Modern kernel callback systems pass the structure associated with a
given callback to the callback function. The timer callback remains one
of the legacy cases where an arbitrary unsigned long argument continues
to be passed as the callback argument. This has several problems:
- This bloats the timer_list structure with a normally redundant
.data field.
- No type checking is being performed, forcing callbacks to do
explicit type casts of the unsigned long argument into the object
that was passed, rather than using container_of(), as done in most
of the other callback infrastructure.
- Neighboring buffer overflows can overwrite both the .function and
the .data field, providing attackers with a way to elevate from a buffer
overflow into a simplistic ROP-like mechanism that allows calling
arbitrary functions with a controlled first argument.
- For future Control Flow Integrity work, this creates a unique function
prototype for timer callbacks, instead of allowing them to continue to
be clustered with other void functions that take a single unsigned long
argument.
This adds a new timer initialization API, which will ultimately replace
the existing setup_timer(), setup_{deferrable,pinned,etc}_timer() family,
named timer_setup() (to mirror hrtimer_setup(), making instances of its
use much easier to grep for).
In order to support the migration of existing timers into the new
callback arguments, timer_setup() casts its arguments to the existing
legacy types, and explicitly passes the timer pointer as the legacy
data argument. Once all setup_*timer() callers have been replaced with
timer_setup(), the casts can be removed, and the data argument can be
dropped with the timer expiration code changed to just pass the timer
to the callback directly.
Since the regular pattern of using container_of() during local variable
declaration repeats the need for the variable type declaration
to be included, this adds a helper modeled after other from_*()
helpers that wrap container_of(), named from_timer(). This helper uses
typeof(*variable), removing the type redundancy and minimizing the need
for line wraps in forthcoming conversions from "unsigned data long" to
"struct timer_list *" in the timer callbacks:
-void callback(unsigned long data)
+void callback(struct timer_list *t)
{
- struct some_data_structure *local = (struct some_data_structure *)data;
+ struct some_data_structure *local = from_timer(local, t, timer);
Finally, in order to support the handful of timer users that perform
open-coded assignments of the .function (and .data) fields, provide
cast macros (TIMER_FUNC_TYPE and TIMER_DATA_TYPE) that can be used
temporarily. Once conversion has been completed, these can be globally
trivially removed.
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20170928133817.GA113410@beast
Change-Id: Ie5af397a7702c2ed9f9cda23e3dcc04708c057dc
This change affects to the OSD driver, drivers/amlogic/media/osd/osd_fb.c, to enable
soft cursor instead of OSD cursor.
Signed-off-by: Dongjin Kim <tobetter@gmail.com>
Change-Id: Ic4af0037579b5b62c4df7b29a05d1cceec0cd9cf
This patch adds to new attribute 'pwm1_enable' to change the fan speed
control method as documented in 'Documentation/hwmon/sysfs-interface'.
Signed-off-by: Dongjin Kim <tobetter@gmail.com>
Change-Id: I19094d60e928d6c3ce226d319e75a35ecbd3ae52
The existing force64b routine might not work properly under specific
conditions. This patch fixes that bug of 64 bits per word and forces
use that option. It will improve SPI performance significantly.
Signed-off-by: Deokgyu Yang <secugyu@gmail.com>
Change-Id: I85a58d425303ea1765b7b83ee5dd5f0a7f4203fc
- The PWM's configuration is difference between the n2 and c4. So
separate configuration and placed to the device tree overlays.
Change-Id: Ia870ce6ea4404c8bc7028ae7f1cc72174406ed27
[1] GPIOAO_2 is tied to control USB 2.0 host power
[2] USB 3.0 PHY must be disabled exclusively for PCIe.
Signed-off-by: Dongjin Kim <tobetter@gmail.com>
Change-Id: I340ca69f6da448a441ed75c506ea569947a581c4
commit 437ef802e0 upstream.
There are 2 problems with it:
1. "<" vs expected "<<"
2. the shift number is an IOMMU page number mask, not an address
mask as the IOMMU page shift is missing.
This did not hit us before f1565c24b5 ("powerpc: use the generic
dma_ops_bypass mode") because we had additional code to handle bypass
mask so this chunk (almost?) never executed.However there were
reports that aacraid does not work with "iommu=nobypass".
After f1565c24b5, aacraid (and probably others which call
dma_get_required_mask() before setting the mask) was unable to enable
64bit DMA and fall back to using IOMMU which was known not to work,
one of the problems is double free of an IOMMU page.
This fixes DMA for aacraid, both with and without "iommu=nobypass" in
the kernel command line. Verified with "stress-ng -d 4".
Fixes: 6a5c7be5e4 ("powerpc: Override dma_get_required_mask by platform hook and ops")
Cc: stable@vger.kernel.org # v3.2+
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200908015106.79661-1-aik@ozlabs.ru
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 29231826f3 upstream.
The CRC calculation done by genksyms is triggered when the parser hits
EXPORT_SYMBOL*() macros. At this point, genksyms recursively expands the
types of the function parameters, and uses that as the input for the CRC
calculation. In the case of forward-declared structs, the type expands
to 'UNKNOWN'. Following this, it appears that the result of the
expansion of each type is cached somewhere, and seems to be re-used
when/if the same type is seen again for another exported symbol in the
same C file.
Unfortunately, this can cause CRC 'stability' issues when a struct
definition becomes visible in the middle of a C file. For example, let's
assume code with the following pattern:
struct foo;
int bar(struct foo *arg)
{
/* Do work ... */
}
EXPORT_SYMBOL_GPL(bar);
/* This contains struct foo's definition */
#include "foo.h"
int baz(struct foo *arg)
{
/* Do more work ... */
}
EXPORT_SYMBOL_GPL(baz);
Here, baz's CRC will be computed using the expansion of struct foo that
was cached after bar's CRC calculation ('UNKOWN' here). But if
EXPORT_SYMBOL_GPL(bar) is removed from the file (because of e.g. symbol
trimming using CONFIG_TRIM_UNUSED_KSYMS), struct foo will be expanded
late, during baz's CRC calculation, which now has visibility over the
full struct definition, hence resulting in a different CRC for baz.
The proper fix for this certainly is in genksyms, but that will take me
some time to get right. In the meantime, we have seen one occurrence of
this in the ehci-hcd code which hits this problem because of the way it
includes C files halfway through the code together with an unlucky mix
of symbol trimming.
In order to workaround this, move the include done in ehci-hub.c early
in ehci-hcd.c, hence making sure the struct definitions are visible to
the entire file. This improves CRC stability of the ehci-hcd exports
even when symbol trimming is enabled.
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Quentin Perret <qperret@google.com>
Link: https://lore.kernel.org/r/20200916171825.3228122-1-qperret@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 64c194c007 ]
mtk_ddp_comp_init() is called in a loop in mtk_drm_probe(), if it
fail, previous successive init component is not proccessed.
Thus uninitialize valid component and put their device if component
init failed.
Fixes: 119f517362 ("drm/mediatek: Add DRM Driver for Mediatek SoC MT8173.")
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Signed-off-by: Chun-Kuang Hu <chunkuang.hu@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit b959b97860 ]
On A20R machines the interrupt pending bits in cause register need to be
updated by requesting the chipset to do it. This needs to be done to
find the interrupt cause and after interrupt service. In
commit 0b888c7f3a ("MIPS: SNI: Convert to new irq_chip functions") the
function to do after service update got lost, which caused spurious
interrupts.
Fixes: 0b888c7f3a ("MIPS: SNI: Convert to new irq_chip functions")
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
