Re: [PATCH mips-fixes] MIPS: compressed: fix build with enabled UBSAN

From: Thomas Bogendoerfer
Date: Tue Feb 09 2021 - 07:42:31 EST


On Mon, Feb 08, 2021 at 12:37:42PM +0000, Alexander Lobakin wrote:
> Commit 1e35918ad9d1 ("MIPS: Enable Undefined Behavior Sanitizer
> UBSAN") added a possibility to build the entire kernel with UBSAN
> instrumentation for MIPS, with the exception for VDSO.
> However, self-extracting head wasn't been added to exceptions, so
> this occurs:
>
> mips-alpine-linux-musl-ld: arch/mips/boot/compressed/decompress.o:
> in function `FSE_buildDTable_wksp':
> decompress.c:(.text.FSE_buildDTable_wksp+0x278): undefined reference
> to `__ubsan_handle_shift_out_of_bounds'
> mips-alpine-linux-musl-ld: decompress.c:(.text.FSE_buildDTable_wksp+0x2a8):
> undefined reference to `__ubsan_handle_shift_out_of_bounds'
> mips-alpine-linux-musl-ld: decompress.c:(.text.FSE_buildDTable_wksp+0x2c4):
> undefined reference to `__ubsan_handle_shift_out_of_bounds'
> mips-alpine-linux-musl-ld: arch/mips/boot/compressed/decompress.o:
> decompress.c:(.text.FSE_buildDTable_raw+0x9c): more undefined references
> to `__ubsan_handle_shift_out_of_bounds' follow
>
> Add UBSAN_SANITIZE := n to mips/boot/compressed/Makefile to exclude
> it from instrumentation scope and fix this issue.
>
> Fixes: 1e35918ad9d1 ("MIPS: Enable Undefined Behavior Sanitizer UBSAN")
> Cc: stable@xxxxxxxxxxxxxxx # 5.0+
> Signed-off-by: Alexander Lobakin <alobakin@xxxxx>
> ---
> arch/mips/boot/compressed/Makefile | 1 +
> 1 file changed, 1 insertion(+)

applied to mips-next.

Thomas.

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