From a3c195144e162097c42e4284323ed6d386de105d Mon Sep 17 00:00:00 2001 From: Bobby Bingham Date: Thu, 3 Apr 2014 14:46:41 -0700 Subject: sh: don't pass saved userspace state to exception handlers The compiler is permitted to generate code which overwrites the parameters to a function. If those parameters include the only saved copy we have of userspace's registers, we're in trouble. Signed-off-by: Bobby Bingham Cc: Paul Mundt Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- arch/sh/include/asm/traps_32.h | 16 ++++------------ arch/sh/kernel/traps_32.c | 23 +++++++---------------- 2 files changed, 11 insertions(+), 28 deletions(-) diff --git a/arch/sh/include/asm/traps_32.h b/arch/sh/include/asm/traps_32.h index cfd55ff9dff..17e129fe459 100644 --- a/arch/sh/include/asm/traps_32.h +++ b/arch/sh/include/asm/traps_32.h @@ -42,18 +42,10 @@ static inline void trigger_address_error(void) asmlinkage void do_address_error(struct pt_regs *regs, unsigned long writeaccess, unsigned long address); -asmlinkage void do_divide_error(unsigned long r4, unsigned long r5, - unsigned long r6, unsigned long r7, - struct pt_regs __regs); -asmlinkage void do_reserved_inst(unsigned long r4, unsigned long r5, - unsigned long r6, unsigned long r7, - struct pt_regs __regs); -asmlinkage void do_illegal_slot_inst(unsigned long r4, unsigned long r5, - unsigned long r6, unsigned long r7, - struct pt_regs __regs); -asmlinkage void do_exception_error(unsigned long r4, unsigned long r5, - unsigned long r6, unsigned long r7, - struct pt_regs __regs); +asmlinkage void do_divide_error(unsigned long r4); +asmlinkage void do_reserved_inst(void); +asmlinkage void do_illegal_slot_inst(void); +asmlinkage void do_exception_error(void); #define BUILD_TRAP_HANDLER(name) \ asmlinkage void name##_trap_handler(unsigned long r4, unsigned long r5, \ diff --git a/arch/sh/kernel/traps_32.c b/arch/sh/kernel/traps_32.c index 68e99f09171..ff639342a8b 100644 --- a/arch/sh/kernel/traps_32.c +++ b/arch/sh/kernel/traps_32.c @@ -594,9 +594,7 @@ int is_dsp_inst(struct pt_regs *regs) #endif /* CONFIG_SH_DSP */ #ifdef CONFIG_CPU_SH2A -asmlinkage void do_divide_error(unsigned long r4, unsigned long r5, - unsigned long r6, unsigned long r7, - struct pt_regs __regs) +asmlinkage void do_divide_error(unsigned long r4) { siginfo_t info; @@ -613,11 +611,9 @@ asmlinkage void do_divide_error(unsigned long r4, unsigned long r5, } #endif -asmlinkage void do_reserved_inst(unsigned long r4, unsigned long r5, - unsigned long r6, unsigned long r7, - struct pt_regs __regs) +asmlinkage void do_reserved_inst(void) { - struct pt_regs *regs = RELOC_HIDE(&__regs, 0); + struct pt_regs *regs = current_pt_regs(); unsigned long error_code; struct task_struct *tsk = current; @@ -701,11 +697,9 @@ static int emulate_branch(unsigned short inst, struct pt_regs *regs) } #endif -asmlinkage void do_illegal_slot_inst(unsigned long r4, unsigned long r5, - unsigned long r6, unsigned long r7, - struct pt_regs __regs) +asmlinkage void do_illegal_slot_inst(void) { - struct pt_regs *regs = RELOC_HIDE(&__regs, 0); + struct pt_regs *regs = current_pt_regs(); unsigned long inst; struct task_struct *tsk = current; @@ -730,15 +724,12 @@ asmlinkage void do_illegal_slot_inst(unsigned long r4, unsigned long r5, die_if_no_fixup("illegal slot instruction", regs, inst); } -asmlinkage void do_exception_error(unsigned long r4, unsigned long r5, - unsigned long r6, unsigned long r7, - struct pt_regs __regs) +asmlinkage void do_exception_error(void) { - struct pt_regs *regs = RELOC_HIDE(&__regs, 0); long ex; ex = lookup_exception_vector(); - die_if_kernel("exception", regs, ex); + die_if_kernel("exception", current_pt_regs(), ex); } void per_cpu_trap_init(void) -- cgit v1.2.3-70-g09d2