Turn the sigio sx into a mutex.
Sigio lock is really only needed to protect interrupts from dereferencing
the sigio pointer in an object when the sigio itself is being destroyed.
In order to do this in the most unintrusive manner change pgsigio's
sigio * argument into a **, that way we can lock internally to the
function.
Requested by: bde
Since locking sigio_lock is usually followed by calling pgsigio(),
move the declaration of sigio_lock and the definitions of SIGIO_*() to
sys/signalvar.h.
While I am here, sort include files alphabetically, where possible.
of a socket. This avoids lock order reversal caused by locking a
process in pgsigio().
sowakeup() and the callers of it (sowwakeup, soisconnected, etc.) now
require sigio_lock to be locked. Provide sowwakeup_locked(),
soisconnected_locked(), and so on in case where we have to modify a
socket and wake up a process atomically.
LRU fashion when the listen queue fills up. Previously, there was
no mechanism to kick out old sockets, leading to an easy DoS of
daemons using accept filtering.
Reviewed by: alfred
MFC after: 3 days
Remove the explicit call to aio_proc_rundown() from exit1(), instead AIO
will use at_exit(9).
Add functions at_exec(9), rm_at_exec(9) which function nearly the
same as at_exec(9) and rm_at_exec(9), these functions are called
on behalf of modules at the time of execve(2) after the image
activator has run.
Use a modified version of tegge's suggestion via at_exec(9) to close
an exploitable race in AIO.
Fix SYSCALL_MODULE_HELPER such that it's archetecuterally neutral,
the problem was that one had to pass it a paramater indicating the
number of arguments which were actually the number of "int". Fix
it by using an inline version of the AS macro against the syscall
arguments. (AS should be available globally but we'll get to that
later.)
Add a primative system for dynamically adding kqueue ops, it's really
not as sophisticated as it should be, but I'll discuss with jlemon when
he's around.
code only passed up the connection to the tcp stack when it was complete,
so it went directly into the so_comp (complete) queue. However, with
accept filters, there is an additional phase before calling it "complete".
Reviewed by: jlemon
always deriving the credential for a newly accepted connection from
the listen socket. Previously, the selection of the credential
depended on the protocol: UNIX domain sockets would use the
connecting process's credential, and protocols supporting a creation
of the socket before the receiving end called accept() would use
the listening socket. After this change, it is always the listening
credential.
Reviewed by: green
vnodes. This will hopefully serve as a base from which we can
expand the MP code. We currently do not attempt to obtain any
mutex or SX locks, but the door is open to add them when we nail
down exactly how that part of it is going to work.
- crhold() returns a reference to the ucred whose refcount it bumps.
- crcopy() now simply copies the credentials from one credential to
another and has no return value.
- a new crshared() primitive is added which returns true if a ucred's
refcount is > 1 and false (0) otherwise.
Note ALL MODULES MUST BE RECOMPILED
make the kernel aware that there are smaller units of scheduling than the
process. (but only allow one thread per process at this time).
This is functionally equivalent to teh previousl -current except
that there is a thread associated with each process.
Sorry john! (your next MFC will be a doosie!)
Reviewed by: peter@freebsd.org, dillon@freebsd.org
X-MFC after: ha ha ha ha
around, use a common function for looking up and extracting the tunables
from the kernel environment. This saves duplicating the same function
over and over again. This way typically has an overhead of 8 bytes + the
path string, versus about 26 bytes + the path string.
other "system" header files.
Also help the deprecation of lockmgr.h by making it a sub-include of
sys/lock.h and removing sys/lockmgr.h form kernel .c files.
Sort sys/*.h includes where possible in affected files.
OK'ed by: bde (with reservations)
could not compress into clusters. This could result in lots of
wasted clusters while recieving small packets from an interface
that uses clusters for all it's packets.
Patch is partially from BSDi (limiting the size of the copy) and
based on a patch for 4.1 by Ian Dowse <iedowse@maths.tcd.ie> and
myself.
Reviewed by: bmilekic
Obtained From: BSDi
Submitted by: iedowse
chgsbsize(), which are called rather frequently and may be called from an
interrupt context in the case of chgsbsize(). Instead, do the hash table
lookup and maintenance when credentials are changed, which is a lot less
frequent. Add pointers to the uidinfo structures to the ucred and pcred
structures for fast access. Pass a pointer to the credential to chgproccnt()
and chgsbsize() instead of passing the uid. Add a reference count to the
uidinfo structure and use it to decide when to free the structure rather
than freeing the structure when the resource consumption drops to zero.
Move the resource tracking code from kern_proc.c to kern_resource.c. Move
some duplicate code sequences in kern_prot.c to separate helper functions.
Change KASSERTs in this code to unconditional tests and calls to panic().
the chgsbsize() call to use a "subject" pointer (&sb.sb_hiwat) and
a u_long target to set it to. The whole thing is splnet().
This fixes a problem that jdp has been able to provoke.
1) while allocating a uidinfo struct malloc is called with M_WAITOK,
it's possible that while asleep another process by the same user
could have woken up earlier and inserted an entry into the uid
hash table. Having redundant entries causes inconsistancies that
we can't handle.
fix: do a non-waiting malloc, and if that fails then do a blocking
malloc, after waking up check that no one else has inserted an entry
for us already.
2) Because many checks for sbsize were done as "test then set" in a non
atomic manner it was possible to exceed the limits put up via races.
fix: instead of querying the count then setting, we just attempt to
set the count and leave it up to the function to return success or
failure.
3) The uidinfo code was inlining and repeating, lookups and insertions
and deletions needed to be in their own functions for clarity.
Reviewed by: green
accept filters are now loadable as well as able to be compiled into
the kernel.
two accept filters are provided, one that returns sockets when data
arrives the other when an http request is completed (doesn't work
with 0.9 requests)
Reviewed by: jmg
until the incoming connection has either data waiting or what looks like a
HTTP request header already in the socketbuffer. This ought to reduce
the context switch time and overhead for processing requests.
The initial idea and code for HTTPACCEPT came from Yahoo engineers and has
been cleaned up and a more lightweight DELAYACCEPT for non-http servers
has been added
Reviewed by: silence on hackers.
Now this check is necessary because IPv6 source routing might use
control data bigger than MLEN. (e.g. 16bytes IPv6 addr x 23 hops)
Actually mbuf cluster should be used in uipc_socket.c:sbcreatecontrol()
and uipc_syscalls.c:sockargs() when data size is bigger then MLEN,
and such patches were already in KAME environment and have been
confirmed to work well. I just forgot to merge them into 4.0, sorry.
For safety, I'll postpone such patches until after 4.0 release.
The effect of postponement is followings.
-Ping6 source routing hops are limitted to around 6 or so.
-If some apps do setsockopt IPV6_RTHDR and try to receive
incoming IPv6 source routing info, it can't receive more
than 6 hops source routing info.
(But currently, no apps seems to be doing it.)
Approved by: jkh
Make gratuitous style(9) fixes (me, not the submitter) to make the aio
code more readable.
PR: kern/12053
Submitted by: Chris Sedore <cmsedore@maxwell.syr.edu>
an empty mbuf to stay in the queue, then causing a needless panic
because sb_cc == 0 and sb_mbcnt != 0.
But we still need to panic rather than endlessly looping if, for
some reason, sb_cc == 0 and there are non-empty mbufs in the queue.
PR: kern/11988
Reviewed by: fenner
Make a sonewconn3() which takes an extra argument (proc) so new sockets created
with sonewconn() from a user's system call get the correct credentials, not
just the parent's credentials.
into uipc_mbuf.c. This reduces three sets of identical tunable code to
one set, and puts the initialisation with the mbuf code proper.
Make NMBUFs tunable as well.
Move the nmbclusters sysctl here as well.
Move the initialisation of maxsockets from param.c to uipc_socket2.c,
next to its corresponding sysctl.
Use the new tunable macros for the kern.vm.kmem.size tunable (this should have
been in a separate commit, whoops).
This is the change to struct sockets that gets rid of so_uid and replaces
it with a much more useful struct pcred *so_cred. This is here to be able
to do socket-level credential checks (i.e. IPFW uid/gid support, to be added
to HEAD soon). Along with this comes an update to pidentd which greatly
simplifies the code necessary to get a uid from a socket. Soon to come:
a sysctl() interface to finding individual sockets' credentials.
where select(2) can return that a listening socket has a connected socket
queued, the connection is broken, and the user calls accept(2), which then
blocks because there are no connections queued.
Reviewed by: wollman
Obtained from: NetBSD
(ftp://ftp.NetBSD.ORG/pub/NetBSD/misc/security/patches/19990120-accept)
from an interrupt context and fsetown() wants to peek at curproc, call
malloc(..., M_WAITOK), and fiddle with various unprotected data structures.
The fix is to move the code that duplicates the F_SETOWN/FIOSETOWN state
of the original socket to the new socket from sonewconn() to accept1(),
since accept1() runs in the correct context. Deferring this until the
process calls accept() is harmless since the process can't do anything
useful with SIGIO on the new socket until it has the descriptor for that
socket.
One could make the case for not bothering to duplicate the
F_SETOWN/FIOSETOWN state and requiring the process to explicitly make the
fcntl() or ioctl() call on the new socket, but this would be incompatible
with the previous implementation and might break programs which rely on
the old semantics.
This bug was discovered by Andrew Gallatin <gallatin@cs.duke.edu>.
