From 758d078fd5ab423d00f5a46028139c1d13983120 Mon Sep 17 00:00:00 2001 From: Todd Neal Date: Tue, 11 Apr 2017 18:52:05 -0500 Subject: [PATCH] plugin: resolve random crash when calling exported functions open modified the plugin symbols map while ranging over it. This is normally harmless, except that the operations performed were not idempotent leading to function pointers being corrupted. Fixes #19269 Change-Id: I4b6eb1d45567161412e4a34b41f1ebf647bcc942 Reviewed-on: https://go-review.googlesource.com/40431 Run-TryBot: Todd Neal TryBot-Result: Gobot Gobot Reviewed-by: David Crawshaw --- src/plugin/plugin_dlopen.go | 9 ++++++--- 1 file changed, 6 insertions(+), 3 deletions(-) diff --git a/src/plugin/plugin_dlopen.go b/src/plugin/plugin_dlopen.go index c5b0a4721c..72e219e337 100644 --- a/src/plugin/plugin_dlopen.go +++ b/src/plugin/plugin_dlopen.go @@ -82,7 +82,6 @@ func open(name string) (*Plugin, error) { p := &Plugin{ pluginpath: pluginpath, loaded: make(chan struct{}), - syms: syms, } plugins[filepath] = p pluginsMu.Unlock() @@ -97,13 +96,13 @@ func open(name string) (*Plugin, error) { } // Fill out the value of each plugin symbol. + updatedSyms := map[string]interface{}{} for symName, sym := range syms { isFunc := symName[0] == '.' if isFunc { delete(syms, symName) symName = symName[1:] } - cname := C.CString(pluginpath + "." + symName) p := C.pluginLookup(h, cname, &cErr) C.free(unsafe.Pointer(cname)) @@ -116,8 +115,12 @@ func open(name string) (*Plugin, error) { } else { (*valp)[1] = p } - syms[symName] = sym + // we can't add to syms during iteration as we'll end up processing + // some symbols twice with the inability to tell if the symbol is a function + updatedSyms[symName] = sym } + p.syms = updatedSyms + close(p.loaded) return p, nil } -- 2.48.1