| Message ID | 20200415221520.2692512-6-nivedita@alum.mit.edu (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | efi: Remove __efistub_global annotation | expand |
On Thu, 16 Apr 2020 at 00:15, Arvind Sankar <nivedita@alum.mit.edu> wrote: > > Add relocation checking for x86 as well to catch non-PC-relative > relocations that require runtime processing, since the EFI stub does not > do any runtime relocation processing. > > This will catch, for example, data relocations created by static > initializers of pointers. > > Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu> > --- > drivers/firmware/efi/libstub/Makefile | 10 +++++----- > 1 file changed, 5 insertions(+), 5 deletions(-) > > diff --git a/drivers/firmware/efi/libstub/Makefile b/drivers/firmware/efi/libstub/Makefile > index 0bb2916eb12b..2aff59812a54 100644 > --- a/drivers/firmware/efi/libstub/Makefile > +++ b/drivers/firmware/efi/libstub/Makefile > @@ -96,6 +96,8 @@ STUBCOPY_RELOC-$(CONFIG_ARM) := R_ARM_ABS > # .bss section here so it's easy to pick out in the linker script. > # > STUBCOPY_FLAGS-$(CONFIG_X86) += --rename-section .bss=.bss.efistub,load,alloc > +STUBCOPY_RELOC-$(CONFIG_X86_32) := 'R_X86_32_(8|16|32)' This should be R_386_xxx > +STUBCOPY_RELOC-$(CONFIG_X86_64) := 'R_X86_64_(8|16|32|32S|64)' > ... and in general, I think we only need the native pointer sized ones, so R_386_32 R_X86_64_64 > $(obj)/%.stub.o: $(obj)/%.o FORCE > $(call if_changed,stubcopy) > @@ -107,16 +109,14 @@ $(obj)/%.stub.o: $(obj)/%.o FORCE > # this time, use objcopy and leave all sections in place. > # > > -cmd_stubrelocs_check-y = /bin/true > - > -cmd_stubrelocs_check-$(CONFIG_EFI_ARMSTUB) = \ > +cmd_stubrelocs_check = \ > $(STRIP) --strip-debug -o $@ $<; \ > - if $(OBJDUMP) -r $@ | grep $(STUBCOPY_RELOC-y); then \ > + if $(OBJDUMP) -r $@ | grep -E $(STUBCOPY_RELOC-y); then \ ... which means we don't need to -E either > echo "$@: absolute symbol references not allowed in the EFI stub" >&2; \ > /bin/false; \ > fi > > quiet_cmd_stubcopy = STUBCPY $@ > cmd_stubcopy = \ > - $(cmd_stubrelocs_check-y); \ > + $(cmd_stubrelocs_check); \ > $(OBJCOPY) $(STUBCOPY_FLAGS-y) $< $@ > -- > 2.24.1 > Could we fold this into the previous x86 patch, and drop the one that splits off the relocation check from stubcpy?
On Thu, Apr 16, 2020 at 09:38:36AM +0200, Ard Biesheuvel wrote: > On Thu, 16 Apr 2020 at 00:15, Arvind Sankar <nivedita@alum.mit.edu> wrote: > > > > Add relocation checking for x86 as well to catch non-PC-relative > > relocations that require runtime processing, since the EFI stub does not > > do any runtime relocation processing. > > > > This will catch, for example, data relocations created by static > > initializers of pointers. > > > > Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu> > > --- > > drivers/firmware/efi/libstub/Makefile | 10 +++++----- > > 1 file changed, 5 insertions(+), 5 deletions(-) > > > > diff --git a/drivers/firmware/efi/libstub/Makefile b/drivers/firmware/efi/libstub/Makefile > > index 0bb2916eb12b..2aff59812a54 100644 > > --- a/drivers/firmware/efi/libstub/Makefile > > +++ b/drivers/firmware/efi/libstub/Makefile > > @@ -96,6 +96,8 @@ STUBCOPY_RELOC-$(CONFIG_ARM) := R_ARM_ABS > > # .bss section here so it's easy to pick out in the linker script. > > # > > STUBCOPY_FLAGS-$(CONFIG_X86) += --rename-section .bss=.bss.efistub,load,alloc > > +STUBCOPY_RELOC-$(CONFIG_X86_32) := 'R_X86_32_(8|16|32)' > > This should be R_386_xxx Oops. I tested 64-bit but not 32-bit. I'll fix. > > > +STUBCOPY_RELOC-$(CONFIG_X86_64) := 'R_X86_64_(8|16|32|32S|64)' > > > > ... and in general, I think we only need the native pointer sized ones, so > > R_386_32 > R_X86_64_64 Ok. > > > $(obj)/%.stub.o: $(obj)/%.o FORCE > > $(call if_changed,stubcopy) > > @@ -107,16 +109,14 @@ $(obj)/%.stub.o: $(obj)/%.o FORCE > > # this time, use objcopy and leave all sections in place. > > # > > > > -cmd_stubrelocs_check-y = /bin/true > > - > > -cmd_stubrelocs_check-$(CONFIG_EFI_ARMSTUB) = \ > > +cmd_stubrelocs_check = \ > > $(STRIP) --strip-debug -o $@ $<; \ > > - if $(OBJDUMP) -r $@ | grep $(STUBCOPY_RELOC-y); then \ > > + if $(OBJDUMP) -r $@ | grep -E $(STUBCOPY_RELOC-y); then \ > > ... which means we don't need to -E either > > > echo "$@: absolute symbol references not allowed in the EFI stub" >&2; \ > > /bin/false; \ > > fi > > > > quiet_cmd_stubcopy = STUBCPY $@ > > cmd_stubcopy = \ > > - $(cmd_stubrelocs_check-y); \ > > + $(cmd_stubrelocs_check); \ > > $(OBJCOPY) $(STUBCOPY_FLAGS-y) $< $@ > > -- > > 2.24.1 > > > > Could we fold this into the previous x86 patch, and drop the one that > splits off the relocation check from stubcpy? Will do.
diff --git a/drivers/firmware/efi/libstub/Makefile b/drivers/firmware/efi/libstub/Makefile index 0bb2916eb12b..2aff59812a54 100644 --- a/drivers/firmware/efi/libstub/Makefile +++ b/drivers/firmware/efi/libstub/Makefile @@ -96,6 +96,8 @@ STUBCOPY_RELOC-$(CONFIG_ARM) := R_ARM_ABS # .bss section here so it's easy to pick out in the linker script. # STUBCOPY_FLAGS-$(CONFIG_X86) += --rename-section .bss=.bss.efistub,load,alloc +STUBCOPY_RELOC-$(CONFIG_X86_32) := 'R_X86_32_(8|16|32)' +STUBCOPY_RELOC-$(CONFIG_X86_64) := 'R_X86_64_(8|16|32|32S|64)' $(obj)/%.stub.o: $(obj)/%.o FORCE $(call if_changed,stubcopy) @@ -107,16 +109,14 @@ $(obj)/%.stub.o: $(obj)/%.o FORCE # this time, use objcopy and leave all sections in place. # -cmd_stubrelocs_check-y = /bin/true - -cmd_stubrelocs_check-$(CONFIG_EFI_ARMSTUB) = \ +cmd_stubrelocs_check = \ $(STRIP) --strip-debug -o $@ $<; \ - if $(OBJDUMP) -r $@ | grep $(STUBCOPY_RELOC-y); then \ + if $(OBJDUMP) -r $@ | grep -E $(STUBCOPY_RELOC-y); then \ echo "$@: absolute symbol references not allowed in the EFI stub" >&2; \ /bin/false; \ fi quiet_cmd_stubcopy = STUBCPY $@ cmd_stubcopy = \ - $(cmd_stubrelocs_check-y); \ + $(cmd_stubrelocs_check); \ $(OBJCOPY) $(STUBCOPY_FLAGS-y) $< $@
Add relocation checking for x86 as well to catch non-PC-relative relocations that require runtime processing, since the EFI stub does not do any runtime relocation processing. This will catch, for example, data relocations created by static initializers of pointers. Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu> --- drivers/firmware/efi/libstub/Makefile | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-)