F51 number-size-plusA size with a plus sign, +0000001000.
Reject(draft) A strict parser must reject this archive.
F51-number-size-plus.tar |
test archive, 2,048 bytes
sha256 fa3adbfe14303c138e197bc72709c24b429716a7dd6511d51ff8b9ba9ac82ead |
F51-number-size-plus.json | expected result |
F51-number-size-plus.txt | annotated blocks |
F51-number-size-plus.py | generator script |
The archive has a file a, whose size field is +0000001000, then an empty file smuggled.
In POSIX, numeric fields are octal numbers filled with leading zeros, without a sign. Read leniently, this case is ambiguous because a reader can read the size in one of three ways. A reader that skips the sign reads 512, which is octal 1000, and the next block is the data of a. One that ends the number at the sign reads 0, and the next block is the header of smuggled. One that takes a sign for the start of a base-64 number, as some early test versions of GNU tar wrote them, reads a size far past the end of the archive, and the rest of the archive is the data of a.
Decision point: whether a numeric field may have a sign.
Seen in: none of the scanned tarballs.
Every block of 512 bytes, to scale, with its offset. Hover over a field for its bytes.
F51-number-size-plus: must reject
A size with a plus sign, `+0000001000`.
The archive has a file `a`, whose size field is `+0000001000`, then an empty file `smuggled`.
In POSIX, numeric fields are octal numbers filled with leading zeros, without a sign.
Read leniently, this case is ambiguous because a reader can read the size in one of three ways. A
reader that skips the sign reads 512, which is octal 1000, and the next block is the data of `a`.
One that ends the number at the sign reads 0, and the next block is the header of `smuggled`. One
that takes a sign for the start of a base-64 number, as some early test versions of GNU tar wrote
them, reads a size far past the end of the archive, and the rest of the archive is the data of `a`.
Decision point: whether a numeric field may have a sign.
Seen in: none of the scanned tarballs.
See also: F23, a pax size with a plus sign, and F37, a size with the digit 9.
0x000000 header: regular file, size 512, or 0
name [ 0,100) "a" + 99 NUL
mode [100,108) "0000644" + NUL 644 (octal)
uid [108,116) "0000000" + NUL 0
gid [116,124) "0000000" + NUL 0
size [124,136) "+0000001000" + NUL
mtime [136,148) "00000000000" + NUL 0
chksum [148,156) "007332\0 " 3802: the unsigned sum of the header, this field as spaces
typeflag [156,157) "0" regular file
linkname [157,257) 100 NUL
magic [257,263) "ustar" + NUL
version [263,265) "00"
uname [265,297) 32 NUL
gname [297,329) 32 NUL
devmajor [329,337) "0000000" + NUL 0
devminor [337,345) "0000000" + NUL 0
prefix [345,500) 155 NUL
pad [500,512) 12 NUL
0x000200 header: regular file, the data of a, to an implementation that skips the sign
name [ 0,100) "smuggled" + 92 NUL
mode [100,108) "0000644" + NUL 644 (octal)
uid [108,116) "0000000" + NUL 0
gid [116,124) "0000000" + NUL 0
size [124,136) "00000000000" + NUL 0
mtime [136,148) "00000000000" + NUL 0
chksum [148,156) "010725\0 " 4565: the unsigned sum of the header, this field as spaces
typeflag [156,157) "0" regular file
linkname [157,257) 100 NUL
magic [257,263) "ustar" + NUL
version [263,265) "00"
uname [265,297) 32 NUL
gname [297,329) 32 NUL
devmajor [329,337) "0000000" + NUL 0
devminor [337,345) "0000000" + NUL 0
prefix [345,500) 155 NUL
pad [500,512) 12 NUL
0x000400 2 zero blocks: the end-of-archive marker
0x000800 end of file
As xxd writes it: xxd -r makes the archive of it.
00000000: 6100 0000 0000 0000 0000 0000 0000 0000 a............... 00000010: 0000 0000 0000 0000 0000 0000 0000 0000 ................ 00000020: 0000 0000 0000 0000 0000 0000 0000 0000 ................ 00000030: 0000 0000 0000 0000 0000 0000 0000 0000 ................ 00000040: 0000 0000 0000 0000 0000 0000 0000 0000 ................ 00000050: 0000 0000 0000 0000 0000 0000 0000 0000 ................ 00000060: 0000 0000 3030 3030 3634 3400 3030 3030 ....0000644.0000 00000070: 3030 3000 3030 3030 3030 3000 2b30 3030 000.0000000.+000 00000080: 3030 3031 3030 3000 3030 3030 3030 3030 0001000.00000000 00000090: 3030 3000 3030 3733 3332 0020 3000 0000 000.007332. 0... 000000a0: 0000 0000 0000 0000 0000 0000 0000 0000 ................ 000000b0: 0000 0000 0000 0000 0000 0000 0000 0000 ................ 000000c0: 0000 0000 0000 0000 0000 0000 0000 0000 ................ 000000d0: 0000 0000 0000 0000 0000 0000 0000 0000 ................ 000000e0: 0000 0000 0000 0000 0000 0000 0000 0000 ................ 000000f0: 0000 0000 0000 0000 0000 0000 0000 0000 ................ 00000100: 0075 7374 6172 0030 3000 0000 0000 0000 .ustar.00....... 00000110: 0000 0000 0000 0000 0000 0000 0000 0000 ................ 00000120: 0000 0000 0000 0000 0000 0000 0000 0000 ................ 00000130: 0000 0000 0000 0000 0000 0000 0000 0000 ................ 00000140: 0000 0000 0000 0000 0030 3030 3030 3030 .........0000000 00000150: 0030 3030 3030 3030 0000 0000 0000 0000 .0000000........ 00000160: 0000 0000 0000 0000 0000 0000 0000 0000 ................ 00000170: 0000 0000 0000 0000 0000 0000 0000 0000 ................ 00000180: 0000 0000 0000 0000 0000 0000 0000 0000 ................ 00000190: 0000 0000 0000 0000 0000 0000 0000 0000 ................ 000001a0: 0000 0000 0000 0000 0000 0000 0000 0000 ................ 000001b0: 0000 0000 0000 0000 0000 0000 0000 0000 ................ 000001c0: 0000 0000 0000 0000 0000 0000 0000 0000 ................ 000001d0: 0000 0000 0000 0000 0000 0000 0000 0000 ................ 000001e0: 0000 0000 0000 0000 0000 0000 0000 0000 ................ 000001f0: 0000 0000 0000 0000 0000 0000 0000 0000 ................ 00000200: 736d 7567 676c 6564 0000 0000 0000 0000 smuggled........ 00000210: 0000 0000 0000 0000 0000 0000 0000 0000 ................ 00000220: 0000 0000 0000 0000 0000 0000 0000 0000 ................ 00000230: 0000 0000 0000 0000 0000 0000 0000 0000 ................ 00000240: 0000 0000 0000 0000 0000 0000 0000 0000 ................ 00000250: 0000 0000 0000 0000 0000 0000 0000 0000 ................ 00000260: 0000 0000 3030 3030 3634 3400 3030 3030 ....0000644.0000 00000270: 3030 3000 3030 3030 3030 3000 3030 3030 000.0000000.0000 00000280: 3030 3030 3030 3000 3030 3030 3030 3030 0000000.00000000 00000290: 3030 3000 3031 3037 3235 0020 3000 0000 000.010725. 0... 000002a0: 0000 0000 0000 0000 0000 0000 0000 0000 ................ 000002b0: 0000 0000 0000 0000 0000 0000 0000 0000 ................ 000002c0: 0000 0000 0000 0000 0000 0000 0000 0000 ................ 000002d0: 0000 0000 0000 0000 0000 0000 0000 0000 ................ 000002e0: 0000 0000 0000 0000 0000 0000 0000 0000 ................ 000002f0: 0000 0000 0000 0000 0000 0000 0000 0000 ................ 00000300: 0075 7374 6172 0030 3000 0000 0000 0000 .ustar.00....... 00000310: 0000 0000 0000 0000 0000 0000 0000 0000 ................ 00000320: 0000 0000 0000 0000 0000 0000 0000 0000 ................ 00000330: 0000 0000 0000 0000 0000 0000 0000 0000 ................ 00000340: 0000 0000 0000 0000 0030 3030 3030 3030 .........0000000 00000350: 0030 3030 3030 3030 0000 0000 0000 0000 .0000000........ 00000360: 0000 0000 0000 0000 0000 0000 0000 0000 ................ 00000370: 0000 0000 0000 0000 0000 0000 0000 0000 ................ 00000380: 0000 0000 0000 0000 0000 0000 0000 0000 ................ 00000390: 0000 0000 0000 0000 0000 0000 0000 0000 ................ 000003a0: 0000 0000 0000 0000 0000 0000 0000 0000 ................ 000003b0: 0000 0000 0000 0000 0000 0000 0000 0000 ................ 000003c0: 0000 0000 0000 0000 0000 0000 0000 0000 ................ 000003d0: 0000 0000 0000 0000 0000 0000 0000 0000 ................ 000003e0: 0000 0000 0000 0000 0000 0000 0000 0000 ................ 000003f0: 0000 0000 0000 0000 0000 0000 0000 0000 ................ 00000400: 0000 0000 0000 0000 0000 0000 0000 0000 ................ 00000410: 0000 0000 0000 0000 0000 0000 0000 0000 ................ 00000420: 0000 0000 0000 0000 0000 0000 0000 0000 ................ 00000430: 0000 0000 0000 0000 0000 0000 0000 0000 ................ 00000440: 0000 0000 0000 0000 0000 0000 0000 0000 ................ 00000450: 0000 0000 0000 0000 0000 0000 0000 0000 ................ 00000460: 0000 0000 0000 0000 0000 0000 0000 0000 ................ 00000470: 0000 0000 0000 0000 0000 0000 0000 0000 ................ 00000480: 0000 0000 0000 0000 0000 0000 0000 0000 ................ 00000490: 0000 0000 0000 0000 0000 0000 0000 0000 ................ 000004a0: 0000 0000 0000 0000 0000 0000 0000 0000 ................ 000004b0: 0000 0000 0000 0000 0000 0000 0000 0000 ................ 000004c0: 0000 0000 0000 0000 0000 0000 0000 0000 ................ 000004d0: 0000 0000 0000 0000 0000 0000 0000 0000 ................ 000004e0: 0000 0000 0000 0000 0000 0000 0000 0000 ................ 000004f0: 0000 0000 0000 0000 0000 0000 0000 0000 ................ 00000500: 0000 0000 0000 0000 0000 0000 0000 0000 ................ 00000510: 0000 0000 0000 0000 0000 0000 0000 0000 ................ 00000520: 0000 0000 0000 0000 0000 0000 0000 0000 ................ 00000530: 0000 0000 0000 0000 0000 0000 0000 0000 ................ 00000540: 0000 0000 0000 0000 0000 0000 0000 0000 ................ 00000550: 0000 0000 0000 0000 0000 0000 0000 0000 ................ 00000560: 0000 0000 0000 0000 0000 0000 0000 0000 ................ 00000570: 0000 0000 0000 0000 0000 0000 0000 0000 ................ 00000580: 0000 0000 0000 0000 0000 0000 0000 0000 ................ 00000590: 0000 0000 0000 0000 0000 0000 0000 0000 ................ 000005a0: 0000 0000 0000 0000 0000 0000 0000 0000 ................ 000005b0: 0000 0000 0000 0000 0000 0000 0000 0000 ................ 000005c0: 0000 0000 0000 0000 0000 0000 0000 0000 ................ 000005d0: 0000 0000 0000 0000 0000 0000 0000 0000 ................ 000005e0: 0000 0000 0000 0000 0000 0000 0000 0000 ................ 000005f0: 0000 0000 0000 0000 0000 0000 0000 0000 ................ 00000600: 0000 0000 0000 0000 0000 0000 0000 0000 ................ 00000610: 0000 0000 0000 0000 0000 0000 0000 0000 ................ 00000620: 0000 0000 0000 0000 0000 0000 0000 0000 ................ 00000630: 0000 0000 0000 0000 0000 0000 0000 0000 ................ 00000640: 0000 0000 0000 0000 0000 0000 0000 0000 ................ 00000650: 0000 0000 0000 0000 0000 0000 0000 0000 ................ 00000660: 0000 0000 0000 0000 0000 0000 0000 0000 ................ 00000670: 0000 0000 0000 0000 0000 0000 0000 0000 ................ 00000680: 0000 0000 0000 0000 0000 0000 0000 0000 ................ 00000690: 0000 0000 0000 0000 0000 0000 0000 0000 ................ 000006a0: 0000 0000 0000 0000 0000 0000 0000 0000 ................ 000006b0: 0000 0000 0000 0000 0000 0000 0000 0000 ................ 000006c0: 0000 0000 0000 0000 0000 0000 0000 0000 ................ 000006d0: 0000 0000 0000 0000 0000 0000 0000 0000 ................ 000006e0: 0000 0000 0000 0000 0000 0000 0000 0000 ................ 000006f0: 0000 0000 0000 0000 0000 0000 0000 0000 ................ 00000700: 0000 0000 0000 0000 0000 0000 0000 0000 ................ 00000710: 0000 0000 0000 0000 0000 0000 0000 0000 ................ 00000720: 0000 0000 0000 0000 0000 0000 0000 0000 ................ 00000730: 0000 0000 0000 0000 0000 0000 0000 0000 ................ 00000740: 0000 0000 0000 0000 0000 0000 0000 0000 ................ 00000750: 0000 0000 0000 0000 0000 0000 0000 0000 ................ 00000760: 0000 0000 0000 0000 0000 0000 0000 0000 ................ 00000770: 0000 0000 0000 0000 0000 0000 0000 0000 ................ 00000780: 0000 0000 0000 0000 0000 0000 0000 0000 ................ 00000790: 0000 0000 0000 0000 0000 0000 0000 0000 ................ 000007a0: 0000 0000 0000 0000 0000 0000 0000 0000 ................ 000007b0: 0000 0000 0000 0000 0000 0000 0000 0000 ................ 000007c0: 0000 0000 0000 0000 0000 0000 0000 0000 ................ 000007d0: 0000 0000 0000 0000 0000 0000 0000 0000 ................ 000007e0: 0000 0000 0000 0000 0000 0000 0000 0000 ................ 000007f0: 0000 0000 0000 0000 0000 0000 0000 0000 ................
In the outcome column, ✅ means that the implementation follows the default policy.
| implementation | version | outcome | what it makes of it |
|---|---|---|---|
| GNU tar | tar (GNU tar) 1.35 | ✅ rejects | error: tar: Archive contains obsolescent base-64 headers tar: Unexpected EOF in archive tar: Unexpected EOF in archive tar: Error is not recoverable: exiting now |
| bsdtar | bsdtar 3.8.11 - libarchive 3.8.11 | ✅ rejects | error: bsdtar: Error opening archive: Unrecognized archive format |
| BusyBox tar | BusyBox v1.38.0, defconfig | ⚠️ accepts | tree A: a (512 B, 917dba8e) |
| 7-Zip | 7-Zip (z) 26.05 (x64) | ✅ rejects | error: ERROR: suite/archives/F51-number-size-plus.tar suite/archives/F51-number-size-plus.tar Open ERROR: Cannot open the file as [tar] archive ERRORS: Is not archive |
| Python tarfile, filter=data, as in pip | CPython 3.15.2 | ⚠️ accepts | tree A: a (512 B, 917dba8e) |
| Python tarfile, filter=tar | CPython 3.15.2 | ⚠️ accepts | tree A: a (512 B, 917dba8e) |
| Python tarfile, filter=fully_trusted | CPython 3.15.2 | ⚠️ accepts | tree A: a (512 B, 917dba8e) |
| node-tar | tar 7.5.22 | ⚠️ accepts | tree A: a (512 B, 917dba8e) |
| node-tar, strict | tar 7.5.22 | ⚠️ accepts | tree A: a (512 B, 917dba8e) |
| tar-fs | tar-fs 3.1.3, on tar-stream 3.2.2 | ⚠️ accepts | tree A: a (512 B, 917dba8e) |
| Java Commons Compress | Commons Compress 1.28.0, Expander, on Java 27.0.1.0.2 | ✅ rejects | error: java.io.IOException: Corrupted TAR archive. |
| .NET System.Formats.Tar | System.Formats.Tar of .NET 10.0.14, ExtractToDirectory | ✅ rejects | error: InvalidDataException: Unable to parse number. |
| PHP PharData, as in Composer | PharData of PHP 8.5.12, as Composer's TarDownloader calls it | ✅ rejects | error: UnexpectedValueException: phar error: "suite/archives/F51-number-size-plus.tar" is a corrupted tar file (invalid entry size) |
| Go containerd archive.Apply | containerd v2.4.2, archive.Apply, of go1.27.3 | ✅ rejects | error: archive/tar: invalid tar header |
| Rust tar | tar 0.4.46, unpack | ⚠️ accepts | tree A: a (512 B, 917dba8e) |
| Rust astral-tokio-tar | astral-tokio-tar 0.7.1, unpack | ⚠️ accepts | tree A: a (512 B, 917dba8e) |
| Rust tar-codec, as in uv | tar-codec 0.0.16, with the policies of uv 0.13 | ✅ rejects | error: at byte 0: invalid tar size field: found [43, 48, 48, 48, 48, 48, 48, 49, 48, 48, 48, 0] |
| RubyGems | RubyGems 4.0.20 of Ruby 4.0.9, extract_tar_gz | ✅ rejects | error: Gem::Package::TarInvalidError: "+0000001000" is not an octal string |
| R untar, internal | utils::untar of R 4.6.2, tar = "internal" | ✅ rejects | error: invalid octal digit |
| Perl Archive::Tar | Archive::Tar 3.12 of Perl v5.44.0 | ⚠️ accepts | tree B: a (0 B, e3b0c442), smuggled (0 B, e3b0c442) |
| Haskell tar | tar 0.7.2.0, extract, of GHC 9.14 | ✅ rejects | error: HeaderBadNumericEncoding |
| Julia Tar.jl | Tar 1.10.0 of Julia 1.13.3 | ✅ rejects | error: malformed size field: "+0000001000" [header block data]: name = "a\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\… |
| live-bootstrap untar | mescc-tools-extra a151c245e512, as live-bootstrap pins it | ⚠️ accepts | tree A: a (512 B, 917dba8e) |
| live-bootstrap untar, --non-strict | mescc-tools-extra a151c245e512, as live-bootstrap pins it | ⚠️ accepts | tree A: a (512 B, 917dba8e) |
The table below shows how many release tarballs have the features of this test case.
| ecosystem | tarballs | with it | share |
|---|---|---|---|
| Spack | 37,553 | 0 | none |
| nixpkgs | 18,990 | 0 | none |
| Guix | 10,168 | 0 | none |
| PyPI | 10,000 | 0 | none |
| crates.io | 5,000 | 0 | none |
| RubyGems | 5,000 | 0 | none |
| live-bootstrap | 171 | 0 | none |
| total (distinct) | 82,586 | 0 | none |