linux-stable.git/lib, branch v4.19.9

test_firmware: fix error return getting clobbered

2018-12-13T08:16:10+00:00

[ Upstream commit 8bb0a88600f0267cfcc245d34f8c4abe8c282713 ]

In the case where eq->fw->size > PAGE_SIZE the error return rc
is being set to EINVAL however this is being overwritten to
rc = req->fw->size because the error exit path via label 'out' is
not being taken.  Fix this by adding the jump to the error exit
path 'out'.

Detected by CoverityScan, CID#1453465 ("Unused value")

Fixes: c92316bf8e94 ("test_firmware: add batched firmware tests")
Signed-off-by: Colin Ian King 
Signed-off-by: Greg Kroah-Hartman 
Signed-off-by: Sasha Levin

test_hexdump: use memcpy instead of strncpy

2018-12-08T11:59:06+00:00

commit b1286ed7158e9b62787508066283ab0b8850b518 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.

Apparently there was a patch for this floating around earlier, but it
got lost.

Acked-again-by: Andy Shevchenko 
Signed-off-by: Linus Torvalds 
Signed-off-by: Greg Kroah-Hartman

lib/test_kmod.c: fix rmmod double free

2018-12-05T18:32:13+00:00

commit 5618cf031fecda63847cafd1091e7b8bd626cdb1 upstream.

We free the misc device string twice on rmmod; fix this.  Without this
we cannot remove the module without crashing.

Link: http://lkml.kernel.org/r/20181124050500.5257-1-mcgrof@kernel.org
Signed-off-by: Luis Chamberlain 
Reported-by: Randy Dunlap 
Reviewed-by: Andrew Morton 
Cc: 	[4.12+]
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds 
Signed-off-by: Greg Kroah-Hartman

lib/raid6: Fix arm64 test build

2018-11-27T15:13:05+00:00

[ Upstream commit 313a06e636808387822af24c507cba92703568b1 ]

The lib/raid6/test fails to build the neon objects
on arm64 because the correct machine type is 'aarch64'.

Once this is correctly enabled, the neon recovery objects
need to be added to the build.

Reviewed-by: Ard Biesheuvel 
Signed-off-by: Jeremy Linton 
Signed-off-by: Catalin Marinas 
Signed-off-by: Sasha Levin

lib/ubsan.c: don't mark __ubsan_handle_builtin_unreachable as noreturn

2018-11-21T08:19:24+00:00

commit 1c23b4108d716cc848b38532063a8aca4f86add8 upstream.

gcc-8 complains about the prototype for this function:

  lib/ubsan.c:432:1: error: ignoring attribute 'noreturn' in declaration of a built-in function '__ubsan_handle_builtin_unreachable' because it conflicts with attribute 'const' [-Werror=attributes]

This is actually a GCC's bug. In GCC internals
__ubsan_handle_builtin_unreachable() declared with both 'noreturn' and
'const' attributes instead of only 'noreturn':

   https://gcc.gnu.org/bugzilla/show_bug.cgi?id=84210

Workaround this by removing the noreturn attribute.

[aryabinin: add information about GCC bug in changelog]
Link: http://lkml.kernel.org/r/20181107144516.4587-1-aryabinin@virtuozzo.com
Signed-off-by: Arnd Bergmann 
Signed-off-by: Andrey Ryabinin 
Acked-by: Olof Johansson 
Cc: 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds 
Signed-off-by: Greg Kroah-Hartman

locking/lockdep: Fix debug_locks off performance problem

2018-11-13T19:08:20+00:00

[ Upstream commit 9506a7425b094d2f1d9c877ed5a78f416669269b ]

It was found that when debug_locks was turned off because of a problem
found by the lockdep code, the system performance could drop quite
significantly when the lock_stat code was also configured into the
kernel. For instance, parallel kernel build time on a 4-socket x86-64
server nearly doubled.

Further analysis into the cause of the slowdown traced back to the
frequent call to debug_locks_off() from the __lock_acquired() function
probably due to some inconsistent lockdep states with debug_locks
off. The debug_locks_off() function did an unconditional atomic xchg
to write a 0 value into debug_locks which had already been set to 0.
This led to severe cacheline contention in the cacheline that held
debug_locks.  As debug_locks is being referenced in quite a few different
places in the kernel, this greatly slow down the system performance.

To prevent that trashing of debug_locks cacheline, lock_acquired()
and lock_contended() now checks the state of debug_locks before
proceeding. The debug_locks_off() function is also modified to check
debug_locks before calling __debug_locks_off().

Signed-off-by: Waiman Long 
Cc: Andrew Morton 
Cc: Linus Torvalds 
Cc: Paul E. McKenney 
Cc: Peter Zijlstra 
Cc: Thomas Gleixner 
Cc: Will Deacon 
Link: http://lkml.kernel.org/r/1539913518-15598-1-git-send-email-longman@redhat.com
Signed-off-by: Ingo Molnar 
Signed-off-by: Sasha Levin 
Signed-off-by: Greg Kroah-Hartman

test_ida: Fix lockdep warning

2018-10-15T20:31:29+00:00

The IDA was declared on the stack instead of statically, so lockdep
triggered a warning that it was improperly initialised.

Reported-by: 0day bot
Tested-by: Rong Chen 
Signed-off-by: Matthew Wilcox

Merge tag 'mtd/fixes-for-4.19-rc8' of git://git.infradead.org/linux-mtd

2018-10-12T10:54:26+00:00

Boris writes:
  "mdt: fix for 4.19-rc8

   * Fix a stack overflow in lib/bch.c"

* tag 'mtd/fixes-for-4.19-rc8' of git://git.infradead.org/linux-mtd:
  lib/bch: fix possible stack overrun

lib/bch: fix possible stack overrun

2018-10-12T07:17:46+00:00

The previous patch introduced very large kernel stack usage and a Makefile
change to hide the warning about it.

From what I can tell, a number of things went wrong here:

- The BCH_MAX_T constant was set to the maximum value for 'n',
  not the maximum for 't', which is much smaller.

- The stack usage is actually larger than the entire kernel stack
  on some architectures that can use 4KB stacks (m68k, sh, c6x), which
  leads to an immediate overrun.

- The justification in the patch description claimed that nothing
  changed, however that is not the case even without the two points above:
  the configuration is machine specific, and most boards  never use the
  maximum BCH_ECC_WORDS() length but instead have something much smaller.
  That maximum would only apply to machines that use both the maximum
  block size and the maximum ECC strength.

The largest value for 't' that I could find is '32', which in turn leads
to a 60 byte array instead of 2048 bytes. Making it '64' for future
extension seems also worthwhile, with 120 bytes for the array. Anything
larger won't fit into the OOB area on NAND flash.

With that changed, the warning can be enabled again.

Only linux-4.19+ contains the breakage, so this is only needed
as a stable backport if it does not make it into the release.

Fixes: 02361bc77888 ("lib/bch: Remove VLA usage")
Reported-by: Ard Biesheuvel 
Cc: stable@vger.kernel.org
Signed-off-by: Arnd Bergmann 
Signed-off-by: Boris Brezillon

Merge tag 'trace-v4.19-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

2018-10-10T20:09:44+00:00

Steven writes:
  "vsprint fix:

   It was reported that trace_printk() was not reporting properly
   values that came after a dereference pointer.

   trace_printk() utilizes vbin_printf() and bstr_printf() to keep the
   overhead of tracing down. vbin_printf() does not do any conversions
   and just stors the string format and the raw arguments into the
   buffer. bstr_printf() is used to read the buffer and does the
   conversions to complete the printf() output.

   This can be troublesome with dereferenced pointers because the
   reference may be different from the time vbin_printf() is called to
   the time bstr_printf() is called. To fix this, a prior commit changed
   vbin_printf() to convert dereferenced pointers into strings and load
   the converted string into the buffer. But the change to bstr_printf()
   had an off-by-one error and didn't account for the nul character at
   the end of the string and this corrupted the rest of the values in
   the format that came after a dereferenced pointer."

* tag 'trace-v4.19-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  vsprintf: Fix off-by-one bug in bstr_printf() processing dereferenced pointers