diff --git a/frameworks/native/backup_ext/include/tar_file.h b/frameworks/native/backup_ext/include/tar_file.h
index 1310a35fa2c63803b9408685b7026d350ed13270..f948312c2e4db7da3a645c4e5aef39d614c1e5ee 100644
--- a/frameworks/native/backup_ext/include/tar_file.h
+++ b/frameworks/native/backup_ext/include/tar_file.h
@@ -132,9 +132,8 @@ private:
      *
      * @param ioBuffer 写入的文件信息
      * @param read 读取文件
-     * @param isFilled 是否写完
      */
-    off_t SplitWriteAll(const std::vector<uint8_t> &ioBuffer, off_t read, bool &isFilled);
+    off_t SplitWriteAll(const std::vector<uint8_t> &ioBuffer, off_t read);
 
     /**
      * @brief creaat split tarfile
diff --git a/frameworks/native/backup_ext/src/ext_extension.cpp b/frameworks/native/backup_ext/src/ext_extension.cpp
index 8f81a35c1f71c9f0043929bffabb7f939bf14066..b411c4701772aa5dae0e014df197f7090eb44b4a 100644
--- a/frameworks/native/backup_ext/src/ext_extension.cpp
+++ b/frameworks/native/backup_ext/src/ext_extension.cpp
@@ -1173,7 +1173,7 @@ static CompareFilesResult CompareFiles(const UniqueFd &cloudFd, const UniqueFd &
         }
 
         allFiles.try_emplace(path, item.second);
-        if (!isExist || (item.second.isDir == false && item.second.isIncremental == true &&
+        if (item.second.isDir == false && item.second.isIncremental == true && (!isExist ||
              cloudFiles.find(path)->second.hash != item.second.hash)) {
             // 在云空间简报里不存在或者hash不一致
             if (item.second.size < BConstants::BIG_FILE_BOUNDARY) {
diff --git a/frameworks/native/backup_ext/src/tar_file.cpp b/frameworks/native/backup_ext/src/tar_file.cpp
index c16510809d25a85d7a07b5da7e6befcab2bf937d..1a68cd62d46db4a760db419e8486c1a6459b4fbd 100644
--- a/frameworks/native/backup_ext/src/tar_file.cpp
+++ b/frameworks/native/backup_ext/src/tar_file.cpp
@@ -223,21 +223,17 @@ bool TarFile::WriteFileContent(const string &fileName, off_t size)
 
     while (remain > 0) {
         off_t read = ioBuffer_.size();
-        if (size < static_cast<off_t>(ioBuffer_.size())) {
-            read = size;
-        } else {
-            if (read > remain) {
-                read = remain;
-            }
+        if (remain < read) {
+            read = remain;
         }
         // read buffer from src file
-        if (ReadAll(fd, ioBuffer_, size) != read) {
+        if (ReadAll(fd, ioBuffer_, read) != read) {
             HILOGE("Failed to read all");
             break;
         }
 
         // write buffer to tar file
-        if (SplitWriteAll(ioBuffer_, read, isFilled) != read) {
+        if (SplitWriteAll(ioBuffer_, read) != read) {
             HILOGE("Failed to split write all");
             break;
         }
@@ -255,7 +251,7 @@ bool TarFile::WriteFileContent(const string &fileName, off_t size)
     return false;
 }
 
-off_t TarFile::SplitWriteAll(const vector<uint8_t> &ioBuffer, off_t read, bool &isFilled)
+off_t TarFile::SplitWriteAll(const vector<uint8_t> &ioBuffer, off_t read)
 {
     off_t len = ioBuffer.size();
     if (len > read) {
@@ -265,8 +261,12 @@ off_t TarFile::SplitWriteAll(const vector<uint8_t> &ioBuffer, off_t read, bool &
     while (count < len) {
         auto writeBytes = fwrite(&ioBuffer[count], sizeof(uint8_t), len - count, currentTarFile_);
         if (writeBytes < 1) {
-            HILOGE("Failed to fwrite tar file, err = %{public}d", errno);
-            return writeBytes;
+            // 再执行一遍
+            auto writeBytes = fwrite(&ioBuffer[count], sizeof(uint8_t), len - count, currentTarFile_);
+            if (writeBytes < 1) {
+                HILOGE("Failed to fwrite tar file, err = %{public}d", errno);
+                return writeBytes;
+            }
         }
         count += writeBytes;
         currentTarFileSize_ += writeBytes;
@@ -365,12 +365,12 @@ void TarFile::FillOwnerName(TarHeader &hdr, const struct stat &st)
     struct passwd *pw = getpwuid(st.st_uid);
     if (pw != nullptr) {
         auto ret = snprintf_s(hdr.uname, sizeof(hdr.uname), sizeof(hdr.uname) - 1, "%s", pw->pw_name);
-        if (ret < 0 || ret >= static_cast<int>(sizeof(hdr.uname))) {
+        if (ret < 0) {
             HILOGE("Fill pw_name failed, err = %{public}d", errno);
         }
     } else {
         auto ret = snprintf_s(hdr.uname, sizeof(hdr.uname), sizeof(hdr.uname) - 1, "%d", st.st_uid);
-        if (ret < 0 || ret >= static_cast<int>(sizeof(hdr.uname))) {
+        if (ret < 0) {
             HILOGE("Fill uid failed, err = %{public}d", errno);
         }
     }
@@ -378,12 +378,12 @@ void TarFile::FillOwnerName(TarHeader &hdr, const struct stat &st)
     struct group *gr = getgrgid(st.st_gid);
     if (gr != nullptr) {
         auto ret = snprintf_s(hdr.gname, sizeof(hdr.gname), sizeof(hdr.gname) - 1, "%s", gr->gr_name);
-        if (ret < 0 || static_cast<int>(sizeof(hdr.gname))) {
+        if (ret < 0) {
             HILOGE("Fill gr_name failed, err = %{public}d", errno);
         }
     } else {
         auto ret = snprintf_s(hdr.gname, sizeof(hdr.gname), sizeof(hdr.gname) - 1, "%d", st.st_gid);
-        if (ret < 0 || ret >= static_cast<int>(sizeof(hdr.gname))) {
+        if (ret < 0) {
             HILOGE("Fill gid failed, err = %{public}d", errno);
         }
     }
@@ -418,9 +418,11 @@ int TarFile::WriteAll(const vector<uint8_t> &buf, size_t len)
 {
     size_t count = 0;
     while (count < len) {
-        auto i = fwrite(&buf[0] + count, sizeof(char), len - count, currentTarFile_);
-        count += i;
-        currentTarFileSize_ += i;
+        auto i = fwrite(&buf[0] + count, sizeof(uint8_t), len - count, currentTarFile_);
+        if (i > 0) {
+            count += i;
+            currentTarFileSize_ += i;
+        }
     }
     return count;
 }