Commit Graph

269 Commits

Author SHA1 Message Date
Kees Cook 656de42e83 pstore: Avoid potential infinite loop
If a backend does not correctly iterate through its records, pstore will
get stuck loading entries. Detect this with a large record count, and
announce if we ever hit the limit. This will let future backend reading
bugs less annoying to debug. Additionally adjust the error about
pstore_mkfile() failing.

Signed-off-by: Kees Cook <keescook@chromium.org>
2017-05-31 10:13:42 -07:00
Douglas Anderson f6525b96dd pstore: Fix leaked pstore_record in pstore_get_backend_records()
When the "if (record->size <= 0)" test is true in
pstore_get_backend_records() it's pretty clear that nobody holds a
reference to the allocated pstore_record, yet we don't free it.

Let's free it.

Fixes: 2a2b0acf76 ("pstore: Allocate records on heap instead of stack")
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Signed-off-by: Kees Cook <keescook@chromium.org>
Cc: stable@vger.kernel.org
2017-05-31 10:10:09 -07:00
Ankit Kumar 4a16d1cb24 pstore: Don't warn if data is uncompressed and type is not PSTORE_TYPE_DMESG
commit 9abdcccc3d ("pstore: Extract common arguments into structure")
moved record decompression to function. decompress_record() gets
called without checking type and compressed flag. Warning will be
reported if data is uncompressed. Pstore type PSTORE_TYPE_PPC_OPAL,
PSTORE_TYPE_PPC_COMMON doesn't contain compressed data and warning get
printed part of dmesg.

Partial dmesg log:
[   35.848914] pstore: ignored compressed record type 6
[   35.848927] pstore: ignored compressed record type 8

Above warning should not get printed as it is known that data won't be
compressed for above type and it is valid condition.

This patch returns if data is not compressed and print warning only if
data is compressed and type is not PSTORE_TYPE_DMESG.

Reported-by: Anton Blanchard <anton@au1.ibm.com>
Signed-off-by: Ankit Kumar <ankit@linux.vnet.ibm.com>
Reviewed-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Fixes: 9abdcccc3d ("pstore: Extract common arguments into structure")
Cc: stable@vger.kernel.org
2017-05-31 10:09:32 -07:00
Linus Torvalds 291b38a756 Annotation of module parameters that specify device settings
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Merge tag 'hwparam-20170420' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs

Pull hw lockdown support from David Howells:
 "Annotation of module parameters that configure hardware resources
  including ioports, iomem addresses, irq lines and dma channels.

  This allows a future patch to prohibit the use of such module
  parameters to prevent that hardware from being abused to gain access
  to the running kernel image as part of locking the kernel down under
  UEFI secure boot conditions.

  Annotations are made by changing:

        module_param(n, t, p)
        module_param_named(n, v, t, p)
        module_param_array(n, t, m, p)

  to:

        module_param_hw(n, t, hwtype, p)
        module_param_hw_named(n, v, t, hwtype, p)
        module_param_hw_array(n, t, hwtype, m, p)

  where the module parameter refers to a hardware setting

  hwtype specifies the type of the resource being configured. This can
  be one of:

        ioport          Module parameter configures an I/O port
        iomem           Module parameter configures an I/O mem address
        ioport_or_iomem Module parameter could be either (runtime set)
        irq             Module parameter configures an I/O port
        dma             Module parameter configures a DMA channel
        dma_addr        Module parameter configures a DMA buffer address
        other           Module parameter configures some other value

  Note that the hwtype is compile checked, but not currently stored (the
  lockdown code probably won't require it). It is, however, there for
  future use.

  A bonus is that the hwtype can also be used for grepping.

  The intention is for the kernel to ignore or reject attempts to set
  annotated module parameters if lockdown is enabled. This applies to
  options passed on the boot command line, passed to insmod/modprobe or
  direct twiddling in /sys/module/ parameter files.

  The module initialisation then needs to handle the parameter not being
  set, by (1) giving an error, (2) probing for a value or (3) using a
  reasonable default.

  What I can't do is just reject a module out of hand because it may
  take a hardware setting in the module parameters. Some important
  modules, some ipmi stuff for instance, both probe for hardware and
  allow hardware to be manually specified; if the driver is aborts with
  any error, you don't get any ipmi hardware.

  Further, trying to do this entirely in the module initialisation code
  doesn't protect against sysfs twiddling.

  [!] Note that in and of itself, this series of patches should have no
      effect on the the size of the kernel or code execution - that is
      left to a patch in the next series to effect. It does mark
      annotated kernel parameters with a KERNEL_PARAM_FL_HWPARAM flag in
      an already existing field"

* tag 'hwparam-20170420' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs: (38 commits)
  Annotate hardware config module parameters in sound/pci/
  Annotate hardware config module parameters in sound/oss/
  Annotate hardware config module parameters in sound/isa/
  Annotate hardware config module parameters in sound/drivers/
  Annotate hardware config module parameters in fs/pstore/
  Annotate hardware config module parameters in drivers/watchdog/
  Annotate hardware config module parameters in drivers/video/
  Annotate hardware config module parameters in drivers/tty/
  Annotate hardware config module parameters in drivers/staging/vme/
  Annotate hardware config module parameters in drivers/staging/speakup/
  Annotate hardware config module parameters in drivers/staging/media/
  Annotate hardware config module parameters in drivers/scsi/
  Annotate hardware config module parameters in drivers/pcmcia/
  Annotate hardware config module parameters in drivers/pci/hotplug/
  Annotate hardware config module parameters in drivers/parport/
  Annotate hardware config module parameters in drivers/net/wireless/
  Annotate hardware config module parameters in drivers/net/wan/
  Annotate hardware config module parameters in drivers/net/irda/
  Annotate hardware config module parameters in drivers/net/hamradio/
  Annotate hardware config module parameters in drivers/net/ethernet/
  ...
2017-05-10 19:13:03 -07:00
Kees Cook 3a7d2fd16c pstore: Solve lockdep warning by moving inode locks
Lockdep complains about a possible deadlock between mount and unlink
(which is technically impossible), but fixing this improves possible
future multiple-backend support, and keeps locking in the right order.

The lockdep warning could be triggered by unlinking a file in the
pstore filesystem:

  -> #1 (&sb->s_type->i_mutex_key#14){++++++}:
         lock_acquire+0xc9/0x220
         down_write+0x3f/0x70
         pstore_mkfile+0x1f4/0x460
         pstore_get_records+0x17a/0x320
         pstore_fill_super+0xa4/0xc0
         mount_single+0x89/0xb0
         pstore_mount+0x13/0x20
         mount_fs+0xf/0x90
         vfs_kern_mount+0x66/0x170
         do_mount+0x190/0xd50
         SyS_mount+0x90/0xd0
         entry_SYSCALL_64_fastpath+0x1c/0xb1

  -> #0 (&psinfo->read_mutex){+.+.+.}:
         __lock_acquire+0x1ac0/0x1bb0
         lock_acquire+0xc9/0x220
         __mutex_lock+0x6e/0x990
         mutex_lock_nested+0x16/0x20
         pstore_unlink+0x3f/0xa0
         vfs_unlink+0xb5/0x190
         do_unlinkat+0x24c/0x2a0
         SyS_unlinkat+0x16/0x30
         entry_SYSCALL_64_fastpath+0x1c/0xb1

  Possible unsafe locking scenario:

        CPU0                    CPU1
        ----                    ----
   lock(&sb->s_type->i_mutex_key#14);
                                lock(&psinfo->read_mutex);
                                lock(&sb->s_type->i_mutex_key#14);
   lock(&psinfo->read_mutex);

Reported-by: Marta Lofstedt <marta.lofstedt@intel.com>
Reported-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Kees Cook <keescook@chromium.org>
Acked-by: Namhyung Kim <namhyung@kernel.org>
2017-04-27 20:35:34 -07:00
Geliang Tang 3509d048c8 pstore: Remove unused vmalloc.h in pmsg
Since the vmalloc code has been removed from write_pmsg() in the commit
"5bf6d1b pstore/pmsg: drop bounce buffer", remove the unused header
vmalloc.h.

Signed-off-by: Geliang Tang <geliangtang@gmail.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
2017-04-27 14:48:59 -07:00
David Howells b90fe0c4e0 Annotate hardware config module parameters in fs/pstore/
When the kernel is running in secure boot mode, we lock down the kernel to
prevent userspace from modifying the running kernel image.  Whilst this
includes prohibiting access to things like /dev/mem, it must also prevent
access by means of configuring driver modules in such a way as to cause a
device to access or modify the kernel image.

To this end, annotate module_param* statements that refer to hardware
configuration and indicate for future reference what type of parameter they
specify.  The parameter parser in the core sees this information and can
skip such parameters with an error message if the kernel is locked down.
The module initialisation then runs as normal, but just sees whatever the
default values for those parameters is.

Note that we do still need to do the module initialisation because some
drivers have viable defaults set in case parameters aren't specified and
some drivers support automatic configuration (e.g. PNP or PCI) in addition
to manually coded parameters.

This patch annotates drivers in fs/pstore/.

Suggested-by: Alan Cox <gnomes@lxorguk.ukuu.org.uk>
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Kees Cook <keescook@chromium.org>
cc: Anton Vorontsov <anton@enomsg.org>
cc: Colin Cross <ccross@android.com>
cc: Tony Luck <tony.luck@intel.com>
2017-04-20 12:02:32 +01:00
Kees Cook 30800d9977 pstore: simplify write_user_compat()
Nothing actually uses write_user_compat() currently, but there is no
reason to reuse the dmesg buffer. Instead, just allocate a new record
buffer, copy in from userspace, and pass it to write() as normal.

Signed-off-by: Kees Cook <keescook@chromium.org>
2017-03-07 14:01:03 -08:00
Kees Cook 4c9ec21976 pstore: Remove write_buf() callback
Now that write() and write_buf() are functionally identical, this removes
write_buf(), and renames write_buf_user() to write_user(). Additionally
adds sanity-checks for pstore_info's declared functions and flags at
registration time.

Signed-off-by: Kees Cook <keescook@chromium.org>
2017-03-07 14:01:02 -08:00
Kees Cook fdd0311863 pstore: Replace arguments for write_buf_user() API
Removes argument list in favor of pstore record, though the user buffer
remains passed separately since it must carry the __user annotation.

Signed-off-by: Kees Cook <keescook@chromium.org>
2017-03-07 14:01:01 -08:00
Kees Cook b10b471145 pstore: Replace arguments for write_buf() API
As with the other API updates, this removes the long argument list in favor
of passing a single pstore recaord.

Signed-off-by: Kees Cook <keescook@chromium.org>
2017-03-07 14:01:01 -08:00
Kees Cook a61072aae6 pstore: Replace arguments for erase() API
This removes the argument list for the erase() callback and replaces it
with a pointer to the backend record details to be removed.

Signed-off-by: Kees Cook <keescook@chromium.org>
2017-03-07 14:01:00 -08:00
Kees Cook 83f70f0769 pstore: Do not duplicate record metadata
This switches the inode-private data from carrying duplicate metadata to
keeping the record passed in during pstore_mkfile().

Signed-off-by: Kees Cook <keescook@chromium.org>
2017-03-07 14:00:59 -08:00
Kees Cook 2a2b0acf76 pstore: Allocate records on heap instead of stack
In preparation for handling records off to pstore_mkfile(), allocate the
record instead of reusing stack. This still always frees the record,
though, since pstore_mkfile() isn't yet keeping it.

Signed-off-by: Kees Cook <keescook@chromium.org>
2017-03-07 14:00:58 -08:00
Kees Cook 1dfff7dd67 pstore: Pass record contents instead of copying
pstore_mkfile() shouldn't have to memcpy the record contents. It can use
the existing copy instead. This adjusts the allocation lifetime management
and renames the contents variable from "data" to "buf" to assist moving to
struct pstore_record in the future.

Signed-off-by: Kees Cook <keescook@chromium.org>
2017-03-07 14:00:58 -08:00
Kees Cook 7e8cc8dce1 pstore: Always allocate buffer for decompression
Currently, pstore_mkfile() performs a memcpy() of the record contents,
so it can live anywhere. However, this is needlessly wasteful. In
preparation of pstore_mkfile() keeping the record contents, always
allocate a buffer for the contents.

Signed-off-by: Kees Cook <keescook@chromium.org>
2017-03-07 14:00:57 -08:00
Kees Cook 76cc9580e3 pstore: Replace arguments for write() API
Similar to the pstore_info read() callback, there were too many arguments.
This switches to the new struct pstore_record pointer instead. This adds
"reason" and "part" to the record structure as well.

Signed-off-by: Kees Cook <keescook@chromium.org>
2017-03-07 14:00:56 -08:00
Kees Cook 125cc42baf pstore: Replace arguments for read() API
The argument list for the pstore_read() interface is unwieldy. This changes
passes the new struct pstore_record instead. The erst backend was already
doing something similar internally.

Signed-off-by: Kees Cook <keescook@chromium.org>
2017-03-07 14:00:55 -08:00
Kees Cook 1edd1aa397 pstore: Switch pstore_mkfile to pass record
Instead of the long list of arguments, just pass the new record struct.

Signed-off-by: Kees Cook <keescook@chromium.org>
2017-03-07 14:00:55 -08:00
Kees Cook 634f8f5167 pstore: Move record decompression to function
This moves the record decompression logic out to a separate function
to avoid the deep indentation.

Signed-off-by: Kees Cook <keescook@chromium.org>
2017-03-07 14:00:54 -08:00
Kees Cook 9abdcccc3d pstore: Extract common arguments into structure
The read/mkfile pair pass the same arguments and should be cleared
between calls. Move to a structure and wipe it after every loop.

Signed-off-by: Kees Cook <keescook@chromium.org>
2017-03-07 14:00:53 -08:00
Kees Cook 0d7cd09a3d pstore: Improve register_pstore() error reporting
Uncommon errors are better to get reported to dmesg so developers can
more easily figure out why pstore is unhappy with a backend attempting
to register.

Signed-off-by: Kees Cook <keescook@chromium.org>
2017-03-07 08:21:38 -08:00
Kees Cook 1344dd86f3 pstore: Avoid race in module unloading
Technically, it might be possible for struct pstore_info to go out of
scope after the module_put(), so report the backend name first.

Signed-off-by: Kees Cook <keescook@chromium.org>
2017-03-07 08:21:38 -08:00
Kees Cook 6330d55347 pstore: Shut down worker when unregistering
When built as a module and running with update_ms >= 0, pstore will Oops
during module unload since the work timer is still running. This makes sure
the worker is stopped before unloading.

Signed-off-by: Kees Cook <keescook@chromium.org>
Cc: stable@vger.kernel.org
2017-03-07 08:21:38 -08:00
Kees Cook e9a330c428 pstore: Use dynamic spinlock initializer
The per-prz spinlock should be using the dynamic initializer so that
lockdep can correctly track it. Without this, under lockdep, we get a
warning at boot that the lock is in non-static memory.

Fixes: 109704492e ("pstore: Make spinlock per zone instead of global")
Fixes: 76d5692a58 ("pstore: Correctly initialize spinlock and flags")
Signed-off-by: Kees Cook <keescook@chromium.org>
Cc: stable@vger.kernel.org
2017-03-07 08:21:38 -08:00
Bhumika Goyal 3faf93543c pstore: constify pstore_zbackend structures
The references of pstore_zbackend structures are stored into the
pointer zbackend of type struct pstore_zbackend. The pointer zbackend
can be made const as it is only dereferenced. After making this change
the pstore_zbackend structures whose references are stored into the
pointer zbackend can be made const too.

File size before:
   text	   data	    bss	    dec	    hex	filename
   4817	    541	    172	   5530	   159a	fs/pstore/platform.o

File size after:
   text	   data	    bss	    dec	    hex	filename
   4865	    477	    172	   5514	   158a	fs/pstore/platform.o

Signed-off-by: Bhumika Goyal <bhumirks@gmail.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
2017-03-07 08:21:38 -08:00
Sven Schmidt d21b5ff12d fs/pstore: fs/squashfs: change usage of LZ4 to work with new LZ4 version
Update fs/pstore and fs/squashfs to use the updated functions from the
new LZ4 module.

Link: http://lkml.kernel.org/r/1486321748-19085-5-git-send-email-4sschmid@informatik.uni-hamburg.de
Signed-off-by: Sven Schmidt <4sschmid@informatik.uni-hamburg.de>
Cc: Bongkyu Kim <bongkyu.kim@lge.com>
Cc: Rui Salvaterra <rsalvaterra@gmail.com>
Cc: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: David S. Miller <davem@davemloft.net>
Cc: Anton Vorontsov <anton@enomsg.org>
Cc: Colin Cross <ccross@android.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Tony Luck <tony.luck@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-02-24 17:46:57 -08:00
Kees Cook 46418413ed pstore: Check for prz allocation in walker
Instead of needing additional checks in callers for unallocated przs,
perform the check in the walker, which gives us a more universal way to
handle the situation.

Signed-off-by: Kees Cook <keescook@chromium.org>
2017-02-13 10:25:52 -08:00
Kees Cook 76d5692a58 pstore: Correctly initialize spinlock and flags
The ram backend wasn't always initializing its spinlock correctly. Since
it was coming from kzalloc memory, though, it was harmless on
architectures that initialize unlocked spinlocks to 0 (at least x86 and
ARM). This also fixes a possibly ignored flag setting too.

When running under CONFIG_DEBUG_SPINLOCK, the following Oops was visible:

[    0.760836] persistent_ram: found existing buffer, size 29988, start 29988
[    0.765112] persistent_ram: found existing buffer, size 30105, start 30105
[    0.769435] persistent_ram: found existing buffer, size 118542, start 118542
[    0.785960] persistent_ram: found existing buffer, size 0, start 0
[    0.786098] persistent_ram: found existing buffer, size 0, start 0
[    0.786131] pstore: using zlib compression
[    0.790716] BUG: spinlock bad magic on CPU#0, swapper/0/1
[    0.790729]  lock: 0xffffffc0d1ca9bb0, .magic: 00000000, .owner: <none>/-1, .owner_cpu: 0
[    0.790742] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 4.10.0-rc2+ #913
[    0.790747] Hardware name: Google Kevin (DT)
[    0.790750] Call trace:
[    0.790768] [<ffffff900808ae88>] dump_backtrace+0x0/0x2bc
[    0.790780] [<ffffff900808b164>] show_stack+0x20/0x28
[    0.790794] [<ffffff9008460ee0>] dump_stack+0xa4/0xcc
[    0.790809] [<ffffff9008113cfc>] spin_dump+0xe0/0xf0
[    0.790821] [<ffffff9008113d3c>] spin_bug+0x30/0x3c
[    0.790834] [<ffffff9008113e28>] do_raw_spin_lock+0x50/0x1b8
[    0.790846] [<ffffff9008a2d2ec>] _raw_spin_lock_irqsave+0x54/0x6c
[    0.790862] [<ffffff90083ac3b4>] buffer_size_add+0x48/0xcc
[    0.790875] [<ffffff90083acb34>] persistent_ram_write+0x60/0x11c
[    0.790888] [<ffffff90083aab1c>] ramoops_pstore_write_buf+0xd4/0x2a4
[    0.790900] [<ffffff90083a9d3c>] pstore_console_write+0xf0/0x134
[    0.790912] [<ffffff900811c304>] console_unlock+0x48c/0x5e8
[    0.790923] [<ffffff900811da18>] register_console+0x3b0/0x4d4
[    0.790935] [<ffffff90083aa7d0>] pstore_register+0x1a8/0x234
[    0.790947] [<ffffff90083ac250>] ramoops_probe+0x6b8/0x7d4
[    0.790961] [<ffffff90085ca548>] platform_drv_probe+0x7c/0xd0
[    0.790972] [<ffffff90085c76ac>] driver_probe_device+0x1b4/0x3bc
[    0.790982] [<ffffff90085c7ac8>] __device_attach_driver+0xc8/0xf4
[    0.790996] [<ffffff90085c4bfc>] bus_for_each_drv+0xb4/0xe4
[    0.791006] [<ffffff90085c7414>] __device_attach+0xd0/0x158
[    0.791016] [<ffffff90085c7b18>] device_initial_probe+0x24/0x30
[    0.791026] [<ffffff90085c648c>] bus_probe_device+0x50/0xe4
[    0.791038] [<ffffff90085c35b8>] device_add+0x3a4/0x76c
[    0.791051] [<ffffff90087d0e84>] of_device_add+0x74/0x84
[    0.791062] [<ffffff90087d19b8>] of_platform_device_create_pdata+0xc0/0x100
[    0.791073] [<ffffff90087d1a2c>] of_platform_device_create+0x34/0x40
[    0.791086] [<ffffff900903c910>] of_platform_default_populate_init+0x58/0x78
[    0.791097] [<ffffff90080831fc>] do_one_initcall+0x88/0x160
[    0.791109] [<ffffff90090010ac>] kernel_init_freeable+0x264/0x31c
[    0.791123] [<ffffff9008a25bd0>] kernel_init+0x18/0x11c
[    0.791133] [<ffffff9008082ec0>] ret_from_fork+0x10/0x50
[    0.793717] console [pstore-1] enabled
[    0.797845] pstore: Registered ramoops as persistent store backend
[    0.804647] ramoops: attached 0x100000@0xf7edc000, ecc: 0/0

Fixes: 663deb4788 ("pstore: Allow prz to control need for locking")
Fixes: 109704492e ("pstore: Make spinlock per zone instead of global")
Reported-by: Brian Norris <briannorris@chromium.org>
Signed-off-by: Kees Cook <keescook@chromium.org>
2017-02-13 10:25:52 -08:00
Brian Norris 8672aed7bd pstore: don't OOPS when there are no ftrace zones
We'll OOPS in ramoops_get_next_prz() if the platform didn't ask for any
ftrace zones (i.e., cxt->fprzs will be NULL). Let's just skip this
entire FTRACE section if there's no 'fprzs'.

Regression seen on a coreboot/depthcharge-based Chromebook.

Fixes: 2fbea82bbb ("pstore: Merge per-CPU ftrace records into one")
Cc: Joel Fernandes <joelaf@google.com>
Cc: Kees Cook <keescook@chromium.org>
Signed-off-by: Brian Norris <briannorris@chromium.org>
Signed-off-by: Kees Cook <keescook@chromium.org>
2017-02-09 11:49:49 -08:00
Linus Torvalds 52281b38bc Improvements and fixes to pstore subsystem:
- Add additional checks for bad platform data
 
 - Remove bounce buffer in console writer
 
 - Protect read/unlink race with a mutex
 
 - Correctly give up during dump locking failures
 
 - Increase ftrace bandwidth by splitting ftrace buffers per CPU
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Merge tag 'pstore-v4.10-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux

Pull pstore updates from Kees Cook:
 "Improvements and fixes to pstore subsystem:

   - add additional checks for bad platform data

   - remove bounce buffer in console writer

   - protect read/unlink race with a mutex

   - correctly give up during dump locking failures

   - increase ftrace bandwidth by splitting ftrace buffers per CPU"

* tag 'pstore-v4.10-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux:
  ramoops: add pdata NULL check to ramoops_probe
  pstore: Convert console write to use ->write_buf
  pstore: Protect unlink with read_mutex
  pstore: Use global ftrace filters for function trace filtering
  ftrace: Provide API to use global filtering for ftrace ops
  pstore: Clarify context field przs as dprzs
  pstore: improve error report for failed setup
  pstore: Merge per-CPU ftrace records into one
  pstore: Add ftrace timestamp counter
  ramoops: Split ftrace buffer space into per-CPU zones
  pstore: Make ramoops_init_przs generic for other prz arrays
  pstore: Allow prz to control need for locking
  pstore: Warn on PSTORE_TYPE_PMSG using deprecated function
  pstore: Make spinlock per zone instead of global
  pstore: Actually give up during locking failure
2016-12-13 09:16:11 -08:00
Kees Cook fc46d4e453 ramoops: add pdata NULL check to ramoops_probe
This adds a check for a NULL platform data, which should only be possible
if a driver incorrectly sets up a probe request without also having defined
the platform_data structure. This is based on a patch from Geliang Tang.

Signed-off-by: Kees Cook <keescook@chromium.org>
2016-11-15 16:34:32 -08:00
Namhyung Kim 70ad35db33 pstore: Convert console write to use ->write_buf
Maybe I'm missing something, but I don't know why it needs to copy the
input buffer to psinfo->buf and then write.  Instead we can write the
input buffer directly.  The only implementation that supports console
message (i.e. ramoops) already does it for ftrace messages.

For the upcoming virtio backend driver, it needs to protect psinfo->buf
overwritten from console messages.  If it could use ->write_buf method
instead of ->write, the problem will be solved easily.

Cc: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Kees Cook <keescook@chromium.org>
2016-11-15 16:34:32 -08:00
Namhyung Kim e9e360b08a pstore: Protect unlink with read_mutex
When update_ms is set, pstore_get_records() will be called when there's
a new entry.  But unlink can be called at the same time and might
contend with the open-read-close loop.  Depending on the implementation
of platform driver, it may be safe or not.  But I think it'd be better
to protect those race in the first place.

Cc: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Kees Cook <keescook@chromium.org>
2016-11-15 16:34:31 -08:00
Joel Fernandes 7a0032f504 pstore: Use global ftrace filters for function trace filtering
Currently, pstore doesn't have any filters setup for function tracing.
This has the associated overhead and may not be useful for users looking
for tracing specific set of functions.

ftrace's regular function trace filtering is done writing to
tracing/set_ftrace_filter however this is not available if not requested.
In order to be able to use this feature, the support to request global
filtering introduced earlier in the series should be requested before
registering the ftrace ops. Here we do the same.

Signed-off-by: Joel Fernandes <joelaf@google.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
2016-11-15 16:34:30 -08:00
Kees Cook a5d23b956c pstore: Clarify context field przs as dprzs
Since "przs" (persistent ram zones) is a general name in the code now, so
rename the Oops-dump zones to dprzs from przs.

Based on a patch from Nobuhiro Iwamatsu.

Signed-off-by: Kees Cook <keescook@chromium.org>
2016-11-15 16:34:29 -08:00
Kees Cook c443a5f3f1 pstore: improve error report for failed setup
When setting ramoops record sizes, sometimes it's not clear which
parameters contributed to the allocation failure. This adds a per-zone
name and expands the failure reports.

Signed-off-by: Kees Cook <keescook@chromium.org>
2016-11-15 16:34:28 -08:00
Joel Fernandes 2fbea82bbb pstore: Merge per-CPU ftrace records into one
Up until this patch, each of the per CPU ftrace buffers appear as a
separate ftrace-ramoops-N file. In this patch we merge all the zones into
one and populate a single ftrace-ramoops-0 file.

Signed-off-by: Joel Fernandes <joelaf@google.com>
[kees: clarified variables names, added -ENOMEM handling]
Signed-off-by: Kees Cook <keescook@chromium.org>
2016-11-15 16:34:28 -08:00
Joel Fernandes fbccdeb8d7 pstore: Add ftrace timestamp counter
In preparation for merging the per CPU buffers into one buffer when
we retrieve the pstore ftrace data, we store the timestamp as a
counter in the ftrace pstore record.  We store the CPU number as well
if !PSTORE_CPU_IN_IP, in this case we shift the counter and may lose
ordering there but we preserve the same record size. The timestamp counter
is also racy, and not doing any locking or synchronization here results
in the benefit of lower overhead. Since we don't care much here for exact
ordering of function traces across CPUs, we don't synchronize and may lose
some counter updates but I'm ok with that.

Using trace_clock() results in much lower performance so avoid using it
since we don't want accuracy in timestamp and need a rough ordering to
perform merge.

Signed-off-by: Joel Fernandes <joelaf@google.com>
[kees: updated commit message, added comments]
Signed-off-by: Kees Cook <keescook@chromium.org>
2016-11-15 16:34:27 -08:00
Joel Fernandes a1cf53ac6d ramoops: Split ftrace buffer space into per-CPU zones
If the RAMOOPS_FLAG_FTRACE_PER_CPU flag is passed to ramoops pdata, split
the ftrace space into multiple zones depending on the number of CPUs.

This speeds up the performance of function tracing by about 280% in my
tests as we avoid the locking. The trade off being lesser space available
per CPU. Let the ramoops user decide which option they want based on pdata
flag.

Signed-off-by: Joel Fernandes <joelaf@google.com>
[kees: added max_ftrace_cnt to track size, added DT logic and docs]
Signed-off-by: Kees Cook <keescook@chromium.org>
2016-11-15 16:34:26 -08:00
Kees Cook de83209249 pstore: Make ramoops_init_przs generic for other prz arrays
Currently ramoops_init_przs() is hard wired only for panic dump zone
array. In preparation for the ftrace zone array (one zone per-cpu) and pmsg
zone array, make the function more generic to be able to handle this case.

Heavily based on similar work from Joel Fernandes.

Signed-off-by: Kees Cook <keescook@chromium.org>
2016-11-15 16:34:25 -08:00
Joel Fernandes 663deb4788 pstore: Allow prz to control need for locking
In preparation of not locking at all for certain buffers depending on if
there's contention, make locking optional depending on the initialization
of the prz.

Signed-off-by: Joel Fernandes <joelaf@google.com>
[kees: moved locking flag into prz instead of via caller arguments]
Signed-off-by: Kees Cook <keescook@chromium.org>
2016-11-15 16:34:25 -08:00
Joel Fernandes d8991f51e5 pstore: Warn on PSTORE_TYPE_PMSG using deprecated function
PMSG now uses ramoops_pstore_write_buf_user() instead of ...write_buf().
Print a ratelimited warning if gets accidentally called.

Signed-off-by: Joel Fernandes <joelaf@google.com>
[kees: adjusted commit log and added -EINVAL return]
Signed-off-by: Kees Cook <keescook@chromium.org>
2016-11-11 10:36:46 -08:00
Joel Fernandes 109704492e pstore: Make spinlock per zone instead of global
Currently pstore has a global spinlock for all zones. Since the zones
are independent and modify different areas of memory, there's no need
to have a global lock, so we should use a per-zone lock as introduced
here. Also, when ramoops's ftrace use-case has a FTRACE_PER_CPU flag
introduced later, which splits the ftrace memory area into a single zone
per CPU, it will eliminate the need for locking. In preparation for this,
make the locking optional.

Signed-off-by: Joel Fernandes <joelaf@google.com>
[kees: updated commit message]
Signed-off-by: Kees Cook <keescook@chromium.org>
2016-11-11 10:35:37 -08:00
Li Pengcheng 959217c84c pstore: Actually give up during locking failure
Without a return after the pr_err(), dumps will collide when two threads
call pstore_dump() at the same time.

Signed-off-by: Liu Hailong <liuhailong5@huawei.com>
Signed-off-by: Li Pengcheng <lipengcheng8@huawei.com>
Signed-off-by: Li Zhong <lizhong11@hisilicon.com>
[kees: improved commit message]
Signed-off-by: Kees Cook <keescook@chromium.org>
2016-11-08 16:44:33 -08:00
Mauro Carvalho Chehab 8c27ceff36 docs: fix locations of several documents that got moved
The previous patch renamed several files that are cross-referenced
along the Kernel documentation. Adjust the links to point to
the right places.

Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
2016-10-24 08:12:35 -02:00
Linus Torvalds 101105b171 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull more vfs updates from Al Viro:
 ">rename2() work from Miklos + current_time() from Deepa"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  fs: Replace current_fs_time() with current_time()
  fs: Replace CURRENT_TIME_SEC with current_time() for inode timestamps
  fs: Replace CURRENT_TIME with current_time() for inode timestamps
  fs: proc: Delete inode time initializations in proc_alloc_inode()
  vfs: Add current_time() api
  vfs: add note about i_op->rename changes to porting
  fs: rename "rename2" i_op to "rename"
  vfs: remove unused i_op->rename
  fs: make remaining filesystems use .rename2
  libfs: support RENAME_NOREPLACE in simple_rename()
  fs: support RENAME_NOREPLACE for local filesystems
  ncpfs: fix unused variable warning
2016-10-10 20:16:43 -07:00
Deepa Dinamani 078cd8279e fs: Replace CURRENT_TIME with current_time() for inode timestamps
CURRENT_TIME macro is not appropriate for filesystems as it
doesn't use the right granularity for filesystem timestamps.
Use current_time() instead.

CURRENT_TIME is also not y2038 safe.

This is also in preparation for the patch that transitions
vfs timestamps to use 64 bit time and hence make them
y2038 safe. As part of the effort current_time() will be
extended to do range checks. Hence, it is necessary for all
file system timestamps to use current_time(). Also,
current_time() will be transitioned along with vfs to be
y2038 safe.

Note that whenever a single call to current_time() is used
to change timestamps in different inodes, it is because they
share the same time granularity.

Signed-off-by: Deepa Dinamani <deepa.kernel@gmail.com>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Felipe Balbi <balbi@kernel.org>
Acked-by: Steven Whitehouse <swhiteho@redhat.com>
Acked-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Acked-by: David Sterba <dsterba@suse.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-09-27 21:06:21 -04:00
Geliang Tang f88baf68eb ramoops: move spin_lock_init after kmalloc error checking
If cxt->pstore.buf allocated failed, no need to initialize
cxt->pstore.buf_lock. So this patch moves spin_lock_init() after the
error checking.

Signed-off-by: Geliang Tang <geliangtang@gmail.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
2016-09-08 15:01:13 -07:00
Andrew Bresticker d771fdf941 pstore/ram: Use memcpy_fromio() to save old buffer
The ramoops buffer may be mapped as either I/O memory or uncached
memory.  On ARM64, this results in a device-type (strongly-ordered)
mapping.  Since unnaligned accesses to device-type memory will
generate an alignment fault (regardless of whether or not strict
alignment checking is enabled), it is not safe to use memcpy().
memcpy_fromio() is guaranteed to only use aligned accesses, so use
that instead.

Signed-off-by: Andrew Bresticker <abrestic@chromium.org>
Signed-off-by: Enric Balletbo Serra <enric.balletbo@collabora.com>
Reviewed-by: Puneet Kumar <puneetster@chromium.org>
Signed-off-by: Kees Cook <keescook@chromium.org>
Cc: stable@vger.kernel.org
2016-09-08 15:01:12 -07:00
Furquan Shaikh 7e75678d23 pstore/ram: Use memcpy_toio instead of memcpy
persistent_ram_update uses vmap / iomap based on whether the buffer is in
memory region or reserved region. However, both map it as non-cacheable
memory. For armv8 specifically, non-cacheable mapping requests use a
memory type that has to be accessed aligned to the request size. memcpy()
doesn't guarantee that.

Signed-off-by: Furquan Shaikh <furquan@google.com>
Signed-off-by: Enric Balletbo Serra <enric.balletbo@collabora.com>
Reviewed-by: Aaron Durbin <adurbin@chromium.org>
Reviewed-by: Olof Johansson <olofj@chromium.org>
Tested-by: Furquan Shaikh <furquan@chromium.org>
Signed-off-by: Kees Cook <keescook@chromium.org>
Cc: stable@vger.kernel.org
2016-09-08 15:01:11 -07:00
Mark Salyzyn 5bf6d1b927 pstore/pmsg: drop bounce buffer
Removing a bounce buffer copy operation in the pmsg driver path is
always better. We also gain in overall performance by not requesting
a vmalloc on every write as this can cause precious RT tasks, such
as user facing media operation, to stall while memory is being
reclaimed. Added a write_buf_user to the pstore functions, a backup
platform write_buf_user that uses the small buffer that is part of
the instance, and implemented a ramoops write_buf_user that only
supports PSTORE_TYPE_PMSG.

Signed-off-by: Mark Salyzyn <salyzyn@android.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
2016-09-08 15:01:10 -07:00
Namhyung Kim 79d955af71 pstore/ram: Set pstore flags dynamically
The ramoops can be configured to enable each pstore type by setting
their size.  In that case, it'd be better not to register disabled types
in the first place.

Cc: Anton Vorontsov <anton@enomsg.org>
Cc: Colin Cross <ccross@android.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Tony Luck <tony.luck@intel.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Kees Cook <keescook@chromium.org>
2016-09-08 15:01:09 -07:00
Namhyung Kim c950fd6f20 pstore: Split pstore fragile flags
This patch adds new PSTORE_FLAGS for each pstore type so that they can
be enabled separately.  This is a preparation for ongoing virtio-pstore
work to support those types flexibly.

The PSTORE_FLAGS_FRAGILE is changed to PSTORE_FLAGS_DMESG to preserve the
original behavior.

Cc: Anton Vorontsov <anton@enomsg.org>
Cc: Colin Cross <ccross@android.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Tony Luck <tony.luck@intel.com>
Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>
Cc: Len Brown <lenb@kernel.org>
Cc: Matt Fleming <matt@codeblueprint.co.uk>
Cc: linux-acpi@vger.kernel.org
Cc: linux-efi@vger.kernel.org
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
[kees: retained "FRAGILE" for now to make merges easier]
Signed-off-by: Kees Cook <keescook@chromium.org>
2016-09-08 15:01:08 -07:00
Sebastian Andrzej Siewior d5a9bf0b38 pstore/core: drop cmpxchg based updates
I have here a FPGA behind PCIe which exports SRAM which I use for
pstore. Now it seems that the FPGA no longer supports cmpxchg based
updates and writes back 0xff…ff and returns the same.  This leads to
crash during crash rendering pstore useless.
Since I doubt that there is much benefit from using cmpxchg() here, I am
dropping this atomic access and use the spinlock based version.

Cc: Anton Vorontsov <anton@enomsg.org>
Cc: Colin Cross <ccross@android.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Rabin Vincent <rabinv@axis.com>
Tested-by: Rabin Vincent <rabinv@axis.com>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
[kees: remove "_locked" suffix since it's the only option now]
Signed-off-by: Kees Cook <keescook@chromium.org>
Cc: stable@vger.kernel.org
2016-09-08 15:00:47 -07:00
Sebastian Andrzej Siewior 4407de74df pstore/ramoops: fixup driver removal
A basic rmmod ramoops segfaults. Let's see why.

Since commit 34f0ec82e0 ("pstore: Correct the max_dump_cnt clearing of
ramoops") sets ->max_dump_cnt to zero before looping over ->przs but we
didn't use it before that either.

And since commit ee1d267423 ("pstore: add pstore unregister") we free
that memory on rmmod.

But even then, we looped until a NULL pointer or ERR. I don't see where
it is ensured that the last member is NULL. Let's try this instead:
simply error recovery and free. Clean up in error case where resources
were allocated. And then, in the free path, rely on ->max_dump_cnt in
the free path.

Cc: Anton Vorontsov <anton@enomsg.org>
Cc: Colin Cross <ccross@android.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Kees Cook <keescook@chromium.org>
Cc: stable@vger.kernel.org # 4.4.x-
2016-09-08 14:58:00 -07:00
Hiraku Toyooka e976e56423 ramoops: use persistent_ram_free() instead of kfree() for freeing prz
persistent_ram_zone(=prz) structures are allocated by persistent_ram_new(),
which includes vmap() or ioremap(). But they are currently freed by
kfree(). This uses persistent_ram_free() for correct this asymmetry usage.

Signed-off-by: Hiraku Toyooka <hiraku.toyooka.gu@hitachi.com>
Signed-off-by: Nobuhiro Iwamatsu <nobuhiro.iwamatsu.kw@hitachi.com>
Cc: Mark Salyzyn <salyzyn@android.com>
Cc: Seiji Aguchi <seiji.aguchi.tr@hitachi.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
2016-08-05 11:21:46 -07:00
Kees Cook 529182e204 ramoops: use DT reserved-memory bindings
Instead of a ramoops-specific node, use a child node of /reserved-memory.
This requires that of_platform_device_create() be explicitly called
for the node, though, since "/reserved-memory" does not have its own
"compatible" property.

Suggested-by: Rob Herring <robh@kernel.org>
Signed-off-by: Kees Cook <keescook@chromium.org>
Acked-by: Rob Herring <robh@kernel.org>
2016-08-05 11:21:36 -07:00
Greg Hackmann 35da60941e pstore/ram: add Device Tree bindings
ramoops is one of the remaining places where ARM vendors still rely on
board-specific shims.  Device Tree lets us replace those shims with
generic code.

These bindings mirror the ramoops module parameters, with two small
differences:

(1) dump_oops becomes an optional "no-dump-oops" property, since ramoops
    sets dump_oops=1 by default.

(2) mem_type=1 becomes the more self-explanatory "unbuffered" property.

Signed-off-by: Greg Hackmann <ghackmann@google.com>
[fixed platform_get_drvdata() crash, thanks to Brian Norris]
[switched from u64 to u32 to simplify code, various whitespace fixes]
[use dev_of_node() to gain code-elimination for CONFIG_OF=n]
Signed-off-by: Kees Cook <keescook@chromium.org>
2016-06-14 11:34:39 -07:00
Geliang Tang 52d210d961 pstore: drop file opened reference count
In ee1d267423 ("pstore: add pstore unregister") I added:
	.owner = THIS_MODULE,
in both pstore_fs_type and pstore_file_operations to increase a reference
count when pstore filesystem is mounted and pstore file is opened.

But, it's repetitive. There is no need to increase the opened reference
count. We only need to increase the mounted reference count. When a file
is opened, the filesystem can't be unmounted. Hence the pstore module
can't be unloaded either.

So I drop the opened reference count in this patch.

Fixes: ee1d267423 ("pstore: add pstore unregister")
Signed-off-by: Geliang Tang <geliangtang@163.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
2016-06-02 11:24:52 -07:00
Geliang Tang 8cfc8ddc99 pstore: add lzo/lz4 compression support
Like zlib compression in pstore, this patch added lzo and lz4
compression support so that users can have more options and better
compression ratio.

The original code treats the compressed data together with the
uncompressed ECC correction notice by using zlib decompress. The
ECC correction notice is missing in the decompression process. The
treatment also makes lzo and lz4 not working. So I treat them
separately by using pstore_decompress() to treat the compressed
data, and memcpy() to treat the uncompressed ECC correction notice.

Signed-off-by: Geliang Tang <geliangtang@163.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
2016-06-02 10:59:31 -07:00
Namhyung Kim 235f6d157d pstore: Cleanup pstore_dump()
The code is duplicate between compression is enabled or not.

Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Kees Cook <keescook@chromium.org>
2016-05-31 12:36:45 -07:00
Namhyung Kim 98e44fda2e pstore: Enable compression on normal path (again)
The commit f0e2efcfd2 ("pstore: do not use message compression
without lock") added a check to 'is_locked' to avoid breakage in
concurrent accesses.  But it has a side-effect of disabling compression
on normal path since 'is_locked' variable is not set.  As normal path
always takes the lock, it should be initialized to 1.

This also makes the unlock code a bit simpler.

Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Kees Cook <keescook@chromium.org>
2016-05-31 12:36:44 -07:00
Kees Cook a1db8060f5 ramoops: Only unregister when registered
While none of the "fragile" pstore backends unregister yet, if they
ever did, the unregistering code for the non-dump targets might get
confused. This adds a check for fragile backends on unregister.

Signed-off-by: Kees Cook <keescook@chromium.org>
2016-05-31 12:36:44 -07:00
Kirill A. Shutemov 09cbfeaf1a mm, fs: get rid of PAGE_CACHE_* and page_cache_{get,release} macros
PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} macros were introduced *long* time
ago with promise that one day it will be possible to implement page
cache with bigger chunks than PAGE_SIZE.

This promise never materialized.  And unlikely will.

We have many places where PAGE_CACHE_SIZE assumed to be equal to
PAGE_SIZE.  And it's constant source of confusion on whether
PAGE_CACHE_* or PAGE_* constant should be used in a particular case,
especially on the border between fs and mm.

Global switching to PAGE_CACHE_SIZE != PAGE_SIZE would cause to much
breakage to be doable.

Let's stop pretending that pages in page cache are special.  They are
not.

The changes are pretty straight-forward:

 - <foo> << (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> <foo>;

 - <foo> >> (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> <foo>;

 - PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} -> PAGE_{SIZE,SHIFT,MASK,ALIGN};

 - page_cache_get() -> get_page();

 - page_cache_release() -> put_page();

This patch contains automated changes generated with coccinelle using
script below.  For some reason, coccinelle doesn't patch header files.
I've called spatch for them manually.

The only adjustment after coccinelle is revert of changes to
PAGE_CAHCE_ALIGN definition: we are going to drop it later.

There are few places in the code where coccinelle didn't reach.  I'll
fix them manually in a separate patch.  Comments and documentation also
will be addressed with the separate patch.

virtual patch

@@
expression E;
@@
- E << (PAGE_CACHE_SHIFT - PAGE_SHIFT)
+ E

@@
expression E;
@@
- E >> (PAGE_CACHE_SHIFT - PAGE_SHIFT)
+ E

@@
@@
- PAGE_CACHE_SHIFT
+ PAGE_SHIFT

@@
@@
- PAGE_CACHE_SIZE
+ PAGE_SIZE

@@
@@
- PAGE_CACHE_MASK
+ PAGE_MASK

@@
expression E;
@@
- PAGE_CACHE_ALIGN(E)
+ PAGE_ALIGN(E)

@@
expression E;
@@
- page_cache_get(E)
+ get_page(E)

@@
expression E;
@@
- page_cache_release(E)
+ put_page(E)

Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-04-04 10:41:08 -07:00
Wiebe, Wladislav (Nokia - DE/Ulm) 764fd639d7 pstore: Add support for 64 Bit address space
Some architectures have their reserved RAM in 64 Bit address space.
Therefore convert mem_address module parameter to ullong.

Signed-off-by: Wladislav Wiebe <wladislav.wiebe@nokia.com>
Acked-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Tony Luck <tony.luck@intel.com>
2016-03-10 09:43:36 -08:00
Al Viro 5955102c99 wrappers for ->i_mutex access
parallel to mutex_{lock,unlock,trylock,is_locked,lock_nested},
inode_foo(inode) being mutex_foo(&inode->i_mutex).

Please, use those for access to ->i_mutex; over the coming cycle
->i_mutex will become rwsem, with ->lookup() done with it held
only shared.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-01-22 18:04:28 -05:00
Geliang Tang 306e5c2a3c pstore: fix code comment to match code
Fix code comment about kmsg_dump register so it matches the code.

Signed-off-by: Geliang Tang <geliangtang@163.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
2015-11-02 13:41:52 -08:00
Geliang Tang 7e26e9ff0a pstore: Fix return type of pstore_is_mounted()
This patch changes return type of pstore_is_mounted from int to bool.

Signed-off-by: Geliang Tang <geliangtang@163.com>
Acked-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Tony Luck <tony.luck@intel.com>
2015-10-22 10:57:33 -07:00
Geliang Tang ee1d267423 pstore: add pstore unregister
pstore doesn't support unregistering yet. It was marked as TODO.
This patch adds some code to fix it:
 1) Add functions to unregister kmsg/console/ftrace/pmsg.
 2) Add a function to free compression buffer.
 3) Unmap the memory and free it.
 4) Add a function to unregister pstore filesystem.

Signed-off-by: Geliang Tang <geliangtang@163.com>
Acked-by: Kees Cook <keescook@chromium.org>
[Removed __exit annotation from ramoops_remove(). Reported by Arnd Bergmann]
Signed-off-by: Tony Luck <tony.luck@intel.com>
2015-10-22 08:59:18 -07:00
Geliang Tang 1873041152 pstore: add a helper function pstore_register_kmsg
Add a new wrapper function pstore_register_kmsg to keep the
consistency with other similar pstore_register_* functions.

Signed-off-by: Geliang Tang <geliangtang@163.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
2015-10-21 09:27:10 -07:00
Geliang Tang 549b39a9e7 pstore: add vmalloc error check
If vmalloc fails, make write_pmsg return -ENOMEM.

Signed-off-by: Geliang Tang <geliangtang@163.com>
Acked-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Tony Luck <tony.luck@intel.com>
2015-10-21 09:27:10 -07:00
Linus Torvalds 0cbee99269 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace
Pull user namespace updates from Eric Biederman:
 "Long ago and far away when user namespaces where young it was realized
  that allowing fresh mounts of proc and sysfs with only user namespace
  permissions could violate the basic rule that only root gets to decide
  if proc or sysfs should be mounted at all.

  Some hacks were put in place to reduce the worst of the damage could
  be done, and the common sense rule was adopted that fresh mounts of
  proc and sysfs should allow no more than bind mounts of proc and
  sysfs.  Unfortunately that rule has not been fully enforced.

  There are two kinds of gaps in that enforcement.  Only filesystems
  mounted on empty directories of proc and sysfs should be ignored but
  the test for empty directories was insufficient.  So in my tree
  directories on proc, sysctl and sysfs that will always be empty are
  created specially.  Every other technique is imperfect as an ordinary
  directory can have entries added even after a readdir returns and
  shows that the directory is empty.  Special creation of directories
  for mount points makes the code in the kernel a smidge clearer about
  it's purpose.  I asked container developers from the various container
  projects to help test this and no holes were found in the set of mount
  points on proc and sysfs that are created specially.

  This set of changes also starts enforcing the mount flags of fresh
  mounts of proc and sysfs are consistent with the existing mount of
  proc and sysfs.  I expected this to be the boring part of the work but
  unfortunately unprivileged userspace winds up mounting fresh copies of
  proc and sysfs with noexec and nosuid clear when root set those flags
  on the previous mount of proc and sysfs.  So for now only the atime,
  read-only and nodev attributes which userspace happens to keep
  consistent are enforced.  Dealing with the noexec and nosuid
  attributes remains for another time.

  This set of changes also addresses an issue with how open file
  descriptors from /proc/<pid>/ns/* are displayed.  Recently readlink of
  /proc/<pid>/fd has been triggering a WARN_ON that has not been
  meaningful since it was added (as all of the code in the kernel was
  converted) and is not now actively wrong.

  There is also a short list of issues that have not been fixed yet that
  I will mention briefly.

  It is possible to rename a directory from below to above a bind mount.
  At which point any directory pointers below the renamed directory can
  be walked up to the root directory of the filesystem.  With user
  namespaces enabled a bind mount of the bind mount can be created
  allowing the user to pick a directory whose children they can rename
  to outside of the bind mount.  This is challenging to fix and doubly
  so because all obvious solutions must touch code that is in the
  performance part of pathname resolution.

  As mentioned above there is also a question of how to ensure that
  developers by accident or with purpose do not introduce exectuable
  files on sysfs and proc and in doing so introduce security regressions
  in the current userspace that will not be immediately obvious and as
  such are likely to require breaking userspace in painful ways once
  they are recognized"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace:
  vfs: Remove incorrect debugging WARN in prepend_path
  mnt: Update fs_fully_visible to test for permanently empty directories
  sysfs: Create mountpoints with sysfs_create_mount_point
  sysfs: Add support for permanently empty directories to serve as mount points.
  kernfs: Add support for always empty directories.
  proc: Allow creating permanently empty directories that serve as mount points
  sysctl: Allow creating permanently empty directories that serve as mountpoints.
  fs: Add helper functions for permanently empty directories.
  vfs: Ignore unlocked mounts in fs_fully_visible
  mnt: Modify fs_fully_visible to deal with locked ro nodev and atime
  mnt: Refactor the logic for mounting sysfs and proc in a user namespace
2015-07-03 15:20:57 -07:00
Eric W. Biederman f9bb48825a sysfs: Create mountpoints with sysfs_create_mount_point
This allows for better documentation in the code and
it allows for a simpler and fully correct version of
fs_fully_visible to be written.

The mount points converted and their filesystems are:
/sys/hypervisor/s390/       s390_hypfs
/sys/kernel/config/         configfs
/sys/kernel/debug/          debugfs
/sys/firmware/efi/efivars/  efivarfs
/sys/fs/fuse/connections/   fusectl
/sys/fs/pstore/             pstore
/sys/kernel/tracing/        tracefs
/sys/fs/cgroup/             cgroup
/sys/kernel/security/       securityfs
/sys/fs/selinux/            selinuxfs
/sys/fs/smackfs/            smackfs

Cc: stable@vger.kernel.org
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2015-07-01 10:36:47 -05:00
Wang Long 078550569e ramoops: make it possible to change mem_type param.
If we set ramoops.mem_type=1 in command line, the current
code can not change mem_type to 1, because it is assigned
to 0 in function ramoops_register_dummy.

This patch make it possible to change mem_type parameter
in command line.

Signed-off-by: Wang Long <long.wanglong@huawei.com>
Acked-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
2015-05-21 09:52:29 -07:00
Ben Zhang e036bd330d pstore/ram: verify ramoops header before saving record
On some devices the persistent memory contains junk after a cold boot,
and /dev/pstore/dmesg-ramoops-* are created with random data which is
not the result of a kernel crash.

This patch adds a ramoops header check and skips any
persistent_ram_zone that does not have a valid header.

Signed-off-by: Ben Zhang <benzh@chromium.org>
Signed-off-by: Tony Luck <tony.luck@intel.com>
2015-05-21 09:50:34 -07:00
long.wanglong 07239fc854 fs/pstore: Optimization function ramoops_init_przs
The value of cxt->record_size does not change in the loop,
so this patch optimize the assign statement by dropping
sz entirely and using cxt->record_size in its place.

Signed-off-by: Wang Long <long.wanglong@huawei.com>
Acked-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Tony Luck <tony.luck@intel.com>
2015-05-21 09:47:22 -07:00
Wang Long 42222c2a5d fs/pstore: update the backend parameter in pstore module
This patch update the module parameter backend, so it is visible
through /sys/module/pstore/parameters/backend.

For example:
if pstore backend is ramoops, with this patch:
	# cat /sys/module/pstore/parameters/backend
	ramoops
and without this patch:
	# cat /sys/module/pstore/parameters/backend
	(null)

Signed-off-by: Wang Long <long.wanglong@huawei.com>
Acked-by: Mark Salyzyn <salyzyn@android.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
2015-05-21 09:34:22 -07:00
Konstantin Khlebnikov f0e2efcfd2 pstore: do not use message compression without lock
pstore_compress() uses static stream buffer for zlib-deflate which
easily crashes when several concurrent threads use one shared state.

Signed-off-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Signed-off-by: Tony Luck <tony.luck@intel.com>
2015-05-21 09:26:19 -07:00
Linus Torvalds 9ec3a646fe Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull fourth vfs update from Al Viro:
 "d_inode() annotations from David Howells (sat in for-next since before
  the beginning of merge window) + four assorted fixes"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  RCU pathwalk breakage when running into a symlink overmounting something
  fix I_DIO_WAKEUP definition
  direct-io: only inc/dec inode->i_dio_count for file systems
  fs/9p: fix readdir()
  VFS: assorted d_backing_inode() annotations
  VFS: fs/inode.c helpers: d_inode() annotations
  VFS: fs/cachefiles: d_backing_inode() annotations
  VFS: fs library helpers: d_inode() annotations
  VFS: assorted weird filesystems: d_inode() annotations
  VFS: normal filesystems (and lustre): d_inode() annotations
  VFS: security/: d_inode() annotations
  VFS: security/: d_backing_inode() annotations
  VFS: net/: d_inode() annotations
  VFS: net/unix: d_backing_inode() annotations
  VFS: kernel/: d_inode() annotations
  VFS: audit: d_backing_inode() annotations
  VFS: Fix up some ->d_inode accesses in the chelsio driver
  VFS: Cachefiles should perform fs modifications on the top layer only
  VFS: AF_UNIX sockets should call mknod on the top layer only
2015-04-26 17:22:07 -07:00
Linus Torvalds d19d5efd8c powerpc updates for 4.1
- Numerous minor fixes, cleanups etc.
 - More EEH work from Gavin to remove its dependency on device_nodes.
 - Memory hotplug implemented entirely in the kernel from Nathan Fontenot.
 - Removal of redundant CONFIG_PPC_OF by Kevin Hao.
 - Rewrite of VPHN parsing logic & tests from Greg Kurz.
 - A fix from Nish Aravamudan to reduce memory usage by clamping
   nodes_possible_map.
 - Support for pstore on powernv from Hari Bathini.
 - Removal of old powerpc specific byte swap routines by David Gibson.
 - Fix from Vasant Hegde to prevent the flash driver telling you it was flashing
   your firmware when it wasn't.
 - Patch from Ben Herrenschmidt to add an OPAL heartbeat driver.
 - Fix for an oops causing get/put_cpu_var() imbalance in perf by Jan Stancek.
 - Some fixes for migration from Tyrel Datwyler.
 - A new syscall to switch the cpu endian by Michael Ellerman.
 - Large series from Wei Yang to implement SRIOV, reviewed and acked by Bjorn.
 - A fix for the OPAL sensor driver from Cédric Le Goater.
 - Fixes to get STRICT_MM_TYPECHECKS building again by Michael Ellerman.
 - Large series from Daniel Axtens to make our PCI hooks per PHB rather than per
   machine.
 - Small patch from Sam Bobroff to explicitly abort non-suspended transactions
   on syscalls, plus a test to exercise it.
 - Numerous reworks and fixes for the 24x7 PMU from Sukadev Bhattiprolu.
 - Small patch to enable the hard lockup detector from Anton Blanchard.
 - Fix from Dave Olson for missing L2 cache information on some CPUs.
 - Some fixes from Michael Ellerman to get Cell machines booting again.
 - Freescale updates from Scott: Highlights include BMan device tree nodes, an
   MSI erratum workaround, a couple minor performance improvements, config
   updates, and misc fixes/cleanup.
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Merge tag 'powerpc-4.1-1' of git://git.kernel.org/pub/scm/linux/kernel/git/mpe/linux

Pull powerpc updates from Michael Ellerman:

 - Numerous minor fixes, cleanups etc.

 - More EEH work from Gavin to remove its dependency on device_nodes.

 - Memory hotplug implemented entirely in the kernel from Nathan
   Fontenot.

 - Removal of redundant CONFIG_PPC_OF by Kevin Hao.

 - Rewrite of VPHN parsing logic & tests from Greg Kurz.

 - A fix from Nish Aravamudan to reduce memory usage by clamping
   nodes_possible_map.

 - Support for pstore on powernv from Hari Bathini.

 - Removal of old powerpc specific byte swap routines by David Gibson.

 - Fix from Vasant Hegde to prevent the flash driver telling you it was
   flashing your firmware when it wasn't.

 - Patch from Ben Herrenschmidt to add an OPAL heartbeat driver.

 - Fix for an oops causing get/put_cpu_var() imbalance in perf by Jan
   Stancek.

 - Some fixes for migration from Tyrel Datwyler.

 - A new syscall to switch the cpu endian by Michael Ellerman.

 - Large series from Wei Yang to implement SRIOV, reviewed and acked by
   Bjorn.

 - A fix for the OPAL sensor driver from Cédric Le Goater.

 - Fixes to get STRICT_MM_TYPECHECKS building again by Michael Ellerman.

 - Large series from Daniel Axtens to make our PCI hooks per PHB rather
   than per machine.

 - Small patch from Sam Bobroff to explicitly abort non-suspended
   transactions on syscalls, plus a test to exercise it.

 - Numerous reworks and fixes for the 24x7 PMU from Sukadev Bhattiprolu.

 - Small patch to enable the hard lockup detector from Anton Blanchard.

 - Fix from Dave Olson for missing L2 cache information on some CPUs.

 - Some fixes from Michael Ellerman to get Cell machines booting again.

 - Freescale updates from Scott: Highlights include BMan device tree
   nodes, an MSI erratum workaround, a couple minor performance
   improvements, config updates, and misc fixes/cleanup.

* tag 'powerpc-4.1-1' of git://git.kernel.org/pub/scm/linux/kernel/git/mpe/linux: (196 commits)
  powerpc/powermac: Fix build error seen with powermac smp builds
  powerpc/pseries: Fix compile of memory hotplug without CONFIG_MEMORY_HOTREMOVE
  powerpc: Remove PPC32 code from pseries specific find_and_init_phbs()
  powerpc/cell: Fix iommu breakage caused by controller_ops change
  powerpc/eeh: Fix crash in eeh_add_device_early() on Cell
  powerpc/perf: Cap 64bit userspace backtraces to PERF_MAX_STACK_DEPTH
  powerpc/perf/hv-24x7: Fail 24x7 initcall if create_events_from_catalog() fails
  powerpc/pseries: Correct memory hotplug locking
  powerpc: Fix missing L2 cache size in /sys/devices/system/cpu
  powerpc: Add ppc64 hard lockup detector support
  oprofile: Disable oprofile NMI timer on ppc64
  powerpc/perf/hv-24x7: Add missing put_cpu_var()
  powerpc/perf/hv-24x7: Break up single_24x7_request
  powerpc/perf/hv-24x7: Define update_event_count()
  powerpc/perf/hv-24x7: Whitespace cleanup
  powerpc/perf/hv-24x7: Define add_event_to_24x7_request()
  powerpc/perf/hv-24x7: Rename hv_24x7_event_update
  powerpc/perf/hv-24x7: Move debug prints to separate function
  powerpc/perf/hv-24x7: Drop event_24x7_request()
  powerpc/perf/hv-24x7: Use pr_devel() to log message
  ...

Conflicts:
	tools/testing/selftests/powerpc/Makefile
	tools/testing/selftests/powerpc/tm/Makefile
2015-04-16 13:53:32 -05:00
David Howells 2b0143b5c9 VFS: normal filesystems (and lustre): d_inode() annotations
that's the bulk of filesystem drivers dealing with inodes of their own

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-04-15 15:06:57 -04:00
Hari Bathini ae011d2e48 pstore: Add pstore type id for PPC64 opal nvram partition
This patch adds a new PPC64 partition type to be used for opal
specific nvram partition. A new partition type is needed as none
of the existing type matches this partition type.

Signed-off-by: Hari Bathini <hbathini@linux.vnet.ibm.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2015-03-23 14:06:10 +11:00
Wang Long 62f269ef81 pstore: Fix the ramoops module parameters update
In the function ramoops_probe, the console_size, pmsg_size,
ftrace_size may be update because the value is not the power
of two. We should update the module parameter variables
as well so they are visible through /sys/module/ramoops/parameters
correctly.

Signed-off-by: Wang Long <long.wanglong@huawei.com>
Acked-by: Mark Salyzyn <salyzyn@android.com>
Acked-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Tony Luck <tony.luck@intel.com>
2015-03-16 11:14:10 -07:00
alex chen a6b8978c54 pstore: Fix sprintf format specifier in pstore_dump()
We should use sprintf format specifier "%u" instead of "%d" for
argument of type 'unsigned int' in pstore_dump().

Signed-off-by: Alex Chen <alex.chen@huawei.com>
Reviewed-by: Joseph Qi <joseph.qi@huawei.com>
Acked-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Tony Luck <tony.luck@intel.com>
2015-01-16 16:01:29 -08:00
Mark Salyzyn 9d5438f462 pstore: Add pmsg - user-space accessible pstore object
A secured user-space accessible pstore object. Writes
to /dev/pmsg0 are appended to the buffer, on reboot
the persistent contents are available in
/sys/fs/pstore/pmsg-ramoops-[ID].

One possible use is syslogd, or other daemon, can
write messages, then on reboot provides a means to
triage user-space activities leading up to a panic
as a companion to the pstore dmesg or console logs.

Signed-off-by: Mark Salyzyn <salyzyn@android.com>
Acked-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Tony Luck <tony.luck@intel.com>
2015-01-16 16:01:10 -08:00
Mark Salyzyn f44f96528a pstore: Handle zero-sized prz in series
ramoops_pstore_read fails to return the next in a prz
series after first zero-sized entry, not venturing to
the next non-zero entry.

Signed-off-by: Mark Salyzyn <salyzyn@android.com>
Acked-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Tony Luck <tony.luck@intel.com>
2015-01-16 15:47:23 -08:00
Mark Salyzyn ff6bf6e802 pstore: Remove superfluous memory size check
All previous checks will fail with error if memory size
is not sufficient to register a zone, so this legacy
check has become redundant.

Signed-off-by: Mark Salyzyn <salyzyn@android.com>
Acked-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Tony Luck <tony.luck@intel.com>
2015-01-16 15:45:46 -08:00
Mark Salyzyn dbaffde764 pstore: Use scnprintf() in pstore_mkfile()
No guarantees that the names will not exceed the
name buffer with future adjustments.

Signed-off-by: Mark Salyzyn <salyzyn@android.com>
Acked-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Tony Luck <tony.luck@intel.com>
2015-01-16 15:30:50 -08:00
Linus Torvalds e6b5be2be4 Driver core patches for 3.19-rc1
Here's the set of driver core patches for 3.19-rc1.
 
 They are dominated by the removal of the .owner field in platform
 drivers.  They touch a lot of files, but they are "simple" changes, just
 removing a line in a structure.
 
 Other than that, a few minor driver core and debugfs changes.  There are
 some ath9k patches coming in through this tree that have been acked by
 the wireless maintainers as they relied on the debugfs changes.
 
 Everything has been in linux-next for a while.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'driver-core-3.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core

Pull driver core update from Greg KH:
 "Here's the set of driver core patches for 3.19-rc1.

  They are dominated by the removal of the .owner field in platform
  drivers.  They touch a lot of files, but they are "simple" changes,
  just removing a line in a structure.

  Other than that, a few minor driver core and debugfs changes.  There
  are some ath9k patches coming in through this tree that have been
  acked by the wireless maintainers as they relied on the debugfs
  changes.

  Everything has been in linux-next for a while"

* tag 'driver-core-3.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (324 commits)
  Revert "ath: ath9k: use debugfs_create_devm_seqfile() helper for seq_file entries"
  fs: debugfs: add forward declaration for struct device type
  firmware class: Deletion of an unnecessary check before the function call "vunmap"
  firmware loader: fix hung task warning dump
  devcoredump: provide a one-way disable function
  device: Add dev_<level>_once variants
  ath: ath9k: use debugfs_create_devm_seqfile() helper for seq_file entries
  ath: use seq_file api for ath9k debugfs files
  debugfs: add helper function to create device related seq_file
  drivers/base: cacheinfo: remove noisy error boot message
  Revert "core: platform: add warning if driver has no owner"
  drivers: base: support cpu cache information interface to userspace via sysfs
  drivers: base: add cpu_device_create to support per-cpu devices
  topology: replace custom attribute macros with standard DEVICE_ATTR*
  cpumask: factor out show_cpumap into separate helper function
  driver core: Fix unbalanced device reference in drivers_probe
  driver core: fix race with userland in device_add()
  sysfs/kernfs: make read requests on pre-alloc files use the buffer.
  sysfs/kernfs: allow attributes to request write buffer be pre-allocated.
  fs: sysfs: return EGBIG on write if offset is larger than file size
  ...
2014-12-14 16:10:09 -08:00
Tony Lindgren 027bc8b082 pstore-ram: Allow optional mapping with pgprot_noncached
On some ARMs the memory can be mapped pgprot_noncached() and still
be working for atomic operations. As pointed out by Colin Cross
<ccross@android.com>, in some cases you do want to use
pgprot_noncached() if the SoC supports it to see a debug printk
just before a write hanging the system.

On ARMs, the atomic operations on strongly ordered memory are
implementation defined. So let's provide an optional kernel parameter
for configuring pgprot_noncached(), and use pgprot_writecombine() by
default.

Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Rob Herring <robherring2@gmail.com>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Anton Vorontsov <anton@enomsg.org>
Cc: Colin Cross <ccross@android.com>
Cc: Olof Johansson <olof@lixom.net>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: stable@vger.kernel.org
Acked-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
2014-12-11 13:38:31 -08:00
Rob Herring 7ae9cb8193 pstore-ram: Fix hangs by using write-combine mappings
Currently trying to use pstore on at least ARMs can hang as we're
mapping the peristent RAM with pgprot_noncached().

On ARMs, pgprot_noncached() will actually make the memory strongly
ordered, and as the atomic operations pstore uses are implementation
defined for strongly ordered memory, they may not work. So basically
atomic operations have undefined behavior on ARM for device or strongly
ordered memory types.

Let's fix the issue by using write-combine variants for mappings. This
corresponds to normal, non-cacheable memory on ARM. For many other
architectures, this change does not change the mapping type as by
default we have:

#define pgprot_writecombine pgprot_noncached

The reason why pgprot_noncached() was originaly used for pstore
is because Colin Cross <ccross@android.com> had observed lost
debug prints right before a device hanging write operation on some
systems. For the platforms supporting pgprot_noncached(), we can
add a an optional configuration option to support that. But let's
get pstore working first before adding new features.

Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Anton Vorontsov <cbouatmailru@gmail.com>
Cc: Colin Cross <ccross@android.com>
Cc: Olof Johansson <olof@lixom.net>
Cc: linux-kernel@vger.kernel.org
Cc: stable@vger.kernel.org
Acked-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Rob Herring <rob.herring@calxeda.com>
[tony@atomide.com: updated description]
Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
2014-12-11 13:35:49 -08:00
Sebastian Schmidt 68c4a4f8ab pstore: Honor dmesg_restrict sysctl on dmesg dumps
When the kernel.dmesg_restrict restriction is in place, only users with
CAP_SYSLOG should be able to access crash dumps (like: attacker is
trying to exploit a bug, watchdog reboots, attacker can happily read
crash dumps and logs).

This puts the restriction on console-* types as well as sensitive
information could have been leaked there.

Other log types are unaffected.

Signed-off-by: Sebastian Schmidt <yath@yath.de>
Acked-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Tony Luck <tony.luck@intel.com>
2014-11-05 09:59:48 -08:00
Ben Zhang a28726b4fb pstore/ram: Strip ramoops header for correct decompression
pstore compression/decompression was added during 3.12.
The ramoops driver prepends a "====timestamp.timestamp-C|D\n"
header to the compressed record before handing it over to pstore
driver which doesn't know about the header. In pstore_decompress(),
the pstore driver reads the first "==" as a zlib header, so the
decompression always fails. For example, this causes the driver
to write /dev/pstore/dmesg-ramoops-0.enc.z instead of
/dev/pstore/dmesg-ramoops-0.

This patch makes the ramoops driver remove the header before
pstore decompression.

Signed-off-by: Ben Zhang <benzh@chromium.org>
Acked-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Tony Luck <tony.luck@intel.com>
2014-11-05 09:58:17 -08:00
Wolfram Sang 75c43e0493 pstore: drop owner assignment from platform_drivers
A platform_driver does not need to set an owner, it will be populated by the
driver core.

Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-10-20 16:21:57 +02:00
Valdis Kletnieks d4bf205da6 pstore: Fix duplicate {console,ftrace}-efi entries
The pstore filesystem still creates duplicate filename/inode pairs for
some pstore types.  Add the id to the filename to prevent that.

Before patch:

[/sys/fs/pstore] ls -li
total 0
1250 -r--r--r--. 1 root root 67 Sep 29 17:09 console-efi
1250 -r--r--r--. 1 root root 67 Sep 29 17:09 console-efi
1250 -r--r--r--. 1 root root 67 Sep 29 17:09 console-efi
1250 -r--r--r--. 1 root root 67 Sep 29 17:09 console-efi
1250 -r--r--r--. 1 root root 67 Sep 29 17:09 console-efi
1250 -r--r--r--. 1 root root 67 Sep 29 17:09 console-efi
1250 -r--r--r--. 1 root root 67 Sep 29 17:09 console-efi
1250 -r--r--r--. 1 root root 67 Sep 29 17:09 console-efi
1250 -r--r--r--. 1 root root 67 Sep 29 17:09 console-efi

After:

[/sys/fs/pstore] ls -li
total 0
1232 -r--r--r--. 1 root root 148 Sep 29 17:09 console-efi-141202499100000
1231 -r--r--r--. 1 root root  67 Sep 29 17:09 console-efi-141202499200000
1230 -r--r--r--. 1 root root 148 Sep 29 17:44 console-efi-141202705400000
1229 -r--r--r--. 1 root root  67 Sep 29 17:44 console-efi-141202705500000
1228 -r--r--r--. 1 root root  67 Sep 29 20:42 console-efi-141203772600000
1227 -r--r--r--. 1 root root 148 Sep 29 23:42 console-efi-141204854900000
1226 -r--r--r--. 1 root root  67 Sep 29 23:42 console-efi-141204855000000
1225 -r--r--r--. 1 root root 148 Sep 29 23:59 console-efi-141204954200000
1224 -r--r--r--. 1 root root  67 Sep 29 23:59 console-efi-141204954400000

Signed-off-by: Valdis Kletnieks <valdis.kletnieks@vt.edu>
Acked-by: Kees Cook <keescook@chromium.org>
Cc: stable@vger.kernel.org # 3.6+
Signed-off-by: Tony Luck <tony.luck@intel.com>
2014-10-15 13:51:33 -07:00
Fabian Frederick b8f52d89c0 fs/pstore/ram_core.c: replace count*size kmalloc by kmalloc_array
kmalloc_array manages count*sizeof overflow.

Signed-off-by: Fabian Frederick <fabf@skynet.be>
Cc: Anton Vorontsov <anton@enomsg.org>
Cc: Colin Cross <ccross@android.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-08-08 15:57:25 -07:00
Fabian Frederick ef74885353 fs/pstore: logging clean-up
- Define pr_fmt in plateform.c and ram_core.c for global prefix.

- Coalesce format fragments.

- Separate format/arguments on lines > 80 characters.

Note: Some pr_foo() were initially declared without prefix and therefore
this could break existing log analyzer.

[akpm@linux-foundation.org: missed a couple of prefix removals]
Signed-off-by: Fabian Frederick <fabf@skynet.be>
Cc: Joe Perches <joe@perches.com>
Cc: Anton Vorontsov <anton@enomsg.org>
Cc: Colin Cross <ccross@android.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-06-06 16:08:13 -07:00
Linus Torvalds 24e7ea3bea Major changes for 3.14 include support for the newly added ZERO_RANGE
and COLLAPSE_RANGE fallocate operations, and scalability improvements
 in the jbd2 layer and in xattr handling when the extended attributes
 spill over into an external block.
 
 Other than that, the usual clean ups and minor bug fixes.
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Merge tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4

Pull ext4 updates from Ted Ts'o:
 "Major changes for 3.14 include support for the newly added ZERO_RANGE
  and COLLAPSE_RANGE fallocate operations, and scalability improvements
  in the jbd2 layer and in xattr handling when the extended attributes
  spill over into an external block.

  Other than that, the usual clean ups and minor bug fixes"

* tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4: (42 commits)
  ext4: fix premature freeing of partial clusters split across leaf blocks
  ext4: remove unneeded test of ret variable
  ext4: fix comment typo
  ext4: make ext4_block_zero_page_range static
  ext4: atomically set inode->i_flags in ext4_set_inode_flags()
  ext4: optimize Hurd tests when reading/writing inodes
  ext4: kill i_version support for Hurd-castrated file systems
  ext4: each filesystem creates and uses its own mb_cache
  fs/mbcache.c: doucple the locking of local from global data
  fs/mbcache.c: change block and index hash chain to hlist_bl_node
  ext4: Introduce FALLOC_FL_ZERO_RANGE flag for fallocate
  ext4: refactor ext4_fallocate code
  ext4: Update inode i_size after the preallocation
  ext4: fix partial cluster handling for bigalloc file systems
  ext4: delete path dealloc code in ext4_ext_handle_uninitialized_extents
  ext4: only call sync_filesystm() when remounting read-only
  fs: push sync_filesystem() down to the file system's remount_fs()
  jbd2: improve error messages for inconsistent journal heads
  jbd2: minimize region locked by j_list_lock in jbd2_journal_forget()
  jbd2: minimize region locked by j_list_lock in journal_get_create_access()
  ...
2014-04-04 15:39:39 -07:00
Liu ShuoX e32634f5d5 pstore: Fix memory leak when decompress using big_oops_buf
After sucessful decompressing, the buffer which pointed by 'buf' will be
lost as 'buf' is overwrite by 'big_oops_buf' and will never be freed.

Signed-off-by: Liu ShuoX <shuox.liu@intel.com>
Acked-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Tony Luck <tony.luck@intel.com>
2014-03-17 14:14:03 -07:00