suid application. The problem is that Linux applications using old Linux
threads (pre-NPTL) use signal 32 (linux SIGRTMIN) for communication between
thread-processes. If such an linux application is installed suid or sgid
and security.bsd.conservative_signals=1 (default), then permission will be
denied to send such a signal and the application will freeze.
I believe the same will be true for native applications that use libthr,
since libthr uses SIGTHR for implementing conditional variables.
PR: 72922
Submitted by: Andriy Gapon <avg@icyb.net.ua>
MFC after: 2 weeks
list, set `curr_callout' to NULL. This ensures that we won't attempt
to cancel the current callout if the original callout structure
gets recycled while we wait to acquire Giant.
This is reported to fix an intermittent syscons problem that was
introduced by revision 1.96.
do not need to perform an extra memory fetch in the Packet (Mbuf+Cluster)
constructor to initialize the reference counter anymore. The reference
counts are located in a separate memory region (in the slab header,
because this zone is UMA_ZONE_REFCNT), so the memory fetch resulted very
often in a cache miss. Additionally, and perhaps more significantly,
optimize the free mbuf+cluster (packet) case, which is very common, to
no longer require an atomic operation on free (to verify the reference
counter) if the reference on the cluster has never been increased (also
very common). Reduces an atomic on mbuf free on average.
Original patch submitted by: Gerrit Nagelhout <gnagelhout@sandvine.com>
behaviour of chflags within a jail. If set to 0 (the default), then a
jailed root user is treated as an unprivileged user; if set to 1, then
a jailed root user is treated the same as an unjailed root user.
This is necessary to allow "make installworld" to work inside a jail,
since it attempts to manipulate the system immutable flag on certain
files.
Discussed with: csjp, rwatson
MFC after: 2 weeks
Give FFS vnodes a specific bufwrite method which contains all the
background write stuff and then calls into the default bufwrite()
for the rest of the job.
Remove all the background write related stuff from the normal bufwrite.
This drags the softdep_move_dependencies() back into FFS.
Long term, it is worth looking at simply copying the data into
allocated memory and issuing the bio directly and not create the
"shadow buf" in the first place (just like copy-on-write is done
in snapshots for instance). I don't think we really gain anything
but complexity from doing this with a buf.
structure in the struct pointed to by the 3rd argument for IPC_STAT and
get rid of the 4th argument. The old way returned a pointer into the
kernel array that the calling function would then access afterwards
without holding the appropriate locks and doing non-lock-safe things like
copyout() with the data anyways. This change removes that unsafeness and
resulting race conditions as well as simplifying the interface.
- Implement kern_foo wrappers for stat(), lstat(), fstat(), statfs(),
fstatfs(), and fhstatfs(). Use these wrappers to cut out a lot of
code duplication for freebsd4 and netbsd compatability system calls.
- Add a new lookup function kern_alternate_path() that looks up a filename
under an alternate prefix and determines which filename should be used.
This is basically a more general version of linux_emul_convpath() that
can be shared by all the ABIs thus allowing for further reduction of
code duplication.
callout is first initialised, using a new function callout_init_mtx().
The callout system will acquire this mutex before calling the callout
function and release it on return.
In addition, the callout system uses the mutex to avoid most of the
complications and race conditions inherent in asynchronous timer
facilities, so mutex-protected callouts have much simpler semantics.
As long as the mutex is held when invoking callout_stop() or
callout_reset(), then these functions will guarantee that the callout
will be stopped, even if softclock() had already begun to process
the callout.
Existing Giant-locked callouts will automatically pick up the new
race-free semantics. This should close a number of race conditions
in the USB code and probably other areas of the kernel too.
There should be no change in behaviour for "MP-safe" callouts; these
still need to use the techniques mentioned in timeout(9) to avoid
race conditions.
frequency as a percentage of the base rate and do not change the base
rate directly. The cpufreq framework combines these with absolute drivers
to produce synthesized levels made of one or more settings.
select the CPU frequency level (say for cooling). The driver interface
allows hardware drivers to announce themselves as capable of adjusting
an individual frequency setting.
- Add buffer size limitations (overflow will not be possible anymore).
- Add 'visible' option, which will allow for passphrase reading in the
future.
- Remove special treatment of '@' and '#', those two are only confusing.
Discussed with: rwatson
MFC after: 2 weeks
tond and not fromnd. This could lead us to leak Giant, or unlock it
twice, depending on the filesystems involved. renames within a single
filesystem would not have caused any problems.
Sponsored by: Isilon Systems, Inc.
all reserved, as the lisence makes clear), and strike the third clause
(now this is a 2-clause liberal BSDL as are the rest of files I hold
copyright over).
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