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2005-05-19Merge with master.kernel.org:/pub/scm/linux/kernel/git/torvalds/linux-2.6.gitDavid Woodhouse
2005-05-19AUDIT: Quis Custodiet Ipsos Custodes?David Woodhouse
Nobody does. Really, it gets very silly if auditd is recording its own actions. Signed-off-by: David Woodhouse <dwmw2@infradead.org>
2005-05-19AUDIT: Send netlink messages from a separate kernel threadDavid Woodhouse
netlink_unicast() will attempt to reallocate and will free messages if the socket's rcvbuf limit is reached unless we give it an infinite timeout. So do that, from a kernel thread which is dedicated to spewing stuff up the netlink socket. Signed-off-by: David Woodhouse <dwmw2@infradead.org>
2005-05-19AUDIT: Clean up logging of untrusted stringsSteve Grubb
* If vsnprintf returns -1, it will mess up the sk buffer space accounting. This is fixed by not calling skb_put with bogus len values. * audit_log_hex was a loop that called audit_log_vformat with %02X for each character. This is very inefficient since conversion from unsigned character to Ascii representation is essentially masking, shifting, and byte lookups. Also, the length of the converted string is well known - it's twice the original. Fixed by rewriting the function. * audit_log_untrustedstring had no comments. This makes it hard for someone to understand what the string format will be. * audit_log_d_path was never fixed to use untrustedstring. This could mess up user space parsers. This was fixed to make a temp buffer, call d_path, and log temp buffer using untrustedstring. From: Steve Grubb <sgrubb@redhat.com> Signed-off-by: David Woodhouse <dwmw2@infradead.org>
2005-05-18AUDIT: Treat all user messages identically.David Woodhouse
It's silly to have to add explicit entries for new userspace messages as we invent them. Just treat all messages in the user range the same. Signed-off-by: David Woodhouse <dwmw2@infradead.org>
2005-05-17[PATCH] Driver Core: pm diagnostics update, check for errorsDavid Brownell
This patch includes various tweaks in the messaging that appears during system pm state transitions: * Warn about certain illegal calls in the device tree, like resuming child before parent or suspending parent before child. This could happen easily enough through sysfs, or in some cases when drivers use device_pm_set_parent(). * Be more consistent about dev_dbg() tracing ... do it for resume() and shutdown() too, and never if the driver doesn't have that method. * Say which type of system sleep state is being entered. Except for the warnings, these only affect debug messaging. Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Acked-by: Pavel Machek <pavel@ucw.cz> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2005-05-17[PATCH] profile.c: `schedule' parsing fixWilliam Lee Irwin III
profile=schedule parsing is not quite what it should be. First, str[7] is 'e', not ',', but then even if it did fall through, prof_on = SCHED_PROFILING would be clobbered inside if (get_option(...)) So a small amount of rearrangement is done in this patch to correct it. Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-05-17[PATCH] add_preferred_console() build fixMatt Mackall
Move add_preferred_console out of CONFIG_PRINTK so serial console does the right thing. Signed-off-by: Matt Mackall <mpm@selenic.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-05-17[PATCH] spurious interrupt fixZhang, Yanmin
On my IA64 machine, after kernel 2.6.12-rc3 boots, an edge-triggered interrupt (IRQ 46) keeps triggered over and over again. There is no IRQ 46 interrupt action handler. It has lots of impact on performance. Kernel 2.6.10 and its prior versions have no the problem. Basically, kernel 2.6.10 will mask the spurious edge interrupt if the interrupt is triggered for the second time and its status includes IRQ_DISABLE|IRQ_PENDING. Originally, IA64 kernel has its own specific _irq_desc definitions in file arch/ia64/kernel/irq.c. The definition initiates _irq_desc[irq].status to IRQ_DISABLE. Since kernel 2.6.11, it was moved to architecture independent codes, i.e. kernel/irq/handle.c, but kernel/irq/handle.c initiates _irq_desc[irq].status to 0 instead of IRQ_DISABLE. Signed-off-by: Zhang Yanmin <yanmin.zhang@intel.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-05-17AUDIT: Capture sys_socketcall arguments and sockaddrs David Woodhouse
Signed-off-by: David Woodhouse <dwmw2@infradead.org>
2005-05-13AUDIT: fix max_t thinko.David Woodhouse
Der... if you use max_t it helps if you give it a type. Note to self: Always just apply the tested patches, don't try to port them by hand. You're not clever enough. Signed-off-by: David Woodhouse <dwmw2@infradead.org>
2005-05-13AUDIT: Fix some spelling errorsSteve Grubb
I'm going through the kernel code and have a patch that corrects several spelling errors in comments. From: Steve Grubb <sgrubb@redhat.com> Signed-off-by: David Woodhouse <dwmw2@infradead.org>
2005-05-13AUDIT: Add message types to audit recordsSteve Grubb
This patch adds more messages types to the audit subsystem so that audit analysis is quicker, intuitive, and more useful. Signed-off-by: Steve Grubb <sgrubb@redhat.com> --- I forgot one type in the big patch. I need to add one for user space originating SE Linux avc messages. This is used by dbus and nscd. -Steve --- Updated to 2.6.12-rc4-mm1. -dwmw2 Signed-off-by: David Woodhouse <dwmw2@infradead.org>
2005-05-13AUDIT: Round up audit skb expansion to AUDIT_BUFSIZ.David Woodhouse
Otherwise, we will be repeatedly reallocating, even if we're only adding a few bytes at a time. Pointed out by Steve Grubb. Signed-off-by: David Woodhouse <dwmw2@infradead.org>
2005-05-11Add audit_log_typeChris Wright
Add audit_log_type to allow callers to specify type and pid when logging. Convert audit_log to wrapper around audit_log_type. Could have converted all audit_log callers directly, but common case is default of type AUDIT_KERNEL and pid 0. Update audit_log_start to take type and pid values when creating a new audit_buffer. Move sequences that did audit_log_start, audit_log_format, audit_set_type, audit_log_end, to simply call audit_log_type directly. This obsoletes audit_set_type and audit_set_pid, so remove them. Signed-off-by: Chris Wright <chrisw@osdl.org> Signed-off-by: David Woodhouse <dwmw2@infradead.org>
2005-05-11Move ifdef CONFIG_AUDITSYSCALL to headerChris Wright
Remove code conditionally dependent on CONFIG_AUDITSYSCALL from audit.c. Move these dependencies to audit.h with the rest. Signed-off-by: Chris Wright <chrisw@osdl.org> Signed-off-by: David Woodhouse <dwmw2@infradead.org>
2005-05-11Audit requires CONFIG_NETChris Wright
Audit now actually requires netlink. So make it depend on CONFIG_NET, and remove the inline dependencies on CONFIG_NET. Signed-off-by: Chris Wright <chrisw@osdl.org> Signed-off-by: David Woodhouse <dwmw2@infradead.org>
2005-05-11AUDIT: Properly account for alignment difference in nlmsg_len.Chris Wright
Signed-off-by: Chris Wright <chrisw@osdl.org> Signed-off-by: David Woodhouse <dwmw2@infradead.org>
2005-05-10AUDIT: Fix abuse of va_args. David Woodhouse
We're not allowed to use args twice; we need to use va_copy. Signed-off-by: David Woodhouse <dwmw2@infradead.org>
2005-05-10AUDIT: pass size argument to audit_expand().David Woodhouse
Let audit_expand() know how much it's expected to grow the buffer, in the case that we have that information to hand. Signed-off-by: David Woodhouse <dwmw2@infradead.org>
2005-05-10AUDIT: Fix reported length of audit messages.Steve Grubb
We were setting nlmsg_len to skb->len, but we should be subtracting the size of the header. From: Steve Grubb <sgrubb@redhat.com> Signed-off-by: David Woodhouse <dwmw2@infradead.org>
2005-05-06AUDIT: Honour gfp_mask in audit_buffer_alloc()David Woodhouse
Signed-off-by: David Woodhouse <dwmw2@infradead.org>
2005-05-06AUDIT: buffer audit msgs directly to skbChris Wright
Drop the use of a tmp buffer in the audit_buffer, and just buffer directly to the skb. All header data that was temporarily stored in the audit_buffer can now be stored directly in the netlink header in the skb. Resize skb as needed. This eliminates the extra copy (and the audit_log_move function which was responsible for copying). Signed-off-by: Chris Wright <chrisw@osdl.org> Signed-off-by: David Woodhouse <dwmw2@infradead.org>
2005-05-06AUDIT: expand audit tmp buffer as neededChris Wright
Introduce audit_expand and make the audit_buffer use a dynamic buffer which can be resized. When audit buffer is moved to skb it will not be fragmented across skb's, so we can eliminate the sklist in the audit_buffer. During audit_log_move, we simply copy the full buffer into a single skb, and then audit_log_drain sends it on. Signed-off-by: Chris Wright <chrisw@osdl.org> Signed-off-by: David Woodhouse <dwmw2@infradead.org>
2005-05-06AUDIT: Add helper functions to allocate and free audit_buffers.Chris Wright
Signed-off-by: Chris Wright <chrisw@osdl.org> Signed-off-by: David Woodhouse <dwmw2@infradead.org>
2005-05-06The attached patch addresses the problem with getting the audit daemon Steve Grubb
shutdown credential information. It creates a new message type AUDIT_TERM_INFO, which is used by the audit daemon to query who issued the shutdown. It requires the placement of a hook function that gathers the information. The hook is after the DAC & MAC checks and before the function returns. Racing threads could overwrite the uid & pid - but they would have to be root and have policy that allows signalling the audit daemon. That should be a manageable risk. The userspace component will be released later in audit 0.7.2. When it receives the TERM signal, it queries the kernel for shutdown information. When it receives it, it writes the message and exits. The message looks like this: type=DAEMON msg=auditd(1114551182.000) auditd normal halt, sending pid=2650 uid=525, auditd pid=1685 Signed-off-by: Steve Grubb <sgrubb@redhat.com> Signed-off-by: David Woodhouse <dwmw2@infradead.org>
2005-05-05[PATCH] correctly name the Shell sortDomen Puncer
As per http://www.nist.gov/dads/HTML/shellsort.html, this should be referred to as a Shell sort. Shell-Metzner is a misnomer. Signed-off-by: Daniel Dickman <didickman@yahoo.com> Signed-off-by: Domen Puncer <domen@coderock.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-05-05[PATCH] setitimer timer expires too earlyPaulo Marques
It seems that the code responsible for this is in kernel/itimer.c:126: p->signal->real_timer.expires = jiffies + interval; add_timer(&p->signal->real_timer); If you request an interval of, lets say 900 usecs, the interval given by timeval_to_jiffies will be 1. If you request this when we are half-way between two timer ticks, the interval will only give 400 usecs. If we want to guarantee that we never ever give intervals less than requested, the simple solution would be to change that to: p->signal->real_timer.expires = jiffies + interval + 1; This however will produce pathological cases, like having a idle system being requested 1 ms timeouts will give systematically 2 ms timeouts, whereas currently it simply gives a few usecs less than 1 ms. The complex (and more computationally expensive) solution would be to check the gettimeofday time, and compute the correct number of jiffies. This way, if we request a 300 usecs timer 200 usecs inside the timer tick, we can wait just one tick, but not if we are 800 usecs inside the tick. This would also mean that we would have to lock preemption during these computations to avoid races, etc. I've searched the archives but couldn't find this particular issue being discussed before. Attached is a patch to do the simple solution, in case anybody thinks that it should be used. Signed-Off-By: Paulo Marques <pmarques@grupopie.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-05-05[PATCH] kprobes: Allow multiple kprobes at the same addressAnanth N Mavinakayanahalli
Allow registration of multiple kprobes at an address in an architecture agnostic way. Corresponding handlers will be invoked in a sequence. But, a kprobe and a jprobe can't (yet) co-exist at the same address. Signed-off-by: Ananth N Mavinakayanahalli <amavin@redhat.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-05-05[PATCH] Kprobes: Oops! in unregister_kprobe()Prasanna S Panchamukhi
kernel oops! when unregister_kprobe() is called on a non-registered kprobe. This patch fixes the above problem by checking if the probe exists before unregistering. Signed-off-by: Prasanna S Panchamukhi <prasanna@in.ibm.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-05-05[PATCH] ppc64: remove hidden -fno-omit-frame-pointer for schedule.cAnton Blanchard
While looking at code generated by gcc4.0 I noticed some functions still had frame pointers, even after we stopped ppc64 from defining CONFIG_FRAME_POINTER. It turns out kernel/Makefile hardwires -fno-omit-frame-pointer on when compiling schedule.c. Create CONFIG_SCHED_NO_NO_OMIT_FRAME_POINTER and define it on architectures that dont require frame pointers in sched.c code. (akpm: blame me for the name) Signed-off-by: Anton Blanchard <anton@samba.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-05-05[PATCH] ppc32: platform-specific functions missing from kallsyms.David Woodhouse
The PPC32 kernel puts platform-specific functions into separate sections so that unneeded parts of it can be freed when we've booted and actually worked out what we're running on today. This makes kallsyms ignore those functions, because they're not between _[se]text or _[se]inittext. Rather than teaching kallsyms about the various pmac/chrp/etc sections, this patch adds '_[se]extratext' markers for kallsyms. Signed-off-by: David Woodhouse <dwmw2@infradead.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-05-05Merge with master.kernel.org:/pub/scm/linux/kernel/git/torvalds/linux-2.6.gitDavid Woodhouse
2005-05-04Automatic merge of ↵Linus Torvalds
rsync://rsync.kernel.org/pub/scm/linux/kernel/git/aegl/linux-2.6.git
2005-05-03[NETLINK]: Synchronous message processing.Herbert Xu
Let's recap the problem. The current asynchronous netlink kernel message processing is vulnerable to these attacks: 1) Hit and run: Attacker sends one or more messages and then exits before they're processed. This may confuse/disable the next netlink user that gets the netlink address of the attacker since it may receive the responses to the attacker's messages. Proposed solutions: a) Synchronous processing. b) Stream mode socket. c) Restrict/prohibit binding. 2) Starvation: Because various netlink rcv functions were written to not return until all messages have been processed on a socket, it is possible for these functions to execute for an arbitrarily long period of time. If this is successfully exploited it could also be used to hold rtnl forever. Proposed solutions: a) Synchronous processing. b) Stream mode socket. Firstly let's cross off solution c). It only solves the first problem and it has user-visible impacts. In particular, it'll break user space applications that expect to bind or communicate with specific netlink addresses (pid's). So we're left with a choice of synchronous processing versus SOCK_STREAM for netlink. For the moment I'm sticking with the synchronous approach as suggested by Alexey since it's simpler and I'd rather spend my time working on other things. However, it does have a number of deficiencies compared to the stream mode solution: 1) User-space to user-space netlink communication is still vulnerable. 2) Inefficient use of resources. This is especially true for rtnetlink since the lock is shared with other users such as networking drivers. The latter could hold the rtnl while communicating with hardware which causes the rtnetlink user to wait when it could be doing other things. 3) It is still possible to DoS all netlink users by flooding the kernel netlink receive queue. The attacker simply fills the receive socket with a single netlink message that fills up the entire queue. The attacker then continues to call sendmsg with the same message in a loop. Point 3) can be countered by retransmissions in user-space code, however it is pretty messy. In light of these problems (in particular, point 3), we should implement stream mode netlink at some point. In the mean time, here is a patch that implements synchronous processing. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2005-05-03[patch] MCA recovery module undefined symbol fixRuss Anderson
The patch "MCA recovery improvements" added do_exit to mca_drv.c. That's fine when the mca recovery code is built in the kernel (CONFIG_IA64_MCA_RECOVERY=y) but breaks building the mca recovery code as a module (CONFIG_IA64_MCA_RECOVERY=m). Most users are currently building this as a module, as loading and unloading the module provides a very convenient way to turn on/off error recovery. This patch exports do_exit, so mca_drv.c can build as a module. Signed-off-by: Russ Anderson (rja@sgi.com) Signed-off-by: Tony Luck <tony.luck@intel.com>
2005-05-03[PATCH] add new audit data to last skbChris Wright
When adding more formatted audit data to an skb for delivery to userspace, the kernel will attempt to reuse an skb that has spare room. However, if the audit message has already been fragmented to multiple skb's, the search for spare room in the skb uses the head of the list. This will corrupt the audit message with trailing bytes being placed midway through the stream. Fix is to look at the end of the list. Signed-off-by: Chris Wright <chrisw@osdl.org> Signed-off-by: David Woodhouse <dwmw2@infradead.org>
2005-05-03Merge with master.kernel.org:/pub/scm/linux/kernel/git/torvalds/linux-2.6.gitDavid Woodhouse
2005-05-01[PATCH] make lots of things staticAdrian Bunk
Another large rollup of various patches from Adrian which make things static where they were needlessly exported. Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-05-01[PATCH] DocBook: fix some descriptionsMartin Waitz
Some KernelDoc descriptions are updated to match the current code. No code changes. Signed-off-by: Martin Waitz <tali@admingilde.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-05-01[PATCH] DocBook: changes and extensions to the kernel documentationPavel Pisa
I have recompiled Linux kernel 2.6.11.5 documentation for me and our university students again. The documentation could be extended for more sources which are equipped by structured comments for recent 2.6 kernels. I have tried to proceed with that task. I have done that more times from 2.6.0 time and it gets boring to do same changes again and again. Linux kernel compiles after changes for i386 and ARM targets. I have added references to some more files into kernel-api book, I have added some section names as well. So please, check that changes do not break something and that categories are not too much skewed. I have changed kernel-doc to accept "fastcall" and "asmlinkage" words reserved by kernel convention. Most of the other changes are modifications in the comments to make kernel-doc happy, accept some parameters description and do not bail out on errors. Changed <pid> to @pid in the description, moved some #ifdef before comments to correct function to comments bindings, etc. You can see result of the modified documentation build at http://cmp.felk.cvut.cz/~pisa/linux/lkdb-2.6.11.tar.gz Some more sources are ready to be included into kernel-doc generated documentation. Sources has been added into kernel-api for now. Some more section names added and probably some more chaos introduced as result of quick cleanup work. Signed-off-by: Pavel Pisa <pisa@cmp.felk.cvut.cz> Signed-off-by: Martin Waitz <tali@admingilde.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-05-01[PATCH] convert that currently tests _NSIG directly to use valid_signal()Jesper Juhl
Convert most of the current code that uses _NSIG directly to instead use valid_signal(). This avoids gcc -W warnings and off-by-one errors. Signed-off-by: Jesper Juhl <juhl-lkml@dif.dk> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-05-01[PATCH] consolidate sys_shmatStephen Rothwell
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-05-01[PATCH] Change synchronize_kernel to _rcu and _schedPaul E. McKenney
This patch changes calls to synchronize_kernel(), deprecated in the earlier "Deprecate synchronize_kernel, GPL replacement" patch to instead call the new synchronize_rcu() and synchronize_sched() APIs. Signed-off-by: Paul E. McKenney <paulmck@us.ibm.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-05-01[PATCH] Deprecate synchronize_kernel, GPL replacementPaul E. McKenney
The synchronize_kernel() primitive is used for quite a few different purposes: waiting for RCU readers, waiting for NMIs, waiting for interrupts, and so on. This makes RCU code harder to read, since synchronize_kernel() might or might not have matching rcu_read_lock()s. This patch creates a new synchronize_rcu() that is to be used for RCU readers and a new synchronize_sched() that is used for the rest. These two new primitives currently have the same implementation, but this is might well change with additional real-time support. Both new primitives are GPL-only, the old primitive is deprecated. Signed-off-by: Paul E. McKenney <paulmck@us.ibm.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-05-01[PATCH] kernel/rcupdate.c: make the exports EXPORT_SYMBOL_GPLPaul E. McKenney
The gpl exports need to be put back. Moving them to GPL -- but in a measured manner, as I proposed on this list some months ago -- is fine. Changing these particular exports precipitously is most definitely -not- fine. Here is my earlier proposal: http://marc.theaimsgroup.com/?l=linux-kernel&m=110520930301813&w=2 See below for a patch that puts the exports back, along with an updated version of my earlier patch that starts the process of moving them to GPL. I will also be following this message with RFC patches that introduce two (EXPORT_SYMBOL_GPL) interfaces to replace synchronize_kernel(), which then becomes deprecated. Signed-off-by: <paulmck@us.ibm.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-05-01[PATCH] clean up kernel messagesMatt Mackall
Arrange for all kernel printks to be no-ops. Only available if CONFIG_EMBEDDED. This patch saves about 375k on my laptop config and nearly 100k on minimal configs. Signed-off-by: Matt Mackall <mpm@selenic.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-05-01[PATCH] nice and rt-prio rlimitsMatt Mackall
Add a pair of rlimits for allowing non-root tasks to raise nice and rt priorities. Defaults to traditional behavior. Originally written by Chris Wright. The patch implements a simple rlimit ceiling for the RT (and nice) priorities a task can set. The rlimit defaults to 0, meaning no change in behavior by default. A value of 50 means RT priority levels 1-50 are allowed. A value of 100 means all 99 privilege levels from 1 to 99 are allowed. CAP_SYS_NICE is blanket permission. (akpm: see http://www.uwsg.iu.edu/hypermail/linux/kernel/0503.1/1921.html for tips on integrating this with PAM). Signed-off-by: Matt Mackall <mpm@selenic.com> Acked-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-05-01[PATCH] use smp_mb/wmb/rmb where possibleakpm@osdl.org
Replace a number of memory barriers with smp_ variants. This means we won't take the unnecessary hit on UP machines. Signed-off-by: Anton Blanchard <anton@samba.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-04-29Remove bogus BUG() in kernel/exit.cLinus Torvalds
It's old sanity checking that may have been useful for debugging, but is just bogus these days. Noticed by Mattia Belletti.