can be called both with and without the pipe mutex held. (For example,
if called by pipeselwakeup(), it is held. Whereas, if called by kqueue_scan(),
it is not.)
Reviewed by: alfred
There is still some locations where the PROC lock should be held
in order to prevent inconsistent views from outside (like the
proc->p_fd fix for kern/vfs_syscalls.c:checkdirs()) that can be
fixed later.
Submitted by: Jonathan Mini <mini@haikugeek.com>
with this flag. Remove the dup_list and dup_ok code from subr_witness. Now
we just check for the flag instead of doing string compares.
Also, switch the process lock, process group lock, and uma per cpu locks over
to this interface. The original mechanism did not work well for uma because
per cpu lock names are unique to each zone.
Approved by: jhb
disablement assumptions in kern_fork.c by adding another API call,
cpu_critical_fork_exit(). Cleanup the td_savecrit field by moving it
from MI to MD. Temporarily move cpu_critical*() from <arch>/include/cpufunc.h
to <arch>/<arch>/critical.c (stage-2 will clean this up).
Implement interrupt deferral for i386 that allows interrupts to remain
enabled inside critical sections. This also fixes an IPI interlock bug,
and requires uses of icu_lock to be enclosed in a true interrupt disablement.
This is the stage-1 commit. Stage-2 will occur after stage-1 has stabilized,
and will move cpu_critical*() into its own header file(s) + other things.
This commit may break non-i386 architectures in trivial ways. This should
be temporary.
Reviewed by: core
Approved by: core
- return error -> return (error);
- move a declaration to the top of the function.
- become bug for bug compatible with if (error) lines.
Submitted by: bde
new vfs_getopt()/vfs_copyopt() API. This is intended to be used
later, when there will be filesystems implementing the VFS_NMOUNT
operation. The mount(2) system call will disappear when all
filesystems will be converted to the new API. Documentation will
be committed in a while.
Reviewed by: phk
modules (ie. procfs.ko).
When the kernel loads dynamic filesystem module, it looks for any of the
VOP operations specified by the new filesystem that have not been registered
already by the currently known filesystems. If any of such operations exist,
vfs_add_vnops function calls vfs_opv_recalc function, which rebuilds vop_t
vectors for each filesystem and sets all global pointers like ufs_vnops_p,
devfs_specop_p, etc to the new values and then frees the old pointers. This
behavior is bad because there might be already active vnodes whose v_op fields
will be left pointing to the random garbage, leading to inevitable crash soon.
Submitted by: Alexander Kabaev <ak03@gte.com>
kern_linker.c and rev. 1.237 of vfs_syscalls.c since these are not the
source of the recent panics occuring around kldloading file system
support modules.
Requested by: rwatson
not removing tabs before "__P((", and not outdenting continuation lines
to preserve non-KNF lining up of code with parentheses. Switch to KNF
formatting and/or rewrap the whole prototype in some cases.
code that is still not safe. suser() reads p_ucred so it still needs
Giant for the time being. This should allow kern.giant.proc to be set
to 0 for the time being.
Move the network code from using cr_cansee() to check whether a
socket is visible to a requesting credential to using a new
function, cr_canseesocket(), which accepts a subject credential
and object socket. Implement cr_canseesocket() so that it does a
prison check, a uid check, and add a comment where shortly a MAC
hook will go. This will allow MAC policies to seperately
instrument the visibility of sockets from the visibility of
processes.
Obtained from: TrustedBSD Project
Sponsored by: DARPA, NAI Labs
to test req->td for NULL values and then do somewhat more bizarre things
relating to securelevel special-casing and suser checks. Remove the
testing and conditional security checks based on req->td!=NULL, and insert
a KASSERT that td != NULL. Callers to sysctl must always specify the
thread (be it kernel or otherwise) requesting the operation, or a
number of current sysctls will fail due to assumptions that the thread
exists.
Obtained from: TrustedBSD Project
Sponsored by: DARPA, NAI Labs
Discussed with: bde
NULL, turn warning printf's into panic's, since this call has been
restructured such that a NULL cred would result in a page fault anyway.
There appears to be one case where NULL is explicitly passed in in the
sysctl code, and this is believed to be in error, so will be modified.
Securelevels now always require a credential context so that per-jail
securelevels are properly implemented.
Obtained from: TrustedBSD Project
Sponsored by: NAI Labs
Discussed with: bde
made aware in jail environments. Supposedly something is broken, so
this should be backed out until further investigation proves otherwise,
or a proper fix can be provided.
method-based inter-process security checks. To do this, introduce
a new cr_seeotheruids(u1, u2) function, which encapsulates the
"see_other_uids" logic. Call out to this policy following the
jail security check for all of {debug,sched,see,signal} inter-process
checks. This more consistently enforces the check, and makes the
check easy to modify. Eventually, it may be that this check should
become a MAC policy, loaded via a module.
Obtained from: TrustedBSD Project
Sponsored by: DARPA, NAI Labs
Instead of caching the ucred reference, just go ahead and eat the
decerement and increment of the refcount. Now that Giant is pushed down
into crfree(), we no longer have to get Giant in the common case. In the
case when we are actually free'ing the ucred, we would normally free it on
the next kernel entry, so the cost there is not new, just in a different
place. This also removse td_cache_ucred from struct thread. This is
still only done #ifdef DIAGNOSTIC.
[ missed this file in the previous commit ]
Tested on: i386, alpha
- Add a cred_free_thread() function (conditional on DIAGNOSTICS) that drops
a per-thread ucred reference to be used in debugging code when leaving
the kernel.
against users within a jail attempting to load kernel modules.
- Add a check of securelevel_gt() to vfs_mount() in order to chop some
low hanging fruit for the repair of securelevel checking of linking and
unlinking files from within jails. There is more to be done here.
Reviewed by: rwatson
all the global bits of ``module'' data. This commit adds a few generic
macros, MOD_SLOCK, MOD_XLOCK, etc., that are meant to be used as ways
of accessing the SX lock. It is also the first step in helping to lock
down the kernel linker and module systems.
Reviewed by: jhb, jake, smp@
locking flags when acquiring a vnode. The immediate purpose is
to allow polling lock requests (LK_NOWAIT) needed by soft updates
to avoid deadlock when enlisting other processes to help with
the background cleanup. For the future it will allow the use of
shared locks for read access to vnodes. This change touches a
lot of files as it affects most filesystems within the system.
It has been well tested on FFS, loopback, and CD-ROM filesystems.
only lightly on the others, so if you find a problem there, please
let me (mckusick@mckusick.com) know.
pmap_qremove. pmap_kenter is not safe to use in MI code because it is not
guaranteed to flush the mapping from the tlb on all cpus. If the process
in question is preempted and migrates cpus between the call to pmap_kenter
and pmap_kremove, the original cpu will be left with stale mappings in its
tlb. This is currently not a problem for i386 because we do not use PG_G on
SMP, and thus all mappings are flushed from the tlb on context switches, not
just user mappings. This is not the case on all architectures, and if PG_G
is to be used with SMP on i386 it will be a problem. This was committed by
peter earlier as part of his fine grained tlb shootdown work for i386, which
was backed out for other reasons.
Reviewed by: peter
