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| author | Sami Tolvanen <samitolvanen@google.com> | 2023-09-28 00:48:02 +0200 |
|---|---|---|
| committer | Palmer Dabbelt <palmer@rivosinc.com> | 2023-10-27 23:43:08 +0200 |
| commit | d1584d791a297aa8ed93503382a682a6ecfc4218 (patch) | |
| tree | 371b56adbd1d77f436e143555ab9fb47b4ad50c0 /arch/riscv/Makefile | |
| parent | riscv: Move global pointer loading to a macro (diff) | |
| download | linux-d1584d791a297aa8ed93503382a682a6ecfc4218.tar.xz linux-d1584d791a297aa8ed93503382a682a6ecfc4218.zip | |
riscv: Implement Shadow Call Stack
Implement CONFIG_SHADOW_CALL_STACK for RISC-V. When enabled, the
compiler injects instructions to all non-leaf C functions to
store the return address to the shadow stack and unconditionally
load it again before returning, which makes it harder to corrupt
the return address through a stack overflow, for example.
The active shadow call stack pointer is stored in the gp
register, which makes SCS incompatible with gp relaxation. Use
--no-relax-gp to ensure gp relaxation is disabled and disable
global pointer loading. Add SCS pointers to struct thread_info,
implement SCS initialization, and task switching
Signed-off-by: Sami Tolvanen <samitolvanen@google.com>
Tested-by: Nathan Chancellor <nathan@kernel.org>
Link: https://lore.kernel.org/r/20230927224757.1154247-12-samitolvanen@google.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
Diffstat (limited to 'arch/riscv/Makefile')
| -rw-r--r-- | arch/riscv/Makefile | 4 |
1 files changed, 4 insertions, 0 deletions
diff --git a/arch/riscv/Makefile b/arch/riscv/Makefile index 1329e060c548..304b94446507 100644 --- a/arch/riscv/Makefile +++ b/arch/riscv/Makefile @@ -55,6 +55,10 @@ endif endif endif +ifeq ($(CONFIG_SHADOW_CALL_STACK),y) + KBUILD_LDFLAGS += --no-relax-gp +endif + # ISA string setting riscv-march-$(CONFIG_ARCH_RV32I) := rv32ima riscv-march-$(CONFIG_ARCH_RV64I) := rv64ima |