kernel/git/stable/linux.git/net/rxrpc/sendmsg.c, branch linux-4.19.y

rxrpc: Fix hard call timeout units

2023-05-17T09:13:24+00:00

[ Upstream commit 0d098d83c5d9e107b2df7f5e11f81492f56d2fe7 ] 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 Signed-off-by: Sasha Levin

rxrpc: Fix missing unlock in rxrpc_do_sendmsg()

2023-01-18T10:30:33+00:00

[ Upstream commit 4feb2c44629e6f9b459b41a5a60491069d346a95 ] 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 cc: Marc Dionne cc: linux-afs@lists.infradead.org Signed-off-by: David S. Miller Signed-off-by: Sasha Levin

rxrpc: Return an error to sendmsg if call failed

2022-06-14T14:59:17+00:00

[ Upstream commit 4ba68c5192554876bd8c3afd904e3064d2915341 ] If at the end of rxrpc sendmsg() or rxrpc_kernel_send_data() the call that was being given data was aborted remotely or otherwise failed, return an error rather than returning the amount of data buffered for transmission. The call (presumably) did not complete, so there's not much point continuing with it. AF_RXRPC considers it "complete" and so will be unwilling to do anything else with it - and won't send a notification for it, deeming the return from sendmsg sufficient. Not returning an error causes afs to incorrectly handle a StoreData operation that gets interrupted by a change of address due to NAT reconfiguration. This doesn't normally affect most operations since their request parameters tend to fit into a single UDP packet and afs_make_call() returns before the server responds; StoreData is different as it involves transmission of a lot of data. This can be triggered on a client by doing something like: dd if=/dev/zero of=/afs/example.com/foo bs=1M count=512 at one prompt, and then changing the network address at another prompt, e.g.: ifconfig enp6s0 inet 192.168.6.2 && route add 192.168.6.1 dev enp6s0 Tracing packets on an Auristor fileserver looks something like: 192.168.6.1 -> 192.168.6.3 RX 107 ACK Idle Seq: 0 Call: 4 Source Port: 7000 Destination Port: 7001 192.168.6.3 -> 192.168.6.1 AFS (RX) 1482 FS Request: Unknown(64538) (64538) 192.168.6.3 -> 192.168.6.1 AFS (RX) 1482 FS Request: Unknown(64538) (64538) 192.168.6.1 -> 192.168.6.3 RX 107 ACK Idle Seq: 0 Call: 4 Source Port: 7000 Destination Port: 7001 192.168.6.2 -> 192.168.6.1 AFS (RX) 1482 FS Request: Unknown(0) (0) 192.168.6.2 -> 192.168.6.1 AFS (RX) 1482 FS Request: Unknown(0) (0) 192.168.6.1 -> 192.168.6.2 RX 107 ACK Exceeds Window Seq: 0 Call: 4 Source Port: 7000 Destination Port: 7001 192.168.6.1 -> 192.168.6.2 RX 74 ABORT Seq: 0 Call: 4 Source Port: 7000 Destination Port: 7001 192.168.6.1 -> 192.168.6.2 RX 74 ABORT Seq: 29321 Call: 4 Source Port: 7000 Destination Port: 7001 The Auristor fileserver logs code -453 (RXGEN_SS_UNMARSHAL), but the abort code received by kafs is -5 (RX_PROTOCOL_ERROR) as the rx layer sees the condition and generates an abort first and the unmarshal error is a consequence of that at the application layer. Reported-by: Marc Dionne Signed-off-by: David Howells cc: linux-afs@lists.infradead.org Link: http://lists.infradead.org/pipermail/linux-afs/2021-December/004810.html # v1 Signed-off-by: David S. Miller Signed-off-by: Sasha Levin

rxrpc: Fix race between recvmsg and sendmsg on immediate call failure

2020-08-11T13:32:35+00:00

[ Upstream commit 65550098c1c4db528400c73acf3e46bfa78d9264 ] There's a race between rxrpc_sendmsg setting up a call, but then failing to send anything on it due to an error, and recvmsg() seeing the call completion occur and trying to return the state to the user. An assertion fails in rxrpc_recvmsg() because the call has already been released from the socket and is about to be released again as recvmsg deals with it. (The recvmsg_q queue on the socket holds a ref, so there's no problem with use-after-free.) We also have to be careful not to end up reporting an error twice, in such a way that both returns indicate to userspace that the user ID supplied with the call is no longer in use - which could cause the client to malfunction if it recycles the user ID fast enough. Fix this by the following means: (1) When sendmsg() creates a call after the point that the call has been successfully added to the socket, don't return any errors through sendmsg(), but rather complete the call and let recvmsg() retrieve them. Make sendmsg() return 0 at this point. Further calls to sendmsg() for that call will fail with ESHUTDOWN. Note that at this point, we haven't send any packets yet, so the server doesn't yet know about the call. (2) If sendmsg() returns an error when it was expected to create a new call, it means that the user ID wasn't used. (3) Mark the call disconnected before marking it completed to prevent an oops in rxrpc_release_call(). (4) recvmsg() will then retrieve the error and set MSG_EOR to indicate that the user ID is no longer known by the kernel. An oops like the following is produced: kernel BUG at net/rxrpc/recvmsg.c:605! ... RIP: 0010:rxrpc_recvmsg+0x256/0x5ae ... Call Trace: ? __init_waitqueue_head+0x2f/0x2f ____sys_recvmsg+0x8a/0x148 ? import_iovec+0x69/0x9c ? copy_msghdr_from_user+0x5c/0x86 ___sys_recvmsg+0x72/0xaa ? __fget_files+0x22/0x57 ? __fget_light+0x46/0x51 ? fdget+0x9/0x1b do_recvmmsg+0x15e/0x232 ? _raw_spin_unlock+0xa/0xb ? vtime_delta+0xf/0x25 __x64_sys_recvmmsg+0x2c/0x2f do_syscall_64+0x4c/0x78 entry_SYSCALL_64_after_hwframe+0x44/0xa9 Fixes: 357f5ef64628 ("rxrpc: Call rxrpc_release_call() on error in rxrpc_new_client_call()") Reported-by: syzbot+b54969381df354936d96@syzkaller.appspotmail.com Signed-off-by: David Howells Reviewed-by: Marc Dionne Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

rxrpc: Fix sendmsg() returning EPIPE due to recvmsg() returning ENODATA

2020-07-31T16:37:48+00:00

[ Upstream commit 639f181f0ee20d3249dbc55f740f0167267180f0 ] rxrpc_sendmsg() returns EPIPE if there's an outstanding error, such as if rxrpc_recvmsg() indicating ENODATA if there's nothing for it to read. Change rxrpc_recvmsg() to return EAGAIN instead if there's nothing to read as this particular error doesn't get stored in ->sk_err by the networking core. Also change rxrpc_sendmsg() so that it doesn't fail with delayed receive errors (there's no way for it to report which call, if any, the error was caused by). Fixes: 17926a79320a ("[AF_RXRPC]: Provide secure RxRPC sockets for use by userspace and kernel both") Signed-off-by: David Howells Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

rxrpc: Fix sendmsg(MSG_WAITALL) handling

2020-04-13T08:45:04+00:00

commit 498b577660f08cef5d9e78e0ed6dcd4c0939e98c upstream. Fix the handling of sendmsg() with MSG_WAITALL for userspace to round the timeout for when a signal occurs up to at least two jiffies as a 1 jiffy timeout may end up being effectively 0 if jiffies wraps at the wrong time. Fixes: bc5e3a546d55 ("rxrpc: Use MSG_WAITALL to tell sendmsg() to temporarily ignore signals") Signed-off-by: David Howells Signed-off-by: Greg Kroah-Hartman

rxrpc: Fix call ref leak

2019-11-06T12:06:23+00:00

commit c48fc11b69e95007109206311b0187a3090591f3 upstream. When sendmsg() finds a call to continue on with, if the call is in an inappropriate state, it doesn't release the ref it just got on that call before returning an error. This causes the following symptom to show up with kasan: BUG: KASAN: use-after-free in rxrpc_send_keepalive+0x8a2/0x940 net/rxrpc/output.c:635 Read of size 8 at addr ffff888064219698 by task kworker/0:3/11077 where line 635 is: whdr.epoch = htonl(peer->local->rxnet->epoch); The local endpoint (which cannot be pinned by the call) has been released, but not the peer (which is pinned by the call). Fix this by releasing the call in the error path. Fixes: 37411cad633f ("rxrpc: Fix potential NULL-pointer exception") Reported-by: syzbot+d850c266e3df14da1d31@syzkaller.appspotmail.com Signed-off-by: David Howells Signed-off-by: Greg Kroah-Hartman

rxrpc: Fix the lack of notification when sendmsg() fails on a DATA packet

2019-08-29T06:28:35+00:00

[ Upstream commit c69565ee6681e151e2bb80502930a16e04b553d1 ] Fix the fact that a notification isn't sent to the recvmsg side to indicate a call failed when sendmsg() fails to transmit a DATA packet with the error ENETUNREACH, EHOSTUNREACH or ECONNREFUSED. Without this notification, the afs client just sits there waiting for the call to complete in some manner (which it's not now going to do), which also pins the rxrpc call in place. This can be seen if the client has a scope-level IPv6 address, but not a global-level IPv6 address, and we try and transmit an operation to a server's IPv6 address. Looking in /proc/net/rxrpc/calls shows completed calls just sat there with an abort code of RX_USER_ABORT and an error code of -ENETUNREACH. Fixes: c54e43d752c7 ("rxrpc: Fix missing start of call timeout") Signed-off-by: David Howells Reviewed-by: Marc Dionne Reviewed-by: Jeffrey Altman Signed-off-by: Sasha Levin

rxrpc: Fix missing start of call timeout

2018-05-10T22:26:00+00:00

The expect_rx_by call timeout is supposed to be set when a call is started to indicate that we need to receive a packet by that point. This is currently put back every time we receive a packet, but it isn't started when we first send a packet. Without this, the call may wait forever if the server doesn't deign to reply. Fix this by setting the timeout upon a successful UDP sendmsg call for the first DATA packet. The timeout is initiated only for initial transmission and not for subsequent retries as we don't want the retry mechanism to extend the timeout indefinitely. Fixes: a158bdd3247b ("rxrpc: Fix call timeouts") Reported-by: Marc Dionne Signed-off-by: David Howells

rxrpc: Fix leak of rxrpc_peer objects

2018-03-30T20:05:44+00:00

When a new client call is requested, an rxrpc_conn_parameters struct object is passed in with a bunch of parameters set, such as the local endpoint to use. A pointer to the target peer record is also placed in there by rxrpc_get_client_conn() - and this is removed if and only if a new connection object is allocated. Thus it leaks if a new connection object isn't allocated. Fix this by putting any peer object attached to the rxrpc_conn_parameters object in the function that allocated it. Fixes: 19ffa01c9c45 ("rxrpc: Use structs to hold connection params and protocol info") Signed-off-by: David Howells