If the sysctl variable is set to a value larger than TCP_MAXRXTSHIFT+1,
the array tcp_syn_backoff[] is accessed out of bounds.
Discussed with: jtl@
MFC after: 3 days
Sponsored by: Netflix, Inc.
Fields owned by the generic code were being left uninitialized,
causing problems in clear_dumper() if an error occurred.
Coverity CID: 1391200
X-MFC with: r333283
Per vnet(9), CURVNET_SET and CURVNET_RESTORE cannot be used as a single
statement for a conditional and CURVNET_RESTORE must be in the same
block as CURVNET_SET (or a subblock).
Reviewed by: andrew
Sponsored by: The FreeBSD Foundation
in_pcbfree will remove the incpb from the list and release the rtentry
while the vnet is set, but the actual destruction will be deferred
until any threads in a (not yet used) epoch section, no longer potentially
have references.
Avoid the ugly unlock / lock of the inpcbinfo where we need to
figure out what kind of lock we hold by simply deferring the
operation to another context. (Also a small dependency for
converting the pcbinfo read lock to epoch)
We need to set the current vnet before iterating over the global
interface list. Because the dump device may only be set from the host,
only proceed with configuration if the thread belongs to the default
vnet. [1]
Also fix a resource leak that occurs if the priv_check() in set_dumper()
fails.
Reported by: mmacy, sbruno [1]
Reviewed by: sbruno
X-MFC with: r333283
Differential Revision: https://reviews.freebsd.org/D15449
Each TCP connection that uses the system default cc_newreno(4) congestion
control algorithm module leaks a "struct newreno" (8 bytes of memory) at
connection initialisation time. The NULL-pointer dereference is only germane
when using the ABE feature, which is disabled by default.
While at it:
- Defer the allocation of memory until it is actually needed given that ABE is
optional and disabled by default.
- Document the ENOMEM errno in getsockopt(2)/setsockopt(2).
- Document ENOMEM and ENOBUFS in tcp(4) as being synonymous given that they are
used interchangeably throughout the code.
- Fix a few other nits also accidentally omitted from the original patch.
Reported by: Harsh Jain on freebsd-net@
Tested by: tjh@
Differential Revision: https://reviews.freebsd.org/D15358
If ifma_protospec is NULL when inm_lookup() is called, there
is a dereference in a NULL struct pointer. This ensures that struct is
not NULL before comparing the address.
Reported by: dumbbell
Reviewed by: sbruno
Sponsored by: Limelight Networks
Differential Revision: https://reviews.freebsd.org/D15440
The length of SCTP packets is always a multiple of 4. Therefore,
ensure that the MTUs used are also a multiple of 4.
Thanks to Irene Ruengeler for providing an earlier version of this
patch.
MFC after: 1 week
r333175 updated the join_group functions, but not the leave_group ones.
Reviewed by: sbruno
Sponsored by: Limelight Networks
Differential Revision: https://reviews.freebsd.org/D15393
Use full copyright year.
Remove 'All Rights Reserved' from new file (rights holder OK'd)
Minor #ifdef motion and #endif tagging
Remove __FBSDID macro from comments
Sponsored by: Netflix
OK'd by: rrs@
TCP's smoothed RTT (SRTT) can be much larger than an actual observed RTT. This can be either because of hz restricting the calculable RTT to 10ms in VMs or 1ms using the default 1000hz or simply because SRTT recently incorporated a larger value.
If an ACK arrives before the calculated badrxtwin (now + SRTT):
tp->t_badrxtwin = ticks + (tp->t_srtt >> (TCP_RTT_SHIFT + 1));
We'll erroneously reset snd_una to snd_max. If multiple segments were dropped and this happens repeatedly the transmit rate will be limited to 1MSS per RTO until we've retransmitted all drops.
Reported by: rstone
Reviewed by: hiren, transport
Approved by: sbruno
MFC after: 1 month
Differential Revision: https://reviews.freebsd.org/D8556
Currently when net.inet.carp.allow=0 CARP state remains as MASTER, which is
not very useful (if there are other masters -- it can lead to split brain,
if there are none -- it makes no sense). Having it as INIT makes it clear
that carp packets are disabled.
Submitted by: wg
MFC after: 1 month
Relnotes: yes
Sponsored by: iXsystems, Inc.
Differential Revision: https://reviews.freebsd.org/D14477
to sleep on commands to the NIC when updating multicast filters. More generally this permitted
driver's to use an sx as a softc lock. Unfortunately this change introduced a race whereby a
a multicast update would still be queued for deletion when ifconfig deleted the interface
thus calling down in to _purgemaddrs and synchronously deleting _all_ of the multicast addresses
on the interface.
Synchronously remove all external references to a multicast address before enqueueing for delete.
Reported by: lwhsu
Approved by: sbruno
This is a component of a system which lets the kernel dump core to
a remote host after a panic, rather than to a local storage device.
The server component is available in the ports tree. netdump is
particularly useful on diskless systems.
The netdump(4) man page contains some details describing the protocol.
Support for configuring netdump will be added to dumpon(8) in a future
commit. To use netdump, the kernel must have been compiled with the
NETDUMP option.
The initial revision of netdump was written by Darrell Anderson and
was integrated into Sandvine's OS, from which this version was derived.
Reviewed by: bdrewery, cem (earlier versions), julian, sbruno
MFC after: 1 month
X-MFC note: use a spare field in struct ifnet
Sponsored by: Dell EMC Isilon
Differential Revision: https://reviews.freebsd.org/D15253
to avoid a LOR on the multicast list lock in the freemoptions routines.
As it turns out, tcp_usr_detach can acquire the tcbinfo lock readonly.
Trying to wunlock the pcbinfo lock in that context has caused a number
of reported crashes.
This change unclutters in_pcbfree and moves the handling of wunlock vs
runlock of pcbinfo to the freemoptions routine.
Reported by: mjg@, bde@, o.hartmann at walstatt.org
Approved by: sbruno
In r309610 and r315514 the behavior of handling EACCES was changed, and
tcp_output() now returns zero when EACCES happens. The reason of this
change was a hesitation that applications that use TCP-MD5 will be
affected by changes in project/ipsec.
TCP-MD5 code returns EACCES when security assocition for given connection
is not configured. But the same error code can return pfil(9), and this
change has affected connections blocked by pfil(9). E.g. application
doesn't return immediately when SYN segment is blocked, instead it waits
when several tries will be failed.
Actually, for TCP-MD5 application it doesn't matter will it get EACCES
after first SYN, or after several tries. Security associtions must be
configured before initiating TCP connection.
I left the EACCES in the switch() to show that it has special handling.
Reported by: Andreas Longwitz <longwitz at incore dot de>
MFC after: 10 days
Multicast incorrectly calls in to drivers with a mutex held causing drivers
to have to go through all manner of contortions to use a non sleepable lock.
Serialize multicast updates instead.
Submitted by: mmacy <mmacy@mattmacy.io>
Reviewed by: shurd, sbruno
Sponsored by: Limelight Networks
Differential Revision: https://reviews.freebsd.org/D14969
they are more in order of cache line use as one passes
through the tcp_input/output paths (non-errors most likely path). This
helps speed up cache line optimization so that the tcp stack runs
a bit more efficently.
Sponsored by: Netflix Inc.
Differential Revision: https://reviews.freebsd.org/D15136
