of the adjusted sb_max into a sysctl handler for sb_max and assigning it to
a variable that is used instead. This eliminates the 32bit multiply and
divide from the fast path that was being done previously.
expensive (!) 64bit multiply, divide, and comparison aren't necessary
(this came in originally from rev 1.19 to fix an overflow with large
sb_max or MCLBYTES).
The 64bit math in this function was measured in some kernel profiles as
being as much as 5-8% of the total overhead of the TCP/IP stack and
is eliminated with this commit. There is a harmless rounding error (of
about .4% with the standard values) introduced with this change,
however this is in the conservative direction (downward toward a
slightly smaller maximum socket buffer size).
MFC after: 3 days
kernel access control.
Invoke the necessary MAC entry points to maintain labels on sockets.
In particular, invoke entry points during socket allocation and
destruction, as well as creation by a process or during an
accept-scenario (sonewconn). For UNIX domain sockets, also assign
a peer label. As the socket code isn't locked down yet, locking
interactions are not yet clear. Various protocol stack socket
operations (such as peer label assignment for IPv4) will follow.
Obtained from: TrustedBSD Project
Sponsored by: DARPA, NAI Labs
not responding) then drop any data on the outgoing queue in
soisdisconnected because there is no way to get it to its destination
any longer.
The only objection to this patch I got on -net was from Terry, who
wasn't sure that the condition in question could arise, so I provided
some example code.
initialized socket with no qlimit was being passed in. In order
to handle this case properly, we must not use >= when comparing
queue sizes to qlimit. As a result of this improper handling,
a panic could result in certain cases.
PR: 38325
MFC after: 3 days
o Add a mutex (sb_mtx) to struct sockbuf. This protects the data in a
socket buffer. The mutex in the receive buffer also protects the data
in struct socket.
o Determine the lock strategy for each members in struct socket.
o Lock down the following members:
- so_count
- so_options
- so_linger
- so_state
o Remove *_locked() socket APIs. Make the following socket APIs
touching the members above now require a locked socket:
- sodisconnect()
- soisconnected()
- soisconnecting()
- soisdisconnected()
- soisdisconnecting()
- sofree()
- soref()
- sorele()
- sorwakeup()
- sotryfree()
- sowakeup()
- sowwakeup()
Reviewed by: alfred
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.
