changers that don't support the DVCID and CURDATA bits that were
introduced in the SMC spec.
These changers will return an Illegal Request type error if the
bits are set. This causes "chio status" to fail.
The fix is two-fold. First, for changers that claim to be SCSI-2
or older, don't set the DVCID and CURDATA bits for READ ELEMENT
STATUS. For newer changers (SCSI-3 and newer), we default to
setting the new bits, but back off and try the READ ELEMENT STATUS
without the bits if we get an Illegal Request type error.
This has been tested on a Qualstar TLS-8211, which is a SCSI-2
changer that does not support the new bits, and a Spectra T-380,
which is a SCSI-3 changer that does support the new bits. In the
absence of a SCSI-3 changer that does not support the bits, I
tested that with some error injection code. (The SMC spec says
that support for CURDATA is mandatory, and DVCID is optional.)
scsi_ch.c: Add a new quirk, CH_Q_NO_DVCID that gets set for
SCSI-2 and older libraries, or newer libraries that
report errors when the DVCID/CURDATA bits are set.
In chgetelemstatus(), use the new quirk to
determine whether or not to set DVCID and CURDATA.
If we get an error with the bits set, back off and
try without the bits. Set the quirk flag if the
read element status succeeds without the bits set.
Increase the READ ELEMENT STATUS timeout to 60
seconds after testing with a Spectra T-380. The
previous value was 10 seconds, and too short for
the T-380. This may be decreased later after
some additional testing and investigation.
Tested by: Andre Albsmeier <Andre.Albsmeier@siemens.com>
Sponsored by: Spectra Logic
MFC after: 3 days
Although using -i with -c does not seem very useful, it seems inappropriate
to read commands from the terminal in this case.
Side effect: if the -s -c extension is used and the -s option is turned off
using 'set +s' during the interactive part, the shell now exits after an
error or interrupt. Note that POSIX only specifies -s as option to sh, not
to set.
See also Austin Group issue #718.
Submitted by: "YAMAMOTO, Shigeru" <shigeru@iij.ad.jp>
Reviewed by: adrian
In PC-BSD 9.1, VIMAGE is enabled in the kernel config.
For laptops with Bluetooth capability, such as the HP Elitebook 8460p,
the kernel will panic upon bootup, because curthread->td_vnet
is not initialized.
Properly initialize curthread->td_vnet when initializing the Bluetooth stack.
This allows laptops such as the HP Elitebook 8460p laptop
to properly boot with VIMAGE kernels.
them changed (or was removed from the tree) then portsnap would delete
that file. This happened earlier today when one of two empty port
directories was removed. Uniquifying the lists of needed files fixes
this.
9.2-RELEASE candidate.
MFC after: 3 days
to drain the reserve. This was broken in r243040, causing deadlock.
Note that VM_WAIT call in case of uma_zalloc() failure from pagedaemon
would only wait for the v_pageout_free_min anyway.
Reported and tested by: pho
Reviewed by: alc
Sponsored by: The FreeBSD Foundation
information into the ISN (initial sequence number) without the additional
use of timestamp bits and switching to the very fast and cryptographically
strong SipHash-2-4 MAC hash algorithm to protect the SYN cookie against
forgeries.
The purpose of SYN cookies is to encode all necessary session state in
the 32 bits of our initial sequence number to avoid storing any information
locally in memory. This is especially important when under heavy spoofed
SYN attacks where we would either run out of memory or the syncache would
fill with bogus connection attempts swamping out legitimate connections.
The original SYN cookies method only stored an indexed MSS values in the
cookie. This isn't sufficient anymore and breaks down in the presence of
WSCALE information which is only exchanged during SYN and SYN-ACK. If we
can't keep track of it then we may severely underestimate the available
send or receive window. This is compounded with large windows whose size
information on the TCP segment header is even lower numerically. A number
of years back SYN cookies were extended to store the additional state in
the TCP timestamp fields, if available on a connection. While timestamps
are common among the BSD, Linux and other *nix systems Windows never enabled
them by default and thus are not present for the vast majority of clients
seen on the Internet.
The common parameters used on TCP sessions have changed quite a bit since
SYN cookies very invented some 17 years ago. Today we have a lot more
bandwidth available making the use window scaling almost mandatory. Also
SACK has become standard making recovering from packet loss much more
efficient.
This change moves all necessary information into the ISS removing the need
for timestamps. Both the MSS (16 bits) and send WSCALE (4 bits) are stored
in 3 bit indexed form together with a single bit for SACK. While this is
significantly less than the original range, it is sufficient to encode all
common values with minimal rounding.
The MSS depends on the MTU of the path and with the dominance of ethernet
the main value seen is around 1460 bytes. Encapsulations for DSL lines
and some other overheads reduce it by a few more bytes for many connections
seen. Rounding down to the next lower value in some cases isn't a problem
as we send only slightly more packets for the same amount of data.
The send WSCALE index is bit more tricky as rounding down under-estimates
the available send space available towards the remote host, however a small
number values dominate and are carefully selected again.
The receive WSCALE isn't encoded at all but recalculated based on the local
receive socket buffer size when a valid SYN cookie returns. A listen socket
buffer size is unlikely to change while active.
The index values for MSS and WSCALE are selected for minimal rounding errors
based on large traffic surveys. These values have to be periodically
validated against newer traffic surveys adjusting the arrays tcp_sc_msstab[]
and tcp_sc_wstab[] if necessary.
In addition the hash MAC to protect the SYN cookies is changed from MD5
to SipHash-2-4, a much faster and cryptographically secure algorithm.
Reviewed by: dwmalone
Tested by: Fabian Keil <fk@fabiankeil.de>
hash function) optimized for speed on short messages returning a 64bit hash/
digest value.
SipHash is simpler and much faster than other secure MACs and competitive
in speed with popular non-cryptographic hash functions. It uses a 128-bit
key without the hidden cost of a key expansion step. SipHash iterates a
simple round function consisting of four additions, four xors, and six
rotations, interleaved with xors of message blocks for a pre-defined number
of compression and finalization rounds. The absence of secret load/store
addresses or secret branch conditions avoid timing attacks. No state is
shared between messages. Hashing is deterministic and doesn't use nonces.
It is not susceptible to length extension attacks.
Target applications include network traffic authentication, message
authentication (MAC) and hash-tables protection against hash-flooding
denial-of-service attacks.
The number of update/finalization rounds is defined during initialization:
SipHash24_Init() for the fast and reasonable strong version.
SipHash48_Init() for the strong version (half as fast).
SipHash usage is similar to other hash functions:
struct SIPHASH_CTX ctx;
char *k = "16bytes long key"
char *s = "string";
uint64_t h = 0;
SipHash24_Init(&ctx);
SipHash_SetKey(&ctx, k);
SipHash_Update(&ctx, s, strlen(s));
SipHash_Final(&h, &ctx); /* or */
h = SipHash_End(&ctx); /* or */
h = SipHash24(&ctx, k, s, strlen(s));
It was designed by Jean-Philippe Aumasson and Daniel J. Bernstein and
is described in the paper "SipHash: a fast short-input PRF", 2012.09.18:
https://131002.net/siphash/siphash.pdf
Permanent ID: b9a943a805fbfc6fde808af9fc0ecdfa
Implemented by: andre (based on the paper)
Reviewed by: cperciva
is being wired now. The entry wired count is changed to non-zero in
advance, before the map lock is dropped. This makes the vm_fault() to
perceive the entry as wired, and breaks the fragment which moves the
wire count from the shadowed page, to the upper page, making the code
unwiring non-wired page.
On the other hand, the vm_fault() calls from vm_fault_wire() should be
allowed to proceed, so only drain MAP_ENTRY_IN_TRANSITION from
vm_fault() when wiring_thread is not current.
Reported and tested by: pho
Reviewed by: alc
Sponsored by: The FreeBSD Foundation
MFC after: 2 weeks
parallel creation of the map entries, e.g. by mmap() or stack growing.
It also breaks when other entry is wired in parallel.
The vm_map_wire() iterates over the map entries in the region, and
assumes that map entries it finds are marked as in transition before,
also that any entry marked as in transition, are marked by the current
invocation of vm_map_wire(). This is not true for new entries in the
holes.
Add the thread owner of the MAP_ENTRY_IN_TRANSITION flag to struct
vm_map_entry. In vm_map_wire() and vm_map_unwire(), only process the
entries which transition owner is the current thread.
Reported and tested by: pho
Reviewed by: alc
Sponsored by: The FreeBSD Foundation
MFC after: 2 weeks
msync(MS_INVALIDATE). The vm_fault_copy_entry() requires that object
range which corresponds to the user-wired vm_map_entry, is always
fully populated.
Add OBJPR_NOTWIRED flag for vm_object_page_remove() to request the
preserving behaviour, use it when calling vm_object_page_remove() from
vm_object_sync().
Reported and tested by: pho
Reviewed by: alc
Sponsored by: The FreeBSD Foundation
MFC after: 2 weeks
not busy, since its only caller brelse() can legitimately call it on
busy page. This happens for VOP_PUTPAGES() on filesystems that use
buffers and which VOP_WRITE() method marked the buffer containing page
as non-cacheable.
Reported and tested by: pho
Reviewed by: alc
Sponsored by: The FreeBSD Foundation
MFC after: 2 weeks
error if any user wired mappings exist. Doing the invalidation
destroys the user wiring.
The change is the temporal measure to close the bug, the more proper
fix is to delegate the invalidation of the page to upper layers
always.
Reported and tested by: pho
Reviewed by: alc
Sponsored by: The FreeBSD Foundation
MFC after: 2 weeks
processing. Thanks for John Baldwin for catching this. Not
clearing the flag member of the rxbuf could result in a NULL
mbuf pointer being used.
MFC after: 2 days (this needs to get into 9.2!)
an executable by-name without forking or using externals.
In a performance benchmark of 10,000 runs on circa 2006 hardware, f_which
out-performed `which' with an average completion time of ~2.5 seconds versus
~56 seconds.
This should be handy for future use (not that I make it a habit to call
`which' in a loop 10,000 times).
isdir? ( fd -- bool )
freaddir ( fd -- ptr len TRUE | FALSE )
The 'isdir?' word returns `true' if the file descriptor is for a
directory and `false' otherwise.
The 'freaddir' word reads the next directory entry and if successful,
returns its name and 'true'. Otherwise 'false' is returned.
These words give the loader the ability to scan directories and read
files contained in them for 'rc.d'-like flexibility in handling which
modules to load and/or which tunables to set.
Obtained from: Juniper Networks, Inc.
kvm_uread() function, used for reading from /proc/pid/mem, was
removed too. But the function declaration remained in kvm.h
public header and the soname was not bumped.
Remove kvm_uread() from kvm.h and bump the soname.
Reported by: rmh
Discussed on: arch
