Panic when using latest version of gomemcached / go-couchbase

[tleyden]

From #1572

I noticed the following panic when running the functional tests via py.test -s -k “test_users_channels"

panic: runtime error: slice bounds out of range

goroutine 42 [running]:
github.com/couchbase/gomemcached.(*MCRequest).Receive(0xc820423280, 0x7fb2c5088550, 0xc820024e08, 0xc820437d40, 0x18, 0x18, 0x0, 0x0, 0x0)
    /workspace/src/github.com/couchbase/gomemcached/mc_req.go:181 +0xbcc
github.com/couchbase/gomemcached/client.(*Client).runFeed(0xc820429ad0, 0xc82043b140, 0xc820437d20)
    /workspace/src/github.com/couchbase/gomemcached/client/tap_feed.go:270 +0x149
created by github.com/couchbase/gomemcached/client.(*Client).StartTapFeed
    /workspace/src/github.com/couchbase/gomemcached/client/tap_feed.go:251 +0x428

Note: there were also errors when running the same functional tests against the master branch of Sync Gateway, however I didn't notice any panics (which doesn't mean there wasn't any). Having trouble interpreting the functional test output from that run.

#1572 (comment)

#1572 (comment)

[adamcfraser]

Looked into this - it looks like a regression in gomemcached after the changes made in couchbase/gomemcached@f4caed2.

Sent a note to @ysui6888 to try to get more details - it looks to me like an incorrect version of bodyLen is being used to calculate valueLen, and that's causing the slice out of range panic.

[adamcfraser]

This has been fixed in go-couchbase.