lib/ubsan: add type mismatch handler for new GCC/Clang
authorAndrey Ryabinin <aryabinin@virtuozzo.com>
Tue, 6 Feb 2018 23:40:42 +0000 (15:40 -0800)
committerLinus Torvalds <torvalds@linux-foundation.org>
Wed, 7 Feb 2018 02:32:46 +0000 (18:32 -0800)
commit42440c1f9911b4b7b8ba3dc4e90c1197bc561211
treeb89beb05c6a0a42c7e289a8050ba7797aae6a586
parentb8fe1120b4ba342b4f156d24e952d6e686b20298
lib/ubsan: add type mismatch handler for new GCC/Clang

UBSAN=y fails to build with new GCC/clang:

    arch/x86/kernel/head64.o: In function `sanitize_boot_params':
    arch/x86/include/asm/bootparam_utils.h:37: undefined reference to `__ubsan_handle_type_mismatch_v1'

because Clang and GCC 8 slightly changed ABI for 'type mismatch' errors.
Compiler now uses new __ubsan_handle_type_mismatch_v1() function with
slightly modified 'struct type_mismatch_data'.

Let's add new 'struct type_mismatch_data_common' which is independent from
compiler's layout of 'struct type_mismatch_data'.  And make
__ubsan_handle_type_mismatch[_v1]() functions transform compiler-dependent
type mismatch data to our internal representation.  This way, we can
support both old and new compilers with minimal amount of change.

Link: http://lkml.kernel.org/r/20180119152853.16806-1-aryabinin@virtuozzo.com
Signed-off-by: Andrey Ryabinin <aryabinin@virtuozzo.com>
Reported-by: Sodagudi Prasad <psodagud@codeaurora.org>
Cc: <stable@vger.kernel.org> [4.5+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
lib/ubsan.c
lib/ubsan.h