From 752a6422fec3c0f5f9d4ac43d92f5dd13e22fde4 Mon Sep 17 00:00:00 2001 From: Ulrich Weigand Date: Fri, 14 Feb 2014 19:21:03 +0100 Subject: [PATCH] powerpc: Fix unsafe accesses to parameter area in ELFv2 Some of the assembler files in lib/ make use of the fact that in the ELFv1 ABI, the caller guarantees to provide stack space to save the parameter registers r3 ... r10. This guarantee is no longer present in ELFv2 for functions that have no variable argument list and no more than 8 arguments. Change the affected routines to temporarily store registers in the red zone and/or the top of their own stack frame (in the space provided to save r31 .. r29, which is actually not used in these routines). In opal_query_takeover, simply always allocate a stack frame; the routine is not performance critical. Signed-off-by: Ulrich Weigand Signed-off-by: Anton Blanchard --- arch/powerpc/lib/copypage_power7.S | 8 +++---- arch/powerpc/lib/copyuser_power7.S | 24 +++++++++---------- arch/powerpc/lib/memcpy_64.S | 8 +++---- arch/powerpc/lib/memcpy_power7.S | 20 ++++++++-------- .../powerpc/platforms/powernv/opal-takeover.S | 2 ++ 5 files changed, 32 insertions(+), 30 deletions(-) diff --git a/arch/powerpc/lib/copypage_power7.S b/arch/powerpc/lib/copypage_power7.S index affc6d308e13..d7dafb3777ac 100644 --- a/arch/powerpc/lib/copypage_power7.S +++ b/arch/powerpc/lib/copypage_power7.S @@ -56,15 +56,15 @@ _GLOBAL(copypage_power7) #ifdef CONFIG_ALTIVEC mflr r0 - std r3,STK_PARAM(R3)(r1) - std r4,STK_PARAM(R4)(r1) + std r3,-STACKFRAMESIZE+STK_REG(R31)(r1) + std r4,-STACKFRAMESIZE+STK_REG(R30)(r1) std r0,16(r1) stdu r1,-STACKFRAMESIZE(r1) bl enter_vmx_copy cmpwi r3,0 ld r0,STACKFRAMESIZE+16(r1) - ld r3,STACKFRAMESIZE+STK_PARAM(R3)(r1) - ld r4,STACKFRAMESIZE+STK_PARAM(R4)(r1) + ld r3,STK_REG(R31)(r1) + ld r4,STK_REG(R30)(r1) mtlr r0 li r0,(PAGE_SIZE/128) diff --git a/arch/powerpc/lib/copyuser_power7.S b/arch/powerpc/lib/copyuser_power7.S index db0fcbcc1d60..c46c876ac96a 100644 --- a/arch/powerpc/lib/copyuser_power7.S +++ b/arch/powerpc/lib/copyuser_power7.S @@ -85,9 +85,9 @@ .Lexit: addi r1,r1,STACKFRAMESIZE .Ldo_err1: - ld r3,STK_PARAM(R3)(r1) - ld r4,STK_PARAM(R4)(r1) - ld r5,STK_PARAM(R5)(r1) + ld r3,-STACKFRAMESIZE+STK_REG(R31)(r1) + ld r4,-STACKFRAMESIZE+STK_REG(R30)(r1) + ld r5,-STACKFRAMESIZE+STK_REG(R29)(r1) b __copy_tofrom_user_base @@ -96,18 +96,18 @@ _GLOBAL(__copy_tofrom_user_power7) cmpldi r5,16 cmpldi cr1,r5,4096 - std r3,STK_PARAM(R3)(r1) - std r4,STK_PARAM(R4)(r1) - std r5,STK_PARAM(R5)(r1) + std r3,-STACKFRAMESIZE+STK_REG(R31)(r1) + std r4,-STACKFRAMESIZE+STK_REG(R30)(r1) + std r5,-STACKFRAMESIZE+STK_REG(R29)(r1) blt .Lshort_copy bgt cr1,.Lvmx_copy #else cmpldi r5,16 - std r3,STK_PARAM(R3)(r1) - std r4,STK_PARAM(R4)(r1) - std r5,STK_PARAM(R5)(r1) + std r3,-STACKFRAMESIZE+STK_REG(R31)(r1) + std r4,-STACKFRAMESIZE+STK_REG(R30)(r1) + std r5,-STACKFRAMESIZE+STK_REG(R29)(r1) blt .Lshort_copy #endif @@ -298,9 +298,9 @@ err1; stb r0,0(r3) bl enter_vmx_usercopy cmpwi cr1,r3,0 ld r0,STACKFRAMESIZE+16(r1) - ld r3,STACKFRAMESIZE+STK_PARAM(R3)(r1) - ld r4,STACKFRAMESIZE+STK_PARAM(R4)(r1) - ld r5,STACKFRAMESIZE+STK_PARAM(R5)(r1) + ld r3,STK_REG(R31)(r1) + ld r4,STK_REG(R30)(r1) + ld r5,STK_REG(R29)(r1) mtlr r0 /* diff --git a/arch/powerpc/lib/memcpy_64.S b/arch/powerpc/lib/memcpy_64.S index 01da956a52fb..9d3960c16fde 100644 --- a/arch/powerpc/lib/memcpy_64.S +++ b/arch/powerpc/lib/memcpy_64.S @@ -12,7 +12,7 @@ .align 7 _GLOBAL(memcpy) BEGIN_FTR_SECTION - std r3,STK_PARAM(R3)(r1) /* save destination pointer for return value */ + std r3,-STACKFRAMESIZE+STK_REG(R31)(r1) /* save destination pointer for return value */ FTR_SECTION_ELSE #ifndef SELFTEST b memcpy_power7 @@ -73,7 +73,7 @@ END_FTR_SECTION_IFCLR(CPU_FTR_UNALIGNED_LD_STD) 2: bf cr7*4+3,3f lbz r9,8(r4) stb r9,0(r3) -3: ld r3,STK_PARAM(R3)(r1) /* return dest pointer */ +3: ld r3,-STACKFRAMESIZE+STK_REG(R31)(r1) /* return dest pointer */ blr .Lsrc_unaligned: @@ -156,7 +156,7 @@ END_FTR_SECTION_IFCLR(CPU_FTR_UNALIGNED_LD_STD) 2: bf cr7*4+3,3f rotldi r9,r9,8 stb r9,0(r3) -3: ld r3,STK_PARAM(R3)(r1) /* return dest pointer */ +3: ld r3,-STACKFRAMESIZE+STK_REG(R31)(r1) /* return dest pointer */ blr .Ldst_unaligned: @@ -201,5 +201,5 @@ END_FTR_SECTION_IFCLR(CPU_FTR_UNALIGNED_LD_STD) 3: bf cr7*4+3,4f lbz r0,0(r4) stb r0,0(r3) -4: ld r3,STK_PARAM(R3)(r1) /* return dest pointer */ +4: ld r3,-STACKFRAMESIZE+STK_REG(R31)(r1) /* return dest pointer */ blr diff --git a/arch/powerpc/lib/memcpy_power7.S b/arch/powerpc/lib/memcpy_power7.S index 87d8eeccd4b7..2ff5c142f87b 100644 --- a/arch/powerpc/lib/memcpy_power7.S +++ b/arch/powerpc/lib/memcpy_power7.S @@ -33,14 +33,14 @@ _GLOBAL(memcpy_power7) cmpldi r5,16 cmpldi cr1,r5,4096 - std r3,STK_PARAM(R1)(r1) + std r3,-STACKFRAMESIZE+STK_REG(R31)(r1) blt .Lshort_copy bgt cr1,.Lvmx_copy #else cmpldi r5,16 - std r3,STK_PARAM(R1)(r1) + std r3,-STACKFRAMESIZE+STK_REG(R31)(r1) blt .Lshort_copy #endif @@ -216,7 +216,7 @@ _GLOBAL(memcpy_power7) lbz r0,0(r4) stb r0,0(r3) -15: ld r3,STK_PARAM(R3)(r1) +15: ld r3,-STACKFRAMESIZE+STK_REG(R31)(r1) blr .Lunwind_stack_nonvmx_copy: @@ -226,16 +226,16 @@ _GLOBAL(memcpy_power7) #ifdef CONFIG_ALTIVEC .Lvmx_copy: mflr r0 - std r4,STK_PARAM(R4)(r1) - std r5,STK_PARAM(R5)(r1) + std r4,-STACKFRAMESIZE+STK_REG(R30)(r1) + std r5,-STACKFRAMESIZE+STK_REG(R29)(r1) std r0,16(r1) stdu r1,-STACKFRAMESIZE(r1) bl enter_vmx_copy cmpwi cr1,r3,0 ld r0,STACKFRAMESIZE+16(r1) - ld r3,STACKFRAMESIZE+STK_PARAM(R3)(r1) - ld r4,STACKFRAMESIZE+STK_PARAM(R4)(r1) - ld r5,STACKFRAMESIZE+STK_PARAM(R5)(r1) + ld r3,STK_REG(R31)(r1) + ld r4,STK_REG(R30)(r1) + ld r5,STK_REG(R29)(r1) mtlr r0 /* @@ -447,7 +447,7 @@ _GLOBAL(memcpy_power7) stb r0,0(r3) 15: addi r1,r1,STACKFRAMESIZE - ld r3,STK_PARAM(R3)(r1) + ld r3,-STACKFRAMESIZE+STK_REG(R31)(r1) b exit_vmx_copy /* tail call optimise */ .Lvmx_unaligned_copy: @@ -651,6 +651,6 @@ _GLOBAL(memcpy_power7) stb r0,0(r3) 15: addi r1,r1,STACKFRAMESIZE - ld r3,STK_PARAM(R3)(r1) + ld r3,-STACKFRAMESIZE+STK_REG(R31)(r1) b exit_vmx_copy /* tail call optimise */ #endif /* CONFiG_ALTIVEC */ diff --git a/arch/powerpc/platforms/powernv/opal-takeover.S b/arch/powerpc/platforms/powernv/opal-takeover.S index 3cd262897c27..11a3169ee583 100644 --- a/arch/powerpc/platforms/powernv/opal-takeover.S +++ b/arch/powerpc/platforms/powernv/opal-takeover.S @@ -21,11 +21,13 @@ _GLOBAL(opal_query_takeover) mfcr r0 stw r0,8(r1) + stdu r1,-STACKFRAMESIZE(r1) std r3,STK_PARAM(R3)(r1) std r4,STK_PARAM(R4)(r1) li r3,H_HAL_TAKEOVER li r4,H_HAL_TAKEOVER_QUERY_MAGIC HVSC + addi r1,r1,STACKFRAMESIZE ld r10,STK_PARAM(R3)(r1) std r4,0(r10) ld r10,STK_PARAM(R4)(r1) -- 2.39.5