incoming ARP packet and route request adding/removing
ARP entries. The root of the problem is that
struct llinfo_arp was accessed without any locks.
To close race we will use locking provided by
rtentry, that references this llinfo_arp:
- Make arplookup() return a locked rtentry.
- In arpresolve() hold the lock provided by
rt_check()/arplookup() until the end of function,
covering all accesses to the rtentry itself and
llinfo_arp it refers to.
- In in_arpinput() do not drop lock provided by
arplookup() during first part of the function.
- Simplify logic in the first part of in_arpinput(),
removing one level of indentation.
- In the second part of in_arpinput() hold rtentry
lock while copying address.
o Fix a condition when route entry is destroyed, while
another thread is contested on its lock:
- When storing a pointer to rtentry in llinfo_arp list,
always add a reference to this rtentry, to prevent
rtentry being destroyed via RTM_DELETE request.
- Remove this reference when removing entry from
llinfo_arp list.
o Further cleanup of arptimer():
- Inline arptfree() into arptimer().
- Use official queue(3) way to pass LIST.
- Hold rtentry lock while reading its structure.
- Do not check that sdl_family is AF_LINK, but
assert this.
Reviewed by: sam
Stress test: http://www.holm.cc/stress/log/cons141.html
Stress test: http://people.freebsd.org/~pho/stress/log/cons144.html
- rt0 passed to rt_check() must not be NULL, assert this.
- rt returned by rt_check() must be valid locked rtentry,
if no error occured.
o Modify callers, so that they never pass NULL rt0
to rt_check().
Reviewed by: sam, ume (nd6.c)
#if 0.
- Use pci_enable_busmaster() to enable busmastering instead of frobbing
the command register directly.
- Don't check to see if memory or I/O can be enabled by writing to the
command register. The PCI bus driver's bus_alloc_resource() method
already checks this and will fail if it can't enable the bit.
everywhere. This means that my_unit is no longer used as well. The
watchdog routine now also prints 'my0: ...' rather than 'm0x0: ...'.
- Don't bzero the softc and don't try to free it in detach or if attach
fails.
- A whitespace fix.
- Use the driver lock instead of Giant in a bus dma callback.
- Clear IFF_DRV_(RUNNING|OACTIVE) in hme_stop() instead of just clearing
RUNNING in hme_ioctl() to be more like other ethernet drivers.
- Lock the driver lock around mii operations.
- Remove spls.
- Cleanup locking in hme_ioctl().
MFC after: 1 week
use the station channel properties. Fixes assert failure/bogus
operation when an ap is operating in 11a and has associated stations
then switches to 11g.
Noticed by: Michal Mertl
Reviewed by: avatar
MFC after: 2 weeks
o add ic_curchan and use it uniformly for specifying the current
channel instead of overloading ic->ic_bss->ni_chan (or in some
drivers ic_ibss_chan)
o add ieee80211_scanparams structure to encapsulate scanning-related
state captured for rx frames
o move rx beacon+probe response frame handling into separate routines
o change beacon+probe response handling to treat the scan table
more like a scan cache--look for an existing entry before adding
a new one; this combined with ic_curchan use corrects handling of
stations that were previously found at a different channel
o move adhoc neighbor discovery by beacon+probe response frames to
a new ieee80211_add_neighbor routine
Reviewed by: avatar
Tested by: avatar, Michal Mertl
MFC after: 2 weeks
due to the vm object being locked.
When a process writes large amounts of data to a file, the vm object associated
with that file can contain most of the physical pages on the machine. If the
process is preempted while holding the lock on the vm object, pagedaemon would
be able to move very few pages from PQ_INACTIVE to PQ_CACHE or from PQ_ACTIVE
to PQ_INACTIVE, resulting in unlimited cleaning of dirty pages belonging to
other vm objects.
Temporarily unlock the page queues lock while locking vm objects to avoid lock
order violation. Detect and handle relevant page queue changes.
This change depends on both the lock portion of struct vm_object and normal
struct vm_page being type stable.
Reviewed by: alc
to atomically return either an existing set of IP multicast options for the
PCB, or a newlly allocated set with default values. The inpcb is returned
locked. This function may sleep.
Call ip_moptions() to acquire a reference to a PCB's socket options, and
perform the update of the options while holding the PCB lock. Release the
lock before returning.
Remove garbage collection of multicast options when values return to the
default, as this complicates locking substantially. Most applications
allocate a socket either to be multicast, or not, and don't tend to keep
around sockets that have previously been used for multicast, then used for
unicast.
This closes a number of race conditions involving multiple threads or
processes modifying the IP multicast state of a socket simultaenously.
MFC after: 7 days
list lock, as there has been a report that an alternative lock order
is getting introduced. This should help ferret it out.
Reported by: Ed Maste <emaste at phaedrus dot sandvine dot ca>
device driver, owned by the network stack, or initialized by the device
driver before attach and read-only from then on.
Not all device drivers and network stack components currently follow
these rules, especially with respect to IFF_UP, and a few exceptions
with IFF_ALLMULTI.
MFC after: 7 days
IFF_DRV_RUNNING, as well as the move from ifnet.if_flags to
ifnet.if_drv_flags. Device drivers are now responsible for
synchronizing access to these flags, as they are in if_drv_flags. This
helps prevent races between the network stack and device driver in
maintaining the interface flags field.
Many __FreeBSD__ and __FreeBSD_version checks maintained and continued;
some less so.
Reviewed by: pjd, bz
MFC after: 7 days
and move both flags from ifnet.if_flags to ifnet.if_drv_flags, making
and documenting the locking of these flags the responsibility of the
device driver, not the network stack. The flags for these two fields
will be mutually exclusive so that they can be exposed to user space as
though they were stored in the same variable.
Provide #defines to provide the old names #ifndef _KERNEL, so that user
applications (such as ifconfig) can use the old flag names. Using the
old names in a device driver will result in a compile error in order to
help device driver writers adopt the new model.
When exposing the interface flags to user space, via interface ioctls
or routing sockets, or the two fields together. Since the driver flags
cannot currently be set for user space, no new logic is currently
required to handle this case.
Add some assertions that general purpose network stack routines, such
as if_setflags(), are not improperly used on driver-owned flags.
With this change, a large number of very minor network stack races are
closed, subject to correct device driver locking. Most were likely
never triggered.
Driver sweep to follow; many thanks to pjd and bz for the line-by-line
review they gave this patch.
Reviewed by: pjd, bz
MFC after: 7 days
- Push 'i' into the only block where it is used.
- Remove redundant check for rt being NULL. If rt_check() hasn't
returned an error, then rt is valid.
Reviewed by: gnn
m_copym(m, 0, M_COPYALL, how).
This is required for strict alignment architectures where we align the IP
header in the input path but m_copym() will create an unaligned copy in
bridge_broadcast(). m_copypacket() preserves alignment of the first mbuf.
Noticed by: Petri Simolin
Approved by: mlaier (mentor)
MFC after: 3 days
not holding any non-sleep-able-locks locks when copyin is called.
This gets executed un-conditionally since we have no function
to wire the buffer in this direction.
Pointed out by: truckman
MFC after: 1 week
the timeout routine.
- Fix locking in detach.
- Add locking in shutdown.
- Don't mess with the PCI command register in resume, the PCI bus driver
already does this for us.
- Add locking to the non-serial ifmedia routines.
- Fix locking in ioctl.
- Remove spls and support for 4.x.
MFC after: 1 week
event handler, dev_clone, which accepts a credential argument.
Implementors of the event can ignore it if they're not interested,
and most do. This avoids having multiple event handler types and
fall-back/precedence logic in devfs.
This changes the kernel API for /dev cloning, and may affect third
party packages containg cloning kernel modules.
Requested by: phk
MFC after: 3 days
I copied strcasecmp() from userland to the kernel and it didn't worked!
I started to debug the problem and I find out that this line:
while (tolower(*us1) == tolower(*us2++)) {
was adding _3_ bytes to 'us2' pointer. Am I loosing my minds here?!...
No, in-kernel tolower() is a macro which uses its argument three times.
Bad tolower(9), no cookie.
the buffer has not been wired and we are holding any non-sleep-able locks,
drop a witness warning. If the buffer has not been wired, it is possible
that the writing of the data can sleep, especially if the page is not in
memory. This can result in a number of different locking issues, including
dead locks.
MFC after: 1 week
Discussed with: rwatson
Reviewed by: jhb
Crypto changes:
o change driver/net80211 key_alloc api to return tx+rx key indices; a
driver can leave the rx key index set to IEEE80211_KEYIX_NONE or set
it to be the same as the tx key index (the former disables use of
the key index in building the keyix->node mapping table and is the
default setup for naive drivers by null_key_alloc)
o add cs_max_keyid to crypto state to specify the max h/w key index a
driver will return; this is used to allocate the key index mapping
table and to bounds check table loookups
o while here introduce ieee80211_keyix (finally) for the type of a h/w
key index
o change crypto notifiers for rx failures to pass the rx key index up
as appropriate (michael failure, replay, etc.)
Node table changes:
o optionally allocate a h/w key index to node mapping table for the
station table using the max key index setting supplied by drivers
(note the scan table does not get a map)
o defer node table allocation to lateattach so the driver has a chance
to set the max key id to size the key index map
o while here also defer the aid bitmap allocation
o add new ieee80211_find_rxnode_withkey api to find a sta/node entry
on frame receive with an optional h/w key index to use in checking
mapping table; also updates the map if it does a hash lookup and the
found node has a rx key index set in the unicast key; note this work
is separated from the old ieee80211_find_rxnode call so drivers do
not need to be aware of the new mechanism
o move some node table manipulation under the node table lock to close
a race on node delete
o add ieee80211_node_delucastkey to do the dirty work of deleting
unicast key state for a node (deletes any key and handles key map
references)
Ath driver:
o nuke private sc_keyixmap mechansim in favor of net80211 support
o update key alloc api
These changes close several race conditions for the ath driver operating
in ap mode. Other drivers should see no change. Station mode operation
for ath no longer uses the key index map but performance tests show no
noticeable change and this will be fixed when the scan table is eliminated
with the new scanning support.
Tested by: Michal Mertl, avatar, others
Reviewed by: avatar, others
MFC after: 2 weeks
entry points that will be inserted over the life-time of the 6.x branch,
including for:
- New struct file labeling (void * already added to struct file), events,
access control checks.
- Additional struct mount access control checks, internalization/
externalization.
- mac_check_cap()
- System call enter/exit check and event.
- Socket and vnode ioctl entry points.
MFC after: 3 days
