Today, here in the UK, the date is 11/12/13. Today, here in Edinburgh, I we became married.

I've already promised I will make no more than two jokes, ever, about "owning a wife". I will save them for suitable occasions.

For the fifth year in a row the fearless WebKitGTK+ hackers have gathered in A Coru a to bring GNOME and the web closer. Igalia has organized and hosted it as usual, welcoming a record 30 people to its office. The GNOME foundation has sponsored my trip allowing me to fly the cool 18 seats propeller airplane from Lisbon to A Coru a, which is a nice adventure, and have pulpo a feira for dinner, which I simply love! That in addition to enjoying the company of so many great hackers. The goals for the hackfest have been ambitious, as usual, but we made good headway on them. Web the browser (AKA Epiphany) has seen a ton of little improvements, with Carlos splitting the shell search provider to a separate binary, which allowed us to remove some hacks from the session management code from the browser. It also makes testing changes to Web more convenient again. Jon McCan has been pounding at Web s UI making it more sleek, with tabs that expand to make better use of available horizontal space in the tab bar, new dialogs for preferences, cookies and password handling. I have made my tiny contribution by making it not keep tabs that were created just for what turned out to be a download around. For this last day of hackfest I plan to also fix an issue with text encoding detection and help track down a hang that happens upon page load. Martin Robinson and myself have as usual dived into the more disgusting and wide-reaching maintainership tasks that we have lots of trouble pushing forward on our day-to-day lives. Porting our build system to CMake has been one of these long-term goals, not because we love CMake (we don t) or because we hate autotools (we do), but because it should make people s lives easier when adding new files to the build, and should also make our build less hacky and quicker it is sad to see how slow our build can be when compared to something like Chromium, and we think a big part of the problem lies on how complex and dumb autotools and make can be. We have picked up a few of our old branches, brought them up-to-date and landed, which now lets us build the main WebKit2GTK+ library through cmake in trunk. This is an important first step, but there s plenty to do. Under the hood, Dan Winship has been pushing HTTP2 support for libsoup forward, with a dead-tree version of the spec by his side. He is refactoring libsoup internals to accomodate the new code paths. Still on the HTTP front, I have been updating soup s MIME type sniffing support to match the newest living specification, which includes specification for several new types and a new security feature introduced by Internet Explorer and later adopted by other browsers. The huge task of preparing the ground for a one process per tab (or other kinds of process separation, this will still be topic for discussion for a while) has been pushed forward by several hackers, with Carlos Garcia and Andy Wingo leading the charge. Other than that I have been putting in some more work on improving the integration of the new Web Inspector with WebKitGTK+. Carlos has reviewed the patch to allow attaching the inspector to the right side of the window, but we have decided to split it in two, one providing the functionality and one the API that will allow browsers to customize how that is done. There s a lot of work to be done here, I plan to land at least this first patch durign the hackfest. I have also fought one more battle in the never-ending User-Agent sniffing war, in which we cannot win, it looks like. I am very happy to be here for the fifth year in a row, and I hope we will be meeting here for many more years to come! Thanks a lot to Igalia for sponsoring and hosting the hackfest, and to the GNOME foundation for making it possible for me to attend! See you in 2014!

Just a trivial fact: every polyhedron that is used in linear programming is convex, that is !!mathjaxbegin-i!! QXggXGxlcSBi !!mathjaxend-i!! is convex, for a matrix !!mathjaxbegin-i!! QQ== !!mathjaxend-i!! and a (column) vector !!mathjaxbegin-i!! Yg== !!mathjaxend-i!!. Proof: Take any !!mathjaxbegin-i!! eCcsIHgnJw== !!mathjaxend-i!! that satisfy the system of inequalities !!mathjaxbegin-i!! QXggXGxlcSBi !!mathjaxend-i!!. Then, for !!mathjaxbegin-i!! MCBcbGVxIFxsYW1iZGEgXGxlcSAx !!mathjaxend-i!!, we have that !!mathjaxbegin-i!! XGxhbWJkYSBBeCcgXGxlcSBcbGFtYmRhIGI= !!mathjaxend-i!!, that is !!mathjaxbegin-i!! QSBcbGFtYmRhIHgnIFxsZXEgXGxhbWJkYSBi !!mathjaxend-i!!. Similarly, for !!mathjaxbegin-i!! eCcn !!mathjaxend-i!!, we have that !!mathjaxbegin-i!! QSAoMS1cbGFtYmRhKSB4JyBcbGVxICgxLVxsYW1iZGEpIGI= !!mathjaxend-i!!. Summing the inequalities, we get: !!mathjaxbegin-d!! CiBBW1xsYW1iZGEgeCcgKyAoMS1cbGFtYmRhKSB4JyddIFxsZXEgW1xsYW1iZGEgKyAoMS1cbGFt YmRhKV0gYiA9IGIsCg== !!mathjaxend-d!! which means that !!mathjaxbegin-i!! XGhhdHt4fSA9IFxsYW1iZGEgeCcgKyAoMS1cbGFtYmRhKSB4Jyc= !!mathjaxend-i!! is again a solution of the original set of inequalities, thus concluding the argument.

A nice set of recent posts have done a great job detailing the remaining ways that a root user can get at kernel memory. Part of this is driven by the ideas behind UEFI Secure Boot, but they come from the same goal: making sure that the root user cannot directly subvert the running kernel. My perspective on this is toward making sure that an attacker who has gained access and then gained root privileges can t continue to elevate their access and install invisible kernel rootkits. An outline for possible attack vectors is spelled out by Matthew Gerrett s continuing useful kernel lockdown patch series. The set of attacks was examined by Tyler Borland in Bypassing modules_disabled security . His post describes each vector in detail, and he ultimately chooses MSR writing as the way to write kernel memory (and shows an example of how to re-enable module loading). One thing not mentioned is that many distros have MSR access as a module, and it s rarely loaded. If modules_disabled is already set, an attacker won t be able to load the MSR module to begin with. However, the other general-purpose vector, kexec, is still available. To prove out this method, Matthew wrote a proof-of-concept for changing kernel memory via kexec. Chrome OS is several steps ahead here, since it has hibernation disabled, MSR writing disabled, kexec disabled, modules verified, root filesystem read-only and verified, kernel verified, and firmware verified. But since not all my machines are Chrome OS, I wanted to look at some additional protections against kexec on general-purpose distro kernels that have CONFIG_KEXEC enabled, especially those without UEFI Secure Boot and Matthew s lockdown patch series. My goal was to disable kexec without needing to rebuild my entire kernel. For future kernels, I have proposed adding /proc/sys/kernel/kexec_disabled, a partner to the existing modules_disabled, that will one-way toggle kexec off. For existing kernels, things got more ugly. What options do I have for patching a running kernel? First I looked back at what I d done in the past with fixing vulnerabilities with systemtap. This ends up being a rather heavy-duty way to go about things, since you need all the distro kernel debug symbols, etc. It does work, but has a significant problem: since it uses kprobes, a root user can just turn off the probes, reverting the changes. So that s not going to work. Next I looked at ksplice. The original upstream has gone away, but there is still some work being done by Jiri Slaby. However, even with his updates which fixed various build problems, there were still more, even when building a 3.2 kernel (Ubuntu 12.04 LTS). So that s out too, which is too bad, since ksplice does exactly what I want: modifies the running kernel s functions via a module. So, finally, I decided to just do it by hand, and wrote a friendly kernel rootkit. Instead of dealing with flipping page table permissions on the normally-unwritable kernel code memory, I borrowed from PaX s KERNEXEC feature, and just turn off write protect checking on the CPU briefly to make the changes. The return values for functions on x86_64 are stored in RAX, so I just need to stuff the kexec_load syscall with mov -1, %rax; ret (-1 is EPERM):

#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include <linux/init.h>
#include <linux/module.h>
#include <linux/slab.h>
static unsigned long long_target;
static char *target;
module_param_named(syscall, long_target, ulong, 0644);
MODULE_PARM_DESC(syscall, "Address of syscall");
/* mov $-1, %rax; ret */
unsigned const char bytes[] =   0x48, 0xc7, 0xc0, 0xff, 0xff, 0xff, 0xff,
                                0xc3  ;
unsigned char *orig;
/* Borrowed from PaX KERNEXEC */
static inline void disable_wp(void)
 
        unsigned long cr0;
        preempt_disable();
        barrier();
        cr0 = read_cr0();
        cr0 &= ~X86_CR0_WP;
        write_cr0(cr0);
 
static inline void enable_wp(void)
 
        unsigned long cr0;
        cr0 = read_cr0();
        cr0  = X86_CR0_WP;
        write_cr0(cr0);
        barrier();
        preempt_enable_no_resched();
 
static int __init syscall_eperm_init(void)
 
        int i;
        target = (char *)long_target;
        if (target == NULL)
                return -EINVAL;
        /* save original */
        orig = kmalloc(sizeof(bytes), GFP_KERNEL);
        if (!orig)
                return -ENOMEM;
        for (i = 0; i < sizeof(bytes); i++)  
                orig[i] = target[i];
         
        pr_info("writing %lu bytes at %p\n", sizeof(bytes), target);
        disable_wp();
        for (i = 0; i < sizeof(bytes); i++)  
                target[i] = bytes[i];
         
        enable_wp();
        return 0;
 
module_init(syscall_eperm_init);
static void __exit syscall_eperm_exit(void)
 
        int i;
        pr_info("restoring %lu bytes at %p\n", sizeof(bytes), target);
        disable_wp();
        for (i = 0; i < sizeof(bytes); i++)  
                target[i] = orig[i];
         
        enable_wp();
        kfree(orig);
 
module_exit(syscall_eperm_exit);
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Kees Cook <kees@outflux.net>");
MODULE_DESCRIPTION("makes target syscall always return EPERM");

If I didn t want to leave an obvious indication that the kernel had been manipulated, the module could be changed to:

• not announce what it s doing
• remove the exit route to not restore the changes on module unload
• error out at the end of the init function instead of staying resident

And with this in place, it s just a matter of loading it with the address of sys_kexec_load (found via /proc/kallsyms) before I disable module loading via modprobe. Here s my upstart script:

# modules-disable - disable modules after rc scripts are done
#
description "disable loading modules"
start on stopped module-init-tools and stopped rc
task
script
        cd /root/modules/syscall_eperm
        make clean
        make
        insmod ./syscall_eperm.ko \
                syscall=0x$(egrep ' T sys_kexec_load$' /proc/kallsyms   cut -d" " -f1)
        modprobe disable
end script

And now I m safe from kexec before I have a kernel that contains /proc/sys/kernel/kexec_disabled.

2013, Kees Cook. This work is licensed under a Creative Commons Attribution-ShareAlike 3.0 License.

Last year I told you that I spent two full-time days working on Debian as a part of initiative sponsored by my current employer. This year I ve devoted these two days again for Debian. Quick summary of what I was able to do during these two days. 11 bugs, 4 lintian errors and 43 warnings were fixed. In addition 3 packages now use new source format (usually that means repackaging software from scratch). 4 uses new copyright format and the newest Standards-Version. 5 packages were updated to the newest upstream version. Changelog entries:
potrace (1.11-1) unstable; urgency=low * The Akamai Technologies paid volunteer days release.
* New upstream version.
* Completely repackaged from scratch (funny experience as usual):
- uses new copyright format
- uses debhelper compatibility level 9 w/hardening options
- uses the newest Standards-Version
- fixes 11 lintian warnings and 2 errors
* Fixes typo in manpage. (Closes: #694492) -- Bartosz Fenski Mon, 9 Dec 2013 11:23:32 +0100 makeself (2.2.0-1) unstable; urgency=low * The Akamai Technologies paid volunteer days release.
* New upstream release. (Closes: #690105)
- handles df output in more portable way (Closes: #641804)
* Repackaged from scratch.
- uses new packaging format 3.0 (Closes: #670738)
- uses new copyright format
- uses debhelper compatibility level 9
- uses the newest Standards-Version
- fixes 2 lintian errors and 6 warnings -- Bartosz Fenski Mon, 09 Dec 2013 17:32:45 +0100 dibbler (1.0.0~rc1-1) unstable; urgency=low * The Akamai Technologies paid volunteer days release.
* New upstream release candidate 1 version (Closes: #686539)
- doesn't drop dhcp session during pppd restarts (Closes: #641237)
- doesn't hang indefinitely on 'stop' (Closes: #675272)
* Calls dh --with autotools_dev to prevent build failures (Closes: 727356)
* Includes Japanese debconf translation (Closes: #718921)
* Updated Standards-Version (no changes needed)
* Uses debhelper compatibility level 9 w/hardening options
* init scripts now source init functions
* Fixes 20 lintian warnings. -- Bartosz Fenski Tue, 10 Dec 2013 10:05:56 +0100 calcurse (3.1.4-1) unstable; urgency=low * The Akamai Technologies paid volunteer days release.
* New upstream version.
* ACK previous NMU - thanks!
* Bumped Standards-Version (no changes needed) -- Bartosz Fenski Tue, 10 Dec 2013 12:22:06 +0100 ipcalc (0.41-4) unstable; urgency=low * The Akamai Technologies paid volunteer days release.
* Fixes overzealous input checking (Closes: #332468)
* Martin F Krafft removed as co-maintainer (Closes: #719098)
+ package now uses new copyright format
* Bumped Standards-Version (no changes needed) -- Bartosz Fenski Tue, 10 Dec 2013 13:05:15 +0100 msort (8.53-1) unstable; urgency=low * The Akamai Technologies paid volunteer days release.
* New upstream release.
* ACK previous NMUs, thanks!
* Switched to new source format.
* Switched to new copyright format.
* Moved patches to new quilt format and described them.
* Bumped Standards-Version (no changes needed)
* Has correct tcl/tk dependencies (Closes: #545135)
* Doesn't segfault with certain input (Closes: #630485) -- Bartosz Fenski Tue, 10 Dec 2013 16:39:44 +0100
Thank you Akamai

A new Armadillo release 3.930 came out a few days ago, with a very nice set of changes (see below). I rolled this into RcppArmadillo 0.3.930.0. However, one of these changes revealed that R shipped only the standard SVD for complex-valued matrices, and not the more performant divide-and-conquer approach. So in R builds using the default built-in Lapack, at least one CRAN package no longer built. After some back and forth, Conrad put some branching in the library to fall back to the standard SVD, and I added a built-time configuration test for an appropriate preprocessor directive used by the fallback code. This is now on which is now on CRAN and in Debian as RcppArmadillorelease 0.3.930.1, and Conrad will probably update the Armadillo page as well (though the fix is only needed with R's builtin Rlapack). Also of note is that R Core already added the missing Fortran routine zgesdd to R 3.1.0 (aka "R-devel") so this issue goes away with the next release. Also of note, I wrote up a short Rcpp Gallery post illustrating the performance gains available from divide-and-conquer SVD. The complete list of changes is below.

Changes in RcppArmadillo version 0.3.930.1 (2013-12-09)

• Upgraded to Armadillo release Version 3.930.1
  • Armadillo falls back to standard complex svd if the more performant divide-and-conquer variant is unavailable
• Added detection for Lapack library and distinguish between R's own version (withhout zgesdd) and system Lapack; a preprocessor define is set accordingly

Changes in RcppArmadillo version 0.3.930.0 (2013-12-06)

• Upgraded to Armadillo release Version 3.930 ("Dragon's Back")
  • added divide-and-conquer variant of svd_econ(), for faster SVD
  • added divide-and-conquer variant of pinv(), for faster pseudo-inverse
  • added element-wise variants of min() and max()
  • added size() based specifications of submatrix view sizes
  • added randi() for generating matrices with random integer values
  • added more intuitive specification of sort direction in sort() and sort_index()
  • added more intuitive specification of method in det(), .i(), inv() and solve()
  • added more precise timer for the wall_clock class when using C++11
• New unit tests for complex matrices and vectors

Courtesy of CRANberries, there is also a diffstat report for the most recent release As always, more detailed information is on the RcppArmadillo page. Questions, comments etc should go to the rcpp-devel mailing list off the R-Forge page.

This post by Dirk Eddelbuettel originated on his Thinking inside the box blog. Please report excessive re-aggregation in third-party for-profit settings.

krb5-sync is the software we run at Stanford to synchronize principal information from a central Heimdal realm to Active Directory, allowing users to use either a Linux-based Kerberos environment or Active Directory with the same account and password. The original intent of this release was to add a new feature to allow a subsidiary instance of an account in the MIT or Heimdal realm to be synchronized with the instance-less account in Active Directory. This allows, for example, an rra/windows instance to be used to set and maintain the password for an rra principal in Active Directory. In the process of implementing that, though, I ended up doing a significant overall of the code, since the plugin architecture was quite awkward and dated. The code now uses the MIT Kerberos data structures in a more natural and native way, since MIT Kerberos has now added direct support for plugins of this sort. Kerberos contexts and Kerberos error codes are used uniformly throughout the plugin, which provides consistent and more robust error handling and reporting. I also significantly enhanced the test suite, although it still needs more work to test the core functionality that has complex external dependencies. This release also drops support for all versions of MIT Kerberos prior to 1.9, which required an external patch; to run krb5-sync 3.0, you should upgrade to a recent version of MIT Kerberos. This allowed me to drop support for the legacy API. There are a couple of major backward-incompatible changes in this release (and both unfortunately are not handled automatically by the Debian package upgrade, since it's hard to find and safely modify KDC configuration). First, the ad_ldap_base configuration option is now mandatory when synchronizing account status and its meaning has changed. Previously, dc elements for the realm were appended to a provided partial base. Now, the complete DN of the root of the Active Directory tree should be provided. This is more flexible and more useful with a wider variety of Active Directory setups. Second, I took advantage of the backward-incompatibilities to change the module name to sync.so from krb5_sync.so, since the latter sounded weirdly redundant and verbose when installed in the Kerberos plugin directory. This will require a configuration change to the plugin configuration for the KDC or kadmin server. Also in this release are a couple of new options: ad_queue_only, which forces all changes to be queued for later processing instead of processed in real time, and syslog, which can be used to turn off the internal syslog logging of non-errors from the module. (This is mostly useful for test suites.) Now, password changes are queued on any Active Directory failure, not just a few oddly-distinguished ones. The previous behavior was rather specific to Stanford's needs, and queuing all password changes shouldn't pose any problems. Finally, the krb5-sync-backend utility program for manipulating the queued changes has been completely rewritten and is much cleaner. It now uses the Net::Remctl::Backend Perl module for command and option handling, so that module (provided with remctl 3.4 or later) must be installed. It also requires IPC::Run, which is available from CPAN. It uniformly supports a -d option to specify the queue location, and skips event files during processing that no longer exist. You can get the latest release from krb5-sync distribution page.

This release of my collection of shared C, Perl, and Autoconf code fixes a bug in all the Autoconf macros that use the lib-helper framework for optional use of libraries. The --with flag without a path would result in yes/include and yes/lib to be added to the compiler and linker paths. It also adds Autoconf probles for Cyrus SASL libraries, contributed by Julien LIE based on the INN macros. This release also adds support for KADM5_MISSING_KRB5_CONF_PARAMS to portable/kadmin.h and the test_tmpdir function to Test::RRA::Automake. The latter works the same as it does in the C and shell TAP libraries. Finally, the shared valgrind suppression file adds a suppression for the memory allocated by dlopen to store error messages for dlerror on Linux, which is apparently never freed. You can get the latest release from the rra-c-util distribution page.

Once more, I m going to FOSDEM 2014, the largest Free/Libre/Open Source Software event in Europe (5,000 attendants every year). As usual, I will be in charge of the Desktops DevRoom, together with our friends from Gnome (Christophe Fergeau), Unity (Didier Roche), Enlightenment (Philippe Caseiro) and others. See you in Brussels 1-2 February 2014! BTW, have you already submitted your talk proposal for the Desktops DevRoom? The deadline (15th December) is very close! Do not wait any more!!! See the details here: FOSDEM 2014 Desktops DevRoom Call for Talks

I ve come up with some new favorites this season. The boys and Laura were around for all three, and I am happy to report there were many kitchen smiles over these! From-Scratch Hot Chocolate There s something about hot chocolate made from scratch, with chocolate melted into milk, instead of a powder stirred in. It takes quite a bit more time, and probably has more calories, but it is quite delicious. The key to a delicious result where milk is concerned is to take things slow and keep stirring. You don t want the chocolate to scorch at the bottom of the pan. Heating up the milk before the chocolate should help things mix in more easily as well.

• Begin with 3 cups milk and 1 cup heavy whipping cream. Heat slowly over moderate to low heat, stirring periodically. Once you see bubbles start to form around the edges, it is plenty hot (or even a bit more hot than it needs to be).
• Add one cup of semisweet chocolate chips, 1 teaspoon sugar, and 1/2 tsp vanilla extract.
• Stir constantly until all the chocolate is melted and well mixed. There will still be some small bits of chocolate within, but if it is all done slowly like this, the chocolate should be pretty well melted.

The basis for this recipe was here, and it called for 2 cups milk and 2 cups half-and-half. I trust my heavy whipping cream was fine! <grin> There are also some other variations on that site. This nearly made my little cast iron kettle overflow, so next time I made a 3/4 recipe. Hot Spiced Cider We put up a Christmas tree yesterday, so I thought hot spiced cider would be perfect for the occasion. I went searching for recipes, and many of them called for cloves (which have to be sifted out later or put in a spice bag). I wasn t going to have time to delay two boys from setting up a Christmas tree long enough for that, so I found this basic recipe to work well. However, I, as usual, made some modifications ;-)

• Warm 4 cups apple cider (not juice, as the recipe suggests) in a pot.
• Add 1/2 tsp cinnamon
• Add 1/4 tsp nutmeg or allspice (I used allspice because I was mysteriously out of nutmeg, but will probably use nutmeg next time)
• Add 1 tbsp brown sugar
• Stir constantly until sufficiently dissolved. Pour immediately before drinking, as the contents will tend to separate.

Mmmmm . yum . Turkey or Chicken Noodle Soup The annual what to do with all that leftover turkey quest strikes again. I like chicken noodle soup, so why not a turkey noodle soup done the same way? Here s what I used, roughly, in my large 6-quart cast iron cooking pot (aka Dutch oven ):

• 9 cups chicken/turkey broth. Your own if you have it, or the canned variety works. Or make your own with boullion if you have it.
• 2 chopped yellow onions. (I added half a chopped red onion as well because I had it sitting around. Nobody complained, but 2.5 onions was a little much.)
• 4 tsp fresh basil or 1 tsp dried basil
• 4 tsp fresh oregano or 1 tsp dried oregano
• 1/2 tsp pepper
• 1/2 tsp salt
• 1 tsp beef bouillon
• 2 bay leaves
• 20 oz frozen mixed vegetables (I d probably add more than that next year; this wasn t quite enough)
• Plenty of wide egg noodles. The recipe I used called for 1 cup, which was laughably inadequate. I just dumped until it looked right, and then the package was almost empty so I dumped the rest in too.
• 4 cups cooked turkey or chicken, cubed (a kitchen scissors makes quick work of that)
• Two 14.5-oz cans diced tomatoes (do not drain)

Start with the broth, onion, basil, oregano, pepper, and bay leaf. Heat up the mixture and add the vegetables. Bring it to boiling, then add the uncooked noodles. Return to boiling, then reduce heat, cover, and simmer for 8 minutes. Add the turkey or chicken and diced tomatoes, and simmer until hot enough to serve. The nice thing about soups is that they freeze well and make great winter leftovers. This recipe makes quite a lot of soup; you may wish to halve it. This recipe was adapted from one in a Better Homes & Gardens cookbook.

There have been some dark days for UK coops recently the crystal Methodist and all that and I have not been able to talk about it much because of the amount of work that I want to do before the end of the year. Happily good colleagues have been writing about it and here s another good article from Kate Whittle that links to Ed Mayo and Ian Snaith who are the other two that I d suggest. http://www.cooperantics.coop/2013/12/09/co-ops-governance/ I should be back in a few days to summarise the event I attended last week.

My ASUS Transformer TF101 had suddenly started flickering in all sorts of funny colors some weeks ago. As tapping it gently on the table in the right angle made the problem go away temporarily, it was clear the problem was about a loose cable, or some other hardware connection issue. As I needed to go on a business trip the other day, I didn't look up the warranty expiration day until later that week. Then, Murphy struck: the tablet was now 2 years + 1 day old! Calling ASUS, some friendly guy there suggested I still tried to get ASUS to accept it for warranty, because the tablet had been with them last year for 5 days, so if they added that, it would still be within the warranty period. I filled out the RMA form, but one hour later the reply was they rejected it because it was out of warranty. Another guy on the phone then said they would probably only do the adding if it had been with them for maybe 10 days, or actually really 30 days, or whatever. Some googling suggested that the loose cable theory was indeed worth a try, so I took it apart. Thanks to a forum post I could then locate the display connector and fix it. Putting the case back together was actually harder than disassembling it because some plastic bits got stuck, but now everything is back to normal.

There has been a lot of discussion recently about the concept of a Basic Income (Wikipedia), largely due to the efforts to change the Swiss constitution to provide a Basic Income [1]. The concept of a Basic Income is that residents get a fixed payment without having to be sick, disabled, looking for work, or eligible for other forms of social security. A Basic Income wouldn t replace all other forms of social security, one of the most obvious examples is that sick people will often need money for medical care in additional to living expenses. Also I believe that it shouldn t be means tested in any way. I think that one of the problems with current payment schemes is that there are complex eligibility criteria which require effort for the applicant and for government agencies to prevent accidental or fraudulent over-payment. The tax rates could be raised slightly to make it revenue neutral. Newstart In Australia the main form of social security for unemployed people at the moment is called Newstart [2]. Currently Newstart payments range from a maximum of $501 per fortnight for a single person ($13,026 per annum), to a maximum of $699.90 per fortnight for someone who is a carer. The Newstart payments start to decrease if the recipient earns more than $62 per fortnight. The minimum wage in Australia is $16.37 per hour for permanent work or $20.30 for casual work [3]. So if someone works for more than 3 hours at a casual rate (and I can t imagine 4 hours a fortnight being anything other than casual) then their Newstart payments will decrease. The payment decreases are fairly significant, for every dollar that is earned about 50 cents will be deducted from the payments. That s a great incentive to either avoid opportunities to do part-time work or to do cash-only work that s outside the tax system. The most obvious way of implementing a Basic Income would be to replace Newstart. Then anyone who is in that situation would be free to just not get a job which would be OK IMHO as people who don t want to work probably wouldn t do a good job if the government forced them to get a job. People who are unemployed who want to work could work as much as they want and scale up according to what their employer asks and how much money they need. Currently the full-time minimum wage is $622.20 per week (I m not sure exactly how they get that from $16.37). That s almost 2.5* the Newstart allowance for a single person (but less than twice the Newstart allowance for a carer). While Newstart (and the other forms of social security) don t provide a great income, it seems that the difference between Newstart and the minimum wage isn t that great particularly when you consider that working involves some expenses for travel etc. There doesn t seem to be a great financial incentive for someone to leave Newstart and get a minimum wage job. People Who Want Social Security Some people think it s great to get government payments while others find it embarrassing to need such payments and won t necessarily apply if they are eligible. I think that the current system of forcing people to apply for social security is a way of discouraging people who find themselves unexpectedly in a difficult situation but doesn t discourage people who are happy not to work. This seems to effectively reduce the incidence of payments to the people who most tax-payers would regard as the most worthy recipients. Economics Charles Stross wrote about some ideas related to this [4]. He suggests that as the workforce participation has been steadily reducing due to technology we should move to a social model that isn t based around working to live but working to buy luxuries that aren t covered by the Basic Income. One of the many economic changes related to a Basic Income is that the minimum wage could be smaller than it might otherwise be. For example if the minimum wage was decreased by the same amount that the Basic Income provided then the minimum income would remain the same while employers would pay less, this would affect the viability of certain types of contract work web sites if they were subject to minimum wage laws (currently they just ignore the minimum wage laws by paying based on job completion instead of hours worked). I don t think that the minimum wage should decrease that much though, currently employers are able to run viable businesses with the minimum wage laws and I don t think that a Basic Income should be used as a way of helping corporations avoid paying their employees. If we had a Basic Income then there s many ways that it could be used to stabilise the economy. If people could pay their rent even if they lost their job then a down-turn in one area of the economy wouldn t immediately affect other areas. Also if rent payments were deducted automatically from an account used to receive the Basic Income then landlords would be more likely to rent to poor people as they could be guaranteed to receive rent payments (it would be easy to have a contractual agreement for rent to take priority and have bank computers enforce that). The Implementation Problem I don t think that my idea would have any significant negative effects. It wouldn t decrease government revenues if tax was adjusted accordingly. It wouldn t make people stop working as people who don t want to work already avoid it. It would help people who are out of work to get work by reducing the barriers to entry in terms of paperwork and of unreasonable cuts to Newstart making it bad value to take part time work. I think that the big problem with implementing it is people who want to prevent poor people from having opportunities. They want to reduce social security and minimum wages even though such changes will in the long run only give less tax revenue and greater expense in law enforcement. It seems rather ironic that such hostility often comes from people at the low end of the middle class whos jobs are most likely to be at risk from new technology. As on-going technological development reduces the number of workers that are required to keep things running we need to have some form of payment to the people who aren t doing enough work to survive. A decent Basic Income is a much better option than giving Newstart payments and forcing a significant portion of the population into a degrading search for jobs that don t exist. As that s the inevitable future I think we should make political changes to deal with it sooner rather than later. However a Basic Income might be implemented now it s surely going to be a lot better than what might happen if we wait until the majority of the population are unemployed before doing something about it.

• [1] http://tinyurl.com/mwemen5
  
• [2] http://www.humanservices.gov.au/customer/services/centrelink/newstart-allowance
• [3] http://www.fairwork.gov.au/PAY/NATIONAL-MINIMUM-WAGE/pages/default.aspx
• [4] http://tinyurl.com/mjq3dwl

I previously wrote about the financial value of a university degree [1], my general conclusion is that the value is decreasing for most fields of employment that don t have a legal requirement for a degree. In the past I wrote about some ideas for a home university [2], basically extending the home-schooling concept to a university level. I recently read John Scalzi s post about being poor [3], many of the comments address the difficulty of getting to college and how it impacts career possibilities. From reading that it seems that my ideas about a home university are mostly based around what middle-class people can afford. Also getting a job afterwards will probably be a lot easier for someone who was born into the middle classes. It seems to me that a large part of the problem with the university system is the expectation that they will both provide for academic research and train people for jobs. Dr. David Helfand has some great ideas for running a university to give the higher education that a university is supposed to provide rather than the work training that most universities actually provide [4]. His ideas aren t theoretical, they have been implemented and proven to work. Note that Dr Helfand s talk starts slowly, the second half is the best (for those of you with short attention spans). The fact that most people think of a university degree in terms of getting a job seems to be a failure of the university system to fulfill it s original aim. If Dr Helfand s ideas take off then it would really address the problem of universities not educating people. But that still leaves the issue of job training. Is a Degree Mandatory? I think that to some degree people expect that a university degree is necessary job training even when it isn t. I wonder what would happen if it was generally agreed that the right thing to do was to search for a job between the end of high school and the start of university, then anyone who got a suitable offer could defer their university course and see what career success they could achieve without it. When I was at school the general idea was that after completing year 12 everyone just had a holiday until the start of university as the entire point of school was to get into university. While hiring managers prefer candidates who have degrees they also prefer to hire people who will accept a lower salary, so hiring an 18yo with no degree may give better value than a 21yo who has a degree. I believe that making university degrees more accessible has reduced inequality which is a good thing. But making degrees mandatory (which is widely believed by high school students and thus is the situation that they have to deal with) contributes to greater inequality. While university doesn t cost much by middle-class standards it is still expensive for poor people. If a university degree wasn t considered to be mandatory then the number of people employed to teach at a university level would be smaller. This would hopefully mean that the average skill of university lecturers would increase (I hope that the least skillful lecturers would be the ones to find work elsewhere).

• [1] http://etbe.coker.com.au/2012/06/14/financial-value-degree/
• [2] http://etbe.coker.com.au/2007/10/04/ideas-for-a-home-university/
• [3] http://whatever.scalzi.com/2005/09/03/being-poor/
• [4] http://tedxtalks.ted.com/video/Designing-a-university-for-the

The recent news that openSUSE considers btrfs safe for users prompted me to consider using it. And indeed I did. I was already familiar with zfs, so considered this a good opportunity to experiment with btrfs. btrfs makes an intriguing filesystem for all sorts of workloads. The benefits of btrfs and zfs are well-documented elsewhere. There are a number of features btrfs has that zfs lacks. For instance:

• The ability to shrink a device that s a member of a filesystem/pool
• The ability to remove a device from a filesystem/pool entirely, assuming enough free space exists elsewhere for its data to be moved over.
• Asynchronous deduplication that imposes neither a synchronous performance hit nor a heavy RAM burden
• Copy-on-write copies down to the individual file level with cp --reflink
• Live conversion of data between different profiles (single, dup, RAID0, RAID1, etc)
• Live conversion between on-the-fly compression methods, including none at all
• Numerous SSD optimizations, including alignment and both synchronous and asynchronous TRIM options
• Proper integration with the VM subsystem
• Proper support across the many Linux architectures, including 32-bit ones (zfs is currently only flagged stable on amd64)
• Does not require excessive amounts of RAM

The feature set of ZFS that btrfs lacks is well-documented elsewhere, but there are a few odd btrfs missteps:

• There is no way to see how much space subvolume/filesystem is using without turning on quotas. Even then, it is cumbersome and not reported with df like it should be.
• When a maxmium size for a subvolume is set via a quota, it is not reported via df; applications have no idea when they are about to hit the maximum size of a filesystem.

btrfs would be fine if it worked reliably. I should say at the outset that I have never lost any data due to it, but it has caused enough kernel panics that I ve lost count. I several times had a file that produced a panic when I tried to delete it, several times when it took more than 12 hours to unmount a btrfs filesystem, behaviors where hardlink-heavy workloads take days longer to complete than on zfs or ext4, and that s just the ones I wrote about. I tried to use btrfs balance to change the metadata allocation on the filesystem, and never did get it to complete; it seemed to go into an endless I/O pattern after the first 1GB of metadata and never got past that. I didn t bother trying the live migration of data from one disk to another on this filesystem. I wanted btrfs to work. I really, really did. But I just can t see it working. I tried it on my laptop, but had to turn of CoW on my virtual machine s disk because of the rm bug. I tried it on my backup devices, but it was unusable there due to being so slow. (Also, the hardlink behavior is broken by default and requires btrfstune -r. Yipe.) At this point, I don t think it is really all that worth bothering with. I think the SuSE decision is misguided and ill-informed. btrfs will be an awesome filesystem. I am quite sure it will, and will in time probably displace zfs as the most advanced filesystem out there. But that time is not yet here. In the meantime, I m going to build a Debian Live Rescue CD with zfsonlinux on it. Because I don t ever set up a system I can t repair.

I spent yesterday at the very enjoyable Big Data Summit held at the University of Illinois Research Park at the edge of the University of Illinois at Urbana-Champaign. campus. My (short) presentation was part of a panel session on R and Big Data which Doug Simpson of the UIUC Statistics department had put together very well. We heard from a vendor / technology provider with Christopher Nguyen from Adatao talking about their "Big R", from industry with Andy Stevens talking about a number of some real-life challenges with big data at John Deere, from academia with Jonathon Greenberg talking about R and HPC for geospatial research and I added a few short comments and links about R, HPC and Rcpp. My few slides are now up on my talks / presentations page. Overall, a good day with a number of interesting presentations and of course a number of engaging hallway discussions.

This post by Dirk Eddelbuettel originated on his Thinking inside the box blog. Please report excessive re-aggregation in third-party for-profit settings.

Hello For more 10 years, opening a https connection throught a proxy was not possible
with LWP::UserAgent. Thanks to Steffen Ullrich, this bug is now fixed in LWP::UserAgent and LWP::Protocol::https repositories. In Debian, I ve updated libwww-perl 6.05-2 and liblwp-protocol-https-perl 6.04-2 to include the same patches. This fix is now available in Debian unstable. See my previous blog for more details on this story. All the best
Tagged: debian, https_proxy, Perl