David Holmes found a bug in the -rt tree with respect to
pthread_cond_timedwait. After trying his test program on the latest git
from mainline, I found the bug was there too. The bug he was seeing
that his test program showed, was that if one were to do a "Ctrl-Z" on a
process that was in the pthread_cond_timedwait, and then did a "bg" on
that process, it would return with a "-ETIMEDOUT" but early. That is,
the timer would go off early.
Looking into this, I found the source of the problem. And it is a rather
nasty bug at that.
Here's the relevant code from kernel/futex.c: (not in order in the file)
[...]
smlinkage long sys_futex(u32 __user *uaddr, int op, u32 val,
struct timespec __user *utime, u32 __user *uaddr2,
u32 val3)
{
struct timespec ts;
ktime_t t, *tp = NULL;
u32 val2 = 0;
int cmd = op & FUTEX_CMD_MASK;
if (utime && (cmd == FUTEX_WAIT || cmd == FUTEX_LOCK_PI)) {
if (copy_from_user(&ts, utime, sizeof(ts)) != 0)
return -EFAULT;
if (!timespec_valid(&ts))
return -EINVAL;
t = timespec_to_ktime(ts);
if (cmd == FUTEX_WAIT)
t = ktime_add(ktime_get(), t);
tp = &t;
}
[...]
return do_futex(uaddr, op, val, tp, uaddr2, val2, val3);
}
[...]
long do_futex(u32 __user *uaddr, int op, u32 val, ktime_t *timeout,
u32 __user *uaddr2, u32 val2, u32 val3)
{
int ret;
int cmd = op & FUTEX_CMD_MASK;
struct rw_semaphore *fshared = NULL;
if (!(op & FUTEX_PRIVATE_FLAG))
fshared = ¤t->mm->mmap_sem;
switch (cmd) {
case FUTEX_WAIT:
ret = futex_wait(uaddr, fshared, val, timeout);
[...]
static int futex_wait(u32 __user *uaddr, struct rw_semaphore *fshared,
u32 val, ktime_t *abs_time)
{
[...]
struct restart_block *restart;
restart = ¤t_thread_info()->restart_block;
restart->fn = futex_wait_restart;
restart->arg0 = (unsigned long)uaddr;
restart->arg1 = (unsigned long)val;
restart->arg2 = (unsigned long)abs_time;
restart->arg3 = 0;
if (fshared)
restart->arg3 |= ARG3_SHARED;
return -ERESTART_RESTARTBLOCK;
[...]
static long futex_wait_restart(struct restart_block *restart)
{
u32 __user *uaddr = (u32 __user *)restart->arg0;
u32 val = (u32)restart->arg1;
ktime_t *abs_time = (ktime_t *)restart->arg2;
struct rw_semaphore *fshared = NULL;
restart->fn = do_no_restart_syscall;
if (restart->arg3 & ARG3_SHARED)
fshared = ¤t->mm->mmap_sem;
return (long)futex_wait(uaddr, fshared, val, abs_time);
}
So when the futex_wait is interrupt by a signal we break out of the
hrtimer code and set up or return from signal. This code does not return
back to userspace, so we set up a RESTARTBLOCK. The bug here is that we
save the "abs_time" which is a pointer to the stack variable "ktime_t t"
from sys_futex.
This returns and unwinds the stack before we get to call our signal. On
return from the signal we go to futex_wait_restart, where we update all
the parameters for futex_wait and call it. But here we have a problem
where abs_time is no longer valid.
I verified this with print statements, and sure enough, what abs_time
was set to ends up being garbage when we get to futex_wait_restart.
The solution I did to solve this (with input from Linus Torvalds)
was to add unions to the restart_block to allow system calls to
use the restart with specific parameters. This way the futex code now
saves the time in a 64bit value in the restart block instead of storing
it on the stack.
Note: I'm a bit nervious to add "linux/types.h" and use u32 and u64
in thread_info.h, when there's a #ifdef __KERNEL__ just below that.
Not sure what that is there for. If this turns out to be a problem, I've
tested this with using "unsigned int" for u32 and "unsigned long long" for
u64 and it worked just the same. I'm using u32 and u64 just to be
consistent with what the futex code uses.
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
There should be an of_node_put when breaking out of a loop that iterates
using for_each_node_by_type.
Signed-off-by: Julia Lawall <julia@diku.dk>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch adds checking for possible NULL pointer dereference
if of_find_property() failed.
Signed-off-by: Cyrill Gorcunov <gorcunov@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
There should be a pci_dev_put when breaking out of a loop that iterates
over calls to pci_get_device and similar functions.
Signed-off-by: Julia Lawall <julia@diku.dk>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add a field to the lro_mgr struct so that drivers can specify how much
padding is required to align layer 3 headers when a packet is copied
into a freshly allocated skb by inet_lro.c:lro_gen_skb(). Without
padding, skbs generated by LRO will cause alignment warnings on
architectures which require strict alignment (seen on sparc64).
Myri10GE is updated to use this field.
Signed-off-by: Andrew Gallatin <gallatin@myri.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The comment in tcp_nagle_test suggests that. This bug is very
very old, even 2.4.0 seems to have it.
Signed-off-by: Ilpo Jrvinen <ilpo.jarvinen@helsinki.fi>
Signed-off-by: David S. Miller <davem@davemloft.net>
The previous location is after sacktag processing, which affects
counters tcp_packets_in_flight depends on. This may manifest as
wrong behavior if new SACK blocks are present and all is clear
for call to tcp_cong_avoid, which in the case of
tcp_reno_cong_avoid bails out early because it thinks that
TCP is not limited by cwnd.
Signed-off-by: Ilpo Jrvinen <ilpo.jarvinen@helsinki.fi>
Signed-off-by: David S. Miller <davem@davemloft.net>
Though there's little need for everything that tcp_may_send_now
does (actually, even the state had to be adjusted to pass some
checks FRTO does not want to occur), it's more robust to let it
make the decision if sending is allowed. State adjustments
needed:
- Make sure snd_cwnd limit is not hit in there
- Disable nagle (if necessary) through the frto_counter == 2
The result of check for frto_counter in argument to call for
tcp_enter_frto_loss can just be open coded, therefore there
isn't need to store the previous frto_counter past
tcp_may_send_now.
In addition, returns can then be combined.
Signed-off-by: Ilpo Jrvinen <ilpo.jarvinen@helsinki.fi>
Signed-off-by: David S. Miller <davem@davemloft.net>
The function in question is called only from ircomm_tty_read_proc,
which is under this option. Move this helper to the same place.
Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
The rose_rebuild_header() consists only of some variables in
case INET=n, and gcc will warn us about it.
Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
The register_ip_vs_scheduler() checks for the scheduler with the
same name under the read-locked __ip_vs_sched_lock, then drops,
takes it for writing and puts the scheduler in list.
This is racy, since we can have a race window between the lock
being re-locked for writing.
The fix is to search the scheduler with the given name right under
the write-locked __ip_vs_sched_lock.
Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Acked-by: Simon Horman <horms@verge.net.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
In case we load lblc or lblcr module we can leak some sysctl
tables if the call to register_ip_vs_scheduler() fails.
I've looked at the register_ip_vs_scheduler() code and saw, that
the only reason to fail is the name collision, so I think that
with some 3rd party schedulers this becomes a relevant issue. No?
Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Acked-by: Simon Horman <horms@verge.net.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
Given a specifically crafted binary do_brk() can be used to get low
pages available in userspace virtually memory and can thus be used to
circumvent the mmap_min_addr low memory protection. Add security checks
in do_brk().
Signed-off-by: Eric Paris <eparis@redhat.com>
Acked-by: Alan Cox <alan@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
If mmap_min_addr is set and a process attempts to mmap (not fixed) with a
non-null hint address less than mmap_min_addr the mapping will fail the
security checks. Since this is just a hint address this patch will round
such a hint address above mmap_min_addr.
gcj was found to try to be very frugal with vm usage and give hint addresses
in the 8k-32k range. Without this patch all such programs failed and with
the patch they happily get a higher address.
This patch is wrappad in CONFIG_SECURITY since mmap_min_addr doesn't exist
without it and there would be no security check possible no matter what. So
we should not bother compiling in this rounding if it is just a waste of
time.
Signed-off-by: Eric Paris <eparis@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
Add security checks to make sure we are not attempting to expand the
stack into memory protected by mmap_min_addr
Signed-off-by: Eric Paris <eparis@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
On a kernel with CONFIG_SECURITY but without an LSM which implements
security_file_mmap it is impossible for an application to mmap addresses
lower than mmap_min_addr. Based on a suggestion from a developer in the
openwall community this patch adds a check for CAP_SYS_RAWIO. It is
assumed that any process with this capability can harm the system a lot
more easily than writing some stuff on the zero page and then trying to
get the kernel to trip over itself. It also means that programs like X
on i686 which use vm86 emulation can work even with mmap_min_addr set.
Signed-off-by: Eric Paris <eparis@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
Instead of using f_op to detect dead booleans, check the inode index
against the number of booleans and check the dentry name against the
boolean name for that index on reads and writes. This prevents
incorrect use of a boolean file opened prior to a policy reload while
allowing valid use of it as long as it still corresponds to the same
boolean in the policy.
Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: James Morris <jmorris@namei.org>
Do not clear f_op when removing entries since it isn't safe to do.
Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: James Morris <jmorris@namei.org>
Lately I've got this nice badness on mdio bus removal:
Device 'e0103120:06' does not have a release() function, it is broken and must be fixed.
------------[ cut here ]------------
Badness at drivers/base/core.c:107
NIP: c015c1a8 LR: c015c1a8 CTR: c0157488
REGS: c34bdcf0 TRAP: 0700 Not tainted (2.6.23-rc5-g9ebadfbb-dirty)
MSR: 00029032 <EE,ME,IR,DR> CR: 24088422 XER: 00000000
...
[c34bdda0] [c015c1a8] device_release+0x78/0x80 (unreliable)
[c34bddb0] [c01354cc] kobject_cleanup+0x80/0xbc
[c34bddd0] [c01365f0] kref_put+0x54/0x6c
[c34bdde0] [c013543c] kobject_put+0x24/0x34
[c34bddf0] [c015c384] put_device+0x1c/0x2c
[c34bde00] [c0180e84] mdiobus_unregister+0x2c/0x58
...
Though actually there is nothing broken, it just device
subsystem core expects another "pattern" of resource managment.
This patch implement phy device's release function, thus
we're getting rid of this badness.
Also small hidden bug fixed, hope none other introduced. ;-)
Signed-off-by: Anton Vorontsov <avorontsov@ru.mvista.com>
Acked-by: Andy Fleming <afleming@freescale.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Eliminate an uninitialized variable warning. The code is correct, but
a pointer to the automatic variable 'addr' is passed to dma_alloc_coherent.
Since addr has never been initialized, and the compiler doesn't know
what dma_alloc_coherent will do with it, it complains.
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Turns out we're freeing the skb when we detect CRC error, but we're
not clearing out info->skb. We could either clear it and have the stack
reallocate it, or just leave it and the rx ring refill code will reuse
the one that was allocated.
Reusing a freed skb obviously caused some nasty crashes of various kind,
as reported by Brent Baude and David Woodhouse.
Signed-off-by: Olof Johansson <olof@lixom.net>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Prevent deadlock in sky2 recovery logic. sky2_down calls napi_synchronize
which gets stuck if napi was already disabled.
Fix by rearranging slightly and not calling napi_disable until after
both ports are stopped. The napi_disable probably is being overly
paranoid, but it is safe now.
Signed-off-by: Stephen Hemminger <shemminger@linux-foundation.org>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
The mpc5200 fec driver is corrupting memory. This patch fixes two bugs
where the wrong skb was being referenced.
Signed-off-by: Jon Smirl <jonsmirl@gmail.com>
Acked-by: Domen Puncer <domen.puncer@telargo.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Signed-off-by: David Woodhouse <dwmw2@infradead.org>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
* Don't program UDMA timings when programming PIO or MWDMA modes.
This has also a nice side-effect of fixing regression added by commit
681c80b5d9 ("libata: correct handling of
SRST reset sequences") (->set_piomode method for PIO0 is called before
->cable_detect method which checks UDMA timings to get the cable type).
* Bump driver version.
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
Tested-by: "Thomas Lindroth" <thomas.lindroth@gmail.com>
Acked-by: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: Tejun Heo <htejun@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Add the device IDs of legacy mode of MCP79 AHCI controller to ahci.c
Signed-off-by: Peer Chen <peerchen@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
The Highpoint RocketRAID boards using Marvell 7042 chips
overwrite the 9th sector of attached drives at boot time,
when those drives are configured as "Legacy" (the default)
in the HighPoint BIOS.
This kills GRUB, and probably other stuff.
But it all happens *before* Linux is even loaded.
So, for now we'll log a WARNING when such boards are detected,
and advise users to configure BIOS "JBOD" volumes instead,
which don't appear to suffer from this problem.
Signed-off-by: Mark Lord <mlord@pobox.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
We need to run any DMA command with result taskfile requested in ADMA mode
when the port is in ADMA mode, otherwise it may try to use the legacy DMA engine
in ADMA mode which is not allowed. Enforce this with BUG_ON() since data
corruption could potentially result if this happened. Also, fail any attempt to
try and issue NCQ commands with result taskfile requested, since the hardware
doesn't allow this.
Signed-off-by: Robert Hancock <hancockr@shaw.ca>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
* 'for-linus' of git://git390.osdl.marist.edu/pub/scm/linux-2.6:
[S390] Make sure the restore psw masks are initialized.
[S390] Fix compile error on 31bit without preemption
[S390] dcssblk: prevent early access without own make_request function
[S390] cio: add missing reprobe loop end statement
[S390] cio: Issue SenseID per path.
* git://git.kernel.org/pub/scm/linux/kernel/git/mingo/linux-2.6-sched:
sched: default to more agressive yield for SCHED_BATCH tasks
sched: fix crash in sys_sched_rr_get_interval()
I haven't seen Richard doing MTRR related work for quite some time, and
the "X86 ARCHITECTURE" entry in MAINTAINERS already covers the people
currently responsible for this code.
Signed-off-by: Adrian Bunk <bunk@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
fix this on i386 allnoconfig:
WARNING: vmlinux.o(.text+0x6f2e): Section mismatch: reference to .init.text:register_cpu (between 'arch_register_cpu' and 'text_poke')
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
free_cache_attributes() must be __cpuinit since it calls the
__cpuinit cache_remove_shared_cpu_map().
This patch fixes the following section mismatch reported by
Chris Clayton:
...
WARNING: vmlinux.o(.text+0x90b6): Section mismatch: reference to .init.text:cache_remove_shared_cpu_map (between 'free_cache_attributes' and 'show_level')
...
Signed-off-by: Adrian Bunk <bunk@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Our automated test suite looks for keywords like error, fail, warning in
the boot log. In the case when the nmi watchdog is determined to be
stuck in check_nmi_watchdog(), none of those keywords are displayed.
This patch adds a keyword, "WARNING:", so it makes it easier to notice
when the nmi watchdog isn't working correctly. Also add a proper
KERN_WARNING mark to this printout.
Signed-off-by: Don Zickus <dzickus@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
The recent Kconfig changes in x86 resulted in CONFIG_X86_HT no longer
being set if (X86_32 && MK8).
After grep'ing through the tree I think the problem is that different
places have different assumptions about the semantics of CONFIG_X86_HT,
either:
- hyperthreading or
- multicore
This should be sorted out properly, but until then we should keep the
2.6.23 status quo.
Signed-off-by: Adrian Bunk <bunk@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
do more agressive yield for SCHED_BATCH tuned tasks: they are all
about throughput anyway. This allows a gentler migration path for
any apps that relied on stronger yield.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Luiz Fernando N. Capitulino reported that sched_rr_get_interval()
crashes for SCHED_OTHER tasks that are on an idle runqueue.
The fix is to return a 0 timeslice for tasks that are on an idle
runqueue. (and which are not running, obviously)
this also shrinks the code a bit:
text data bss dec hex filename
47903 3934 336 52173 cbcd sched.o.before
47885 3934 336 52155 cbbb sched.o.after
Reported-by: Luiz Fernando N. Capitulino <lcapitulino@mandriva.com.br>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
In case of TRACE_IRQFLAGS the restore psw masks will not be
initialized if noexec is turned on. This will lead to an
immediate system crash.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Commit b8e7a54cd0 introduced a compile
error if CONFIG_PREEMPT is not set:
arch/s390/kernel/built-in.o: In function `cleanup_io_leave_insn':
/space/kvm/arch/s390/kernel/entry.S:(.text+0xbfce): undefined reference to `preempt_schedule_irq'
This patch hides preempt_schedule_irq if CONFIG_PREEMPT is not set.
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Steven Rostedt
David S. Miller
Julia Lawall
Cyrill Gorcunov
Joe Perches
Andrew Gallatin
Ilpo Jrvinen
Pavel Emelyanov
Eric Paris
Stephen Smalley
Paul Mackerras
Linus Torvalds
Anton Vorontsov
Grant Likely
Olof Johansson
Wang Chen
Stephen Hemminger
Jon Smirl
David Woodhouse
Divy Le Ray
Bartlomiej Zolnierkiewicz
peerchen
Mark Lord
Robert Hancock
Adrian Bunk
Ingo Molnar
Andrew Morton
Don Zickus
Heiko Carstens
Christian Borntraeger