out-of-range, drop the file reference before returning. (This error
also exists in the RELENG_4 branch.)
o Eliminate the acquisition and release of Giant in readv()
now that malloc() and free() are callable without Giant.
.) don't use MAXPATHLEN + 1, fix logic to compensate.
.) style(9) function parameters.
.) fix line wrapping.
.) remove duplicated error and string handling code.
.) don't NUL terminate already NUL terminated string.
.) all string length variables changed from int to size_t.
.) constify variables.
.) catch when corename would be truncated.
.) cast pid_t and uid_t args for format string.
.) add parens around return arguments.
Help and suggestions from: bde
on committing to these while they were in the Attic after they had been
removed. I think this was because he had the file checked out and already
'modified' while markm cvs rm'ed them, and cvs screws up when trying to
"merge" the modifications with the "rm". And after that the client
state was sufficiently hosed to keep it messed up. Yay CVS! (CVS is
very fragile for adding and removing files remotely)
The existence of these files was pointed out by: ru
be done internally.
Ensure that no one can fsetown() to a dying process/pgrp. We need
to check the process for P_WEXIT to see if it's exiting. Process
groups are already safe because there is no such thing as a pgrp
zombie, therefore the proctree lock completely protects the pgrp
from having sigio structures associated with it after it runs
funsetownlst.
Add sigio lock to witness list under proctree and allproc, but over
proc and pgrp.
Seigo Tanimura helped with this.
Don't try to create a vm object before the file system has a chance to finish
initializing it. This is incorrect for a number of reasons. Firstly, that
VOP requires a lock which the file system may not have initialized yet. Also,
open and others will create a vm object if it is necessary later.
killed by SIGSYS for unimlemented syscalls is bad enough.
Obtained from: Lite2 branch
The Lite2 branch has some other interesting unmerged (?) bits in this
file. They are well hidden among cosmetic regressions.
sys/time.h rev.1.53, etc. Zero out the entire struct clkinfo and not
just the new spare part of it so that there is no possibility of leaking
kernel stack context to userland.
- Reorder fork1() to do malloc() and other blocking operations prior to
acquiring the needed process locks.
- The new process inherit's the credentials of curthread, not the
credentials of the old process.
- Document a really weird race that will come up with KSE allows multiple
kernel threads per process.
exit1() we don't have to release it until we acquire schd_lock to
call cpu_throw().
- Since we can switch at any time due to preemption or a lock release
prior to acquiring sched_lock, don't update switchtime and switchticks
until the very end of exit1() after we have acquired sched_lock.
- Interlock the proctree_lock and proc lock in wait1() and exit1() to
avoid lost wakeups when a parent blocks waiting for a child to exit at
the bottom of wait1(). In exit1() the proc lock interlocked with
proctree_lock (and released after acquiring sched_lock) is that of
the parent process.
- In wait1() use an exclusive lock of proctree lock while we are
looking for a process to harvest. This allows us to completely
remove all references to the process once we've found one (i.e.,
disconnect it from pgrp's, session's, zombproc list, and it's parent's
children list) "atomically" without needing to worry about a lock
upgrade.
- We don't need sched_lock to test if p_stat is SZOMB or SSTOP when holding
the proc lock since the proc lock is always held with p_stat is set to
SZOMB or SSTOP.
- Protect nprocs with an xlock of the allproc_lock.
locks the process.
- Defer other blocking operations such as vrele()'s until after we
release locks.
- execsigs() now requires the proc lock to be held when it is called
rather than locking the process internally.
mallochash. Mallochash is going to go away as soon as I introduce the
kfree/kmalloc api and partially overhaul the malloc wrapper. This can't happen
until all users of the malloc api that expect memory to be aligned on the size
of the allocation are fixed.
Implement the following checks on freed memory in the bucket path:
- Slab membership
- Alignment
- Duplicate free
This previously was only done if we skipped the buckets. This code will slow
down INVARIANTS a bit, but it is smp safe. The checks were moved out of the
normal path and into hooks supplied in uma_dbg.
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.
loading breakage'). The patch fixes serious issues with the VFS
operations vector array which results in a crash when a filesystem module
adding a new VOP is loaded into the kernel. Basically what was happening
before was that the old operations vector was being freed and a new one
allocated. The original MALLOC code tended to reuse the same address
for the case and so the bug did not rear its ugly head until the new memory
subsystem was emplaced.
This patch replaces the temporary workaround Dave O'Brien comitted in 1.58.
The patch is clean enough that I intend to MFC it to stable at some point.
Submitted by: Alexander Kabaev <ak03@gte.com>
MFC after: 1 week
0xdeadc0de and then check for it just before memory is handed off as part
of a new request. This will catch any post free/pre alloc modification of
memory, as well as introduce errors for anything that tries to dereference
it as a pointer.
This code takes the form of special init, fini, ctor and dtor routines that
are specificly used by malloc. It is in a seperate file because additional
debugging aids will want to live here as well.
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.
malloc profiling) also modified the set of pre-defined buckets for the
memory allocator. For reasons unknown to me, this resulted in extensive
memory corruption in the kernel, in particular on SMP boxes, so I'm
committing this work-around until Jeff gets a chance to debug it
properly. David Wolfskill pointed me at this commit as the one that
might be a problem; I've been running this code on two dual-processor
burn-in boxes for about 12 hours now, and the rate of panics due to
memory corruption has dropped to zero (from one every five minutes).
Hopefully not treading on the toes of: jeff
SIGCHLD handler is SIG_IGN. This is a reimplementation of the
problematic revision 1.131 of kern_exit.c. To avoid accessing process
UPAGES, we set a new procsig flag when the SIGCHLD handler is SIG_IGN
and use that instead.
Otherwise we fall back to using the static hints the next time around.
We still have the leftover fallback code there which meant that we skipped
the use_hints checking on the second and subsequent calls. Also, be a bit
more careful about walking off the end of the envp array.
I've extracted this from a larger diff. I hope I didn't miss anything...
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.
by other bits of code, split struct timecounter into two.
struct timecounter contains just the bits which pertains to the hardware
counter and the reading of it.
struct timehands (as in "the hands on a clock") contains all the ugly bit
fidling stuff. Statically compile ten timehands.
This commit is the functional part. A later cosmetic patch will rename
various variables and fieldnames.
timeout loop.
Limit the rate at which we wind the timecounters to approx 1000 Hz.
This limits the precision of the get{bin,nano,micro}[up]time(9)
functions to roughly a millisecond.
timecounter will be used starting at the next second, which is
good enough for sysctl purposes. If better adjustment is needed
the NTP PLL should be used.
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
- malformed environment strings (ones without an '=') were not rejected.
There shouldn't be any of these, but when the static environment is
empty it always begins with one of these; this one should be considered
as the terminator after the end of the environment, but it isn't.
- the comparison of the name being looked up with the name in the
environment was fuzzy -- only the characters up to the length of the
latter were compared, so _getenv_static("foobar") matched "foo=..."
in the environment and everything matched "" in the empty environment.
MFC after: 3 days
#!bin/sh
# Original version of this by Michael Reifenberger
# <root@nihil.plaut.de>.
mdconfig -d -u 11 >/dev/null 2>&1
dd if=/dev/zero of=zz bs=1m count=1
while :
do
mdconfig -a -t vnode -f zz -u 11
fdisk -f - -iv /dev/md11 <<EOF1
g c1 h64 s32
p 1 165 0 2048
a 1
EOF1
mdconfig -d -u 11
done
Garbage pointers in __si_u were not cleared by destroy_dev(). Not
clearing si_disk made the above fatal because the disk layer uses
si_disk as a flag to indicate that the dev_t has been completely
initialized. disk_destroy() clears si_disk for the parent dev_t
but doesn't get called for children.
Not fixed:
- setting the undocumented sysctl debug.free_devt should cause more
complete destruction of the dev_t including clearing of __si_u, but
actually causes the above to panic a little earlier.
- the loop leaks 10 memory allocations per iteration (4 DEVFS, 2 devbuf
and 4 dev_t).
Reviewed by: timeout by MAINTAINER after 3 months
the symbol index defined by the relocation. The elf_lookup() support
function is to be used by elf_reloc() when symbol lookups need to be
done. The elf_lookup() function operates on the symbol index and
will do a symbol name based lookup when such is required, otherwise
it uses the symbol index directly. This solves the problem seen on
ia64 where the symbol hash table does not contain local symbols and
a symbol name based lookup would fail for those symbols.
Don't pass the symbol name to elf_reloc(), as it isn't used any more.
civilized way which doesn't cause grief.
The problem is that it is not generally safe to cast a "struct bio
*" to a "struct buf *". Things like ccd, vinum, ata-raid and GEOM
constructs bio's which are not entrails of a struct buf.
Also, curthread may or may not have anything to do with the I/O request
at hand.
The correct solution can either be to tag struct bio's with a
priority derived from the requesting threads nice and have disksort
act on this field, this wouldn't address the "silly-seek syndrome"
where two equal processes bang the diskheads from one edge to the
other of the disk repeatedly.
Alternatively, and probably better: a sleep should be introduced
either at the time the I/O is requested or at the time it is completed
where we can be sure to sleep in the right thread.
The sleep also needs to be in constant timeunits, 1/hz can be practicaly
any sub-second size, at high HZ the current code practically doesn't
do anything.
the DT_PLTGOT value. On ia64 this is the value of GP. We need this
to construct function descriptors, but the elf file structure is
not exported to MD code.
Note that the name of the function is based on the meaning that
DT_PLTGOT has on ia64. This may differ on other architectures. As
such, link_elf_get_gp() has a high level of MD to it. Renaming the
function to describe what DT_* value is returned makes it generic,
but also makes the MD code less clear and if we only need this on
ia64, then a general name for a specific function doesn't help.
In short: I don't know what is "right" at this time, so I'll go
with what I have.
in various extattr_*() calls to match the rest of the file. Originally,
these bits at the end looked more like style(9). This patch was submitted
by green by way of the TrustedBSD MAC tree, and I fixed a few problems
with it on the way through. Someone with more time on their hands should
convert the entire file to style(9); this commit is for diff reduction
purposes.
Submitted by: green
Obtained from: TrustedBSD Project
Sponsored by: DARPA, NAI Labs
constructing a struct aio and invoking VOP_READ() directly. This cleans
up the code a little, but also has the advantage of making sure almost
all vnode read/write access in the kernel goes through the helper
function, meaning that instrumentation of that helper function can impact
almost all relevant read/write operations. In this case, it permits us
to put MAC hooks into vn_rdwr() and not modify uipc_syscalls.c (yet).
In general, if helper vn_*() functions exist, they should be used in
preference to direct VOP's in system call service code.
Submitted by: green
Obtained from: TrustedBSD Project
Sponsored by: DARPA, NAI Labs
needed in the current code, in the MAC tree, create_init() relies on the
ability to modify the credentials present for initproc, and should not
perform that modification on a shared credential. Pro-active diff
reduction against MAC changes that are in the queue; also facilitates
other work, including the capabilities implementation.
Submitted by: green
Obtained from: TrustedBSD Project
Sponsored by: DARPA, NAI Labs
