linux-stable.git/scripts/kallsyms.c, branch v6.1.2

Merge tag 'kbuild-v6.1' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild

2022-10-10T19:00:45+00:00

Pull Kbuild updates from Masahiro Yamada:

- Remove potentially incomplete targets when Kbuid is interrupted by
SIGINT etc in case GNU Make may miss to do that when stderr is piped
to another program.

- Rewrite the single target build so it works more correctly.

- Fix rpm-pkg builds with V=1.

- List top-level subdirectories in ./Kbuild.

- Ignore auto-generated __kstrtab_* and __kstrtabns_* symbols in
kallsyms.

- Avoid two different modules in lib/zstd/ having shared code, which
potentially causes building the common code as build-in and modular
back-and-forth.

- Unify two modpost invocations to optimize the build process.

- Remove head-y syntax in favor of linker scripts for placing
particular sections in the head of vmlinux.

- Bump the minimal GNU Make version to 3.82.

- Clean up misc Makefiles and scripts.

* tag 'kbuild-v6.1' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (41 commits)
docs: bump minimal GNU Make version to 3.82
ia64: simplify esi object addition in Makefile
Revert "kbuild: Check if linker supports the -X option"
kbuild: rebuild .vmlinux.export.o when its prerequisite is updated
kbuild: move modules.builtin(.modinfo) rules to Makefile.vmlinux_o
zstd: Fixing mixed module-builtin objects
kallsyms: ignore __kstrtab_* and __kstrtabns_* symbols
kallsyms: take the input file instead of reading stdin
kallsyms: drop duplicated ignore patterns from kallsyms.c
kbuild: reuse mksysmap output for kallsyms
mksysmap: update comment about __crc_*
kbuild: remove head-y syntax
kbuild: use obj-y instead extra-y for objects placed at the head
kbuild: hide error checker logs for V=1 builds
kbuild: re-run modpost when it is updated
kbuild: unify two modpost invocations
kbuild: move vmlinux.o rule to the top Makefile
kbuild: move .vmlinux.objs rule to Makefile.modpost
kbuild: list sub-directories in ./Kbuild
Makefile.compiler: replace cc-ifversion with compiler-specific macros
...

Merge tag 'kcfi-v6.1-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux

2022-10-04T00:11:07+00:00

Pull kcfi updates from Kees Cook:
 "This replaces the prior support for Clang's standard Control Flow
  Integrity (CFI) instrumentation, which has required a lot of special
  conditions (e.g. LTO) and work-arounds.

  The new implementation ("Kernel CFI") is specific to C, directly
  designed for the Linux kernel, and takes advantage of architectural
  features like x86's IBT. This series retains arm64 support and adds
  x86 support.

  GCC support is expected in the future[1], and additional "generic"
  architectural support is expected soon[2].

  Summary:

   - treewide: Remove old CFI support details

   - arm64: Replace Clang CFI support with Clang KCFI support

   - x86: Introduce Clang KCFI support"

Link: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=107048 [1]
Link: https://github.com/samitolvanen/llvm-project/commits/kcfi_generic [2]

* tag 'kcfi-v6.1-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux: (22 commits)
  x86: Add support for CONFIG_CFI_CLANG
  x86/purgatory: Disable CFI
  x86: Add types to indirectly called assembly functions
  x86/tools/relocs: Ignore __kcfi_typeid_ relocations
  kallsyms: Drop CONFIG_CFI_CLANG workarounds
  objtool: Disable CFI warnings
  objtool: Preserve special st_shndx indexes in elf_update_symbol
  treewide: Drop __cficanonical
  treewide: Drop WARN_ON_FUNCTION_MISMATCH
  treewide: Drop function_nocfi
  init: Drop __nocfi from __init
  arm64: Drop unneeded __nocfi attributes
  arm64: Add CFI error handling
  arm64: Add types to indirect called assembly functions
  psci: Fix the function type for psci_initcall_t
  lkdtm: Emit an indirect call for CFI tests
  cfi: Add type helper macros
  cfi: Switch to -fsanitize=kcfi
  cfi: Drop __CFI_ADDRESSABLE
  cfi: Remove CONFIG_CFI_CLANG_SHADOW
  ...

kallsyms: take the input file instead of reading stdin

2022-10-02T09:06:05+00:00

This gets rid of the pipe operator connected with 'cat'.

Also use getopt_long() to parse the command line.

Signed-off-by: Masahiro Yamada

kallsyms: drop duplicated ignore patterns from kallsyms.c

2022-10-02T09:06:05+00:00

Now that kallsyms.c parses the output from mksysmap, some symbols have
already been dropped.

Move comments to scripts/mksysmap. Also, make the grep command readable.

Signed-off-by: Masahiro Yamada

kallsyms: increase maximum kernel symbol length to 512

2022-09-28T06:56:25+00:00

Rust symbols can become quite long due to namespacing introduced
by modules, types, traits, generics, etc. For instance,
the following code:

    pub mod my_module {
        pub struct MyType;
        pub struct MyGenericType(T);

        pub trait MyTrait {
            fn my_method() -> u32;
        }

        impl MyTrait for MyGenericType {
            fn my_method() -> u32 {
                42
            }
        }
    }

generates a symbol of length 96 when using the upcoming v0 mangling scheme:

    _RNvXNtCshGpAVYOtgW1_7example9my_moduleINtB2_13MyGenericTypeNtB2_6MyTypeENtB2_7MyTrait9my_method

At the moment, Rust symbols may reach up to 300 in length.
Setting 512 as the maximum seems like a reasonable choice to
keep some headroom.

Reviewed-by: Kees Cook 
Reviewed-by: Petr Mladek 
Reviewed-by: Greg Kroah-Hartman 
Co-developed-by: Alex Gaynor 
Signed-off-by: Alex Gaynor 
Co-developed-by: Wedson Almeida Filho 
Signed-off-by: Wedson Almeida Filho 
Co-developed-by: Gary Guo 
Signed-off-by: Gary Guo 
Co-developed-by: Boqun Feng 
Signed-off-by: Boqun Feng 
Signed-off-by: Miguel Ojeda

kallsyms: support "big" kernel symbols

2022-09-28T06:56:08+00:00

Rust symbols can become quite long due to namespacing introduced
by modules, types, traits, generics, etc.

Increasing to 255 is not enough in some cases, therefore
introduce longer lengths to the symbol table.

In order to avoid increasing all lengths to 2 bytes (since most
of them are small, including many Rust ones), use ULEB128 to
keep smaller symbols in 1 byte, with the rest in 2 bytes.

Reviewed-by: Kees Cook 
Reviewed-by: Greg Kroah-Hartman 
Co-developed-by: Alex Gaynor 
Signed-off-by: Alex Gaynor 
Co-developed-by: Wedson Almeida Filho 
Signed-off-by: Wedson Almeida Filho 
Co-developed-by: Gary Guo 
Signed-off-by: Gary Guo 
Co-developed-by: Boqun Feng 
Signed-off-by: Boqun Feng 
Co-developed-by: Matthew Wilcox 
Signed-off-by: Matthew Wilcox 
Signed-off-by: Miguel Ojeda

kallsyms: add static relationship between `KSYM_NAME_LEN{,_BUFFER}`

2022-09-28T06:55:08+00:00

This adds a static assert to ensure `KSYM_NAME_LEN_BUFFER`
gets updated when `KSYM_NAME_LEN` changes.

The relationship used is one that keeps the new size (512+1)
close to the original buffer size (500).

Reviewed-by: Greg Kroah-Hartman 
Co-developed-by: Boqun Feng 
Signed-off-by: Boqun Feng 
Signed-off-by: Miguel Ojeda

kallsyms: avoid hardcoding buffer size

2022-09-28T06:54:39+00:00

This introduces `KSYM_NAME_LEN_BUFFER` in place of the previously
hardcoded size of the input buffer.

It will also make it easier to update the size in a single place
in a later patch.

Reviewed-by: Kees Cook 
Reviewed-by: Greg Kroah-Hartman 
Signed-off-by: Boqun Feng 
Co-developed-by: Miguel Ojeda 
Signed-off-by: Miguel Ojeda

kallsyms: use `ARRAY_SIZE` instead of hardcoded size

2022-09-28T06:54:17+00:00

This removes one place where the `500` constant is hardcoded.

Reviewed-by: Kees Cook 
Reviewed-by: Geert Stappers 
Reviewed-by: Greg Kroah-Hartman 
Signed-off-by: Boqun Feng 
Co-developed-by: Miguel Ojeda 
Signed-off-by: Miguel Ojeda

scripts/kallsyms: Ignore __kcfi_typeid_

2022-09-26T17:13:12+00:00

The compiler generates __kcfi_typeid_ symbols for annotating assembly
functions with type information. These are constants that can be
referenced in assembly code and are resolved by the linker. Ignore
them in kallsyms.

Signed-off-by: Sami Tolvanen 
Reviewed-by: Kees Cook 
Tested-by: Kees Cook 
Tested-by: Nathan Chancellor 
Acked-by: Peter Zijlstra (Intel) 
Tested-by: Peter Zijlstra (Intel) 
Signed-off-by: Kees Cook 
Link: https://lore.kernel.org/r/20220908215504.3686827-3-samitolvanen@google.com