<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux-toradex.git/arch, branch v4.4.78</title>
<subtitle>Linux kernel for Apalis and Colibri modules</subtitle>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/'/>
<entry>
<title>kvm: vmx: allow host to access guest MSR_IA32_BNDCFGS</title>
<updated>2017-07-21T05:45:00+00:00</updated>
<author>
<name>Haozhong Zhang</name>
<email>haozhong.zhang@intel.com</email>
</author>
<published>2017-07-04T02:27:41+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=3ed43caedf69a6fd417bdda174eb8fa06b3b5dab'/>
<id>3ed43caedf69a6fd417bdda174eb8fa06b3b5dab</id>
<content type='text'>
commit 691bd4340bef49cf7e5855d06cf24444b5bf2d85 upstream.

It's easier for host applications, such as QEMU, if they can always
access guest MSR_IA32_BNDCFGS in VMCS, even though MPX is disabled in
guest cpuid.

Signed-off-by: Haozhong Zhang &lt;haozhong.zhang@intel.com&gt;
Signed-off-by: Paolo Bonzini &lt;pbonzini@redhat.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 691bd4340bef49cf7e5855d06cf24444b5bf2d85 upstream.

It's easier for host applications, such as QEMU, if they can always
access guest MSR_IA32_BNDCFGS in VMCS, even though MPX is disabled in
guest cpuid.

Signed-off-by: Haozhong Zhang &lt;haozhong.zhang@intel.com&gt;
Signed-off-by: Paolo Bonzini &lt;pbonzini@redhat.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>kvm: vmx: Check value written to IA32_BNDCFGS</title>
<updated>2017-07-21T05:44:59+00:00</updated>
<author>
<name>Jim Mattson</name>
<email>jmattson@google.com</email>
</author>
<published>2017-05-23T18:52:54+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=6ffa92ffaed817cea7625ebf9c7f217e293923be'/>
<id>6ffa92ffaed817cea7625ebf9c7f217e293923be</id>
<content type='text'>
commit 4531662d1abf6c1f0e5c2b86ddb60e61509786c8 upstream.

Bits 11:2 must be zero and the linear addess in bits 63:12 must be
canonical. Otherwise, WRMSR(BNDCFGS) should raise #GP.

Fixes: 0dd376e709975779 ("KVM: x86: add MSR_IA32_BNDCFGS to msrs_to_save")
Signed-off-by: Jim Mattson &lt;jmattson@google.com&gt;
Signed-off-by: Radim Krčmář &lt;rkrcmar@redhat.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 4531662d1abf6c1f0e5c2b86ddb60e61509786c8 upstream.

Bits 11:2 must be zero and the linear addess in bits 63:12 must be
canonical. Otherwise, WRMSR(BNDCFGS) should raise #GP.

Fixes: 0dd376e709975779 ("KVM: x86: add MSR_IA32_BNDCFGS to msrs_to_save")
Signed-off-by: Jim Mattson &lt;jmattson@google.com&gt;
Signed-off-by: Radim Krčmář &lt;rkrcmar@redhat.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>kvm: x86: Guest BNDCFGS requires guest MPX support</title>
<updated>2017-07-21T05:44:59+00:00</updated>
<author>
<name>Jim Mattson</name>
<email>jmattson@google.com</email>
</author>
<published>2017-05-24T17:49:25+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=a40f0ccd4f1c2751d5df5d9a63b9cf93ff70d343'/>
<id>a40f0ccd4f1c2751d5df5d9a63b9cf93ff70d343</id>
<content type='text'>
commit 4439af9f911ae0243ffe4e2dfc12bace49605d8b upstream.

The BNDCFGS MSR should only be exposed to the guest if the guest
supports MPX. (cf. the TSC_AUX MSR and RDTSCP.)

Fixes: 0dd376e709975779 ("KVM: x86: add MSR_IA32_BNDCFGS to msrs_to_save")
Change-Id: I3ad7c01bda616715137ceac878f3fa7e66b6b387
Signed-off-by: Jim Mattson &lt;jmattson@google.com&gt;
Signed-off-by: Radim Krčmář &lt;rkrcmar@redhat.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 4439af9f911ae0243ffe4e2dfc12bace49605d8b upstream.

The BNDCFGS MSR should only be exposed to the guest if the guest
supports MPX. (cf. the TSC_AUX MSR and RDTSCP.)

Fixes: 0dd376e709975779 ("KVM: x86: add MSR_IA32_BNDCFGS to msrs_to_save")
Change-Id: I3ad7c01bda616715137ceac878f3fa7e66b6b387
Signed-off-by: Jim Mattson &lt;jmattson@google.com&gt;
Signed-off-by: Radim Krčmář &lt;rkrcmar@redhat.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>kvm: vmx: Do not disable intercepts for BNDCFGS</title>
<updated>2017-07-21T05:44:59+00:00</updated>
<author>
<name>Jim Mattson</name>
<email>jmattson@google.com</email>
</author>
<published>2017-05-23T18:52:52+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=be6f33a61f335cb06b3c8c2cee90214f97c4bda3'/>
<id>be6f33a61f335cb06b3c8c2cee90214f97c4bda3</id>
<content type='text'>
commit a8b6fda38f80e75afa3b125c9e7f2550b579454b upstream.

The MSR permission bitmaps are shared by all VMs. However, some VMs
may not be configured to support MPX, even when the host does. If the
host supports VMX and the guest does not, we should intercept accesses
to the BNDCFGS MSR, so that we can synthesize a #GP
fault. Furthermore, if the host does not support MPX and the
"ignore_msrs" kvm kernel parameter is set, then we should intercept
accesses to the BNDCFGS MSR, so that we can skip over the rdmsr/wrmsr
without raising a #GP fault.

Fixes: da8999d31818fdc8 ("KVM: x86: Intel MPX vmx and msr handle")
Signed-off-by: Jim Mattson &lt;jmattson@google.com&gt;
Signed-off-by: Radim Krčmář &lt;rkrcmar@redhat.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 a8b6fda38f80e75afa3b125c9e7f2550b579454b upstream.

The MSR permission bitmaps are shared by all VMs. However, some VMs
may not be configured to support MPX, even when the host does. If the
host supports VMX and the guest does not, we should intercept accesses
to the BNDCFGS MSR, so that we can synthesize a #GP
fault. Furthermore, if the host does not support MPX and the
"ignore_msrs" kvm kernel parameter is set, then we should intercept
accesses to the BNDCFGS MSR, so that we can skip over the rdmsr/wrmsr
without raising a #GP fault.

Fixes: da8999d31818fdc8 ("KVM: x86: Intel MPX vmx and msr handle")
Signed-off-by: Jim Mattson &lt;jmattson@google.com&gt;
Signed-off-by: Radim Krčmář &lt;rkrcmar@redhat.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>KVM: x86: disable MPX if host did not enable MPX XSAVE features</title>
<updated>2017-07-21T05:44:59+00:00</updated>
<author>
<name>Paolo Bonzini</name>
<email>pbonzini@redhat.com</email>
</author>
<published>2016-03-08T08:52:13+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=c6f3576ed0f21058629d5461eb014c1e0e3f7c4d'/>
<id>c6f3576ed0f21058629d5461eb014c1e0e3f7c4d</id>
<content type='text'>
commit a87036add09283e6c4f4103a15c596c67b86ab86 upstream.

When eager FPU is disabled, KVM will still see the MPX bit in CPUID and
presumably the MPX vmentry and vmexit controls.  However, it will not
be able to expose the MPX XSAVE features to the guest, because the guest's
accessible XSAVE features are always a subset of host_xcr0.

In this case, we should disable the MPX CPUID bit, the BNDCFGS MSR,
and the MPX vmentry and vmexit controls for nested virtualization.
It is then unnecessary to enable guest eager FPU if the guest has the
MPX CPUID bit set.

Signed-off-by: Paolo Bonzini &lt;pbonzini@redhat.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 a87036add09283e6c4f4103a15c596c67b86ab86 upstream.

When eager FPU is disabled, KVM will still see the MPX bit in CPUID and
presumably the MPX vmentry and vmexit controls.  However, it will not
be able to expose the MPX XSAVE features to the guest, because the guest's
accessible XSAVE features are always a subset of host_xcr0.

In this case, we should disable the MPX CPUID bit, the BNDCFGS MSR,
and the MPX vmentry and vmexit controls for nested virtualization.
It is then unnecessary to enable guest eager FPU if the guest has the
MPX CPUID bit set.

Signed-off-by: Paolo Bonzini &lt;pbonzini@redhat.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>crypto: sha1-ssse3 - Disable avx2</title>
<updated>2017-07-21T05:44:58+00:00</updated>
<author>
<name>Herbert Xu</name>
<email>herbert@gondor.apana.org.au</email>
</author>
<published>2017-07-04T04:21:12+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=f1bf5d83a9c17b739f2a944e3686d6b97693e67f'/>
<id>f1bf5d83a9c17b739f2a944e3686d6b97693e67f</id>
<content type='text'>
commit b82ce24426a4071da9529d726057e4e642948667 upstream.

It has been reported that sha1-avx2 can cause page faults by reading
beyond the end of the input.  This patch disables it until it can be
fixed.

Fixes: 7c1da8d0d046 ("crypto: sha - SHA1 transform x86_64 AVX2")
Reported-by: Jan Stancek &lt;jstancek@redhat.com&gt;
Signed-off-by: Herbert Xu &lt;herbert@gondor.apana.org.au&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 b82ce24426a4071da9529d726057e4e642948667 upstream.

It has been reported that sha1-avx2 can cause page faults by reading
beyond the end of the input.  This patch disables it until it can be
fixed.

Fixes: 7c1da8d0d046 ("crypto: sha - SHA1 transform x86_64 AVX2")
Reported-by: Jan Stancek &lt;jstancek@redhat.com&gt;
Signed-off-by: Herbert Xu &lt;herbert@gondor.apana.org.au&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>s390: reduce ELF_ET_DYN_BASE</title>
<updated>2017-07-21T05:44:57+00:00</updated>
<author>
<name>Kees Cook</name>
<email>keescook@chromium.org</email>
</author>
<published>2017-07-10T22:52:51+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=7888c0296c87a6c83bf2a0311c8e929f5f11832f'/>
<id>7888c0296c87a6c83bf2a0311c8e929f5f11832f</id>
<content type='text'>
commit a73dc5370e153ac63718d850bddf0c9aa9d871e6 upstream.

Now that explicitly executed loaders are loaded in the mmap region, we
have more freedom to decide where we position PIE binaries in the
address space to avoid possible collisions with mmap or stack regions.

For 64-bit, align to 4GB to allow runtimes to use the entire 32-bit
address space for 32-bit pointers.  On 32-bit use 4MB, which is the
traditional x86 minimum load location, likely to avoid historically
requiring a 4MB page table entry when only a portion of the first 4MB
would be used (since the NULL address is avoided).  For s390 the
position could be 0x10000, but that is needlessly close to the NULL
address.

Link: http://lkml.kernel.org/r/1498154792-49952-5-git-send-email-keescook@chromium.org
Signed-off-by: Kees Cook &lt;keescook@chromium.org&gt;
Cc: Russell King &lt;linux@armlinux.org.uk&gt;
Cc: Catalin Marinas &lt;catalin.marinas@arm.com&gt;
Cc: Will Deacon &lt;will.deacon@arm.com&gt;
Cc: Benjamin Herrenschmidt &lt;benh@kernel.crashing.org&gt;
Cc: Paul Mackerras &lt;paulus@samba.org&gt;
Cc: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
Cc: Martin Schwidefsky &lt;schwidefsky@de.ibm.com&gt;
Cc: Heiko Carstens &lt;heiko.carstens@de.ibm.com&gt;
Cc: James Hogan &lt;james.hogan@imgtec.com&gt;
Cc: Pratyush Anand &lt;panand@redhat.com&gt;
Cc: Ingo Molnar &lt;mingo@kernel.org&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.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 a73dc5370e153ac63718d850bddf0c9aa9d871e6 upstream.

Now that explicitly executed loaders are loaded in the mmap region, we
have more freedom to decide where we position PIE binaries in the
address space to avoid possible collisions with mmap or stack regions.

For 64-bit, align to 4GB to allow runtimes to use the entire 32-bit
address space for 32-bit pointers.  On 32-bit use 4MB, which is the
traditional x86 minimum load location, likely to avoid historically
requiring a 4MB page table entry when only a portion of the first 4MB
would be used (since the NULL address is avoided).  For s390 the
position could be 0x10000, but that is needlessly close to the NULL
address.

Link: http://lkml.kernel.org/r/1498154792-49952-5-git-send-email-keescook@chromium.org
Signed-off-by: Kees Cook &lt;keescook@chromium.org&gt;
Cc: Russell King &lt;linux@armlinux.org.uk&gt;
Cc: Catalin Marinas &lt;catalin.marinas@arm.com&gt;
Cc: Will Deacon &lt;will.deacon@arm.com&gt;
Cc: Benjamin Herrenschmidt &lt;benh@kernel.crashing.org&gt;
Cc: Paul Mackerras &lt;paulus@samba.org&gt;
Cc: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
Cc: Martin Schwidefsky &lt;schwidefsky@de.ibm.com&gt;
Cc: Heiko Carstens &lt;heiko.carstens@de.ibm.com&gt;
Cc: James Hogan &lt;james.hogan@imgtec.com&gt;
Cc: Pratyush Anand &lt;panand@redhat.com&gt;
Cc: Ingo Molnar &lt;mingo@kernel.org&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>powerpc: move ELF_ET_DYN_BASE to 4GB / 4MB</title>
<updated>2017-07-21T05:44:57+00:00</updated>
<author>
<name>Kees Cook</name>
<email>keescook@chromium.org</email>
</author>
<published>2017-07-10T22:52:47+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=72a333a0468ed9c492c4da6b017aac9456695c7a'/>
<id>72a333a0468ed9c492c4da6b017aac9456695c7a</id>
<content type='text'>
commit 47ebb09d54856500c5a5e14824781902b3bb738e upstream.

Now that explicitly executed loaders are loaded in the mmap region, we
have more freedom to decide where we position PIE binaries in the
address space to avoid possible collisions with mmap or stack regions.

For 64-bit, align to 4GB to allow runtimes to use the entire 32-bit
address space for 32-bit pointers.  On 32-bit use 4MB, which is the
traditional x86 minimum load location, likely to avoid historically
requiring a 4MB page table entry when only a portion of the first 4MB
would be used (since the NULL address is avoided).

Link: http://lkml.kernel.org/r/1498154792-49952-4-git-send-email-keescook@chromium.org
Signed-off-by: Kees Cook &lt;keescook@chromium.org&gt;
Tested-by: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
Acked-by: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
Cc: Russell King &lt;linux@armlinux.org.uk&gt;
Cc: Catalin Marinas &lt;catalin.marinas@arm.com&gt;
Cc: Will Deacon &lt;will.deacon@arm.com&gt;
Cc: Benjamin Herrenschmidt &lt;benh@kernel.crashing.org&gt;
Cc: Paul Mackerras &lt;paulus@samba.org&gt;
Cc: Martin Schwidefsky &lt;schwidefsky@de.ibm.com&gt;
Cc: Heiko Carstens &lt;heiko.carstens@de.ibm.com&gt;
Cc: James Hogan &lt;james.hogan@imgtec.com&gt;
Cc: Pratyush Anand &lt;panand@redhat.com&gt;
Cc: Ingo Molnar &lt;mingo@kernel.org&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.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 47ebb09d54856500c5a5e14824781902b3bb738e upstream.

Now that explicitly executed loaders are loaded in the mmap region, we
have more freedom to decide where we position PIE binaries in the
address space to avoid possible collisions with mmap or stack regions.

For 64-bit, align to 4GB to allow runtimes to use the entire 32-bit
address space for 32-bit pointers.  On 32-bit use 4MB, which is the
traditional x86 minimum load location, likely to avoid historically
requiring a 4MB page table entry when only a portion of the first 4MB
would be used (since the NULL address is avoided).

Link: http://lkml.kernel.org/r/1498154792-49952-4-git-send-email-keescook@chromium.org
Signed-off-by: Kees Cook &lt;keescook@chromium.org&gt;
Tested-by: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
Acked-by: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
Cc: Russell King &lt;linux@armlinux.org.uk&gt;
Cc: Catalin Marinas &lt;catalin.marinas@arm.com&gt;
Cc: Will Deacon &lt;will.deacon@arm.com&gt;
Cc: Benjamin Herrenschmidt &lt;benh@kernel.crashing.org&gt;
Cc: Paul Mackerras &lt;paulus@samba.org&gt;
Cc: Martin Schwidefsky &lt;schwidefsky@de.ibm.com&gt;
Cc: Heiko Carstens &lt;heiko.carstens@de.ibm.com&gt;
Cc: James Hogan &lt;james.hogan@imgtec.com&gt;
Cc: Pratyush Anand &lt;panand@redhat.com&gt;
Cc: Ingo Molnar &lt;mingo@kernel.org&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>arm64: move ELF_ET_DYN_BASE to 4GB / 4MB</title>
<updated>2017-07-21T05:44:57+00:00</updated>
<author>
<name>Kees Cook</name>
<email>keescook@chromium.org</email>
</author>
<published>2017-07-10T22:52:44+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=43cf90f788aca3fc66d3cf5b03827bafecd2de24'/>
<id>43cf90f788aca3fc66d3cf5b03827bafecd2de24</id>
<content type='text'>
commit 02445990a96e60a67526510d8b00f7e3d14101c3 upstream.

Now that explicitly executed loaders are loaded in the mmap region, we
have more freedom to decide where we position PIE binaries in the
address space to avoid possible collisions with mmap or stack regions.

For 64-bit, align to 4GB to allow runtimes to use the entire 32-bit
address space for 32-bit pointers.  On 32-bit use 4MB, to match ARM.
This could be 0x8000, the standard ET_EXEC load address, but that is
needlessly close to the NULL address, and anyone running arm compat PIE
will have an MMU, so the tight mapping is not needed.

Link: http://lkml.kernel.org/r/1498251600-132458-4-git-send-email-keescook@chromium.org
Signed-off-by: Kees Cook &lt;keescook@chromium.org&gt;
Cc: Ard Biesheuvel &lt;ard.biesheuvel@linaro.org&gt;
Cc: Catalin Marinas &lt;catalin.marinas@arm.com&gt;
Cc: Mark Rutland &lt;mark.rutland@arm.com&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.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 02445990a96e60a67526510d8b00f7e3d14101c3 upstream.

Now that explicitly executed loaders are loaded in the mmap region, we
have more freedom to decide where we position PIE binaries in the
address space to avoid possible collisions with mmap or stack regions.

For 64-bit, align to 4GB to allow runtimes to use the entire 32-bit
address space for 32-bit pointers.  On 32-bit use 4MB, to match ARM.
This could be 0x8000, the standard ET_EXEC load address, but that is
needlessly close to the NULL address, and anyone running arm compat PIE
will have an MMU, so the tight mapping is not needed.

Link: http://lkml.kernel.org/r/1498251600-132458-4-git-send-email-keescook@chromium.org
Signed-off-by: Kees Cook &lt;keescook@chromium.org&gt;
Cc: Ard Biesheuvel &lt;ard.biesheuvel@linaro.org&gt;
Cc: Catalin Marinas &lt;catalin.marinas@arm.com&gt;
Cc: Mark Rutland &lt;mark.rutland@arm.com&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>arm: move ELF_ET_DYN_BASE to 4MB</title>
<updated>2017-07-21T05:44:57+00:00</updated>
<author>
<name>Kees Cook</name>
<email>keescook@chromium.org</email>
</author>
<published>2017-07-10T22:52:40+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=d2471b5e84f32de4e09b58f5436a4ce3ee935e32'/>
<id>d2471b5e84f32de4e09b58f5436a4ce3ee935e32</id>
<content type='text'>
commit 6a9af90a3bcde217a1c053e135f5f43e5d5fafbd upstream.

Now that explicitly executed loaders are loaded in the mmap region, we
have more freedom to decide where we position PIE binaries in the
address space to avoid possible collisions with mmap or stack regions.

4MB is chosen here mainly to have parity with x86, where this is the
traditional minimum load location, likely to avoid historically
requiring a 4MB page table entry when only a portion of the first 4MB
would be used (since the NULL address is avoided).

For ARM the position could be 0x8000, the standard ET_EXEC load address,
but that is needlessly close to the NULL address, and anyone running PIE
on 32-bit ARM will have an MMU, so the tight mapping is not needed.

Link: http://lkml.kernel.org/r/1498154792-49952-2-git-send-email-keescook@chromium.org
Signed-off-by: Kees Cook &lt;keescook@chromium.org&gt;
Cc: Russell King &lt;linux@armlinux.org.uk&gt;
Cc: Catalin Marinas &lt;catalin.marinas@arm.com&gt;
Cc: Will Deacon &lt;will.deacon@arm.com&gt;
Cc: Benjamin Herrenschmidt &lt;benh@kernel.crashing.org&gt;
Cc: Paul Mackerras &lt;paulus@samba.org&gt;
Cc: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
Cc: Martin Schwidefsky &lt;schwidefsky@de.ibm.com&gt;
Cc: Heiko Carstens &lt;heiko.carstens@de.ibm.com&gt;
Cc: James Hogan &lt;james.hogan@imgtec.com&gt;
Cc: Pratyush Anand &lt;panand@redhat.com&gt;
Cc: Ingo Molnar &lt;mingo@kernel.org&gt;
Cc: "H. Peter Anvin" &lt;hpa@zytor.com&gt;
Cc: Alexander Viro &lt;viro@zeniv.linux.org.uk&gt;
Cc: Andy Lutomirski &lt;luto@amacapital.net&gt;
Cc: Daniel Micay &lt;danielmicay@gmail.com&gt;
Cc: Dmitry Safonov &lt;dsafonov@virtuozzo.com&gt;
Cc: Grzegorz Andrejczuk &lt;grzegorz.andrejczuk@intel.com&gt;
Cc: Kees Cook &lt;keescook@chromium.org&gt;
Cc: Masahiro Yamada &lt;yamada.masahiro@socionext.com&gt;
Cc: Qualys Security Advisory &lt;qsa@qualys.com&gt;
Cc: Rik van Riel &lt;riel@redhat.com&gt;
Cc: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.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 6a9af90a3bcde217a1c053e135f5f43e5d5fafbd upstream.

Now that explicitly executed loaders are loaded in the mmap region, we
have more freedom to decide where we position PIE binaries in the
address space to avoid possible collisions with mmap or stack regions.

4MB is chosen here mainly to have parity with x86, where this is the
traditional minimum load location, likely to avoid historically
requiring a 4MB page table entry when only a portion of the first 4MB
would be used (since the NULL address is avoided).

For ARM the position could be 0x8000, the standard ET_EXEC load address,
but that is needlessly close to the NULL address, and anyone running PIE
on 32-bit ARM will have an MMU, so the tight mapping is not needed.

Link: http://lkml.kernel.org/r/1498154792-49952-2-git-send-email-keescook@chromium.org
Signed-off-by: Kees Cook &lt;keescook@chromium.org&gt;
Cc: Russell King &lt;linux@armlinux.org.uk&gt;
Cc: Catalin Marinas &lt;catalin.marinas@arm.com&gt;
Cc: Will Deacon &lt;will.deacon@arm.com&gt;
Cc: Benjamin Herrenschmidt &lt;benh@kernel.crashing.org&gt;
Cc: Paul Mackerras &lt;paulus@samba.org&gt;
Cc: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
Cc: Martin Schwidefsky &lt;schwidefsky@de.ibm.com&gt;
Cc: Heiko Carstens &lt;heiko.carstens@de.ibm.com&gt;
Cc: James Hogan &lt;james.hogan@imgtec.com&gt;
Cc: Pratyush Anand &lt;panand@redhat.com&gt;
Cc: Ingo Molnar &lt;mingo@kernel.org&gt;
Cc: "H. Peter Anvin" &lt;hpa@zytor.com&gt;
Cc: Alexander Viro &lt;viro@zeniv.linux.org.uk&gt;
Cc: Andy Lutomirski &lt;luto@amacapital.net&gt;
Cc: Daniel Micay &lt;danielmicay@gmail.com&gt;
Cc: Dmitry Safonov &lt;dsafonov@virtuozzo.com&gt;
Cc: Grzegorz Andrejczuk &lt;grzegorz.andrejczuk@intel.com&gt;
Cc: Kees Cook &lt;keescook@chromium.org&gt;
Cc: Masahiro Yamada &lt;yamada.masahiro@socionext.com&gt;
Cc: Qualys Security Advisory &lt;qsa@qualys.com&gt;
Cc: Rik van Riel &lt;riel@redhat.com&gt;
Cc: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</pre>
</div>
</content>
</entry>
</feed>
