linux-toradex.git/kernel/module.c, branch v4.10-rc5

taint/module: Fix problems when out-of-kernel driver defines true or false

2017-01-17T18:56:45+00:00

Commit 7fd8329ba502 ("taint/module: Clean up global and module taint
flags handling") used the key words true and false as character members
of a new struct. These names cause problems when out-of-kernel modules
such as VirtualBox include their own definitions of true and false.

Fixes: 7fd8329ba502 ("taint/module: Clean up global and module taint flags handling")
Signed-off-by: Larry Finger 
Cc: Petr Mladek 
Cc: Jessica Yu 
Cc: Rusty Russell 
Reported-by: Valdis Kletnieks 
Reviewed-by: Petr Mladek 
Acked-by: Rusty Russell 
Signed-off-by: Jessica Yu

Replace with globally

2016-12-24T19:46:01+00:00

This was entirely automated, using the script by Al:

  PATT='^[[:blank:]]*#[[:blank:]]*include[[:blank:]]*'
  sed -i -e "s!$PATT!#include !" \
        $(git grep -l "$PATT"|grep -v ^include/linux/uaccess.h)

to do the replacement at the end of the merge window.

Requested-by: Al Viro 
Signed-off-by: Linus Torvalds

Merge tag 'modules-for-v4.10' of git://git.kernel.org/pub/scm/linux/kernel/git/jeyu/linux

2016-12-15T04:12:43+00:00

Pull modules updates from Jessica Yu:
 "Summary of modules changes for the 4.10 merge window:

   - The rodata= cmdline parameter has been extended to additionally
     apply to module mappings

   - Fix a hard to hit race between module loader error/clean up
     handling and ftrace registration

   - Some code cleanups, notably panic.c and modules code use a unified
     taint_flags table now. This is much cleaner than duplicating the
     taint flag code in modules.c"

* tag 'modules-for-v4.10' of git://git.kernel.org/pub/scm/linux/kernel/git/jeyu/linux:
  module: fix DEBUG_SET_MODULE_RONX typo
  module: extend 'rodata=off' boot cmdline parameter to module mappings
  module: Fix a comment above strong_try_module_get()
  module: When modifying a module's text ignore modules which are going away too
  module: Ensure a module's state is set accordingly during module coming cleanup code
  module: remove trailing whitespace
  taint/module: Clean up global and module taint flags handling
  modpost: free allocated memory

Re-enable CONFIG_MODVERSIONS in a slightly weaker form

2016-11-30T00:01:30+00:00

This enables CONFIG_MODVERSIONS again, but allows for missing symbol CRC
information in order to work around the issue that newer binutils
versions seem to occasionally drop the CRC on the floor.  binutils 2.26
seems to work fine, while binutils 2.27 seems to break MODVERSIONS of
symbols that have been defined in assembler files.

[ We've had random missing CRC's before - it may be an old problem that
  just is now reliably triggered with the weak asm symbols and a new
  version of binutils ]

Some day I really do want to remove MODVERSIONS entirely.  Sadly, today
does not appear to be that day: Debian people apparently do want the
option to enable MODVERSIONS to make it easier to have external modules
across kernel versions, and this seems to be a fairly minimal fix for
the annoying problem.

Cc: Ben Hutchings 
Acked-by: Michal Marek 
Signed-off-by: Linus Torvalds

module: extend 'rodata=off' boot cmdline parameter to module mappings

2016-11-28T00:15:33+00:00

The current "rodata=off" parameter disables read-only kernel mappings
under CONFIG_DEBUG_RODATA:
    commit d2aa1acad22f ("mm/init: Add 'rodata=off' boot cmdline parameter
    to disable read-only kernel mappings")

This patch is a logical extension to module mappings ie. read-only mappings
at module loading can be disabled even if CONFIG_DEBUG_SET_MODULE_RONX
(mainly for debug use). Please note, however, that it only affects RO/RW
permissions, keeping NX set.

This is the first step to make CONFIG_DEBUG_SET_MODULE_RONX mandatory
(always-on) in the future as CONFIG_DEBUG_RODATA on x86 and arm64.

Suggested-by: and Acked-by: Mark Rutland 
Signed-off-by: AKASHI Takahiro 
Reviewed-by: Kees Cook 
Acked-by: Rusty Russell 
Link: http://lkml.kernel.org/r/20161114061505.15238-1-takahiro.akashi@linaro.org
Signed-off-by: Jessica Yu

module: Fix a comment above strong_try_module_get()

2016-11-26T19:18:03+00:00

The comment above strong_try_module_get() function is not true anymore.
Return values changed with commit c9a3ba55bb5d ("module: wait for
dependent modules doing init.").

Signed-off-by: Miroslav Benes 
Link: http://lkml.kernel.org/r/alpine.LNX.2.00.1611161635330.12580@pobox.suse.cz
[jeyu@redhat.com: style fixes to make checkpatch.pl happy]
Signed-off-by: Jessica Yu

module: When modifying a module's text ignore modules which are going away too

2016-11-26T19:18:03+00:00

By default, during the access permission modification of a module's core
and init pages, we only ignore modules that are malformed. Albeit for a
module which is going away, it does not make sense to change its text to
RO since the module should be RW, before deallocation.

This patch makes set_all_modules_text_ro() skip modules which are going
away too.

Signed-off-by: Aaron Tomlin 
Acked-by: Rusty Russell 
Link: http://lkml.kernel.org/r/1477560966-781-1-git-send-email-atomlin@redhat.com
[jeyu@redhat.com: add comment as suggested by Steven Rostedt]
Signed-off-by: Jessica Yu

module: Ensure a module's state is set accordingly during module coming cleanup code

2016-11-26T19:18:02+00:00

In load_module() in the event of an error, for e.g. unknown module
parameter(s) specified we go to perform some module coming clean up
operations. At this point the module is still in a "formed" state
when it is actually going away.

This patch updates the module's state accordingly to ensure anyone on the
module_notify_list waiting for a module going away notification will be
notified accordingly.

Signed-off-by: Aaron Tomlin 
Acked-by: Rusty Russell 
Reviewed-by: Miroslav Benes 
Link: http://lkml.kernel.org/r/1476980293-19062-2-git-send-email-atomlin@redhat.com
Signed-off-by: Jessica Yu

taint/module: Clean up global and module taint flags handling

2016-11-26T19:18:01+00:00

The commit 66cc69e34e86a231 ("Fix: module signature vs tracepoints:
add new TAINT_UNSIGNED_MODULE") updated module_taint_flags() to
potentially print one more character. But it did not increase the
size of the corresponding buffers in m_show() and print_modules().

We have recently done the same mistake when adding a taint flag
for livepatching, see
https://lkml.kernel.org/r/cfba2c823bb984690b73572aaae1db596b54a082.1472137475.git.jpoimboe@redhat.com

Also struct module uses an incompatible type for mod-taints flags.
It survived from the commit 2bc2d61a9638dab670d ("[PATCH] list module
taint flags in Oops/panic"). There was used "int" for the global taint
flags at these times. But only the global tain flags was later changed
to "unsigned long" by the commit 25ddbb18aae33ad2 ("Make the taint
flags reliable").

This patch defines TAINT_FLAGS_COUNT that can be used to create
arrays and buffers of the right size. Note that we could not use
enum because the taint flag indexes are used also in assembly code.

Then it reworks the table that describes the taint flags. The TAINT_*
numbers can be used as the index. Instead, we add information
if the taint flag is also shown per-module.

Finally, it uses "unsigned long", bit operations, and the updated
taint_flags table also for mod->taints.

It is not optimal because only few taint flags can be printed by
module_taint_flags(). But better be on the safe side. IMHO, it is
not worth the optimization and this is a good compromise.

Signed-off-by: Petr Mladek
Link: http://lkml.kernel.org/r/1474458442-21581-1-git-send-email-pmladek@suse.com
[jeyu@redhat.com: fix broken lkml link in changelog]
Signed-off-by: Jessica Yu

livepatch/module: make TAINT_LIVEPATCH module-specific

2016-08-26T12:42:08+00:00

There's no reliable way to determine which module tainted the kernel
with TAINT_LIVEPATCH.  For example, /sys/module//taint
doesn't report it.  Neither does the "mod -t" command in the crash tool.

Make it crystal clear who the guilty party is by associating
TAINT_LIVEPATCH with any module which sets the "livepatch" modinfo
attribute.  The flag will still get set in the kernel like before, but
now it also sets the same flag in mod->taint.

Note that now the taint flag gets set when the module is loaded rather
than when it's enabled.

I also renamed find_livepatch_modinfo() to check_modinfo_livepatch() to
better reflect its purpose: it's basically a livepatch-specific
sub-function of check_modinfo().

Reported-by: Chunyu Hu 
Reviewed-by: Petr Mladek 
Acked-by: Miroslav Benes 
Acked-by: Jessica Yu 
Acked-by: Rusty Russell 
Signed-off-by: Josh Poimboeuf 
Signed-off-by: Jiri Kosina