Commit Graph

100 Commits

Author SHA1 Message Date
Alan Cox
60bb39431a Maintain the lock on the vnode for most of exec_elfN_imgact().
Specifically, it is required for the I/O that may be performed by
elfN_load_section().

Avoid an obscure deadlock in the a.out, elf, and gzip image
activators.  Add a comment describing why the deadlock does not occur
in the common case and how it might occur in less usual circumstances.

Eliminate an unused variable from exec_aout_imgact().

In collaboration with: tegge
2005-12-24 04:57:50 +00:00
Jeff Roberson
e11a45c9e5 - Neither of our image formats require Giant now that the vm and vfs have
been locked.
2005-05-03 10:51:38 +00:00
Maxim Sobolev
610ecfe035 o Split out kernel part of execve(2) syscall into two parts: one that
copies arguments into the kernel space and one that operates
  completely in the kernel space;

o use kernel-only version of execve(2) to kill another stackgap in
  linuxlator/i386.

Obtained from:  DragonFlyBSD (partially)
MFC after:      2 weeks
2005-01-29 23:12:00 +00:00
Warner Losh
9454b2d864 /* -> /*- for copyright notices, minor format tweaks as necessary 2005-01-06 23:35:40 +00:00
David Schultz
1eecfae3e5 Axe a.out core dump support. Neither older gdb binaries nor current
bfd sources understand the present format.
2004-11-27 06:46:59 +00:00
David Schultz
0ef5c36ff1 Maintain the broken state of backwards compatibilty for a.out (and
PECOFF!) core dumps.  None of the old versions of gdb I tried were
able to read a.out core dumps before or after this change.

Reviewed by:	arch@
2004-11-20 02:32:04 +00:00
Tim J. Robbins
f99619a0dc Change the types of vn_rdwr_inchunks()'s len and aresid arguments to
size_t and size_t *, respectively. Update callers for the new interface.
This is a better fix for overflows that occurred when dumping segments
larger than 2GB to core files.
2004-06-05 02:18:28 +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
Peter Wemm
c460ac3a00 Add sysentvec->sv_fixlimits() hook so that we can catch cases on 64 bit
systems where the data/stack/etc limits are too big for a 32 bit process.

Move the 5 or so identical instances of ELF_RTLD_ADDR() into imgact_elf.c.

Supply an ia32_fixlimits function.  Export the clip/default values to
sysctl under the compat.ia32 heirarchy.

Have mmap(0, ...) respect the current p->p_limits[RLIMIT_DATA].rlim_max
value rather than the sysctl tweakable variable.  This allows mmap to
place mappings at sensible locations when limits have been reduced.

Have the imgact_elf.c ld-elf.so.1 placement algorithm use the same
method as mmap(0, ...) now does.

Note that we cannot remove all references to the sysctl tweakable
maxdsiz etc variables because /etc/login.conf specifies a datasize
of 'unlimited'.  And that causes exec etc to fail since it can no
longer find space to mmap things.
2003-09-25 01:10:26 +00:00
David E. O'Brien
677b542ea2 Use __FBSDID(). 2003-06-11 00:56:59 +00:00
Warner Losh
a163d034fa Back out M_* changes, per decision of the TRB.
Approved by: trb
2003-02-19 05:47:46 +00:00
Alfred Perlstein
44956c9863 Remove M_TRYWAIT/M_WAITOK/M_WAIT. Callers should use 0.
Merge M_NOWAIT/M_DONTWAIT into a single flag M_NOWAIT.
2003-01-21 08:56:16 +00:00
Jake Burkholder
05ba50f522 Use the fields in the sysentvec and in the vm map header in place of the
constants VM_MIN_ADDRESS, VM_MAXUSER_ADDRESS, USRSTACK and PS_STRINGS.
This is mainly so that they can be variable even for the native abi, based
on different machine types.  Get stack protections from the sysentvec too.
This makes it trivial to map the stack non-executable for certain abis, on
machines that support it.
2002-09-21 22:07:17 +00:00
Bruce Evans
e5d6cd0c98 Include <sys/malloc.h> instead of depending on namespace pollution 2
layers deep in <sys/proc.h> or <sys/vnode.h>.

Removed unused includes.  Sorted includes.
2002-09-10 11:57:02 +00:00
Peter Wemm
a9f9df5daf Tidy up some loose ends that bde pointed out. caddr_t bad, ok?
Move fill_kinfo_proc to before we copy the results instead of after
the copy and too late.

There is still more to do here.
2002-09-07 22:31:44 +00:00
Peter Wemm
99a17113cd The true value of how the kernel was configured for KSTACK_PAGES was not
available at module compile time.  Do not #include the bogus
opt_kstack_pages.h at this point and instead refer to the variables that
are also exported via sysctl.
2002-09-07 22:15:47 +00:00
Peter Wemm
710ded3ac5 Collect the a.out coredump code into the calling functions.
XXX why does pecoff dump in a.out format?
2002-09-07 01:23:51 +00:00
Jake Burkholder
f36ba45234 Added fields for VM_MIN_ADDRESS, PS_STRINGS and stack protections to
sysentvec.  Initialized all fields of all sysentvecs, which will allow
them to be used instead of constants in more places.  Provided stack
fixup routines for emulations that previously used the default.
2002-09-01 21:41:24 +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
Jeff Roberson
619eb6e579 - Hold the vnode lock throughout execve.
- Set VV_TEXT in the top level execve code.
 - Fixup the image activators to deal with the newly locked vnode.
2002-08-13 06:55:28 +00:00
Jeff Roberson
e6e370a7fe - Replace v_flag with v_iflag and v_vflag
- v_vflag is protected by the vnode lock and is used when synchronization
   with VOP calls is needed.
 - v_iflag is protected by interlock and is used for dealing with vnode
   management issues.  These flags include X/O LOCK, FREE, DOOMED, etc.
 - All accesses to v_iflag and v_vflag have either been locked or marked with
   mp_fixme's.
 - Many ASSERT_VOP_LOCKED calls have been added where the locking was not
   clear.
 - Many functions in vfs_subr.c were restructured to provide for stronger
   locking.

Idea stolen from:	BSD/OS
2002-08-04 10:29:36 +00:00
Peter Wemm
3ebc124838 Infrastructure tweaks to allow having both an Elf32 and an Elf64 executable
handler in the kernel at the same time.  Also, allow for the
exec_new_vmspace() code to build a different sized vmspace depending on
the executable environment.  This is a big help for execing i386 binaries
on ia64.   The ELF exec code grows the ability to map partial pages when
there is a page size difference, eg: emulating 4K pages on 8K or 16K
hardware pages.

Flesh out the i386 emulation support for ia64.  At this point, the only
binary that I know of that fails is cvsup, because the cvsup runtime
tries to execute code in pages not marked executable.

Obtained from:  dfr (mostly, many tweaks from me).
2002-07-20 02:56:12 +00:00
Jeff Roberson
0b2ed1aef7 Clean up execve locking:
- Grab the vnode object early in exec when we still have the vnode lock.
 - Cache the object in the image_params.
 - Make use of the cached object in imgact_*.c
2002-07-06 07:00:01 +00:00
John Baldwin
65c9b4303b - Change fill_kinfo_proc() to require that the process is locked when it
is called.
- Change sysctl_out_proc() to require that the process is locked when it
  is called and to drop the lock before it returns.  If this proves too
  complex we can change sysctl_out_proc() to simply acquire the lock at
  the very end and have the calling code drop the lock right after it
  returns.
- Lock the process we are going to export before the p_cansee() in the
  loop in sysctl_kern_proc() and hold the lock until we call
  sysctl_out_proc().
- Don't call p_cansee() on the process about to be exported twice in
  the aforementioned loop.
2002-04-09 20:10:46 +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
Paul Saab
cbc89bfbfe Make MAXTSIZ, DFLDSIZ, MAXDSIZ, DFLSSIZ, MAXSSIZ, SGROWSIZ loader
tunable.

Reviewed by:	peter
MFC after:	2 weeks
2001-10-10 23:06:54 +00:00
Matthew Dillon
3418ebebfe Make uio_yield() a global. Call uio_yield() between chunks
in vn_rdwr_inchunks(), allowing other processes to gain an exclusive
lock on the vnode.  Specifically: directory scanning, to avoid a race to the
root directory, and multiple child processes coring simultaniously so they
can figure out that some other core'ing child has an exclusive adv lock and
just exit instead.

This completely fixes performance problems when large programs core.  You
can have hundreds of copies (forked children) of the same binary core all
at once and not notice.

MFC after:	3 days
2001-09-26 06:54:32 +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
06ae1e91c4 This brings in a Yahoo coredump patch from Paul, with additional mods by
me (addition of vn_rdwr_inchunks).  The problem Yahoo is solving is that
if you have large process images core dumping, or you have a large number of
forked processes all core dumping at the same time, the original coredump code
would leave the vnode locked throughout.  This can cause the directory vnode
to get locked up, which can cause the parent directory vnode to get locked
up, and so on all the way to the root node, locking the entire machine up
for extremely long periods of time.

This patch solves the problem in two ways.  First it uses an advisory
non-blocking lock to abort multiple processes trying to core to the same
file.  Second (my contribution) it chunks up the writes and uses bwillwrite()
to avoid holding the vnode locked while blocking in the buffer cache.

Submitted by:	ps
Reviewed by:	dillon
MFC after:	2 weeks
2001-09-08 20:02:33 +00:00
Peter Wemm
268bdb43f9 Optionize UPAGES for the i386. As part of this I split some of the low
level implementation stuff out of machine/globaldata.h to avoid exposing
UPAGES to lots more places.  The end result is that we can double
the kernel stack size with 'options UPAGES=4' etc.

This is mainly being done for the benefit of a MFC to RELENG_4 at some
point.  -current doesn't really need this so much since each interrupt
runs on its own kstack.
2001-08-25 02:20:02 +00:00
Matthew Dillon
0cddd8f023 With Alfred's permission, remove vm_mtx in favor of a fine-grained approach
(this commit is just the first stage).  Also add various GIANT_ macros to
formalize the removal of Giant, making it easy to test in a more piecemeal
fashion. These macros will allow us to test fine-grained locks to a degree
before removing Giant, and also after, and to remove Giant in a piecemeal
fashion via sysctl's on those subsystems which the authors believe can
operate without Giant.
2001-07-04 16:20:28 +00:00
Alfred Perlstein
2395531439 Introduce a global lock for the vm subsystem (vm_mtx).
vm_mtx does not recurse and is required for most low level
vm operations.

faults can not be taken without holding Giant.

Memory subsystems can now call the base page allocators safely.

Almost all atomic ops were removed as they are covered under the
vm mutex.

Alpha and ia64 now need to catch up to i386's trap handlers.

FFS and NFS have been tested, other filesystems will need minor
changes (grabbing the vm lock when twiddling page properties).

Reviewed (partially) by: jake, jhb
2001-05-19 01:28:09 +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
John Baldwin
ba88dfc733 Back out proc locking to protect p_ucred for obtaining additional
references along with the actual obtaining of additional references.
2001-01-27 00:01:31 +00:00
John Baldwin
611d940790 Proc locking. 2001-01-24 00:27:28 +00:00
Kirk McKusick
1f7d250182 Change the proc information returned from the kernel so that it
no longer contains kernel specific data structures, but rather
only scalar values and structures that are already part of the
kernel/user interface, specifically rusage and rtprio. It no
longer contains proc, session, pcred, ucred, procsig, vmspace,
pstats, mtx, sigiolst, klist, callout, pasleep, or mdproc. If
any of these changed in size, ps, w, fstat, gcore, systat, and
top would all stop working. The new structure has over 200 bytes
of unassigned space for future values to be added, yet is nearly
100 bytes smaller per entry than the structure that it replaced.
2000-12-12 07:25:57 +00:00
Marcel Moolenaar
806d7daafe Make MINSIGSTKSZ machine dependent, and have the sigaltstack
syscall compare against a variable sv_minsigstksz in struct
sysentvec as to properly take the size of the machine- and
ABI dependent struct sigframe into account.

The SVR4 and iBCS2 modules continue to have a minsigstksz of
8192 to preserve behavior. The real values (if different) are
not known at this time. Other ABI modules use the real
values.

The native MINSIGSTKSZ is now defined as follows:

Arch		MINSIGSTKSZ
----		-----------
alpha		    4096
i386		    2048
ia64		   12288

Reviewed by: mjacob
Suggested by: bde
2000-11-09 08:25:48 +00:00
Boris Popov
9ff5ce6baf Add three new VOPs: VOP_CREATEVOBJECT, VOP_DESTROYVOBJECT and VOP_GETVOBJECT.
They will be used by nullfs and other stacked filesystems to support full
cache coherency.

Reviewed in general by:	mckusick, dillon
2000-09-12 09:49:08 +00:00
Doug Rabson
21ac8e0b77 Move the include of <sys/systm.h> so that KTR gets a declaration for
snprintf().
2000-09-10 13:33:31 +00:00
Poul-Henning Kamp
3389ae9350 Remove ~25 unneeded #include <sys/conf.h>
Remove ~60 unneeded #include <sys/malloc.h>
2000-04-19 14:58:28 +00:00
Poul-Henning Kamp
da654d9070 s/p_cred->pc_ucred/p_ucred/g 1999-11-21 12:38:21 +00:00
Poul-Henning Kamp
923502ff91 useracc() the prequel:
Merge the contents (less some trivial bordering the silly comments)
of <vm/vm_prot.h> and <vm/vm_inherit.h> into <vm/vm.h>.  This puts
the #defines for the vm_inherit_t and vm_prot_t types next to their
typedefs.

This paves the road for the commit to follow shortly: change
useracc() to use VM_PROT_{READ|WRITE} rather than B_{READ|WRITE}
as argument.
1999-10-29 18:09:36 +00:00
Peter Wemm
d1f088dab5 Trim unused options (or #ifdef for undoc options).
Submitted by:	phk
1999-10-11 15:19:12 +00:00
Bruce Evans
b9e91a85a6 Fixed style regressions in previous commit. 1999-09-04 13:30:18 +00:00
Julian Elischer
fca666a142 General cleanup of core-dumping code.
Submitted by: Sean Fagan,
1999-09-01 00:29:56 +00:00
Peter Wemm
c3aac50f28 $Id$ -> $FreeBSD$ 1999-08-28 01:08:13 +00:00
Dima Ruban
d44e415624 Don't follow symlinks on coredumps.
Reviewed by:	dillon && security-officer
1999-08-26 17:32:48 +00:00
Alan Cox
e972780a11 Add the options MAP_PREFAULT and MAP_PREFAULT_PARTIAL to vm_map_find/insert,
eliminating the need for the pmap_object_init_pt calls in imgact_* and
mmap.

Reviewed by:	David Greenman <dg@root.com>
1999-05-17 00:53:56 +00:00
Alan Cox
e5f13bdd09 Simplify vm_map_find/insert's interface: remove the MAP_COPY_NEEDED option.
It never makes sense to specify MAP_COPY_NEEDED without also specifying
MAP_COPY_ON_WRITE, and vice versa.  Thus, MAP_COPY_ON_WRITE suffices.

Reviewed by:	David Greenman <dg@root.com>
1999-05-14 23:09:34 +00:00