linux-stable.git/include, branch v4.4.252

vmlinux.lds.h: Add PGO and AutoFDO input sections

2021-01-17T12:55:13+00:00

commit eff8728fe69880d3f7983bec3fb6cea4c306261f upstream.

Basically, consider .text.{hot|unlikely|unknown}.* part of .text, too.

When compiling with profiling information (collected via PGO
instrumentations or AutoFDO sampling), Clang will separate code into
.text.hot, .text.unlikely, or .text.unknown sections based on profiling
information. After D79600 (clang-11), these sections will have a
trailing `.` suffix, ie.  .text.hot., .text.unlikely., .text.unknown..

When using -ffunction-sections together with profiling infomation,
either explicitly (FGKASLR) or implicitly (LTO), code may be placed in
sections following the convention:
.text.hot., .text.unlikely., .text.unknown.
where , , and  are functions.  (This produces one section
per function; we generally try to merge these all back via linker script
so that we don't have 50k sections).

For the above cases, we need to teach our linker scripts that such
sections might exist and that we'd explicitly like them grouped
together, otherwise we can wind up with code outside of the
_stext/_etext boundaries that might not be mapped properly for some
architectures, resulting in boot failures.

If the linker script is not told about possible input sections, then
where the section is placed as output is a heuristic-laiden mess that's
non-portable between linkers (ie. BFD and LLD), and has resulted in many
hard to debug bugs.  Kees Cook is working on cleaning this up by adding
--orphan-handling=warn linker flag used in ARCH=powerpc to additional
architectures. In the case of linker scripts, borrowing from the Zen of
Python: explicit is better than implicit.

Also, ld.bfd's internal linker script considers .text.hot AND
.text.hot.* to be part of .text, as well as .text.unlikely and
.text.unlikely.*. I didn't see support for .text.unknown.*, and didn't
see Clang producing such code in our kernel builds, but I see code in
LLVM that can produce such section names if profiling information is
missing. That may point to a larger issue with generating or collecting
profiles, but I would much rather be safe and explicit than have to
debug yet another issue related to orphan section placement.

Reported-by: Jian Cai 
Suggested-by: Fāng-ruì Sòng 
Signed-off-by: Nick Desaulniers 
Signed-off-by: Kees Cook 
Signed-off-by: Ingo Molnar 
Tested-by: Luis Lozano 
Tested-by: Manoj Gupta 
Acked-by: Kees Cook 
Cc: linux-arch@vger.kernel.org
Cc: stable@vger.kernel.org
Link: https://sourceware.org/git/?p=binutils-gdb.git;a=commitdiff;h=add44f8d5c5c05e08b11e033127a744d61c26aee
Link: https://sourceware.org/git/?p=binutils-gdb.git;a=commitdiff;h=1de778ed23ce7492c523d5850c6c6dbb34152655
Link: https://reviews.llvm.org/D79600
Link: https://bugs.chromium.org/p/chromium/issues/detail?id=1084760
Link: https://lore.kernel.org/r/20200821194310.3089815-7-keescook@chromium.org

Debugged-by: Luis Lozano 
[nc: Fix conflicts around lack of TEXT_MAIN, NOINSTR_TEXT, and
     .text..refcount]
Signed-off-by: Nathan Chancellor 
Signed-off-by: Greg Kroah-Hartman

target: add XCOPY target/segment desc sense codes

2021-01-17T12:55:12+00:00

[ Upstream commit e864212078ded276bdb272b2e0ee6a979357ca8a ]

As defined in http://www.t10.org/lists/asc-num.htm. To be used during
validation of XCOPY target and segment descriptor lists.

Signed-off-by: David Disseldorp 
Reviewed-by: Christoph Hellwig 
Signed-off-by: Bart Van Assche 
Signed-off-by: Sasha Levin

net: sched: prevent invalid Scell_log shift count

2021-01-12T18:47:55+00:00

[ Upstream commit bd1248f1ddbc48b0c30565fce897a3b6423313b8 ]

Check Scell_log shift size in red_check_params() and modify all callers
of red_check_params() to pass Scell_log.

This prevents a shift out-of-bounds as detected by UBSAN:
  UBSAN: shift-out-of-bounds in ./include/net/red.h:252:22
  shift exponent 72 is too large for 32-bit type 'int'

Fixes: 8afa10cbe281 ("net_sched: red: Avoid illegal values")
Signed-off-by: Randy Dunlap 
Reported-by: syzbot+97c5bd9cc81eca63d36e@syzkaller.appspotmail.com
Cc: Nogah Frankel 
Cc: Jamal Hadi Salim 
Cc: Cong Wang 
Cc: Jiri Pirko 
Cc: netdev@vger.kernel.org
Cc: "David S. Miller" 
Cc: Jakub Kicinski 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

of: fix linker-section match-table corruption

2021-01-09T12:34:15+00:00

commit 5812b32e01c6d86ba7a84110702b46d8a8531fe9 upstream.

Specify type alignment when declaring linker-section match-table entries
to prevent gcc from increasing alignment and corrupting the various
tables with padding (e.g. timers, irqchips, clocks, reserved memory).

This is specifically needed on x86 where gcc (typically) aligns larger
objects like struct of_device_id with static extent on 32-byte
boundaries which at best prevents matching on anything but the first
entry. Specifying alignment when declaring variables suppresses this
optimisation.

Here's a 64-bit example where all entries are corrupt as 16 bytes of
padding has been inserted before the first entry:

	ffffffff8266b4b0 D __clk_of_table
	ffffffff8266b4c0 d __of_table_fixed_factor_clk
	ffffffff8266b5a0 d __of_table_fixed_clk
	ffffffff8266b680 d __clk_of_table_sentinel

And here's a 32-bit example where the 8-byte-aligned table happens to be
placed on a 32-byte boundary so that all but the first entry are corrupt
due to the 28 bytes of padding inserted between entries:

	812b3ec0 D __irqchip_of_table
	812b3ec0 d __of_table_irqchip1
	812b3fa0 d __of_table_irqchip2
	812b4080 d __of_table_irqchip3
	812b4160 d irqchip_of_match_end

Verified on x86 using gcc-9.3 and gcc-4.9 (which uses 64-byte
alignment), and on arm using gcc-7.2.

Note that there are no in-tree users of these tables on x86 currently
(even if they are included in the image).

Fixes: 54196ccbe0ba ("of: consolidate linker section OF match table declarations")
Fixes: f6e916b82022 ("irqchip: add basic infrastructure")
Cc: stable      # 3.9
Signed-off-by: Johan Hovold 
Link: https://lore.kernel.org/r/20201123102319.8090-2-johan@kernel.org
[ johan: adjust context to 5.4 ]
Signed-off-by: Johan Hovold 
Signed-off-by: Greg Kroah-Hartman

uapi: move constants from to

2021-01-09T12:34:15+00:00

commit a85cbe6159ffc973e5702f70a3bd5185f8f3c38d upstream.

and include  in UAPI headers instead of .

The reason is to avoid indirect  include when using
some network headers:  or others -> 
-> .

This indirect include causes on MUSL redefinition of struct sysinfo when
included both  and some of UAPI headers:

    In file included from x86_64-buildroot-linux-musl/sysroot/usr/include/linux/kernel.h:5,
                     from x86_64-buildroot-linux-musl/sysroot/usr/include/linux/netlink.h:5,
                     from ../include/tst_netlink.h:14,
                     from tst_crypto.c:13:
    x86_64-buildroot-linux-musl/sysroot/usr/include/linux/sysinfo.h:8:8: error: redefinition of `struct sysinfo'
     struct sysinfo {
            ^~~~~~~
    In file included from ../include/tst_safe_macros.h:15,
                     from ../include/tst_test.h:93,
                     from tst_crypto.c:11:
    x86_64-buildroot-linux-musl/sysroot/usr/include/sys/sysinfo.h:10:8: note: originally defined here

Link: https://lkml.kernel.org/r/20201015190013.8901-1-petr.vorel@gmail.com
Signed-off-by: Petr Vorel 
Suggested-by: Rich Felker 
Acked-by: Rich Felker 
Cc: Peter Korsgaard 
Cc: Baruch Siach 
Cc: Florian Weimer 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds 
Signed-off-by: Greg Kroah-Hartman

xen/xenbus: Count pending messages for each watch

2020-12-29T12:42:45+00:00

commit 3dc86ca6b4c8cfcba9da7996189d1b5a358a94fc upstream.

This commit adds a counter of pending messages for each watch in the
struct.  It is used to skip unnecessary pending messages lookup in
'unregister_xenbus_watch()'.  It could also be used in 'will_handle'
callback.

This is part of XSA-349

Cc: stable@vger.kernel.org
Signed-off-by: SeongJae Park 
Reported-by: Michael Kurth 
Reported-by: Pawel Wieczorkiewicz 
Reviewed-by: Juergen Gross 
Signed-off-by: Juergen Gross 
Signed-off-by: Greg Kroah-Hartman

xen/xenbus: Add 'will_handle' callback support in xenbus_watch_path()

2020-12-29T12:42:45+00:00

commit 2e85d32b1c865bec703ce0c962221a5e955c52c2 upstream.

Some code does not directly make 'xenbus_watch' object and call
'register_xenbus_watch()' but use 'xenbus_watch_path()' instead.  This
commit adds support of 'will_handle' callback in the
'xenbus_watch_path()' and it's wrapper, 'xenbus_watch_pathfmt()'.

This is part of XSA-349

Cc: stable@vger.kernel.org
Signed-off-by: SeongJae Park 
Reported-by: Michael Kurth 
Reported-by: Pawel Wieczorkiewicz 
Reviewed-by: Juergen Gross 
Signed-off-by: Juergen Gross 
Signed-off-by: Greg Kroah-Hartman

xen/xenbus: Allow watches discard events before queueing

2020-12-29T12:42:45+00:00

commit fed1755b118147721f2c87b37b9d66e62c39b668 upstream.

If handling logics of watch events are slower than the events enqueue
logic and the events can be created from the guests, the guests could
trigger memory pressure by intensively inducing the events, because it
will create a huge number of pending events that exhausting the memory.

Fortunately, some watch events could be ignored, depending on its
handler callback.  For example, if the callback has interest in only one
single path, the watch wouldn't want multiple pending events.  Or, some
watches could ignore events to same path.

To let such watches to volutarily help avoiding the memory pressure
situation, this commit introduces new watch callback, 'will_handle'.  If
it is not NULL, it will be called for each new event just before
enqueuing it.  Then, if the callback returns false, the event will be
discarded.  No watch is using the callback for now, though.

This is part of XSA-349

Cc: stable@vger.kernel.org
Signed-off-by: SeongJae Park 
Reported-by: Michael Kurth 
Reported-by: Pawel Wieczorkiewicz 
Reviewed-by: Juergen Gross 
Signed-off-by: Juergen Gross 
Signed-off-by: Greg Kroah-Hartman

seq_buf: Avoid type mismatch for seq_buf_init

2020-12-29T12:42:39+00:00

[ Upstream commit d9a9280a0d0ae51dc1d4142138b99242b7ec8ac6 ]

Building with W=2 prints a number of warnings for one function that
has a pointer type mismatch:

linux/seq_buf.h: In function 'seq_buf_init':
linux/seq_buf.h:35:12: warning: pointer targets in assignment from 'unsigned char *' to 'char *' differ in signedness [-Wpointer-sign]

Change the type in the function prototype according to the type in
the structure.

Link: https://lkml.kernel.org/r/20201026161108.3707783-1-arnd@kernel.org

Fixes: 9a7777935c34 ("tracing: Convert seq_buf fields to be like seq_file fields")
Reviewed-by: Cezary Rojewski 
Signed-off-by: Arnd Bergmann 
Signed-off-by: Steven Rostedt (VMware) 
Signed-off-by: Sasha Levin

spi: Introduce device-managed SPI controller allocation

2020-12-11T12:36:45+00:00

[ Upstream commit 5e844cc37a5cbaa460e68f9a989d321d63088a89 ]

SPI driver probing currently comprises two steps, whereas removal
comprises only one step:

    spi_alloc_master()
    spi_register_master()

    spi_unregister_master()

That's because spi_unregister_master() calls device_unregister()
instead of device_del(), thereby releasing the reference on the
spi_master which was obtained by spi_alloc_master().

An SPI driver's private data is contained in the same memory allocation
as the spi_master struct.  Thus, once spi_unregister_master() has been
called, the private data is inaccessible.  But some drivers need to
access it after spi_unregister_master() to perform further teardown
steps.

Introduce devm_spi_alloc_master(), which releases a reference on the
spi_master struct only after the driver has unbound, thereby keeping the
memory allocation accessible.  Change spi_unregister_master() to not
release a reference if the spi_master was allocated by the new devm
function.

The present commit is small enough to be backportable to stable.
It allows fixing drivers which use the private data in their ->remove()
hook after it's been freed.  It also allows fixing drivers which neglect
to release a reference on the spi_master in the probe error path.

Long-term, most SPI drivers shall be moved over to the devm function
introduced herein.  The few that can't shall be changed in a treewide
commit to explicitly release the last reference on the master.
That commit shall amend spi_unregister_master() to no longer release
a reference, thereby completing the migration.

As a result, the behaviour will be less surprising and more consistent
with subsystems such as IIO, which also includes the private data in the
allocation of the generic iio_dev struct, but calls device_del() in
iio_device_unregister().

Signed-off-by: Lukas Wunner 
Link: https://lore.kernel.org/r/272bae2ef08abd21388c98e23729886663d19192.1605121038.git.lukas@wunner.de
Signed-off-by: Mark Brown 
Signed-off-by: Greg Kroah-Hartman