Сделал обновление, приехало такое:

eglibc (2.13-3) unstable; urgency=low

Starting with version 2.13, eglibc provides an SSSE3 optimized version of memcpy() on the amd64 architecture. This version might copy memory backward in some conditions, which causes issues if the source and destination overlap. memmove() should be used in such cases, but some programs still wrongly use memcpy().

For this reason, on the amd64 architecture the Debian package provides two wrappers which can be use to workaround and/or debug the issue:
— /usr/lib/libc/memcpy-preload.so simply replace all calls to memcpy()
by a call to memmove()
— /usr/lib/libc/memcpy-syslog-preload.so does the same, but in addition
logs (with rate limit) the issue to syslog, so that it can be
detected and fixed.

To use these wrapper on a single binary, the easiest way is to use the LD_PRELOAD environment variable:
— LD_PRELOAD=/usr/lib/libc/memcpy-preload.so /path/to/binary
— LD_PRELOAD=/usr/lib/libc/memcpy-syslog-preload.so /path/to/binary

For system-wide usage, it is possible to add the path of one of the wrapper to /etc/ld.so.preload.

For more details about the issue, please see:
http://bugs.debian.org/625521
http://sourceware.org/bugzilla/show_bug....

-- Aurelien Jarno <aurel32@debian.org> Wed, 11 May 2011 22:15:31 +0200

Внезапное копирование задом наперёд (я в курсе, что блок не перевернётся, но сама формулировка убила, равно как и костыли для обхода).

#igniz

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