<feed xmlns='http://www.w3.org/2005/Atom'>
<title>user/sven/linux.git/scripts, branch v4.19.54</title>
<subtitle>Linux Kernel
</subtitle>
<id>https://git.stealer.net/cgit.cgi/user/sven/linux.git/atom?h=v4.19.54</id>
<link rel='self' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/atom?h=v4.19.54'/>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/'/>
<updated>2019-06-09T07:17:22Z</updated>
<entry>
<title>gcc-plugins: Fix build failures under Darwin host</title>
<updated>2019-06-09T07:17:22Z</updated>
<author>
<name>Kees Cook</name>
<email>keescook@chromium.org</email>
</author>
<published>2019-05-20T18:50:42Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=132137d1bfa16d6b127d7b3761c07540ea42a529'/>
<id>urn:sha1:132137d1bfa16d6b127d7b3761c07540ea42a529</id>
<content type='text'>
commit 7210e060155b9cf557fb13128353c3e494fa5ed3 upstream.

The gcc-common.h file did not take into account certain macros that
might have already been defined in the build environment. This updates
the header to avoid redefining the macros, as seen on a Darwin host
using gcc 4.9.2:

 HOSTCXX -fPIC scripts/gcc-plugins/arm_ssp_per_task_plugin.o - due to: scripts/gcc-plugins/gcc-common.h
In file included from scripts/gcc-plugins/arm_ssp_per_task_plugin.c:3:0:
scripts/gcc-plugins/gcc-common.h:153:0: warning: "__unused" redefined
^
In file included from /usr/include/stdio.h:64:0,
                from /Users/hns/Documents/Projects/QuantumSTEP/System/Library/Frameworks/System.framework/Versions-jessie/x86_64-apple-darwin15.0.0/gcc/arm-linux-gnueabi/bin/../lib/gcc/arm-linux-gnueabi/4.9.2/plugin/include/system.h:40,
                from /Users/hns/Documents/Projects/QuantumSTEP/System/Library/Frameworks/System.framework/Versions-jessie/x86_64-apple-darwin15.0.0/gcc/arm-linux-gnueabi/bin/../lib/gcc/arm-linux-gnueabi/4.9.2/plugin/include/gcc-plugin.h:28,
                from /Users/hns/Documents/Projects/QuantumSTEP/System/Library/Frameworks/System.framework/Versions-jessie/x86_64-apple-darwin15.0.0/gcc/arm-linux-gnueabi/bin/../lib/gcc/arm-linux-gnueabi/4.9.2/plugin/include/plugin.h:23,
                from scripts/gcc-plugins/gcc-common.h:9,
                from scripts/gcc-plugins/arm_ssp_per_task_plugin.c:3:
/usr/include/sys/cdefs.h:161:0: note: this is the location of the previous definition
^

Reported-and-tested-by: "H. Nikolaus Schaller" &lt;hns@goldelico.com&gt;
Fixes: 189af4657186 ("ARM: smp: add support for per-task stack canaries")
Cc: stable@vger.kernel.org
Signed-off-by: Kees Cook &lt;keescook@chromium.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</content>
</entry>
<entry>
<title>jump_label: move 'asm goto' support test to Kconfig</title>
<updated>2019-06-04T06:02:34Z</updated>
<author>
<name>Masahiro Yamada</name>
<email>yamada.masahiro@socionext.com</email>
</author>
<published>2018-12-30T15:14:15Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=0276ebf16675f3745d8b6f384dcf917e1379eda2'/>
<id>urn:sha1:0276ebf16675f3745d8b6f384dcf917e1379eda2</id>
<content type='text'>
commit e9666d10a5677a494260d60d1fa0b73cc7646eb3 upstream.

Currently, CONFIG_JUMP_LABEL just means "I _want_ to use jump label".

The jump label is controlled by HAVE_JUMP_LABEL, which is defined
like this:

  #if defined(CC_HAVE_ASM_GOTO) &amp;&amp; defined(CONFIG_JUMP_LABEL)
  # define HAVE_JUMP_LABEL
  #endif

We can improve this by testing 'asm goto' support in Kconfig, then
make JUMP_LABEL depend on CC_HAS_ASM_GOTO.

Ugly #ifdef HAVE_JUMP_LABEL will go away, and CONFIG_JUMP_LABEL will
match to the real kernel capability.

Signed-off-by: Masahiro Yamada &lt;yamada.masahiro@socionext.com&gt;
Acked-by: Michael Ellerman &lt;mpe@ellerman.id.au&gt; (powerpc)
Tested-by: Sedat Dilek &lt;sedat.dilek@gmail.com&gt;
[nc: Fix trivial conflicts in 4.19
     arch/xtensa/kernel/jump_label.c doesn't exist yet
     Ensured CC_HAVE_ASM_GOTO and HAVE_JUMP_LABEL were sufficiently
     eliminated]
Signed-off-by: Nathan Chancellor &lt;natechancellor@gmail.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;


</content>
</entry>
<entry>
<title>fs: stream_open - opener for stream-like files so that read and write can run simultaneously without deadlock</title>
<updated>2019-05-08T05:21:51Z</updated>
<author>
<name>Kirill Smelkov</name>
<email>kirr@nexedi.com</email>
</author>
<published>2019-03-26T22:20:43Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=04b4d5f75ab04858a9b6dff94d74e4fdf0b9f194'/>
<id>urn:sha1:04b4d5f75ab04858a9b6dff94d74e4fdf0b9f194</id>
<content type='text'>
[ Upstream commit 10dce8af34226d90fa56746a934f8da5dcdba3df ]

Commit 9c225f2655e3 ("vfs: atomic f_pos accesses as per POSIX") added
locking for file.f_pos access and in particular made concurrent read and
write not possible - now both those functions take f_pos lock for the
whole run, and so if e.g. a read is blocked waiting for data, write will
deadlock waiting for that read to complete.

This caused regression for stream-like files where previously read and
write could run simultaneously, but after that patch could not do so
anymore. See e.g. commit 581d21a2d02a ("xenbus: fix deadlock on writes
to /proc/xen/xenbus") which fixes such regression for particular case of
/proc/xen/xenbus.

The patch that added f_pos lock in 2014 did so to guarantee POSIX thread
safety for read/write/lseek and added the locking to file descriptors of
all regular files. In 2014 that thread-safety problem was not new as it
was already discussed earlier in 2006.

However even though 2006'th version of Linus's patch was adding f_pos
locking "only for files that are marked seekable with FMODE_LSEEK (thus
avoiding the stream-like objects like pipes and sockets)", the 2014
version - the one that actually made it into the tree as 9c225f2655e3 -
is doing so irregardless of whether a file is seekable or not.

See

    https://lore.kernel.org/lkml/53022DB1.4070805@gmail.com/
    https://lwn.net/Articles/180387
    https://lwn.net/Articles/180396

for historic context.

The reason that it did so is, probably, that there are many files that
are marked non-seekable, but e.g. their read implementation actually
depends on knowing current position to correctly handle the read. Some
examples:

	kernel/power/user.c		snapshot_read
	fs/debugfs/file.c		u32_array_read
	fs/fuse/control.c		fuse_conn_waiting_read + ...
	drivers/hwmon/asus_atk0110.c	atk_debugfs_ggrp_read
	arch/s390/hypfs/inode.c		hypfs_read_iter
	...

Despite that, many nonseekable_open users implement read and write with
pure stream semantics - they don't depend on passed ppos at all. And for
those cases where read could wait for something inside, it creates a
situation similar to xenbus - the write could be never made to go until
read is done, and read is waiting for some, potentially external, event,
for potentially unbounded time -&gt; deadlock.

Besides xenbus, there are 14 such places in the kernel that I've found
with semantic patch (see below):

	drivers/xen/evtchn.c:667:8-24: ERROR: evtchn_fops: .read() can deadlock .write()
	drivers/isdn/capi/capi.c:963:8-24: ERROR: capi_fops: .read() can deadlock .write()
	drivers/input/evdev.c:527:1-17: ERROR: evdev_fops: .read() can deadlock .write()
	drivers/char/pcmcia/cm4000_cs.c:1685:7-23: ERROR: cm4000_fops: .read() can deadlock .write()
	net/rfkill/core.c:1146:8-24: ERROR: rfkill_fops: .read() can deadlock .write()
	drivers/s390/char/fs3270.c:488:1-17: ERROR: fs3270_fops: .read() can deadlock .write()
	drivers/usb/misc/ldusb.c:310:1-17: ERROR: ld_usb_fops: .read() can deadlock .write()
	drivers/hid/uhid.c:635:1-17: ERROR: uhid_fops: .read() can deadlock .write()
	net/batman-adv/icmp_socket.c:80:1-17: ERROR: batadv_fops: .read() can deadlock .write()
	drivers/media/rc/lirc_dev.c:198:1-17: ERROR: lirc_fops: .read() can deadlock .write()
	drivers/leds/uleds.c:77:1-17: ERROR: uleds_fops: .read() can deadlock .write()
	drivers/input/misc/uinput.c:400:1-17: ERROR: uinput_fops: .read() can deadlock .write()
	drivers/infiniband/core/user_mad.c:985:7-23: ERROR: umad_fops: .read() can deadlock .write()
	drivers/gnss/core.c:45:1-17: ERROR: gnss_fops: .read() can deadlock .write()

In addition to the cases above another regression caused by f_pos
locking is that now FUSE filesystems that implement open with
FOPEN_NONSEEKABLE flag, can no longer implement bidirectional
stream-like files - for the same reason as above e.g. read can deadlock
write locking on file.f_pos in the kernel.

FUSE's FOPEN_NONSEEKABLE was added in 2008 in a7c1b990f715 ("fuse:
implement nonseekable open") to support OSSPD. OSSPD implements /dev/dsp
in userspace with FOPEN_NONSEEKABLE flag, with corresponding read and
write routines not depending on current position at all, and with both
read and write being potentially blocking operations:

See

    https://github.com/libfuse/osspd
    https://lwn.net/Articles/308445

    https://github.com/libfuse/osspd/blob/14a9cff0/osspd.c#L1406
    https://github.com/libfuse/osspd/blob/14a9cff0/osspd.c#L1438-L1477
    https://github.com/libfuse/osspd/blob/14a9cff0/osspd.c#L1479-L1510

Corresponding libfuse example/test also describes FOPEN_NONSEEKABLE as
"somewhat pipe-like files ..." with read handler not using offset.
However that test implements only read without write and cannot exercise
the deadlock scenario:

    https://github.com/libfuse/libfuse/blob/fuse-3.4.2-3-ga1bff7d/example/poll.c#L124-L131
    https://github.com/libfuse/libfuse/blob/fuse-3.4.2-3-ga1bff7d/example/poll.c#L146-L163
    https://github.com/libfuse/libfuse/blob/fuse-3.4.2-3-ga1bff7d/example/poll.c#L209-L216

I've actually hit the read vs write deadlock for real while implementing
my FUSE filesystem where there is /head/watch file, for which open
creates separate bidirectional socket-like stream in between filesystem
and its user with both read and write being later performed
simultaneously. And there it is semantically not easy to split the
stream into two separate read-only and write-only channels:

    https://lab.nexedi.com/kirr/wendelin.core/blob/f13aa600/wcfs/wcfs.go#L88-169

Let's fix this regression. The plan is:

1. We can't change nonseekable_open to include &amp;~FMODE_ATOMIC_POS -
   doing so would break many in-kernel nonseekable_open users which
   actually use ppos in read/write handlers.

2. Add stream_open() to kernel to open stream-like non-seekable file
   descriptors. Read and write on such file descriptors would never use
   nor change ppos. And with that property on stream-like files read and
   write will be running without taking f_pos lock - i.e. read and write
   could be running simultaneously.

3. With semantic patch search and convert to stream_open all in-kernel
   nonseekable_open users for which read and write actually do not
   depend on ppos and where there is no other methods in file_operations
   which assume @offset access.

4. Add FOPEN_STREAM to fs/fuse/ and open in-kernel file-descriptors via
   steam_open if that bit is present in filesystem open reply.

   It was tempting to change fs/fuse/ open handler to use stream_open
   instead of nonseekable_open on just FOPEN_NONSEEKABLE flags, but
   grepping through Debian codesearch shows users of FOPEN_NONSEEKABLE,
   and in particular GVFS which actually uses offset in its read and
   write handlers

	https://codesearch.debian.net/search?q=-%3Enonseekable+%3D
	https://gitlab.gnome.org/GNOME/gvfs/blob/1.40.0-6-gcbc54396/client/gvfsfusedaemon.c#L1080
	https://gitlab.gnome.org/GNOME/gvfs/blob/1.40.0-6-gcbc54396/client/gvfsfusedaemon.c#L1247-1346
	https://gitlab.gnome.org/GNOME/gvfs/blob/1.40.0-6-gcbc54396/client/gvfsfusedaemon.c#L1399-1481

   so if we would do such a change it will break a real user.

5. Add stream_open and FOPEN_STREAM handling to stable kernels starting
   from v3.14+ (the kernel where 9c225f2655 first appeared).

   This will allow to patch OSSPD and other FUSE filesystems that
   provide stream-like files to return FOPEN_STREAM | FOPEN_NONSEEKABLE
   in their open handler and this way avoid the deadlock on all kernel
   versions. This should work because fs/fuse/ ignores unknown open
   flags returned from a filesystem and so passing FOPEN_STREAM to a
   kernel that is not aware of this flag cannot hurt. In turn the kernel
   that is not aware of FOPEN_STREAM will be &lt; v3.14 where just
   FOPEN_NONSEEKABLE is sufficient to implement streams without read vs
   write deadlock.

This patch adds stream_open, converts /proc/xen/xenbus to it and adds
semantic patch to automatically locate in-kernel places that are either
required to be converted due to read vs write deadlock, or that are just
safe to be converted because read and write do not use ppos and there
are no other funky methods in file_operations.

Regarding semantic patch I've verified each generated change manually -
that it is correct to convert - and each other nonseekable_open instance
left - that it is either not correct to convert there, or that it is not
converted due to current stream_open.cocci limitations.

The script also does not convert files that should be valid to convert,
but that currently have .llseek = noop_llseek or generic_file_llseek for
unknown reason despite file being opened with nonseekable_open (e.g.
drivers/input/mousedev.c)

Cc: Michael Kerrisk &lt;mtk.manpages@gmail.com&gt;
Cc: Yongzhi Pan &lt;panyongzhi@gmail.com&gt;
Cc: Jonathan Corbet &lt;corbet@lwn.net&gt;
Cc: David Vrabel &lt;david.vrabel@citrix.com&gt;
Cc: Juergen Gross &lt;jgross@suse.com&gt;
Cc: Miklos Szeredi &lt;miklos@szeredi.hu&gt;
Cc: Tejun Heo &lt;tj@kernel.org&gt;
Cc: Kirill Tkhai &lt;ktkhai@virtuozzo.com&gt;
Cc: Arnd Bergmann &lt;arnd@arndb.de&gt;
Cc: Christoph Hellwig &lt;hch@lst.de&gt;
Cc: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
Cc: Julia Lawall &lt;Julia.Lawall@lip6.fr&gt;
Cc: Nikolaus Rath &lt;Nikolaus@rath.org&gt;
Cc: Han-Wen Nienhuys &lt;hanwen@google.com&gt;
Signed-off-by: Kirill Smelkov &lt;kirr@nexedi.com&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
</entry>
<entry>
<title>kconfig/[mn]conf: handle backspace (^H) key</title>
<updated>2019-05-04T07:20:22Z</updated>
<author>
<name>Changbin Du</name>
<email>changbin.du@gmail.com</email>
</author>
<published>2019-03-25T15:16:47Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=75a5e3e6340cc07c1f87dcd7b82596a308c7e9fb'/>
<id>urn:sha1:75a5e3e6340cc07c1f87dcd7b82596a308c7e9fb</id>
<content type='text'>
[ Upstream commit 9c38f1f044080392603c497ecca4d7d09876ff99 ]

Backspace is not working on some terminal emulators which do not send the
key code defined by terminfo. Terminals either send '^H' (8) or '^?' (127).
But currently only '^?' is handled. Let's also handle '^H' for those
terminals.

Signed-off-by: Changbin Du &lt;changbin.du@gmail.com&gt;
Signed-off-by: Masahiro Yamada &lt;yamada.masahiro@socionext.com&gt;
Signed-off-by: Sasha Levin (Microsoft) &lt;sashal@kernel.org&gt;
</content>
</entry>
<entry>
<title>selinux: use kernel linux/socket.h for genheaders and mdp</title>
<updated>2019-05-04T07:20:10Z</updated>
<author>
<name>Paulo Alcantara</name>
<email>paulo@paulo.ac</email>
</author>
<published>2019-02-25T00:55:28Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=145f6a70bb9b422a6df5fb8b9408046151f3e4f9'/>
<id>urn:sha1:145f6a70bb9b422a6df5fb8b9408046151f3e4f9</id>
<content type='text'>
commit dfbd199a7cfe3e3cd8531e1353cdbd7175bfbc5e upstream.

When compiling genheaders and mdp from a newer host kernel, the
following error happens:

    In file included from scripts/selinux/genheaders/genheaders.c:18:
    ./security/selinux/include/classmap.h:238:2: error: #error New
    address family defined, please update secclass_map.  #error New
    address family defined, please update secclass_map.  ^~~~~
    make[3]: *** [scripts/Makefile.host:107:
    scripts/selinux/genheaders/genheaders] Error 1 make[2]: ***
    [scripts/Makefile.build:599: scripts/selinux/genheaders] Error 2
    make[1]: *** [scripts/Makefile.build:599: scripts/selinux] Error 2
    make[1]: *** Waiting for unfinished jobs....

Instead of relying on the host definition, include linux/socket.h in
classmap.h to have PF_MAX.

Cc: stable@vger.kernel.org
Signed-off-by: Paulo Alcantara &lt;paulo@paulo.ac&gt;
Acked-by: Stephen Smalley &lt;sds@tycho.nsa.gov&gt;
[PM: manually merge in mdp.c, subject line tweaks]
Signed-off-by: Paul Moore &lt;paul@paul-moore.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</content>
</entry>
<entry>
<title>modpost: file2alias: check prototype of handler</title>
<updated>2019-04-27T07:36:39Z</updated>
<author>
<name>Masahiro Yamada</name>
<email>yamada.masahiro@socionext.com</email>
</author>
<published>2018-11-22T04:28:42Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=7de43cb71116ab13adaf1f57a72edb6757ca57d0'/>
<id>urn:sha1:7de43cb71116ab13adaf1f57a72edb6757ca57d0</id>
<content type='text'>
[ Upstream commit f880eea68fe593342fa6e09be9bb661f3c297aec ]

Use specific prototype instead of an opaque pointer so that the
compiler can catch function prototype mismatch.

Signed-off-by: Masahiro Yamada &lt;yamada.masahiro@socionext.com&gt;
Reviewed-by: Mathieu Malaterre &lt;malat@debian.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
</entry>
<entry>
<title>modpost: file2alias: go back to simple devtable lookup</title>
<updated>2019-04-27T07:36:39Z</updated>
<author>
<name>Masahiro Yamada</name>
<email>yamada.masahiro@socionext.com</email>
</author>
<published>2018-11-22T04:28:41Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=aa0e8cc9d7a89bb0c23435ec1b62eac46b1f4984'/>
<id>urn:sha1:aa0e8cc9d7a89bb0c23435ec1b62eac46b1f4984</id>
<content type='text'>
[ Upstream commit ec91e78d378cc5d4b43805a1227d8e04e5dfa17d ]

Commit e49ce14150c6 ("modpost: use linker section to generate table.")
was not so cool as we had expected first; it ended up with ugly section
hacks when commit dd2a3acaecd7 ("mod/file2alias: make modpost compile
on darwin again") came in.

Given a certain degree of unknowledge about the link stage of host
programs, I really want to see simple, stupid table lookup so that
this works in the same way regardless of the underlying executable
format.

Signed-off-by: Masahiro Yamada &lt;yamada.masahiro@socionext.com&gt;
Acked-by: Mathieu Malaterre &lt;malat@debian.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
</entry>
<entry>
<title>kbuild: deb-pkg: fix bindeb-pkg breakage when O= is used</title>
<updated>2019-04-17T06:38:45Z</updated>
<author>
<name>Masahiro Yamada</name>
<email>yamada.masahiro@socionext.com</email>
</author>
<published>2018-11-05T07:52:34Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=23605a4664ae8658ddbbbac4f75c404eb7e4715d'/>
<id>urn:sha1:23605a4664ae8658ddbbbac4f75c404eb7e4715d</id>
<content type='text'>
[ Upstream commit 02826a6ba301b72461c3706e1cc66d5571cd327e ]

Ard Biesheuvel reports bindeb-pkg with O= option is broken in the
following way:

  ...
    LD [M]  sound/soc/rockchip/snd-soc-rk3399-gru-sound.ko
    LD [M]  sound/soc/rockchip/snd-soc-rockchip-pcm.ko
    LD [M]  sound/soc/rockchip/snd-soc-rockchip-rt5645.ko
    LD [M]  sound/soc/rockchip/snd-soc-rockchip-spdif.ko
    LD [M]  sound/soc/sh/rcar/snd-soc-rcar.ko
   fakeroot -u debian/rules binary
  make KERNELRELEASE=4.19.0-12677-g19beffaf7a99-dirty ARCH=arm64 KBUILD_SRC= intdeb-pkg
  /bin/bash /home/ard/linux/scripts/package/builddeb
  Makefile:600: include/config/auto.conf: No such file or directory
  ***
  *** Configuration file ".config" not found!
  ***
  *** Please run some configurator (e.g. "make oldconfig" or
  *** "make menuconfig" or "make xconfig").
  ***
  make[12]: *** [syncconfig] Error 1
  make[11]: *** [syncconfig] Error 2
  make[10]: *** [include/config/auto.conf] Error 2
  make[9]: *** [__sub-make] Error 2
  ...

Prior to commit 80463f1b7bf9 ("kbuild: add --include-dir flag only
for out-of-tree build"), both srctree and objtree were added to
--include-dir redundantly, and the wrong code '$MAKE image_name'
was working by relying on that. Now, the potential issue that had
previously been hidden just showed up.

'$MAKE image_name' recurses to the generated $(objtree)/Makefile and
ends up with running in srctree, which is incorrect. It should be
invoked with '-f $srctree/Makefile' (or KBUILD_SRC=) to be executed
in objtree.

Fixes: 80463f1b7bf9 ("kbuild: add --include-dir flag only for out-of-tree build")
Reported-by: Ard Biesheuvel &lt;ard.biesheuvel@linaro.org&gt;
Signed-off-by: Masahiro Yamada &lt;yamada.masahiro@socionext.com&gt;
Tested-by: Ard Biesheuvel &lt;ard.biesheuvel@linaro.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
</entry>
<entry>
<title>kbuild: modversions: Fix relative CRC byte order interpretation</title>
<updated>2019-04-03T04:26:23Z</updated>
<author>
<name>Fredrik Noring</name>
<email>noring@nocrew.org</email>
</author>
<published>2019-03-27T18:12:50Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=aa7f29f870278fca449a26e990717a46ec93834a'/>
<id>urn:sha1:aa7f29f870278fca449a26e990717a46ec93834a</id>
<content type='text'>
commit 54a7151b1496cddbb7a83546b7998103e98edc88 upstream.

Fix commit 56067812d5b0 ("kbuild: modversions: add infrastructure for
emitting relative CRCs") where CRCs are interpreted in host byte order
rather than proper kernel byte order. The bug is conditional on
CONFIG_MODULE_REL_CRCS.

For example, when loading a BE module into a BE kernel compiled with a LE
system, the error "disagrees about version of symbol module_layout" is
produced. A message such as "Found checksum D7FA6856 vs module 5668FAD7"
will be given with debug enabled, which indicates an obvious endian
problem within __kcrctab within the kernel image.

The general solution is to use the macro TO_NATIVE, as is done in
similar cases throughout modpost.c. With this correction it has been
verified that a BE kernel compiled with a LE system accepts BE modules.

This change has also been verified with a LE kernel compiled with a LE
system, in which case TO_NATIVE returns its value unmodified since the
byte orders match. This is by far the common case.

Fixes: 56067812d5b0 ("kbuild: modversions: add infrastructure for emitting relative CRCs")
Signed-off-by: Fredrik Noring &lt;noring@nocrew.org&gt;
Cc: stable@vger.kernel.org
Signed-off-by: Masahiro Yamada &lt;yamada.masahiro@socionext.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</content>
</entry>
<entry>
<title>kallsyms: Handle too long symbols in kallsyms.c</title>
<updated>2019-03-23T19:09:47Z</updated>
<author>
<name>Eugene Loh</name>
<email>eugene.loh@oracle.com</email>
</author>
<published>2019-01-17T22:46:00Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=cacf3c0d82889b7628e98952bf1207aff398389a'/>
<id>urn:sha1:cacf3c0d82889b7628e98952bf1207aff398389a</id>
<content type='text'>
[ Upstream commit 6db2983cd8064808141ccefd75218f5b4345ffae ]

When checking for symbols with excessively long names,
account for null terminating character.

Fixes: f3462aa952cf ("Kbuild: Handle longer symbols in kallsyms.c")
Signed-off-by: Eugene Loh &lt;eugene.loh@oracle.com&gt;
Acked-by: Ard Biesheuvel &lt;ard.biesheuvel@linaro.org&gt;
Signed-off-by: Masahiro Yamada &lt;yamada.masahiro@socionext.com&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
</entry>
</feed>
