From 466a7b8cab7847bcee35aff5c35ed79361cde427 Mon Sep 17 00:00:00 2001
From: Sergey Matveev <stargrave@stargrave.org>
Date: Thu, 22 Apr 2021 15:48:41 +0300
Subject: [PATCH] Fixed possible data race

---
 doc/news.ru.texi    | 10 ++++++++++
 doc/news.texi       |  9 +++++++++
 ports/nncp/Makefile |  2 +-
 src/nncp.go         |  2 +-
 src/sp.go           | 16 +++++++++++++---
 5 files changed, 34 insertions(+), 5 deletions(-)

diff --git a/doc/news.ru.texi b/doc/news.ru.texi
index ea1c700..aa4f62f 100644
--- a/doc/news.ru.texi
+++ b/doc/news.ru.texi
@@ -1,6 +1,16 @@
 @node Новости
 @section Новости
 
+@node Релиз 6.4.0
+@subsection Релиз 6.4.0
+@itemize
+
+@item
+Исправлена возможная гонка в online протоколе, приводящая к падению
+программы.
+
+@end itemize
+
 @node Релиз 6.3.0
 @subsection Релиз 6.3.0
 @itemize
diff --git a/doc/news.texi b/doc/news.texi
index 87be652..67340e2 100644
--- a/doc/news.texi
+++ b/doc/news.texi
@@ -3,6 +3,15 @@
 
 See also this page @ref{Новости, on russian}.
 
+@node Release 6.4.0
+@section Release 6.4.0
+@itemize
+
+@item
+Fixed possible race in online protocol, that lead to panic.
+
+@end itemize
+
 @node Release 6.3.0
 @section Release 6.3.0
 @itemize
diff --git a/ports/nncp/Makefile b/ports/nncp/Makefile
index bb053c3..c398830 100644
--- a/ports/nncp/Makefile
+++ b/ports/nncp/Makefile
@@ -1,5 +1,5 @@
 PORTNAME=	nncp
-DISTVERSION=	6.3.0
+DISTVERSION=	6.4.0
 CATEGORIES=	net
 MASTER_SITES=	http://www.nncpgo.org/download/
 
diff --git a/src/nncp.go b/src/nncp.go
index 12edaa4..7c1b7c5 100644
--- a/src/nncp.go
+++ b/src/nncp.go
@@ -40,7 +40,7 @@ along with this program.  If not, see <http://www.gnu.org/licenses/>.`
 const Base32Encoded32Len = 52
 
 var (
-	Version string = "6.3.0"
+	Version string = "6.4.0"
 
 	Base32Codec *base32.Encoding = base32.StdEncoding.WithPadding(base32.NoPadding)
 )
diff --git a/src/sp.go b/src/sp.go
index e6e4900..6d31375 100644
--- a/src/sp.go
+++ b/src/sp.go
@@ -233,6 +233,7 @@ type SPState struct {
 	onlyPkts       map[[32]byte]bool
 	writeSPBuf     bytes.Buffer
 	fds            map[string]FdAndFullSize
+	fdsLock        sync.RWMutex
 	fileHashers    map[string]*HasherAndOffset
 	checkerQueues  SPCheckerQueues
 	sync.RWMutex
@@ -669,11 +670,12 @@ func (state *SPState) StartR(conn ConnDeadlined) error {
 }
 
 func (state *SPState) closeFd(pth string) {
-	s, exists := state.fds[pth]
-	delete(state.fds, pth)
-	if exists {
+	state.fdsLock.Lock()
+	if s, exists := state.fds[pth]; exists {
+		delete(state.fds, pth)
 		s.fd.Close()
 	}
+	state.fdsLock.Unlock()
 }
 
 func (state *SPState) StartWorkers(
@@ -914,7 +916,9 @@ func (state *SPState) StartWorkers(
 					string(TTx),
 					Base32Codec.EncodeToString(freq.Hash[:]),
 				)
+				state.fdsLock.RLock()
 				fdAndFullSize, exists := state.fds[pth]
+				state.fdsLock.RUnlock()
 				if !exists {
 					fd, err := os.Open(pth)
 					if err != nil {
@@ -931,7 +935,9 @@ func (state *SPState) StartWorkers(
 						return
 					}
 					fdAndFullSize = FdAndFullSize{fd: fd, fullSize: fi.Size()}
+					state.fdsLock.Lock()
 					state.fds[pth] = fdAndFullSize
+					state.fdsLock.Unlock()
 				}
 				fd := fdAndFullSize.fd
 				fullSize := fdAndFullSize.fullSize
@@ -1352,7 +1358,9 @@ func (state *SPState) ProcessSP(payload []byte) ([][]byte, error) {
 			state.Ctx.LogD("sp-file-open", lesp, func(les LEs) string {
 				return logMsg(les) + ": opening part"
 			})
+			state.fdsLock.RLock()
 			fdAndFullSize, exists := state.fds[filePathPart]
+			state.fdsLock.RUnlock()
 			var fd *os.File
 			if exists {
 				fd = fdAndFullSize.fd
@@ -1368,7 +1376,9 @@ func (state *SPState) ProcessSP(payload []byte) ([][]byte, error) {
 					})
 					return nil, err
 				}
+				state.fdsLock.Lock()
 				state.fds[filePathPart] = FdAndFullSize{fd: fd}
+				state.fdsLock.Unlock()
 				if file.Offset == 0 {
 					h, err := blake2b.New256(nil)
 					if err != nil {
-- 
2.44.0