commit fb3d85bc71 upstream.
The xhci_save_registers() function saved the event ring dequeue pointer
in the s3 register structure, but xhci_restore_registers() never
restored it. No other code in the xHCI successful resume path would
ever restore it either. Fix that.
This should be backported to kernels as old as 2.6.37, that contain the
commit 5535b1d5f8 "USB: xHCI: PCI power
management implementation".
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Tested-by: Elric Fu <elricfu1@gmail.com>
Cc: Andiry Xu <andiry.xu@amd.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 159e1fcc9a upstream.
When xhci_mem_cleanup() is called, we can't be sure if the xHC is
actually halted. We can ask the xHC to halt by writing to the RUN bit
in the command register, but that might timeout due to a HW hang.
If the host controller is still running, we should not write zeroed
values to the event ring dequeue pointers or base tables, the DCBAA
pointers, or the command ring pointers. Eric Fu reports his VIA VL800
host accesses the event ring pointers after a failed register restore on
resume from suspend. The hypothesis is that the host never actually
halted before the register write to change the event ring pointer to
zero.
Remove all writes of zeroed values to pointer registers in
xhci_mem_cleanup(). Instead, make all callers of the function reset the
host controller first, which will reset those registers to zero.
xhci_mem_init() is the only caller that doesn't first halt and reset the
host controller before calling xhci_mem_cleanup().
This should be backported to kernels as old as 2.6.32.
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Tested-by: Elric Fu <elricfu1@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 4e833c0b87 upstream.
While we're at that, define IMAN bitfield to aid readability.
The interrupt enable bit should be set once on driver init, and we
shouldn't need to continually re-enable it. Commit c21599a3 introduced
a read of the irq_pending register, and that allows us to preserve the
state of the IE bit. Before that commit, we were blindly writing 0x3 to
the register.
This patch should be backported to kernels as old as 2.6.36, or ones
that contain the commit c21599a361 "USB:
xhci: Reduce reads and writes of interrupter registers".
Signed-off-by: Felipe Balbi <balbi@ti.com>
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit bcf3985376 upstream.
This patch (as1517b) fixes an error in the USB scatter-gather library.
The library code uses urb->dev to determine whether or nor an URB is
currently active; the completion handler sets urb->dev to NULL.
However the core unlinking routines need to use urb->dev. Since
unlinking always racing with completion, the completion handler must
not clear urb->dev -- it can lead to invalid memory accesses when a
transfer has to be cancelled.
This patch fixes the problem by getting rid of the lines that clear
urb->dev after urb has been submitted. As a result we may end up
trying to unlink an URB that failed in submission or that has already
completed, so an extra check is added after each unlink to avoid
printing an error message when this happens. The checks are updated
in both sg_complete() and sg_cancel(), and the second is updated to
match the first (currently it prints out unnecessary warning messages
if a device is unplugged while a transfer is in progress).
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Reported-and-tested-by: Illia Zaitsev <I.Zaitsev@adbglobal.com>
CC: Ming Lei <tom.leiming@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit ce5c985185 upstream.
DTR/RTS should only be raised when changing baudrate from B0 and not on
any baud rate change (> B0).
Reported-by: Søren Holm <sgh@sgh.dk>
Signed-off-by: Johan Hovold <jhovold@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 6f103929f8 upstream.
Fix tick_nohz_restart() to not use a stale ktime_t "now" value when
calling tick_do_update_jiffies64(now).
If we reach this point in the loop it means that we crossed a tick
boundary since we grabbed the "now" timestamp, so at this point "now"
refers to a time in the old jiffy, so using the old value for "now" is
incorrect, and is likely to give us a stale jiffies value.
In particular, the first time through the loop the
tick_do_update_jiffies64(now) call is always a no-op, since the
caller, tick_nohz_restart_sched_tick(), will have already called
tick_do_update_jiffies64(now) with that "now" value.
Note that tick_nohz_stop_sched_tick() already uses the correct
approach: when we notice we cross a jiffy boundary, grab a new
timestamp with ktime_get(), and *then* update jiffies.
Signed-off-by: Neal Cardwell <ncardwell@google.com>
Cc: Ben Segall <bsegall@google.com>
Cc: Ingo Molnar <mingo@elte.hu>
Link: http://lkml.kernel.org/r/1332875377-23014-1-git-send-email-ncardwell@google.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 63fa471dd4 upstream.
When a process exec()'s, all the maps are retired, but we keep the hist
entries around which hold references to those outdated maps.
If the same library gets mapped in for which we have hist entries, a new
map will be created. But when we take a perf entry hit within that map,
we'll find the existing hist entry with the older map.
This causes symbol translations to be done incorrectly. For example,
the perf entry processing will lookup the correct uptodate map entry and
use that to calculate the symbol and DSO relative address. But later
when we update the histogram we'll translate the address using the
outdated map file instead leading to conditions such as out-of-range
offsets in symbol__inc_addr_samples().
Therefore, update the map of the hist_entry dynamically at lookup/
creation time.
Signed-off-by: David S. Miller <davem@davemloft.net>
Link: http://lkml.kernel.org/r/20120327.031418.1220315351537060808.davem@davemloft.net
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit bc67f63650 upstream.
The total number of scatter gather elements in the CISS command
used by the scsi tape code was being cast to a u8, which can hold
at most 255 scatter gather elements. It should have been cast to
a u16. Without this patch the command gets rejected by the controller
since the total scatter gather count did not add up to the right
value resulting in an i/o error.
Signed-off-by: Stephen M. Cameron <scameron@beardog.cce.hp.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 395d287526 upstream.
The default is too small (1024 blocks), use h->cciss_max_sectors (8192 blocks)
Without this change, if you try to set the block size of a tape drive above
512*1024, via "mt -f /dev/st0 setblk nnn" where nnn is greater than 524288,
it won't work right.
Signed-off-by: Stephen M. Cameron <scameron@beardog.cce.hp.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 9e0daff30f upstream.
The DS driver registers as a subsys_initcall() but this can be too
early, in particular this risks registering before we've had a chance
to allocate and setup module_kset in kernel/params.c which is
performed also as a subsyts_initcall().
Register DS using device_initcall() insteal.
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 3d3eeb2ef2 upstream.
The invocation of softirq is now handled by irq_exit(), so there is no
need for sparc64 to invoke it on the trap-return path. In fact, doing so
is a bug because if the trap occurred in the idle loop, this invocation
can result in lockdep-RCU failures. The problem is that RCU ignores idle
CPUs, and the sparc64 trap-return path to the softirq handlers fails to
tell RCU that the CPU must be considered non-idle while those handlers
are executing. This means that RCU is ignoring any RCU read-side critical
sections in those handlers, which in turn means that RCU-protected data
can be yanked out from under those read-side critical sections.
The shiny new lockdep-RCU ability to detect RCU read-side critical sections
that RCU is ignoring located this problem.
The fix is straightforward: Make sparc64 stop manually invoking the
softirq handlers.
Reported-by: Meelis Roos <mroos@linux.ee>
Suggested-by: David Miller <davem@davemloft.net>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Tested-by: Meelis Roos <mroos@linux.ee>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 66aebce747 upstream.
The race is as follows:
Suppose a multi-threaded task forks a new process (on cpu A), thus
bumping up the ref count on all the pages. While the fork is occurring
(and thus we have marked all the PTEs as read-only), another thread in
the original process (on cpu B) tries to write to a huge page, taking an
access violation from the write-protect and calling hugetlb_cow(). Now,
suppose the fork() fails. It will undo the COW and decrement the ref
count on the pages, so the ref count on the huge page drops back to 1.
Meanwhile hugetlb_cow() also decrements the ref count by one on the
original page, since the original address space doesn't need it any
more, having copied a new page to replace the original page. This
leaves the ref count at zero, and when we call unlock_page(), we panic.
fork on CPU A fault on CPU B
============= ==============
...
down_write(&parent->mmap_sem);
down_write_nested(&child->mmap_sem);
...
while duplicating vmas
if error
break;
...
up_write(&child->mmap_sem);
up_write(&parent->mmap_sem); ...
down_read(&parent->mmap_sem);
...
lock_page(page);
handle COW
page_mapcount(old_page) == 2
alloc and prepare new_page
...
handle error
page_remove_rmap(page);
put_page(page);
...
fold new_page into pte
page_remove_rmap(page);
put_page(page);
...
oops ==> unlock_page(page);
up_read(&parent->mmap_sem);
The solution is to take an extra reference to the page while we are
holding the lock on it.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
Cc: Hillf Danton <dhillf@gmail.com>
Cc: Michal Hocko <mhocko@suse.cz>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Hugh Dickins <hughd@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit c76f39bddb upstream.
Michel Lespinasse cleaned up the futex calling conventions in commit
37a9d912b2 ("futex: Sanitize cmpxchg_futex_value_locked API").
But the ia64 implementation was subtly broken. Gcc does not know that
register "r8" will be updated by the fault handler if the cmpxchg
instruction takes an exception. So it feels safe in letting the
initialization of r8 slide to after the cmpxchg. Result: we always
return 0 whether the user address faulted or not.
Fix by moving the initialization of r8 into the __asm__ code so gcc
won't move it.
Reported-by: <emeric.maschino@gmail.com>
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=42757
Tested-by: <emeric.maschino@gmail.com>
Acked-by: Michel Lespinasse <walken@google.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This is a partial, self-contained, minimal backport of commit
797fe796c4 upstream which fixes the memory
leak:
Bluetooth: uart-ldisc: Fix memory leak and remove destruct cb
We currently leak the hci_uart object if HCI_UART_PROTO_SET is never set
because the hci-destruct callback will then never be called. This fix
removes the hci-destruct callback and frees the driver internal private
hci_uart object directly on tty-close. We call hci_unregister_dev() here
so the hci-core will never call our callbacks again (except destruct).
Therefore, we can safely free the driver internal data right away and
set the destruct callback to NULL.
Signed-off-by: David Herrmann <dh.herrmann@googlemail.com>
Acked-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Johan Hovold <jhovold@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 078c04545b upstream.
Currently when ThumbEE is not enabled (!CONFIG_ARM_THUMBEE) the ThumbEE
register states are not saved/restored at context switch. The default state
of the ThumbEE Ctrl register (TEECR) allows userspace accesses to the
ThumbEE Base Handler register (TEEHBR). This can cause unexpected behaviour
when people use ThumbEE on !CONFIG_ARM_THUMBEE kernels, as well as allowing
covert communication - eg between userspace tasks running inside chroot
jails.
This patch sets up TEECR in order to prevent user-space access to TEEHBR
when !CONFIG_ARM_THUMBEE. In this case, tasks are sent SIGILL if they try to
access TEEHBR.
Reviewed-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Jonathan Austin <jonathan.austin@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 27c1cbd06a upstream.
The 845g shares the errata with i830 whereby executing a command
within 2 cachelines of the end of the ringbuffer may cause a GPU hang.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 18daf1644e upstream
Commit 330605423c fixed l2cap conn establishment for non-ssp remote
devices by not setting HCI_CONN_ENCRYPT_PEND every time conn security
is tested (which was always returning failure on any subsequent
security checks).
However, this broke l2cap conn establishment for ssp remote devices
when an ACL link was already established at SDP-level security. This
fix ensures that encryption must be pending whenever authentication
is also pending.
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Tested-by: Daniel Wagner <daniel.wagner@bmw-carit.de>
Acked-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
commit df91e49477 upstream.
Userspace can pass in arbitrary combinations of MS_* flags to mount().
If both MS_BIND and one of MS_SHARED/MS_PRIVATE/MS_SLAVE/MS_UNBINDABLE are
passed, device name which should be checked for MS_BIND was not checked because
MS_SHARED/MS_PRIVATE/MS_SLAVE/MS_UNBINDABLE had higher priority than MS_BIND.
If both one of MS_BIND/MS_MOVE and MS_REMOUNT are passed, device name which
should not be checked for MS_REMOUNT was checked because MS_BIND/MS_MOVE had
higher priority than MS_REMOUNT.
Fix these bugs by changing priority to MS_REMOUNT -> MS_BIND ->
MS_SHARED/MS_PRIVATE/MS_SLAVE/MS_UNBINDABLE -> MS_MOVE as with do_mount() does.
Also, unconditionally return -EINVAL if more than one of
MS_SHARED/MS_PRIVATE/MS_SLAVE/MS_UNBINDABLE is passed so that TOMOYO will not
generate inaccurate audit logs, for commit 7a2e8a8f "VFS: Sanity check mount
flags passed to change_mnt_propagation()" clarified that these flags must be
exclusively passed.
Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: James Morris <james.l.morris@oracle.com>
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 9ddd592a19 upstream.
Unfortunatly the interrupts for the event log and the
peripheral page-faults are only enabled at boot but not
re-enabled at resume. Fix that.
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
[bwh: Backport to 3.0:
- Drop change to PPR log which was added in 3.3
- Source is under arch/x86/kernel]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 79549c6dfd upstream.
keyctl_session_to_parent(task) sets ->replacement_session_keyring,
it should be processed and cleared by key_replace_session_keyring().
However, this task can fork before it notices TIF_NOTIFY_RESUME and
the new child gets the bogus ->replacement_session_keyring copied by
dup_task_struct(). This is obviously wrong and, if nothing else, this
leads to put_cred(already_freed_cred).
change copy_creds() to clear this member. If copy_process() fails
before this point the wrong ->replacement_session_keyring doesn't
matter, exit_creds() won't be called.
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit a2daf26310 upstream.
Added Vendor/Device Id of Motorola Rokr E6 (22b8:6027) so it can be
recognized by the "zaurus" USBNet driver.
Applies to Linux 3.2.13 and 2.6.39.4.
Signed-off-by: Guan Xin <guanx.bac@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 3f8349e6e9 upstream.
TWL6030 family of PMIC use a shadow interrupt status register
while kernel processes the current interrupt event.
However, any write(0 or 1) to register INT_STS_A, INT_STS_B or
INT_STS_C clears all 3 interrupt status registers.
Since clear of the interrupt is done on 32k clk, depending on I2C
bus speed, we could in-adverently clear the status of a interrupt
status pending on shadow register in the current implementation.
This is due to the fact that multi-byte i2c write operation into
three seperate status register could result in multiple load
and clear of status and result in lost interrupts.
Instead, doing a single byte write to INT_STS_A register with 0x0
will clear all three interrupt status registers without the related
risk.
Acked-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Signed-off-by: Nishanth Menon <nm@ti.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 9993bc635d upstream.
When a machine boots up, the TSC generally gets reset. However,
when kexec is used to boot into a kernel, the TSC value would be
carried over from the previous kernel. The computation of
cycns_offset in set_cyc2ns_scale is prone to an overflow, if the
machine has been up more than 208 days prior to the kexec. The
overflow happens when we multiply *scale, even though there is
enough room to store the final answer.
We fix this issue by decomposing tsc_now into the quotient and
remainder of division by CYC2NS_SCALE_FACTOR and then performing
the multiplication separately on the two components.
Refactor code to share the calculation with the previous
fix in __cycles_2_ns().
Signed-off-by: Salman Qazi <sqazi@google.com>
Acked-by: John Stultz <john.stultz@linaro.org>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Turner <pjt@google.com>
Cc: john stultz <johnstul@us.ibm.com>
Link: http://lkml.kernel.org/r/20120310004027.19291.88460.stgit@dungbeetle.mtv.corp.google.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Cc: Mike Galbraith <efault@gmx.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit a97f4f5e52 upstream.
Carlos was getting
WARNING: at drivers/pci/pci.c:118 pci_ioremap_bar+0x24/0x52()
when probing his sound card, and sound did not work. After adding
pci=use_crs to the kernel command line, no more trouble.
Ok, we can add a quirk. dmidecode output reveals that this is an MSI
MS-7253, for which we already have a quirk, but the short-sighted
author tied the quirk to a single BIOS version, making it not kick in
on Carlos's machine with BIOS V1.2. If a later BIOS update makes it
no longer necessary to look at the _CRS info it will still be
harmless, so let's stop trying to guess which versions have and don't
have accurate _CRS tables.
Addresses https://bugtrack.alsa-project.org/alsa-bug/view.php?id=5533
Also see <https://bugzilla.kernel.org/show_bug.cgi?id=42619>.
Reported-by: Carlos Luna <caralu74@gmail.com>
Reviewed-by: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 8411371709 upstream.
In the spirit of commit 29cf7a30f8 ("x86/PCI: use host bridge _CRS
info on ASUS M2V-MX SE"), this DMI quirk turns on "pci_use_crs" by
default on a board that needs it.
This fixes boot failures and oopses introduced in 3e3da00c01
("x86/pci: AMD one chain system to use pci read out res"). The quirk
is quite targetted (to a specific board and BIOS version) for two
reasons:
(1) to emphasize that this method of tackling the problem one quirk
at a time is a little insane
(2) to give BIOS vendors an opportunity to use simpler tables and
allow us to return to generic behavior (whatever that happens to
be) with a later BIOS update
In other words, I am not at all happy with having quirks like this.
But it is even worse for the kernel not to work out of the box on
these machines, so...
Reference: https://bugzilla.kernel.org/show_bug.cgi?id=42619
Reported-by: Svante Signell <svante.signell@telia.com>
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 258f742635 upstream.
Commit f02e8a6596 ("module: Sort exported symbols") sorts symbols
placing each of them in its own elf section. This sorting and merging
into the canonical sections are done by the linker.
Unfortunately modpost to generate Module.symvers file parses vmlinux.o
(which is not linked yet) and all modules object files (which aren't
linked yet). These aren't sanitized by the linker yet. That breaks
modpost that can't detect license properly for modules.
This patch makes modpost aware of the new exported symbols structure.
[ This above is a slightly corrected version of the explanation of the
problem, copied from commit 62a2635610 ("modpost: Fix modpost's
license checking V3"). That commit fixed the problem for module
object files, but not for vmlinux.o. This patch fixes modpost for
vmlinux.o. ]
Signed-off-by: Frank Rowand <frank.rowand@am.sony.com>
Signed-off-by: Alessio Igor Bogani <abogani@kernel.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 62a2635610 upstream.
The commit f02e8a6 sorts symbols placing each of them in its own elf section.
The sorting and merging into the canonical sections are done by the linker.
Unfortunately modpost to generate Module.symvers file parses vmlinux
(already linked) and all modules object files (which aren't linked yet).
These aren't sanitized by the linker yet. That breaks modpost that can't
detect license properly for modules. This patch makes modpost aware of
the new exported symbols structure.
Thanks to Arnaud Lacombe <lacombar@gmail.com> and Anders Kaseorg
<andersk@ksplice.com> for providing useful suggestions about code.
This work was supported by a hardware donation from the CE Linux Forum.
Reported-by: Jan Beulich <jbeulich@novell.com>
Signed-off-by: Alessio Igor Bogani <abogani@kernel.org>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 620f6e8e85 upstream.
Commit bfdc0b4 adds code to restrict access to dmesg_restrict,
however, it incorrectly alters kptr_restrict rather than
dmesg_restrict.
The original patch from Richard Weinberger
(https://lkml.org/lkml/2011/3/14/362) alters dmesg_restrict as
expected, and so the patch seems to have been misapplied.
This adds the CAP_SYS_ADMIN check to both dmesg_restrict and
kptr_restrict, since both are sensitive.
Reported-by: Phillip Lougher <plougher@redhat.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Acked-by: Serge Hallyn <serge.hallyn@canonical.com>
Acked-by: Richard Weinberger <richard@nod.at>
Signed-off-by: James Morris <james.l.morris@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 3751d3e85c upstream.
There has long been a limitation using software breakpoints with a
kernel compiled with CONFIG_DEBUG_RODATA going back to 2.6.26. For
this particular patch, it will apply cleanly and has been tested all
the way back to 2.6.36.
The kprobes code uses the text_poke() function which accommodates
writing a breakpoint into a read-only page. The x86 kgdb code can
solve the problem similarly by overriding the default breakpoint
set/remove routines and using text_poke() directly.
The x86 kgdb code will first attempt to use the traditional
probe_kernel_write(), and next try using a the text_poke() function.
The break point install method is tracked such that the correct break
point removal routine will get called later on.
Cc: x86@kernel.org
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Inspried-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 23bbd8e346 upstream.
The do_fork and sys_open tests have never worked properly on anything
other than a UP configuration with the kgdb test suite. This is
because the test suite did not fully implement the behavior of a real
debugger. A real debugger tracks the state of what thread it asked to
single step and can correctly continue other threads of execution or
conditionally stop while waiting for the original thread single step
request to return.
Below is a simple method to cause a fatal kernel oops with the kgdb
test suite on a 2 processor ARM system:
while [ 1 ] ; do ls > /dev/null 2> /dev/null; done&
while [ 1 ] ; do ls > /dev/null 2> /dev/null; done&
echo V1I1F100 > /sys/module/kgdbts/parameters/kgdbts
Very soon after starting the test the kernel will start warning with
messages like:
kgdbts: BP mismatch c002487c expected c0024878
------------[ cut here ]------------
WARNING: at drivers/misc/kgdbts.c:317 check_and_rewind_pc+0x9c/0xc4()
[<c01f6520>] (check_and_rewind_pc+0x9c/0xc4)
[<c01f595c>] (validate_simple_test+0x3c/0xc4)
[<c01f60d4>] (run_simple_test+0x1e8/0x274)
The kernel will eventually recovers, but the test suite has completely
failed to test anything useful.
This patch implements behavior similar to a real debugger that does
not rely on hardware single stepping by using only software planted
breakpoints.
In order to mimic a real debugger, the kgdb test suite now tracks the
most recent thread that was continued (cont_thread_id), with the
intent to single step just this thread. When the response to the
single step request stops in a different thread that hit the original
break point that thread will now get continued, while the debugger
waits for the thread with the single step pending. Here is a high
level description of the sequence of events.
cont_instead_of_sstep = 0;
1) set breakpoint at do_fork
2) continue
3) Save the thread id where we stop to cont_thread_id
4) Remove breakpoint at do_fork
5) Reset the PC if needed depending on kernel exception type
6) soft single step
7) Check where we stopped
if current thread != cont_thread_id {
if (here for more than 2 times for the same thead) {
### must be a really busy system, start test again ###
goto step 1
}
goto step 5
} else {
cont_instead_of_sstep = 0;
}
8) clean up and run test again if needed
9) Clear out any threads that were waiting on a break point at the
point in time the test is ended with get_cont_catch(). This
happens sometimes because breakpoints are used in place of single
stepping and some threads could have been in the debugger exception
handling queue because breakpoints were hit concurrently on
different CPUs. This also means we wait at least one second before
unplumbing the debugger connection at the very end, so as respond
to any debug threads waiting to be serviced.
Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 486c5987a0 upstream.
The do_fork and sys_open tests have never worked properly on anything
other than a UP configuration with the kgdb test suite. This is
because the test suite did not fully implement the behavior of a real
debugger. A real debugger tracks the state of what thread it asked to
single step and can correctly continue other threads of execution or
conditionally stop while waiting for the original thread single step
request to return.
Below is a simple method to cause a fatal kernel oops with the kgdb
test suite on a 4 processor x86 system:
while [ 1 ] ; do ls > /dev/null 2> /dev/null; done&
while [ 1 ] ; do ls > /dev/null 2> /dev/null; done&
while [ 1 ] ; do ls > /dev/null 2> /dev/null; done&
while [ 1 ] ; do ls > /dev/null 2> /dev/null; done&
echo V1I1F1000 > /sys/module/kgdbts/parameters/kgdbts
Very soon after starting the test the kernel will oops with a message like:
kgdbts: BP mismatch 3b7da66480 expected ffffffff8106a590
WARNING: at drivers/misc/kgdbts.c:303 check_and_rewind_pc+0xe0/0x100()
Call Trace:
[<ffffffff812994a0>] check_and_rewind_pc+0xe0/0x100
[<ffffffff81298945>] validate_simple_test+0x25/0xc0
[<ffffffff81298f77>] run_simple_test+0x107/0x2c0
[<ffffffff81298a18>] kgdbts_put_char+0x18/0x20
The warn will turn to a hard kernel crash shortly after that because
the pc will not get properly rewound to the right value after hitting
a breakpoint leading to a hard lockup.
This change is broken up into 2 pieces because archs that have hw
single stepping (2.6.26 and up) need different changes than archs that
do not have hw single stepping (3.0 and up). This change implements
the correct behavior for an arch that supports hw single stepping.
A minor defect was fixed where sys_open should be do_sys_open
for the sys_open break point test. This solves the problem of running
a 64 bit with a 32 bit user space. The sys_open() never gets called
when using the 32 bit file system for the kgdb testsuite because the
32 bit binaries invoke the compat_sys_open() call leading to the test
never completing.
In order to mimic a real debugger, the kgdb test suite now tracks the
most recent thread that was continued (cont_thread_id), with the
intent to single step just this thread. When the response to the
single step request stops in a different thread that hit the original
break point that thread will now get continued, while the debugger
waits for the thread with the single step pending. Here is a high
level description of the sequence of events.
cont_instead_of_sstep = 0;
1) set breakpoint at do_fork
2) continue
3) Save the thread id where we stop to cont_thread_id
4) Remove breakpoint at do_fork
5) Reset the PC if needed depending on kernel exception type
6) if (cont_instead_of_sstep) { continue } else { single step }
7) Check where we stopped
if current thread != cont_thread_id {
cont_instead_of_sstep = 1;
goto step 5
} else {
cont_instead_of_sstep = 0;
}
8) clean up and run test again if needed
Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 456ca7ff24 upstream.
On x86 the kgdb test suite will oops when the kernel is compiled with
CONFIG_DEBUG_RODATA and you run the tests after boot time. This is
regression has existed since 2.6.26 by commit: b33cb815 (kgdbts: Use
HW breakpoints with CONFIG_DEBUG_RODATA).
The test suite can use hw breakpoints for all the tests, but it has to
execute the hardware breakpoint specific tests first in order to
determine that the hw breakpoints actually work. Specifically the
very first test causes an oops:
# echo V1I1 > /sys/module/kgdbts/parameters/kgdbts
kgdb: Registered I/O driver kgdbts.
kgdbts:RUN plant and detach test
Entering kdb (current=0xffff880017aa9320, pid 1078) on processor 0 due to Keyboard Entry
[0]kdb> kgdbts: ERROR PUT: end of test buffer on 'plant_and_detach_test' line 1 expected OK got $E14#aa
WARNING: at drivers/misc/kgdbts.c:730 run_simple_test+0x151/0x2c0()
[...oops clipped...]
This commit re-orders the running of the tests and puts the RODATA
check into its own function so as to correctly avoid the kernel oops
by detecting and using the hw breakpoints.
Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 98b54aa1a2 upstream.
There is extra state information that needs to be exposed in the
kgdb_bpt structure for tracking how a breakpoint was installed. The
debug_core only uses the the probe_kernel_write() to install
breakpoints, but this is not enough for all the archs. Some arch such
as x86 need to use text_poke() in order to install a breakpoint into a
read only page.
Passing the kgdb_bpt structure to kgdb_arch_set_breakpoint() and
kgdb_arch_remove_breakpoint() allows other archs to set the type
variable which indicates how the breakpoint was installed.
Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 927a2f119e upstream.
i915_drm_thaw was not locking the mode_config lock when calling
drm_helper_resume_force_mode. When there were multiple wake sources,
this caused FDI training failure on SNB which in turn corrupted the
display.
Signed-off-by: Sean Paul <seanpaul@chromium.org>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-Off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>