<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux.git/arch/arm64/kernel/sys_compat.c, branch v4.19.315</title>
<subtitle>Clone of https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git</subtitle>
<link rel='alternate' type='text/html' href='https://git.exis.tech/linux.git/'/>
<entry>
<title>arm64: Silence clang warning on mismatched value/register sizes</title>
<updated>2020-04-29T14:31:09+00:00</updated>
<author>
<name>Catalin Marinas</name>
<email>catalin.marinas@arm.com</email>
</author>
<published>2020-04-24T16:38:45+00:00</published>
<link rel='alternate' type='text/html' href='https://git.exis.tech/linux.git/commit/?id=d42f91ba29e3d8b76ac7136751e0e88ddca025ed'/>
<id>d42f91ba29e3d8b76ac7136751e0e88ddca025ed</id>
<content type='text'>
[ Upstream commit: 27a22fbdeedd6c5c451cf5f830d51782bf50c3a2 ]

Clang reports a warning on the __tlbi(aside1is, 0) macro expansion since
the value size does not match the register size specified in the inline
asm. Construct the ASID value using the __TLBI_VADDR() macro.

Fixes: 222fc0c8503d ("arm64: compat: Workaround Neoverse-N1 #1542419 for compat user-space")
Reported-by: Nathan Chancellor &lt;natechancellor@gmail.com&gt;
Cc: James Morse &lt;james.morse@arm.com&gt;
Signed-off-by: Catalin Marinas &lt;catalin.marinas@arm.com&gt;
Signed-off-by: James Morse &lt;james.morse@arm.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: 27a22fbdeedd6c5c451cf5f830d51782bf50c3a2 ]

Clang reports a warning on the __tlbi(aside1is, 0) macro expansion since
the value size does not match the register size specified in the inline
asm. Construct the ASID value using the __TLBI_VADDR() macro.

Fixes: 222fc0c8503d ("arm64: compat: Workaround Neoverse-N1 #1542419 for compat user-space")
Reported-by: Nathan Chancellor &lt;natechancellor@gmail.com&gt;
Cc: James Morse &lt;james.morse@arm.com&gt;
Signed-off-by: Catalin Marinas &lt;catalin.marinas@arm.com&gt;
Signed-off-by: James Morse &lt;james.morse@arm.com&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>arm64: compat: Workaround Neoverse-N1 #1542419 for compat user-space</title>
<updated>2020-04-29T14:31:09+00:00</updated>
<author>
<name>James Morse</name>
<email>james.morse@arm.com</email>
</author>
<published>2020-04-24T16:38:44+00:00</published>
<link rel='alternate' type='text/html' href='https://git.exis.tech/linux.git/commit/?id=05a5ec4131b747b57c268cb72c6810ef6a8e653f'/>
<id>05a5ec4131b747b57c268cb72c6810ef6a8e653f</id>
<content type='text'>
[ Upstream commit: 222fc0c8503d98cec3cb2bac2780cdd21a6e31c0 ]

Compat user-space is unable to perform ICIMVAU instructions from
user-space. Instead it uses a compat-syscall. Add the workaround for
Neoverse-N1 #1542419 to this code path.

Signed-off-by: James Morse &lt;james.morse@arm.com&gt;
Signed-off-by: Catalin Marinas &lt;catalin.marinas@arm.com&gt;
Signed-off-by: James Morse &lt;james.morse@arm.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: 222fc0c8503d98cec3cb2bac2780cdd21a6e31c0 ]

Compat user-space is unable to perform ICIMVAU instructions from
user-space. Instead it uses a compat-syscall. Add the workaround for
Neoverse-N1 #1542419 to this code path.

Signed-off-by: James Morse &lt;james.morse@arm.com&gt;
Signed-off-by: Catalin Marinas &lt;catalin.marinas@arm.com&gt;
Signed-off-by: James Morse &lt;james.morse@arm.com&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>arm64: compat: Don't pull syscall number from regs in arm_compat_syscall</title>
<updated>2019-01-16T21:04:37+00:00</updated>
<author>
<name>Will Deacon</name>
<email>will.deacon@arm.com</email>
</author>
<published>2019-01-03T18:00:39+00:00</published>
<link rel='alternate' type='text/html' href='https://git.exis.tech/linux.git/commit/?id=6c9a2046297f7210498d47de9e348fe93270b099'/>
<id>6c9a2046297f7210498d47de9e348fe93270b099</id>
<content type='text'>
commit 53290432145a8eb143fe29e06e9c1465d43dc723 upstream.

The syscall number may have been changed by a tracer, so we should pass
the actual number in from the caller instead of pulling it from the
saved r7 value directly.

Cc: &lt;stable@vger.kernel.org&gt;
Cc: Pi-Hsun Shih &lt;pihsun@chromium.org&gt;
Reviewed-by: Dave Martin &lt;Dave.Martin@arm.com&gt;
Signed-off-by: Will Deacon &lt;will.deacon@arm.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 53290432145a8eb143fe29e06e9c1465d43dc723 upstream.

The syscall number may have been changed by a tracer, so we should pass
the actual number in from the caller instead of pulling it from the
saved r7 value directly.

Cc: &lt;stable@vger.kernel.org&gt;
Cc: Pi-Hsun Shih &lt;pihsun@chromium.org&gt;
Reviewed-by: Dave Martin &lt;Dave.Martin@arm.com&gt;
Signed-off-by: Will Deacon &lt;will.deacon@arm.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;


</pre>
</div>
</content>
</entry>
<entry>
<title>arm64: compat: Avoid sending SIGILL for unallocated syscall numbers</title>
<updated>2019-01-09T16:38:49+00:00</updated>
<author>
<name>Will Deacon</name>
<email>will.deacon@arm.com</email>
</author>
<published>2019-01-03T17:45:07+00:00</published>
<link rel='alternate' type='text/html' href='https://git.exis.tech/linux.git/commit/?id=920735c63d8a44c664f0967721a0081f60d37fb0'/>
<id>920735c63d8a44c664f0967721a0081f60d37fb0</id>
<content type='text'>
commit 169113ece0f29ebe884a6cfcf57c1ace04d8a36a upstream.

The ARM Linux kernel handles the EABI syscall numbers as follows:

  0           - NR_SYSCALLS-1	: Invoke syscall via syscall table
  NR_SYSCALLS - 0xeffff		: -ENOSYS (to be allocated in future)
  0xf0000     - 0xf07ff		: Private syscall or -ENOSYS if not allocated
  &gt; 0xf07ff			: SIGILL

Our compat code gets this wrong and ends up sending SIGILL in response
to all syscalls greater than NR_SYSCALLS which have a value greater
than 0x7ff in the bottom 16 bits.

Fix this by defining the end of the ARM private syscall region and
checking the syscall number against that directly. Update the comment
while we're at it.

Cc: &lt;stable@vger.kernel.org&gt;
Cc: Dave Martin &lt;Dave.Martin@arm.com&gt;
Reported-by: Pi-Hsun Shih &lt;pihsun@chromium.org&gt;
Signed-off-by: Will Deacon &lt;will.deacon@arm.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 169113ece0f29ebe884a6cfcf57c1ace04d8a36a upstream.

The ARM Linux kernel handles the EABI syscall numbers as follows:

  0           - NR_SYSCALLS-1	: Invoke syscall via syscall table
  NR_SYSCALLS - 0xeffff		: -ENOSYS (to be allocated in future)
  0xf0000     - 0xf07ff		: Private syscall or -ENOSYS if not allocated
  &gt; 0xf07ff			: SIGILL

Our compat code gets this wrong and ends up sending SIGILL in response
to all syscalls greater than NR_SYSCALLS which have a value greater
than 0x7ff in the bottom 16 bits.

Fix this by defining the end of the ARM private syscall region and
checking the syscall number against that directly. Update the comment
while we're at it.

Cc: &lt;stable@vger.kernel.org&gt;
Cc: Dave Martin &lt;Dave.Martin@arm.com&gt;
Reported-by: Pi-Hsun Shih &lt;pihsun@chromium.org&gt;
Signed-off-by: Will Deacon &lt;will.deacon@arm.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>signal: Ensure every siginfo we send has all bits initialized</title>
<updated>2018-04-25T15:40:51+00:00</updated>
<author>
<name>Eric W. Biederman</name>
<email>ebiederm@xmission.com</email>
</author>
<published>2018-04-17T20:26:37+00:00</published>
<link rel='alternate' type='text/html' href='https://git.exis.tech/linux.git/commit/?id=3eb0f5193b497083391aa05d35210d5645211eef'/>
<id>3eb0f5193b497083391aa05d35210d5645211eef</id>
<content type='text'>
Call clear_siginfo to ensure every stack allocated siginfo is properly
initialized before being passed to the signal sending functions.

Note: It is not safe to depend on C initializers to initialize struct
siginfo on the stack because C is allowed to skip holes when
initializing a structure.

The initialization of struct siginfo in tracehook_report_syscall_exit
was moved from the helper user_single_step_siginfo into
tracehook_report_syscall_exit itself, to make it clear that the local
variable siginfo gets fully initialized.

In a few cases the scope of struct siginfo has been reduced to make it
clear that siginfo siginfo is not used on other paths in the function
in which it is declared.

Instances of using memset to initialize siginfo have been replaced
with calls clear_siginfo for clarity.

Signed-off-by: "Eric W. Biederman" &lt;ebiederm@xmission.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Call clear_siginfo to ensure every stack allocated siginfo is properly
initialized before being passed to the signal sending functions.

Note: It is not safe to depend on C initializers to initialize struct
siginfo on the stack because C is allowed to skip holes when
initializing a structure.

The initialization of struct siginfo in tracehook_report_syscall_exit
was moved from the helper user_single_step_siginfo into
tracehook_report_syscall_exit itself, to make it clear that the local
variable siginfo gets fully initialized.

In a few cases the scope of struct siginfo has been reduced to make it
clear that siginfo siginfo is not used on other paths in the function
in which it is declared.

Instances of using memset to initialize siginfo have been replaced
with calls clear_siginfo for clarity.

Signed-off-by: "Eric W. Biederman" &lt;ebiederm@xmission.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>arm64: uaccess: Fix omissions from usercopy whitelist</title>
<updated>2018-03-28T14:25:44+00:00</updated>
<author>
<name>Dave Martin</name>
<email>Dave.Martin@arm.com</email>
</author>
<published>2018-03-28T09:50:49+00:00</published>
<link rel='alternate' type='text/html' href='https://git.exis.tech/linux.git/commit/?id=65896545b69ffaac947c12e11d3dcc57fd1fb772'/>
<id>65896545b69ffaac947c12e11d3dcc57fd1fb772</id>
<content type='text'>
When the hardend usercopy support was added for arm64, it was
concluded that all cases of usercopy into and out of thread_struct
were statically sized and so didn't require explicit whitelisting
of the appropriate fields in thread_struct.

Testing with usercopy hardening enabled has revealed that this is
not the case for certain ptrace regset manipulation calls on arm64.
This occurs because the sizes of usercopies associated with the
regset API are dynamic by construction, and because arm64 does not
always stage such copies via the stack: indeed the regset API is
designed to avoid the need for that by adding some bounds checking.

This is currently believed to affect only the fpsimd and TLS
registers.

Because the whitelisted fields in thread_struct must be contiguous,
this patch groups them together in a nested struct.  It is also
necessary to be able to determine the location and size of that
struct, so rather than making the struct anonymous (which would
save on edits elsewhere) or adding an anonymous union containing
named and unnamed instances of the same struct (gross), this patch
gives the struct a name and makes the necessary edits to code that
references it (noisy but simple).

Care is needed to ensure that the new struct does not contain
padding (which the usercopy hardening would fail to protect).

For this reason, the presence of tp2_value is made unconditional,
since a padding field would be needed there in any case.  This pads
up to the 16-byte alignment required by struct user_fpsimd_state.

Acked-by: Kees Cook &lt;keescook@chromium.org&gt;
Reported-by: Mark Rutland &lt;mark.rutland@arm.com&gt;
Fixes: 9e8084d3f761 ("arm64: Implement thread_struct whitelist for hardened usercopy")
Signed-off-by: Dave Martin &lt;Dave.Martin@arm.com&gt;
Signed-off-by: Will Deacon &lt;will.deacon@arm.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
When the hardend usercopy support was added for arm64, it was
concluded that all cases of usercopy into and out of thread_struct
were statically sized and so didn't require explicit whitelisting
of the appropriate fields in thread_struct.

Testing with usercopy hardening enabled has revealed that this is
not the case for certain ptrace regset manipulation calls on arm64.
This occurs because the sizes of usercopies associated with the
regset API are dynamic by construction, and because arm64 does not
always stage such copies via the stack: indeed the regset API is
designed to avoid the need for that by adding some bounds checking.

This is currently believed to affect only the fpsimd and TLS
registers.

Because the whitelisted fields in thread_struct must be contiguous,
this patch groups them together in a nested struct.  It is also
necessary to be able to determine the location and size of that
struct, so rather than making the struct anonymous (which would
save on edits elsewhere) or adding an anonymous union containing
named and unnamed instances of the same struct (gross), this patch
gives the struct a name and makes the necessary edits to code that
references it (noisy but simple).

Care is needed to ensure that the new struct does not contain
padding (which the usercopy hardening would fail to protect).

For this reason, the presence of tp2_value is made unconditional,
since a padding field would be needed there in any case.  This pads
up to the 16-byte alignment required by struct user_fpsimd_state.

Acked-by: Kees Cook &lt;keescook@chromium.org&gt;
Reported-by: Mark Rutland &lt;mark.rutland@arm.com&gt;
Fixes: 9e8084d3f761 ("arm64: Implement thread_struct whitelist for hardened usercopy")
Signed-off-by: Dave Martin &lt;Dave.Martin@arm.com&gt;
Signed-off-by: Will Deacon &lt;will.deacon@arm.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>arm64: Mirror arm for unimplemented compat syscalls</title>
<updated>2018-03-05T12:06:43+00:00</updated>
<author>
<name>Michael Weiser</name>
<email>michael.weiser@gmx.de</email>
</author>
<published>2018-02-01T22:13:37+00:00</published>
<link rel='alternate' type='text/html' href='https://git.exis.tech/linux.git/commit/?id=532826f3712b607256eb30f92f23d1c604d3fa34'/>
<id>532826f3712b607256eb30f92f23d1c604d3fa34</id>
<content type='text'>
Mirror arm behaviour for unimplemented syscalls: Below 2048 return
-ENOSYS, above 2048 raise SIGILL.

Signed-off-by: Michael Weiser &lt;michael.weiser@gmx.de&gt;
[will: Tweak die string to identify as compat syscall]
Signed-off-by: Will Deacon &lt;will.deacon@arm.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Mirror arm behaviour for unimplemented syscalls: Below 2048 return
-ENOSYS, above 2048 raise SIGILL.

Signed-off-by: Michael Weiser &lt;michael.weiser@gmx.de&gt;
[will: Tweak die string to identify as compat syscall]
Signed-off-by: Will Deacon &lt;will.deacon@arm.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>arm64: uaccess: Formalise types for access_ok()</title>
<updated>2018-02-19T13:59:58+00:00</updated>
<author>
<name>Robin Murphy</name>
<email>robin.murphy@arm.com</email>
</author>
<published>2018-02-19T13:38:00+00:00</published>
<link rel='alternate' type='text/html' href='https://git.exis.tech/linux.git/commit/?id=9085b34d0e8361595a7d19034c550d5d15044556'/>
<id>9085b34d0e8361595a7d19034c550d5d15044556</id>
<content type='text'>
In converting __range_ok() into a static inline, I inadvertently made
it more type-safe, but without considering the ordering of the relevant
conversions. This leads to quite a lot of Sparse noise about the fact
that we use __chk_user_ptr() after addr has already been converted from
a user pointer to an unsigned long.

Rather than just adding another cast for the sake of shutting Sparse up,
it seems reasonable to rework the types to make logical sense (although
the resulting codegen for __range_ok() remains identical). The only
callers this affects directly are our compat traps where the inferred
"user-pointer-ness" of a register value now warrants explicit casting.

Signed-off-by: Robin Murphy &lt;robin.murphy@arm.com&gt;
Signed-off-by: Catalin Marinas &lt;catalin.marinas@arm.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
In converting __range_ok() into a static inline, I inadvertently made
it more type-safe, but without considering the ordering of the relevant
conversions. This leads to quite a lot of Sparse noise about the fact
that we use __chk_user_ptr() after addr has already been converted from
a user pointer to an unsigned long.

Rather than just adding another cast for the sake of shutting Sparse up,
it seems reasonable to rework the types to make logical sense (although
the resulting codegen for __range_ok() remains identical). The only
callers this affects directly are our compat traps where the inferred
"user-pointer-ness" of a register value now warrants explicit casting.

Signed-off-by: Robin Murphy &lt;robin.murphy@arm.com&gt;
Signed-off-by: Catalin Marinas &lt;catalin.marinas@arm.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>sched/headers: Prepare for the reduction of &lt;linux/sched.h&gt;'s signal API dependency</title>
<updated>2017-03-02T07:42:37+00:00</updated>
<author>
<name>Ingo Molnar</name>
<email>mingo@kernel.org</email>
</author>
<published>2017-02-03T22:47:37+00:00</published>
<link rel='alternate' type='text/html' href='https://git.exis.tech/linux.git/commit/?id=f361bf4a66c9bfabace46f6ff5d97005c9b524fe'/>
<id>f361bf4a66c9bfabace46f6ff5d97005c9b524fe</id>
<content type='text'>
Instead of including the full &lt;linux/signal.h&gt;, we are going to include the
types-only &lt;linux/signal_types.h&gt; header in &lt;linux/sched.h&gt;, to further
decouple the scheduler header from the signal headers.

This means that various files which relied on the full &lt;linux/signal.h&gt; need
to be updated to gain an explicit dependency on it.

Update the code that relies on sched.h's inclusion of the &lt;linux/signal.h&gt; header.

Acked-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Cc: Mike Galbraith &lt;efault@gmx.de&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Cc: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar &lt;mingo@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Instead of including the full &lt;linux/signal.h&gt;, we are going to include the
types-only &lt;linux/signal_types.h&gt; header in &lt;linux/sched.h&gt;, to further
decouple the scheduler header from the signal headers.

This means that various files which relied on the full &lt;linux/signal.h&gt; need
to be updated to gain an explicit dependency on it.

Update the code that relies on sched.h's inclusion of the &lt;linux/signal.h&gt; header.

Acked-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Cc: Mike Galbraith &lt;efault@gmx.de&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Cc: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar &lt;mingo@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>arm64: simplify sysreg manipulation</title>
<updated>2016-09-09T10:43:50+00:00</updated>
<author>
<name>Mark Rutland</name>
<email>mark.rutland@arm.com</email>
</author>
<published>2016-09-08T12:55:38+00:00</published>
<link rel='alternate' type='text/html' href='https://git.exis.tech/linux.git/commit/?id=adf7589997927b1d84a5d003027b866bbef61ef2'/>
<id>adf7589997927b1d84a5d003027b866bbef61ef2</id>
<content type='text'>
A while back we added {read,write}_sysreg accessors to handle accesses
to system registers, without the usual boilerplate asm volatile,
temporary variable, etc.

This patch makes use of these across arm64 to make code shorter and
clearer. For sequences with a trailing ISB, the existing isb() macro is
also used so that asm blocks can be removed entirely.

A few uses of inline assembly for msr/mrs are left as-is. Those
manipulating sp_el0 for the current thread_info value have special
clobber requiremends.

Signed-off-by: Mark Rutland &lt;mark.rutland@arm.com&gt;
Cc: Catalin Marinas &lt;catalin.marinas@arm.com&gt;
Cc: Will Deacon &lt;will.deacon@arm.com&gt;
Signed-off-by: Will Deacon &lt;will.deacon@arm.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
A while back we added {read,write}_sysreg accessors to handle accesses
to system registers, without the usual boilerplate asm volatile,
temporary variable, etc.

This patch makes use of these across arm64 to make code shorter and
clearer. For sequences with a trailing ISB, the existing isb() macro is
also used so that asm blocks can be removed entirely.

A few uses of inline assembly for msr/mrs are left as-is. Those
manipulating sp_el0 for the current thread_info value have special
clobber requiremends.

Signed-off-by: Mark Rutland &lt;mark.rutland@arm.com&gt;
Cc: Catalin Marinas &lt;catalin.marinas@arm.com&gt;
Cc: Will Deacon &lt;will.deacon@arm.com&gt;
Signed-off-by: Will Deacon &lt;will.deacon@arm.com&gt;
</pre>
</div>
</content>
</entry>
</feed>
