forked from luck/tmp_suning_uos_patched
277a10850f
In order to do kernel builds with the bounds checker individually available, introduce CONFIG_UBSAN_BOUNDS, with the remaining options under CONFIG_UBSAN_MISC. For example, using this, we can start to expand the coverage syzkaller is providing. Right now, all of UBSan is disabled for syzbot builds because taken as a whole, it is too noisy. This will let us focus on one feature at a time. For the bounds checker specifically, this provides a mechanism to eliminate an entire class of array overflows with close to zero performance overhead (I cannot measure a difference). In my (mostly) defconfig, enabling bounds checking adds ~4200 checks to the kernel. Performance changes are in the noise, likely due to the branch predictors optimizing for the non-fail path. Some notes on the bounds checker: - it does not instrument {mem,str}*()-family functions, it only instruments direct indexed accesses (e.g. "foo[i]"). Dealing with the {mem,str}*()-family functions is a work-in-progress around CONFIG_FORTIFY_SOURCE[1]. - it ignores flexible array members, including the very old single byte (e.g. "int foo[1];") declarations. (Note that GCC's implementation appears to ignore _all_ trailing arrays, but Clang only ignores empty, 0, and 1 byte arrays[2].) [1] https://github.com/KSPP/linux/issues/6 [2] https://gcc.gnu.org/bugzilla/show_bug.cgi?id=92589 Suggested-by: Elena Petrova <lenaptr@google.com> Signed-off-by: Kees Cook <keescook@chromium.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Andrey Ryabinin <aryabinin@virtuozzo.com> Acked-by: Dmitry Vyukov <dvyukov@google.com> Cc: Alexander Potapenko <glider@google.com> Cc: Andrey Konovalov <andreyknvl@google.com> Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Dan Carpenter <dan.carpenter@oracle.com> Cc: "Gustavo A. R. Silva" <gustavo@embeddedor.com> Link: http://lkml.kernel.org/r/20200227193516.32566-3-keescook@chromium.org Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
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.. | ||
atomic | ||
basic | ||
coccinelle | ||
dtc | ||
gcc-plugins | ||
gdb | ||
genksyms | ||
kconfig | ||
ksymoops | ||
mod | ||
package | ||
selinux | ||
tracing | ||
.gitignore | ||
adjust_autoksyms.sh | ||
asn1_compiler.c | ||
bin2c.c | ||
bloat-o-meter | ||
bootgraph.pl | ||
bpf_helpers_doc.py | ||
cc-can-link.sh | ||
check_extable.sh | ||
check-sysctl-docs | ||
checkincludes.pl | ||
checkkconfigsymbols.py | ||
checkpatch.pl | ||
checkstack.pl | ||
checksyscalls.sh | ||
checkversion.pl | ||
clang-version.sh | ||
cleanfile | ||
cleanpatch | ||
coccicheck | ||
config | ||
const_structs.checkpatch | ||
decode_stacktrace.sh | ||
decodecode | ||
depmod.sh | ||
diffconfig | ||
documentation-file-ref-check | ||
export_report.pl | ||
extract_xc3028.pl | ||
extract-cert.c | ||
extract-ikconfig | ||
extract-module-sig.pl | ||
extract-sys-certs.pl | ||
extract-vmlinux | ||
faddr2line | ||
file-size.sh | ||
find-unused-docs.sh | ||
gcc-goto.sh | ||
gcc-ld | ||
gcc-plugin.sh | ||
gcc-version.sh | ||
gcc-x86_32-has-stack-protector.sh | ||
gcc-x86_64-has-stack-protector.sh | ||
gen_autoksyms.sh | ||
gen_compile_commands.py | ||
gen_ksymdeps.sh | ||
get_abi.pl | ||
get_dvb_firmware | ||
get_maintainer.pl | ||
gfp-translate | ||
headerdep.pl | ||
headers_check.pl | ||
headers_install.sh | ||
insert-sys-cert.c | ||
jobserver-exec | ||
kallsyms.c | ||
Kbuild.include | ||
Kconfig.include | ||
kernel-doc | ||
ld-version.sh | ||
leaking_addresses.pl | ||
Lindent | ||
link-vmlinux.sh | ||
Makefile | ||
Makefile.asm-generic | ||
Makefile.build | ||
Makefile.clean | ||
Makefile.dtbinst | ||
Makefile.extrawarn | ||
Makefile.gcc-plugins | ||
Makefile.headersinst | ||
Makefile.host | ||
Makefile.kasan | ||
Makefile.kcov | ||
Makefile.lib | ||
Makefile.modfinal | ||
Makefile.modinst | ||
Makefile.modpost | ||
Makefile.modsign | ||
Makefile.package | ||
Makefile.ubsan | ||
makelst | ||
markup_oops.pl | ||
mkcompile_h | ||
mkmakefile | ||
mksysmap | ||
mkuboot.sh | ||
module-common.lds | ||
modules-check.sh | ||
namespace.pl | ||
nsdeps | ||
objdiff | ||
parse-maintainers.pl | ||
patch-kernel | ||
profile2linkerlist.pl | ||
prune-kernel | ||
recordmcount.c | ||
recordmcount.h | ||
recordmcount.pl | ||
setlocalversion | ||
show_delta | ||
sign-file.c | ||
sorttable.c | ||
sorttable.h | ||
spdxcheck-test.sh | ||
spdxcheck.py | ||
spelling.txt | ||
sphinx-pre-install | ||
split-man.pl | ||
stackdelta | ||
stackusage | ||
subarch.include | ||
tags.sh | ||
tools-support-relr.sh | ||
unifdef.c | ||
ver_linux | ||
xen-hypercalls.sh | ||
xz_wrap.sh |