use the ability on ia64 to map the register stack. The orientation of
the stack (i.e. its grow direction) is passed to vm_map_stack() in the
overloaded cow argument. Since the grow direction is represented by
bits, it is possible and allowed to create bi-directional stacks.
This is not an advertised feature, more of a side-effect.
Fix a bug in vm_map_growstack() that's specific to rstacks and which
we could only find by having the ability to create rstacks: when
the mapped stack ends at the faulting address, we have not actually
mapped the faulting address. we need to include or cover the faulting
address.
Note that at this time mmap(2) has not been extended to allow the
creation of rstacks by processes. If such a need arises, this can
be done.
Tested on: alpha, i386, ia64, sparc64
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.
contain the filedescriptor number on opens from userland.
The index is used rather than a "struct file *" since it conveys a bit
more information, which may be useful to in particular fdescfs and /dev/fd/*
For now pass -1 all over the place.
- Move struct sigacts out of the u-area and malloc() it using the
M_SUBPROC malloc bucket.
- Add a small sigacts_*() API for managing sigacts structures: sigacts_alloc(),
sigacts_free(), sigacts_copy(), sigacts_share(), and sigacts_shared().
- Remove the p_sigignore, p_sigacts, and p_sigcatch macros.
- Add a mutex to struct sigacts that protects all the members of the struct.
- Add sigacts locking.
- Remove Giant from nosys(), kill(), killpg(), and kern_sigaction() now
that sigacts is locked.
- Several in-kernel functions such as psignal(), tdsignal(), trapsignal(),
and thread_stopped() are now MP safe.
Reviewed by: arch@
Approved by: re (rwatson)
if (p->p_numthreads > 1) and not a flag because action is only necessary
if there are other threads. The rest of the system has no need to
identify thr threaded processes.
- In kern_thread.c use thr_exit1() instead of thread_exit() if P_THREADED
is not set.
flexible process_fork, process_exec, and process_exit eventhandlers. This
reduces code duplication and also means that I don't have to go duplicate
the eventhandler locking three more times for each of at_fork, at_exec, and
at_exit.
Reviewed by: phk, jake, almost complete silence on arch@
struct proc as p_tracecred alongside the current cache of the vnode in
p_tracep. This credential is then used for all later ktrace operations on
this file rather than using the credential of the current thread at the
time of each ktrace event.
- Now that we have multiple ktrace-related items in struct proc that are
pointers, rename p_tracep to p_tracevp to make it less ambiguous.
Requested by: rwatson (1)
I'm not convinced there is anything major wrong with the patch but
them's the rules..
I am using my "David's mentor" hat to revert this as he's
offline for a while.
data structure called kse_upcall to manage UPCALL. All KSE binding
and loaning code are gone.
A thread owns an upcall can collect all completed syscall contexts in
its ksegrp, turn itself into UPCALL mode, and takes those contexts back
to userland. Any thread without upcall structure has to export their
contexts and exit at user boundary.
Any thread running in user mode owns an upcall structure, when it enters
kernel, if the kse mailbox's current thread pointer is not NULL, then
when the thread is blocked in kernel, a new UPCALL thread is created and
the upcall structure is transfered to the new UPCALL thread. if the kse
mailbox's current thread pointer is NULL, then when a thread is blocked
in kernel, no UPCALL thread will be created.
Each upcall always has an owner thread. Userland can remove an upcall by
calling kse_exit, when all upcalls in ksegrp are removed, the group is
atomatically shutdown. An upcall owner thread also exits when process is
in exiting state. when an owner thread exits, the upcall it owns is also
removed.
KSE is a pure scheduler entity. it represents a virtual cpu. when a thread
is running, it always has a KSE associated with it. scheduler is free to
assign a KSE to thread according thread priority, if thread priority is changed,
KSE can be moved from one thread to another.
When a ksegrp is created, there is always N KSEs created in the group. the
N is the number of physical cpu in the current system. This makes it is
possible that even an userland UTS is single CPU safe, threads in kernel still
can execute on different cpu in parallel. Userland calls kse_create to add more
upcall structures into ksegrp to increase concurrent in userland itself, kernel
is not restricted by number of upcalls userland provides.
The code hasn't been tested under SMP by author due to lack of hardware.
Reviewed by: julian
dereferenced when a process exits due to the vmspace ref-count being
bumped. Change shmexit() and shmexit_myhook() to take a vmspace instead
of a process and call it in vmspace_dofree(). This way if it is missed
in exit1()'s early-resource-free it will still be caught when the zombie is
reaped.
Also fix a potential race in shmexit_myhook() by NULLing out
vmspace->vm_shm prior to calling shm_delete_mapping() and free().
MFC after: 7 days
On architectures with a non-executable stack, eg sparc64, this is used by
libgcc to determine at runtime if its necessary to enable execute permissions
on a region of the stack which will be used to execute code, allowing the
call to mprotect to be avoided if the kernel is configured to map the stack
executable.
problem was a locked directory vnode), do not give the process a chance
to sleep in state "stopevent" (depends on the S_EXEC bit being set in
p_stops) until most resources have been released again.
Approved by: re
indirectly through vm_page_protect(). The one remaining page flag that
is updated by vm_page_protect() is already being updated by our various
pmap implementations.
Note: A later commit will similarly change the VM_PROT_READ case and
eliminate vm_page_protect().
(1) Permit userland applications to request a change of label atomic
with an execve() via mac_execve(). This is required for the
SEBSD port of SELinux/FLASK. Attempts to invoke this without
MAC compiled in result in ENOSYS, as with all other MAC system
calls. Complexity, if desired, is present in policy modules,
rather than the framework.
(2) Permit policies to have access to both the label of the vnode
being executed as well as the interpreter if it's a shell
script or related UNIX nonsense. Because we can't hold both
vnode locks at the same time, cache the interpreter label.
SEBSD relies on this because it supports secure transitioning
via shell script executables. Other policies might want to
take both labels into account during an integrity or
confidentiality decision at execve()-time.
Approved by: re
Obtained from: TrustedBSD Project
Sponsored by: DARPA, Network Associates Laboratories
entrypoints, #ifdef MAC. The supporting logic already existed in
kern_mac.c, so no change there. This permits MAC policies to cause
a process label change as the result of executing a binary --
typically, as a result of executing a specially labeled binary.
For example, the SEBSD port of SELinux/FLASK uses this functionality
to implement TE type transitions on processes using transitioning
binaries, in a manner similar to setuid. Policies not implementing
a notion of transition (all the ones in the tree right now) require
no changes, since the old label data is copied to the new label
via mac_create_cred() even if a transition does occur.
Obtained from: TrustedBSD Project
Sponsored by: DARPA, Network Associates Laboratories
describes an image activation instance. Instead, make use of the
existing fname structure entry, and introduce two new entries,
userspace_argv, and userspace_envv. With the addition of
mac_execve(), this divorces the image structure from the specifics
of the execve() system call, removes a redundant pointer, etc.
No semantic change from current behavior, but it means that the
structure doesn't depend on syscalls.master-generated includes.
There seems to be some redundant initialization of imgact entries,
which I have maintained, but which could probably use some cleaning
up at some point.
Obtained from: TrustedBSD Project
Sponsored by: DARPA, Network Associates Laboratories
the locking of the proc lock after the goto to done1 to avoid locking
the lock in an error case just so we can turn around and unlock it.
- Move the exec_setregs() stuff out from under the proc lock and after
the p_args stuff. This allows exec_setregs() to be able to sleep or
write things out to userland, etc. which ia64 does.
Tested by: peter
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.
recursion when closef() calls pfind() which also wants the proc lock.
This case only occurred when setugidsafety() needed to close unsafe files.
Reviewed by: truckman
s/SNGL/SINGLE/
s/SNGLE/SINGLE/
Fix abbreviation for P_STOPPED_* etc flags, in original code they were
inconsistent and difficult to distinguish between them.
Approved by: julian (mentor)
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.
kernel access control.
Invoke an appropriate MAC entry point to authorize execution of
a file by a process. The check is placed slightly differently
than it appears in the trustedbsd_mac tree so that it prevents
a little more information leakage about the target of the execve()
operation.
Obtained from: TrustedBSD Project
Sponsored by: DARPA, NAI Labs
