This is a note to let you know that I've just added the patch titled MIPS: compressed: fix build with enabled UBSAN to the 5.11-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: mips-compressed-fix-build-with-enabled-ubsan.patch and it can be found in the queue-5.11 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From fc4cac4cfc437659ce445c3c47b807e1cc625b66 Mon Sep 17 00:00:00 2001 From: Alexander Lobakin <alobakin@xxxxx> Date: Mon, 8 Feb 2021 12:37:42 +0000 Subject: MIPS: compressed: fix build with enabled UBSAN From: Alexander Lobakin <alobakin@xxxxx> commit fc4cac4cfc437659ce445c3c47b807e1cc625b66 upstream. 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> Signed-off-by: Thomas Bogendoerfer <tsbogend@xxxxxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- arch/mips/boot/compressed/Makefile | 1 + 1 file changed, 1 insertion(+) --- a/arch/mips/boot/compressed/Makefile +++ b/arch/mips/boot/compressed/Makefile @@ -37,6 +37,7 @@ KBUILD_AFLAGS := $(KBUILD_AFLAGS) -D__AS # Prevents link failures: __sanitizer_cov_trace_pc() is not linked in. KCOV_INSTRUMENT := n GCOV_PROFILE := n +UBSAN_SANITIZE := n # decompressor objects (linked with vmlinuz) vmlinuzobjs-y := $(obj)/head.o $(obj)/decompress.o $(obj)/string.o Patches currently in stable-queue which might be from alobakin@xxxxx are queue-5.11/mips-vmlinux.lds.s-add-missing-page_aligned_data-section.patch queue-5.11/mips-compressed-fix-build-with-enabled-ubsan.patch queue-5.11/mips-properly-stop-.eh_frame-generation.patch