kernel/git/stable/linux.git/net/rxrpc, branch linux-5.8.y

rxrpc: Fix server keyring leak

2020-10-14T09:55:58+00:00

[ Upstream commit 38b1dc47a35ba14c3f4472138ea56d014c2d609b ] If someone calls setsockopt() twice to set a server key keyring, the first keyring is leaked. Fix it to return an error instead if the server key keyring is already set. Fixes: 17926a79320a ("[AF_RXRPC]: Provide secure RxRPC sockets for use by userspace and kernel both") Signed-off-by: David Howells Signed-off-by: Sasha Levin

rxrpc: The server keyring isn't network-namespaced

2020-10-14T09:55:58+00:00

[ Upstream commit fea99111244bae44e7d82a973744d27ea1567814 ] The keyring containing the server's tokens isn't network-namespaced, so it shouldn't be looked up with a network namespace. It is expected to be owned specifically by the server, so namespacing is unnecessary. Fixes: a58946c158a0 ("keys: Pass the network namespace into request_key mechanism") Signed-off-by: David Howells Signed-off-by: Sasha Levin

rxrpc: Fix some missing _bh annotations on locking conn->state_lock

2020-10-14T09:55:58+00:00

[ Upstream commit fa1d113a0f96f9ab7e4fe4f8825753ba1e34a9d3 ] conn->state_lock may be taken in softirq mode, but a previous patch replaced an outer lock in the response-packet event handling code, and lost the _bh from that when doing so. Fix this by applying the _bh annotation to the state_lock locking. Fixes: a1399f8bb033 ("rxrpc: Call channels should have separate call number spaces") Signed-off-by: David Howells Signed-off-by: Sasha Levin

rxrpc: Downgrade the BUG() for unsupported token type in rxrpc_read()

2020-10-14T09:55:58+00:00

[ Upstream commit 9a059cd5ca7d9c5c4ca5a6e755cf72f230176b6a ] If rxrpc_read() (which allows KEYCTL_READ to read a key), sees a token of a type it doesn't recognise, it can BUG in a couple of places, which is unnecessary as it can easily get back to userspace. Fix this to print an error message instead. Fixes: 99455153d067 ("RxRPC: Parse security index 5 keys (Kerberos 5)") Signed-off-by: David Howells Signed-off-by: Sasha Levin

rxrpc: Fix rxkad token xdr encoding

2020-10-14T09:55:57+00:00

[ Upstream commit 56305118e05b2db8d0395bba640ac9a3aee92624 ] The session key should be encoded with just the 8 data bytes and no length; ENCODE_DATA precedes it with a 4 byte length, which confuses some existing tools that try to parse this format. Add an ENCODE_BYTES macro that does not include a length, and use it for the key. Also adjust the expected length. Note that commit 774521f353e1d ("rxrpc: Fix an assertion in rxrpc_read()") had fixed a BUG by changing the length rather than fixing the encoding. The original length was correct. Fixes: 99455153d067 ("RxRPC: Parse security index 5 keys (Kerberos 5)") Signed-off-by: Marc Dionne Signed-off-by: David Howells Signed-off-by: Sasha Levin

rxrpc: Make rxrpc_kernel_get_srtt() indicate validity

2020-09-09T17:14:14+00:00

[ Upstream commit 1d4adfaf65746203861c72d9d78de349eb97d528 ] Fix rxrpc_kernel_get_srtt() to indicate the validity of the returned smoothed RTT. If we haven't had any valid samples yet, the SRTT isn't useful. Fixes: c410bf01933e ("rxrpc: Fix the excessive initial retransmission timeout") Signed-off-by: David Howells Signed-off-by: Sasha Levin

rxrpc: Fix loss of RTT samples due to interposed ACK

2020-09-09T17:14:13+00:00

[ Upstream commit 4700c4d80b7bb171f6996016ef121e1508860b42 ] The Rx protocol has a mechanism to help generate RTT samples that works by a client transmitting a REQUESTED-type ACK when it receives a DATA packet that has the REQUEST_ACK flag set. The peer, however, may interpose other ACKs before transmitting the REQUESTED-ACK, as can be seen in the following trace excerpt: rxrpc_tx_data: c=00000044 DATA d0b5ece8:00000001 00000001 q=00000001 fl=07 rxrpc_rx_ack: c=00000044 00000001 PNG r=00000000 f=00000002 p=00000000 n=0 rxrpc_rx_ack: c=00000044 00000002 REQ r=00000001 f=00000002 p=00000001 n=0 ... DATA packet 1 (q=xx) has REQUEST_ACK set (bit 1 of fl=xx). The incoming ping (labelled PNG) hard-acks the request DATA packet (f=xx exceeds the sequence number of the DATA packet), causing it to be discarded from the Tx ring. The ACK that was requested (labelled REQ, r=xx references the serial of the DATA packet) comes after the ping, but the sk_buff holding the timestamp has gone and the RTT sample is lost. This is particularly noticeable on RPC calls used to probe the service offered by the peer. A lot of peers end up with an unknown RTT because we only ever sent a single RPC. This confuses the server rotation algorithm. Fix this by caching the information about the outgoing packet in RTT calculations in the rxrpc_call struct rather than looking in the Tx ring. A four-deep buffer is maintained and both REQUEST_ACK-flagged DATA and PING-ACK transmissions are recorded in there. When the appropriate response ACK is received, the buffer is checked for a match and, if found, an RTT sample is recorded. If a received ACK refers to a packet with a later serial number than an entry in the cache, that entry is presumed lost and the entry is made available to record a new transmission. ACKs types other than REQUESTED-type and PING-type cause any matching sample to be cancelled as they don't necessarily represent a useful measurement. If there's no space in the buffer on ping/data transmission, the sample base is discarded. Fixes: 50235c4b5a2f ("rxrpc: Obtain RTT data by requesting ACKs on DATA packets") Signed-off-by: David Howells Signed-off-by: Sasha Levin

rxrpc: Keep the ACK serial in a var in rxrpc_input_ack()

2020-09-09T17:14:13+00:00

[ Upstream commit 68528d937dcd675e79973061c1a314db598162d1 ] Keep the ACK serial number in a variable in rxrpc_input_ack() as it's used frequently. Signed-off-by: David Howells Signed-off-by: Sasha Levin

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

2020-07-30T23:50:20+00:00

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

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

2020-07-21T00:47:10+00:00

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