http://lists.freebsd.org/pipermail/freebsd-hackers/2011-January/034254.html

From owner-freebsd-hackers@@@freebsd.org Tue Feb  1 00:10:15 2011
Message-Id: <201101312218.p0VMIs90003417@@@fire.js.berklix.net>
To: hackers@@@freebsd.org, netbsd-users@@@NetBSD.org
From: "Julian H. Stacey" <jhs@@@berklix.com>
Organization: http://www.berklix.com BSD Linux Unix Consultancy, Munich Germany
User-agent: EXMH on FreeBSD http://www.berklix.com/free/
X-URL: http://www.berklix.com/~jhs/cv/
Date: Mon, 31 Jan 2011 23:18:54 +0100
Cc: 
Subject: usr.bin/tar/ ignores error codes from read() just silently pads
	nulls
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Hi hackers@@@freebsd.org & netbsd-users@@@NetBSD.org
usr.bin/tar ignores device error codes from read() & silently pads nulls.  See
  FreeBSD 6.2 6.4 7.3, 8.0, 8.1, & current src/usr.bin/tar/write.c
  NetBSD 5.1 & current src/external/bsd/libarchive/dist/tar/write.c
	^write_file_data(
	last 3 lines ... bytes_read = read

I filed a send-pr yesterday Mon, 31 Jan 2011 04:52:29 +0100 (CET)
	http://www.freebsd.org/cgi/query-pr.cgi?pr=154407
diffs slightly cleaned up here:
	http://berklix.com/~jhs/src/bsd/fixes/FreeBSD/src/gen/usr.bin/tar/
Tar author will probably issue cleaner code as soon as he has time.

Meantime, if you may have copied in data without realising media was flakey,
bsdtar will not have warned (though /var/log/messages does), so
you may want to scan with find & a detector eg
	http://berklix.com/~jhs/src/bsd/jhs/bin/public/8f/

Cheers,
Julian
-- 
Julian Stacey, BSD Unix Linux C Sys Eng Consultants Munich http://berklix.com
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