Commit Graph

82 Commits

Author SHA1 Message Date
Robert Watson
d3778141bf Audit path passed to the acct() system call.
Obtained from:	TrustedBSD Project
2006-06-05 13:02:34 +00:00
John Baldwin
11178ee4c1 Conditionalize locking of Giant for VFS in acct(2). We already
conditionally acquired Giant in the other parts of the accounting code.
2006-03-28 21:26:59 +00:00
John Baldwin
222fdf4bff Provide some anti-footshooting. Don't allow the user to set the interval
for acctwatch() runs to be negative or zero as this could result in either
a possible hang (or panic if INVARIANTS is on).  Previously the accounting
code handled the <= 0 case by calling acctwatch on every clock tick (eww!)
due to an implementation detail of callout_reset().  (Tick counts of
<= 0 are converted to 1).

MFC after:	3 days
2006-02-07 18:59:47 +00:00
John Baldwin
505a14934e - Add a kthread to periodically call acctwatch() when accounting is active
instead of calling acctwatch() from softclock.  The acctwatch() function
  needs to hold an sx lock and also makes a VFS call, and neither of these
  are good things (or safe) to do from a callout.  The kthread only exists
  and is running when accounting is turned on; it is started and stopped
  as needed.  I didn't run acctwatch() via the thread taskqueue at Robert's
  request as he was worried that if the accounting file was over NFS the
  VFS_STAT() calls might stall other work on the taskqueue.
- Add an acct_disable() function to take care of closing the accounting
  vnode and cleaning up so we don't duplicate the same code in two
  different places.

MFC after:	3 days
2006-02-07 16:04:03 +00:00
John Baldwin
b0864d13ab Sort includes. 2006-02-03 16:37:55 +00:00
John Baldwin
f6b457923d Whitespace fix.
Submitted by:	Wojciech A. Koszek <dunstan at zsno ids czest pl>
2006-02-02 20:14:52 +00:00
Robert Watson
71909edec8 Significant refactoring of the accounting code to improve locking and VFS
happiness, as well as correct other bugs:

- Replace notion of current and saved accounting credential/vnode with a
  single credential/vnode and an acct_suspended flag.  This simplifies the
  accounting logic substantially.

- Replace acct_mtx with acct_sx, a sleepable lock held exclusively during
  reconfiguration and space polling, but shared during log entry
  generation.  This avoids holding a mutex over sleepable VFS operations.

- Hold the sx lock over the duration of the I/O so that the vnode I/O
  cannot occur after vnode close, which could occur previously if
  accounting was disabled as a process exited.

- Write the accounting log entry with Giant conditionally acquired based
  on the file system where the log is stored.  Previously, the accounting
  code relied on the caller acquiring Giant.

- Acquire Giant conditionally in the accounting callout based on the file
  system where the accounting log is stored.  Run the callout MPSAFE.

- Expose acct_suspended via a read-only sysctl so it is possibly to
  programmatically determine whether accounting is suspended or not without
  attempting to parse logs.

- Check both acct_vp and acct_suspended lock-free before entering the
  accounting sx lock in acct().

- When accounting is disabled due to a VBAD vnode (i.e., forceable unmount),
  generate a log message indicating accounting has been disabled.

- Correct a long-standing bug in how free space is calculated and compared
  to the required space: generate and compare signed results, not unsigned
  results, or negative free space will cause accounting to not be suspended
  when required, or worse, incorrectly resumed once negative free space is
  reached.

MFC after:	2 weeks
2005-11-12 10:45:13 +00:00
Robert Watson
87328e07e0 Pass 'curthread' into VFS_STATFS() from acctwatch(), rather than passing
NULL.  The NFS client expects that a thread will always be present for a
VOP so that it can check for signal conditions, and will dereference a
NULL pointer if one isn't present.

MFC after:	3 days
2005-09-21 15:28:07 +00:00
Robert Watson
081322613b When mac_check_system_acct() fails, make sure to unlock as well as close
the vnode.

Pointed out by:	jeff
2005-03-01 08:56:13 +00:00
Robert Watson
2b05b557ff In acct_process(), do a lockless read of acctvp to see if it's NULL
before deciding to do more expensive locking to account for process
exit.  This acceptable minor race avoids two mutex operations in
that highly common case of accounting not being enabled.

MFC after:	2 weeks
2005-01-08 04:45:57 +00:00
John Baldwin
78c85e8dfc Rework how we store process times in the kernel such that we always store
the raw values including for child process statistics and only compute the
system and user timevals on demand.

- Fix the various kern_wait() syscall wrappers to only pass in a rusage
  pointer if they are going to use the result.
- Add a kern_getrusage() function for the ABI syscalls to use so that they
  don't have to play stackgap games to call getrusage().
- Fix the svr4_sys_times() syscall to just call calcru() to calculate the
  times it needs rather than calling getrusage() twice with associated
  stackgap, etc.
- Add a new rusage_ext structure to store raw time stats such as tick counts
  for user, system, and interrupt time as well as a bintime of the total
  runtime.  A new p_rux field in struct proc replaces the same inline fields
  from struct proc (i.e. p_[isu]ticks, p_[isu]u, and p_runtime).  A new p_crux
  field in struct proc contains the "raw" child time usage statistics.
  ruadd() has been changed to handle adding the associated rusage_ext
  structures as well as the values in rusage.  Effectively, the values in
  rusage_ext replace the ru_utime and ru_stime values in struct rusage.  These
  two fields in struct rusage are no longer used in the kernel.
- calcru() has been split into a static worker function calcru1() that
  calculates appropriate timevals for user and system time as well as updating
  the rux_[isu]u fields of a passed in rusage_ext structure.  calcru() uses a
  copy of the process' p_rux structure to compute the timevals after updating
  the runtime appropriately if any of the threads in that process are
  currently executing.  It also now only locks sched_lock internally while
  doing the rux_runtime fixup.  calcru() now only requires the caller to
  hold the proc lock and calcru1() only requires the proc lock internally.
  calcru() also no longer allows callers to ask for an interrupt timeval
  since none of them actually did.
- calcru() now correctly handles threads executing on other CPUs.
- A new calccru() function computes the child system and user timevals by
  calling calcru1() on p_crux.  Note that this means that any code that wants
  child times must now call this function rather than reading from p_cru
  directly.  This function also requires the proc lock.
- This finishes the locking for rusage and friends so some of the Giant locks
  in exit1() and kern_wait() are now gone.
- The locking in ttyinfo() has been tweaked so that a shared lock of the
  proctree lock is used to protect the process group rather than the process
  group lock.  By holding this lock until the end of the function we now
  ensure that the process/thread that we pick to dump info about will no
  longer vanish while we are trying to output its info to the console.

Submitted by:	bde (mostly)
MFC after:	1 month
2004-10-05 18:51:11 +00:00
Poul-Henning Kamp
f3732fd15b Second half of the dev_t cleanup.
The big lines are:
	NODEV -> NULL
	NOUDEV -> NODEV
	udev_t -> dev_t
	udev2dev() -> findcdev()

Various minor adjustments including handling of userland access to kernel
space struct cdev etc.
2004-06-17 17:16:53 +00:00
Bruce Evans
01e3f3ae4f Fixed some style bugs (mainly misplaced comments, and totally disordered
declarations in acct_process()).
2004-03-04 09:47:09 +00:00
John Baldwin
91d5354a2c Locking for the per-process resource limits structure.
- struct plimit includes a mutex to protect a reference count.  The plimit
  structure is treated similarly to struct ucred in that is is always copy
  on write, so having a reference to a structure is sufficient to read from
  it without needing a further lock.
- The proc lock protects the p_limit pointer and must be held while reading
  limits from a process to keep the limit structure from changing out from
  under you while reading from it.
- Various global limits that are ints are not protected by a lock since
  int writes are atomic on all the archs we support and thus a lock
  wouldn't buy us anything.
- All accesses to individual resource limits from a process are abstracted
  behind a simple lim_rlimit(), lim_max(), and lim_cur() API that return
  either an rlimit, or the current or max individual limit of the specified
  resource from a process.
- dosetrlimit() was renamed to kern_setrlimit() to match existing style of
  other similar syscall helper functions.
- The alpha OSF/1 compat layer no longer calls getrlimit() and setrlimit()
  (it didn't used the stackgap when it should have) but uses lim_rlimit()
  and kern_setrlimit() instead.
- The svr4 compat no longer uses the stackgap for resource limits calls,
  but uses lim_rlimit() and kern_setrlimit() instead.
- The ibcs2 compat no longer uses the stackgap for resource limits.  It
  also no longer uses the stackgap for accessing sysctl's for the
  ibcs2_sysconf() syscall but uses kernel_sysctl() instead.  As a result,
  ibcs2_sysconf() no longer needs Giant.
- The p_rlimit macro no longer exists.

Submitted by:	mtm (mostly, I only did a few cleanups and catchups)
Tested on:	i386
Compiled on:	alpha, amd64
2004-02-04 21:52:57 +00:00
Poul-Henning Kamp
7c89f162bc Add fdidx argument to vn_open() and vn_open_cred() and pass -1 throughout. 2003-07-27 17:04:56 +00:00
Bosko Milekic
48719ca7c8 Change the style of the english used to print accounting enabled
and disabled.  This means no period at the end and changing
"Process accounting <foo>" to "Accounting <foo>".

Pointed out by: bde
2003-07-16 13:20:10 +00:00
Bosko Milekic
d2dbf5bc0b Log process accounting activation/deactivation.
Useful for some auditing purposes.

Submitted by: Christian S.J. Peron <maneo@bsdpro.com>
PR: kern/54529
2003-07-16 03:59:50 +00:00
David E. O'Brien
677b542ea2 Use __FBSDID(). 2003-06-11 00:56:59 +00:00
Dag-Erling Smørgrav
87ccef7b77 Instead of recording the Unix time in a process when it starts, record the
uptime.  Where necessary, convert it back to Unix time by adding boottime
to it.  This fixes a potential problem in the accounting code, which would
compute the elapsed time incorrectly if the Unix time was stepped during
the lifetime of the process.
2003-05-01 16:59:23 +00:00
John Baldwin
7e653dbd3b Hold the proc lock across a wider range of fields that it protects. 2003-04-17 22:20:30 +00:00
John Baldwin
2d055ab20f Trim some trailing whitespace. 2003-03-13 23:07:09 +00:00
Tim J. Robbins
27e39ae4d8 Remove the PL_SHAREMOD flag from struct plimit, which could have been
used to share resource limits between rfork threads, but never was.
Removing it makes resource limit locking much simpler -- only the current
process can change the contents of the structure that p_limit points to.
2003-02-20 04:18:42 +00:00
Alfred Perlstein
f97182acf8 unwrap lines made short enough by SCARGS removal 2002-12-14 08:18:06 +00:00
Alfred Perlstein
b80521fee5 remove syscallarg().
Suggested by: peter
2002-12-14 02:07:32 +00:00
Alfred Perlstein
d1e405c5ce SCARGS removal take II. 2002-12-14 01:56:26 +00:00
Alfred Perlstein
bc9e75d7ca Backout removal SCARGS, the code freeze is only "selectively" over. 2002-12-13 22:41:47 +00:00
Alfred Perlstein
0bbe7292e1 Remove SCARGS.
Reviewed by: md5
2002-12-13 22:27:25 +00:00
Bill Fenner
8b5f8b061a Don't hold acct_mtx over limcopy(), since it's unnecessary and
limcopy() can sleep.

Approved by:	re
2002-11-26 18:04:12 +00:00
Giorgos Keramidas
5f9ae8e026 Typo in comment: commmand -> command
Reviewed by:	jhb
2002-11-05 14:54:07 +00:00
Robert Watson
e5e820fd1f Permit MAC policies to instrument the access control decisions for
system accounting configuration and for nfsd server thread attach.
Policies might use this to protect the integrity or confidentiality
of accounting data, limit the ability to turn on or off accounting,
as well as to prevent inappropriately labeled threads from becoming nfs
server threads.

Obtained from:	TrustedBSD Project
Sponsored by:	DARPA, Network Associates Laboratories
2002-11-04 15:13:36 +00:00
Robert Watson
b497ca81d6 Make sure that the accounting credential is saved along with the vp
when accounting is suspended--otherwise when accounting is restored,
we may incorrectly assume the credential is valid.

Panics experienced by:	juli
2002-10-05 20:05:23 +00:00
Robert Watson
289c6dea76 Don't call VOP_LEASE() while holding the accounting mutex. 2002-09-18 01:56:13 +00:00
Andrew R. Reiter
b4dcc46af5 - Fix two obvious locking bugs; 1) returning with lock held when it needed
to be dropped, 2) attempting to lock acct_mtx while already holding it.
  Sorry to those who experienced pain.
- Added two comments referring to two areas in which acct_mtx is held over
  vnode operations that might sleep.  Patch in the works for this.
2002-09-12 05:00:32 +00:00
Andrew R. Reiter
4f39d5d511 - Lock down the accounting code globals with a subsystem mutex.
Reviewed by:	jhb, mdodd
2002-09-11 04:10:41 +00:00
Robert Watson
9ca435893b In order to better support flexible and extensible access control,
make a series of modifications to the credential arguments relating
to file read and write operations to cliarfy which credential is
used for what:

- Change fo_read() and fo_write() to accept "active_cred" instead of
  "cred", and change the semantics of consumers of fo_read() and
  fo_write() to pass the active credential of the thread requesting
  an operation rather than the cached file cred.  The cached file
  cred is still available in fo_read() and fo_write() consumers
  via fp->f_cred.  These changes largely in sys_generic.c.

For each implementation of fo_read() and fo_write(), update cred
usage to reflect this change and maintain current semantics:

- badfo_readwrite() unchanged
- kqueue_read/write() unchanged
  pipe_read/write() now authorize MAC using active_cred rather
  than td->td_ucred
- soo_read/write() unchanged
- vn_read/write() now authorize MAC using active_cred but
  VOP_READ/WRITE() with fp->f_cred

Modify vn_rdwr() to accept two credential arguments instead of a
single credential: active_cred and file_cred.  Use active_cred
for MAC authorization, and select a credential for use in
VOP_READ/WRITE() based on whether file_cred is NULL or not.  If
file_cred is provided, authorize the VOP using that cred,
otherwise the active credential, matching current semantics.

Modify current vn_rdwr() consumers to pass a file_cred if used
in the context of a struct file, and to always pass active_cred.
When vn_rdwr() is used without a file_cred, pass NOCRED.

These changes should maintain current semantics for read/write,
but avoid a redundant passing of fp->f_cred, as well as making
it more clear what the origin of each credential is in file
descriptor read/write operations.

Follow-up commits will make similar changes to other file descriptor
operations, and modify the MAC framework to pass both credentials
to MAC policy modules so they can implement either semantic for
revocation.

Obtained from:	TrustedBSD Project
Sponsored by:	DARPA, NAI Labs
2002-08-15 20:55:08 +00:00
Robert Watson
2d70161756 Cache the credential provided during accton() for use in later accounting
vnode operations.  This permits the rights of the user (typically root)
used to turn on accounting to be used when writing out accounting entries,
rather than the credentials of the process generating the accounting
record.  This fixes accounting in a number of environments, including
file systems that offer revocation support, MAC environments, some
securelevel scenarios, and in some NFS environments.

Obtained from:	TrustedBSD Project
Sponsored by:	DARPA, NAI Labs
2002-08-07 19:30:16 +00:00
Johan Karlsson
5b60674451 Save flags returned by vn_open and use them when calling vn_close.
Reviewed by:    bde
Approved by:    sheldonh (mentor)
2002-07-21 15:22:56 +00:00
Johan Karlsson
92da2e7671 Open accounting file for appending, not general writing.
This allows accton(1) to be used with an append-only file.

PR:		7169
Reported by:	Joao Carlos Mendes Luis <jonny@jonny.eng.br>
Reviewed by:	bde
Approved by:	sheldonh (mentor)
MFC after:	2 weeks
2002-07-10 17:31:58 +00:00
Tom Rhodes
d394511de3 More s/file system/filesystem/g 2002-05-16 21:28:32 +00:00
John Baldwin
16e7bc7b90 - Remove an early KSE diagnostic panic. The thread pointer here is always
curthread.
- We don't need Giant to do suser() checks now, so don't lock Giant until
  after the check.
2002-04-09 19:58:38 +00:00
John Baldwin
44731cab3b Change the suser() API to take advantage of td_ucred as well as do a
general cleanup of the API.  The entire API now consists of two functions
similar to the pre-KSE API.  The suser() function takes a thread pointer
as its only argument.  The td_ucred member of this thread must be valid
so the only valid thread pointers are curthread and a few kernel threads
such as thread0.  The suser_cred() function takes a pointer to a struct
ucred as its first argument and an integer flag as its second argument.
The flag is currently only used for the PRISON_ROOT flag.

Discussed on:	smp@
2002-04-01 21:31:13 +00:00
Alfred Perlstein
4d77a549fe Remove __P. 2002-03-19 21:25:46 +00:00
John Baldwin
a854ed9893 Simple p_ucred -> td_ucred changes to start using the per-thread ucred
reference.
2002-02-27 18:32:23 +00:00
Seigo Tanimura
f591779bb5 Lock struct pgrp, session and sigio.
New locks are:

- pgrpsess_lock which locks the whole pgrps and sessions,
- pg_mtx which protects the pgrp members, and
- s_mtx which protects the session members.

Please refer to sys/proc.h for the coverage of these locks.

Changes on the pgrp/session interface:

- pgfind() needs the pgrpsess_lock held.

- The caller of enterpgrp() is responsible to allocate a new pgrp and
  session.

- Call enterthispgrp() in order to enter an existing pgrp.

- pgsignal() requires a pgrp lock held.

Reviewed by:	jhb, alfred
Tested on:	cvsup.jp.FreeBSD.org
		(which is a quad-CPU machine running -current)
2002-02-23 11:12:57 +00:00
Robert Watson
fc5d29ef7d o Move suser() calls in kern/ to using suser_xxx() with an explicit
credential selection, rather than reference via a thread or process
  pointer.  This is part of a gradual migration to suser() accepting
  a struct ucred instead of a struct proc, simplifying the reference
  and locking semantics of suser().

Obtained from:	TrustedBSD Project
2001-11-01 20:56:57 +00:00
Julian Elischer
b40ce4165d KSE Milestone 2
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
2001-09-12 08:38:13 +00:00
Matthew Dillon
116734c4d1 Pushdown Giant for acct(), kqueue(), kevent(), execve(), fork(),
vfork(), rfork(), jail().
2001-09-01 03:04:31 +00:00
Robert Watson
3c4543e046 o Reduce gratuitous whitespace difference from Darwin. 2001-08-29 17:18:04 +00:00
Robert Watson
b1fc0ec1a7 o Merge contents of struct pcred into struct ucred. Specifically, add the
real uid, saved uid, real gid, and saved gid to ucred, as well as the
  pcred->pc_uidinfo, which was associated with the real uid, only rename
  it to cr_ruidinfo so as not to conflict with cr_uidinfo, which
  corresponds to the effective uid.
o Remove p_cred from struct proc; add p_ucred to struct proc, replacing
  original macro that pointed.
  p->p_ucred to p->p_cred->pc_ucred.
o Universally update code so that it makes use of ucred instead of pcred,
  p->p_ucred instead of p->p_pcred, cr_ruidinfo instead of p_uidinfo,
  cr_{r,sv}{u,g}id instead of p_*, etc.
o Remove pcred0 and its initialization from init_main.c; initialize
  cr_ruidinfo there.
o Restruction many credential modification chunks to always crdup while
  we figure out locking and optimizations; generally speaking, this
  means moving to a structure like this:
        newcred = crdup(oldcred);
        ...
        p->p_ucred = newcred;
        crfree(oldcred);
  It's not race-free, but better than nothing.  There are also races
  in sys_process.c, all inter-process authorization, fork, exec, and
  exit.
o Remove sigio->sio_ruid since sigio->sio_ucred now contains the ruid;
  remove comments indicating that the old arrangement was a problem.
o Restructure exec1() a little to use newcred/oldcred arrangement, and
  use improved uid management primitives.
o Clean up exit1() so as to do less work in credential cleanup due to
  pcred removal.
o Clean up fork1() so as to do less work in credential cleanup and
  allocation.
o Clean up ktrcanset() to take into account changes, and move to using
  suser_xxx() instead of performing a direct uid==0 comparision.
o Improve commenting in various kern_prot.c credential modification
  calls to better document current behavior.  In a couple of places,
  current behavior is a little questionable and we need to check
  POSIX.1 to make sure it's "right".  More commenting work still
  remains to be done.
o Update credential management calls, such as crfree(), to take into
  account new ruidinfo reference.
o Modify or add the following uid and gid helper routines:
      change_euid()
      change_egid()
      change_ruid()
      change_rgid()
      change_svuid()
      change_svgid()
  In each case, the call now acts on a credential not a process, and as
  such no longer requires more complicated process locking/etc.  They
  now assume the caller will do any necessary allocation of an
  exclusive credential reference.  Each is commented to document its
  reference requirements.
o CANSIGIO() is simplified to require only credentials, not processes
  and pcreds.
o Remove lots of (p_pcred==NULL) checks.
o Add an XXX to authorization code in nfs_lock.c, since it's
  questionable, and needs to be considered carefully.
o Simplify posix4 authorization code to require only credentials, not
  processes and pcreds.  Note that this authorization, as well as
  CANSIGIO(), needs to be updated to use the p_cansignal() and
  p_cansched() centralized authorization routines, as they currently
  do not take into account some desirable restrictions that are handled
  by the centralized routines, as well as being inconsistent with other
  similar authorization instances.
o Update libkvm to take these changes into account.

Obtained from:	TrustedBSD Project
Reviewed by:	green, bde, jhb, freebsd-arch, freebsd-audit
2001-05-25 16:59:11 +00:00
Mark Murray
fb919e4d5a Undo part of the tangle of having sys/lock.h and sys/mutex.h included in
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)
2001-05-01 08:13:21 +00:00