<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux-stable.git/drivers/firmware, branch v4.9.183</title>
<subtitle>Linux kernel stable tree</subtitle>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/'/>
<entry>
<title>efi/libstub: Unify command line param parsing</title>
<updated>2019-06-11T10:22:45+00:00</updated>
<author>
<name>Ard Biesheuvel</name>
<email>ard.biesheuvel@linaro.org</email>
</author>
<published>2017-04-04T16:09:08+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=8fca3c3646831e9fe9da08d8c9234a04b6848e06'/>
<id>8fca3c3646831e9fe9da08d8c9234a04b6848e06</id>
<content type='text'>
commit 60f38de7a8d4e816100ceafd1b382df52527bd50 upstream.

Merge the parsing of the command line carried out in arm-stub.c with
the handling in efi_parse_options(). Note that this also fixes the
missing handling of CONFIG_CMDLINE_FORCE=y, in which case the builtin
command line should supersede the one passed by the firmware.

Signed-off-by: Ard Biesheuvel &lt;ard.biesheuvel@linaro.org&gt;
Cc: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Cc: Matt Fleming &lt;matt@codeblueprint.co.uk&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Cc: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Cc: bhe@redhat.com
Cc: bhsharma@redhat.com
Cc: bp@alien8.de
Cc: eugene@hp.com
Cc: evgeny.kalugin@intel.com
Cc: jhugo@codeaurora.org
Cc: leif.lindholm@linaro.org
Cc: linux-efi@vger.kernel.org
Cc: mark.rutland@arm.com
Cc: roy.franz@cavium.com
Cc: rruigrok@codeaurora.org
Link: http://lkml.kernel.org/r/20170404160910.28115-1-ard.biesheuvel@linaro.org
Signed-off-by: Ingo Molnar &lt;mingo@kernel.org&gt;
[ardb: fix up merge conflicts with 4.9.180]
Signed-off-by: Ard Biesheuvel &lt;ard.biesheuvel@linaro.org&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 60f38de7a8d4e816100ceafd1b382df52527bd50 upstream.

Merge the parsing of the command line carried out in arm-stub.c with
the handling in efi_parse_options(). Note that this also fixes the
missing handling of CONFIG_CMDLINE_FORCE=y, in which case the builtin
command line should supersede the one passed by the firmware.

Signed-off-by: Ard Biesheuvel &lt;ard.biesheuvel@linaro.org&gt;
Cc: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Cc: Matt Fleming &lt;matt@codeblueprint.co.uk&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Cc: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Cc: bhe@redhat.com
Cc: bhsharma@redhat.com
Cc: bp@alien8.de
Cc: eugene@hp.com
Cc: evgeny.kalugin@intel.com
Cc: jhugo@codeaurora.org
Cc: leif.lindholm@linaro.org
Cc: linux-efi@vger.kernel.org
Cc: mark.rutland@arm.com
Cc: roy.franz@cavium.com
Cc: rruigrok@codeaurora.org
Link: http://lkml.kernel.org/r/20170404160910.28115-1-ard.biesheuvel@linaro.org
Signed-off-by: Ingo Molnar &lt;mingo@kernel.org&gt;
[ardb: fix up merge conflicts with 4.9.180]
Signed-off-by: Ard Biesheuvel &lt;ard.biesheuvel@linaro.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>efi/memattr: Don't bail on zero VA if it equals the region's PA</title>
<updated>2019-04-05T20:29:12+00:00</updated>
<author>
<name>Ard Biesheuvel</name>
<email>ard.biesheuvel@linaro.org</email>
</author>
<published>2019-02-02T09:41:12+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=17dc1d957d83fcd8870659a9fdf315d1756ab640'/>
<id>17dc1d957d83fcd8870659a9fdf315d1756ab640</id>
<content type='text'>
[ Upstream commit 5de0fef0230f3c8d75cff450a71740a7bf2db866 ]

The EFI memory attributes code cross-references the EFI memory map with
the more granular EFI memory attributes table to ensure that they are in
sync before applying the strict permissions to the regions it describes.

Since we always install virtual mappings for the EFI runtime regions to
which these strict permissions apply, we currently perform a sanity check
on the EFI memory descriptor, and ensure that the EFI_MEMORY_RUNTIME bit
is set, and that the virtual address has been assigned.

However, in cases where a runtime region exists at physical address 0x0,
and the virtual mapping equals the physical mapping, e.g., when running
in mixed mode on x86, we encounter a memory descriptor with the runtime
attribute and virtual address 0x0, and incorrectly draw the conclusion
that a runtime region exists for which no virtual mapping was installed,
and give up altogether. The consequence of this is that firmware mappings
retain their read-write-execute permissions, making the system more
vulnerable to attacks.

So let's only bail if the virtual address of 0x0 has been assigned to a
physical region that does not reside at address 0x0.

Signed-off-by: Ard Biesheuvel &lt;ard.biesheuvel@linaro.org&gt;
Acked-by: Sai Praneeth Prakhya &lt;sai.praneeth.prakhya@intel.com&gt;
Cc: AKASHI Takahiro &lt;takahiro.akashi@linaro.org&gt;
Cc: Alexander Graf &lt;agraf@suse.de&gt;
Cc: Bjorn Andersson &lt;bjorn.andersson@linaro.org&gt;
Cc: Borislav Petkov &lt;bp@alien8.de&gt;
Cc: Heinrich Schuchardt &lt;xypron.glpk@gmx.de&gt;
Cc: Jeffrey Hugo &lt;jhugo@codeaurora.org&gt;
Cc: Lee Jones &lt;lee.jones@linaro.org&gt;
Cc: Leif Lindholm &lt;leif.lindholm@linaro.org&gt;
Cc: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Cc: Matt Fleming &lt;matt@codeblueprint.co.uk&gt;
Cc: Peter Jones &lt;pjones@redhat.com&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Cc: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Cc: linux-efi@vger.kernel.org
Fixes: 10f0d2f577053 ("efi: Implement generic support for the Memory ...")
Link: http://lkml.kernel.org/r/20190202094119.13230-4-ard.biesheuvel@linaro.org
Signed-off-by: Ingo Molnar &lt;mingo@kernel.org&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 5de0fef0230f3c8d75cff450a71740a7bf2db866 ]

The EFI memory attributes code cross-references the EFI memory map with
the more granular EFI memory attributes table to ensure that they are in
sync before applying the strict permissions to the regions it describes.

Since we always install virtual mappings for the EFI runtime regions to
which these strict permissions apply, we currently perform a sanity check
on the EFI memory descriptor, and ensure that the EFI_MEMORY_RUNTIME bit
is set, and that the virtual address has been assigned.

However, in cases where a runtime region exists at physical address 0x0,
and the virtual mapping equals the physical mapping, e.g., when running
in mixed mode on x86, we encounter a memory descriptor with the runtime
attribute and virtual address 0x0, and incorrectly draw the conclusion
that a runtime region exists for which no virtual mapping was installed,
and give up altogether. The consequence of this is that firmware mappings
retain their read-write-execute permissions, making the system more
vulnerable to attacks.

So let's only bail if the virtual address of 0x0 has been assigned to a
physical region that does not reside at address 0x0.

Signed-off-by: Ard Biesheuvel &lt;ard.biesheuvel@linaro.org&gt;
Acked-by: Sai Praneeth Prakhya &lt;sai.praneeth.prakhya@intel.com&gt;
Cc: AKASHI Takahiro &lt;takahiro.akashi@linaro.org&gt;
Cc: Alexander Graf &lt;agraf@suse.de&gt;
Cc: Bjorn Andersson &lt;bjorn.andersson@linaro.org&gt;
Cc: Borislav Petkov &lt;bp@alien8.de&gt;
Cc: Heinrich Schuchardt &lt;xypron.glpk@gmx.de&gt;
Cc: Jeffrey Hugo &lt;jhugo@codeaurora.org&gt;
Cc: Lee Jones &lt;lee.jones@linaro.org&gt;
Cc: Leif Lindholm &lt;leif.lindholm@linaro.org&gt;
Cc: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Cc: Matt Fleming &lt;matt@codeblueprint.co.uk&gt;
Cc: Peter Jones &lt;pjones@redhat.com&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Cc: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Cc: linux-efi@vger.kernel.org
Fixes: 10f0d2f577053 ("efi: Implement generic support for the Memory ...")
Link: http://lkml.kernel.org/r/20190202094119.13230-4-ard.biesheuvel@linaro.org
Signed-off-by: Ingo Molnar &lt;mingo@kernel.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>iscsi_ibft: Fix missing break in switch statement</title>
<updated>2019-03-13T21:05:01+00:00</updated>
<author>
<name>Gustavo A. R. Silva</name>
<email>gustavo@embeddedor.com</email>
</author>
<published>2019-02-11T18:43:23+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=6263e82643db9ba45ce66642401928a0a175a399'/>
<id>6263e82643db9ba45ce66642401928a0a175a399</id>
<content type='text'>
commit df997abeebadaa4824271009e2d2b526a70a11cb upstream.

Add missing break statement in order to prevent the code from falling
through to case ISCSI_BOOT_TGT_NAME, which is unnecessary.

This bug was found thanks to the ongoing efforts to enable
-Wimplicit-fallthrough.

Fixes: b33a84a38477 ("ibft: convert iscsi_ibft module to iscsi boot lib")
Cc: stable@vger.kernel.org
Signed-off-by: Gustavo A. R. Silva &lt;gustavo@embeddedor.com&gt;
Signed-off-by: Konrad Rzeszutek Wilk &lt;konrad.wilk@oracle.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 df997abeebadaa4824271009e2d2b526a70a11cb upstream.

Add missing break statement in order to prevent the code from falling
through to case ISCSI_BOOT_TGT_NAME, which is unnecessary.

This bug was found thanks to the ongoing efforts to enable
-Wimplicit-fallthrough.

Fixes: b33a84a38477 ("ibft: convert iscsi_ibft module to iscsi boot lib")
Cc: stable@vger.kernel.org
Signed-off-by: Gustavo A. R. Silva &lt;gustavo@embeddedor.com&gt;
Signed-off-by: Konrad Rzeszutek Wilk &lt;konrad.wilk@oracle.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>x86/platform/UV: Use efi_runtime_lock to serialise BIOS calls</title>
<updated>2019-02-20T09:18:33+00:00</updated>
<author>
<name>Hedi Berriche</name>
<email>hedi.berriche@hpe.com</email>
</author>
<published>2019-02-13T19:34:13+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=967859281fd18e54ff233393cdc15616d00a3453'/>
<id>967859281fd18e54ff233393cdc15616d00a3453</id>
<content type='text'>
commit f331e766c4be33f4338574f3c9f7f77e98ab4571 upstream.

Calls into UV firmware must be protected against concurrency, expose the
efi_runtime_lock to the UV platform, and use it to serialise UV BIOS
calls.

Signed-off-by: Hedi Berriche &lt;hedi.berriche@hpe.com&gt;
Signed-off-by: Borislav Petkov &lt;bp@suse.de&gt;
Reviewed-by: Ard Biesheuvel &lt;ard.biesheuvel@linaro.org&gt;
Reviewed-by: Russ Anderson &lt;rja@hpe.com&gt;
Reviewed-by: Dimitri Sivanich &lt;sivanich@hpe.com&gt;
Reviewed-by: Mike Travis &lt;mike.travis@hpe.com&gt;
Cc: Andy Shevchenko &lt;andy@infradead.org&gt;
Cc: Bhupesh Sharma &lt;bhsharma@redhat.com&gt;
Cc: Darren Hart &lt;dvhart@infradead.org&gt;
Cc: "H. Peter Anvin" &lt;hpa@zytor.com&gt;
Cc: Ingo Molnar &lt;mingo@redhat.com&gt;
Cc: linux-efi &lt;linux-efi@vger.kernel.org&gt;
Cc: platform-driver-x86@vger.kernel.org
Cc: stable@vger.kernel.org # v4.9+
Cc: Steve Wahl &lt;steve.wahl@hpe.com&gt;
Cc: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Cc: x86-ml &lt;x86@kernel.org&gt;
Link: https://lkml.kernel.org/r/20190213193413.25560-5-hedi.berriche@hpe.com
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 f331e766c4be33f4338574f3c9f7f77e98ab4571 upstream.

Calls into UV firmware must be protected against concurrency, expose the
efi_runtime_lock to the UV platform, and use it to serialise UV BIOS
calls.

Signed-off-by: Hedi Berriche &lt;hedi.berriche@hpe.com&gt;
Signed-off-by: Borislav Petkov &lt;bp@suse.de&gt;
Reviewed-by: Ard Biesheuvel &lt;ard.biesheuvel@linaro.org&gt;
Reviewed-by: Russ Anderson &lt;rja@hpe.com&gt;
Reviewed-by: Dimitri Sivanich &lt;sivanich@hpe.com&gt;
Reviewed-by: Mike Travis &lt;mike.travis@hpe.com&gt;
Cc: Andy Shevchenko &lt;andy@infradead.org&gt;
Cc: Bhupesh Sharma &lt;bhsharma@redhat.com&gt;
Cc: Darren Hart &lt;dvhart@infradead.org&gt;
Cc: "H. Peter Anvin" &lt;hpa@zytor.com&gt;
Cc: Ingo Molnar &lt;mingo@redhat.com&gt;
Cc: linux-efi &lt;linux-efi@vger.kernel.org&gt;
Cc: platform-driver-x86@vger.kernel.org
Cc: stable@vger.kernel.org # v4.9+
Cc: Steve Wahl &lt;steve.wahl@hpe.com&gt;
Cc: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Cc: x86-ml &lt;x86@kernel.org&gt;
Link: https://lkml.kernel.org/r/20190213193413.25560-5-hedi.berriche@hpe.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>firmware/efi: Add NULL pointer checks in efivars API functions</title>
<updated>2019-02-12T18:44:53+00:00</updated>
<author>
<name>Arend van Spriel</name>
<email>arend.vanspriel@broadcom.com</email>
</author>
<published>2018-11-29T17:12:27+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=1773543ea9bac92670a2e84ced14839c8f8a8399'/>
<id>1773543ea9bac92670a2e84ced14839c8f8a8399</id>
<content type='text'>
[ Upstream commit ab2180a15ce54739fed381efb4cb12e78dfb1561 ]

Since commit:

   ce2e6db554fa ("brcmfmac: Add support for getting nvram contents from EFI variables")

we have a device driver accessing the efivars API. Several functions in
the efivars API assume __efivars is set, i.e., that they will be accessed
only after efivars_register() has been called. However, the following NULL
pointer access was reported calling efivar_entry_size() from the brcmfmac
device driver:

  Unable to handle kernel NULL pointer dereference at virtual address 00000008
  pgd = 60bfa5f1
  [00000008] *pgd=00000000
  Internal error: Oops: 5 [#1] SMP ARM
  ...
  Hardware name: NVIDIA Tegra SoC (Flattened Device Tree)
  Workqueue: events request_firmware_work_func
  PC is at efivar_entry_size+0x28/0x90
  LR is at brcmf_fw_complete_request+0x3f8/0x8d4 [brcmfmac]
  pc : [&lt;c0c40718&gt;]    lr : [&lt;bf2a3ef4&gt;]    psr: a00d0113
  sp : ede7fe28  ip : ee983410  fp : c1787f30
  r10: 00000000  r9 : 00000000  r8 : bf2b2258
  r7 : ee983000  r6 : c1604c48  r5 : ede7fe88  r4 : edf337c0
  r3 : 00000000  r2 : 00000000  r1 : ede7fe88  r0 : c17712c8
  Flags: NzCv  IRQs on  FIQs on  Mode SVC_32  ISA ARM  Segment none
  Control: 10c5387d  Table: ad16804a  DAC: 00000051

Disassembly showed that the local static variable __efivars is NULL,
which is not entirely unexpected given that it is a non-EFI platform.

So add a NULL pointer check to efivar_entry_size(), and to related
functions while at it. In efivars_register() a couple of sanity checks
are added as well.

Reported-by: Jon Hunter &lt;jonathanh@nvidia.com&gt;
Signed-off-by: Arend van Spriel &lt;arend.vanspriel@broadcom.com&gt;
Signed-off-by: Ard Biesheuvel &lt;ard.biesheuvel@linaro.org&gt;
Cc: Andy Lutomirski &lt;luto@kernel.org&gt;
Cc: Bhupesh Sharma &lt;bhsharma@redhat.com&gt;
Cc: Borislav Petkov &lt;bp@alien8.de&gt;
Cc: Dave Hansen &lt;dave.hansen@intel.com&gt;
Cc: Eric Snowberg &lt;eric.snowberg@oracle.com&gt;
Cc: Hans de Goede &lt;hdegoede@redhat.com&gt;
Cc: Joe Perches &lt;joe@perches.com&gt;
Cc: Julien Thierry &lt;julien.thierry@arm.com&gt;
Cc: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Cc: Marc Zyngier &lt;marc.zyngier@arm.com&gt;
Cc: Matt Fleming &lt;matt@codeblueprint.co.uk&gt;
Cc: Nathan Chancellor &lt;natechancellor@gmail.com&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Cc: Sai Praneeth Prakhya &lt;sai.praneeth.prakhya@intel.com&gt;
Cc: Sedat Dilek &lt;sedat.dilek@gmail.com&gt;
Cc: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Cc: YiFei Zhu &lt;zhuyifei1999@gmail.com&gt;
Cc: linux-efi@vger.kernel.org
Link: http://lkml.kernel.org/r/20181129171230.18699-9-ard.biesheuvel@linaro.org
Signed-off-by: Ingo Molnar &lt;mingo@kernel.org&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 ab2180a15ce54739fed381efb4cb12e78dfb1561 ]

Since commit:

   ce2e6db554fa ("brcmfmac: Add support for getting nvram contents from EFI variables")

we have a device driver accessing the efivars API. Several functions in
the efivars API assume __efivars is set, i.e., that they will be accessed
only after efivars_register() has been called. However, the following NULL
pointer access was reported calling efivar_entry_size() from the brcmfmac
device driver:

  Unable to handle kernel NULL pointer dereference at virtual address 00000008
  pgd = 60bfa5f1
  [00000008] *pgd=00000000
  Internal error: Oops: 5 [#1] SMP ARM
  ...
  Hardware name: NVIDIA Tegra SoC (Flattened Device Tree)
  Workqueue: events request_firmware_work_func
  PC is at efivar_entry_size+0x28/0x90
  LR is at brcmf_fw_complete_request+0x3f8/0x8d4 [brcmfmac]
  pc : [&lt;c0c40718&gt;]    lr : [&lt;bf2a3ef4&gt;]    psr: a00d0113
  sp : ede7fe28  ip : ee983410  fp : c1787f30
  r10: 00000000  r9 : 00000000  r8 : bf2b2258
  r7 : ee983000  r6 : c1604c48  r5 : ede7fe88  r4 : edf337c0
  r3 : 00000000  r2 : 00000000  r1 : ede7fe88  r0 : c17712c8
  Flags: NzCv  IRQs on  FIQs on  Mode SVC_32  ISA ARM  Segment none
  Control: 10c5387d  Table: ad16804a  DAC: 00000051

Disassembly showed that the local static variable __efivars is NULL,
which is not entirely unexpected given that it is a non-EFI platform.

So add a NULL pointer check to efivar_entry_size(), and to related
functions while at it. In efivars_register() a couple of sanity checks
are added as well.

Reported-by: Jon Hunter &lt;jonathanh@nvidia.com&gt;
Signed-off-by: Arend van Spriel &lt;arend.vanspriel@broadcom.com&gt;
Signed-off-by: Ard Biesheuvel &lt;ard.biesheuvel@linaro.org&gt;
Cc: Andy Lutomirski &lt;luto@kernel.org&gt;
Cc: Bhupesh Sharma &lt;bhsharma@redhat.com&gt;
Cc: Borislav Petkov &lt;bp@alien8.de&gt;
Cc: Dave Hansen &lt;dave.hansen@intel.com&gt;
Cc: Eric Snowberg &lt;eric.snowberg@oracle.com&gt;
Cc: Hans de Goede &lt;hdegoede@redhat.com&gt;
Cc: Joe Perches &lt;joe@perches.com&gt;
Cc: Julien Thierry &lt;julien.thierry@arm.com&gt;
Cc: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Cc: Marc Zyngier &lt;marc.zyngier@arm.com&gt;
Cc: Matt Fleming &lt;matt@codeblueprint.co.uk&gt;
Cc: Nathan Chancellor &lt;natechancellor@gmail.com&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Cc: Sai Praneeth Prakhya &lt;sai.praneeth.prakhya@intel.com&gt;
Cc: Sedat Dilek &lt;sedat.dilek@gmail.com&gt;
Cc: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Cc: YiFei Zhu &lt;zhuyifei1999@gmail.com&gt;
Cc: linux-efi@vger.kernel.org
Link: http://lkml.kernel.org/r/20181129171230.18699-9-ard.biesheuvel@linaro.org
Signed-off-by: Ingo Molnar &lt;mingo@kernel.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>efi/libstub: Make file I/O chunking x86-specific</title>
<updated>2018-12-05T18:42:42+00:00</updated>
<author>
<name>Ard Biesheuvel</name>
<email>ard.biesheuvel@linaro.org</email>
</author>
<published>2017-02-06T11:22:46+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=6d075d215b5b8875fba153670e19560a2ffcdd45'/>
<id>6d075d215b5b8875fba153670e19560a2ffcdd45</id>
<content type='text'>
(commit b3879a4d3a31ef14265a52e8d941cf4b0f6627ae upstream)

The ARM decompressor is finicky when it comes to uninitialized variables
with local linkage, the reason being that it may relocate .text and .bss
independently when executing from ROM. This is only possible if all
references into .bss from .text are absolute, and this happens to be the
case for references emitted under -fpic to symbols with external linkage,
and so all .bss references must involve symbols with external linkage.

When building the ARM stub using clang, the initialized local variable
__chunk_size is optimized into a zero-initialized flag that indicates
whether chunking is in effect or not. This flag is therefore emitted into
.bss, which triggers the ARM decompressor's diagnostics, resulting in a
failed build.

Under UEFI, we never execute the decompressor from ROM, so the diagnostic
makes little sense here. But we can easily work around the issue by making
__chunk_size global instead.

However, given that the file I/O chunking that is controlled by the
__chunk_size variable is intended to work around known bugs on various
x86 implementations of UEFI, we can simply make the chunking an x86
specific feature. This is an improvement by itself, and also removes the
need to parse the efi= options in the stub entirely.

Tested-by: Arnd Bergmann &lt;arnd@arndb.de&gt;
Signed-off-by: Ard Biesheuvel &lt;ard.biesheuvel@linaro.org&gt;
Reviewed-by: Matt Fleming &lt;matt@codeblueprint.co.uk&gt;
Cc: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Cc: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Cc: linux-efi@vger.kernel.org
Link: http://lkml.kernel.org/r/1486380166-31868-8-git-send-email-ard.biesheuvel@linaro.org
[ Small readability edits. ]
Signed-off-by: Ingo Molnar &lt;mingo@kernel.org&gt;
Signed-off-by: Nick Desaulniers &lt;ndesaulniers@google.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 b3879a4d3a31ef14265a52e8d941cf4b0f6627ae upstream)

The ARM decompressor is finicky when it comes to uninitialized variables
with local linkage, the reason being that it may relocate .text and .bss
independently when executing from ROM. This is only possible if all
references into .bss from .text are absolute, and this happens to be the
case for references emitted under -fpic to symbols with external linkage,
and so all .bss references must involve symbols with external linkage.

When building the ARM stub using clang, the initialized local variable
__chunk_size is optimized into a zero-initialized flag that indicates
whether chunking is in effect or not. This flag is therefore emitted into
.bss, which triggers the ARM decompressor's diagnostics, resulting in a
failed build.

Under UEFI, we never execute the decompressor from ROM, so the diagnostic
makes little sense here. But we can easily work around the issue by making
__chunk_size global instead.

However, given that the file I/O chunking that is controlled by the
__chunk_size variable is intended to work around known bugs on various
x86 implementations of UEFI, we can simply make the chunking an x86
specific feature. This is an improvement by itself, and also removes the
need to parse the efi= options in the stub entirely.

Tested-by: Arnd Bergmann &lt;arnd@arndb.de&gt;
Signed-off-by: Ard Biesheuvel &lt;ard.biesheuvel@linaro.org&gt;
Reviewed-by: Matt Fleming &lt;matt@codeblueprint.co.uk&gt;
Cc: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Cc: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Cc: linux-efi@vger.kernel.org
Link: http://lkml.kernel.org/r/1486380166-31868-8-git-send-email-ard.biesheuvel@linaro.org
[ Small readability edits. ]
Signed-off-by: Ingo Molnar &lt;mingo@kernel.org&gt;
Signed-off-by: Nick Desaulniers &lt;ndesaulniers@google.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>efi/libstub: arm: support building with clang</title>
<updated>2018-12-05T18:42:41+00:00</updated>
<author>
<name>Alistair Strachan</name>
<email>astrachan@google.com</email>
</author>
<published>2018-12-03T19:40:57+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=fb660794cd6179fa1b2d6890afb99c93d99ee2c8'/>
<id>fb660794cd6179fa1b2d6890afb99c93d99ee2c8</id>
<content type='text'>
(commit 41f1c48420709470c51ee0e54b6fb28b956bb4e0 upstream)

When building with CONFIG_EFI and CONFIG_EFI_STUB on ARM, the libstub
Makefile would use -mno-single-pic-base without checking it was
supported by the compiler. As the ARM (32-bit) clang backend does not
support this flag, the build would fail.

This changes the Makefile to check the compiler's support for
-mno-single-pic-base before using it, similar to c1c386681bd7 ("ARM:
8767/1: add support for building ARM kernel with clang").

Signed-off-by: Alistair Strachan &lt;astrachan@google.com&gt;
Reviewed-by: Stefan Agner &lt;stefan@agner.ch&gt;
Signed-off-by: Ard Biesheuvel &lt;ard.biesheuvel@linaro.org&gt;
[ND: adjusted due to missing commit ce279d374ff3 ("efi/libstub:
 Only disable stackleak plugin for arm64")]
Signed-off-by: Nick Desaulniers &lt;ndesaulniers@google.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 41f1c48420709470c51ee0e54b6fb28b956bb4e0 upstream)

When building with CONFIG_EFI and CONFIG_EFI_STUB on ARM, the libstub
Makefile would use -mno-single-pic-base without checking it was
supported by the compiler. As the ARM (32-bit) clang backend does not
support this flag, the build would fail.

This changes the Makefile to check the compiler's support for
-mno-single-pic-base before using it, similar to c1c386681bd7 ("ARM:
8767/1: add support for building ARM kernel with clang").

Signed-off-by: Alistair Strachan &lt;astrachan@google.com&gt;
Reviewed-by: Stefan Agner &lt;stefan@agner.ch&gt;
Signed-off-by: Ard Biesheuvel &lt;ard.biesheuvel@linaro.org&gt;
[ND: adjusted due to missing commit ce279d374ff3 ("efi/libstub:
 Only disable stackleak plugin for arm64")]
Signed-off-by: Nick Desaulniers &lt;ndesaulniers@google.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>efi/arm: Revert deferred unmap of early memmap mapping</title>
<updated>2018-12-01T08:44:21+00:00</updated>
<author>
<name>Ard Biesheuvel</name>
<email>ard.biesheuvel@linaro.org</email>
</author>
<published>2018-11-14T17:55:41+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=b57951ed2b6d5a064be3956dbc0c0271ca13657a'/>
<id>b57951ed2b6d5a064be3956dbc0c0271ca13657a</id>
<content type='text'>
[ Upstream commit 33412b8673135b18ea42beb7f5117ed0091798b6 ]

Commit:

  3ea86495aef2 ("efi/arm: preserve early mapping of UEFI memory map longer for BGRT")

deferred the unmap of the early mapping of the UEFI memory map to
accommodate the ACPI BGRT code, which looks up the memory type that
backs the BGRT table to validate it against the requirements of the UEFI spec.

Unfortunately, this causes problems on ARM, which does not permit
early mappings to persist after paging_init() is called, resulting
in a WARN() splat. Since we don't support the BGRT table on ARM anway,
let's revert ARM to the old behaviour, which is to take down the
early mapping at the end of efi_init().

Signed-off-by: Ard Biesheuvel &lt;ard.biesheuvel@linaro.org&gt;
Cc: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Cc: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Cc: linux-efi@vger.kernel.org
Fixes: 3ea86495aef2 ("efi/arm: preserve early mapping of UEFI memory ...")
Link: http://lkml.kernel.org/r/20181114175544.12860-3-ard.biesheuvel@linaro.org
Signed-off-by: Ingo Molnar &lt;mingo@kernel.org&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 33412b8673135b18ea42beb7f5117ed0091798b6 ]

Commit:

  3ea86495aef2 ("efi/arm: preserve early mapping of UEFI memory map longer for BGRT")

deferred the unmap of the early mapping of the UEFI memory map to
accommodate the ACPI BGRT code, which looks up the memory type that
backs the BGRT table to validate it against the requirements of the UEFI spec.

Unfortunately, this causes problems on ARM, which does not permit
early mappings to persist after paging_init() is called, resulting
in a WARN() splat. Since we don't support the BGRT table on ARM anway,
let's revert ARM to the old behaviour, which is to take down the
early mapping at the end of efi_init().

Signed-off-by: Ard Biesheuvel &lt;ard.biesheuvel@linaro.org&gt;
Cc: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Cc: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Cc: linux-efi@vger.kernel.org
Fixes: 3ea86495aef2 ("efi/arm: preserve early mapping of UEFI memory ...")
Link: http://lkml.kernel.org/r/20181114175544.12860-3-ard.biesheuvel@linaro.org
Signed-off-by: Ingo Molnar &lt;mingo@kernel.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>efi/libstub/arm64: Set -fpie when building the EFI stub</title>
<updated>2018-11-23T07:20:36+00:00</updated>
<author>
<name>Ard Biesheuvel</name>
<email>ard.biesheuvel@linaro.org</email>
</author>
<published>2017-08-18T19:49:37+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=27b5ebf61818749b3568354c64a8ec2d9cd5ecca'/>
<id>27b5ebf61818749b3568354c64a8ec2d9cd5ecca</id>
<content type='text'>
commit 91ee5b21ee026c49e4e7483de69b55b8b47042be upstream.

Clang may emit absolute symbol references when building in non-PIC mode,
even when using the default 'small' code model, which is already mostly
position independent to begin with, due to its use of adrp/add pairs
that have a relative range of +/- 4 GB. The remedy is to pass the -fpie
flag, which can be done safely now that the code has been updated to avoid
GOT indirections (which may be emitted due to the compiler assuming that
the PIC/PIE code may end up in a shared library that is subject to ELF
symbol preemption)

Passing -fpie when building code that needs to execute at an a priori
unknown offset is arguably an improvement in any case, and given that
the recent visibility changes allow the PIC build to pass with GCC as
well, let's add -fpie for all arm64 builds rather than only for Clang.

Tested-by: Matthias Kaehlcke &lt;mka@chromium.org&gt;
Signed-off-by: Ard Biesheuvel &lt;ard.biesheuvel@linaro.org&gt;
Cc: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Cc: Matt Fleming &lt;matt@codeblueprint.co.uk&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Cc: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Cc: linux-efi@vger.kernel.org
Link: http://lkml.kernel.org/r/20170818194947.19347-5-ard.biesheuvel@linaro.org
Signed-off-by: Ingo Molnar &lt;mingo@kernel.org&gt;
Signed-off-by: Nick Desaulniers &lt;ndesaulniers@google.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 91ee5b21ee026c49e4e7483de69b55b8b47042be upstream.

Clang may emit absolute symbol references when building in non-PIC mode,
even when using the default 'small' code model, which is already mostly
position independent to begin with, due to its use of adrp/add pairs
that have a relative range of +/- 4 GB. The remedy is to pass the -fpie
flag, which can be done safely now that the code has been updated to avoid
GOT indirections (which may be emitted due to the compiler assuming that
the PIC/PIE code may end up in a shared library that is subject to ELF
symbol preemption)

Passing -fpie when building code that needs to execute at an a priori
unknown offset is arguably an improvement in any case, and given that
the recent visibility changes allow the PIC build to pass with GCC as
well, let's add -fpie for all arm64 builds rather than only for Clang.

Tested-by: Matthias Kaehlcke &lt;mka@chromium.org&gt;
Signed-off-by: Ard Biesheuvel &lt;ard.biesheuvel@linaro.org&gt;
Cc: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Cc: Matt Fleming &lt;matt@codeblueprint.co.uk&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Cc: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Cc: linux-efi@vger.kernel.org
Link: http://lkml.kernel.org/r/20170818194947.19347-5-ard.biesheuvel@linaro.org
Signed-off-by: Ingo Molnar &lt;mingo@kernel.org&gt;
Signed-off-by: Nick Desaulniers &lt;ndesaulniers@google.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>efi/libstub: Preserve .debug sections after absolute relocation check</title>
<updated>2018-11-23T07:20:36+00:00</updated>
<author>
<name>Ard Biesheuvel</name>
<email>ard.biesheuvel@linaro.org</email>
</author>
<published>2017-01-31T13:21:42+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=6b66b2d89e8dde45e92337f7e48e1677748a8c50'/>
<id>6b66b2d89e8dde45e92337f7e48e1677748a8c50</id>
<content type='text'>
commit 696204faa6e8a318320ebb49d9fa69bc8275644d upstream.

The build commands for the ARM and arm64 EFI stubs strip the .debug
sections and other sections that may legally contain absolute relocations,
in order to inspect the remaining sections for the presence of such
relocations.

This leaves us without debugging symbols in the stub for no good reason,
considering that these sections are omitted from the kernel binary anyway,
and that these relocations are thus only consumed by users of the ELF
binary, such as debuggers.

So move to 'strip' for performing the relocation check, and if it succeeds,
invoke objcopy as before, but leaving the .debug sections in place. Note
that these sections may refer to ksymtab/kcrctab contents, so leave those
in place as well.

Signed-off-by: Ard Biesheuvel &lt;ard.biesheuvel@linaro.org&gt;
Cc: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Cc: Matt Fleming &lt;matt@codeblueprint.co.uk&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Cc: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Cc: linux-efi@vger.kernel.org
Link: http://lkml.kernel.org/r/1485868902-20401-11-git-send-email-ard.biesheuvel@linaro.org
Signed-off-by: Ingo Molnar &lt;mingo@kernel.org&gt;
Signed-off-by: Nick Desaulniers &lt;ndesaulniers@google.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 696204faa6e8a318320ebb49d9fa69bc8275644d upstream.

The build commands for the ARM and arm64 EFI stubs strip the .debug
sections and other sections that may legally contain absolute relocations,
in order to inspect the remaining sections for the presence of such
relocations.

This leaves us without debugging symbols in the stub for no good reason,
considering that these sections are omitted from the kernel binary anyway,
and that these relocations are thus only consumed by users of the ELF
binary, such as debuggers.

So move to 'strip' for performing the relocation check, and if it succeeds,
invoke objcopy as before, but leaving the .debug sections in place. Note
that these sections may refer to ksymtab/kcrctab contents, so leave those
in place as well.

Signed-off-by: Ard Biesheuvel &lt;ard.biesheuvel@linaro.org&gt;
Cc: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Cc: Matt Fleming &lt;matt@codeblueprint.co.uk&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Cc: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Cc: linux-efi@vger.kernel.org
Link: http://lkml.kernel.org/r/1485868902-20401-11-git-send-email-ard.biesheuvel@linaro.org
Signed-off-by: Ingo Molnar &lt;mingo@kernel.org&gt;
Signed-off-by: Nick Desaulniers &lt;ndesaulniers@google.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
</feed>
