linux-stable.git/drivers/base, branch linux-3.10.y

PM / Domains: Fix unsafe iteration over modified list of device links

2017-11-01T21:12:43+00:00

commit c6e83cac3eda5f7dd32ee1453df2f7abb5c6cd46 upstream.

pm_genpd_remove_subdomain() iterates over domain's master_links list and
removes matching element thus it has to use safe version of list
iteration.

Fixes: f721889ff65a ("PM / Domains: Support for generic I/O PM domains (v8)")
Cc: 3.1+  # 3.1+
Signed-off-by: Krzysztof Kozlowski 
Acked-by: Ulf Hansson 
Signed-off-by: Rafael J. Wysocki 
Signed-off-by: Willy Tarreau

driver core: fix race between creating/querying glue dir and its cleanup

2017-02-10T10:03:30+00:00

commit cebf8fd16900fdfd58c0028617944f808f97fe50 upstream.

The global mutex of 'gdp_mutex' is used to serialize creating/querying
glue dir and its cleanup. Turns out it isn't a perfect way because
part(kobj_kset_leave()) of the actual cleanup action() is done inside
the release handler of the glue dir kobject. That means gdp_mutex has
to be held before releasing the last reference count of the glue dir
kobject.

This patch moves glue dir's cleanup after kobject_del() in device_del()
for avoiding the race.

Cc: Yijing Wang 
Reported-by: Chandra Sekhar Lingutla 
Signed-off-by: Ming Lei 
Signed-off-by: Greg Kroah-Hartman 
Signed-off-by: Willy Tarreau

driver core: Delete an unnecessary check before the function call "put_device"

2017-02-10T10:03:30+00:00

commit 5f0163a5ee9cc7c59751768bdfd94a73186debba upstream.

The put_device() function tests whether its argument is NULL and then
returns immediately. Thus the test around the call is not needed.

This issue was detected by using the Coccinelle software.

Signed-off-by: Markus Elfring 
Signed-off-by: Greg Kroah-Hartman 
[wt: backported only to ease next patch as suggested by Jiri]

Signed-off-by: Willy Tarreau

base: make module_create_drivers_dir race-free

2016-08-27T09:40:24+00:00

commit 7e1b1fc4dabd6ec8e28baa0708866e13fa93c9b3 upstream.

Modules which register drivers via standard path (driver_register) in
parallel can cause a warning:
WARNING: CPU: 2 PID: 3492 at ../fs/sysfs/dir.c:31 sysfs_warn_dup+0x62/0x80
sysfs: cannot create duplicate filename '/module/saa7146/drivers'
Modules linked in: hexium_gemini(+) mxb(+) ...
...
Call Trace:
...
 [] sysfs_warn_dup+0x62/0x80
 [] sysfs_create_dir_ns+0x77/0x90
 [] kobject_add_internal+0xb4/0x340
 [] kobject_add+0x68/0xb0
 [] kobject_create_and_add+0x31/0x70
 [] module_add_driver+0xc3/0xd0
 [] bus_add_driver+0x154/0x280
 [] driver_register+0x60/0xe0
 [] __pci_register_driver+0x60/0x70
 [] saa7146_register_extension+0x64/0x90 [saa7146]
 [] hexium_init_module+0x11/0x1000 [hexium_gemini]
...

As can be (mostly) seen, driver_register causes this call sequence:
  -> bus_add_driver
    -> module_add_driver
      -> module_create_drivers_dir
The last one creates "drivers" directory in /sys/module/<...>. When
this is done in parallel, the directory is attempted to be created
twice at the same time.

This can be easily reproduced by loading mxb and hexium_gemini in
parallel:
while :; do
  modprobe mxb &
  modprobe hexium_gemini
  wait
  rmmod mxb hexium_gemini saa7146_vv saa7146
done

saa7146 calls pci_register_driver for both mxb and hexium_gemini,
which means /sys/module/saa7146/drivers is to be created for both of
them.

Fix this by a new mutex in module_create_drivers_dir which makes the
test-and-create "drivers" dir atomic.

I inverted the condition and removed 'return' to avoid multiple
unlocks or a goto.

Signed-off-by: Jiri Slaby 
Fixes: fe480a2675ed (Modules: only add drivers/ direcory if needed)
Cc: v2.6.21+ 
Signed-off-by: Greg Kroah-Hartman 
Signed-off-by: Willy Tarreau

regmap: debugfs: Don't bother actually printing when calculating max length

2015-10-22T21:37:51+00:00

commit 176fc2d5770a0990eebff903ba680d2edd32e718 upstream.

The in kernel snprintf() will conveniently return the actual length of
the printed string even if not given an output beffer at all so just do
that rather than relying on the user to pass in a suitable buffer,
ensuring that we don't need to worry if the buffer was truncated due to
the size of the buffer passed in.

Reported-by: Rasmus Villemoes 
Signed-off-by: Mark Brown 
Signed-off-by: Greg Kroah-Hartman

regmap: debugfs: Ensure we don't underflow when printing access masks

2015-10-22T21:37:51+00:00

commit b763ec17ac762470eec5be8ebcc43e4f8b2c2b82 upstream.

If a read is attempted which is smaller than the line length then we may
underflow the subtraction we're doing with the unsigned size_t type so
move some of the calculation to be additions on the right hand side
instead in order to avoid this.

Reported-by: Rasmus Villemoes 
Signed-off-by: Mark Brown 
Cc: stable@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman

drivercore: Fix unregistration path of platform devices

2015-09-21T17:00:10+00:00

commit 7f5dcaf1fdf289767a126a0a5cc3ef39b5254b06 upstream.

The unregister path of platform_device is broken. On registration, it
will register all resources with either a parent already set, or
type==IORESOURCE_{IO,MEM}. However, on unregister it will release
everything with type==IORESOURCE_{IO,MEM}, but ignore the others. There
are also cases where resources don't get registered in the first place,
like with devices created by of_platform_populate()*.

Fix the unregister path to be symmetrical with the register path by
checking the parent pointer instead of the type field to decide which
resources to unregister. This is safe because the upshot of the
registration path algorithm is that registered resources have a parent
pointer, and non-registered resources do not.

* It can be argued that of_platform_populate() should be registering
  it's resources, and they argument has some merit. However, there are
  quite a few platforms that end up broken if we try to do that due to
  overlapping resources in the device tree. Until that is fixed, we need
  to solve the immediate problem.

Cc: Pantelis Antoniou 
Cc: Wolfram Sang 
Cc: Rob Herring 
Cc: Greg Kroah-Hartman 
Cc: Ricardo Ribalda Delgado 
Signed-off-by: Grant Likely 
Tested-by: Ricardo Ribalda Delgado 
Tested-by: Wolfram Sang 
Signed-off-by: Rob Herring 
Signed-off-by: Greg Kroah-Hartman

devres: fix devres_get()

2015-09-21T17:00:09+00:00

commit 64526370d11ce8868ca495723d595b61e8697fbf upstream.

Currently, devres_get() passes devres_free() the pointer to devres,
but devres_free() should be given with the pointer to resource data.

Fixes: 9ac7849e35f7 ("devres: device resource management")
Signed-off-by: Masahiro Yamada 
Acked-by: Tejun Heo 
Signed-off-by: Greg Kroah-Hartman

Fix firmware loader uevent buffer NULL pointer dereference

2015-08-03T16:29:47+00:00

commit 6f957724b94cb19f5c1c97efd01dd4df8ced323c upstream.

The firmware class uevent function accessed the "fw_priv->buf" buffer
without the proper locking and testing for NULL.  This is an old bug
(looks like it goes back to 2012 and commit 1244691c73b2: "firmware
loader: introduce firmware_buf"), but for some reason it's triggering
only now in 4.2-rc1.

Shuah Khan is trying to bisect what it is that causes this to trigger
more easily, but in the meantime let's just fix the bug since others are
hitting it too (at least Ingo reports having seen it as well).

Reported-and-tested-by: Shuah Khan 
Acked-by: Ming Lei 
Signed-off-by: Linus Torvalds 
Signed-off-by: Greg Kroah-Hartman

regmap: Fix regmap_bulk_read in BE mode

2015-08-03T16:29:41+00:00

commit 15b8d2c41fe5839582029f65c5f7004db451cc2b upstream.

In big endian mode regmap_bulk_read gives incorrect data
for byte reads.

This is because memcpy of a single byte from an address
after full word read gives different results when
endianness differs. ie. we get little-end in LE and big-end in BE.

Signed-off-by: Arun Chandran 
Signed-off-by: Mark Brown 
Signed-off-by: Greg Kroah-Hartman