Commit graph

4136 commits

Author SHA1 Message Date
Vasily Gorbik
32797c9105 kallsyms: exclude kasan local symbols on s390
[ Upstream commit 33177f01ca ]

gcc asan instrumentation emits the following sequence to store frame pc
when the kernel is built with CONFIG_RELOCATABLE:
debug/vsprintf.s:
        .section        .data.rel.ro.local,"aw"
        .align  8
.LC3:
        .quad   .LASANPC4826@GOTOFF
.text
        .align  8
        .type   number, @function
number:
.LASANPC4826:

and in case reloc is issued for LASANPC label it also gets into .symtab
with the same address as actual function symbol:
$ nm -n vmlinux | grep 0000000001397150
0000000001397150 t .LASANPC4826
0000000001397150 t number

In the end kernel backtraces are almost unreadable:
[  143.748476] Call Trace:
[  143.748484] ([<000000002da3e62c>] .LASANPC2671+0x114/0x190)
[  143.748492]  [<000000002eca1a58>] .LASANPC2612+0x110/0x160
[  143.748502]  [<000000002de9d830>] print_address_description+0x80/0x3b0
[  143.748511]  [<000000002de9dd64>] __kasan_report+0x15c/0x1c8
[  143.748521]  [<000000002ecb56d4>] strrchr+0x34/0x60
[  143.748534]  [<000003ff800a9a40>] kasan_strings+0xb0/0x148 [test_kasan]
[  143.748547]  [<000003ff800a9bba>] kmalloc_tests_init+0xe2/0x528 [test_kasan]
[  143.748555]  [<000000002da2117c>] .LASANPC4069+0x354/0x748
[  143.748563]  [<000000002dbfbb16>] do_init_module+0x136/0x3b0
[  143.748571]  [<000000002dbff3f4>] .LASANPC3191+0x2164/0x25d0
[  143.748580]  [<000000002dbffc4c>] .LASANPC3196+0x184/0x1b8
[  143.748587]  [<000000002ecdf2ec>] system_call+0xd8/0x2d8

Since LASANPC labels are not even unique and get into .symtab only due
to relocs filter them out in kallsyms.

Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-07-31 07:28:54 +02:00
Naveen N. Rao
dab80aa013 recordmcount: Fix spurious mcount entries on powerpc
[ Upstream commit 80e5302e4b ]

An impending change to enable HAVE_C_RECORDMCOUNT on powerpc leads to
warnings such as the following:

  # modprobe kprobe_example
  ftrace-powerpc: Not expected bl: opcode is 3c4c0001
  WARNING: CPU: 0 PID: 227 at kernel/trace/ftrace.c:2001 ftrace_bug+0x90/0x318
  Modules linked in:
  CPU: 0 PID: 227 Comm: modprobe Not tainted 5.2.0-rc6-00678-g1c329100b942 #2
  NIP:  c000000000264318 LR: c00000000025d694 CTR: c000000000f5cd30
  REGS: c000000001f2b7b0 TRAP: 0700   Not tainted  (5.2.0-rc6-00678-g1c329100b942)
  MSR:  900000010282b033 <SF,HV,VEC,VSX,EE,FP,ME,IR,DR,RI,LE,TM[E]>  CR: 28228222  XER: 00000000
  CFAR: c0000000002642fc IRQMASK: 0
  <snip>
  NIP [c000000000264318] ftrace_bug+0x90/0x318
  LR [c00000000025d694] ftrace_process_locs+0x4f4/0x5e0
  Call Trace:
  [c000000001f2ba40] [0000000000000004] 0x4 (unreliable)
  [c000000001f2bad0] [c00000000025d694] ftrace_process_locs+0x4f4/0x5e0
  [c000000001f2bb90] [c00000000020ff10] load_module+0x25b0/0x30c0
  [c000000001f2bd00] [c000000000210cb0] sys_finit_module+0xc0/0x130
  [c000000001f2be20] [c00000000000bda4] system_call+0x5c/0x70
  Instruction dump:
  419e0018 2f83ffff 419e00bc 2f83ffea 409e00cc 4800001c 0fe00000 3c62ff96
  39000001 39400000 386386d0 480000c4 <0fe00000> 3ce20003 39000001 3c62ff96
  ---[ end trace 4c438d5cebf78381 ]---
  ftrace failed to modify
  [<c0080000012a0008>] 0xc0080000012a0008
   actual:   01:00:4c:3c
  Initializing ftrace call sites
  ftrace record flags: 2000000
   (0)
   expected tramp: c00000000006af4c

Looking at the relocation records in __mcount_loc shows a few spurious
entries:

  RELOCATION RECORDS FOR [__mcount_loc]:
  OFFSET           TYPE              VALUE
  0000000000000000 R_PPC64_ADDR64    .text.unlikely+0x0000000000000008
  0000000000000008 R_PPC64_ADDR64    .text.unlikely+0x0000000000000014
  0000000000000010 R_PPC64_ADDR64    .text.unlikely+0x0000000000000060
  0000000000000018 R_PPC64_ADDR64    .text.unlikely+0x00000000000000b4
  0000000000000020 R_PPC64_ADDR64    .init.text+0x0000000000000008
  0000000000000028 R_PPC64_ADDR64    .init.text+0x0000000000000014

The first entry in each section is incorrect. Looking at the
relocation records, the spurious entries correspond to the
R_PPC64_ENTRY records:

  RELOCATION RECORDS FOR [.text.unlikely]:
  OFFSET           TYPE              VALUE
  0000000000000000 R_PPC64_REL64     .TOC.-0x0000000000000008
  0000000000000008 R_PPC64_ENTRY     *ABS*
  0000000000000014 R_PPC64_REL24     _mcount
  <snip>

The problem is that we are not validating the return value from
get_mcountsym() in sift_rel_mcount(). With this entry, mcountsym is 0,
but Elf_r_sym(relp) also ends up being 0. Fix this by ensuring
mcountsym is valid before processing the entry.

Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Acked-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Tested-by: Satheesh Rajendran <sathnaga@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-07-31 07:28:53 +02:00
Manuel Traut
793ff5efee scripts/decode_stacktrace.sh: prefix addr2line with $CROSS_COMPILE
[ Upstream commit c04e32e911 ]

At least for ARM64 kernels compiled with the crosstoolchain from
Debian/stretch or with the toolchain from kernel.org the line number is
not decoded correctly by 'decode_stacktrace.sh':

  $ echo "[  136.513051]  f1+0x0/0xc [kcrash]" | \
    CROSS_COMPILE=/opt/gcc-8.1.0-nolibc/aarch64-linux/bin/aarch64-linux- \
   ./scripts/decode_stacktrace.sh /scratch/linux-arm64/vmlinux \
                                  /scratch/linux-arm64 \
                                  /nfs/debian/lib/modules/4.20.0-devel
  [  136.513051] f1 (/linux/drivers/staging/kcrash/kcrash.c:68) kcrash

If addr2line from the toolchain is used the decoded line number is correct:

  [  136.513051] f1 (/linux/drivers/staging/kcrash/kcrash.c:57) kcrash

Link: http://lkml.kernel.org/r/20190527083425.3763-1-manut@linutronix.de
Signed-off-by: Manuel Traut <manut@linutronix.de>
Acked-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-07-10 09:54:36 +02:00
George G. Davis
4fea6066fb scripts/checkstack.pl: Fix arm64 wrong or unknown architecture
[ Upstream commit 4f45d62a52 ]

The following error occurs for the `make ARCH=arm64 checkstack` case:

aarch64-linux-gnu-objdump -d vmlinux $(find . -name '*.ko') | \
perl ./scripts/checkstack.pl arm64
wrong or unknown architecture "arm64"

As suggested by Masahiro Yamada, fix the above error using regular
expressions in the same way it was fixed for the `ARCH=x86` case via
commit fda9f9903b ("scripts/checkstack.pl: automatically handle
32-bit and 64-bit mode for ARCH=x86").

Suggested-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: George G. Davis <george_davis@mentor.com>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-06-25 11:36:53 +08:00
Kirill Smelkov
b673f99cec fs: stream_open - opener for stream-like files so that read and write can run simultaneously without deadlock
commit 10dce8af34 upstream.

Commit 9c225f2655 ("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 581d21a2d0 ("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 9c225f2655 -
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 -> 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 a7c1b990f7 ("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 &~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 < 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 <mtk.manpages@gmail.com>
Cc: Yongzhi Pan <panyongzhi@gmail.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: David Vrabel <david.vrabel@citrix.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Miklos Szeredi <miklos@szeredi.hu>
Cc: Tejun Heo <tj@kernel.org>
Cc: Kirill Tkhai <ktkhai@virtuozzo.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Julia Lawall <Julia.Lawall@lip6.fr>
Cc: Nikolaus Rath <Nikolaus@rath.org>
Cc: Han-Wen Nienhuys <hanwen@google.com>
Signed-off-by: Kirill Smelkov <kirr@nexedi.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-11 12:21:51 +02:00
Kees Cook
ed69b64c3c gcc-plugins: Fix build failures under Darwin host
commit 7210e06015 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" <hns@goldelico.com>
Fixes: 189af46571 ("ARM: smp: add support for per-task stack canaries")
Cc: stable@vger.kernel.org
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-09 09:18:19 +02:00
Changbin Du
03f9b44775 kconfig/[mn]conf: handle backspace (^H) key
[ Upstream commit 9c38f1f044 ]

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 <changbin.du@gmail.com>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Sasha Levin (Microsoft) <sashal@kernel.org>
2019-05-04 09:15:22 +02:00
Paulo Alcantara
760f8522ce selinux: use kernel linux/socket.h for genheaders and mdp
commit dfbd199a7c 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 <paulo@paulo.ac>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
[PM: manually merge in mdp.c, subject line tweaks]
Signed-off-by: Paul Moore <paul@paul-moore.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-04 09:15:17 +02:00
Masahiro Yamada
1f855871fc kbuild: simplify ld-option implementation
commit 0294e6f4a0 upstream.

Currently, linker options are tested by the coordination of $(CC) and
$(LD) because $(LD) needs some object to link.

As commit 86a9df597c ("kbuild: fix linker feature test macros when
cross compiling with Clang") addressed, we need to make sure $(CC)
and $(LD) agree the underlying architecture of the passed object.

This could be a bit complex when we combine tools from different groups.
For example, we can use clang for $(CC), but we still need to rely on
GCC toolchain for $(LD).

So, I was searching for a way of standalone testing of linker options.
A trick I found is to use '-v'; this not only prints the version string,
but also tests if the given option is recognized.

If a given option is supported,

  $ aarch64-linux-gnu-ld -v --fix-cortex-a53-843419
  GNU ld (Linaro_Binutils-2017.11) 2.28.2.20170706
  $ echo $?
  0

If unsupported,

  $ aarch64-linux-gnu-ld -v --fix-cortex-a53-843419
  GNU ld (crosstool-NG linaro-1.13.1-4.7-2013.04-20130415 - Linaro GCC 2013.04) 2.23.1
  aarch64-linux-gnu-ld: unrecognized option '--fix-cortex-a53-843419'
  aarch64-linux-gnu-ld: use the --help option for usage information
  $ echo $?
  1

Gold works likewise.

  $ aarch64-linux-gnu-ld.gold -v --fix-cortex-a53-843419
  GNU gold (Linaro_Binutils-2017.11 2.28.2.20170706) 1.14
  masahiro@pug:~/ref/linux$ echo $?
  0
  $ aarch64-linux-gnu-ld.gold -v --fix-cortex-a53-999999
  GNU gold (Linaro_Binutils-2017.11 2.28.2.20170706) 1.14
  aarch64-linux-gnu-ld.gold: --fix-cortex-a53-999999: unknown option
  aarch64-linux-gnu-ld.gold: use the --help option for usage information
  $ echo $?
  1

LLD too.

  $ ld.lld -v --gc-sections
  LLD 7.0.0 (http://llvm.org/git/lld.git 4a0e4190e74cea19f8a8dc625ccaebdf8b5d1585) (compatible with GNU linkers)
  $ echo $?
  0
  $ ld.lld -v --fix-cortex-a53-843419
  LLD 7.0.0 (http://llvm.org/git/lld.git 4a0e4190e74cea19f8a8dc625ccaebdf8b5d1585) (compatible with GNU linkers)
  $ echo $?
  0
  $ ld.lld -v --fix-cortex-a53-999999
  ld.lld: error: unknown argument: --fix-cortex-a53-999999
  LLD 7.0.0 (http://llvm.org/git/lld.git 4a0e4190e74cea19f8a8dc625ccaebdf8b5d1585) (compatible with GNU linkers)
  $ echo $?
  1

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Tested-by: Nick Desaulniers <ndesaulniers@google.com>
[nc: try-run-cached was added later, just use try-run, which is the
     current mainline state]
Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-02 09:40:27 +02:00
Masahiro Yamada
10bd1c7ad3 modpost: file2alias: check prototype of handler
commit f880eea68f upstream.

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

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Mathieu Malaterre <malat@debian.org>
Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-04-27 09:35:39 +02:00
Masahiro Yamada
1a7fe5cb7a modpost: file2alias: go back to simple devtable lookup
commit ec91e78d37 upstream.

Commit e49ce14150 ("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 dd2a3acaec ("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 <yamada.masahiro@socionext.com>
Acked-by: Mathieu Malaterre <malat@debian.org>
[nc: Omit rpmsg, sdw, tbsvc, and typec as they do not exist here]
Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-04-27 09:35:39 +02:00
Fredrik Noring
e75c894d81 kbuild: modversions: Fix relative CRC byte order interpretation
commit 54a7151b14 upstream.

Fix commit 56067812d5 ("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: 56067812d5 ("kbuild: modversions: add infrastructure for emitting relative CRCs")
Signed-off-by: Fredrik Noring <noring@nocrew.org>
Cc: stable@vger.kernel.org
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-04-03 06:25:17 +02:00
Du Changbin
179c71c5a2 scripts/gdb: fix lx-version string output
[ Upstream commit b058809bfc ]

A bug is present in GDB which causes early string termination when
parsing variables.  This has been reported [0], but we should ensure
that we can support at least basic printing of the core kernel strings.

For current gdb version (has been tested with 7.3 and 8.1), 'lx-version'
only prints one character.

  (gdb) lx-version
  L(gdb)

This can be fixed by casting 'linux_banner' as (char *).

  (gdb) lx-version
  Linux version 4.19.0-rc1+ (changbin@acer) (gcc version 7.3.0 (Ubuntu 7.3.0-16ubuntu3)) #21 SMP Sat Sep 1 21:43:30 CST 2018

[0] https://sourceware.org/bugzilla/show_bug.cgi?id=20077

[kbingham@kernel.org: add detail to commit message]
Link: http://lkml.kernel.org/r/20181111162035.8356-1-kieran.bingham@ideasonboard.com
Fixes: 2d061d9994 ("scripts/gdb: add version command")
Signed-off-by: Du Changbin <changbin.du@gmail.com>
Signed-off-by: Kieran Bingham <kbingham@kernel.org>
Acked-by: Jan Kiszka <jan.kiszka@siemens.com>
Cc: Jan Kiszka <jan.kiszka@siemens.com>
Cc: Jason Wessel <jason.wessel@windriver.com>
Cc: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-02-12 19:46:10 +01:00
Marc Zyngier
6c16674b6b scripts/decode_stacktrace: only strip base path when a prefix of the path
[ Upstream commit 67a28de47f ]

Running something like:

	decodecode vmlinux .

leads to interested results where not only the leading "." gets stripped
from the displayed paths, but also anywhere in the string, displaying
something like:

	kvm_vcpu_check_block (arch/arm64/kvm/virt/kvm/kvm_mainc:2141)

which doesn't help further processing.

Fix it by only stripping the base path if it is a prefix of the path.

Link: http://lkml.kernel.org/r/20181210174659.31054-3-marc.zyngier@arm.com
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-02-12 19:46:08 +01:00
Sami Tolvanen
20a7ded03f modpost: validate symbol names also in find_elf_symbol
[ Upstream commit 5818c683a6 ]

If an ARM mapping symbol shares an address with a valid symbol,
find_elf_symbol can currently return the mapping symbol instead, as the
symbol is not validated. This can result in confusing warnings:

  WARNING: vmlinux.o(.text+0x18f4028): Section mismatch in reference
  from the function set_reset_devices() to the variable .init.text:$x.0

This change adds a call to is_valid_name to find_elf_symbol, similarly
to how it's already used in find_elf_symbol2.

Signed-off-by: Sami Tolvanen <samitolvanen@google.com>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-02-12 19:45:59 +01:00
Masahiro Yamada
3f96ff44bb kconfig: fix memory leak when EOF is encountered in quotation
[ Upstream commit fbac5977d8 ]

An unterminated string literal followed by new line is passed to the
parser (with "multi-line strings not supported" warning shown), then
handled properly there.

On the other hand, an unterminated string literal at end of file is
never passed to the parser, then results in memory leak.

[Test Code]

  ----------(Kconfig begin)----------
  source "Kconfig.inc"

  config A
          bool "a"
  -----------(Kconfig end)-----------

  --------(Kconfig.inc begin)--------
  config B
          bool "b\No new line at end of file
  ---------(Kconfig.inc end)---------

[Summary from Valgrind]

  Before the fix:

    LEAK SUMMARY:
       definitely lost: 16 bytes in 1 blocks
       ...

  After the fix:

    LEAK SUMMARY:
       definitely lost: 0 bytes in 0 blocks
       ...

Eliminate the memory leak path by handling this case. Of course, such
a Kconfig file is wrong already, so I will add an error message later.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-01-26 09:37:04 +01:00
Masahiro Yamada
407148e8c0 kconfig: fix file name and line number of warn_ignored_character()
[ Upstream commit 77c1c0fa8b ]

Currently, warn_ignore_character() displays invalid file name and
line number.

The lexer should use current_file->name and yylineno, while the parser
should use zconf_curname() and zconf_lineno().

This difference comes from that the lexer is always going ahead
of the parser. The parser needs to look ahead one token to make a
shift/reduce decision, so the lexer is requested to scan more text
from the input file.

This commit fixes the warning message from warn_ignored_character().

[Test Code]

  ----(Kconfig begin)----
  /
  -----(Kconfig end)-----

[Output]

  Before the fix:

  <none>:0:warning: ignoring unsupported character '/'

  After the fix:

  Kconfig:1:warning: ignoring unsupported character '/'

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-01-26 09:37:04 +01:00
WANG Chao
64ac5483a1 x86, modpost: Replace last remnants of RETPOLINE with CONFIG_RETPOLINE
commit e4f358916d upstream.

Commit

  4cd24de3a0 ("x86/retpoline: Make CONFIG_RETPOLINE depend on compiler support")

replaced the RETPOLINE define with CONFIG_RETPOLINE checks. Remove the
remaining pieces.

 [ bp: Massage commit message. ]

Fixes: 4cd24de3a0 ("x86/retpoline: Make CONFIG_RETPOLINE depend on compiler support")
Signed-off-by: WANG Chao <chao.wang@ucloud.cn>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Zhenzhong Duan <zhenzhong.duan@oracle.com>
Reviewed-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: David Woodhouse <dwmw@amazon.co.uk>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Jessica Yu <jeyu@kernel.org>
Cc: Jiri Kosina <jkosina@suse.cz>
Cc: Kees Cook <keescook@chromium.org>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Luc Van Oostenryck <luc.vanoostenryck@gmail.com>
Cc: Michal Marek <michal.lkml@markovi.net>
Cc: Miguel Ojeda <miguel.ojeda.sandonis@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Tim Chen <tim.c.chen@linux.intel.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: linux-kbuild@vger.kernel.org
Cc: srinivas.eeda@oracle.com
Cc: stable <stable@vger.kernel.org>
Cc: x86-ml <x86@kernel.org>
Link: https://lkml.kernel.org/r/20181210163725.95977-1-chao.wang@ucloud.cn
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-01-16 22:07:10 +01:00
Ard Biesheuvel
28493b4147 scripts/kallsyms: filter arm64's __efistub_ symbols
commit 1212f7a16a upstream.

On arm64, the EFI stub and the kernel proper are essentially the same
binary, although the EFI stub executes at a different virtual address
as the kernel. For this reason, the EFI stub is restricted in the
symbols it can link to, which is ensured by prefixing all EFI stub
symbols with __efistub_ (and emitting __efistub_ prefixed aliases for
routines that may be shared between the core kernel and the stub)

These symbols are leaking into kallsyms, polluting the namespace, so
let's filter them explicitly.

Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Cc: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-01-13 10:01:06 +01:00
Joel Stanley
487467e7d0 ftrace: Build with CPPFLAGS to get -Qunused-arguments
When building to record the mcount locations the kernel uses
KBUILD_CFLAGS but not KBUILD_CPPFLAGS. This means it lacks
-Qunused-arguments when building with clang, resulting in a lot of
noisy warnings.

Signed-off-by: Joel Stanley <joel@jms.id.au>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
[nc: Fix conflicts due to lack of 87a32e6240 and d503ac531a]
Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-01-13 10:01:03 +01:00
Qian Cai
7932e14f9f checkstack.pl: fix for aarch64
[ Upstream commit f1733a1d3c ]

There is actually a space after "sp," like this,

    ffff2000080813c8:       a9bb7bfd        stp     x29, x30, [sp, #-80]!

Right now, checkstack.pl isn't able to print anything on aarch64,
because it won't be able to match the stating objdump line of a function
due to this missing space.  Hence, it displays every stack as zero-size.

After this patch, checkpatch.pl is able to match the start of a
function's objdump, and is then able to calculate each function's stack
correctly.

Link: http://lkml.kernel.org/r/20181207195843.38528-1-cai@lca.pw
Signed-off-by: Qian Cai <cai@lca.pw>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-01-13 10:00:57 +01:00
Linus Torvalds
f5028606c2 unifdef: use memcpy instead of strncpy
commit 38c7b224ce upstream.

New versions of gcc reasonably warn about the odd pattern of

	strncpy(p, q, strlen(q));

which really doesn't make sense: the strncpy() ends up being just a slow
and odd way to write memcpy() in this case.

There was a comment about _why_ the code used strncpy - to avoid the
terminating NUL byte, but memcpy does the same and avoids the warning.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-12-08 13:03:35 +01:00
Xiongfeng Wang
f5ec9987bf Kbuild: suppress packed-not-aligned warning for default setting only
commit 321cb0308a upstream.

gcc-8 reports many -Wpacked-not-aligned warnings. The below are some
examples.

./include/linux/ceph/msgr.h:67:1: warning: alignment 1 of 'struct
ceph_entity_addr' is less than 8 [-Wpacked-not-aligned]
 } __attribute__ ((packed));

./include/linux/ceph/msgr.h:67:1: warning: alignment 1 of 'struct
ceph_entity_addr' is less than 8 [-Wpacked-not-aligned]
 } __attribute__ ((packed));

./include/linux/ceph/msgr.h:67:1: warning: alignment 1 of 'struct
ceph_entity_addr' is less than 8 [-Wpacked-not-aligned]
 } __attribute__ ((packed));

This patch suppresses this kind of warnings for default setting.

Signed-off-by: Xiongfeng Wang <xiongfeng.wang@linaro.org>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-12-08 13:03:34 +01:00
Zhenzhong Duan
a9c90037af x86/retpoline: Make CONFIG_RETPOLINE depend on compiler support
commit 4cd24de3a0 upstream

Since retpoline capable compilers are widely available, make
CONFIG_RETPOLINE hard depend on the compiler capability.

Break the build when CONFIG_RETPOLINE is enabled and the compiler does not
support it. Emit an error message in that case:

 "arch/x86/Makefile:226: *** You are building kernel with non-retpoline
  compiler, please update your compiler..  Stop."

[dwmw: Fail the build with non-retpoline compiler]

Suggested-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Zhenzhong Duan <zhenzhong.duan@oracle.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: David Woodhouse <dwmw@amazon.co.uk>
Cc: Borislav Petkov <bp@suse.de>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Masahiro Yamada <yamada.masahiro@socionext.com>
Cc: Michal Marek <michal.lkml@markovi.net>
Cc: <srinivas.eeda@oracle.com>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/cca0cb20-f9e2-4094-840b-fb0f8810cd34@default
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-12-05 19:41:19 +01:00
Masahiro Yamada
48f1b3b56e kconfig: fix the rule of mainmenu_stmt symbol
[ Upstream commit 56869d45e3 ]

The rule of mainmenu_stmt does not have debug print of zconf_lineno(),
but if it had, it would print a wrong line number for the same reason
as commit b2d00d7c61 ("kconfig: fix line numbers for if-entries in
menu tree").

The mainmenu_stmt does not need to eat following empty lines because
they are reduced to common_stmt.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2018-11-04 14:52:45 +01:00
Masahiro Yamada
ee83ce188e kbuild: add .DELETE_ON_ERROR special target
[ Upstream commit 9c2af1c737 ]

If Make gets a fatal signal while a shell is executing, it may delete
the target file that the recipe was supposed to update.  This is needed
to make sure that it is remade from scratch when Make is next run; if
Make is interrupted after the recipe has begun to write the target file,
it results in an incomplete file whose time stamp is newer than that
of the prerequisites files.  Make automatically deletes the incomplete
file on interrupt unless the target is marked .PRECIOUS.

The situation is just the same as when the shell fails for some reasons.
Usually when a recipe line fails, if it has changed the target file at
all, the file is corrupted, or at least it is not completely updated.
Yet the file’s time stamp says that it is now up to date, so the next
time Make runs, it will not try to update that file.

However, Make does not cater to delete the incomplete target file in
this case.  We need to add .DELETE_ON_ERROR somewhere in the Makefile
to request it.

scripts/Kbuild.include seems a suitable place to add it because it is
included from almost all sub-makes.

Please note .DELETE_ON_ERROR is not effective for phony targets.

The external module building should never ever touch the kernel tree.
The following recipe fails if include/generated/autoconf.h is missing.
However, include/config/auto.conf is not deleted since it is a phony
target.

 PHONY += include/config/auto.conf

 include/config/auto.conf:
         $(Q)test -e include/generated/autoconf.h -a -e $@ || (          \
         echo >&2;                                                       \
         echo >&2 "  ERROR: Kernel configuration is invalid.";           \
         echo >&2 "         include/generated/autoconf.h or $@ are missing.";\
         echo >&2 "         Run 'make oldconfig && make prepare' on kernel src to fix it."; \
         echo >&2 ;                                                      \
         /bin/false)

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-26 08:37:59 +02:00
Randy Dunlap
9370868fd3 kbuild: make missing $DEPMOD a Warning instead of an Error
commit 914b087ff9 upstream.

When $DEPMOD is not found, only print a warning instead of exiting
with an error message and error status:

Warning: 'make modules_install' requires /sbin/depmod. Please install it.
This is probably in the kmod package.

Change the Error to a Warning because "not all build hosts for cross
compiling Linux are Linux systems and are able to provide a working
port of depmod, especially at the file patch /sbin/depmod."

I.e., "make modules_install" may be used to copy/install the
loadable modules files to a target directory on a build system and
then transferred to an embedded device where /sbin/depmod is run
instead of it being run on the build system.

Fixes: 934193a654 ("kbuild: verify that $DEPMOD is installed")
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Reported-by: H. Nikolaus Schaller <hns@goldelico.com>
Cc: stable@vger.kernel.org
Cc: Lucas De Marchi <lucas.demarchi@profusion.mobi>
Cc: Lucas De Marchi <lucas.de.marchi@gmail.com>
Cc: Michal Marek <michal.lkml@markovi.net>
Cc: Jessica Yu <jeyu@kernel.org>
Cc: Chih-Wei Huang <cwhuang@linux.org.tw>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Maxim Zhukov <mussitantesmortem@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-15 09:45:36 +02:00
Randy Dunlap
ab4bddc2d0 scripts: modpost: check memory allocation results
[ Upstream commit 1f3aa9002d ]

Fix missing error check for memory allocation functions in
scripts/mod/modpost.c.

Fixes kernel bugzilla #200319:
https://bugzilla.kernel.org/show_bug.cgi?id=200319

Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Yuexing Wang <wangyxlandq@gmail.com>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-15 09:45:27 +02:00
Kees Cook
77d1658e5d gcc-plugins: Use dynamic initializers
commit b86729109c upstream.

GCC 8 changed the order of some fields and is very picky about ordering
in static initializers, so instead just move to dynamic initializers,
and drop the redundant already-zero field assignments.

Suggested-by: Valdis Kletnieks <valdis.kletnieks@vt.edu>
Signed-off-by: Kees Cook <keescook@chromium.org>
Cc: Lance Albertson <lance@osuosl.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-05 09:26:42 +02:00
Valdis Kletnieks
616d41d1b4 gcc-plugins: Add include required by GCC release 8
commit 80d1724316 upstream.

GCC requires another #include to get the gcc-plugins to build cleanly.

Signed-off-by: Valdis Kletnieks <valdis.kletnieks@vt.edu>
Signed-off-by: Kees Cook <keescook@chromium.org>
Cc: Lance Albertson <lance@osuosl.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-05 09:26:42 +02:00
Dirk Gouders
2f9e98dbcc kconfig: fix line numbers for if-entries in menu tree
[ Upstream commit b2d00d7c61 ]

The line numers for if-entries in the menu tree are off by one or more
lines which is confusing when debugging for correctness of unrelated changes.

According to the git log, commit a02f0570ae (kconfig: improve
error handling in the parser) was the last one that changed that part
of the parser and replaced

	"if_entry: T_IF expr T_EOL"
by
	"if_entry: T_IF expr nl"

but the commit message does not state why this has been done.

When reverting that part of the commit, only the line numers are
corrected (checked with cdebug = DEBUG_PARSE in zconf.y), otherwise
the menu tree remains unchanged (checked with zconfdump() enabled in
conf.c).

An example for the corrected line numbers:

drivers/soc/Kconfig:15:source drivers/soc/tegra/Kconfig
drivers/soc/tegra/Kconfig:4:if
drivers/soc/tegra/Kconfig:6:if

changes to:

drivers/soc/Kconfig:15:source drivers/soc/tegra/Kconfig
drivers/soc/tegra/Kconfig:1:if
drivers/soc/tegra/Kconfig:4:if

Signed-off-by: Dirk Gouders <dirk@gouders.net>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-08-24 13:09:06 +02:00
Randy Dunlap
50123ab8c4 kbuild: verify that $DEPMOD is installed
commit 934193a654 upstream.

Verify that 'depmod' ($DEPMOD) is installed.
This is a partial revert of commit 620c231c7a
("kbuild: do not check for ancient modutils tools").

Also update Documentation/process/changes.rst to refer to
kmod instead of module-init-tools.

Fixes kernel bugzilla #198965:
https://bugzilla.kernel.org/show_bug.cgi?id=198965

Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Lucas De Marchi <lucas.demarchi@profusion.mobi>
Cc: Lucas De Marchi <lucas.de.marchi@gmail.com>
Cc: Michal Marek <michal.lkml@markovi.net>
Cc: Jessica Yu <jeyu@kernel.org>
Cc: Chih-Wei Huang <cwhuang@linux.org.tw>
Cc: stable@vger.kernel.org # any kernel since 2012
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-08-17 21:01:10 +02:00
Rasmus Villemoes
e82885490a Kbuild: fix # escaping in .cmd files for future Make
commit 9564a8cf42 upstream.

I tried building using a freshly built Make (4.2.1-69-g8a731d1), but
already the objtool build broke with

orc_dump.c: In function ‘orc_dump’:
orc_dump.c:106:2: error: ‘elf_getshnum’ is deprecated [-Werror=deprecated-declarations]
  if (elf_getshdrnum(elf, &nr_sections)) {

Turns out that with that new Make, the backslash was not removed, so cpp
didn't see a #include directive, grep found nothing, and
-DLIBELF_USE_DEPRECATED was wrongly put in CFLAGS.

Now, that new Make behaviour is documented in their NEWS file:

  * WARNING: Backward-incompatibility!
    Number signs (#) appearing inside a macro reference or function invocation
    no longer introduce comments and should not be escaped with backslashes:
    thus a call such as:
      foo := $(shell echo '#')
    is legal.  Previously the number sign needed to be escaped, for example:
      foo := $(shell echo '\#')
    Now this latter will resolve to "\#".  If you want to write makefiles
    portable to both versions, assign the number sign to a variable:
      C := \#
      foo := $(shell echo '$C')
    This was claimed to be fixed in 3.81, but wasn't, for some reason.
    To detect this change search for 'nocomment' in the .FEATURES variable.

This also fixes up the two make-cmd instances to replace # with $(pound)
rather than with \#. There might very well be other places that need
similar fixup in preparation for whatever future Make release contains
the above change, but at least this builds an x86_64 defconfig with the
new make.

Link: https://bugzilla.kernel.org/show_bug.cgi?id=197847
Cc: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-07-11 16:29:21 +02:00
Nathan Chancellor
d58cf41924 kconfig: Avoid format overflow warning from GCC 8.1
commit 2ae89c7a82 upstream.

In file included from scripts/kconfig/zconf.tab.c:2485:
scripts/kconfig/confdata.c: In function ‘conf_write’:
scripts/kconfig/confdata.c:773:22: warning: ‘%s’ directive writing likely 7 or more bytes into a region of size between 1 and 4097 [-Wformat-overflow=]
  sprintf(newname, "%s%s", dirname, basename);
                      ^~
scripts/kconfig/confdata.c:773:19: note: assuming directive output of 7 bytes
  sprintf(newname, "%s%s", dirname, basename);
                   ^~~~~~
scripts/kconfig/confdata.c:773:2: note: ‘sprintf’ output 1 or more bytes (assuming 4104) into a destination of size 4097
  sprintf(newname, "%s%s", dirname, basename);
  ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
scripts/kconfig/confdata.c:776:23: warning: ‘.tmpconfig.’ directive writing 11 bytes into a region of size between 1 and 4097 [-Wformat-overflow=]
   sprintf(tmpname, "%s.tmpconfig.%d", dirname, (int)getpid());
                       ^~~~~~~~~~~
scripts/kconfig/confdata.c:776:3: note: ‘sprintf’ output between 13 and 4119 bytes into a destination of size 4097
   sprintf(tmpname, "%s.tmpconfig.%d", dirname, (int)getpid());
   ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Increase the size of tmpname and newname to make GCC happy.

Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-06-11 22:49:18 +02:00
Jan Kiszka
38a85f8214 builddeb: Fix header package regarding dtc source links
[ Upstream commit f843752070 ]

Since d5d332d3f7, a couple of links in scripts/dtc/include-prefixes
are additionally required in order to build device trees with the header
package.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Reviewed-by: Riku Voipio <riku.voipio@linaro.org>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-05-30 07:52:21 +02:00
Nicolas Pitre
405544d5f8 kbuild: make scripts/adjust_autoksyms.sh robust against timestamp races
[ Upstream commit 825d487583 ]

Some filesystems have timestamps with coarse precision that may allow
for a recently built object file to have the same timestamp as the
updated time on one of its dependency files. When that happens, the
object file doesn't get rebuilt as it should.

This is especially the case on filesystems that don't have sub-second
time precision, such as ext3 or Ext4 with 128B inodes.

Let's prevent that by making sure updated dependency files have a newer
timestamp than the first file we created (i.e. autoksyms.h.tmpnew).

Reported-by: Thomas Lindroth <thomas.lindroth@gmail.com>
Signed-off-by: Nicolas Pitre <nico@linaro.org>
Tested-by: Thomas Lindroth <thomas.lindroth@gmail.com>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-05-30 07:52:17 +02:00
Ulf Magnusson
18004e6f26 kconfig: Fix expr_free() E_NOT leak
[ Upstream commit 5b1374b3b3 ]

Only the E_NOT operand and not the E_NOT node itself was freed, due to
accidentally returning too early in expr_free(). Outline of leak:

	switch (e->type) {
	...
	case E_NOT:
		expr_free(e->left.expr);
		return;
	...
	}
	*Never reached, 'e' leaked*
	free(e);

Fix by changing the 'return' to a 'break'.

Summary from Valgrind on 'menuconfig' (ARCH=x86) before the fix:

	LEAK SUMMARY:
	   definitely lost: 44,448 bytes in 1,852 blocks
	   ...

Summary after the fix:

	LEAK SUMMARY:
	   definitely lost: 1,608 bytes in 67 blocks
	   ...

Signed-off-by: Ulf Magnusson <ulfalizer@gmail.com>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-04-26 11:02:08 +02:00
Ulf Magnusson
0f511f3dda kconfig: Fix automatic menu creation mem leak
[ Upstream commit ae7440ef0c ]

expr_trans_compare() always allocates and returns a new expression,
giving the following leak outline:

	...
	*Allocate*
	basedep = expr_trans_compare(basedep, E_UNEQUAL, &symbol_no);
	...
	for (menu = parent->next; menu; menu = menu->next) {
		...
		*Copy*
		dep2 = expr_copy(basedep);
		...
		*Free copy*
		expr_free(dep2);
	}
	*basedep lost!*

Fix by freeing 'basedep' after the loop.

Summary from Valgrind on 'menuconfig' (ARCH=x86) before the fix:

	LEAK SUMMARY:
	   definitely lost: 344,376 bytes in 14,349 blocks
	   ...

Summary after the fix:

	LEAK SUMMARY:
	   definitely lost: 44,448 bytes in 1,852 blocks
	   ...

Signed-off-by: Ulf Magnusson <ulfalizer@gmail.com>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-04-26 11:02:08 +02:00
Ulf Magnusson
8bf116b258 kconfig: Don't leak main menus during parsing
[ Upstream commit 0724a7c32a ]

If a 'mainmenu' entry appeared in the Kconfig files, two things would
leak:

	- The 'struct property' allocated for the default "Linux Kernel
	  Configuration" prompt.

	- The string for the T_WORD/T_WORD_QUOTE prompt after the
	  T_MAINMENU token, allocated on the heap in zconf.l.

To fix it, introduce a new 'no_mainmenu_stmt' nonterminal that matches
if there's no 'mainmenu' and adds the default prompt. That means the
prompt only gets allocated once regardless of whether there's a
'mainmenu' statement or not, and managing it becomes simple.

Summary from Valgrind on 'menuconfig' (ARCH=x86) before the fix:

	LEAK SUMMARY:
	   definitely lost: 344,568 bytes in 14,352 blocks
	   ...

Summary after the fix:

	LEAK SUMMARY:
	   definitely lost: 344,440 bytes in 14,350 blocks
	   ...

Signed-off-by: Ulf Magnusson <ulfalizer@gmail.com>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-04-26 11:02:08 +02:00
Nick Desaulniers
957435b566 kbuild: fix linker feature test macros when cross compiling with Clang
commit 86a9df597c upstream.

I was not seeing my linker flags getting added when using ld-option when
cross compiling with Clang. Upon investigation, this seems to be due to
a difference in how GCC vs Clang handle cross compilation.

GCC is configured at build time to support one backend, that is implicit
when compiling.  Clang is explicit via the use of `-target <triple>` and
ships with all supported backends by default.

GNU Make feature test macros that compile then link will always fail
when cross compiling with Clang unless Clang's triple is passed along to
the compiler. For example:

$ clang -x c /dev/null -c -o temp.o
$ aarch64-linux-android/bin/ld -E temp.o
aarch64-linux-android/bin/ld:
unknown architecture of input file `temp.o' is incompatible with
aarch64 output
aarch64-linux-android/bin/ld:
warning: cannot find entry symbol _start; defaulting to
0000000000400078
$ echo $?
1

$ clang -target aarch64-linux-android- -x c /dev/null -c -o temp.o
$ aarch64-linux-android/bin/ld -E temp.o
aarch64-linux-android/bin/ld:
warning: cannot find entry symbol _start; defaulting to 00000000004002e4
$ echo $?
0

This causes conditional checks that invoke $(CC) without the target
triple, then $(LD) on the result, to always fail.

Suggested-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Nick Desaulniers <ndesaulniers@google.com>
Reviewed-by: Matthias Kaehlcke <mka@chromium.org>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Greg Hackmann <ghackmann@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-03-24 11:01:29 +01:00
Peter Zijlstra
c3b9f72606 objtool, retpolines: Integrate objtool with retpoline support more closely
commit d5028ba8ee upstream.

Disable retpoline validation in objtool if your compiler sucks, and otherwise
select the validation stuff for CONFIG_RETPOLINE=y (most builds would already
have it set due to ORC).

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-03-15 10:54:38 +01:00
Peter Zijlstra
a69898c9eb objtool: Add module specific retpoline rules
commit ca41b97ed9 upstream.

David allowed retpolines in .init.text, except for modules, which will
trip up objtool retpoline validation, fix that.

Requested-by: David Woodhouse <dwmw2@infradead.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-03-15 10:54:38 +01:00
Peter Zijlstra
e6993149fa objtool: Add retpoline validation
commit b5bc2231b8 upstream.

David requested a objtool validation pass for CONFIG_RETPOLINE=y enabled
builds, where it validates no unannotated indirect  jumps or calls are
left.

Add an additional .discard.retpoline_safe section to allow annotating
the few indirect sites that are required and safe.

Requested-by: David Woodhouse <dwmw2@infradead.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: David Woodhouse <dwmw@amazon.co.uk>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-03-15 10:54:37 +01:00
James Hogan
ffced04184 kbuild: Handle builtin dtb file names containing hyphens
commit 55fe6da9ef upstream.

cmd_dt_S_dtb constructs the assembly source to incorporate a devicetree
FDT (that is, the .dtb file) as binary data in the kernel image. This
assembly source contains labels before and after the binary data. The
label names incorporate the file name of the corresponding .dtb file.
Hyphens are not legal characters in labels, so .dtb files built into the
kernel with hyphens in the file name result in errors like the
following:

bcm3368-netgear-cvg834g.dtb.S: Assembler messages:
bcm3368-netgear-cvg834g.dtb.S:5: Error: : no such section
bcm3368-netgear-cvg834g.dtb.S:5: Error: junk at end of line, first unrecognized character is `-'
bcm3368-netgear-cvg834g.dtb.S:6: Error: unrecognized opcode `__dtb_bcm3368-netgear-cvg834g_begin:'
bcm3368-netgear-cvg834g.dtb.S:8: Error: unrecognized opcode `__dtb_bcm3368-netgear-cvg834g_end:'
bcm3368-netgear-cvg834g.dtb.S:9: Error: : no such section
bcm3368-netgear-cvg834g.dtb.S:9: Error: junk at end of line, first unrecognized character is `-'

Fix this by updating cmd_dt_S_dtb to transform all hyphens from the file
name to underscores when constructing the labels.

As of v4.16-rc2, 1139 .dts files across ARM64, ARM, MIPS and PowerPC
contain hyphens in their names, but the issue only currently manifests
on Broadcom MIPS platforms, as that is the only place where such files
are built into the kernel. For example when CONFIG_DT_NETGEAR_CVG834G=y,
or on BMIPS kernels when the dtbs target is used (in the latter case it
admittedly shouldn't really build all the dtb.o files, but thats a
separate issue).

Fixes: 695835511f ("MIPS: BMIPS: rename bcm96358nb4ser to bcm6358-neufbox4-sercom")
Signed-off-by: James Hogan <jhogan@kernel.org>
Reviewed-by: Frank Rowand <frowand.list@gmail.com>
Cc: Rob Herring <robh+dt@kernel.org>
Cc: Michal Marek <michal.lkml@markovi.net>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Florian Fainelli <f.fainelli@gmail.com>
Cc: Kevin Cernekee <cernekee@gmail.com>
Cc: <stable@vger.kernel.org> # 4.9+
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-03-15 10:54:33 +01:00
Will Deacon
9537ff76fa scripts/kernel-doc: Don't fail with status != 0 if error encountered with -none
[ Upstream commit e814bccbaf ]

My bisect scripts starting running into build failures when trying to
compile 4.15-rc1 with the builds failing with things like:

drivers/net/wireless/broadcom/brcm80211/brcmfmac/sdio.c:2078: error: Cannot parse struct or union!

The line in question is actually just a #define, but after some digging
it turns out that my scripts pass W=1 and since commit 3a025e1d1c
("Add optional check for bad kernel-doc comments") that results in
kernel-doc running on each source file. The file in question has a
badly formatted comment immediately before the #define:

/**
 * struct brcmf_skbuff_cb reserves first two bytes in sk_buff::cb for
 * bus layer usage.
 */

which causes the regex in dump_struct to fail (lack of braces following
struct declaration) and kernel-doc returns 1, which causes the build
to fail.

Fix the issue by always returning 0 from kernel-doc when invoked with
-none. It successfully generates no documentation, and prints out any
issues.

Cc: Matthew Wilcox <mawilcox@microsoft.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-25 11:07:58 +01:00
Levin, Alexander (Sasha Levin)
f369f14861 kmemcheck: rip it out
commit 4675ff05de upstream.

Fix up makefiles, remove references, and git rm kmemcheck.

Link: http://lkml.kernel.org/r/20171007030159.22241-4-alexander.levin@verizon.com
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Vegard Nossum <vegardno@ifi.uio.no>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Tim Hansen <devtimhansen@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-22 15:42:24 +01:00
Arnd Bergmann
062cd3463c kasan: rework Kconfig settings
commit e7c52b84fb upstream.

We get a lot of very large stack frames using gcc-7.0.1 with the default
-fsanitize-address-use-after-scope --param asan-stack=1 options, which can
easily cause an overflow of the kernel stack, e.g.

  drivers/gpu/drm/i915/gvt/handlers.c:2434:1: warning: the frame size of 46176 bytes is larger than 3072 bytes
  drivers/net/wireless/ralink/rt2x00/rt2800lib.c:5650:1: warning: the frame size of 23632 bytes is larger than 3072 bytes
  lib/atomic64_test.c:250:1: warning: the frame size of 11200 bytes is larger than 3072 bytes
  drivers/gpu/drm/i915/gvt/handlers.c:2621:1: warning: the frame size of 9208 bytes is larger than 3072 bytes
  drivers/media/dvb-frontends/stv090x.c:3431:1: warning: the frame size of 6816 bytes is larger than 3072 bytes
  fs/fscache/stats.c:287:1: warning: the frame size of 6536 bytes is larger than 3072 bytes

To reduce this risk, -fsanitize-address-use-after-scope is now split out
into a separate CONFIG_KASAN_EXTRA Kconfig option, leading to stack
frames that are smaller than 2 kilobytes most of the time on x86_64.  An
earlier version of this patch also prevented combining KASAN_EXTRA with
KASAN_INLINE, but that is no longer necessary with gcc-7.0.1.

All patches to get the frame size below 2048 bytes with CONFIG_KASAN=y
and CONFIG_KASAN_EXTRA=n have been merged by maintainers now, so we can
bring back that default now.  KASAN_EXTRA=y still causes lots of
warnings but now defaults to !COMPILE_TEST to disable it in
allmodconfig, and it remains disabled in all other defconfigs since it
is a new option.  I arbitrarily raise the warning limit for KASAN_EXTRA
to 3072 to reduce the noise, but an allmodconfig kernel still has around
50 warnings on gcc-7.

I experimented a bit more with smaller stack frames and have another
follow-up series that reduces the warning limit for 64-bit architectures
to 1280 bytes (without CONFIG_KASAN).

With earlier versions of this patch series, I also had patches to address
the warnings we get with KASAN and/or KASAN_EXTRA, using a
"noinline_if_stackbloat" annotation.

That annotation now got replaced with a gcc-8 bugfix (see
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=81715) and a workaround for
older compilers, which means that KASAN_EXTRA is now just as bad as
before and will lead to an instant stack overflow in a few extreme
cases.

This reverts parts of commit 3f181b4d86 ("lib/Kconfig.debug: disable
-Wframe-larger-than warnings with KASAN=y").  Two patches in linux-next
should be merged first to avoid introducing warnings in an allmodconfig
build:
  3cd890dbe2 ("media: dvb-frontends: fix i2c access helpers for KASAN")
  16c3ada89c ("media: r820t: fix r820t_write_reg for KASAN")

Do we really need to backport this?

I think we do: without this patch, enabling KASAN will lead to
unavoidable kernel stack overflow in certain device drivers when built
with gcc-7 or higher on linux-4.10+ or any version that contains a
backport of commit c5caf21ab0.  Most people are probably still on
older compilers, but it will get worse over time as they upgrade their
distros.

The warnings we get on kernels older than this should all be for code
that uses dangerously large stack frames, though most of them do not
cause an actual stack overflow by themselves.The asan-stack option was
added in linux-4.0, and commit 3f181b4d86 ("lib/Kconfig.debug:
disable -Wframe-larger-than warnings with KASAN=y") effectively turned
off the warning for allmodconfig kernels, so I would like to see this
fix backported to any kernels later than 4.0.

I have done dozens of fixes for individual functions with stack frames
larger than 2048 bytes with asan-stack, and I plan to make sure that
all those fixes make it into the stable kernels as well (most are
already there).

Part of the complication here is that asan-stack (from 4.0) was
originally assumed to always require much larger stacks, but that
turned out to be a combination of multiple gcc bugs that we have now
worked around and fixed, but sanitize-address-use-after-scope (from
v4.10) has a much higher inherent stack usage and also suffers from at
least three other problems that we have analyzed but not yet fixed
upstream, each of them makes the stack usage more severe than it should
be.

Link: http://lkml.kernel.org/r/20171221134744.2295529-1-arnd@arndb.de
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Mauro Carvalho Chehab <mchehab@kernel.org>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Andrey Konovalov <andreyknvl@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-16 20:23:04 +01:00
Andrey Konovalov
e186d8bfda kasan: don't emit builtin calls when sanitization is off
commit 0e410e158e upstream.

With KASAN enabled the kernel has two different memset() functions, one
with KASAN checks (memset) and one without (__memset).  KASAN uses some
macro tricks to use the proper version where required.  For example
memset() calls in mm/slub.c are without KASAN checks, since they operate
on poisoned slab object metadata.

The issue is that clang emits memset() calls even when there is no
memset() in the source code.  They get linked with improper memset()
implementation and the kernel fails to boot due to a huge amount of KASAN
reports during early boot stages.

The solution is to add -fno-builtin flag for files with KASAN_SANITIZE :=
n marker.

Link: http://lkml.kernel.org/r/8ffecfffe04088c52c42b92739c2bd8a0bcb3f5e.1516384594.git.andreyknvl@google.com
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Acked-by: Nick Desaulniers <ndesaulniers@google.com>
Cc: Masahiro Yamada <yamada.masahiro@socionext.com>
Cc: Michal Marek <michal.lkml@markovi.net>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-16 20:23:04 +01:00
Masahiro Yamada
806d61d669 kbuild: rpm-pkg: keep spec file until make mrproper
commit af60e20708 upstream.

If build fails during (bin)rpm-pkg, the spec file is not cleaned by
anyone until the next successful build of the package.

We do not have to immediately delete the spec file in case somebody
may want to take a look at it.  Instead, make them ignored by git,
and cleaned up by make mrproper.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-13 10:19:46 +01:00
Andi Kleen
86b5b1eb18 module/retpoline: Warn about missing retpoline in module
commit caf7501a1b

There's a risk that a kernel which has full retpoline mitigations becomes
vulnerable when a module gets loaded that hasn't been compiled with the
right compiler or the right option.

To enable detection of that mismatch at module load time, add a module info
string "retpoline" at build time when the module was compiled with
retpoline support. This only covers compiled C source, but assembler source
or prebuilt object files are not checked.

If a retpoline enabled kernel detects a non retpoline protected module at
load time, print a warning and report it in the sysfs vulnerability file.

[ tglx: Massaged changelog ]

Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: gregkh@linuxfoundation.org
Cc: torvalds@linux-foundation.org
Cc: jeyu@kernel.org
Cc: arjan@linux.intel.com
Link: https://lkml.kernel.org/r/20180125235028.31211-1-andi@firstfloor.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-07 11:12:18 -08:00