Close a race with caching of -ve name lookups in the NFS client.
Specifically, clients only trust -ve cache entries while the directory
remains unchanged and discard any -ve cache entries for a directory when
they notice that the modification time of a directory entry changes. The
race involves two concurrent lookups as follows:
- Thread A does a lookup for file 'foo' which sends a lookup RPC to the
server. The lookup fails and the server replies.
- The 'foo' file is created (either by the same client or a different
client) updating the modification time on the parent directory of 'foo'.
- Thread B does a lookup for a different file 'bar' which updates the
cached attributes of the parent directory of 'foo' to reflect the new
modification time after 'foo' was created.
- Thread A finally resumes execution to parse the reply from the NFS
server. It adds a -ve cache entry and sets the cached value of the
directory's modification time that is used for invalidating -ve cached
lookups to the new modification time set by thread B.
At this point, future lookups of 'foo' will honor the -ve cached entry
until the cached entry is pushed out of the name cache's LRU or the
modification time of the parent directory is changed again by some other
change. The fix is to read the directory's modification time before
sending the lookup RPC and use that cached modification time when setting
the directory's cached modification time. Also, we do not add a -ve cache
entry if another thread has added -ve cache entry that set the directory's
cached modification time to a newer value than the value we read before
sending the lookup RPC.
Approved by: re (kib)
Make dhclient use bootpc (68) as the source port for unicast
DHCPREQUEST packets instead of allowing the protocol stack to pick
a random source port.
This fixes the behaviour where dhclient would never transition
from RENEWING to BOUND without going through REBINDING in networks
which are paranoid about DHCP spoofing, such as most mainstream
cable-broadband ISP networks.
Obtained from: OpenBSD
Reviewed by: brooks
Approved by: re (kib)
The flow-table function flowtable_route_flush() may be called
during system initialization time. Since the flow-table is
designed to maintain per CPU flow cache, the existing code
did not check whether "smp_started" is true before calling
sched_bind() and sched_unbind(), which triggers a page fault.
Reviewed by: jeff
Approved by: re
Powercrypt and NetSec seem to be defunct (webpages point to link farms
and a google search yields no alternative). Remove the links but
keep the entries around for reference.
Approved by: re (kib)
Change from CAM_TID_INVALID to CAM_SEL_TIMEOUT error code when the usb device
has been yanked, this works around a cam recounting bug when
CAM_DEV_UNCONFIGURED is set late in the detach. In certain conditions the
reference to the XPT device would not be released which would cause the usb
explore thread to sleep forever on "simfree", preventing any new usb devices to
be found/ejected on the bus.
Approved by: re (kib)
Remove spurious call to priv_check(PRIV_VM_SWAP_NOQUOTA).
Call priv_check(PRIV_VM_SWAP_NORLIMIT) only when per-uid limit is
actually exceed.
Approved by: re (kensmith)
In the ARP callout timer expiration function, the current time_second
is compared against the entry expiration time value (that was set based
on time_second) to check if the current time is larger than the set
expiration time. Due to the +/- timer granularity value, the comparison
returns false, causing the alternative code to be executed. The
alternative code path freed the memory without removing that entry
from the table list, causing a use-after-free bug.
Reviewed by: discussed with kmacy
Approved by: re
Verified by: rnoland, yongari
Make libc.a provide __stack_chk_fail_local weak alias. This is
needed to satisfy static libraries that are compiled with -fpic
and linked into static binary afterwards. Several libraries in
gcc are examples of such static libs.
Approved by: re (kib)
fixes a TX hang bug that it could happen when if_start callback didn't
be restarted by full of the output queue.
Tested by: bsduser <bsd at acd.homelinux.org>
MFC r198099:
fixes a TX hang that could be possible to happen when the trasfers are
in the high speed that some drivers don't call if_start callback after
marking ~IFF_DRV_OACTIVE.
Approved by: re (kib)
This patch fixes the following issues in the ARP operation:
1. There is a regression issue in the ARP code. The incomplete
ARP entry was timing out too quickly (1 second timeout), as
such, a new entry is created each time arpresolve() is called.
Therefore the maximum attempts made is always 1. Consequently
the error code returned to the application is always 0.
2. Set the expiration of each incomplete entry to a 20-second
lifetime.
3. Return "incomplete" entries to the application.
4. The return error code was incorrect.
Reviewed by: kmacy
Approved by: re
of problems on non-DELL branded machines with IPMI
support. The proposed fix was committed to HEAD but has
not received much test coverage yet.
Discussed with: bz
Approved by: re (kensmith)
Map PIE binaries at non-zero base address.
MFC r198202:
Honour non-zero mapbase for PIE binaries. Inform interpreter-less PIE
binary about its relocbase.
Approved by: re (kensmith)
Define architectural load bases for PIE binaries.
MFC r198203 (by marius):
Change load base for sparc to match default gcc memory layout model.
Approved by: re (kensmith)
Use zfs_read() instead of xfsread() to read /boot.config. xfsread() fails
short read requests, so the result was that a /boot.config smaller than 512
bytes was ignored. boot2 uses fsread() instead of xfsread() to read
/boot.config already, so this makes zfsboot more like boot2.
Approved by: re (kib)
Print routing statistics as unsigned short rather than unsigned int,
otherwise sign extension leads to unlikely values when in the negative
range of the signed short structure fields that hold the statistics.
The type used to hold routing statistics is arguably also incorrect.
Approved by: re (bz)
Link GSS mechanics modules against libgssapi so they will not fail due
unresolved symbol errors when in turn libgssapi was loaded with RTLD_LOCAL
flag set (which is the default).
Approved by: re (kib)
In regards to the "Starting foo:" type messages at boot time, create
and employ a more generic solution, and use it in the individual rc.d
scripts that also have an $rc_quiet test:
1. Add check_startmsgs() to rc.subr.
2. In the rc.d scripts that use rc_quiet (and rc.subr) substitute
variations of [ -z "$rc_quiet" ] with check_startmsgs
3. In savecore add a trailing '.' to the end of the message to make it
more consistent with other scripts.
4. In newsyslog remove a : before the terminal '.' since we do not
expect there to be anything printed out in between to make it more
consistent.
5. In the following scripts change "quotes" to 'quotes' where no
variables exist in the message: savecore pf newsyslog
6. [Does not apply in RELENG_8]
7. In the following scripts separate the "Starting foo:" from the
terminal '.' to make them more consistent: moused hostname pf
8. In nfsclient move the message to its own line to avoid a style bug
9. In pf rc_quiet does not apply to the _stop method, so remove the
test there.
10. In motd add 'quotes' around the terminal '.' for consistency
Approved by: re (kib)
Change the default transport protocol for use by the Mount protocol
and the NFS Null RPC done by mount_nfs from UDP to TCP, so that it is
consistent with the kernel, which already uses NFS over TCP by
default. Without this change, doing an NFS mount
against a server that only supports UDP results in an unusable
mount point if a transport protocol option wasn't specified for the
mount.
Approved by: re (kib)
In nanosleep(2), note that the calling thread is put to sleep, not the
whole process. Also explicitely name the parameter that specifies
sleep interval.
Approved by: re (kensmith)
Fix the typo mentioned in the PR, and one additional.
Fix caps while I'm here.
PR: conf/138087
Submitted by: Chris Petrik <c.petrik.sosa@gmail.com>
Approved by: re (kib)
In function do_rw_wrlock, when a writer got an error and before returning,
check if there are readers blocked by us via URWLOCK_WRITE_WAITERS flag,
and resume the readers. The error must be EAGAIN, otherwise there must
have memory problem, and nobody can rescue the buggy application.
Approved by: re (kib), davidxu
Refine r195509, instead of checking that vnode type is VBAD, that is
set quite late in the revocation path, properly verify that vnode is
not doomed before calling VOP.
Approved by: re (bz)
If provider is open for writing when we taste it, skip it for classes that
depend on on-disk metadata. This was we won't attach to providers that are used
by other classes. For example we don't want to configure partitions on da0 if
it is part of gmirror, what we really want is partitions on mirror/foo.
During regular work it works like this: if provider is open for writing a class
receives the spoiled event from GEOM and detaches, once provider is closed the
taste event is send again and class can rediscover its metadata if it is still
there. This doesn't work that way when new class arrives, because GEOM gives
all existing providers for it to taste, also those open for writing. Classes
have to decided on their own if they want to deal with such providers (eg.
geom_dev) or not (classes modified by this commit).
Reported by: des, Oliver Lehmann <lehmann@ans-netz.de>
Tested by: des, Oliver Lehmann <lehmann@ans-netz.de>
Discussed with: phk, marcel
Reviewed by: marcel
Approved by: re (kib)
r197831:
Fix situation where Mac OS X NFS client creates a file and when it tries
to set ownership and mode in the same setattr operation, the mode was
overwritten by secpolicy_vnode_setattr().
PR: kern/118320
Submitted by: Mark Thompson <info-gentoo@mark.thompson.bz>
r197842:
Fix white-spaces.
r197843:
On FreeBSD it is enough to report provider removal when orphan event is
received, we don't have to do it on every ENXIO error in I/O path.
Solaris has no GEOM so they have to handle it in a less clean way.
r197860:
File system owner is when uid matches and jail matches.
r197861:
Allow file system owner to modify system flags if securelevel permits.
Approved by: re (kib)
Per their definition, atomic instructions used in conjuction with
memory barriers should also ensure that the compiler doesn't reorder paths
where they are used. GCC, however, does that aggressively, even in
presence of volatile operands. The most reliable way GCC offers for avoid
instructions reordering is clobbering "memory".
Not all our memory barriers, right now, clobber memory for GCC-like
compilers.
Fix these cases.
Approved by: re (kib)
Fix tcsh losing history when tcsh terminates because the pty beneath it
is closed.
Diagnosed by Ted Anderson:
New signal queuing logic was introduced in 6.15 and allows the signal handlers
to be run explicitly by calling handle_pending_signals, instead of
immediately when the signal is delivered. This function is called at
various places, typically when receiving a EINTR from a slow system call
such as read or write. In the pty exit case, it was called from xwrite,
called from flush, while printing the "exit" message after receiving EOF
when reading from the pty (note that the read did not return EINTR but
zero bytes, indicating EOF). The SIGHUP handler, phup(), called
rechist, which opened the history file and began writing the merged
history to it. This process invoked flush recursively to actually write
the data. In this case, however, the flush noticed it was being called
recursively and decided fail by calling stderror.
My conclusion was that the signal was being handled at a bad time. But
whether to fix flush not to care about the recursive call, or to handle
the signal some other time and when to handle it, was unclear to me.
However, by adding an extra call to handle_pending_signals, just after
process() returns to main(), I was able to avoid the truncated history
after network outages and similar failures. I verified this fix in
version 6.17.
Approved by: re (kib)
When releasing a read/shared lock we need to use a write memory barrier
in order to avoid, on architectures which doesn't have strong ordered
writes, CPU instructions reordering.
Approved by: re (kib)
