diff --git a/arch/arm/include/asm/assembler.h b/arch/arm/include/asm/assembler.h index 4abe57279c66f0..a9117704346739 100644 --- a/arch/arm/include/asm/assembler.h +++ b/arch/arm/include/asm/assembler.h @@ -445,6 +445,23 @@ THUMB( orr \reg , \reg , #PSR_T_BIT ) #endif .endm + .macro uaccess_disable, tmp, isb=1 + .endm + + .macro uaccess_enable, tmp, isb=1 + .endm + + .macro uaccess_save, tmp + .endm + + .macro uaccess_restore + .endm + + .macro uaccess_save_and_disable, tmp + uaccess_save \tmp + uaccess_disable \tmp + .endm + .irp c,,eq,ne,cs,cc,mi,pl,vs,vc,hi,ls,ge,lt,gt,le,hs,lo .macro ret\c, reg #if __LINUX_ARM_ARCH__ < 6 diff --git a/arch/arm/kernel/entry-armv.S b/arch/arm/kernel/entry-armv.S index d19adcf6c580c4..61f00a3f304765 100644 --- a/arch/arm/kernel/entry-armv.S +++ b/arch/arm/kernel/entry-armv.S @@ -149,10 +149,10 @@ ENDPROC(__und_invalid) #define SPFIX(code...) #endif - .macro svc_entry, stack_hole=0, trace=1 + .macro svc_entry, stack_hole=0, trace=1, uaccess=1 UNWIND(.fnstart ) UNWIND(.save {r0 - pc} ) - sub sp, sp, #(S_FRAME_SIZE + \stack_hole - 4) + sub sp, sp, #(S_FRAME_SIZE + 8 + \stack_hole - 4) #ifdef CONFIG_THUMB2_KERNEL SPFIX( str r0, [sp] ) @ temporarily saved SPFIX( mov r0, sp ) @@ -167,7 +167,7 @@ ENDPROC(__und_invalid) ldmia r0, {r3 - r5} add r7, sp, #S_SP - 4 @ here for interlock avoidance mov r6, #-1 @ "" "" "" "" - add r2, sp, #(S_FRAME_SIZE + \stack_hole - 4) + add r2, sp, #(S_FRAME_SIZE + 8 + \stack_hole - 4) SPFIX( addeq r2, r2, #4 ) str r3, [sp, #-4]! @ save the "real" r0 copied @ from the exception stack @@ -185,6 +185,11 @@ ENDPROC(__und_invalid) @ stmia r7, {r2 - r6} + uaccess_save r0 + .if \uaccess + uaccess_disable r0 + .endif + .if \trace #ifdef CONFIG_TRACE_IRQFLAGS bl trace_hardirqs_off @@ -194,7 +199,7 @@ ENDPROC(__und_invalid) .align 5 __dabt_svc: - svc_entry + svc_entry uaccess=0 mov r2, sp dabt_helper THUMB( ldr r5, [sp, #S_PSR] ) @ potentially updated CPSR @@ -368,7 +373,7 @@ ENDPROC(__fiq_abt) #error "sizeof(struct pt_regs) must be a multiple of 8" #endif - .macro usr_entry, trace=1 + .macro usr_entry, trace=1, uaccess=1 UNWIND(.fnstart ) UNWIND(.cantunwind ) @ don't unwind the user space sub sp, sp, #S_FRAME_SIZE @@ -400,6 +405,10 @@ ENDPROC(__fiq_abt) ARM( stmdb r0, {sp, lr}^ ) THUMB( store_user_sp_lr r0, r1, S_SP - S_PC ) + .if \uaccess + uaccess_disable ip + .endif + @ Enable the alignment trap while in kernel mode ATRAP( teq r8, r7) ATRAP( mcrne p15, 0, r8, c1, c0, 0) @@ -435,7 +444,7 @@ ENDPROC(__fiq_abt) .align 5 __dabt_usr: - usr_entry + usr_entry uaccess=0 kuser_cmpxchg_check mov r2, sp dabt_helper @@ -458,7 +467,7 @@ ENDPROC(__irq_usr) .align 5 __und_usr: - usr_entry + usr_entry uaccess=0 mov r2, r4 mov r3, r5 @@ -484,6 +493,8 @@ __und_usr: 1: ldrt r0, [r4] ARM_BE8(rev r0, r0) @ little endian instruction + uaccess_disable ip + @ r0 = 32-bit ARM instruction which caused the exception @ r2 = PC value for the following instruction (:= regs->ARM_pc) @ r4 = PC value for the faulting instruction @@ -518,9 +529,10 @@ __und_usr_thumb: 2: ldrht r5, [r4] ARM_BE8(rev16 r5, r5) @ little endian instruction cmp r5, #0xe800 @ 32bit instruction if xx != 0 - blo __und_usr_fault_16 @ 16bit undefined instruction + blo __und_usr_fault_16_pan @ 16bit undefined instruction 3: ldrht r0, [r2] ARM_BE8(rev16 r0, r0) @ little endian instruction + uaccess_disable ip add r2, r2, #2 @ r2 is PC + 2, make it PC + 4 str r2, [sp, #S_PC] @ it's a 2x16bit instr, update orr r0, r0, r5, lsl #16 @@ -715,6 +727,8 @@ ENDPROC(no_fp) __und_usr_fault_32: mov r1, #4 b 1f +__und_usr_fault_16_pan: + uaccess_disable ip __und_usr_fault_16: mov r1, #2 1: mov r0, sp diff --git a/arch/arm/kernel/entry-common.S b/arch/arm/kernel/entry-common.S index 92828a1dec80c1..1891549807036f 100644 --- a/arch/arm/kernel/entry-common.S +++ b/arch/arm/kernel/entry-common.S @@ -173,6 +173,8 @@ ENTRY(vector_swi) USER( ldr scno, [lr, #-4] ) @ get SWI instruction #endif + uaccess_disable tbl + adr tbl, sys_call_table @ load syscall table pointer #if defined(CONFIG_OABI_COMPAT) diff --git a/arch/arm/kernel/entry-header.S b/arch/arm/kernel/entry-header.S index d47b5161b029e1..0d22ad206d5230 100644 --- a/arch/arm/kernel/entry-header.S +++ b/arch/arm/kernel/entry-header.S @@ -215,6 +215,7 @@ blne trace_hardirqs_off #endif .endif + uaccess_restore #ifndef CONFIG_THUMB2_KERNEL @ ARM mode SVC restore @@ -258,6 +259,7 @@ @ on the stack remains correct). @ .macro svc_exit_via_fiq + uaccess_restore #ifndef CONFIG_THUMB2_KERNEL @ ARM mode restore mov r0, sp @@ -287,6 +289,7 @@ .macro restore_user_regs, fast = 0, offset = 0 + uaccess_enable r1, isb=0 #ifndef CONFIG_THUMB2_KERNEL @ ARM mode restore mov r2, sp diff --git a/arch/arm/mm/abort-ev4.S b/arch/arm/mm/abort-ev4.S index 54473cd4aba951..b3b31e30cadd20 100644 --- a/arch/arm/mm/abort-ev4.S +++ b/arch/arm/mm/abort-ev4.S @@ -19,6 +19,7 @@ ENTRY(v4_early_abort) mrc p15, 0, r1, c5, c0, 0 @ get FSR mrc p15, 0, r0, c6, c0, 0 @ get FAR ldr r3, [r4] @ read aborted ARM instruction + uaccess_disable ip @ disable userspace access bic r1, r1, #1 << 11 | 1 << 10 @ clear bits 11 and 10 of FSR tst r3, #1 << 20 @ L = 1 -> write? orreq r1, r1, #1 << 11 @ yes. diff --git a/arch/arm/mm/abort-ev5t.S b/arch/arm/mm/abort-ev5t.S index c913031b79ccba..a6a381a6caa5a3 100644 --- a/arch/arm/mm/abort-ev5t.S +++ b/arch/arm/mm/abort-ev5t.S @@ -21,6 +21,7 @@ ENTRY(v5t_early_abort) mrc p15, 0, r0, c6, c0, 0 @ get FAR do_thumb_abort fsr=r1, pc=r4, psr=r5, tmp=r3 ldreq r3, [r4] @ read aborted ARM instruction + uaccess_disable ip @ disable user access bic r1, r1, #1 << 11 @ clear bits 11 of FSR teq_ldrd tmp=ip, insn=r3 @ insn was LDRD? beq do_DataAbort @ yes diff --git a/arch/arm/mm/abort-ev5tj.S b/arch/arm/mm/abort-ev5tj.S index 1b80d71adb0ff1..00ab011bef5848 100644 --- a/arch/arm/mm/abort-ev5tj.S +++ b/arch/arm/mm/abort-ev5tj.S @@ -24,6 +24,7 @@ ENTRY(v5tj_early_abort) bne do_DataAbort do_thumb_abort fsr=r1, pc=r4, psr=r5, tmp=r3 ldreq r3, [r4] @ read aborted ARM instruction + uaccess_disable ip @ disable userspace access teq_ldrd tmp=ip, insn=r3 @ insn was LDRD? beq do_DataAbort @ yes tst r3, #1 << 20 @ L = 0 -> write diff --git a/arch/arm/mm/abort-ev6.S b/arch/arm/mm/abort-ev6.S index 113704f30e9f88..8801a15aa10595 100644 --- a/arch/arm/mm/abort-ev6.S +++ b/arch/arm/mm/abort-ev6.S @@ -26,17 +26,18 @@ ENTRY(v6_early_abort) ldr ip, =0x4107b36 mrc p15, 0, r3, c0, c0, 0 @ get processor id teq ip, r3, lsr #4 @ r0 ARM1136? - bne do_DataAbort + bne 1f tst r5, #PSR_J_BIT @ Java? tsteq r5, #PSR_T_BIT @ Thumb? - bne do_DataAbort + bne 1f bic r1, r1, #1 << 11 @ clear bit 11 of FSR ldr r3, [r4] @ read aborted ARM instruction ARM_BE8(rev r3, r3) teq_ldrd tmp=ip, insn=r3 @ insn was LDRD? - beq do_DataAbort @ yes + beq 1f @ yes tst r3, #1 << 20 @ L = 0 -> write orreq r1, r1, #1 << 11 @ yes. #endif +1: uaccess_disable ip @ disable userspace access b do_DataAbort diff --git a/arch/arm/mm/abort-ev7.S b/arch/arm/mm/abort-ev7.S index 4812ad05421457..e8d0e08c227fc5 100644 --- a/arch/arm/mm/abort-ev7.S +++ b/arch/arm/mm/abort-ev7.S @@ -15,6 +15,7 @@ ENTRY(v7_early_abort) mrc p15, 0, r1, c5, c0, 0 @ get FSR mrc p15, 0, r0, c6, c0, 0 @ get FAR + uaccess_disable ip @ disable userspace access /* * V6 code adjusts the returned DFSR. diff --git a/arch/arm/mm/abort-lv4t.S b/arch/arm/mm/abort-lv4t.S index f3982580c27305..6d8e8e3365d173 100644 --- a/arch/arm/mm/abort-lv4t.S +++ b/arch/arm/mm/abort-lv4t.S @@ -26,6 +26,7 @@ ENTRY(v4t_late_abort) #endif bne .data_thumb_abort ldr r8, [r4] @ read arm instruction + uaccess_disable ip @ disable userspace access tst r8, #1 << 20 @ L = 1 -> write? orreq r1, r1, #1 << 11 @ yes. and r7, r8, #15 << 24 @@ -155,6 +156,7 @@ ENTRY(v4t_late_abort) .data_thumb_abort: ldrh r8, [r4] @ read instruction + uaccess_disable ip @ disable userspace access tst r8, #1 << 11 @ L = 1 -> write? orreq r1, r1, #1 << 8 @ yes and r7, r8, #15 << 12 diff --git a/arch/arm/mm/abort-macro.S b/arch/arm/mm/abort-macro.S index 50d6c0a900b14d..4509bee4e081ce 100644 --- a/arch/arm/mm/abort-macro.S +++ b/arch/arm/mm/abort-macro.S @@ -13,6 +13,7 @@ tst \psr, #PSR_T_BIT beq not_thumb ldrh \tmp, [\pc] @ Read aborted Thumb instruction + uaccess_disable ip @ disable userspace access and \tmp, \tmp, # 0xfe00 @ Mask opcode field cmp \tmp, # 0x5600 @ Is it ldrsb? orreq \tmp, \tmp, #1 << 11 @ Set L-bit if yes