Userland should be able to trust the pid and uid of the sender of a
signal if the si_code is SI_TKILL.
Unfortunately, the kernel has historically allowed sigqueueinfo() to
send any si_code at all (as long as it was negative - to distinguish it
from kernel-generated signals like SIGILL etc), so it could spoof a
SI_TKILL with incorrect siginfo values.
Happily, it looks like glibc has always set si_code to the appropriate
SI_QUEUE, so there are probably no actual user code that ever uses
anything but the appropriate SI_QUEUE flag.
So just tighten the check for si_code (we used to allow any negative
value), and add a (one-time) warning in case there are binaries out
there that might depend on using other si_code values.
commit 9284bcf checks for proper length of iov entries in
blk_rq_map_user_iov(). But if the map is unaligned, kernel
will break out the loop without checking for the proper length.
So we need to check the proper length before the unalign check.
The sctp_asoc_get_hmac() function iterates through a peer's hmac_ids
array and attempts to ensure that only a supported hmac entry is
returned. The current code fails to do this properly - if the last id
in the array is out of range (greater than SCTP_AUTH_HMAC_ID_MAX), the
id integer remains set after exiting the loop, and the address of an
out-of-bounds entry will be returned and subsequently used in the parent
function, causing potentially ugly memory corruption. This patch resets
the id integer to 0 on encountering an invalid id so that NULL will be
returned after finishing the loop if no valid ids are found.
Signed-off-by: Dan Rosenberg <drosenberg@vsecurity.com> Acked-by: Vlad Yasevich <vladislav.yasevich@hp.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Don't forget to release the module refcnt if seq_open() returns failure.
Signed-off-by: Li Zefan <lizf@cn.fujitsu.com> Cc: J. Bruce Fields <bfields@fieldses.org> Cc: Neil Brown <neilb@suse.de> Cc: Trond Myklebust <Trond.Myklebust@netapp.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
The value of max_output and step_output registers isn't read from the
respective registers. As a result, zero values are returned to the
user through the respective sysfs attributes, instead of the actual
fan control settings.
The problem is fixed by updating the fan max output and fan step
output information from data in registers.
Signed-off-by: Guenter Roeck <guenter.roeck@ericsson.com> Signed-off-by: Jean Delvare <khali@linux-fr.org> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Add necessary alias to autoload ip6ip6 tunnel module.
Signed-off-by: Stephen Hemminger <shemminger@vyatta.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Since a8f80e8ff94ecba629542d9b4b5f5a8ee3eb565c any process with
CAP_NET_ADMIN may load any module from /lib/modules/. This doesn't mean
that CAP_NET_ADMIN is a superset of CAP_SYS_MODULE as modules are
limited to /lib/modules/**. However, CAP_NET_ADMIN capability shouldn't
allow anybody load any module not related to networking.
This patch restricts an ability of autoloading modules to netdev modules
with explicit aliases. This fixes CVE-2011-1019.
Arnd Bergmann suggested to leave untouched the old pre-v2.6.32 behavior
of loading netdev modules by name (without any prefix) for processes
with CAP_SYS_MODULE to maintain the compatibility with network scripts
that use autoloading netdev modules by aliases like "eth0", "wlan0".
Currently there are only three users of the feature in the upstream
kernel: ipip, ip_gre and sit.
root@albatros:~# capsh --drop=$(seq -s, 0 11),$(seq -s, 13 34) --
root@albatros:~# grep Cap /proc/$$/status
CapInh: 0000000000000000
CapPrm: fffffff800001000
CapEff: fffffff800001000
CapBnd: fffffff800001000
root@albatros:~# modprobe xfs
FATAL: Error inserting xfs
(/lib/modules/2.6.38-rc6-00001-g2bf4ca3/kernel/fs/xfs/xfs.ko): Operation not permitted
root@albatros:~# lsmod | grep xfs
root@albatros:~# ifconfig xfs
xfs: error fetching interface information: Device not found
root@albatros:~# lsmod | grep xfs
root@albatros:~# lsmod | grep sit
root@albatros:~# ifconfig sit
sit: error fetching interface information: Device not found
root@albatros:~# lsmod | grep sit
root@albatros:~# ifconfig sit0
sit0 Link encap:IPv6-in-IPv4
NOARP MTU:1480 Metric:1
root@albatros:~# lsmod | grep sit
sit 10457 0
tunnel4 2957 1 sit
For CAP_SYS_MODULE module loading is still relaxed:
[PG: in 2.6.34, the bare MODULE_ALIAS for ipip/tunl0 and ip_gre/gre0
didn't exist, but this adds the limited scope MODULE_ALIAS_NETDEV ones]
Signed-off-by: Vasiliy Kulikov <segoon@openwall.com> Signed-off-by: Michael Tokarev <mjt@tls.msk.ru> Acked-by: David S. Miller <davem@davemloft.net> Acked-by: Kees Cook <kees.cook@canonical.com> Signed-off-by: James Morris <jmorris@namei.org> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
In x25_link_free(), we destroy 'nb' before dereferencing
'nb->dev'. Don't do this, because 'nb' might be freed
by then.
Reported-by: Randy Dunlap <randy.dunlap@oracle.com> Tested-by: Randy Dunlap <randy.dunlap@oracle.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Commit 1a855a0606 (2.6.37-rc4) fixed a problem where devices were
re-added when they shouldn't be but caused a regression in a less
common case that means sometimes devices cannot be re-added when they
should be.
In particular, when re-adding a device to an array without metadata
we should always access the device, but after the above commit we
didn't.
This patch sets the In_sync flag in that case so that the re-add
succeeds.
This patch is suitable for any -stable kernel to which 1a855a0606 was
applied.
Signed-off-by: NeilBrown <neilb@suse.de> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
posix-cpu-timers.c correctly assumes that the dying process does
posix_cpu_timers_exit_group() and removes all !CPUCLOCK_PERTHREAD
timers from signal->cpu_timers list.
But, it also assumes that timer->it.cpu.task is always the group
leader, and thus the dead ->task means the dead thread group.
This is obviously not true after de_thread() changes the leader.
After that almost every posix_cpu_timer_ method has problems.
It is not simple to fix this bug correctly. First of all, I think
that timer->it.cpu should use struct pid instead of task_struct.
Also, the locking should be reworked completely. In particular,
tasklist_lock should not be used at all. This all needs a lot of
nontrivial and hard-to-test changes.
Change __exit_signal() to do posix_cpu_timers_exit_group() when
the old leader dies during exec. This is not the fix, just the
temporary hack to hide the problem for 2.6.37 and stable. IOW,
this is obviously wrong but this is what we currently have anyway:
cpu timers do not work after mt exec.
In theory this change adds another race. The exiting leader can
detach the timers which were attached to the new leader. However,
the window between de_thread() and release_task() is small, we
can pretend that sys_timer_create() was called before de_thread().
When stacking devices, a request_queue is not always available. This
forced us to have a no_cluster flag in the queue_limits that could be
used as a carrier until the request_queue had been set up for a
metadevice.
There were several problems with that approach. First of all it was up
to the stacking device to remember to set queue flag after stacking had
completed. Also, the queue flag and the queue limits had to be kept in
sync at all times. We got that wrong, which could lead to us issuing
commands that went beyond the max scatterlist limit set by the driver.
The proper fix is to avoid having two flags for tracking the same thing.
We deprecate QUEUE_FLAG_CLUSTER and use the queue limit directly in the
block layer merging functions. The queue_limit 'no_cluster' is turned
into 'cluster' to avoid double negatives and to ease stacking.
Clustering defaults to being enabled as before. The queue flag logic is
removed from the stacking function, and explicitly setting the cluster
flag is no longer necessary in DM and MD.
Reported-by: Ed Lin <ed.lin@promise.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> Acked-by: Mike Snitzer <snitzer@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Sjoerd Simons reports that, without using position_fix=1, recording
experiences overruns. Work around that by applying the LPIB quirk
for his hardware.
Reported-and-tested-by: Sjoerd Simons <sjoerd@debian.org> Signed-off-by: Daniel T Chen <crimsun@ubuntu.com> Signed-off-by: Takashi Iwai <tiwai@suse.de> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Thus without the patch, with the boot parameters 'tcb selinux=0', adding
the above 'dont_measure obj_type=var_log_t' rule to the default IMA TCB
measurement policy, would result in nothing being measured. The patch
prevents the default TCB policy from being replaced.
Signed-off-by: Mimi Zohar <zohar@us.ibm.com> Cc: James Morris <jmorris@namei.org> Acked-by: Serge Hallyn <serge.hallyn@canonical.com> Cc: David Safford <safford@watson.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
use mv_xor_slot_cleanup() instead of __mv_xor_slot_cleanup() as the former function
aquires the spin lock that needed to protect the drivers data.
Signed-off-by: Saeed Bishara <saeed@marvell.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
The load_mixer_volumes() function, which can be triggered by
unprivileged users via the SOUND_MIXER_SETLEVELS ioctl, is vulnerable to
a buffer overflow. Because the provided "name" argument isn't
guaranteed to be NULL terminated at the expected 32 bytes, it's possible
to overflow past the end of the last element in the mixer_vols array.
Further exploitation can result in an arbitrary kernel write (via
subsequent calls to load_mixer_volumes()) leading to privilege
escalation, or arbitrary kernel reads via get_mixer_levels(). In
addition, the strcmp() may leak bytes beyond the mixer_vols array.
Signed-off-by: Dan Rosenberg <drosenberg@vsecurity.com> Signed-off-by: Takashi Iwai <tiwai@suse.de> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
This USB ID is for the WUBI-100GW 802.11g Wireless LAN USB Device that
uses p54usb.
Signed-off-by: Larry Finger <Larry.Finger@lwfinger.net> Signed-off-by: Eduardo Costa <ecosta.tmp@gmail.com> Signed-off-by: John W. Linville <linville@tuxdriver.com> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Source:
http://www.linuxant.com/pipermail/driverloader/2005q3/002307.html
http://wireless.kernel.org/en/users/Drivers/p54/devices (by M. Davis)
Signed-off-by: Christian Lamparter <chunkeey@googlemail.com> Signed-off-by: John W. Linville <linville@tuxdriver.com> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Add an unusual_devs entry for the Samsung YP-CP3 MP4 player.
User was getting the following errors in dmesg:
usb 2-6: reset high speed USB device using ehci_hcd and address 2
usb 2-6: reset high speed USB device using ehci_hcd and address 2
usb 2-6: reset high speed USB device using ehci_hcd and address 2
usb 2-6: USB disconnect, address 2
sd 3:0:0:0: [sdb] Assuming drive cache: write through
sdb:<2>ldm_validate_partition_table(): Disk read failed.
Dev sdb: unable to read RDB block 0
unable to read partition table
[PG: change USB_ --> US_ to match 2.6.34.x naming conventions]
Signed-off-by: Vitaly Kuznetsov <vitty@altlinux.ru> Acked-by: Alan Stern <stern@rowland.harvard.edu> CC: Matthew Dharm <mdharm-usb@one-eyed-alien.net> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
The install_special_mapping routine (used, for example, to setup the
vdso) skips the security check before insert_vm_struct, allowing a local
attacker to bypass the mmap_min_addr security restriction by limiting
the available pages for special mappings.
bprm_mm_init() also skips the check, and although I don't think this can
be used to bypass any restrictions, I don't see any reason not to have
the security check.
It's worth noting that Red Hat are shipping with mmap_min_addr set to
4096.
Signed-off-by: Tavis Ormandy <taviso@google.com> Acked-by: Kees Cook <kees@ubuntu.com> Acked-by: Robert Swiecki <swiecki@google.com>
[ Changed to not drop the error code - akpm ] Reviewed-by: James Morris <jmorris@namei.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
The port data structure related to fc_host statistics collection is
not initialized. This causes system crash when reading the fc_host
statistics. The fix is to initialize port structure during driver
attach.
Signed-off-by: Krishna Gudipati <kgudipat@brocade.com> Signed-off-by: James Bottomley <James.Bottomley@suse.de> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
There is a window between hidraw_table check and its dereference.
In that window, the device may be unplugged and removed form the
system and we will then dereference NULL.
Lock that place properly so that either we get NULL and jump out or we
can work with real pointer.
[PG: slightly/trivially reworked for backport to 34]
On platforms with Intel 7500 chipset, there were some reports of system
hang/NMI's during kexec/kdump in the presence of interrupt-remapping enabled.
During kdump, there is a window where the devices might be still using old
kernel's interrupt information, while the kdump kernel is coming up. This can
cause vt-d faults as the interrupt configuration from the old kernel map to
null IRTE entries in the new kernel etc. (with out interrupt-remapping enabled,
we still have the same issue but in this case we will see benign spurious
interrupt hit the new kernel).
Based on platform config settings, these platforms seem to generate NMI/SMI
when a vt-d fault happens and there were reports that the resulting SMI causes
the system to hang.
Fix it by masking vt-d spec defined errors to platform error reporting logic.
VT-d spec related errors are already handled by the VT-d OS code, so need to
report the same error through other channels.
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
LKML-Reference: <1291667190.2675.8.camel@sbsiddha-MOBL3.sc.intel.com> Reported-by: Max Asbock <masbock@linux.vnet.ibm.com> Reported-and-tested-by: Takao Indoh <indou.takao@jp.fujitsu.com> Acked-by: Chris Wright <chrisw@sous-sol.org> Acked-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
In x2apic mode, we need to set the upper address register of the fault
handling interrupt register of the vt-d hardware. Without this
irq migration of the vt-d fault handling interrupt is broken.
Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
LKML-Reference: <1291225233.2648.39.camel@sbsiddha-MOBL3> Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com> Acked-by: Chris Wright <chrisw@sous-sol.org> Tested-by: Takao Indoh <indou.takao@jp.fujitsu.com> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Fault handling is getting enabled after enabling the interrupt-remapping (as
the success of interrupt-remapping can affect the apic mode and hence the
fault handling mode).
Hence there can potentially be some faults between the window of enabling
interrupt-remapping in the vt-d and the fault-handling of the vt-d units.
Handle any previous faults after enabling the vt-d fault handling.
For v2.6.38 cleanup, need to check if we can remove the dmar_fault() in the
enable_intr_remapping() and see if we can enable fault handling along with
enabling intr-remapping.
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
LKML-Reference: <20101201062244.630417138@intel.com> Acked-by: Chris Wright <chrisw@sous-sol.org> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Interrupt-remapping gets enabled very early in the boot, as it determines the
apic mode that the processor can use. And the current code enables the vt-d
fault handling before the setup_local_APIC(). And hence the APIC LDR registers
and data structure in the memory may not be initialized. So the vt-d fault
handling in logical xapic/x2apic modes were broken.
Fix this by enabling the vt-d fault handling in the end_local_APIC_setup()
A cleaner fix of enabling fault handling while enabling intr-remapping
will be addressed for v2.6.38. [ Enabling intr-remapping determines the
usage of x2apic mode and the apic mode determines the fault-handling
configuration. ]
Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
LKML-Reference: <20101201062244.541996375@intel.com> Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com> Acked-by: Chris Wright <chrisw@sous-sol.org> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
The vdso Makefile passes linker-style -m options not to the linker but
to gcc. This happens to work with earlier gcc, but fails with gcc
4.6. Pass gcc-style -m options, instead.
Note: all currently supported versions of gcc supports -m32, so there
is no reason to conditionalize it any more.
Reported-by: H. J. Lu <hjl.tools@gmail.com> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
LKML-Reference: <tip-*@git.kernel.org> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
The file_ops struct for the "trace" special file defined llseek as seq_lseek().
However, if the file was opened for writing only, seq_open() was not called,
and the seek would dereference a null pointer, file->private_data.
This patch introduces a new wrapper for seq_lseek() which checks if the file
descriptor is opened for reading first. If not, it does nothing.
Signed-off-by: Slava Pestov <slavapestov@google.com>
LKML-Reference: <1290640396-24179-1-git-send-email-slavapestov@google.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
With v0.90 metadata, a hot-spare does not become a full member of the
array until recovery is complete. So if we re-add such a device to
the array, we know that all of it is as up-to-date as the event count
would suggest, and so it a bitmap-based recovery is possible.
However with v1.x metadata, the hot-spare immediately becomes a full
member of the array, but it record how much of the device has been
recovered. If the array is stopped and re-assembled recovery starts
from this point.
When such a device is hot-added to an array we currently lose the 'how
much is recovered' information and incorrectly included it as a full
in-sync member (after bitmap-based fixup).
This is wrong and unsafe and could corrupt data.
So be more careful about setting saved_raid_disk - which is what
guides the re-adding of devices back into an array.
The new code matches the code in slot_store which does a similar
thing, which is encouraging.
In these situations, you are usually trying to connect to a new AP, so
keeping TKIP countermeasures active is confusing. This is already how
the driver behaves (inadvertently). However, querying SIOCGIWAUTH may
tell userspace that countermeasures are active when they aren't.
Clear the setting so that the reporting matches what the driver has
done..
Signed-off by: David Kilroy <kilroyd@googlemail.com> Signed-off-by: John W. Linville <linville@tuxdriver.com> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Enable the port when disabling countermeasures, and disable it on
enabling countermeasures.
This bug causes the response of the system to certain attacks to be
ineffective.
It also prevents wpa_supplicant from getting scan results, as
wpa_supplicant disables countermeasures on startup - preventing the
hardware from scanning.
wpa_supplicant works with ap_mode=2 despite this bug because the commit
handler re-enables the port.
The log tends to look like:
State: DISCONNECTED -> SCANNING
Starting AP scan for wildcard SSID
Scan requested (ret=0) - scan timeout 5 seconds
EAPOL: disable timer tick
EAPOL: Supplicant port status: Unauthorized
Scan timeout - try to get results
Failed to get scan results
Failed to get scan results - try scanning again
Setting scan request: 1 sec 0 usec
Starting AP scan for wildcard SSID
Scan requested (ret=-1) - scan timeout 5 seconds
Failed to initiate AP scan.
Reported by: Giacomo Comes <comes@naic.edu>
Signed-off by: David Kilroy <kilroyd@googlemail.com> Signed-off-by: John W. Linville <linville@tuxdriver.com> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: Alexey Starikovskiy <astarikovskiy@suse.de> Signed-off-by: Len Brown <len.brown@intel.com> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Some Panasonic Toughbooks create nodes in module level code.
Module level code is the executable AML code outside of control method,
for example, below AML code creates a node \_SB.PCI0.GFX0.DD02.CUBL
If (\_OSI ("Windows 2006"))
{
Scope (\_SB.PCI0.GFX0.DD02)
{
Name (CUBL, Ones)
...
}
}
Scope() op does not actually create a new object, it refers to an
existing object(\_SB.PCI0.GFX0.DD02 in above example). However, for
Scope(), we want to indeed open a new scope, so the child nodes(CUBL in
above example) can be created correctly under it.
https://bugzilla.kernel.org/show_bug.cgi?id=19462
Signed-off-by: Bob Moore <robert.moore@intel.com> Signed-off-by: Lin Ming <ming.m.lin@intel.com> Signed-off-by: Len Brown <len.brown@intel.com> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
The user-space hibernation sends a wrong notification after the image
restoration because of thinko for the file flag check. RDONLY
corresponds to hibernation and WRONLY to restoration, confusingly.
Signed-off-by: Takashi Iwai <tiwai@suse.de> Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
In ib_uverbs_poll_cq() code there is a potential integer overflow if
userspace passes in a large cmd.ne. The calls to kmalloc() would
allocate smaller buffers than intended, leading to memory corruption.
There iss also an information leak if resp wasn't all used.
Unprivileged userspace may call this function, although only if an
RDMA device that uses this function is present.
Fix this by copying CQ entries one at a time, which avoids the
allocation entirely, and also by moving this copying into a function
that makes sure to initialize all memory copied to userspace.
Special thanks to Jason Gunthorpe <jgunthorpe@obsidianresearch.com>
for his help and advice.
Signed-off-by: Dan Carpenter <error27@gmail.com>
[ Monkey around with things a bit to avoid bad code generation by gcc
when designated initializers are used. - Roland ]
Signed-off-by: Roland Dreier <rolandd@cisco.com> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
When matching error address to the range contained by one memory node,
we're in valid range when node interleaving
1. is disabled, or
2. enabled and when the address bits we interleave on match the
interleave selector on this node (see the "Node Interleaving" section in
the BKDG for an enlightening example).
Thus, when we early-exit, we need to reverse the compound logic
statement properly.
Signed-off-by: Borislav Petkov <borislav.petkov@amd.com> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
When an xprt is created, it has a refcount of 1, and XPT_BUSY is set.
The refcount is *not* owned by the thread that created the xprt
(as is clear from the fact that creators never put the reference).
Rather, it is owned by the absence of XPT_DEAD. Once XPT_DEAD is set,
(And XPT_BUSY is clear) that initial reference is dropped and the xprt
can be freed.
So when a creator clears XPT_BUSY it is dropping its only reference and
so must not touch the xprt again.
However svc_recv, after calling ->xpo_accept (and so getting an XPT_BUSY
reference on a new xprt), calls svc_xprt_recieved. This clears
XPT_BUSY and then svc_xprt_enqueue - this last without owning a reference.
This is dangerous and has been seen to leave svc_xprt_enqueue working
with an xprt containing garbage.
So we need to hold an extra counted reference over that call to
svc_xprt_received.
For safety, any time we clear XPT_BUSY and then use the xprt again, we
first get a reference, and the put it again afterwards.
Note that svc_close_all does not need this extra protection as there are
no threads running, and the final free can only be called asynchronously
from such a thread.
Signed-off-by: NeilBrown <neilb@suse.de> Signed-off-by: J. Bruce Fields <bfields@redhat.com> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
The commit 129a84de2347002f09721cda3155ccfd19fade40 (locks: fix F_GETLK
regression (failure to find conflicts)) fixed the posix_test_lock()
function by itself, however, its usage in NFS changed by the commit 9d6a8c5c213e34c475e72b245a8eb709258e968c (locks: give posix_test_lock
same interface as ->lock) remained broken - subsequent NFS-specific
locking code received F_UNLCK instead of the user-specified lock type.
To fix the problem, fl->fl_type needs to be saved before the
posix_test_lock() call and restored if no local conflicts were reported.
Reference: https://bugzilla.kernel.org/show_bug.cgi?id=23892 Tested-by: Alexander Morozov <amorozov@etersoft.ru> Signed-off-by: Sergey Vlasov <vsu@altlinux.ru> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
If vfs_getattr in fill_post_wcc returns an error, we don't
set fh_post_change.
For NFSv4, this can result in set_change_info triggering a BUG_ON.
i.e. fh_post_saved being zero isn't really a bug.
So:
- instead of BUGging when fh_post_saved is zero, just clear ->atomic.
- if vfs_getattr fails in fill_post_wcc, take a copy of i_ctime anyway.
This will be used i seg_change_info, but not overly trusted.
- While we are there, remove the pointless 'if' statements in set_change_info.
There is no harm setting all the values.
Signed-off-by: NeilBrown <neilb@suse.de> Signed-off-by: J. Bruce Fields <bfields@redhat.com> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
After a few unsuccessful NFS mount attempts in which the client and
server cannot agree on an authentication flavor both support, the
client panics. nfs_umount() is invoked in the kernel in this case.
Turns out nfs_umount()'s UMNT RPC invocation causes the RPC client to
write off the end of the rpc_clnt's iostat array. This is because the
mount client's nrprocs field is initialized with the count of defined
procedures (two: MNT and UMNT), rather than the size of the client's
proc array (four).
The fix is to use the same initialization technique used by most other
upper layer clients in the kernel.
Introduced by commit 0b524123, which failed to update nrprocs when
support was added for UMNT in the kernel.
BugLink: https://bugzilla.kernel.org/show_bug.cgi?id=24302 BugLink: http://bugs.launchpad.net/bugs/683938 Reported-by: Stefan Bader <stefan.bader@canonical.com> Tested-by: Stefan Bader <stefan.bader@canonical.com> Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
This fixes a bug as seen on 2.6.32 based kernels where timers got
enqueued on offline cpus.
If a cpu goes offline it might still have pending timers. These will
be migrated during CPU_DEAD handling after the cpu is offline.
However while the cpu is going offline it will schedule the idle task
which will then call tick_nohz_stop_sched_tick().
That function in turn will call get_next_timer_intterupt() to figure
out if the tick of the cpu can be stopped or not. If it turns out that
the next tick is just one jiffy off (delta_jiffies == 1)
tick_nohz_stop_sched_tick() incorrectly assumes that the tick should
not stop and takes an early exit and thus it won't update the load
balancer cpu.
Just afterwards the cpu will be killed and the load balancer cpu could
be the offline cpu.
On 2.6.32 based kernel get_nohz_load_balancer() gets called to decide
on which cpu a timer should be enqueued (see __mod_timer()). Which
leads to the possibility that timers get enqueued on an offline cpu.
These will never expire and can cause a system hang.
This has been observed 2.6.32 kernels. On current kernels
__mod_timer() uses get_nohz_timer_target() which doesn't have that
problem. However there might be other problems because of the too
early exit tick_nohz_stop_sched_tick() in case a cpu goes offline.
The easiest and probably safest fix seems to be to let
get_next_timer_interrupt() just lie and let it say there isn't any
pending timer if the current cpu is offline.
I also thought of moving migrate_[hr]timers() from CPU_DEAD to
CPU_DYING, but seeing that there already have been fixes at least in
the hrtimer code in this area I'm afraid that this could add new
subtle bugs.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <20101201091109.GA8984@osiris.boeblingen.de.ibm.com> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
This patch fixes a hang observed with 2.6.32 kernels where timers got enqueued
on offline cpus.
printk_needs_cpu() may return 1 if called on offline cpus. When a cpu gets
offlined it schedules the idle process which, before killing its own cpu, will
call tick_nohz_stop_sched_tick(). That function in turn will call
printk_needs_cpu() in order to check if the local tick can be disabled. On
offline cpus this function should naturally return 0 since regardless if the
tick gets disabled or not the cpu will be dead short after. That is besides the
fact that __cpu_disable() should already have made sure that no interrupts on
the offlined cpu will be delivered anyway.
In this case it prevents tick_nohz_stop_sched_tick() to call
select_nohz_load_balancer(). No idea if that really is a problem. However what
made me debug this is that on 2.6.32 the function get_nohz_load_balancer() is
used within __mod_timer() to select a cpu on which a timer gets enqueued. If
printk_needs_cpu() returns 1 then the nohz_load_balancer cpu doesn't get
updated when a cpu gets offlined. It may contain the cpu number of an offline
cpu. In turn timers get enqueued on an offline cpu and not very surprisingly
they never expire and cause system hangs.
This has been observed 2.6.32 kernels. On current kernels __mod_timer() uses
get_nohz_timer_target() which doesn't have that problem. However there might be
other problems because of the too early exit tick_nohz_stop_sched_tick() in
case a cpu goes offline.
Easiest way to fix this is just to test if the current cpu is offline and call
printk_tick() directly which clears the condition.
Alternatively I tried a cpu hotplug notifier which would clear the condition,
however between calling the notifier function and printk_needs_cpu() something
could have called printk() again and the problem is back again. This seems to
be the safest fix.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <20101126120235.406766476@de.ibm.com> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
BugLink: https://launchpad.net/bugs/595482
The original reporter states that audible playback from the internal
speaker is inaudible despite the hardware being properly detected. To
work around this symptom, he uses the model=lg quirk to properly enable
both playback, capture, and jack sense. Another user corroborates this
workaround on separate hardware. Add this PCI SSID to the quirk table
to enable it for further LG P1 Expresses.
Reported-and-tested-by: Philip Peitsch <philip.peitsch@gmail.com> Tested-by: nikhov Signed-off-by: Daniel T Chen <crimsun@ubuntu.com> Signed-off-by: Takashi Iwai <tiwai@suse.de> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
When we're using MWAIT for play_dead, explicitly CLFLUSH the cache
line before executing MONITOR. This is a potential workaround for the
Xeon 7400 erratum AAI65 after having a spurious wakeup and returning
around the loop. "Potential" here because it is not certain that that
erratum could actually trigger; however, the CLFLUSH should be
harmless.
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> Acked-by: Venkatesh Pallipadi <venki@google.com> Cc: Asit Mallick <asit.k.mallick@intel.com> Cc: Arjan van de Ven <arjan@linux.kernel.org> Cc: Len Brown <lenb@kernel.org> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
On processors with hyperthreading, when only one thread is offlined
the other thread can cause a spurious wakeup on the idled thread. We
do not want to re-WBINVD when that happens.
Ideally, we should simply skip WBINVD unless we're the last thread on
a particular core to shut down, but there might be similar issues
elsewhere in the system.
Thus, revert to previous behavior of only WBINVD outside the loop.
Partly as a result, remove the mb()'s around it: they are not
necessary since wbinvd() is a serializing instruction, but they were
intended to make sure the compiler didn't do any funny loop
optimizations.
Reported-by: Asit Mallick <asit.k.mallick@intel.com> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> Cc: Arjan van de Ven <arjan@linux.kernel.org> Cc: Len Brown <lenb@kernel.org> Cc: Venkatesh Pallipadi <venki@google.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <tip-ea53069231f9317062910d6e772cca4ce93de8c8@git.kernel.org> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
The code in native_play_dead() has a number of problems:
1. We should use MWAIT when available, to put ourselves into a deeper
sleep state.
2. We use the existence of CLFLUSH to determine if WBINVD is safe, but
that is totally bogus -- WBINVD is 486+, whereas CLFLUSH is a much
later addition.
3. We should do WBINVD inside the loop, just in case of something like
setting an A bit on page tables. Pointed out by Arjan van de Ven.
This code is based in part of a previous patch by Venki Pallipadi, but
unlike that patch this one keeps all the detection code local instead
of pre-caching a bunch of information. We're shutting down the CPU;
there is absolutely no hurry.
This patch moves all the code to C and deletes the global
wbinvd_halt() which is broken anyway.
Originally-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> Reviewed-by: Arjan van de Ven <arjan@linux.intel.com> Cc: Len Brown <lenb@kernel.org> Cc: Venkatesh Pallipadi <venki@google.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <20090522232230.162239000@intel.com> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
We have MWAIT constants spread across three different .c files, for no
good reason. Move them all into a common header file.
[PG: required for cherry pick of ce5f68246b - to avoid dup. mwait
fields in smpboot.c; drop intel_idle.c chunk, as 34 doesnt have it]
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> Reviewed-by: Arjan van de Ven <arjan@linux.intel.com> Cc: Len Brown <lenb@kernel.org>
LKML-Reference: <tip-*@git.kernel.org> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
x25 does not decrement the network device reference counts on module unload.
Thus unregistering any pre-existing interface after unloading the x25 module
hangs and results in
unregister_netdevice: waiting for tap0 to become free. Usage count = 1
This patch decrements the reference counts of all interfaces in x25_link_free,
the way it is already done in x25_link_device_down for NETDEV_DOWN events.
Signed-off-by: Apollon Oikonomopoulos <apollon@noc.grnet.gr> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
If we break the loop when there are still skbs in tq and no skb in
rq, the skbs will be left in txq until new skbs are enqueued into rq.
In rare cases, no new skb is queued, then these skbs will stay in rq
forever.
After this patch, if tq isn't empty when we break the loop, we goto
resched directly.
Signed-off-by: Changli Gao <xiaosuo@gmail.com> Signed-off-by: Jamal Hadi Salim <hadi@cyberus.ca> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Unconditional use of skb->dev won't work here,
try to fetch the econet device via skb_dst()->dev
instead.
Suggested by Eric Dumazet.
Reported-by: Nelson Elhage <nelhage@ksplice.com> Tested-by: Nelson Elhage <nelhage@ksplice.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
We need to drop the mutex and do a dev_put, so set an error code and break like
the other paths, instead of returning directly.
Signed-off-by: Nelson Elhage <nelhage@ksplice.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Pavel Emelyanov tried to fix a race between sk_filter_(de|at)tach and
sk_clone() in commit 47e958eac280c263397
Problem is we can have several clones sharing a common sk_filter, and
these clones might want to sk_filter_attach() their own filters at the
same time, and can overwrite old_filter->rcu, corrupting RCU queues.
We can not use filter->rcu without being sure no other thread could do
the same thing.
Switch code to a more conventional ref-counting technique : Do the
atomic decrement immediately and queue one rcu call back when last
reference is released.
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
The returned slave is incorrect, if the net device under check is not
charged yet by the master.
Signed-off-by: Hillf Danton <dhillf@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Regarding benet be_cmd_multicast_set() function, now using
netdev_for_each_mc_addr() helper for mac address copy, but
when copying to req->mac[] did not increase of the index.
Cc: Sathya Perla <sathyap@serverengines.com> Cc: Subbu Seetharaman <subbus@serverengines.com> Cc: Sarveshwar Bandi <sarveshwarb@serverengines.com> Cc: Ajit Khaparde <ajitk@serverengines.com> Signed-off-by: Joe Jin <joe.jin@oracle.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
packet_getname_spkt() doesn't initialize all members of sa_data field of
sockaddr struct if strlen(dev->name) < 13. This structure is then copied
to userland. It leads to leaking of contents of kernel stack memory.
We have to fully fill sa_data with strncpy() instead of strlcpy().
The same with packet_getname(): it doesn't initialize sll_pkttype field of
sockaddr_ll. Set it to zero.
Signed-off-by: Vasiliy Kulikov <segooon@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Its easy to eat all kernel memory and trigger NMI watchdog, using an
exploit program that queues unix sockets on top of others.
lkml ref : http://lkml.org/lkml/2010/11/25/8
This mechanism is used in applications, one choice we have is to have a
recursion limit.
Other limits might be needed as well (if we queue other types of files),
since the passfd mechanism is currently limited by socket receive queue
sizes only.
Add a recursion_level to unix socket, allowing up to 4 levels.
Each time we send an unix socket through sendfd mechanism, we copy its
recursion level (plus one) to receiver. This recursion level is cleared
when socket receive queue is emptied.
[PG: slight modifications required due to absense of 7361c36c5 in 34]
Reported-by: Марк Коренберг <socketpair@gmail.com> Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Vegard Nossum found a unix socket OOM was possible, posting an exploit
program.
My analysis is we can eat all LOWMEM memory before unix_gc() being
called from unix_release_sock(). Moreover, the thread blocked in
unix_gc() can consume huge amount of time to perform cleanup because of
huge working set.
One way to handle this is to have a sensible limit on unix_tot_inflight,
tested from wait_for_unix_gc() and to force a call to unix_gc() if this
limit is hit.
This solves the OOM and also reduce overall latencies, and should not
slowdown normal workloads.
Reported-by: Vegard Nossum <vegard.nossum@gmail.com> Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
sysctl_tcp_tso_win_divisor might be set to zero while one cpu runs in
tcp_tso_should_defer(). Make sure we dont allow a divide by zero by
reading sysctl_tcp_tso_win_divisor exactly once.
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
The bug has to do with boundary checks on the initial receive window.
If the initial receive window falls between init_cwnd and the
receive window specified by the user, the initial window is incorrectly
brought down to init_cwnd. The correct behavior is to allow it to
remain unchanged.
Signed-off-by: Nandita Dukkipati <nanditad@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Reported-by: Min Zhang <mzhang@mvista.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
As noted by Steve Chen, since commit f5fff5dc8a7a3f395b0525c02ba92c95d42b7390 ("tcp: advertise MSS
requested by user") we can end up with a situation where
tcp_select_initial_window() does a divide by a zero (or
even negative) mss value.
The problem is that sometimes we effectively subtract
TCPOLEN_TSTAMP_ALIGNED and/or TCPOLEN_MD5SIG_ALIGNED from the mss.
Fix this by increasing the minimum from 8 to 64.
Reported-by: Steve Chen <schen@mvista.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Alexey Kuznetsov noticed a regression introduced by
commit f1ecd5d9e7366609d640ff4040304ea197fbc618
("Revert Backoff [v3]: Revert RTO on ICMP destination unreachable")
The RTO and timer modification code added to tcp_v4_err()
doesn't check sock_owned_by_user(), which if true means we
don't have exclusive access to the socket and therefore cannot
modify it's critical state.
Just skip this new code block if sock_owned_by_user() is true
and eliminate the now superfluous sock_owned_by_user() code
block contained within.
Reported-by: Alexey Kuznetsov <kuznet@ms2.inr.ac.ru> Signed-off-by: David S. Miller <davem@davemloft.net> CC: Damian Lukowski <damian@tvk.rwth-aachen.de> Acked-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Brad Spengler published a local memory-allocation DoS that
evades the OOM-killer (though not the virtual memory RLIMIT):
http://www.grsecurity.net/~spender/64bit_dos.c
execve()->copy_strings() can allocate a lot of memory, but
this is not visible to oom-killer, nobody can see the nascent
bprm->mm and take it into account.
With this patch get_arg_page() increments current's MM_ANONPAGES
counter every time we allocate the new page for argv/envp. When
do_execve() succeds or fails, we change this counter back.
Technically this is not 100% correct, we can't know if the new
page is swapped out and turn MM_ANONPAGES into MM_SWAPENTS, but
I don't think this really matters and everything becomes correct
once exec changes ->mm or fails.
Compared to upstream:
before 2.6.36 kernel, oom-killer's badness() takes
mm->total_vm into account and nothing else. So
acct_arg_size() has to play with this counter too.
There is a possibility malicious users can get limited information about
uninitialized stack mem array. Even if sk_run_filter() result is bound
to packet length (0 .. 65535), we could imagine this can be used by
hostile user.
Initializing mem[] array, like Dan Rosenberg suggested in his patch is
expensive since most filters dont even use this array.
Its hard to make the filter validation in sk_chk_filter(), because of
the jumps. This might be done later.
In this patch, I use a bitmap (a single long var) so that only filters
using mem[] loads/stores pay the price of added security checks.
For other filters, additional cost is a single instruction.
[ Since we access fentry->k a lot now, cache it in a local variable
and mark filter entry pointer as const. -DaveM ]
Reported-by: Dan Rosenberg <drosenberg@vsecurity.com> Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
[PG: back in 2.6.34, the file was called debug.c, not debugfs.c]
Signed-off-by: Dave Jones <davej@redhat.com> Signed-off-by: Len Brown <len.brown@intel.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Don't declare variable sized array of iovecs on the stack since this
could cause stack overflow if msg->msgiovlen is large. Instead, coalesce
the user-supplied data into a new buffer and use a single iovec for it.
Signed-off-by: Phil Blundell <philb@gnu.org> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
There are many WARNINGs like the following reported nowadays:
WARNING: at drivers/tty/tty_io.c:1331 tty_open+0x2a2/0x49a()
Hardware name: Latitude E6500
Modules linked in:
Pid: 1207, comm: plymouthd Not tainted 2.6.37-rc3-mmotm1123 #3
Call Trace:
[<ffffffff8103b189>] warn_slowpath_common+0x80/0x98
[<ffffffff8103b1b6>] warn_slowpath_null+0x15/0x17
[<ffffffff8128a3ab>] tty_open+0x2a2/0x49a
[<ffffffff810fd53f>] chrdev_open+0x11d/0x146
...
This means tty_reopen is called without TTY_LDISC set. For further
considerations, note tty_lock is held in tty_open. TTY_LDISC is cleared in:
1) __tty_hangup from tty_ldisc_hangup to tty_ldisc_enable. During this
section tty_lock is held. However tty_lock is temporarily dropped in
the middle of the function by tty_ldisc_hangup.
2) tty_release via tty_ldisc_release till the end of tty existence. If
tty->count <= 1, tty_lock is taken, TTY_CLOSING bit set and then
tty_ldisc_release called. tty_reopen checks TTY_CLOSING before checking
TTY_LDISC.
3) tty_set_ldisc from tty_ldisc_halt to tty_ldisc_enable. We:
* take tty_lock, set TTY_LDISC_CHANGING, put tty_lock
* call tty_ldisc_halt (clear TTY_LDISC), tty_lock is _not_ held
* do some other work
* take tty_lock, call tty_ldisc_enable (set TTY_LDISC), put
tty_lock
I cannot see how 2) can be a problem, as there I see no race. OTOH, 1)
and 3) can happen without problems. This patch the case 3) by checking
TTY_LDISC_CHANGING along with TTY_CLOSING in tty_reopen. 1) will be
fixed in the following patch.
Nicely reproducible with two processes:
while (1) {
fd = open("/dev/ttyS1", O_RDWR);
if (fd < 0) {
warn("open");
continue;
}
close(fd);
}
--------
while (1) {
fd = open("/dev/ttyS1", O_RDWR);
ld1 = 0; ld2 = 2;
while (1) {
ioctl(fd, TIOCSETD, &ld1);
ioctl(fd, TIOCSETD, &ld2);
}
close(fd);
}
The PKT_CTRL_CMD_STATUS device ioctl retrieves a pointer to a
pktcdvd_device from the global pkt_devs array. The index into this
array is provided directly by the user and is a signed integer, so the
comparison to ensure that it falls within the bounds of this array will
fail when provided with a negative index.
This can be used to read arbitrary kernel memory or cause a crash due to
an invalid pointer dereference. This can be exploited by users with
permission to open /dev/pktcdvd/control (on many distributions, this is
readable by group "cdrom").
Signed-off-by: Dan Rosenberg <dan.j.rosenberg@gmail.com>
[ Rather than add a cast, just make the function take the right type -Linus ] Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
We leak at least 32bits of kernel memory to user land in tc dump,
because we dont init all fields (capab ?) of the dumped structure.
Use C99 initializers so that holes and non explicit fields are zeroed.
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
structure tc_nat isn't too big for stack, so we can put it in stack.
Signed-off-by: Changli Gao <xiaosuo@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
On each machine check all registers are revalidated. The save area for
the clock comparator however only contains the upper most seven bytes
of the former contents, if valid.
Therefore the machine check handler uses a store clock instruction to
get the current time and writes that to the clock comparator register
which in turn will generate an immediate timer interrupt.
However within the lowcore the expected time of the next timer
interrupt is stored. If the interrupt happens before that time the
handler won't be called. In turn the clock comparator won't be
reprogrammed and therefore the interrupt condition stays pending which
causes an interrupt loop until the expected time is reached.
On NOHZ machines this can result in unresponsive machines since the
time of the next expected interrupted can be a couple of days in the
future.
To fix this just revalidate the clock comparator register with the
expected value.
In addition the special handling for udelay must be changed as well.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
This helps protect us from overflow issues down in the
individual protocol sendmsg/recvmsg handlers. Once
we hit INT_MAX we truncate out the rest of the iovec
by setting the iov_len members to zero.
This works because:
1) For SOCK_STREAM and SOCK_SEQPACKET sockets, partial
writes are allowed and the application will just continue
with another write to send the rest of the data.
2) For datagram oriented sockets, where there must be a
one-to-one correspondance between write() calls and
packets on the wire, INT_MAX is going to be far larger
than the packet size limit the protocol is going to
check for and signal with -EMSGSIZE.
Based upon a patch by Linus Torvalds.
Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
In rds_cmsg_rdma_args(), the user-provided args->nr_local value is
restricted to less than UINT_MAX. This seems to need a tighter upper
bound, since the calculation of total iov_size can overflow, resulting
in a small sock_kmalloc() allocation. This would probably just result
in walking off the heap and crashing when calling rds_rdma_pages() with
a high count value. If it somehow doesn't crash here, then memory
corruption could occur soon after.
Signed-off-by: Dan Rosenberg <drosenberg@vsecurity.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Add missing check for capable(CAP_NET_ADMIN) in SIOCSIFADDR operation.
Signed-off-by: Phil Blundell <philb@gnu.org> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Later parts of econet_sendmsg() rely on saddr != NULL, so return early
with EINVAL if NULL was passed otherwise an oops may occur.
Signed-off-by: Phil Blundell <philb@gnu.org> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
rc2 kernel crashes when booting second cpu on this CONFIG_VMSPLIT_2G_OPT
laptop: whereas cloning from kernel to low mappings pgd range does need
to limit by both KERNEL_PGD_PTRS and KERNEL_PGD_BOUNDARY, cloning kernel
pgd range itself must not be limited by the smaller KERNEL_PGD_BOUNDARY.
Signed-off-by: Hugh Dickins <hughd@google.com>
LKML-Reference: <alpine.LSU.2.00.1008242235120.2515@sister.anvils> Signed-off-by: H. Peter Anvin <hpa@zytor.com> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
This patch fixes machine crashes which occur when heavily exercising the
CPU hotplug codepaths on a 32-bit kernel. These crashes are caused by
AMD Erratum 383 and result in a fatal machine check exception. Here's
the scenario:
1. On 32-bit, the swapper_pg_dir page table is used as the initial page
table for booting a secondary CPU.
2. To make this work, swapper_pg_dir needs a direct mapping of physical
memory in it (the low mappings). By adding those low, large page (2M)
mappings (PAE kernel), we create the necessary conditions for Erratum
383 to occur.
3. Other CPUs which do not participate in the off- and onlining game may
use swapper_pg_dir while the low mappings are present (when leave_mm is
called). For all steps below, the CPU referred to is a CPU that is using
swapper_pg_dir, and not the CPU which is being onlined.
4. The presence of the low mappings in swapper_pg_dir can result
in TLB entries for addresses below __PAGE_OFFSET to be established
speculatively. These TLB entries are marked global and large.
5. When the CPU with such TLB entry switches to another page table, this
TLB entry remains because it is global.
6. The process then generates an access to an address covered by the
above TLB entry but there is a permission mismatch - the TLB entry
covers a large global page not accessible to userspace.
7. Due to this permission mismatch a new 4kb, user TLB entry gets
established. Further, Erratum 383 provides for a small window of time
where both TLB entries are present. This results in an uncorrectable
machine check exception signalling a TLB multimatch which panics the
machine.
There are two ways to fix this issue:
1. Always do a global TLB flush when a new cr3 is loaded and the
old page table was swapper_pg_dir. I consider this a hack hard
to understand and with performance implications
2. Do not use swapper_pg_dir to boot secondary CPUs like 64-bit
does.
This patch implements solution 2. It introduces a trampoline_pg_dir
which has the same layout as swapper_pg_dir with low_mappings. This page
table is used as the initial page table of the booting CPU. Later in the
bringup process, it switches to swapper_pg_dir and does a global TLB
flush. This fixes the crashes in our test cases.
-v2: switch to swapper_pg_dir right after entering start_secondary() so
that we are able to access percpu data which might not be mapped in the
trampoline page table.
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
LKML-Reference: <20100816123833.GB28147@aftab> Signed-off-by: Borislav Petkov <borislav.petkov@amd.com> Signed-off-by: H. Peter Anvin <hpa@zytor.com> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
On certain VIA chipsets AES-CBC requires the input/output to be
a multiple of 64 bytes. We had a workaround for this but it was
buggy as it sent the whole input for processing when it is meant
to only send the initial number of blocks which makes the rest
a multiple of 64 bytes.
As expected this causes memory corruption whenever the workaround
kicks in.
Reported-by: Phil Sutter <phil@nwl.cc> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
On parsing malformed X.25 facilities, decrementing the remaining length
may cause it to underflow. Since the length is an unsigned integer,
this will result in the loop continuing until the kernel crashes.
This patch adds checks to ensure decrementing the remaining length does
not cause it to wrap around.
Signed-off-by: Dan Rosenberg <drosenberg@vsecurity.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
The FBIOGET_VBLANK device ioctl allows unprivileged users to read 16
bytes of uninitialized stack memory, because the "reserved" member of
the fb_vblank struct declared on the stack is not altered or zeroed
before being copied back to the user. This patch takes care of it.
Signed-off-by: Dan Rosenberg <dan.j.rosenberg@gmail.com> Signed-off-by: Andy Walls <awalls@md.metrocast.net> Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Reported-by: Dan Rosenberg <drosenberg@vsecurity.com> Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net> CC: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-of-by: Andrew Hendry <andrew.hendry@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Dmitry Torokhov [Thu, 4 Nov 2010 16:12:44 +0000 (09:12 -0700)]
Input: i8042 - add Sony VAIO VPCZ122GX to nomux list
[Note that the mainline will not have this particular fix but rather
will blacklist entire VAIO line based off DMI board name. For stable
I am being a bit more cautious and blacklist one particular product.]
Trying to query/activate active multiplexing mode on this VAIO makes
both keyboard and touchpad inoperable. Futher kernels will blacklist
entire VAIO line, however here we blacklist just one particular model.
Enable the EFI framebuffer on 14 more Macs, including the iMac11,1
iMac10,1 iMac8,1 Macmini3,1 Macmini4,1 MacBook5,1 MacBook6,1 MacBook7,1
MacBookPro2,2 MacBookPro5,2 MacBookPro5,3 MacBookPro6,1 MacBookPro6,2 and
MacBookPro7,1
Information gathered from various user submissions.
[akpm@linux-foundation.org: coding-style fixes] Signed-off-by: Luke Macken <lmacken@redhat.com> Signed-off-by: Peter Jones <pjones@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Explicitly clear the "in-syscall" bit when we have no signal
handler and back up the program counters to back up the system
call.
Reported-by: Al Viro <viro@ZenIV.linux.org.uk> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Don't invoke the signal handler tracehook in that situation
either.
Reported-by: Al Viro <viro@ZenIV.linux.org.uk> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
If another cpu does a very wide munmap() on the signal frame area,
it can tear down the page table hierarchy from underneath us.
Borrow an idea from the 64-bit fault path's get_user_insn(), and
disable cross call interrupts during the page table traversal
to lock them in place while we operate.
Reported-by: Al Viro <viro@ZenIV.linux.org.uk> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
projects / karo-tx-linux.git / log