<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux-stable.git/drivers/acpi, branch v4.9.306</title>
<subtitle>Linux kernel stable tree</subtitle>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/'/>
<entry>
<title>ACPICA: Executer: Fix the REFCLASS_REFOF case in acpi_ex_opcode_1A_0T_1R()</title>
<updated>2022-01-27T07:47:38+00:00</updated>
<author>
<name>Rafael J. Wysocki</name>
<email>rafael.j.wysocki@intel.com</email>
</author>
<published>2021-12-22T16:31:05+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=8bb6aa75202437a956e6261418609baa7d27e847'/>
<id>8bb6aa75202437a956e6261418609baa7d27e847</id>
<content type='text'>
[ Upstream commit 24ea5f90ec9548044a6209685c5010edd66ffe8f ]

ACPICA commit d984f12041392fa4156b52e2f7e5c5e7bc38ad9e

If Operand[0] is a reference of the ACPI_REFCLASS_REFOF class,
acpi_ex_opcode_1A_0T_1R () calls acpi_ns_get_attached_object () to
obtain return_desc which may require additional resolution with
the help of acpi_ex_read_data_from_field (). If the latter fails,
the reference counter of the original return_desc is decremented
which is incorrect, because acpi_ns_get_attached_object () does not
increment the reference counter of the object returned by it.

This issue may lead to premature deletion of the attached object
while it is still attached and a use-after-free and crash in the
host OS.  For example, this may happen when on evaluation of ref_of()
a local region field where there is no registered handler for the
given Operation Region.

Fix it by making acpi_ex_opcode_1A_0T_1R () return Status right away
after a acpi_ex_read_data_from_field () failure.

Link: https://github.com/acpica/acpica/commit/d984f120
Link: https://github.com/acpica/acpica/pull/685
Reported-by: Lenny Szubowicz &lt;lszubowi@redhat.com&gt;
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
Signed-off-by: Bob Moore &lt;robert.moore@intel.com&gt;
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 24ea5f90ec9548044a6209685c5010edd66ffe8f ]

ACPICA commit d984f12041392fa4156b52e2f7e5c5e7bc38ad9e

If Operand[0] is a reference of the ACPI_REFCLASS_REFOF class,
acpi_ex_opcode_1A_0T_1R () calls acpi_ns_get_attached_object () to
obtain return_desc which may require additional resolution with
the help of acpi_ex_read_data_from_field (). If the latter fails,
the reference counter of the original return_desc is decremented
which is incorrect, because acpi_ns_get_attached_object () does not
increment the reference counter of the object returned by it.

This issue may lead to premature deletion of the attached object
while it is still attached and a use-after-free and crash in the
host OS.  For example, this may happen when on evaluation of ref_of()
a local region field where there is no registered handler for the
given Operation Region.

Fix it by making acpi_ex_opcode_1A_0T_1R () return Status right away
after a acpi_ex_read_data_from_field () failure.

Link: https://github.com/acpica/acpica/commit/d984f120
Link: https://github.com/acpica/acpica/pull/685
Reported-by: Lenny Szubowicz &lt;lszubowi@redhat.com&gt;
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
Signed-off-by: Bob Moore &lt;robert.moore@intel.com&gt;
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>ACPICA: Utilities: Avoid deleting the same object twice in a row</title>
<updated>2022-01-27T07:47:38+00:00</updated>
<author>
<name>Rafael J. Wysocki</name>
<email>rafael.j.wysocki@intel.com</email>
</author>
<published>2021-12-22T16:29:45+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=922865cf4825215559068d8f17fbe5a4513c087d'/>
<id>922865cf4825215559068d8f17fbe5a4513c087d</id>
<content type='text'>
[ Upstream commit 1cdfe9e346b4c5509ffe19ccde880fd259d9f7a3 ]

ACPICA commit c11af67d8f7e3d381068ce7771322f2b5324d687

If original_count is 0 in acpi_ut_update_ref_count (),
acpi_ut_delete_internal_obj () is invoked for the target object, which is
incorrect, because that object has been deleted once already and the
memory allocated to store it may have been reclaimed and allocated
for a different purpose by the host OS.  Moreover, a confusing debug
message following the "Reference Count is already zero, cannot
decrement" warning is printed in that case.

To fix this issue, make acpi_ut_update_ref_count () return after finding
that original_count is 0 and printing the above warning.

Link: https://github.com/acpica/acpica/commit/c11af67d
Link: https://github.com/acpica/acpica/pull/652
Reported-by: Mark Asselstine &lt;mark.asselstine@windriver.com&gt;
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
Signed-off-by: Bob Moore &lt;robert.moore@intel.com&gt;
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 1cdfe9e346b4c5509ffe19ccde880fd259d9f7a3 ]

ACPICA commit c11af67d8f7e3d381068ce7771322f2b5324d687

If original_count is 0 in acpi_ut_update_ref_count (),
acpi_ut_delete_internal_obj () is invoked for the target object, which is
incorrect, because that object has been deleted once already and the
memory allocated to store it may have been reclaimed and allocated
for a different purpose by the host OS.  Moreover, a confusing debug
message following the "Reference Count is already zero, cannot
decrement" warning is printed in that case.

To fix this issue, make acpi_ut_update_ref_count () return after finding
that original_count is 0 and printing the above warning.

Link: https://github.com/acpica/acpica/commit/c11af67d
Link: https://github.com/acpica/acpica/pull/652
Reported-by: Mark Asselstine &lt;mark.asselstine@windriver.com&gt;
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
Signed-off-by: Bob Moore &lt;robert.moore@intel.com&gt;
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>ACPI: PMIC: Fix intel_pmic_regs_handler() read accesses</title>
<updated>2021-11-26T10:48:39+00:00</updated>
<author>
<name>Hans de Goede</name>
<email>hdegoede@redhat.com</email>
</author>
<published>2021-10-31T15:31:35+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=e8b8ac3bc00a2284b7c220c6ca972e9b8e996e27'/>
<id>e8b8ac3bc00a2284b7c220c6ca972e9b8e996e27</id>
<content type='text'>
[ Upstream commit 009a789443fe4c8e6b1ecb7c16b4865c026184cd ]

The handling of PMIC register reads through writing 0 to address 4
of the OpRegion is wrong. Instead of returning the read value
through the value64, which is a no-op for function == ACPI_WRITE calls,
store the value and then on a subsequent function == ACPI_READ with
address == 3 (the address for the value field of the OpRegion)
return the stored value.

This has been tested on a Xiaomi Mi Pad 2 and makes the ACPI battery dev
there mostly functional (unfortunately there are still other issues).

Here are the SET() / GET() functions of the PMIC ACPI device,
which use this OpRegion, which clearly show the new behavior to
be correct:

OperationRegion (REGS, 0x8F, Zero, 0x50)
Field (REGS, ByteAcc, NoLock, Preserve)
{
    CLNT,   8,
    SA,     8,
    OFF,    8,
    VAL,    8,
    RWM,    8
}

Method (GET, 3, Serialized)
{
    If ((AVBE == One))
    {
        CLNT = Arg0
        SA = Arg1
        OFF = Arg2
        RWM = Zero
        If ((AVBG == One))
        {
            GPRW = Zero
        }
    }

    Return (VAL) /* \_SB_.PCI0.I2C7.PMI5.VAL_ */
}

Method (SET, 4, Serialized)
{
    If ((AVBE == One))
    {
        CLNT = Arg0
        SA = Arg1
        OFF = Arg2
        VAL = Arg3
        RWM = One
        If ((AVBG == One))
        {
            GPRW = One
        }
    }
}

Fixes: 0afa877a5650 ("ACPI / PMIC: intel: add REGS operation region support")
Signed-off-by: Hans de Goede &lt;hdegoede@redhat.com&gt;
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 009a789443fe4c8e6b1ecb7c16b4865c026184cd ]

The handling of PMIC register reads through writing 0 to address 4
of the OpRegion is wrong. Instead of returning the read value
through the value64, which is a no-op for function == ACPI_WRITE calls,
store the value and then on a subsequent function == ACPI_READ with
address == 3 (the address for the value field of the OpRegion)
return the stored value.

This has been tested on a Xiaomi Mi Pad 2 and makes the ACPI battery dev
there mostly functional (unfortunately there are still other issues).

Here are the SET() / GET() functions of the PMIC ACPI device,
which use this OpRegion, which clearly show the new behavior to
be correct:

OperationRegion (REGS, 0x8F, Zero, 0x50)
Field (REGS, ByteAcc, NoLock, Preserve)
{
    CLNT,   8,
    SA,     8,
    OFF,    8,
    VAL,    8,
    RWM,    8
}

Method (GET, 3, Serialized)
{
    If ((AVBE == One))
    {
        CLNT = Arg0
        SA = Arg1
        OFF = Arg2
        RWM = Zero
        If ((AVBG == One))
        {
            GPRW = Zero
        }
    }

    Return (VAL) /* \_SB_.PCI0.I2C7.PMI5.VAL_ */
}

Method (SET, 4, Serialized)
{
    If ((AVBE == One))
    {
        CLNT = Arg0
        SA = Arg1
        OFF = Arg2
        VAL = Arg3
        RWM = One
        If ((AVBG == One))
        {
            GPRW = One
        }
    }
}

Fixes: 0afa877a5650 ("ACPI / PMIC: intel: add REGS operation region support")
Signed-off-by: Hans de Goede &lt;hdegoede@redhat.com&gt;
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>ACPI: battery: Accept charges over the design capacity as full</title>
<updated>2021-11-26T10:48:30+00:00</updated>
<author>
<name>André Almeida</name>
<email>andrealmeid@collabora.com</email>
</author>
<published>2021-10-08T03:05:29+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=a1d2c265c64f5389d2dae764e7731ef5b576ac45'/>
<id>a1d2c265c64f5389d2dae764e7731ef5b576ac45</id>
<content type='text'>
[ Upstream commit 2835f327bd1240508db2c89fe94a056faa53c49a ]

Some buggy firmware and/or brand new batteries can support a charge that's
slightly over the reported design capacity. In such cases, the kernel will
report to userspace that the charging state of the battery is "Unknown",
when in reality the battery charge is "Full", at least from the design
capacity point of view. Make the fallback condition accepts capacities
over the designed capacity so userspace knows that is full.

Signed-off-by: André Almeida &lt;andrealmeid@collabora.com&gt;
Reviewed-by: Hans de Goede &lt;hdegoede@redhat.com&gt;
Reviewed-by: Sebastian Reichel &lt;sebastian.reichel@collabora.com&gt;
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 2835f327bd1240508db2c89fe94a056faa53c49a ]

Some buggy firmware and/or brand new batteries can support a charge that's
slightly over the reported design capacity. In such cases, the kernel will
report to userspace that the charging state of the battery is "Unknown",
when in reality the battery charge is "Full", at least from the design
capacity point of view. Make the fallback condition accepts capacities
over the designed capacity so userspace knows that is full.

Signed-off-by: André Almeida &lt;andrealmeid@collabora.com&gt;
Reviewed-by: Hans de Goede &lt;hdegoede@redhat.com&gt;
Reviewed-by: Sebastian Reichel &lt;sebastian.reichel@collabora.com&gt;
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>ACPICA: Avoid evaluating methods too early during system resume</title>
<updated>2021-11-26T10:48:29+00:00</updated>
<author>
<name>Rafael J. Wysocki</name>
<email>rafael.j.wysocki@intel.com</email>
</author>
<published>2021-09-29T16:31:25+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=95b622cdfeff5b6eb8ad25851357873051689842'/>
<id>95b622cdfeff5b6eb8ad25851357873051689842</id>
<content type='text'>
[ Upstream commit d3c4b6f64ad356c0d9ddbcf73fa471e6a841cc5c ]

ACPICA commit 0762982923f95eb652cf7ded27356b247c9774de

During wakeup from system-wide sleep states, acpi_get_sleep_type_data()
is called and it tries to get memory from the slab allocator in order
to evaluate a control method, but if KFENCE is enabled in the kernel,
the memory allocation attempt causes an IRQ work to be queued and a
self-IPI to be sent to the CPU running the code which requires the
memory controller to be ready, so if that happens too early in the
wakeup path, it doesn't work.

Prevent that from taking place by calling acpi_get_sleep_type_data()
for S0 upfront, when preparing to enter a given sleep state, and
saving the data obtained by it for later use during system wakeup.

BugLink: https://bugzilla.kernel.org/show_bug.cgi?id=214271
Reported-by: Reik Keutterling &lt;spielkind@gmail.com&gt;
Tested-by: Reik Keutterling &lt;spielkind@gmail.com&gt;
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit d3c4b6f64ad356c0d9ddbcf73fa471e6a841cc5c ]

ACPICA commit 0762982923f95eb652cf7ded27356b247c9774de

During wakeup from system-wide sleep states, acpi_get_sleep_type_data()
is called and it tries to get memory from the slab allocator in order
to evaluate a control method, but if KFENCE is enabled in the kernel,
the memory allocation attempt causes an IRQ work to be queued and a
self-IPI to be sent to the CPU running the code which requires the
memory controller to be ready, so if that happens too early in the
wakeup path, it doesn't work.

Prevent that from taking place by calling acpi_get_sleep_type_data()
for S0 upfront, when preparing to enter a given sleep state, and
saving the data obtained by it for later use during system wakeup.

BugLink: https://bugzilla.kernel.org/show_bug.cgi?id=214271
Reported-by: Reik Keutterling &lt;spielkind@gmail.com&gt;
Tested-by: Reik Keutterling &lt;spielkind@gmail.com&gt;
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>ACPI: NFIT: Fix support for virtual SPA ranges</title>
<updated>2021-08-26T12:37:22+00:00</updated>
<author>
<name>Dan Williams</name>
<email>dan.j.williams@intel.com</email>
</author>
<published>2021-08-11T18:53:37+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=b8f4f54609e2872f9c49356d7a4deae589f3840e'/>
<id>b8f4f54609e2872f9c49356d7a4deae589f3840e</id>
<content type='text'>
commit b93dfa6bda4d4e88e5386490f2b277a26958f9d3 upstream.

Fix the NFIT parsing code to treat a 0 index in a SPA Range Structure as
a special case and not match Region Mapping Structures that use 0 to
indicate that they are not mapped. Without this fix some platform BIOS
descriptions of "virtual disk" ranges do not result in the pmem driver
attaching to the range.

Details:
In addition to typical persistent memory ranges, the ACPI NFIT may also
convey "virtual" ranges. These ranges are indicated by a UUID in the SPA
Range Structure of UUID_VOLATILE_VIRTUAL_DISK, UUID_VOLATILE_VIRTUAL_CD,
UUID_PERSISTENT_VIRTUAL_DISK, or UUID_PERSISTENT_VIRTUAL_CD. The
critical difference between virtual ranges and UUID_PERSISTENT_MEMORY,
is that virtual do not support associations with Region Mapping
Structures.  For this reason the "index" value of virtual SPA Range
Structures is allowed to be 0. If a platform BIOS decides to represent
NVDIMMs with disconnected "Region Mapping Structures" (range-index ==
0), the kernel may falsely associate them with standalone ranges where
the "SPA Range Structure Index" is also zero. When this happens the
driver may falsely require labels where "virtual disks" are expected to
be label-less. I.e. "label-less" is where the namespace-range ==
region-range and the pmem driver attaches with no user action to create
a namespace.

Cc: Jacek Zloch &lt;jacek.zloch@intel.com&gt;
Cc: Lukasz Sobieraj &lt;lukasz.sobieraj@intel.com&gt;
Cc: "Lee, Chun-Yi" &lt;jlee@suse.com&gt;
Cc: &lt;stable@vger.kernel.org&gt;
Fixes: c2f32acdf848 ("acpi, nfit: treat virtual ramdisk SPA as pmem region")
Reported-by: Krzysztof Rusocki &lt;krzysztof.rusocki@intel.com&gt;
Reported-by: Damian Bassa &lt;damian.bassa@intel.com&gt;
Reviewed-by: Jeff Moyer &lt;jmoyer@redhat.com&gt;
Link: https://lore.kernel.org/r/162870796589.2521182.1240403310175570220.stgit@dwillia2-desk3.amr.corp.intel.com
Signed-off-by: Dan Williams &lt;dan.j.williams@intel.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit b93dfa6bda4d4e88e5386490f2b277a26958f9d3 upstream.

Fix the NFIT parsing code to treat a 0 index in a SPA Range Structure as
a special case and not match Region Mapping Structures that use 0 to
indicate that they are not mapped. Without this fix some platform BIOS
descriptions of "virtual disk" ranges do not result in the pmem driver
attaching to the range.

Details:
In addition to typical persistent memory ranges, the ACPI NFIT may also
convey "virtual" ranges. These ranges are indicated by a UUID in the SPA
Range Structure of UUID_VOLATILE_VIRTUAL_DISK, UUID_VOLATILE_VIRTUAL_CD,
UUID_PERSISTENT_VIRTUAL_DISK, or UUID_PERSISTENT_VIRTUAL_CD. The
critical difference between virtual ranges and UUID_PERSISTENT_MEMORY,
is that virtual do not support associations with Region Mapping
Structures.  For this reason the "index" value of virtual SPA Range
Structures is allowed to be 0. If a platform BIOS decides to represent
NVDIMMs with disconnected "Region Mapping Structures" (range-index ==
0), the kernel may falsely associate them with standalone ranges where
the "SPA Range Structure Index" is also zero. When this happens the
driver may falsely require labels where "virtual disks" are expected to
be label-less. I.e. "label-less" is where the namespace-range ==
region-range and the pmem driver attaches with no user action to create
a namespace.

Cc: Jacek Zloch &lt;jacek.zloch@intel.com&gt;
Cc: Lukasz Sobieraj &lt;lukasz.sobieraj@intel.com&gt;
Cc: "Lee, Chun-Yi" &lt;jlee@suse.com&gt;
Cc: &lt;stable@vger.kernel.org&gt;
Fixes: c2f32acdf848 ("acpi, nfit: treat virtual ramdisk SPA as pmem region")
Reported-by: Krzysztof Rusocki &lt;krzysztof.rusocki@intel.com&gt;
Reported-by: Damian Bassa &lt;damian.bassa@intel.com&gt;
Reviewed-by: Jeff Moyer &lt;jmoyer@redhat.com&gt;
Link: https://lore.kernel.org/r/162870796589.2521182.1240403310175570220.stgit@dwillia2-desk3.amr.corp.intel.com
Signed-off-by: Dan Williams &lt;dan.j.williams@intel.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>ACPI: AMBA: Fix resource name in /proc/iomem</title>
<updated>2021-07-20T14:21:14+00:00</updated>
<author>
<name>Liguang Zhang</name>
<email>zhangliguang@linux.alibaba.com</email>
</author>
<published>2021-06-29T11:27:48+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=f3a68bfc2db8948eff05620062a6b70e30532931'/>
<id>f3a68bfc2db8948eff05620062a6b70e30532931</id>
<content type='text'>
[ Upstream commit 7718629432676b5ebd9a32940782fe297a0abf8d ]

In function amba_handler_attach(), dev-&gt;res.name is initialized by
amba_device_alloc. But when address_found is false, dev-&gt;res.name is
assigned to null value, which leads to wrong resource name display in
/proc/iomem, "&lt;BAD&gt;" is seen for those resources.

Signed-off-by: Liguang Zhang &lt;zhangliguang@linux.alibaba.com&gt;
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 7718629432676b5ebd9a32940782fe297a0abf8d ]

In function amba_handler_attach(), dev-&gt;res.name is initialized by
amba_device_alloc. But when address_found is false, dev-&gt;res.name is
assigned to null value, which leads to wrong resource name display in
/proc/iomem, "&lt;BAD&gt;" is seen for those resources.

Signed-off-by: Liguang Zhang &lt;zhangliguang@linux.alibaba.com&gt;
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>ACPI: sysfs: Fix a buffer overrun problem with description_show()</title>
<updated>2021-07-20T14:21:01+00:00</updated>
<author>
<name>Krzysztof Wilczyński</name>
<email>kw@linux.com</email>
</author>
<published>2021-06-03T17:12:01+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=a4567b9318d8c510d9fef01f5f13db6d4083eb16'/>
<id>a4567b9318d8c510d9fef01f5f13db6d4083eb16</id>
<content type='text'>
[ Upstream commit 888be6067b97132c3992866bbcf647572253ab3f ]

Currently, a device description can be obtained using ACPI, if the _STR
method exists for a particular device, and then exposed to the userspace
via a sysfs object as a string value.

If the _STR method is available for a given device then the data
(usually a Unicode string) is read and stored in a buffer (of the
ACPI_TYPE_BUFFER type) with a pointer to said buffer cached in the
struct acpi_device_pnp for later access.

The description_show() function is responsible for exposing the device
description to the userspace via a corresponding sysfs object and
internally calls the utf16s_to_utf8s() function with a pointer to the
buffer that contains the Unicode string so that it can be converted from
UTF16 encoding to UTF8 and thus allowing for the value to be safely
stored and later displayed.

When invoking the utf16s_to_utf8s() function, the description_show()
function also sets a limit of the data that can be saved into a provided
buffer as a result of the character conversion to be a total of
PAGE_SIZE, and upon completion, the utf16s_to_utf8s() function returns
an integer value denoting the number of bytes that have been written
into the provided buffer.

Following the execution of the utf16s_to_utf8s() a newline character
will be added at the end of the resulting buffer so that when the value
is read in the userspace through the sysfs object then it would include
newline making it more accessible when working with the sysfs file
system in the shell, etc.  Normally, this wouldn't be a problem, but if
the function utf16s_to_utf8s() happens to return the number of bytes
written to be precisely PAGE_SIZE, then we would overrun the buffer and
write the newline character outside the allotted space which can have
undefined consequences or result in a failure.

To fix this buffer overrun, ensure that there always is enough space
left for the newline character to be safely appended.

Fixes: d1efe3c324ea ("ACPI: Add new sysfs interface to export device description")
Signed-off-by: Krzysztof Wilczyński &lt;kw@linux.com&gt;
Reviewed-by: Bjorn Helgaas &lt;bhelgaas@google.com&gt;
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 888be6067b97132c3992866bbcf647572253ab3f ]

Currently, a device description can be obtained using ACPI, if the _STR
method exists for a particular device, and then exposed to the userspace
via a sysfs object as a string value.

If the _STR method is available for a given device then the data
(usually a Unicode string) is read and stored in a buffer (of the
ACPI_TYPE_BUFFER type) with a pointer to said buffer cached in the
struct acpi_device_pnp for later access.

The description_show() function is responsible for exposing the device
description to the userspace via a corresponding sysfs object and
internally calls the utf16s_to_utf8s() function with a pointer to the
buffer that contains the Unicode string so that it can be converted from
UTF16 encoding to UTF8 and thus allowing for the value to be safely
stored and later displayed.

When invoking the utf16s_to_utf8s() function, the description_show()
function also sets a limit of the data that can be saved into a provided
buffer as a result of the character conversion to be a total of
PAGE_SIZE, and upon completion, the utf16s_to_utf8s() function returns
an integer value denoting the number of bytes that have been written
into the provided buffer.

Following the execution of the utf16s_to_utf8s() a newline character
will be added at the end of the resulting buffer so that when the value
is read in the userspace through the sysfs object then it would include
newline making it more accessible when working with the sysfs file
system in the shell, etc.  Normally, this wouldn't be a problem, but if
the function utf16s_to_utf8s() happens to return the number of bytes
written to be precisely PAGE_SIZE, then we would overrun the buffer and
write the newline character outside the allotted space which can have
undefined consequences or result in a failure.

To fix this buffer overrun, ensure that there always is enough space
left for the newline character to be safely appended.

Fixes: d1efe3c324ea ("ACPI: Add new sysfs interface to export device description")
Signed-off-by: Krzysztof Wilczyński &lt;kw@linux.com&gt;
Reviewed-by: Bjorn Helgaas &lt;bhelgaas@google.com&gt;
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>ACPI: tables: Add custom DSDT file as makefile prerequisite</title>
<updated>2021-07-20T14:21:00+00:00</updated>
<author>
<name>Richard Fitzgerald</name>
<email>rf@opensource.cirrus.com</email>
</author>
<published>2021-06-21T15:24:33+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=3d6591d03325973e48880484039c140758884c2a'/>
<id>3d6591d03325973e48880484039c140758884c2a</id>
<content type='text'>
[ Upstream commit d1059c1b1146870c52f3dac12cb7b6cbf39ed27f ]

A custom DSDT file is mostly used during development or debugging,
and in that case it is quite likely to want to rebuild the kernel
after changing ONLY the content of the DSDT.

This patch adds the custom DSDT as a prerequisite to tables.o
to ensure a rebuild if the DSDT file is updated. Make will merge
the prerequisites from multiple rules for the same target.

Signed-off-by: Richard Fitzgerald &lt;rf@opensource.cirrus.com&gt;
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit d1059c1b1146870c52f3dac12cb7b6cbf39ed27f ]

A custom DSDT file is mostly used during development or debugging,
and in that case it is quite likely to want to rebuild the kernel
after changing ONLY the content of the DSDT.

This patch adds the custom DSDT as a prerequisite to tables.o
to ensure a rebuild if the DSDT file is updated. Make will merge
the prerequisites from multiple rules for the same target.

Signed-off-by: Richard Fitzgerald &lt;rf@opensource.cirrus.com&gt;
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>ACPI: bus: Call kobject_put() in acpi_init() error path</title>
<updated>2021-07-20T14:21:00+00:00</updated>
<author>
<name>Hanjun Guo</name>
<email>guohanjun@huawei.com</email>
</author>
<published>2021-06-02T09:36:50+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=2c62eaa6591b66c46b0d1eaecacfe0c463463bed'/>
<id>2c62eaa6591b66c46b0d1eaecacfe0c463463bed</id>
<content type='text'>
[ Upstream commit 4ac7a817f1992103d4e68e9837304f860b5e7300 ]

Although the system will not be in a good condition or it will not
boot if acpi_bus_init() fails, it is still necessary to put the
kobject in the error path before returning to avoid leaking memory.

Signed-off-by: Hanjun Guo &lt;guohanjun@huawei.com&gt;
[ rjw: Subject and changelog edits ]
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 4ac7a817f1992103d4e68e9837304f860b5e7300 ]

Although the system will not be in a good condition or it will not
boot if acpi_bus_init() fails, it is still necessary to put the
kobject in the error path before returning to avoid leaking memory.

Signed-off-by: Hanjun Guo &lt;guohanjun@huawei.com&gt;
[ rjw: Subject and changelog edits ]
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
</feed>
