Although POSIX literally permits failing with [EINVAL] if IPC_CREAT and
IPC_EXCL were both passed, the semaphore set already exists and has fewer
semaphores than nsems, this does not allow an application to retry safely:
if the [EINVAL] is actually because of the semmsl limit, an infinite loop
would result.
PR: 206927
The point of this is to be able to add RACCT (with RACCT_DISABLED)
to GENERIC, to avoid having to rebuild the kernel to use rctl(8).
Differential Revision: https://reviews.freebsd.org/D2369
Reviewed by: kib@
MFC after: 1 month
Relnotes: yes
Sponsored by: The FreeBSD Foundation
The kernel tracks syscall users so that modules can safely unregister them.
But if the module is not unloadable or was compiled into the kernel, there is
no need to do this.
Achieve this by adding SY_THR_STATIC_KLD macro which expands to SY_THR_STATIC
during kernel build and 0 otherwise.
Reviewed by: kib (previous version)
MFC after: 2 weeks
These changes prevent sysctl(8) from returning proper output,
such as:
1) no output from sysctl(8)
2) erroneously returning ENOMEM with tools like truss(1)
or uname(1)
truss: can not get etype: Cannot allocate memory
there is an environment variable which shall initialize the SYSCTL
during early boot. This works for all SYSCTL types both statically and
dynamically created ones, except for the SYSCTL NODE type and SYSCTLs
which belong to VNETs. A new flag, CTLFLAG_NOFETCH, has been added to
be used in the case a tunable sysctl has a custom initialisation
function allowing the sysctl to still be marked as a tunable. The
kernel SYSCTL API is mostly the same, with a few exceptions for some
special operations like iterating childrens of a static/extern SYSCTL
node. This operation should probably be made into a factored out
common macro, hence some device drivers use this. The reason for
changing the SYSCTL API was the need for a SYSCTL parent OID pointer
and not only the SYSCTL parent OID list pointer in order to quickly
generate the sysctl path. The motivation behind this patch is to avoid
parameter loading cludges inside the OFED driver subsystem. Instead of
adding special code to the OFED driver subsystem to post-load tunables
into dynamically created sysctls, we generalize this in the kernel.
Other changes:
- Corrected a possibly incorrect sysctl name from "hw.cbb.intr_mask"
to "hw.pcic.intr_mask".
- Removed redundant TUNABLE statements throughout the kernel.
- Some minor code rewrites in connection to removing not needed
TUNABLE statements.
- Added a missing SYSCTL_DECL().
- Wrapped two very long lines.
- Avoid malloc()/free() inside sysctl string handling, in case it is
called to initialize a sysctl from a tunable, hence malloc()/free() is
not ready when sysctls from the sysctl dataset are registered.
- Bumped FreeBSD version to indicate SYSCTL API change.
MFC after: 2 weeks
Sponsored by: Mellanox Technologies
patch modifies makesyscalls.sh to prefix all of the non-compatibility
calls (e.g. not linux_, freebsd32_) with sys_ and updates the kernel
entry points and all places in the code that use them. It also
fixes an additional name space collision between the kernel function
psignal and the libc function of the same name by renaming the kernel
psignal kern_psignal(). By introducing this change now we will ease future
MFCs that change syscalls.
Reviewed by: rwatson
Approved by: re (bz)
option that is highly recommended to be adjusted in too much
documentation while doing nothing in FreeBSD since r2729 (rev 1.1).
ipcs(1) needs to be recompiled as it is accessing _KERNEL private
variables.
Reviewed by: jhb (before comment change on linux code)
Sponsored by: Sandvine Incorporated
won't happen before 9.0. This commit adds "#ifdef RACCT" around all the
"PROC_LOCK(p); racct_whatever(p, ...); PROC_UNLOCK(p)" instances, in order
to avoid useless locking/unlocking in kernels built without "options RACCT".
for racct.
Note that after this commit, ipcs(1) needs to be rebuilt. Otherwise, it will
fail with "ipcs: sysctlbyname: kern.ipc.msqids: Cannot allocate memory".
Sponsored by: The FreeBSD Foundation
Reviewed by: kib (earlier version)
PMC/SYSV/...).
No FreeBSD version bump, the userland application to query the features will
be committed last and can serve as an indication of the availablility if
needed.
Sponsored by: Google Summer of Code 2010
Submitted by: kibab
Reviewed by: arch@ (parts by rwatson, trasz, jhb)
X-MFC after: to be determined in last commit with code from this project
shared resources defaults beyond absolute minimums.
The new values are chosen mostly by magic. They are still fairly
small and will need increasing for large installations (especially
SHMMAX). However, they are now enough to e.g. start PostgreSQL
installations with ~~300 users and nearly 512 MB of shared buffers.
Reviewed by: A short discussion on hackers@
sysv_{msg,sem,shm}.c files.
Mark SysV IPC freebsd32 syscalls as NOSTD and add required
SYSCALL_INIT_HELPER/SYSCALL32_INIT_HELPERs to provide auto
register/unregister on module load.
This makes COMPAT_FREEBSD32 functional with SysV IPC compiled and loaded
as modules.
Reviewed by: jhb
MFC after: 2 weeks
- The uid/cuid members of struct ipc_perm are now uid_t instead of unsigned
short.
- The gid/cgid members of struct ipc_perm are now gid_t instead of unsigned
short.
- The mode member of struct ipc_perm is now mode_t instead of unsigned short
(this is merely a style bug).
- The rather dubious padding fields for ABI compat with SV/I386 have been
removed from struct msqid_ds and struct semid_ds.
- The shm_segsz member of struct shmid_ds is now a size_t instead of an
int. This removes the need for the shm_bsegsz member in struct
shmid_kernel and should allow for complete support of SYSV SHM regions
>= 2GB.
- The shm_nattch member of struct shmid_ds is now an int instead of a
short.
- The shm_internal member of struct shmid_ds is now gone. The internal
VM object pointer for SHM regions has been moved into struct
shmid_kernel.
- The existing __semctl(), msgctl(), and shmctl() system call entries are
now marked COMPAT7 and new versions of those system calls which support
the new ABI are now present.
- The new system calls are assigned to the FBSD-1.1 version in libc. The
FBSD-1.0 symbols in libc now refer to the old COMPAT7 system calls.
- A simplistic framework for tagging system calls with compatibility
symbol versions has been added to libc. Version tags are added to
system calls by adding an appropriate __sym_compat() entry to
src/lib/libc/incldue/compat.h. [1]
PR: kern/16195 kern/113218 bin/129855
Reviewed by: arch@, rwatson
Discussed with: kan, kib [1]
them under COMPAT_FREEBSD[4567]. Starting with FreeBSD 5.0 the SYSV IPC
API was implemented via direct system calls (e.g. msgctl(), msgget(), etc.)
rather than indirecting through the var-args *sys() system calls. The
shmsys() system call was already effectively deprecated for all but
COMPAT_FREEBSD4 already as its implementation for the !COMPAT_FREEBSD4 case
was to simply invoke nosys().
and used in a large number of files, but also because an increasing number
of incorrect uses of MAC calls were sneaking in due to copy-and-paste of
MAC-aware code without the associated opt_mac.h include.
Discussed with: pjd
by creating a child jail, which is visible to that jail and to any
parent jails. Child jails may be restricted more than their parents,
but never less. Jail names reflect this hierarchy, being MIB-style
dot-separated strings.
Every thread now points to a jail, the default being prison0, which
contains information about the physical system. Prison0's root
directory is the same as rootvnode; its hostname is the same as the
global hostname, and its securelevel replaces the global securelevel.
Note that the variable "securelevel" has actually gone away, which
should not cause any problems for code that properly uses
securelevel_gt() and securelevel_ge().
Some jail-related permissions that were kept in global variables and
set via sysctls are now per-jail settings. The sysctls still exist for
backward compatibility, used only by the now-deprecated jail(2) system
call.
Approved by: bz (mentor)
guarantee atomicity of the operation for other semaphore consumers.
In particular, this should guard against access to the semaphore with
not done or partially done MAC label assignment.
Reviewed by: rwatson
MFC after: 1 month
on SysV semaphores.
The squeeze of the semaphore array in the kern_semctl() modifies
sem_base for the semaphores with sem_base greater then sem_base of
the removed semaphore, as well as the values of the semaphores,
without locking their mutex. This can lead to (killable) hangs or
unexpected behaviour of the processes performing any sem operations
while other process does IPC_RMID.
The semexit_myhook() eventhandler unlocks SEMUNDO_LOCK() while
accessing *suptr. This allows for IPC_RMID for the sem id to be
performed in parallel with undo hook referenced by the current undo
structure. This leads to the panic("semexit - semid not allocated") [1].
The semaphore creation is protected by Giant, while IPC_RMID is done
while only semaphore mutex is held. This seems to result in invalid
values for semtot, causing random ENOSPC error returns [2].
Redo the locking of the semaphores lifetime cycle. Delegate the
sem_mtx to the sole purpose of protecting semget() and
semctl(IPC_RMID). Introduce new sem_undo_mtx to protect SEM_UNDO
handling. Remove the Giant remnants from the code.
Note that mac_sysvsem_check_semget() and mac_sysvsem_create() are
now called while sem_mtx is held, as well as mac_sysvsem_cleanup() [3].
When semaphore is removed, acquire semaphore locks for all semaphores
with sem_base that is going to be changed by squeeze of the sema
array. The lock order is not important there, because the region is
protected by sem_mtx.
Organize both used and free sem_undo structures into the lists,
protected by sem_undo_mtx. In semexit_myhook(), remove sem_undo
structure that is being processed, from used list, without putting it
onto the free to prevent modifications by other threads. This allows
for sem_undo_lock to be dropped to acquire individial semaphore locks
without violating lock order. Since IPC_RMID may no longer find this
sem_undo, do tolerate references to unallocated semaphores in undo
structure, and check sequential number to not undo unrelated semaphore
with the same id.
While there, convert functions definitions to ANSI C and fix small
style(9) glitches.
Reported by: Omer Faruk Sen <omerfsen gmail com> [1], pho [2]
Reviewed by: rwatson [3]
Tested by: pho
MFC after: 1 month
from Mac OS X Leopard--rationalize naming for entry points to
the following general forms:
mac_<object>_<method/action>
mac_<object>_check_<method/action>
The previous naming scheme was inconsistent and mostly
reversed from the new scheme. Also, make object types more
consistent and remove spaces from object types that contain
multiple parts ("posix_sem" -> "posixsem") to make mechanical
parsing easier. Introduce a new "netinet" object type for
certain IPv4/IPv6-related methods. Also simplify, slightly,
some entry point names.
All MAC policy modules will need to be recompiled, and modules
not updates as part of this commit will need to be modified to
conform to the new KPI.
Sponsored by: SPARTA (original patches against Mac OS X)
Obtained from: TrustedBSD Project, Apple Computer
- Remove also "MP SAFE" after prior "MPSAFE" pass. (suggested by bde)
- Remove extra blank lines in some cases.
- Add extra blank lines in some cases.
- Remove no-op comments consisting solely of the function name, the word
"syscall", or the system call name.
- Add punctuation.
- Re-wrap some comments.
system calls now enter without Giant held, and then in some cases, acquire
Giant explicitly.
Remove a number of other MPSAFE annotations in the credential code and
tweak one or two other adjacent comments.
begun with a repo-copy of mac.h to mac_framework.h. sys/mac.h now
contains the userspace and user<->kernel API and definitions, with all
in-kernel interfaces moved to mac_framework.h, which is now included
across most of the kernel instead.
This change is the first step in a larger cleanup and sweep of MAC
Framework interfaces in the kernel, and will not be MFC'd.
Obtained from: TrustedBSD Project
Sponsored by: SPARTA
appears to be serving a useful purpose, as it was used during initial
development of MAC support for System V IPC.
MFC after: 1 month
Obtained from: TrustedBSD Project
Suggested by: Christopher dot Vance at SPARTA dot com
mostly consists of pushing a few copyin's and copyout's up into
__semctl() as all the other callers were already doing the UIO_SYSSPACE
case. This also changes kern_semctl() to set the return value in a passed
in pointer to a register_t rather than td->td_retval[0] directly so that
callers can only set td->td_retval[0] if all the various copyout's succeed.
As a result of these changes, kern_semctl() no longer does copyin/copyout
(except for GETALL/SETALL) so simplify the locking to acquire the semakptr
mutex before the MAC check and hold it all the way until the end of the
big switch statement. The GETALL/SETALL cases have to temporarily drop it
while they do copyin/malloc and copyout. Also, simplify the SETALL case to
remove handling for a non-existent race condition.
a local 'semid' variable which was the array index and used uap->semid
as the original IPC id. During the kern_semctl() conversion those two
variables were collapsed into a single 'semid' variable breaking the
places that needed the original IPC ID. To fix, add a new 'semidx'
variable to hold the array index and leave 'semid' unmolested as the IPC
id. While I'm here, explicitly document that the (undocumented, at least
in semctl(2)) SEM_STAT command curiously expects an array index in the
'semid' parameter rather than an IPC id.
Submitted by: maxim
to a copied-in copy of the 'union semun' and a uioseg to indicate which
memory space the 'buf' pointer of the union points to. This is then used
in linux_semctl() and svr4_sys_semctl() to eliminate use of the stackgap.
- Mark linux_ipc() and svr4_sys_semsys() MPSAFE.
- Move sonewconn(), which creates new sockets for incoming connections on
listen sockets, so that all socket allocate code is together in
uipc_socket.c.
- Move 'maxsockets' and associated sysctls to uipc_socket.c with the
socket allocation code.
- Move kern.ipc sysctl node to uipc_socket.c, add a SYSCTL_DECL() for it
to sysctl.h and remove lots of scattered implementations in various
IPC modules.
- Sort sodealloc() after soalloc() in uipc_socket.c for dependency order
reasons. Statisticize soalloc() and sodealloc() as they are now
required only in uipc_socket.c, and are internal to the socket
implementation.
After this change, socket allocation and deallocation is entirely
centralized in one file, and uipc_socket2.c consists entirely of socket
buffer manipulation and default protocol switch functions.
MFC after: 1 month
points to convert _sema() to _sem() for consistency purposes with
respect to the other semaphore-related entry points:
mac_init_sysv_sema() -> mac_init_sysv_sem()
mac_destroy_sysv_sem() -> mac_destroy_sysv_sem()
mac_create_sysv_sema() -> mac_create_sysv_sem()
mac_cleanup_sysv_sema() -> mac_cleanup_sysv_sem()
Congruent changes are made to the policy interface to support this.
Obtained from: TrustedBSD Project
Sponsored by: SPAWAR, SPARTA
This information will be very useful for people who are tuning applications
which have a dependence on IPC mechanisms.
The following OIDs were documented:
Message queues:
kern.ipc.msgmax
kern.ipc.msgmni
kern.ipc.msgmnb
kern.ipc.msgtlq
kern.ipc.msgssz
kern.ipc.msgseg
Semaphores:
kern.ipc.semmap
kern.ipc.semmni
kern.ipc.semmns
kern.ipc.semmnu
kern.ipc.semmsl
kern.ipc.semopm
kern.ipc.semume
kern.ipc.semusz
kern.ipc.semvmx
kern.ipc.semaem
Shared memory:
kern.ipc.shmmax
kern.ipc.shmmin
kern.ipc.shmmni
kern.ipc.shmseg
kern.ipc.shmall
kern.ipc.shm_use_phys
kern.ipc.shm_allow_removed
kern.ipc.shmsegs
These new descriptions can be viewed using sysctl -d
PR: kern/65219
Submitted by: Dan Nelson <dnelson at allantgroup dot com> (modified)
No objections: developers@
Descriptions reviewed by: gnn
MFC after: 1 week
return EINVAL rather than setting error, and don't free sops
unconditionally. The first change was merged accidentally as part of
the larger set of changes to introduce MAC labels and access control,
and potentially lead to continued processing of a request even after
it was determined to be invalid. The second change was due to changes
in the semaphore code since the original work was performed.
Pointed out by: truckman
to be modified and extended without breaking the user space ABI:
Use _kernel variants on _ds structures for System V sempahores, message
queues, and shared memory. When interfacing with userspace, export
only the _ds subsets of the _kernel data structures. A lot of search
and replace.
Define the message structure in the _KERNEL portion of msg.h so that it
can be used by other kernel consumers, but not exposed to user space.
Submitted by: Dandekar Hrishikesh <rishi_dandekar at sbcglobal dot net>
Obtained from: TrustedBSD Project
Sponsored by: DARPA, SPAWAR, McAfee Research
