This mostly reverts commit bc9bbeb2b8
"libarchive: do not extract unsafe symlinks unless $EXTRACT_UNSAFE_SYMLINKS=1"
Users report that it is somewhat too restrictive. See
https://bugs.busybox.net/show_bug.cgi?id=8411
In particular, this interferes with unpacking of busybox-based
filesystems with links like "sbin/applet" -> "../bin/busybox".
The change is made smaller by deleting ARCHIVE_EXTRACT_QUIET flag -
it is unused since 2010, and removing conditionals on it
allows commonalizing some error message codes.
function                                             old     new   delta
create_or_remember_symlink                             -      94     +94
create_symlinks_from_list                              -      64     +64
tar_main                                            1002    1006      +4
unzip_main                                          2732    2724      -8
data_extract_all                                     984     891     -93
unsafe_symlink_target                                147       -    -147
------------------------------------------------------------------------------
(add/remove: 2/1 grow/shrink: 1/2 up/down: 162/-248)          Total: -86 bytes
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
		
	
		
			
				
	
	
		
			369 lines
		
	
	
		
			10 KiB
		
	
	
	
		
			Bash
		
	
	
		
			Executable File
		
	
	
	
	
			
		
		
	
	
			369 lines
		
	
	
		
			10 KiB
		
	
	
	
		
			Bash
		
	
	
		
			Executable File
		
	
	
	
	
#!/bin/sh
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# Copyright 2009 by Denys Vlasenko
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# Licensed under GPLv2, see file LICENSE in this source tree.
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. ./testing.sh
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unset LANG
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unset LANGUAGE
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unset LC_COLLATE
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unset LC_ALL
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umask 022
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# testing "test name" "script" "expected result" "file input" "stdin"
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testing "Empty file is not a tarball" '\
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tar xvf - 2>&1; echo $?
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' "\
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tar: short read
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1
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" \
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"" ""
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SKIP=
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optional FEATURE_SEAMLESS_GZ GUNZIP
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# In NOMMU case, "invalid magic" message comes from gunzip child process.
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# Otherwise, it comes from tar.
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# Need to fix output up to avoid false positive.
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testing "Empty file is not a tarball.tar.gz" '\
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{ tar xvzf - 2>&1; echo $?; } | grep -Fv "invalid magic"
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' "\
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tar: short read
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1
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" \
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"" ""
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SKIP=
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testing "Two zeroed blocks is a ('truncated') empty tarball" '\
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dd if=/dev/zero bs=512 count=2 2>/dev/null | tar xvf - 2>&1; echo $?
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' "\
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0
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" \
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"" ""
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SKIP=
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testing "Twenty zeroed blocks is an empty tarball" '\
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dd if=/dev/zero bs=512 count=20 2>/dev/null | tar xvf - 2>&1; echo $?
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' "\
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0
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" \
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"" ""
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SKIP=
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mkdir tar.tempdir && cd tar.tempdir || exit 1
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# "tar cf test.tar input input_dir/ input_hard1 input_hard2 input_hard1 input_dir/ input":
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# GNU tar 1.26 records as hardlinks:
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#  input_hard2 -> input_hard1
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#  input_hard1 -> input_hard1 (!!!)
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#  input_dir/file -> input_dir/file
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#  input -> input
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# As of 1.24.0, we don't record last two: for them, nlink==1
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# and we check for "hardlink"ness only files with nlink!=1
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# We also don't use "hrw-r--r--" notation for hardlinks in "tar tv" listing.
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optional FEATURE_TAR_CREATE FEATURE_LS_SORTFILES
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testing "tar hardlinks and repeated files" '\
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>input_hard1
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ln input_hard1 input_hard2
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mkdir input_dir
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>input_dir/file
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chmod -R 644 *
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chmod    755 input_dir
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tar cf test.tar input input_dir/ input_hard1 input_hard2 input_hard1 input_dir/ input
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tar tvf test.tar | sed "s/.*[0-9] input/input/"
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rm -rf input_dir
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tar xf test.tar 2>&1
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echo Ok: $?
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ls -l . input_dir/* | grep input_ | sed "s/\\(^[^ ]*\\) .* input/\\1 input/"
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' "\
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input
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input_dir/
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input_dir/file
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input_hard1
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input_hard2 -> input_hard1
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input_hard1 -> input_hard1
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input_dir/
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input_dir/file
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input
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Ok: 0
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-rw-r--r-- input_dir/file
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drwxr-xr-x input_dir
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-rw-r--r-- input_hard1
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-rw-r--r-- input_hard2
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" \
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"" ""
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SKIP=
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cd .. || exit 1; rm -rf tar.tempdir 2>/dev/null
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mkdir tar.tempdir && cd tar.tempdir || exit 1
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optional FEATURE_TAR_CREATE FEATURE_LS_SORTFILES
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testing "tar hardlinks mode" '\
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>input_hard1
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chmod 741 input_hard1
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ln input_hard1 input_hard2
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mkdir input_dir
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ln input_hard1 input_dir
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ln input_hard2 input_dir
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chmod 550 input_dir
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# On some filesystems, input_dir/input_hard2 is returned by readdir
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# BEFORE input_dir/input_hard1! Thats why we cant just "tar cf ... input_*":
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tar cf test.tar input_dir/input_hard* input_hard*
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tar tvf test.tar | sed "s/.*[0-9] input/input/"
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chmod 770 input_dir
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rm -rf input_*
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tar xf test.tar 2>&1
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echo Ok: $?
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ls -l . input_dir/* | grep "input.*hard" | sed "s/\\(^[^ ]*\\) .* input/\\1 input/"
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' "\
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input_dir/input_hard1
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input_dir/input_hard2 -> input_dir/input_hard1
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input_hard1 -> input_dir/input_hard1
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input_hard2 -> input_dir/input_hard1
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Ok: 0
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-rwxr----x input_dir/input_hard1
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-rwxr----x input_dir/input_hard2
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-rwxr----x input_hard1
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-rwxr----x input_hard2
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" \
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"" ""
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SKIP=
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cd .. || exit 1; rm -rf tar.tempdir 2>/dev/null
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mkdir tar.tempdir && cd tar.tempdir || exit 1
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optional FEATURE_TAR_CREATE FEATURE_LS_SORTFILES
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testing "tar symlinks mode" '\
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>input_file
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chmod 741 input_file
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ln -s input_file input_soft
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mkdir input_dir
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ln input_file input_dir
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ln input_soft input_dir
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chmod 550 input_dir
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tar cf test.tar input_dir/* input_[fs]*
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tar tvf test.tar | sed "s/.*[0-9] input/input/" | sort
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chmod 770 input_dir
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rm -rf input_*
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tar xf test.tar 2>&1
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echo Ok: $?
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ls -l . input_dir/* | grep "input_[fs]" | sed "s/\\(^[^ ]*\\) .* input/\\1 input/"
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' "\
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input_dir/input_file
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input_dir/input_soft -> input_file
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input_file -> input_dir/input_file
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input_soft -> input_dir/input_soft
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Ok: 0
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-rwxr----x input_dir/input_file
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lrwxrwxrwx input_file
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-rwxr----x input_file
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lrwxrwxrwx input_file
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" \
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"" ""
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SKIP=
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cd .. || exit 1; rm -rf tar.tempdir 2>/dev/null
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mkdir tar.tempdir && cd tar.tempdir || exit 1
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optional FEATURE_TAR_CREATE FEATURE_TAR_LONG_OPTIONS
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testing "tar --overwrite" "\
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ln input input_hard
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tar cf test.tar input_hard
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echo WRONG >input
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# --overwrite opens 'input_hard' without unlinking,
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# thus 'input_hard' still linked to 'input' and we write 'Ok' into it
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tar xf test.tar --overwrite 2>&1 && cat input
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" "\
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Ok
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" \
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"Ok\n" ""
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SKIP=
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cd .. || exit 1; rm -rf tar.tempdir 2>/dev/null
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mkdir tar.tempdir && cd tar.tempdir || exit 1
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test x"$SKIP_KNOWN_BUGS" = x"" && {
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# Needs to be run under non-root for meaningful test
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optional FEATURE_TAR_CREATE
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testing "tar writing into read-only dir" '\
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mkdir input_dir
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>input_dir/input_file
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chmod 550 input_dir
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tar cf test.tar input_dir
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tar tvf test.tar | sed "s/.*[0-9] input/input/"
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chmod 770 input_dir
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rm -rf input_*
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tar xf test.tar 2>&1
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echo Ok: $?
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ls -l input_dir/* . | grep input_ | sed "s/\\(^[^ ]*\\) .* input/\\1 input/"
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chmod 770 input_dir
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' "\
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input_dir/
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input_dir/input_file
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Ok: 0
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-rw-r--r-- input_dir/input_file
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dr-xr-x--- input_dir
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" \
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"" ""
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SKIP=
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}
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cd .. || exit 1; rm -rf tar.tempdir 2>/dev/null
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mkdir tar.tempdir && cd tar.tempdir || exit 1
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# Had a bug where on extract autodetect first "switched off" -z
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# and then failed to recognize .tgz extension
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optional FEATURE_TAR_CREATE FEATURE_SEAMLESS_GZ GUNZIP
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testing "tar extract tgz" "\
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dd count=1 bs=1M if=/dev/zero of=F0 2>/dev/null
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tar -czf F0.tgz F0
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rm F0
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tar -xzvf F0.tgz && echo Ok
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rm F0 || echo BAD
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" "\
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F0
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Ok
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" \
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"" ""
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SKIP=
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cd .. || exit 1; rm -rf tar.tempdir 2>/dev/null
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mkdir tar.tempdir && cd tar.tempdir || exit 1
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# Do we detect XZ-compressed data (even w/o .tar.xz or txz extension)?
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# (the uuencoded hello_world.txz contains one empty file named "hello_world")
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optional UUDECODE FEATURE_TAR_AUTODETECT FEATURE_SEAMLESS_XZ
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testing "tar extract txz" "\
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uudecode -o input && tar tf input && echo Ok
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" "\
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hello_world
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Ok
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" \
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"" "\
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begin-base64 644 hello_world.txz
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/Td6WFoAAATm1rRGAgAhARYAAAB0L+Wj4AX/AEldADQZSe6ODIZQ3rSQ8kAJ
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SnMPTX+XWGKW3Yu/Rwqg4Ik5wqgQKgVH97J8yA8IvZ4ahaCQogUNHRkXibr2
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Q615wcb2G7fJU49AhWAAAAAAUA8gu9DyXfAAAWWADAAAAB5FXGCxxGf7AgAA
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AAAEWVo=
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====
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"
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SKIP=
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cd .. || exit 1; rm -rf tar.tempdir 2>/dev/null
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mkdir tar.tempdir && cd tar.tempdir || exit 1
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# On extract, everything up to and including last ".." component is stripped
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optional FEATURE_TAR_CREATE
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testing "tar strips /../ on extract" "\
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rm -rf input_* test.tar 2>/dev/null
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mkdir input_dir
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echo Ok >input_dir/file
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tar cf test.tar ./../tar.tempdir/input_dir/../input_dir 2>&1
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rm -rf input_* 2>/dev/null
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tar -vxf test.tar 2>&1
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cat input_dir/file 2>&1
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" "\
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tar: removing leading './../tar.tempdir/input_dir/../' from member names
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input_dir/
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input_dir/file
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Ok
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" \
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"" ""
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SKIP=
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cd .. || exit 1; rm -rf tar.tempdir 2>/dev/null
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mkdir tar.tempdir && cd tar.tempdir || exit 1
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# attack.tar.bz2 has symlink pointing to a system file
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# followed by a regular file with the same name
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# containing "root::0:0::/root:/bin/sh":
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#  lrwxrwxrwx root/root passwd -> /tmp/passwd
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#  -rw-r--r-- root/root passwd
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# naive tar implementation may end up creating the symlink
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# and then writing into it.
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# The correct implementation unlinks target before
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# creating the second file.
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# We test that /tmp/passwd remains empty:
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optional UUDECODE FEATURE_TAR_AUTODETECT FEATURE_SEAMLESS_BZ2
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testing "tar does not extract into symlinks" "\
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>>/tmp/passwd && uudecode -o input && tar xf input 2>&1 && rm passwd; cat /tmp/passwd; echo \$?
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" "\
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tar: can't create symlink 'passwd' to '/tmp/passwd'
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0
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" \
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"" "\
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begin-base64 644 attack.tar.bz2
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QlpoOTFBWSZTWRVn/bIAAKt7hMqwAEBAAP2QAhB0Y96AAACACCAAlISgpqe0
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po0DIaDynqAkpDRP1ANAhiYNSPR8VchKhAz0AK59+DA6FcMKBggOARIJdVHL
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DGllrjs20ATUgR1HmccBX3EhoMnpMJaNyggmxgLDMz54lBnBTJO/1L1lbMS4
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l4/V8LDoe90yiWJhOJvIypgEfxdyRThQkBVn/bI=
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====
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"
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SKIP=
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cd .. || exit 1; rm -rf tar.tempdir 2>/dev/null
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mkdir tar.tempdir && cd tar.tempdir || exit 1
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# And same with -k
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optional UUDECODE FEATURE_TAR_AUTODETECT FEATURE_SEAMLESS_BZ2
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testing "tar -k does not extract into symlinks" "\
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>>/tmp/passwd && uudecode -o input && tar xf input -k 2>&1 && rm passwd; cat /tmp/passwd; echo \$?
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" "\
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tar: can't create symlink 'passwd' to '/tmp/passwd'
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0
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" \
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"" "\
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begin-base64 644 attack.tar.bz2
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QlpoOTFBWSZTWRVn/bIAAKt7hMqwAEBAAP2QAhB0Y96AAACACCAAlISgpqe0
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po0DIaDynqAkpDRP1ANAhiYNSPR8VchKhAz0AK59+DA6FcMKBggOARIJdVHL
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DGllrjs20ATUgR1HmccBX3EhoMnpMJaNyggmxgLDMz54lBnBTJO/1L1lbMS4
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l4/V8LDoe90yiWJhOJvIypgEfxdyRThQkBVn/bI=
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====
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"
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SKIP=
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cd .. || exit 1; rm -rf tar.tempdir 2>/dev/null
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mkdir tar.tempdir && cd tar.tempdir || exit 1
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optional UNICODE_SUPPORT FEATURE_TAR_GNU_EXTENSIONS FEATURE_SEAMLESS_BZ2 FEATURE_TAR_AUTODETECT
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testing "Pax-encoded UTF8 names and symlinks" '\
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tar xvf ../tar.utf8.tar.bz2 2>&1; echo $?
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export LANG=en_US.UTF-8
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ls -l etc/ssl/certs/* | sed "s:.*etc/:etc/:" | sort
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unset LANG
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rm -rf etc usr
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' "\
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etc/ssl/certs/3b2716e5.0
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etc/ssl/certs/EBG_Elektronik_Sertifika_Hizmet_Sağlayıcısı.pem
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etc/ssl/certs/f80cc7f6.0
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usr/share/ca-certificates/mozilla/EBG_Elektronik_Sertifika_Hizmet_Sağlayıcısı.crt
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0
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etc/ssl/certs/3b2716e5.0 -> EBG_Elektronik_Sertifika_Hizmet_Sağlayıcısı.pem
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etc/ssl/certs/EBG_Elektronik_Sertifika_Hizmet_Sağlayıcısı.pem -> /usr/share/ca-certificates/mozilla/EBG_Elektronik_Sertifika_Hizmet_Sağlayıcısı.crt
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etc/ssl/certs/f80cc7f6.0 -> EBG_Elektronik_Sertifika_Hizmet_Sağlayıcısı.pem
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" \
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"" ""
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SKIP=
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cd .. || exit 1; rm -rf tar.tempdir 2>/dev/null
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mkdir tar.tempdir && cd tar.tempdir || exit 1
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optional FEATURE_SEAMLESS_BZ2 FEATURE_TAR_AUTODETECT
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testing "Symlink attack: create symlink and then write through it" '\
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exec 2>&1
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uudecode -o input && tar xvf input; echo $?
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ls /tmp/bb_test_evilfile
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ls bb_test_evilfile
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ls symlink/bb_test_evilfile
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' "\
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anything.txt
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symlink
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symlink/bb_test_evilfile
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tar: can't create symlink 'symlink' to '/tmp'
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1
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ls: /tmp/bb_test_evilfile: No such file or directory
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ls: bb_test_evilfile: No such file or directory
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symlink/bb_test_evilfile
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" \
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"" "\
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begin-base64 644 tar_symlink_attack.tar.bz2
 | 
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QlpoOTFBWSZTWZgs7bQAALT/hMmQAFBAAf+AEMAGJPPv32AAAIAIMAC5thlR
 | 
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omAjAmCMADQT1BqNE0AEwAAjAEwElTKeo9NTR6h6gaeoA0DQNLVdwZZ5iNTk
 | 
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AQwCAV6S00QFJYhrlfFkVCEDEGtgNVqYrI0uK3ggnt30gqk4e1TTQm5QIAKa
 | 
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SJqzRGSFLMmOloHSAcvLiFxxRiQtQZF+qPxbo173ZDISOAoNoPN4PQPhBhKS
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n8fYaKlioCTzL2oXYczyUUIP4u5IpwoSEwWdtoA=
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====
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"
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SKIP=
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cd .. || exit 1; rm -rf tar.tempdir 2>/dev/null
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exit $FAILCOUNT
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