From 8a51210efca6ecd881d3336c8d7b4f6ef0ff30e2 Mon Sep 17 00:00:00 2001 From: Anton Kaliaev Date: Fri, 28 Jul 2017 11:22:48 -0400 Subject: [PATCH] [common] use temp intead of {filePath}.new The problem with {filePath}.new is that it is not safe for concurrent use! Calling this function with the same params results in the following error: ``` panic: Panicked on a Crisis: rename /root/.tendermint_test/consensus_replay_test/priv_validator.json.new /root/.tendermint_test/consensus_replay_test/priv_validator.json: no such file or directory goroutine 47860 [running]: github.com/tendermint/tendermint/vendor/github.com/tendermint/tmlibs/common.PanicCrisis(0xcba800, 0xc42152d640) /go/src/github.com/tendermint/tendermint/vendor/github.com/tendermint/tmlibs/common/errors.go:33 +0x10f github.com/tendermint/tendermint/types.(*PrivValidator).save(0xc42235f2c0) /go/src/github.com/tendermint/tendermint/types/priv_validator.go:165 +0x159 github.com/tendermint/tendermint/types.(*PrivValidator).signBytesHRS(0xc42235f2c0, 0x6, 0x0, 0xc424e88f03, 0xc429908580, 0xca, 0x155, 0x80, 0xc424e88f00, 0x7f4ecafc88d0, ...) /go/src/github.com/tendermint/tendermint/types/priv_validator.go:249 +0x2bb github.com/tendermint/tendermint/types.(*PrivValidator).SignVote(0xc42235f2c0, 0xc4228c7460, 0xf, 0xc424e88f00, 0x0, 0x0) /go/src/github.com/tendermint/tendermint/types/priv_validator.go:186 +0x1a2 github.com/tendermint/tendermint/consensus.(*ConsensusState).signVote(0xc424efd520, 0xc400000002, 0xc422d5e3c0, 0x14, 0x20, 0x1, 0xc4247b6560, 0x14, 0x20, 0x0, ...) github.com/tendermint/tendermint/consensus/_test/_obj_test/state.go:1556 +0x35e github.com/tendermint/tendermint/consensus.(*ConsensusState).signAddVote(0xc424efd520, 0x2, 0xc422d5e3c0, 0x14, 0x20, 0x1, 0xc4247b6560, 0x14, 0x20, 0xc42001b300) github.com/tendermint/tendermint/consensus/_test/_obj_test/state.go:1568 +0x200 github.com/tendermint/tendermint/consensus.(*ConsensusState).enterPrecommit(0xc424efd520, 0x6, 0x0) github.com/tendermint/tendermint/consensus/_test/_obj_test/state.go:1082 +0x13a4 github.com/tendermint/tendermint/consensus.(*ConsensusState).addVote(0xc424efd520, 0xc424e88780, 0x0, 0x0, 0x39, 0x1dc, 0x28c) github.com/tendermint/tendermint/consensus/_test/_obj_test/state.go:1477 +0x1be5 github.com/tendermint/tendermint/consensus.(*ConsensusState).tryAddVote(0xc424efd520, 0xc424e88780, 0x0, 0x0, 0xd7fb00, 0xc42152ce00) github.com/tendermint/tendermint/consensus/_test/_obj_test/state.go:1382 +0x93 github.com/tendermint/tendermint/consensus.(*ConsensusState).handleMsg(0xc424efd520, 0xcb58e0, 0xc42547feb8, 0x0, 0x0, 0x6, 0x0, 0x4, 0xed10ca07e, 0x3077bfea, ...) github.com/tendermint/tendermint/consensus/_test/_obj_test/state.go:660 +0x9fc github.com/tendermint/tendermint/consensus.(*ConsensusState).receiveRoutine(0xc424efd520, 0x0) github.com/tendermint/tendermint/consensus/_test/_obj_test/state.go:615 +0x5f5 created by github.com/tendermint/tendermint/consensus.(*ConsensusState).OnStart github.com/tendermint/tendermint/consensus/_test/_obj_test/state.go:332 +0x4a7 exit status 2 FAIL github.com/tendermint/tendermint/consensus 76.644s make: *** [test_integrations] Error 1 ``` See https://github.com/tendermint/tendermint/pull/568 --- common/os.go | 29 +++++++++++++++++++++-------- 1 file changed, 21 insertions(+), 8 deletions(-) diff --git a/common/os.go b/common/os.go index 9dc81c57..ae2ed087 100644 --- a/common/os.go +++ b/common/os.go @@ -93,9 +93,8 @@ func MustWriteFile(filePath string, contents []byte, mode os.FileMode) { } } -// Writes to newBytes to filePath. -// Guaranteed not to lose *both* oldBytes and newBytes, -// (assuming that the OS is perfect) +// WriteFileAtomic writes newBytes to temp and atomically moves to filePath +// when everything else succeeds. func WriteFileAtomic(filePath string, newBytes []byte, mode os.FileMode) error { // If a file already exists there, copy to filePath+".bak" (overwrite anything) if _, err := os.Stat(filePath); !os.IsNotExist(err) { @@ -108,13 +107,27 @@ func WriteFileAtomic(filePath string, newBytes []byte, mode os.FileMode) error { return fmt.Errorf("Could not write file %v. %v", filePath+".bak", err) } } - // Write newBytes to filePath.new - err := ioutil.WriteFile(filePath+".new", newBytes, mode) + f, err := ioutil.TempFile("", "") if err != nil { - return fmt.Errorf("Could not write file %v. %v", filePath+".new", err) + return err + } + _, err = f.Write(newBytes) + if err == nil { + err = f.Sync() + } + if closeErr := f.Close(); err == nil { + err = closeErr + } + if permErr := os.Chmod(f.Name(), mode); err == nil { + err = permErr + } + if err == nil { + err = os.Rename(f.Name(), filePath) + } + // any err should result in full cleanup + if err != nil { + os.Remove(f.Name()) } - // Move filePath.new to filePath - err = os.Rename(filePath+".new", filePath) return err }