can, however, keep the number of client conns in use across the entire netfs and use that to reduce the expiration time of idle connection. Signed-off-by: David Howells <dhowells@redhat.com> cc: Marc Dionne <marc.dionne@auristor.com> cc: linux-afs@lists.infradead.org
2023-01-06rxrpc: Remove call->state_lockDavid Howells
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 <dhowells@redhat.com> cc: Marc Dionne <marc.dionne@auristor.com> cc: linux-afs@lists.infradead.org
2023-01-06rxrpc: Move call state changes from recvmsg to I/O threadDavid Howells
Move the call state changes that are made in rxrpc_recvmsg() to the I/O thread. This means that, thenceforth, only the I/O thread does this and the call state lock can be removed. This requires the Rx phase to be ended when the last packet is received, not when it is processed. Since this now changes the rxrpc call state to SUCCEEDED before we've consumed all the data from it, rxrpc_kernel_check_life() mustn't say the call is dead until the recvmsg queue is empty (unless the call has failed). Signed-off-by: David Howells <dhowells@redhat.com> cc: Marc Dionne <marc.dionne@auristor.com> cc: linux-afs@lists.infradead.org
2023-01-06rxrpc: Move call state changes from sendmsg to I/O threadDavid Howells
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 <dhowells@redhat.com> cc: Marc Dionne <marc.dionne@auristor.com> cc: linux-afs@lists.infradead.org
2023-01-06rxrpc: Wrap accesses to get call state to put the barrier in one placeDavid Howells
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 <dhowells@redhat.com> cc: Marc Dionne <marc.dionne@auristor.com> cc: linux-afs@lists.infradead.org
2023-01-06rxrpc: Split out the call state changing functions into their own fileDavid Howells
Split out the functions that change the state of an rxrpc call into their own file. The idea being to remove anything to do with changing the state of a call directly from the rxrpc sendmsg() and recvmsg() paths and have all that done in the I/O thread only, with the ultimate aim of removing the state lock entirely. Moving the code out of sendmsg.c and recvmsg.c makes that easier to manage. Signed-off-by: David Howells <dhowells@redhat.com> cc: Marc Dionne <marc.dionne@auristor.com> cc: linux-afs@lists.infradead.org
2023-01-06rxrpc: Set up a connection bundle from a call, not rxrpc_conn_parametersDavid Howells
Use the information now stored in struct rxrpc_call to configure the connection bundle and thence the connection, rather than using the rxrpc_conn_parameters struct. Signed-off-by: David Howells <dhowells@redhat.com> cc: Marc Dionne <marc.dionne@auristor.com> cc: linux-afs@lists.infradead.org
2023-01-06rxrpc: Offload the completion of service conn security to the I/O threadDavid Howells
Offload the completion of the challenge/response cycle on a service connection to the I/O thread. After the RESPONSE packet has been successfully decrypted and verified by the work queue, offloading the changing of the call states to the I/O thread makes iteration over the conn's channel list simpler. Do this by marking the RESPONSE skbuff and putting it onto the receive queue for the I/O thread to collect. We put it on the front of the queue as we've already received the packet for it. Signed-off-by: David Howells <dhowells@redhat.com> cc: Marc Dionne <marc.dionne@auristor.com> cc: linux-afs@lists.infradead.org
2023-01-06rxrpc: Make the set of connection IDs per local endpointDavid Howells
Make the set of connection IDs per local endpoint so that endpoints don't cause each other's connections to get dismissed. Signed-off-by: David Howells <dhowells@redhat.com> cc: Marc Dionne <marc.dionne@auristor.com> cc: linux-afs@lists.infradead.org
2023-01-06rxrpc: Tidy up abort generation infrastructureDavid Howells
Tidy up the abort generation infrastructure in the following ways: (1) Create an enum and string mapping table to list the reasons an abort might be generated in tracing. (2) Replace the 3-char string with the values from (1) in the places that use that to log the abort source. This gets rid of a memcpy() in the tracepoint. (3) Subsume the rxrpc_rx_eproto tracepoint with the rxrpc_abort tracepoint and use values from (1) to indicate the trace reason. (4) Always make a call to an abort function at the point of the abort rather than stashing the values into variables and using goto to get to a place where it reported. The C optimiser will collapse the calls together as appropriate. The abort functions return a value that can be returned directly if appropriate. Note that this extends into afs also at the points where that generates an abort. To aid with this, the afs sources need to #define RXRPC_TRACE_ONLY_DEFINE_ENUMS before including the rxrpc tracing header because they don't have access to the rxrpc internal structures that some of the tracepoints make use of. Signed-off-by: David Howells <dhowells@redhat.com> cc: Marc Dionne <marc.dionne@auristor.com> cc: linux-afs@lists.infradead.org
2023-01-06rxrpc: Clean up connection abortDavid Howells
Clean up connection abort, using the connection state_lock to gate access to change that state, and use an rxrpc_call_completion value to indicate the difference between local and remote aborts as these can be pasted directly into the call state. Signed-off-by: David Howells <dhowells@redhat.com> cc: Marc Dionne <marc.dionne@auristor.com> cc: linux-afs@lists.infradead.org
2023-01-06rxrpc: Implement a mechanism to send an event notification to a connectionDavid Howells
Provide a means by which an event notification can be sent to a connection through such that the I/O thread can pick it up and handle it rather than doing it in a separate workqueue. This is then used to move the deferred final ACK of a call into the I/O thread rather than a separate work queue as part of the drive to do all transmission from the I/O thread. Signed-off-by: David Howells <dhowells@redhat.com> cc: Marc Dionne <marc.dionne@auristor.com> cc: linux-afs@lists.infradead.org
2023-01-06rxrpc: Only disconnect calls in the I/O threadDavid Howells
Only perform call disconnection in the I/O thread to reduce the locking requirement. This is the first part of a 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 <dhowells@redhat.com> cc: Marc Dionne <marc.dionne@auristor.com> cc: linux-afs@lists.infradead.org
2023-01-06rxrpc: Only set/transmit aborts in the I/O threadDavid Howells
Only set the abort call completion state in the I/O thread and only transmit ABORT packets from there. rxrpc_abort_call() can then be made to actually send the packet. Further, ABORT packets should only be sent if the call has been exposed to the network (ie. at least one attempted DATA transmission has occurred for it). Signed-off-by: David Howells <dhowells@redhat.com> cc: Marc Dionne <marc.dionne@auristor.com> cc: linux-afs@lists.infradead.org
2023-01-06rxrpc: Separate call retransmission from other conn eventsDavid Howells
Call the rxrpc_conn_retransmit_call() directly from rxrpc_input_packet() rather than calling it via connection event handling. Signed-off-by: David Howells <dhowells@redhat.com> cc: Marc Dionne <marc.dionne@auristor.com> cc: linux-afs@lists.infradead.org
2023-01-06rxrpc: Make the local endpoint hold a ref on a connected callDavid Howells
Make the local endpoint and it's I/O thread hold a reference on a connected call until that call is disconnected. Without this, we're reliant on either the AF_RXRPC socket to hold a ref (which is dropped when the call is released) or a queued work item to hold a ref (the work item is being replaced with the I/O thread). Signed-off-by: David Howells <dhowells@redhat.com> cc: Marc Dionne <marc.dionne@auristor.com> cc: linux-afs@lists.infradead.org
2023-01-06rxrpc: Stash the network namespace pointer in rxrpc_localDavid Howells
Stash the network namespace pointer in the rxrpc_local struct in addition to a pointer to the rxrpc-specific net namespace info. Use this to remove some places where the socket is passed as a parameter. Signed-off-by: David Howells <dhowells@redhat.com> cc: Marc Dionne <marc.dionne@auristor.com> cc: linux-afs@lists.infradead.org
2023-01-05rxrpc: replace zero-lenth array with DECLARE_FLEX_ARRAY() helperStephen Rothwell
0-length arrays are deprecated, and cause problems with bounds checking. Replace with a flexible array: In file included from include/linux/string.h:253, from include/linux/bitmap.h:11, from include/linux/cpumask.h:12, from arch/x86/include/asm/paravirt.h:17, from arch/x86/include/asm/cpuid.h:62, from arch/x86/include/asm/processor.h:19, from arch/x86/include/asm/cpufeature.h:5, from arch/x86/include/asm/thread_info.h:53, from include/linux/thread_info.h:60, from arch/x86/include/asm/preempt.h:9, from include/linux/preempt.h:78, from include/linux/percpu.h:6, from include/linux/prandom.h:13, from include/linux/random.h:153, from include/linux/net.h:18, from net/rxrpc/output.c:10: In function 'fortify_memcpy_chk', inlined from 'rxrpc_fill_out_ack' at net/rxrpc/output.c:158:2: include/linux/fortify-string.h:520:25: error: call to '__write_overflow_field' declared with attribute warning: detected write beyond size of field (1st parameter); maybe use struct_group()? [-Werror=attribute-warning] 520 | __write_overflow_field(p_size_field, size); | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Link: https://lore.kernel.org/linux-next/20230105132535.0d65378f@canb.auug.org.au/ Cc: David Howells <dhowells@redhat.com> Cc: Marc Dionne <marc.dionne@auristor.com> Cc: "David S. Miller" <davem@davemloft.net> Cc: Eric Dumazet <edumazet@google.com> Cc: Jakub Kicinski <kuba@kernel.org> Cc: Paolo Abeni <pabeni@redhat.com> Cc: linux-afs@lists.infradead.org Cc: netdev@vger.kernel.org Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Kees Cook <keescook@chromium.org>
2022-12-28rxrpc: Fix a couple of potential use-after-freesDavid Howells
At the end of rxrpc_recvmsg(), if a call is found, the call is put and then a trace line is emitted referencing that call in a couple of places - but the call may have been deallocated by the time those traces happen. Fix this by stashing the call debug_id in a variable and passing that to the tracepoint rather than the call pointer. Fixes: 849979051cbc ("rxrpc: Add a tracepoint to follow what recvmsg does") Signed-off-by: David Howells <dhowells@redhat.com> cc: Marc Dionne <marc.dionne@auristor.com> cc: linux-afs@lists.infradead.org Signed-off-by: David S. Miller <davem@davemloft.net>
2022-12-19rxrpc: Fix the return value of rxrpc_new_incoming_call()David Howells
Dan Carpenter sayeth[1]: The patch 5e6ef4f1017c: "rxrpc: Make the I/O thread take over the call and local processor work" from Jan 23, 2020, leads to the following Smatch static checker warning: net/rxrpc/io_thread.c:283 rxrpc_input_packet() warn: bool is not less than zero. Fix this (for now) by changing rxrpc_new_incoming_call() to return an int with 0 or error code rather than bool. Note that the actual return value of rxrpc_input_packet() is currently ignored. I have a separate patch to clean that up. Fixes: 5e6ef4f1017c ("rxrpc: Make the I/O thread take over the call and local processor work") Reported-by: Dan Carpenter <error27@gmail.com> Signed-off-by: David Howells <dhowells@redhat.com> cc: Marc Dionne <marc.dionne@auristor.com> cc: linux-afs@lists.infradead.org Link: http://lists.infradead.org/pipermail/linux-afs/2022-December/006123.html [1] Signed-off-by: David S. Miller <davem@davemloft.net>
2022-12-19rxrpc: rxperf: Fix uninitialised variableDavid Howells
Dan Carpenter sayeth[1]: The patch 75bfdbf2fca3: "rxrpc: Implement an in-kernel rxperf server for testing purposes" from Nov 3, 2022, leads to the following Smatch static checker warning: net/rxrpc/rxperf.c:337 rxperf_deliver_to_call() error: uninitialized symbol 'ret'. Fix this by initialising ret to 0. The value is only used for tracing purposes in the rxperf server. Fixes: 75bfdbf2fca3 ("rxrpc: Implement an in-kernel rxperf server for testing purposes") Reported-by: Dan Carpenter <error27@gmail.com> Signed-off-by: David Howells <dhowells@redhat.com> cc: Marc Dionne <marc.dionne@auristor.com> cc: linux-afs@lists.infradead.org Link: http://lists.infradead.org/pipermail/linux-afs/2022-December/006124.html [1] Signed-off-by: David S. Miller <davem@davemloft.net>
2022-12-19rxrpc: Fix I/O thread stopDavid Howells
The rxrpc I/O thread checks to see if there's any work it needs to do, and if not, checks kthread_should_stop() before scheduling, and if it should stop, breaks out of the loop and tries to clean up and exit. This can, however, race with socket destruction, wherein outstanding calls are aborted and released from the socket and then the socket unuses the local endpoint, causing kthread_stop() to be issued. The abort is deferred to the I/O thread and the event can by issued between the I/O thread checking if there's any work to be done (such as processing call aborts) and the stop being seen. This results in the I/O thread stopping processing of events whilst call cleanup events are still outstanding, leading to connections or other objects still being around and uncleaned up, which can result in assertions being triggered, e.g.: rxrpc: AF_RXRPC: Leaked client conn 00000000e8009865 {2} ------------[ cut here ]------------ kernel BUG at net/rxrpc/conn_client.c:64! Fix this by retrieving the kthread_should_stop() indication, then checking to see if there's more work to do, and going back round the loop if there is, and breaking out of the loop only if there wasn't. This was triggered by a syzbot test that produced some other symptom[1]. Fixes: a275da62e8c1 ("rxrpc: Create a per-local endpoint receive queue and I/O thread") Signed-off-by: David Howells <dhowells@redhat.com> cc: Marc Dionne <marc.dionne@auristor.com> cc: linux-afs@lists.infradead.org Link: https://lore.kernel.org/r/0000000000002b4a9f05ef2b616f@google.com/ [1] Signed-off-by: David S. Miller <davem@davemloft.net>
2022-12-19rxrpc: Fix switched parameters in peer tracingDavid Howells
Fix the switched parameters on rxrpc_alloc_peer() and rxrpc_get_peer(). The ref argument and the why argument got mixed. Fixes: 47c810a79844 ("rxrpc: trace: Don't use __builtin_return_address for rxrpc_peer tracing") Signed-off-by: David Howells <dhowells@redhat.com> cc: Marc Dionne <marc.dionne@auristor.com> cc: linux-afs@lists.infradead.org Signed-off-by: David S. Miller <davem@davemloft.net>
2022-12-19rxrpc: Fix locking issues in rxrpc_put_peer_locked()David Howells
Now that rxrpc_put_local() may call kthread_stop(), it can't be called under spinlock as it might sleep. This can cause a problem in the peer keepalive code in rxrpc as it tries to avoid dropping the peer_hash_lock from the point it needs to re-add peer->keepalive_link to going round the loop again in rxrpc_peer_keepalive_dispatch(). Fix this by just dropping the lock when we don't need it and accepting that we'll have to take it again. This code is only called about every 20s for each peer, so not very often. This allows rxrpc_put_peer_unlocked() to be removed also. If triggered, this bug produces an oops like the following, as reproduced by a syzbot reproducer for a different oops[1]: BUG: sleeping function called from invalid context at kernel/sched/completion.c:101 ... RCU nest depth: 0, expected: 0 3 locks held by kworker/u9:0/50: #0: ffff88810e74a138 ((wq_completion)krxrpcd){+.+.}-{0:0}, at: process_one_work+0x294/0x636 #1: ffff8881013a7e20 ((work_completion)(&rxnet->peer_keepalive_work)){+.+.}-{0:0}, at: process_one_work+0x294/0x636 #2: ffff88817d366390 (&rxnet->peer_hash_lock){+.+.}-{2:2}, at: rxrpc_peer_keepalive_dispatch+0x2bd/0x35f ... Call Trace: <TASK> dump_stack_lvl+0x4c/0x5f __might_resched+0x2cf/0x2f2 __wait_for_common+0x87/0x1e8 kthread_stop+0x14d/0x255 rxrpc_peer_keepalive_dispatch+0x333/0x35f rxrpc_peer_keepalive_worker+0x2e9/0x449 process_one_work+0x3c1/0x636 worker_thread+0x25f/0x359 kthread+0x1a6/0x1b5 ret_from_fork+0x1f/0x30 Fixes: a275da62e8c1 ("rxrpc: Create a per-local endpoint receive queue and I/O thread") Signed-off-by: David Howells <dhowells@redhat.com> cc: Marc Dionne <marc.dionne@auristor.com> cc: linux-afs@lists.infradead.org Link: https://lore.kernel.org/r/0000000000002b4a9f05ef2b616f@google.com/ [1] Signed-off-by: David S. Miller <davem@davemloft.net>
2022-12-19rxrpc: Fix I/O thread startup getting skippedDavid Howells
When starting a kthread, the __kthread_create_on_node() function, as called from kthread_run(), waits for a completion to indicate that the task_struct (or failure state) of the new kernel thread is available before continuing. This does not wait, however, for the thread function to be invoked and, indeed, will skip it if kthread_stop() gets called before it gets there. If this happens, though, kthread_run() will have returned successfully, indicating that the thread was started and returning the task_struct pointer. The actual error indication is returned by kthread_stop(). Note that this is ambiguous, as the caller cannot tell whether the -EINTR error code came from kthread() or from the thread function. This was encountered in the new rxrpc I/O thread, where if the system is being pounded hard by, say, syzbot, the check of KTHREAD_SHOULD_STOP can be delayed long enough for kthread_stop() to get called when rxrpc releases a socket - and this causes an oops because the I/O thread function doesn't get started and thus doesn't remove the rxrpc_local struct from the local_endpoints list. Fix this by using a completion to wait for the thread to actually enter rxrpc_io_thread(). This makes sure the thread can't be prematurely stopped and makes sure the relied-upon cleanup is done. Fixes: a275da62e8c1 ("rxrpc: Create a per-local endpoint receive queue and I/O thread") Reported-by: syzbot+3538a6a72efa8b059c38@syzkaller.appspotmail.com Signed-off-by: David Howells <dhowells@redhat.com> cc: Marc Dionne <marc.dionne@auristor.com> cc: Hillf Danton <hdanton@sina.com> Link: https://lore.kernel.org/r/000000000000229f1505ef2b6159@google.com/ Signed-off-by: David S. Miller <davem@davemloft.net>
2022-12-19rxrpc: Fix NULL deref in rxrpc_unuse_local()David Howells
Fix rxrpc_unuse_local() to get the debug_id *after* checking to see if local is NULL. Fixes: a2cf3264f331 ("rxrpc: Fold __rxrpc_unuse_local() into rxrpc_unuse_local()") Reported-by: syzbot+3538a6a72efa8b059c38@syzkaller.appspotmail.com Signed-off-by: David Howells <dhowells@redhat.com> Tested-by: syzbot+3538a6a72efa8b059c38@syzkaller.appspotmail.com cc: Marc Dionne <marc.dionne@auristor.com> cc: linux-afs@lists.infradead.org Signed-off-by: David S. Miller <davem@davemloft.net>
2022-12-19rxrpc: Fix security setting propagationDavid Howells
Fix the propagation of the security settings from sendmsg to the rxrpc_call struct. Fixes: f3441d4125fc ("rxrpc: Copy client call parameters into rxrpc_call earlier") Signed-off-by: David Howells <dhowells@redhat.com> cc: Marc Dionne <marc.dionne@auristor.com> cc: linux-afs@lists.infradead.org Signed-off-by: David S. Miller <davem@davemloft.net>
2022-12-19rxrpc: Fix missing unlock in rxrpc_do_sendmsg()David Howells
One of the error paths in rxrpc_do_sendmsg() doesn't unlock the call mutex before returning. Fix it to do this. Note that this still doesn't get rid of the checker warning: ../net/rxrpc/sendmsg.c:617:5: warning: context imbalance in 'rxrpc_do_sendmsg' - wrong count at exit I think the interplay between the socket lock and the call's user_mutex may be too complicated for checker to analyse, especially as rxrpc_new_client_call_for_sendmsg(), which it calls, returns with the call's user_mutex if successful but unconditionally drops the socket lock. Fixes: e754eba685aa ("rxrpc: Provide a cmsg to specify the amount of Tx data for a call") Signed-off-by: David Howells <dhowells@redhat.com> cc: Marc Dionne <marc.dionne@auristor.com> cc: linux-afs@lists.infradead.org Signed-off-by: David S. Miller <davem@davemloft.net>
2022-12-01rxrpc: Transmit ACKs at the point of generationDavid Howells
For ACKs generated inside the I/O thread, transmit the ACK at the point of generation. Where the ACK is generated outside of the I/O thread, it's offloaded to the I/O thread to transmit it. Signed-off-by: David Howells <dhowells@redhat.com> cc: Marc Dionne <marc.dionne@auristor.com> cc: linux-afs@lists.infradead.org
2022-12-01rxrpc: Fold __rxrpc_unuse_local() into rxrpc_unuse_local()David Howells
Fold __rxrpc_unuse_local() into rxrpc_unuse_local() as the latter is now the only user of the former. Signed-off-by: David Howells <dhowells@redhat.com> cc: Marc Dionne <marc.dionne@auristor.com> cc: linux-afs@lists.infradead.org
2022-12-01rxrpc: Move the cwnd degradation after transmitting packetsDavid Howells
When we've gone for >1RTT without transmitting a packet, we should reduce the ssthresh and cut the cwnd by half (as suggested in RFC2861 sec 3.1). However, we may receive ACK packets in a batch and the first of these may cut the cwnd, preventing further transmission, and each subsequent one cuts the cwnd yet further, reducing it to the floor and killing performance. Fix this by moving the cwnd reset to after doing the transmission and resetting the base time such that we don't cut the cwnd by half again for at least another RTT. Signed-off-by: David Howells <dhowells@redhat.com> cc: Marc Dionne <marc.dionne@auristor.com> cc: linux-afs@lists.infradead.org
2022-12-01rxrpc: Trace/count transmission underflows and cwnd resetsDavid Howells
Add a tracepoint to log when a cwnd reset occurs due to lack of transmission on a call. Add stat counters to count transmission underflows (ie. when we have tx window space, but sendmsg doesn't manage to keep up), cwnd resets and transmission failures. Signed-off-by: David Howells <dhowells@redhat.com> cc: Marc Dionne <marc.dionne@auristor.com> cc: linux-afs@lists.infradead.org
2022-12-01rxrpc: Remove the _bh annotation from all the spinlocksDavid Howells
None of the spinlocks in rxrpc need a _bh annotation now as the RCU callback routines no longer take spinlocks and the bulk of the packet wrangling code is now run in the I/O thread, not softirq context. Signed-off-by: David Howells <dhowells@redhat.com> cc: Marc Dionne <marc.dionne@auristor.com> cc: linux-afs@lists.infradead.org
2022-12-01rxrpc: Make the I/O thread take over the call and local processor workDavid Howells
Move the functions from the call->processor and local->processor work items into the domain of the I/O thread. The call event processor, now called from the I/O thread, then takes over the job of cranking the call state machine, processing incoming packets and transmitting DATA, ACK and ABORT packets. In a future patch, rxrpc_send_ACK() will transmit the ACK on the spot rather than queuing it for later transmission. The call event processor becomes purely received-skb driven. It only transmits things in response to events. We use "pokes" to queue a dummy skb to make it do things like start/resume transmitting data. Timer expiry also results in pokes. The connection event processor, becomes similar, though crypto events, such as dealing with CHALLENGE and RESPONSE packets is offloaded to a work item to avoid doing crypto in the I/O thread. The local event processor is removed and VERSION response packets are generated directly from the packet parser. Similarly, ABORTs generated in response to protocol errors will be transmitted immediately rather than being pushed onto a queue for later transmission. Changes: ======== ver #2) - Fix a couple of introduced lock context imbalances. Signed-off-by: David Howells <dhowells@redhat.com> cc: Marc Dionne <marc.dionne@auristor.com> cc: linux-afs@lists.infradead.org
2022-12-01rxrpc: Extract the peer address from an incoming packet earlierDavid Howells
Extract the peer address from an incoming packet earlier, at the beginning of rxrpc_input_packet() and thence pass a pointer to it to various functions that use it as part of the lookup rather than doing it on several separate paths. Signed-off-by: David Howells <dhowells@redhat.com> cc: Marc Dionne <marc.dionne@auristor.com> cc: linux-afs@lists.infradead.org
2022-12-01rxrpc: Reduce the use of RCU in packet inputDavid Howells
Shrink the region of rxrpc_input_packet() that is covered by the RCU read lock so that it only covers the connection and call lookup. This means that the bits now outside of that can call sleepable functions such as kmalloc and sendmsg. Also take a ref on the conn or call we're going to use before we drop the RCU read lock. Signed-off-by: David Howells <dhowells@redhat.com> cc: Marc Dionne <marc.dionne@auristor.com> cc: linux-afs@lists.infradead.org
2022-12-01rxrpc: Simplify skbuff accounting in receive pathDavid Howells
A received skbuff needs a ref when it gets put on a call data queue or conn packet queue, and rxrpc_input_packet() and co. jump through a lot of hoops to avoid double-dropping the skbuff ref so that we can avoid getting a ref when we queue the packet. Change this so that the skbuff ref is unconditionally dropped by the caller of rxrpc_input_packet(). An additional ref is then taken on the packet if it is pushed onto a queue. Signed-off-by: David Howells <dhowells@redhat.com> cc: Marc Dionne <marc.dionne@auristor.com> cc: linux-afs@lists.infradead.org
2022-12-01rxrpc: Remove RCU from peer->error_targets listDavid Howells
Remove the RCU requirements from the peer's list of error targets so that the error distributor can call sleeping functions. Signed-off-by: David Howells <dhowells@redhat.com> cc: Marc Dionne <marc.dionne@auristor.com> cc: linux-afs@lists.infradead.org
2022-12-01rxrpc: Move DATA transmission into call processor work itemDavid Howells
Move DATA transmission into the call processor work item. In a future patch, this will be called from the I/O thread rather than being itsown work item. This will allow DATA transmission to be driven directly by incoming ACKs, pokes and timers as those are processed. The Tx queue is also split: The queue of packets prepared by sendmsg is now places in call->tx_sendmsg and the packet dispatcher decants the packets into call->tx_buffer as space becomes available in the transmission window. This allows sendmsg to run ahead of the available space to try and prevent an underflow in transmission. Signed-off-by: David Howells <dhowells@redhat.com> cc: Marc Dionne <marc.dionne@auristor.com> cc: linux-afs@lists.infradead.org
2022-12-01rxrpc: Copy client call parameters into rxrpc_call earlierDavid Howells
Copy client call parameters into rxrpc_call earlier so that that can be used to convey them to the connection code - which can then be offloaded to the I/O thread. Signed-off-by: David Howells <dhowells@redhat.com> cc: Marc Dionne <marc.dionne@auristor.com> cc: linux-afs@lists.infradead.org
2022-12-01rxrpc: Implement a mechanism to send an event notification to a callDavid Howells
Provide a means by which an event notification can be sent to a call such that the I/O thread can process it rather than it being done in a separate workqueue. This will allow a lot of locking to be removed. Signed-off-by: David Howells <dhowells@redhat.com> cc: Marc Dionne <marc.dionne@auristor.com> cc: linux-afs@lists.infradead.org
2022-12-01rxrpc: Don't use sk->sk_receive_queue.lock to guard socket state changesDavid Howells
Don't use sk->sk_receive_queue.lock to guard socket state changes as the socket mutex is sufficient. Signed-off-by: David Howells <dhowells@redhat.com> cc: Marc Dionne <marc.dionne@auristor.com> cc: linux-afs@lists.infradead.org
2022-12-01rxrpc: Remove call->input_lockDavid Howells
Remove call->input_lock as it was only necessary to serialise access to the state stored in the rxrpc_call struct by simultaneous softirq handlers presenting received packets. They now dump the packets in a queue and a single process-context handler now processes them. Signed-off-by: David Howells <dhowells@redhat.com> cc: Marc Dionne <marc.dionne@auristor.com> cc: linux-afs@lists.infradead.org
2022-12-01rxrpc: Move error processing into the local endpoint I/O threadDavid Howells
Move the processing of error packets into the local endpoint I/O thread, leaving the handover from UDP to merely transfer them into the local endpoint queue. Signed-off-by: David Howells <dhowells@redhat.com> cc: Marc Dionne <marc.dionne@auristor.com> cc: linux-afs@lists.infradead.org
2022-12-01rxrpc: Move packet reception processing into I/O threadDavid Howells
Split the packet input handler to make the softirq side just dump the received packet into the local endpoint receive queue and then call the remainder of the input function from the I/O thread. Signed-off-by: David Howells <dhowells@redhat.com> cc: Marc Dionne <marc.dionne@auristor.com> cc: linux-afs@lists.infradead.org