<feed xmlns='http://www.w3.org/2005/Atom'>
<title>user/sven/linux.git/include/linux/compat.h, branch v4.20.13</title>
<subtitle>Linux Kernel
</subtitle>
<id>https://git.stealer.net/cgit.cgi/user/sven/linux.git/atom?h=v4.20.13</id>
<link rel='self' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/atom?h=v4.20.13'/>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/'/>
<updated>2018-11-03T22:42:16Z</updated>
<entry>
<title>Merge branch 'core/urgent' into x86/urgent, to pick up objtool fix</title>
<updated>2018-11-03T22:42:16Z</updated>
<author>
<name>Ingo Molnar</name>
<email>mingo@kernel.org</email>
</author>
<published>2018-11-03T22:42:16Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=23a12ddee1ce28065b71f14ccc695b5a0c8a64ff'/>
<id>urn:sha1:23a12ddee1ce28065b71f14ccc695b5a0c8a64ff</id>
<content type='text'>
Signed-off-by: Ingo Molnar &lt;mingo@kernel.org&gt;
</content>
</entry>
<entry>
<title>x86/compat: Adjust in_compat_syscall() to generic code under !COMPAT</title>
<updated>2018-11-01T11:59:25Z</updated>
<author>
<name>Dmitry Safonov</name>
<email>dima@arista.com</email>
</author>
<published>2018-10-12T13:42:52Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=a846446b1914d1e3d996d657754f43fde89bab51'/>
<id>urn:sha1:a846446b1914d1e3d996d657754f43fde89bab51</id>
<content type='text'>
The result of in_compat_syscall() can be pictured as:

x86 platform:
    ---------------------------------------------------
    |  Arch\syscall  |  64-bit  |   ia32   |   x32    |
    |-------------------------------------------------|
    |     x86_64     |  false   |   true   |   true   |
    |-------------------------------------------------|
    |      i686      |          |  &lt;true&gt;  |          |
    ---------------------------------------------------

Other platforms:
    -------------------------------------------
    |  Arch\syscall  |  64-bit  |   compat    |
    |-----------------------------------------|
    |     64-bit     |  false   |    true     |
    |-----------------------------------------|
    |    32-bit(?)   |          |   &lt;false&gt;   |
    -------------------------------------------

As seen, the result of in_compat_syscall() on generic 32-bit platform
differs from i686.

There is no reason for in_compat_syscall() == true on native i686.  It also
easy to misread code if the result on native 32-bit platform differs
between arches.

Because of that non arch-specific code has many places with:
    if (IS_ENABLED(CONFIG_COMPAT) &amp;&amp; in_compat_syscall())
in different variations.

It looks-like the only non-x86 code which uses in_compat_syscall() not
under CONFIG_COMPAT guard is in amd/amdkfd. But according to the commit
a18069c132cb ("amdkfd: Disable support for 32-bit user processes"), it
actually should be disabled on native i686.

Rename in_compat_syscall() to in_32bit_syscall() for x86-specific code
and make in_compat_syscall() false under !CONFIG_COMPAT.

A follow on patch will clean up generic users which were forced to check
IS_ENABLED(CONFIG_COMPAT) with in_compat_syscall().

Signed-off-by: Dmitry Safonov &lt;dima@arista.com&gt;
Signed-off-by: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Reviewed-by: Andy Lutomirski &lt;luto@kernel.org&gt;
Cc: Dmitry Safonov &lt;0x7f454c46@gmail.com&gt;
Cc: Ard Biesheuvel &lt;ard.biesheuvel@linaro.org&gt;
Cc: "David S. Miller" &lt;davem@davemloft.net&gt;
Cc: Herbert Xu &lt;herbert@gondor.apana.org.au&gt;
Cc: "H. Peter Anvin" &lt;hpa@zytor.com&gt;
Cc: John Stultz &lt;john.stultz@linaro.org&gt;
Cc: "Kirill A. Shutemov" &lt;kirill.shutemov@linux.intel.com&gt;
Cc: Oleg Nesterov &lt;oleg@redhat.com&gt;
Cc: Steffen Klassert &lt;steffen.klassert@secunet.com&gt;
Cc: Stephen Boyd &lt;sboyd@kernel.org&gt;
Cc: Steven Rostedt &lt;rostedt@goodmis.org&gt;
Cc: linux-efi@vger.kernel.org
Cc: netdev@vger.kernel.org
Link: https://lkml.kernel.org/r/20181012134253.23266-2-dima@arista.com

</content>
</entry>
<entry>
<title>include/linux/compat.h: mark expected switch fall-throughs</title>
<updated>2018-10-31T15:54:13Z</updated>
<author>
<name>Gustavo A. R. Silva</name>
<email>gustavo@embeddedor.com</email>
</author>
<published>2018-10-30T22:05:49Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=89976005536c47a788bdd6cef5a4e9fef3c0de32'/>
<id>urn:sha1:89976005536c47a788bdd6cef5a4e9fef3c0de32</id>
<content type='text'>
In preparation to enabling -Wimplicit-fallthrough, mark switch cases where
we are expecting to fall through.

Link: http://lkml.kernel.org/r/20181013115048.GA3262@embeddedor.com
Signed-off-by: Gustavo A. R. Silva &lt;gustavo@embeddedor.com&gt;
Acked-by: Kees Cook &lt;keescook@chromium.org&gt;
Cc: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</content>
</entry>
<entry>
<title>Merge branch 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip</title>
<updated>2018-10-25T18:14:36Z</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2018-10-25T18:14:36Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=4dcb9239dad6cee17c538482619a5b659774ee51'/>
<id>urn:sha1:4dcb9239dad6cee17c538482619a5b659774ee51</id>
<content type='text'>
Pull timekeeping updates from Thomas Gleixner:
 "The timers and timekeeping departement provides:

   - Another large y2038 update with further preparations for providing
     the y2038 safe timespecs closer to the syscalls.

   - An overhaul of the SHCMT clocksource driver

   - SPDX license identifier updates

   - Small cleanups and fixes all over the place"

* 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (31 commits)
  tick/sched : Remove redundant cpu_online() check
  clocksource/drivers/dw_apb: Add reset control
  clocksource: Remove obsolete CLOCKSOURCE_OF_DECLARE
  clocksource/drivers: Unify the names to timer-* format
  clocksource/drivers/sh_cmt: Add R-Car gen3 support
  dt-bindings: timer: renesas: cmt: document R-Car gen3 support
  clocksource/drivers/sh_cmt: Properly line-wrap sh_cmt_of_table[] initializer
  clocksource/drivers/sh_cmt: Fix clocksource width for 32-bit machines
  clocksource/drivers/sh_cmt: Fixup for 64-bit machines
  clocksource/drivers/sh_tmu: Convert to SPDX identifiers
  clocksource/drivers/sh_mtu2: Convert to SPDX identifiers
  clocksource/drivers/sh_cmt: Convert to SPDX identifiers
  clocksource/drivers/renesas-ostm: Convert to SPDX identifiers
  clocksource: Convert to using %pOFn instead of device_node.name
  tick/broadcast: Remove redundant check
  RISC-V: Request newstat syscalls
  y2038: signal: Change rt_sigtimedwait to use __kernel_timespec
  y2038: socket: Change recvmmsg to use __kernel_timespec
  y2038: sched: Change sched_rr_get_interval to use __kernel_timespec
  y2038: utimes: Rework #ifdef guards for compat syscalls
  ...
</content>
</entry>
<entry>
<title>Merge branch 'siginfo-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace</title>
<updated>2018-10-24T10:22:39Z</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2018-10-24T10:22:39Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=ba9f6f8954afa5224e3ed60332f7b92242b7ed0f'/>
<id>urn:sha1:ba9f6f8954afa5224e3ed60332f7b92242b7ed0f</id>
<content type='text'>
Pull siginfo updates from Eric Biederman:
 "I have been slowly sorting out siginfo and this is the culmination of
  that work.

  The primary result is in several ways the signal infrastructure has
  been made less error prone. The code has been updated so that manually
  specifying SEND_SIG_FORCED is never necessary. The conversion to the
  new siginfo sending functions is now complete, which makes it
  difficult to send a signal without filling in the proper siginfo
  fields.

  At the tail end of the patchset comes the optimization of decreasing
  the size of struct siginfo in the kernel from 128 bytes to about 48
  bytes on 64bit. The fundamental observation that enables this is by
  definition none of the known ways to use struct siginfo uses the extra
  bytes.

  This comes at the cost of a small user space observable difference.
  For the rare case of siginfo being injected into the kernel only what
  can be copied into kernel_siginfo is delivered to the destination, the
  rest of the bytes are set to 0. For cases where the signal and the
  si_code are known this is safe, because we know those bytes are not
  used. For cases where the signal and si_code combination is unknown
  the bits that won't fit into struct kernel_siginfo are tested to
  verify they are zero, and the send fails if they are not.

  I made an extensive search through userspace code and I could not find
  anything that would break because of the above change. If it turns out
  I did break something it will take just the revert of a single change
  to restore kernel_siginfo to the same size as userspace siginfo.

  Testing did reveal dependencies on preferring the signo passed to
  sigqueueinfo over si-&gt;signo, so bit the bullet and added the
  complexity necessary to handle that case.

  Testing also revealed bad things can happen if a negative signal
  number is passed into the system calls. Something no sane application
  will do but something a malicious program or a fuzzer might do. So I
  have fixed the code that performs the bounds checks to ensure negative
  signal numbers are handled"

* 'siginfo-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace: (80 commits)
  signal: Guard against negative signal numbers in copy_siginfo_from_user32
  signal: Guard against negative signal numbers in copy_siginfo_from_user
  signal: In sigqueueinfo prefer sig not si_signo
  signal: Use a smaller struct siginfo in the kernel
  signal: Distinguish between kernel_siginfo and siginfo
  signal: Introduce copy_siginfo_from_user and use it's return value
  signal: Remove the need for __ARCH_SI_PREABLE_SIZE and SI_PAD_SIZE
  signal: Fail sigqueueinfo if si_signo != sig
  signal/sparc: Move EMT_TAGOVF into the generic siginfo.h
  signal/unicore32: Use force_sig_fault where appropriate
  signal/unicore32: Generate siginfo in ucs32_notify_die
  signal/unicore32: Use send_sig_fault where appropriate
  signal/arc: Use force_sig_fault where appropriate
  signal/arc: Push siginfo generation into unhandled_exception
  signal/ia64: Use force_sig_fault where appropriate
  signal/ia64: Use the force_sig(SIGSEGV,...) in ia64_rt_sigreturn
  signal/ia64: Use the generic force_sigsegv in setup_frame
  signal/arm/kvm: Use send_sig_mceerr
  signal/arm: Use send_sig_fault where appropriate
  signal/arm: Use force_sig_fault where appropriate
  ...
</content>
</entry>
<entry>
<title>signal: Distinguish between kernel_siginfo and siginfo</title>
<updated>2018-10-03T14:47:43Z</updated>
<author>
<name>Eric W. Biederman</name>
<email>ebiederm@xmission.com</email>
</author>
<published>2018-09-25T09:27:20Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=ae7795bc6187a15ec51cf258abae656a625f9980'/>
<id>urn:sha1:ae7795bc6187a15ec51cf258abae656a625f9980</id>
<content type='text'>
Linus recently observed that if we did not worry about the padding
member in struct siginfo it is only about 48 bytes, and 48 bytes is
much nicer than 128 bytes for allocating on the stack and copying
around in the kernel.

The obvious thing of only adding the padding when userspace is
including siginfo.h won't work as there are sigframe definitions in
the kernel that embed struct siginfo.

So split siginfo in two; kernel_siginfo and siginfo.  Keeping the
traditional name for the userspace definition.  While the version that
is used internally to the kernel and ultimately will not be padded to
128 bytes is called kernel_siginfo.

The definition of struct kernel_siginfo I have put in include/signal_types.h

A set of buildtime checks has been added to verify the two structures have
the same field offsets.

To make it easy to verify the change kernel_siginfo retains the same
size as siginfo.  The reduction in size comes in a following change.

Signed-off-by: "Eric W. Biederman" &lt;ebiederm@xmission.com&gt;
</content>
</entry>
<entry>
<title>signal: Introduce COMPAT_SIGMINSTKSZ for use in compat_sys_sigaltstack</title>
<updated>2018-10-01T10:43:55Z</updated>
<author>
<name>Will Deacon</name>
<email>will.deacon@arm.com</email>
</author>
<published>2018-09-05T14:34:42Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=22839869f21ab3850fbbac9b425ccc4c0023926f'/>
<id>urn:sha1:22839869f21ab3850fbbac9b425ccc4c0023926f</id>
<content type='text'>
The sigaltstack(2) system call fails with -ENOMEM if the new alternative
signal stack is found to be smaller than SIGMINSTKSZ. On architectures
such as arm64, where the native value for SIGMINSTKSZ is larger than
the compat value, this can result in an unexpected error being reported
to a compat task. See, for example:

  https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=904385

This patch fixes the problem by extending do_sigaltstack to take the
minimum signal stack size as an additional parameter, allowing the
native and compat system call entry code to pass in their respective
values. COMPAT_SIGMINSTKSZ is just defined as SIGMINSTKSZ if it has not
been defined by the architecture.

Cc: Arnd Bergmann &lt;arnd@arndb.de&gt;
Cc: Dominik Brodowski &lt;linux@dominikbrodowski.net&gt;
Cc: "Eric W. Biederman" &lt;ebiederm@xmission.com&gt;
Cc: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Cc: Al Viro &lt;viro@zeniv.linux.org.uk&gt;
Cc: Oleg Nesterov &lt;oleg@redhat.com&gt;
Reported-by: Steve McIntyre &lt;steve.mcintyre@arm.com&gt;
Tested-by: Steve McIntyre &lt;93sam@debian.org&gt;
Signed-off-by: Will Deacon &lt;will.deacon@arm.com&gt;
Signed-off-by: Catalin Marinas &lt;catalin.marinas@arm.com&gt;
</content>
</entry>
<entry>
<title>y2038: utimes: Rework #ifdef guards for compat syscalls</title>
<updated>2018-08-29T13:42:23Z</updated>
<author>
<name>Arnd Bergmann</name>
<email>arnd@arndb.de</email>
</author>
<published>2018-04-17T10:03:19Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=4faea239e529d1d6b3b93fbf08d5e90427961a41'/>
<id>urn:sha1:4faea239e529d1d6b3b93fbf08d5e90427961a41</id>
<content type='text'>
After changing over to 64-bit time_t syscalls, many architectures will
want compat_sys_utimensat() but not respective handlers for utime(),
utimes() and futimesat(). This adds a new __ARCH_WANT_SYS_UTIME32 to
complement __ARCH_WANT_SYS_UTIME. For now, all 64-bit architectures that
support CONFIG_COMPAT set it, but future 64-bit architectures will not
(tile would not have needed it either, but got removed).

As older 32-bit architectures get converted to using CONFIG_64BIT_TIME,
they will have to use __ARCH_WANT_SYS_UTIME32 instead of
__ARCH_WANT_SYS_UTIME. Architectures using the generic syscall ABI don't
need either of them as they never had a utime syscall.

Since the compat_utimbuf structure is now required outside of
CONFIG_COMPAT, I'm moving it into compat_time.h.

Signed-off-by: Arnd Bergmann &lt;arnd@arndb.de&gt;
---
changed from last version:
- renamed __ARCH_WANT_COMPAT_SYS_UTIME to __ARCH_WANT_SYS_UTIME32
</content>
</entry>
<entry>
<title>asm-generic: Move common compat types to asm-generic/compat.h</title>
<updated>2018-08-29T13:42:20Z</updated>
<author>
<name>Arnd Bergmann</name>
<email>arnd@arndb.de</email>
</author>
<published>2018-04-18T20:01:26Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=fb3739759474d150a9927b920a80ea2afb4c2a51'/>
<id>urn:sha1:fb3739759474d150a9927b920a80ea2afb4c2a51</id>
<content type='text'>
While converting compat system call handlers to work on 32-bit
architectures, I found a number of types used in those handlers
that are identical between all architectures.

Let's move all the identical ones into asm-generic/compat.h to avoid
having to add even more identical definitions of those types.

For unknown reasons, mips defines __compat_gid32_t, __compat_uid32_t
and compat_caddr_t as signed, while all others have them unsigned.
This seems to be a mistake, but I'm leaving it alone here. The other
types all differ by size or alignment on at least on architecture.

compat_aio_context_t is currently defined in linux/compat.h but
also needed for compat_sys_io_getevents(), so let's move it into
the same place.

While we still have not decided whether the 32-bit time handling
will always use the compat syscalls, or in which form, I think this
is a useful cleanup that we can merge regardless.

Reviewed-by: Christoph Hellwig &lt;hch@lst.de&gt;
Signed-off-by: Arnd Bergmann &lt;arnd@arndb.de&gt;
</content>
</entry>
<entry>
<title>y2038: globally rename compat_time to old_time32</title>
<updated>2018-08-27T12:48:48Z</updated>
<author>
<name>Arnd Bergmann</name>
<email>arnd@arndb.de</email>
</author>
<published>2018-07-13T10:52:28Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=9afc5eee65ca7d717a99d6fe8f4adfe32a40940a'/>
<id>urn:sha1:9afc5eee65ca7d717a99d6fe8f4adfe32a40940a</id>
<content type='text'>
Christoph Hellwig suggested a slightly different path for handling
backwards compatibility with the 32-bit time_t based system calls:

Rather than simply reusing the compat_sys_* entry points on 32-bit
architectures unchanged, we get rid of those entry points and the
compat_time types by renaming them to something that makes more sense
on 32-bit architectures (which don't have a compat mode otherwise),
and then share the entry points under the new name with the 64-bit
architectures that use them for implementing the compatibility.

The following types and interfaces are renamed here, and moved
from linux/compat_time.h to linux/time32.h:

old				new
---				---
compat_time_t			old_time32_t
struct compat_timeval		struct old_timeval32
struct compat_timespec		struct old_timespec32
struct compat_itimerspec	struct old_itimerspec32
ns_to_compat_timeval()		ns_to_old_timeval32()
get_compat_itimerspec64()	get_old_itimerspec32()
put_compat_itimerspec64()	put_old_itimerspec32()
compat_get_timespec64()		get_old_timespec32()
compat_put_timespec64()		put_old_timespec32()

As we already have aliases in place, this patch addresses only the
instances that are relevant to the system call interface in particular,
not those that occur in device drivers and other modules. Those
will get handled separately, while providing the 64-bit version
of the respective interfaces.

I'm not renaming the timex, rusage and itimerval structures, as we are
still debating what the new interface will look like, and whether we
will need a replacement at all.

This also doesn't change the names of the syscall entry points, which can
be done more easily when we actually switch over the 32-bit architectures
to use them, at that point we need to change COMPAT_SYSCALL_DEFINEx to
SYSCALL_DEFINEx with a new name, e.g. with a _time32 suffix.

Suggested-by: Christoph Hellwig &lt;hch@infradead.org&gt;
Link: https://lore.kernel.org/lkml/20180705222110.GA5698@infradead.org/
Signed-off-by: Arnd Bergmann &lt;arnd@arndb.de&gt;
</content>
</entry>
</feed>
