| Message ID | 20210216173305.2500-1-tklauser@distanz.ch (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | riscv: Disable KSAN_SANITIZE for vDSO | expand |
On Tue, Feb 16, 2021 at 6:33 PM Tobias Klauser <tklauser@distanz.ch> wrote: > > Dmitry Vyukov reports: > > I've localized one issue with riscv/KASAN: > > KASAN breaks VDSO and that's I think the root cause of weird faults I > > saw earlier. The following patch fixes it. > > Could somebody please upstream this fix? I don't know how to add/run > > tests for this. > > Verified the fix on a kernel with KASAN enabled using vDSO selftests. > > Link: https://lore.kernel.org/lkml/CACT4Y+ZNJBnkKHXUf=tm_yuowvZvHwN=0rmJ=7J+xFd+9r_6pQ@mail.gmail.com/ > Cc: Dmitry Vyukov <dvyukov@google.com> > Tested-by: Tobias Klauser <tklauser@distanz.ch> > Signed-off-by: Tobias Klauser <tklauser@distanz.ch> Thanks for the quick fix! Tested-by: Dmitry Vyukov <dvyukov@google.com> > --- > arch/riscv/kernel/vdso/Makefile | 3 ++- > 1 file changed, 2 insertions(+), 1 deletion(-) > > diff --git a/arch/riscv/kernel/vdso/Makefile b/arch/riscv/kernel/vdso/Makefile > index 0cfd6da784f8..71a315e73cbe 100644 > --- a/arch/riscv/kernel/vdso/Makefile > +++ b/arch/riscv/kernel/vdso/Makefile > @@ -32,9 +32,10 @@ CPPFLAGS_vdso.lds += -P -C -U$(ARCH) > # Disable -pg to prevent insert call site > CFLAGS_REMOVE_vgettimeofday.o = $(CC_FLAGS_FTRACE) -Os > > -# Disable gcov profiling for VDSO code > +# Disable profiling and instrumentation for VDSO code > GCOV_PROFILE := n > KCOV_INSTRUMENT := n > +KASAN_SANITIZE := n > > # Force dependency > $(obj)/vdso.o: $(obj)/vdso.so > -- > 2.30.0 >
On Tue, 16 Feb 2021 09:33:05 PST (-0800), tklauser@distanz.ch wrote: > Dmitry Vyukov reports: >> I've localized one issue with riscv/KASAN: >> KASAN breaks VDSO and that's I think the root cause of weird faults I >> saw earlier. The following patch fixes it. >> Could somebody please upstream this fix? I don't know how to add/run >> tests for this. > > Verified the fix on a kernel with KASAN enabled using vDSO selftests. > > Link: https://lore.kernel.org/lkml/CACT4Y+ZNJBnkKHXUf=tm_yuowvZvHwN=0rmJ=7J+xFd+9r_6pQ@mail.gmail.com/ > Cc: Dmitry Vyukov <dvyukov@google.com> > Tested-by: Tobias Klauser <tklauser@distanz.ch> > Signed-off-by: Tobias Klauser <tklauser@distanz.ch> > --- > arch/riscv/kernel/vdso/Makefile | 3 ++- > 1 file changed, 2 insertions(+), 1 deletion(-) > > diff --git a/arch/riscv/kernel/vdso/Makefile b/arch/riscv/kernel/vdso/Makefile > index 0cfd6da784f8..71a315e73cbe 100644 > --- a/arch/riscv/kernel/vdso/Makefile > +++ b/arch/riscv/kernel/vdso/Makefile > @@ -32,9 +32,10 @@ CPPFLAGS_vdso.lds += -P -C -U$(ARCH) > # Disable -pg to prevent insert call site > CFLAGS_REMOVE_vgettimeofday.o = $(CC_FLAGS_FTRACE) -Os > > -# Disable gcov profiling for VDSO code > +# Disable profiling and instrumentation for VDSO code > GCOV_PROFILE := n > KCOV_INSTRUMENT := n > +KASAN_SANITIZE := n > > # Force dependency > $(obj)/vdso.o: $(obj)/vdso.so This seems reasonable. Building the VDSO with asan results in a bunch of PLT entries for the VDSO stubs. I don't see a sane way to resolve those, and it looks like this is what everyone else is doing. That said, the commit text is a bit funny so I've written one of my own. This is on for-next, as it's still the merge window. Let me know if the text doesn't make sense. Thanks!
On 2021-02-19 at 08:15:34 +0100, Palmer Dabbelt <palmer@dabbelt.com> wrote: > On Tue, 16 Feb 2021 09:33:05 PST (-0800), tklauser@distanz.ch wrote: > > Dmitry Vyukov reports: > > > I've localized one issue with riscv/KASAN: > > > KASAN breaks VDSO and that's I think the root cause of weird faults I > > > saw earlier. The following patch fixes it. > > > Could somebody please upstream this fix? I don't know how to add/run > > > tests for this. > > > > Verified the fix on a kernel with KASAN enabled using vDSO selftests. > > > > Link: https://lore.kernel.org/lkml/CACT4Y+ZNJBnkKHXUf=tm_yuowvZvHwN=0rmJ=7J+xFd+9r_6pQ@mail.gmail.com/ > > Cc: Dmitry Vyukov <dvyukov@google.com> > > Tested-by: Tobias Klauser <tklauser@distanz.ch> > > Signed-off-by: Tobias Klauser <tklauser@distanz.ch> > > --- > > arch/riscv/kernel/vdso/Makefile | 3 ++- > > 1 file changed, 2 insertions(+), 1 deletion(-) > > > > diff --git a/arch/riscv/kernel/vdso/Makefile b/arch/riscv/kernel/vdso/Makefile > > index 0cfd6da784f8..71a315e73cbe 100644 > > --- a/arch/riscv/kernel/vdso/Makefile > > +++ b/arch/riscv/kernel/vdso/Makefile > > @@ -32,9 +32,10 @@ CPPFLAGS_vdso.lds += -P -C -U$(ARCH) > > # Disable -pg to prevent insert call site > > CFLAGS_REMOVE_vgettimeofday.o = $(CC_FLAGS_FTRACE) -Os > > > > -# Disable gcov profiling for VDSO code > > +# Disable profiling and instrumentation for VDSO code > > GCOV_PROFILE := n > > KCOV_INSTRUMENT := n > > +KASAN_SANITIZE := n > > > > # Force dependency > > $(obj)/vdso.o: $(obj)/vdso.so > > This seems reasonable. Building the VDSO with asan results in a bunch of PLT > entries for the VDSO stubs. I don't see a sane way to resolve those, and it > looks like this is what everyone else is doing. > > That said, the commit text is a bit funny so I've written one of my own. This > is on for-next, as it's still the merge window. Let me know if the text > doesn't make sense. Thanks for fixing up the commit message and adding the Fixes line. Makes sense to me.
diff --git a/arch/riscv/kernel/vdso/Makefile b/arch/riscv/kernel/vdso/Makefile index 0cfd6da784f8..71a315e73cbe 100644 --- a/arch/riscv/kernel/vdso/Makefile +++ b/arch/riscv/kernel/vdso/Makefile @@ -32,9 +32,10 @@ CPPFLAGS_vdso.lds += -P -C -U$(ARCH) # Disable -pg to prevent insert call site CFLAGS_REMOVE_vgettimeofday.o = $(CC_FLAGS_FTRACE) -Os -# Disable gcov profiling for VDSO code +# Disable profiling and instrumentation for VDSO code GCOV_PROFILE := n KCOV_INSTRUMENT := n +KASAN_SANITIZE := n # Force dependency $(obj)/vdso.o: $(obj)/vdso.so