Details
Critical Description
When the couchbase server is stopped while application is connected and accessing a bucket, the application is stopped by an abort in libcouchbase.
This happens both using versions 2.0.6 and 2.1.3 of the client.
(version 2.0.6)
(gdb) where
#0 0x0000003083c328a5 in raise () from /lib64/libc.so.6
#1 0x0000003083c34085 in abort () from /lib64/libc.so.6
#2 0x00007ffff7bca48a in lcb_purge_single_server (server=0x7f4a20, error=LCB_NETWORK_ERROR) at src/server.c:322
#3 0x00007ffff7bca67d in lcb_failout_server (server=0x7f4a20, error=LCB_NETWORK_ERROR) at src/server.c:368
#4 0x00007ffff7bbd0a2 in do_fill_input_buffer (c=0x7f4a20) at src/event.c:55
#5 0x00007ffff7bbd9e0 in do_read_data (c=0x7f4a20, allow_read=2) at src/event.c:299
#6 0x00007ffff7bbdc77 in lcb_server_event_handler (sock=33, which=2, arg=0x7f4a20) at src/event.c:387
#7 0x00007ffff7de8b44 in event_process_active (base=0x7c72f0, flags=<value optimized out>) at event.c:385
#8 event_base_loop (base=0x7c72f0, flags=<value optimized out>) at event.c:525
#9 0x000000000046ed72 in con_thr (arg=0x6f31b0) at src/store_couchbase.c:2519
#10 0x0000003084407851 in start_thread () from /lib64/libpthread.so.0
#11 0x0000003083ce890d in clone () from /lib64/libc.so.6
(gdb) frame 2
#2 0x00007ffff7bca48a in lcb_purge_single_server (server=0x7f4a20, error=LCB_NETWORK_ERROR) at src/server.c:322
322 abort();
(gdb) p req
$1 = {
request =
,
bytes = "\200\224\000\v\000\000\001\317\000\000\000\v\312\000\000\000\000\000\000\000\000\000\000"
}
The opcode 148 corresponds with CMD_GET_LOCKED, which matches one of the operations the application does.
The switch in server.c lcb_purge_single_server() seems to be missing some commands, not only the GET_LOCKED, causing the abort() in the default clause to trigger on network errors.
Also UNLOCK is not handled in the switch.
Adding the missing opcode for a locked get prevents the crash for my application:
— src/server.c.orig 2013-09-27 15:26:12.729822014 +0200
+++ src/server.c 2013-09-27 15:25:50.504008318 +0200
@@ -174,6 +174,7 @@
switch (req.request.opcode) {
case PROTOCOL_BINARY_CMD_NOOP:
break;
+ case CMD_GET_LOCKED:
case PROTOCOL_BINARY_CMD_GAT:
case PROTOCOL_BINARY_CMD_GATQ:
case PROTOCOL_BINARY_CMD_GET: