From 524cba2f8de57d612eee67a3fe5f672cc39f549c Mon Sep 17 00:00:00 2001 From: David Howells Date: Thu, 30 Jan 2020 21:50:36 +0000 Subject: [PATCH] rxrpc: Fix insufficient receive notification generation [ Upstream commit f71dbf2fb28489a79bde0dca1c8adfb9cdb20a6b ] In rxrpc_input_data(), rxrpc_notify_socket() is called if the base sequence number of the packet is immediately following the hard-ack point at the end of the function. However, this isn't sufficient, since the recvmsg side may have been advancing the window and then overrun the position in which we're adding - at which point rx_hard_ack >= seq0 and no notification is generated. Fix this by always generating a notification at the end of the input function. Without this, a long call may stall, possibly indefinitely. Fixes: 248f219cb8bc ("rxrpc: Rewrite the data and ack handling code") Signed-off-by: David Howells Signed-off-by: Greg Kroah-Hartman --- net/rxrpc/input.c | 6 ++---- 1 file changed, 2 insertions(+), 4 deletions(-) diff --git a/net/rxrpc/input.c b/net/rxrpc/input.c index 96d54e5..ef10fbf 100644 --- a/net/rxrpc/input.c +++ b/net/rxrpc/input.c @@ -599,10 +599,8 @@ ack: false, true, rxrpc_propose_ack_input_data); - if (seq0 == READ_ONCE(call->rx_hard_ack) + 1) { - trace_rxrpc_notify_socket(call->debug_id, serial); - rxrpc_notify_socket(call); - } + trace_rxrpc_notify_socket(call->debug_id, serial); + rxrpc_notify_socket(call); unlock: spin_unlock(&call->input_lock); -- 2.7.4