between being commited to a machno and having acquired the lock, the
scheduler could come in an schedule us on a different processor. the
solution is to have dtmachlock() take a special -1 argument to mean
"current mach" and return the actual mach number after the lock has
been acquired and interrupts being disabled.
when /n/src9 is an alias for / (bind / /n/src9), then the bind
from /sys/lib/dist/usr on /n/src9/usr would also overbind
/usr and potentially make the build target file inaccessible.
the solution is to run aux/stub -d /n/src9/usr.
this works as aux/stub mounts itself on /n/src9, so the bind
for /n/src9/usr will not override /usr in the root filesystem
but the stub directory from aux/stub.
this fixes the miscompilation of 6l with 5c resulting in bogus
vlong -> long conversion at the top of asmandsz():
asmandsz 0x0000aec4 MOVW.W R14,#-0x2c(R13)
asmandsz+0x4 0x0000aec8 MOVW rex+8(FP),R5
asmandsz+0x8 0x0000aecc MOVW $andptr-SB(SB),R7
asmandsz+0xc 0x0000aed0 MOVW R0,R6
asmandsz+0x10 0x0000aed4 AND $#0x44,R5,R8
asmandsz+0x14 0x0000aed8 MOVW R8,rex+8(FP)
asmandsz+0x18 0x0000aedc MOVW R0,R4
asmandsz+0x1c 0x0000aee0 MOVM.IA (R0),[R1,R3] <- R1 used here
asmandsz+0x20 0x0000aee4 MOVW R8,v-4(SP) <- substituted by R8
- do not write /net/ndb for loopback medium unless -p is specified
- use defmask() instead of hardcoded /64 for v6 to get correct /128 mask for ::1
- only do duplicate address detection on ethernet
- increase buffer size to support up to 4096 bit RSA keys
- handle PMTUDiscovery option and respond to pmtu probes
- handle port in Address option
- wlock(&netlk) before closing udpfd to sync with writers
- move default subnet handling out of gethost()
using ~IP_DF mask to select offset and "more fragments" bits
includes the evil bit 15. so instead define a constant IP_FO
for the fragment offset bits and use (IP_MF|IP_FO). that way
the evil bit gets ignored and doesnt cause any useless calls
to ipreassemble().
tested on a t43 with igfx and a 1600x1200 t43p screen
what works: lvds, blanking
what doesn't: hwgc (not visible), snarfing edid
untested: vga
based on realemu traces.
only try listen/dial on udp when IndirectData/TcpOnly is not
enabled.
add support for scipts:
host-up
host-down
tinc-up
tinc-down
subnet-up
subnet-down
when dialing udp connection, only switch when there is no
other udp connection active. when we receive an authenticated
message, we switch to that connection immidiately.
unfraglen() had the side effect that it would always copy the
nexthdr field from the fragment header to the previous nexthdr
field. this is fine when we reassemble packets but breaks
fragments that we want to just forward unchanged.
given that we now keep the block size consistent with the
ip packet size, the variable header part of the ip packet
is just: BLEN(bp) - fp->flen == fp->hlen.
fix bug in ip6reassemble() in the non-fragmented case:
reload ih after ip header was moved before writing ih->ploadlen.
use concatbloc() instead of pullupblock().
some protocols assume that Ip4hdr.length[] and Ip6hdr.ploadlen[]
are valid and not out of range within the block but this has
not been verified. also, the ipv4 and ipv6 headers can have variable
length options, which was not considered in the fragmentation and
reassembly code.
to make this sane, ipiput4() and ipiput6() now verify that everything
is in range and trims to block to the expected size before it does
any further processing. now blocklen() and Ip4hdr.length[] are conistent.
ipoput4() and ipoput6() are simpler now, as they can rely on
blocklen() only, not having a special routing case.
ip fragmentation reassembly has to consider that fragments could
arrive with different ip header options, so we store the header+option
size in new Ipfrag.hlen field.
unfraglen() has to make sure not to run past the buffer, and hadle
the case when it encounters multiple fragment headers.
kivik wrote:
I've found a nasty bug in lib9p handling of Tversion
messages, where an invalid version string in the request
leads to servers abort()ing the spaceship.
To reproduce:
; ramfs -S ram
; aux/9pcon /srv/ram
Tversion ~0 DIE
The issue lies in sversion() where in case an invalid
version string is received we respond right away with
ofcall.version="unknown"; however, we fail to set the
ofcall.msize, which at this point is cleared to 0. This
causes the convS2M call in respond() to fail and abort being
called.
we want to accept V4 subnets in CIDR notation consistently which
means we need to interpret the mask in context of the IP address.
so parseipmask() now has an additional v4 flag argument which
offsets the prefixlength by 96 so a /24 will be interpreted
as a /120.
parseipandmask() is the new function which handles this automatically
depending on the ip address type.
v4parsecidr() is now obsolete.
steve wrote:
> I cam across a bug in cifs.
>
> An empty directory under windows 7 pro contains a single entry "." but it
> doesn't appear to contain "..". As a result "." is not removed on dirscan
> and plan9 gets when trying to traverse the hierarchy.
all screen implementations use a Memimage* internally
for the framebuffer, so we can return a shared reference
to its Memdata structure in attachscreen() instead of
a framebuffer data pointer.
this eleminates the softscreen == 0xa110c hack as we
always use shared Memdata* now.
Under the normal close sequence, when we receive a FIN|ACK, we enter
TIME-WAIT and respond to that LAST-ACK with an ACK. Our TCP stack would
send an ACK in response to *any* ACK, which included FIN|ACK but also
included regular ACKs. (Or PSH|ACKs, which is what we were actually
getting/sending).
That was more ACKs than is necessary and results in an endless ACK storm
if we were under the simultaneous close sequence. In that scenario,
both sides of a connection are in TIME-WAIT. Both sides receive
FIN|ACK, and both respond with an ACK. Then both sides receive *those*
ACKs, and respond again. This continues until the TIME-WAIT wait period
elapses and each side's TCP timers (in the Plan 9 / Akaros case) shut
down.
The fix for this is to only respond to a FIN|ACK when we are in TIME-WAIT.