Bug 11531

Summary:	tar: archive with first member named BZh[1-9] is not handled correctly
Product:	Busybox	Reporter:	Michał Górny <mgorny>
Component:	Other	Assignee:	unassigned
Status:	RESOLVED FIXED
Severity:	normal	CC:	busybox-cvs
Priority:	P5
Version:	1.33.x
Target Milestone:	---
Hardware:	All
OS:	Linux
Host:		Target:
Build:

Description Michał Górny 2018-11-26 18:00:36 UTC

If the first .tar member is named BZh[1-9], the archive is incorrectly recognized as bzip2-compressed:

$ busybox tar -xf ustar.tar 
tar: bunzip error -2
tar: short read

While such a filename is not very likely, it's a technically valid tarball.

To reproduce:
$ echo test > BZh5
$ tar -cf ustar.tar BZh5

Comment 1 Denys Vlasenko 2018-11-27 10:27:42 UTC

Fixed in git:

commit f4fc303e3679e4ab0d45f60c31f9b687f27f7452 (HEAD -> master)
Date:   Tue Nov 27 11:26:48 2018 +0100

    tar: fix too eager autodetection