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Signed-off-by: Yunhui Cui --- arch/riscv/include/asm/exec.h | 8 ++++++++ arch/riscv/kernel/process.c | 9 +++++++++ 2 files changed, 17 insertions(+) create mode 100644 arch/riscv/include/asm/exec.h diff --git a/arch/riscv/include/asm/exec.h b/arch/riscv/include/asm/exec.h new file mode 100644 index 000000000000..07d9942682e0 --- /dev/null +++ b/arch/riscv/include/asm/exec.h @@ -0,0 +1,8 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ + +#ifndef __ASM_EXEC_H +#define __ASM_EXEC_H + +extern unsigned long arch_align_stack(unsigned long sp); + +#endif /* __ASM_EXEC_H */ diff --git a/arch/riscv/kernel/process.c b/arch/riscv/kernel/process.c index e4bc61c4e58a..e3142d8a6e28 100644 --- a/arch/riscv/kernel/process.c +++ b/arch/riscv/kernel/process.c @@ -15,6 +15,7 @@ #include #include #include +#include =20 #include #include @@ -26,6 +27,7 @@ #include #include #include +#include =20 #if defined(CONFIG_STACKPROTECTOR) && !defined(CONFIG_STACKPROTECTOR_PER_T= ASK) #include @@ -99,6 +101,13 @@ void show_regs(struct pt_regs *regs) dump_backtrace(regs, NULL, KERN_DEFAULT); } =20 +unsigned long arch_align_stack(unsigned long sp) +{ + if (!(current->personality & ADDR_NO_RANDOMIZE) && randomize_va_space) + sp -=3D get_random_u32_below(PAGE_SIZE); + return sp & ~0xf; +} + #ifdef CONFIG_COMPAT static bool compat_mode_supported __read_mostly; =20 --=20 2.20.1