Moderate: gdb (SL6)

Synopsis: Moderate: gdb security and bug fix update
Issue Date: 2013-02-21
CVE Numbers: CVE-2011-4355

GDB tried to auto-load certain files (such as GDB scripts, Python scripts, and
a thread debugging library) from the current working directory when debugging
programs. This could result in the execution of arbitrary code with the user’s
privileges when GDB was run in a directory that has untrusted content.

With this update, GDB no longer auto-loads files from the current directory and
only trusts certain system directories by default. The list of trusted
directories can be viewed and modified using the “show auto-load safe-path” and
“set auto-load safe-path” GDB commands.

This update also fixes the following bugs:

* When a struct member was at an offset greater than 256 MB, the resulting bit
position within the struct overflowed and caused an invalid memory access by
GDB. With this update, the code has been modified to ensure that GDB can access
such positions.

* When a thread list of the core file became corrupted, GDB did not print this
list but displayed the “Cannot find new threads: generic error” error message
instead. With this update, GDB has been modified and it now prints the thread
list of the core file as expected.

* GDB did not properly handle debugging of multiple binaries with the same
build ID. This update modifies GDB to use symbolic links created for particular
binaries so that debugging of binaries that share a build ID now proceeds as
expected. Debugging of live programs and core files is now more user-friendly.


– Scientific Linux Development Team