linux.git/scripts/mod/modpost.c, branch v4.14.145

kbuild: modversions: Fix relative CRC byte order interpretation

2019-04-03T04:25:17+00:00

commit 54a7151b1496cddbb7a83546b7998103e98edc88 upstream.

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

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

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

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

Fixes: 56067812d5b0 ("kbuild: modversions: add infrastructure for emitting relative CRCs")
Signed-off-by: Fredrik Noring 
Cc: stable@vger.kernel.org
Signed-off-by: Masahiro Yamada 
Signed-off-by: Greg Kroah-Hartman

modpost: validate symbol names also in find_elf_symbol

2019-02-12T18:45:59+00:00

[ Upstream commit 5818c683a619c534c113e1f66d24f636defc29bc ]

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 
Signed-off-by: Masahiro Yamada 
Signed-off-by: Sasha Levin

x86, modpost: Replace last remnants of RETPOLINE with CONFIG_RETPOLINE

2019-01-16T21:07:10+00:00

commit e4f358916d528d479c3c12bd2fd03f2d5a576380 upstream.

Commit

  4cd24de3a098 ("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: 4cd24de3a098 ("x86/retpoline: Make CONFIG_RETPOLINE depend on compiler support")
Signed-off-by: WANG Chao 
Signed-off-by: Borislav Petkov 
Reviewed-by: Zhenzhong Duan 
Reviewed-by: Masahiro Yamada 
Cc: "H. Peter Anvin" 
Cc: Andi Kleen 
Cc: Andrew Morton 
Cc: Andy Lutomirski 
Cc: Arnd Bergmann 
Cc: Daniel Borkmann 
Cc: David Woodhouse 
Cc: Geert Uytterhoeven 
Cc: Jessica Yu 
Cc: Jiri Kosina 
Cc: Kees Cook 
Cc: Konrad Rzeszutek Wilk 
Cc: Luc Van Oostenryck 
Cc: Michal Marek 
Cc: Miguel Ojeda 
Cc: Peter Zijlstra 
Cc: Tim Chen 
Cc: Vasily Gorbik 
Cc: linux-kbuild@vger.kernel.org
Cc: srinivas.eeda@oracle.com
Cc: stable 
Cc: x86-ml 
Link: https://lkml.kernel.org/r/20181210163725.95977-1-chao.wang@ucloud.cn
Signed-off-by: Greg Kroah-Hartman

scripts: modpost: check memory allocation results

2018-09-15T07:45:27+00:00

[ Upstream commit 1f3aa9002dc6a0d59a4b599b4fc8f01cf43ef014 ]

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 
Cc: Yuexing Wang 
Signed-off-by: Masahiro Yamada 
Signed-off-by: Sasha Levin 
Signed-off-by: Greg Kroah-Hartman

module/retpoline: Warn about missing retpoline in module

2018-02-07T19:12:18+00:00

commit caf7501a1b4ec964190f31f9c3f163de252273b8

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 
Signed-off-by: Thomas Gleixner 
Cc: David Woodhouse 
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

Merge tag 'modules-for-v4.14' of git://git.kernel.org/pub/scm/linux/kernel/git/jeyu/linux

2017-09-13T18:28:19+00:00

Pull modules updates from Jessica Yu:
 "Summary of modules changes for the 4.14 merge window:

   - minor code cleanups and fixes

   - modpost: avoid building modules that have names that exceed the
     size of the name field in struct module"

* tag 'modules-for-v4.14' of git://git.kernel.org/pub/scm/linux/kernel/git/jeyu/linux:
  module: Remove const attribute from alias for MODULE_DEVICE_TABLE
  module: fix ddebug_remove_module()
  modpost: abort if module name is too long

modpost: simplify sec_name()

2017-09-07T00:27:24+00:00

There is code duplication between sec_name() and sech_name().  Simplify
sec_name() by re-using sech_name().  Also, move them up to remove the
forward declaration of sec_name().

Link: http://lkml.kernel.org/r/1502248721-22009-1-git-send-email-yamada.masahiro@socionext.com
Signed-off-by: Masahiro Yamada 
Reviewed-by: Kees Cook 
Cc: Nicholas Piggin 
Cc: Jessica Yu 
Cc: Chris Metcalf 
Cc: Heinrich Schuchardt 
Cc: Ingo Molnar 
Cc: Ard Biesheuvel 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

modpost: abort if module name is too long

2017-07-25T13:08:19+00:00

Module name has a limited length, but currently the build system
allows the build finishing even if the module name is too long.

  CC      /root/kprobe_example/abcdefghijklmnopqrstuvwxyzabcdefghijklmnopqrstuvwxyzabcdefghijklmnopqrstuvwxyz.mod.o
 /root/kprobe_example/abcdefghijklmnopqrstuvwxyzabcdefghijklmnopqrstuvwxyzabcdefghijklmnopqrstuvwxyz.mod.c:9:2:
 warning: initializer-string for array of chars is too long [enabled by default]
  .name = KBUILD_MODNAME,
  ^

but it's merely a warning.

This patch adds the check of the module name length in modpost and stops
the build properly.

Signed-off-by: Wanlong Gao 
Signed-off-by: Jessica Yu

module: Add module name to modinfo

2017-05-23T21:08:31+00:00

Accessing the mod structure (e.g. for mod->name) prior to having completed
check_modstruct_version() can result in writing garbage to the error logs
if the layout of the mod structure loaded from disk doesn't match the
running kernel's mod structure layout. This kind of mismatch will become
much more likely if a kernel is built with different randomization seed
for the struct layout randomization plugin.

Instead, add and use a new modinfo string for logging the module name.

Signed-off-by: Kees Cook 
Signed-off-by: Jessica Yu

objtool, modules: Discard objtool annotation sections for modules

2017-03-01T19:32:25+00:00

The '__unreachable' and '__func_stack_frame_non_standard' sections are
only used at compile time.  They're discarded for vmlinux but they
should also be discarded for modules.

Since this is a recurring pattern, prefix the section names with
".discard.".  It's a nice convention and vmlinux.lds.h already discards
such sections.

Also remove the 'a' (allocatable) flag from the __unreachable section
since it doesn't make sense for a discarded section.

Suggested-by: Linus Torvalds 
Signed-off-by: Josh Poimboeuf 
Cc: Jessica Yu 
Cc: Peter Zijlstra 
Cc: Thomas Gleixner 
Fixes: d1091c7fa3d5 ("objtool: Improve detection of BUG() and other dead ends")
Link: http://lkml.kernel.org/r/20170301180444.lhd53c5tibc4ns77@treble
Signed-off-by: Ingo Molnar