riscv/efistub: Ensure GP-relative addressing is not used

commit afb2a4fb84555ef9e61061f6ea63ed7087b295d5 upstream.

The cflags for the RISC-V efistub were missing -mno-relax, thus were
under the risk that the compiler could use GP-relative addressing. That
happened for _edata with binutils-2.41 and kernel 6.1, causing the
relocation to fail due to an invalid kernel_size in handle_kernel_image.
It was not yet observed with newer versions, but that may just be luck.

Cc: <stable@vger.kernel.org>
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/firmware/efi/libstub/Makefile b/drivers/firmware/efi/libstub/Makefile
index ef4c12f0877ba428f55db3510771da69b0c7cad9..a0f1569b790da543ec6510241b179159d1d8afc2 100644 (file)
--- a/drivers/firmware/efi/libstub/Makefile
+++ b/drivers/firmware/efi/libstub/Makefile
@@ -28,7 +28,7 @@ cflags-$(CONFIG_ARM)          += -DEFI_HAVE_STRLEN -DEFI_HAVE_STRNLEN \
                                   -DEFI_HAVE_MEMCHR -DEFI_HAVE_STRRCHR \
                                   -DEFI_HAVE_STRCMP -fno-builtin -fpic \
                                   $(call cc-option,-mno-single-pic-base)
-cflags-$(CONFIG_RISCV)         += -fpic
+cflags-$(CONFIG_RISCV)         += -fpic -mno-relax
 cflags-$(CONFIG_LOONGARCH)     += -fpie
 
 cflags-$(CONFIG_EFI_PARAMS_FROM_FDT)   += -I$(srctree)/scripts/dtc/libfdt