Commit Graph
16 Commits
Author SHA1 Message Date
jschoubben c433e76de2 Judge a granted group by number, grant nothing a group cannot write, and keep the look bounded (hq ADR 0312, issue 537 review)
mesh/merge-gate pass: builds mesh-host → ace, g14, novox, shanks; no bus step; every machine composes with the change as it did without (4 of 4 compose)
mesh/repo-check pass: its merge-check.sh passed
mesh/delivery delivered
The engine is built without cgo, so a check by name missed a root group a name
service holds or one number carrying another name: the root groups are resolved
to numbers (now with kmem and shadow) and a number named nothing is refused for
containers too. A group without write is granted nothing (§2). The look reads
each path off the lock within five seconds, so a dead network mount cannot stop
every health statement. A grant's account may not start with a dash. A group a
record leaves for another asker is handed to it, so it is still taken back when
the last asker goes (§5). The scheduler skips paths issue 339's guard refuses.
2026-10-12 12:53:42 +02:00
jschoubben f311fa36dc The setuid walk is paced before each file too, so a large directory is not read blind (review of issue 433)
mesh/merge-gate pass: builds mesh-host → ace, g14, novox, shanks; no bus step; every machine composes with the change as it did without (4 of 4 compose)
mesh/repo-check pass: its merge-check.sh passed
mesh/delivery delivered
A file's own details (lstat) may be read from the disk as a directory is,
so a directory of tens of thousands of files was read without a look and
the header's promise that no burst is longer than PaceLook did not hold.
The walk now asks the pacer before each file as well; the 250 ms gate
makes that a clock read per file. A test with one directory of twenty
files fails without it. The clock is read once after a run of pauses,
and the constants test says that it guards the constants only.
2026-10-11 01:55:39 +02:00
jschoubben 30242197fa The paced walk keeps a tenth of the time, and reads the pressure since its last look (review of issue 433)
mesh/merge-gate pass: builds mesh-host → ace, g14, novox, shanks; no bus step; every machine composes with the change as it did without (4 of 4 compose)
mesh/repo-check pass: its merge-check.sh passed
mesh/delivery superseded: a newer head of the same pull request
The review of #79 found that pacing alone brought back issue 361's
fault. The control-node's own I/O pressure sits near the 10 % bound with
no walk running, so a walk that paused 30 s for every 250 ms it read
would read 0.8 % of the time: a 16-minute walk would take some 32 hours,
outlive the age a search judges for, and be begun again at an engine
restart, leaving the machine unjudged.

A run of pauses is now at most nine times as long as the walk read since
the one before, so the walk keeps at least a tenth of the time whatever
the pressure, and takes at most ten times as long as unpaced: about
2.7 hours for the 16-minute walk, inside the 12 hours the controller
waits quietly. A test ties the bound to rootsearch.Quiet.

The pressure is the share of the time since the last look in which some
task waited on I/O, from PSI's cumulative counter, not its ten-second
average, which the kernel moves only every two seconds. A pause is
500 ms, then the pressure is looked at again.

The engine's walker is built in one place, engineWalker, and a test
fails if it is not paced by /proc/pressure/io. What the walk cannot read
is said through the search's own channel (the cache's Say), as the rest
of the search is, with what it means for the disk.
2026-10-11 01:53:25 +02:00
jschoubben 8f7db549ae The setuid walk paces itself by the machine's I/O pressure (issue 433)
mesh/merge-gate pass: builds mesh-host → ace, g14, novox, shanks; no bus step; every machine composes with the change as it did without (4 of 4 compose)
mesh/repo-check pass: its merge-check.sh passed
mesh/delivery superseded: a newer head of the same pull request
The walk for setuid programs is put in the idle I/O class so it yields
to everything else, but only a scheduler that schedules by class (BFQ)
honours that. The control-node's disks run mq-deadline, which does not,
so the walk read at full priority. On 2026-10-11 the walk started at
01:27, right after the engine applied a new controller, and ran sixteen
minutes; it kept two spinning disks saturated, the bus whose store
shares them stalled for half a minute twice, and the controller lost
its lease and restarted each time.

The walk now also paces itself by PSI, which reads the same whatever
the scheduler: before it reads a directory, while some task has waited
on I/O for more than 10 % of the last ten seconds, it pauses two
seconds at a time. It looks at most every 250 ms, pauses at most 30 s
in a row and then reads one more directory, so a machine that is never
quiet is walked slowly but still judged. Its own reads count in the
pressure, so on an otherwise idle machine it holds the disk below the
bound. Pressure it cannot read pauses nothing, and is said once.

A paced walk finds what an unpaced one finds; a walk ended while it
pauses is an incomplete walk, never one that found nothing.
2026-10-11 01:47:43 +02:00
jochen 0b4c86e3be Count a setuid find only where the account can execute it, read at every judgement (hq issue 361)
mesh/merge-gate pass: builds mesh-host → ace, g14, novox, shanks; no bus step; every machine composes with the change as it did without (4 of 4 compose)
mesh/repo-check pass: its merge-check.sh passed
mesh/delivery delivered
The two finds on the control-node sit in the operator's home of mode 0700, which the agent account cannot
search. The search keeps every find; each judgement reads the modes on the way again, since an account can
open its own home without root. A find in a home is said by count, its path in the journal alone. Also
from review: a checkpoint racing SearchNow forgets the walk it just kept, and a walk kept by an older engine
says its counts as lower bounds.
2026-10-10 02:00:10 +02:00
jochen 8e79403c21 Show how far the setuid search got, and start a fresh one when the terminal asks (hq issue 361)
mesh/merge-gate pass: builds mesh-host → ace, g14, novox, shanks; no bus step; every machine composes with the change as it did without (4 of 4 compose)
mesh/repo-check fail: its merge-check.sh failed: --- FAIL: TestNatsAnEnrolmentWithNoReplyAddressIsNotAnswered (0.00s)
mesh/delivery superseded: a newer head of the same pull request
The walk kept its progress every minute and nobody could read it: root-free said only that a search ran.
The account verdict now carries the progress (counts, times, mount points; never a path) as fields and in
its reason, outside what makes a verdict changed. A signed ask from the controller's terminal throws the last
search away and starts a full one, after the operator removed by hand what it found.
2026-10-10 01:55:58 +02:00
jochen a7270f00cb Keep the walk's paths as bytes, forget a walk root superseded, and leave other mounts unread (hq issue 361 review)
mesh/merge-gate pass: builds mesh-host → ace, g14, novox, shanks; no bus step; every machine composes with the change as it did without (4 of 4 compose)
mesh/repo-check pass: its merge-check.sh passed
mesh/delivery delivered
mesh/delivery-group group fix/361-the-setuid-search-runs-to-completion delivered: every member is delivered
The review found a cursor of a name that is not UTF-8 came back changed
from JSON, so a resumed walk skipped what it stood before; an ask to
search again was lost to a restart, which carried the older walk on; a
fresh search judged a filesystem it never walked; a mount point root
cannot read failed or hung the walk; a found file gone before the package
manager was asked failed every resume; and skipped or kept outcomes
started a search on every reconcile, back to back with a long walk.
2026-10-10 01:10:56 +02:00
jochen 2dbbda51c6 Walk for setuid programs in the engine and carry an interrupted walk on (hq issue 361)
mesh/merge-gate pass: builds mesh-host → ace, g14, novox, shanks; no bus step; every machine composes with the change as it did without (4 of 4 compose)
mesh/repo-check pass: its merge-check.sh passed
mesh/delivery-group group fix/361-the-setuid-search-runs-to-completion ready: every member ready, and composed together they pass
mesh/delivery superseded: a newer head of the same pull request
The control-node's walk takes far longer than the engine runs between
updates, so a search that starts over at every restart never completes.
The walk is the engine's own, in lexical order, so its progress is one
cursor per filesystem, kept every minute beside the engine's state and
carried on after a restart while younger than rootsearch.FreshFor. It runs
on a thread of its own at nice 19 and the idle I/O class.
2026-10-10 01:00:47 +02:00
jochen 2410796869 Let the setuid search run to completion and judge from the last complete one (hq issue 361)
A machine with millions of files never finished the walk within fifteen
minutes, so its agent account was never judged and the router refused to
link. Only root can make a setuid-root file, so a complete search stays
sound until root acts: it now runs at idle priority with no bound, is kept
beside the engine's state, judges for rootsearch.FreshFor from its start,
runs again daily and after an apply that moves accounts, packages, actions
or sudo rules, and an incomplete or stale search is never free.
2026-10-10 00:53:05 +02:00
jochen 8fc1d72cd5 Keep the setuid search's time on the caller's clock
mesh/merge-gate pass: builds mesh-host → ace, g14, novox, shanks; no bus step; every machine composes with the change as it did without (4 of 4 compose)
mesh/repo-check pass: its merge-check.sh passed
mesh/delivery failed: its walk failed: a gate on a first machine (what it carried put back), a build, a machine
SetuidCache compared the caller's now with a time read from the wall clock when the search finished. When the caller's clock ran behind the wall clock, a search was never due again: TestTheSetuidSearchRunsInTheBackgroundAndIsKeptForItsInterval, whose clock is a fixed date, has failed on main and every branch since 2026-10-09 18:00 UTC. A search's time is now the now it was started at; a result reads at most one search older than it is, which errs towards searching again.
2026-10-09 20:04:11 +02:00
jochen 2673e7a2c9 Let the setuid search run to its 15-minute bound, ask pacman once, and call a walk with errors incomplete
mesh/merge-gate pass: builds mesh-host → ace, g14, novox, shanks; no bus step; every machine composes with the change as it did without (4 of 4 compose)
mesh/repo-check fail: its merge-check.sh failed: --- FAIL: TestHomesAreAPersonsOrAnAgentsNotAServicesOrRoots (0.00s)
mesh/delivery superseded: a newer head of the same pull request
The search kept a two-minute limit of its own inside its 15-minute bound, so
a long walk always ended incomplete; pacman was asked once per path; and find
exiting with an error but some output was read as a complete walk. The bound
and the not-judged reasons move to the public rootsearch package so the
controller reads the same values (the review of 2026-10-09).
2026-10-09 12:11:57 +02:00
jochen b28d7bbcbf Search for setuid programs in the background, and judge each polkit rule alone
mesh/merge-gate pass: builds mesh-host → ace, g14, novox, shanks; no bus step; every machine composes with the change as it did without (4 of 4 compose)
mesh/repo-check pass: its merge-check.sh passed
mesh/delivery superseded: a newer head of the same pull request
A search over a large disk ran inside the look, holding the judge's lock and
stalling the health statement; it now runs apart, serving its last result,
backing off after a failure, and saying not judged until it has one. And a
rule naming a user, or a comment, no longer hides another rule's
unconditional yes (hq ADR 0266).
2026-10-09 10:10:05 +02:00
jochen d4af8bba1b Judge an opened file's kind and links below a home, and more ways to root
A hard link swapped in for ~/.claude would have had root chown another
account's file; fstat on the descriptor now refuses a second link, a fifo or
an unexpected kind before anything is changed (hq ADR 0266, the re-review).
The judge also finds polkit rules for every account, a runtime's API on TCP,
setgid-to-root programs whoever owns them, setuid programs on every suid
filesystem, and unprotected links; the rest is listed as not judged.
2026-10-09 10:07:52 +02:00
jochen b89b143fe7 Follow no link below a home as root, and judge more ways to root
An account could replace ~/.claude with a link to /etc and have the
node-engine chown, chmod or write through it on the next apply. Below a
person's or an agent's home every component is now opened without
following a link, and a link refuses the resource in words.

The root judge also reads doas and polkit rules, the container runtimes'
sockets with their ACLs, ACLs on the secrets, and setuid-root programs no
package owns, in the C locale; Judged and NotJudged write down exactly
what it covers (hq ADR 0266 review).
2026-10-09 10:07:52 +02:00
jochen 3a727011ad Judge whether an account declared never to become root can, so a machine's agents are known confined
An account an agent runs as (novox/hq ADR 0266) is read on every look for a
uid of 0, a group that grants root, any sudo rule and a mesh secret it can
read; any way found is unhealthy and said, a read that fails is unknown.
2026-10-09 10:07:35 +02:00
jochen ab4ca44f98 Give back only the groups the mesh added, and say when a new login is needed (hq ADR 0252, issue 247)
mesh/merge-gate pass: builds mesh-host → ace, g14, novox, shanks; no bus step; every machine composes with the change as it did without (4 of 4 compose)
mesh/repo-check pass: its merge-check.sh passed
mesh/delivery delivered
mesh/delivery-group group feat/module-groups delivered: every member is delivered
A module puts the operator's account in a group by declaring the account with that group alone.
The node-engine now records each group it added, takes back only those when nothing declared still
asks for them, refuses a group the machine lacks before usermod runs, and states each such account
as its module's resource of kind account: relogin needed while the running session lacks the group.
2026-10-08 12:04:08 +02:00