fix(handlers): fix edge cases in tar handler (empty name, too long name).

tarfile python library does not perform any kind of defensive
programming and will trigger OS level errors like ENAMETOOLONG trying to
write files that have long names.

This commit adds two checks to our safe implementation of tarfile so
that we log the issue with a warning and skip the file.

Note: tar files with such entries (long name, empty name) do not happen
naturally and must be synthesized. That's why decided to skip them, in a
similar fashion than GNU tar and 7zip.

Author: qkaiser

tests/integration/archive/tar/__input__/emptyname.tar

@@ -0,0 +1,3 @@
+version https://git-lfs.github.com/spec/v1
+oid sha256:8b5233dfb3a4a23a3bf291bfff8ccfb371fbb2136cb093247d30af090d1e4276
+size 10240

tests/integration/archive/tar/__input__/longname.tar

@@ -0,0 +1,3 @@
+version https://git-lfs.github.com/spec/v1
+oid sha256:bd002ebcec73917b4294602e2999809e4119f5209a74f92fc0f70bff838bca69
+size 10240

tests/integration/archive/tar/__output__/emptyname.tar_extract/apple.txt

@@ -0,0 +1,3 @@
+version https://git-lfs.github.com/spec/v1
+oid sha256:303980bcb9e9e6cdec515230791af8b0ab1aaa244b58a8d99152673aa22197d0
+size 6

tests/integration/archive/tar/__output__/longname.tar_extract/apple.txt

@@ -0,0 +1,3 @@
+version https://git-lfs.github.com/spec/v1
+oid sha256:303980bcb9e9e6cdec515230791af8b0ab1aaa244b58a8d99152673aa22197d0
+size 6

unblob/handlers/archive/_safe_tarfile.py

@@ -9,6 +9,7 @@
 logger = get_logger()
 
 RUNNING_AS_ROOT = os.getuid() == 0
+MAX_PATH_LEN = 255
 
 
 class SafeTarFile(TarFile):
@@ -18,6 +19,14 @@ def extract(
         path_as_path = Path(str(path))
         member_name_path = Path(str(member.name))
 
+        if not member.name:
+            logger.warning("File with empty filename in tar archive. Skipping")
+            return
+
+        if len(member.name) > MAX_PATH_LEN:
+            logger.warning("File with filename too long in tar archive. Skipping")
+            return
+
         if not RUNNING_AS_ROOT and (member.ischr() or member.isblk()):
             logger.warning(
                 "missing elevated permissions, skipping block and character device creation",