diff options
author | Russell King <rmk+kernel@armlinux.org.uk> | 2020-05-07 20:53:53 +0100 |
---|---|---|
committer | Russell King <rmk+kernel@armlinux.org.uk> | 2020-05-07 20:53:53 +0100 |
commit | 513149cba8f2b2cadf1e0ecc13d008cb78a455c8 (patch) | |
tree | 47c2bc3a1a0a1ba3eac7286a74894da76a4b1b5f /arch/arm/include | |
parent | 1f13aa4d5194cbbc7934012069c05a60fc697df9 (diff) | |
parent | 71f8af1110101facfad68989ff91f88f8e2c3e22 (diff) |
Merge branch 'uaccess' into fixes
Diffstat (limited to 'arch/arm/include')
-rw-r--r-- | arch/arm/include/asm/assembler.h | 75 | ||||
-rw-r--r-- | arch/arm/include/asm/uaccess-asm.h | 117 |
2 files changed, 118 insertions, 74 deletions
diff --git a/arch/arm/include/asm/assembler.h b/arch/arm/include/asm/assembler.h index 99929122dad7..3546d294d55f 100644 --- a/arch/arm/include/asm/assembler.h +++ b/arch/arm/include/asm/assembler.h @@ -18,11 +18,11 @@ #endif #include <asm/ptrace.h> -#include <asm/domain.h> #include <asm/opcodes-virt.h> #include <asm/asm-offsets.h> #include <asm/page.h> #include <asm/thread_info.h> +#include <asm/uaccess-asm.h> #define IOMEM(x) (x) @@ -446,79 +446,6 @@ THUMB( orr \reg , \reg , #PSR_T_BIT ) .size \name , . - \name .endm - .macro csdb -#ifdef CONFIG_THUMB2_KERNEL - .inst.w 0xf3af8014 -#else - .inst 0xe320f014 -#endif - .endm - - .macro check_uaccess, addr:req, size:req, limit:req, tmp:req, bad:req -#ifndef CONFIG_CPU_USE_DOMAINS - adds \tmp, \addr, #\size - 1 - sbcscc \tmp, \tmp, \limit - bcs \bad -#ifdef CONFIG_CPU_SPECTRE - movcs \addr, #0 - csdb -#endif -#endif - .endm - - .macro uaccess_mask_range_ptr, addr:req, size:req, limit:req, tmp:req -#ifdef CONFIG_CPU_SPECTRE - sub \tmp, \limit, #1 - subs \tmp, \tmp, \addr @ tmp = limit - 1 - addr - addhs \tmp, \tmp, #1 @ if (tmp >= 0) { - subshs \tmp, \tmp, \size @ tmp = limit - (addr + size) } - movlo \addr, #0 @ if (tmp < 0) addr = NULL - csdb -#endif - .endm - - .macro uaccess_disable, tmp, isb=1 -#ifdef CONFIG_CPU_SW_DOMAIN_PAN - /* - * Whenever we re-enter userspace, the domains should always be - * set appropriately. - */ - mov \tmp, #DACR_UACCESS_DISABLE - mcr p15, 0, \tmp, c3, c0, 0 @ Set domain register - .if \isb - instr_sync - .endif -#endif - .endm - - .macro uaccess_enable, tmp, isb=1 -#ifdef CONFIG_CPU_SW_DOMAIN_PAN - /* - * Whenever we re-enter userspace, the domains should always be - * set appropriately. - */ - mov \tmp, #DACR_UACCESS_ENABLE - mcr p15, 0, \tmp, c3, c0, 0 - .if \isb - instr_sync - .endif -#endif - .endm - - .macro uaccess_save, tmp -#ifdef CONFIG_CPU_SW_DOMAIN_PAN - mrc p15, 0, \tmp, c3, c0, 0 - str \tmp, [sp, #SVC_DACR] -#endif - .endm - - .macro uaccess_restore -#ifdef CONFIG_CPU_SW_DOMAIN_PAN - ldr r0, [sp, #SVC_DACR] - mcr p15, 0, r0, c3, c0, 0 -#endif - .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/include/asm/uaccess-asm.h b/arch/arm/include/asm/uaccess-asm.h new file mode 100644 index 000000000000..907571fd05c6 --- /dev/null +++ b/arch/arm/include/asm/uaccess-asm.h @@ -0,0 +1,117 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ + +#ifndef __ASM_UACCESS_ASM_H__ +#define __ASM_UACCESS_ASM_H__ + +#include <asm/asm-offsets.h> +#include <asm/domain.h> +#include <asm/memory.h> +#include <asm/thread_info.h> + + .macro csdb +#ifdef CONFIG_THUMB2_KERNEL + .inst.w 0xf3af8014 +#else + .inst 0xe320f014 +#endif + .endm + + .macro check_uaccess, addr:req, size:req, limit:req, tmp:req, bad:req +#ifndef CONFIG_CPU_USE_DOMAINS + adds \tmp, \addr, #\size - 1 + sbcscc \tmp, \tmp, \limit + bcs \bad +#ifdef CONFIG_CPU_SPECTRE + movcs \addr, #0 + csdb +#endif +#endif + .endm + + .macro uaccess_mask_range_ptr, addr:req, size:req, limit:req, tmp:req +#ifdef CONFIG_CPU_SPECTRE + sub \tmp, \limit, #1 + subs \tmp, \tmp, \addr @ tmp = limit - 1 - addr + addhs \tmp, \tmp, #1 @ if (tmp >= 0) { + subshs \tmp, \tmp, \size @ tmp = limit - (addr + size) } + movlo \addr, #0 @ if (tmp < 0) addr = NULL + csdb +#endif + .endm + + .macro uaccess_disable, tmp, isb=1 +#ifdef CONFIG_CPU_SW_DOMAIN_PAN + /* + * Whenever we re-enter userspace, the domains should always be + * set appropriately. + */ + mov \tmp, #DACR_UACCESS_DISABLE + mcr p15, 0, \tmp, c3, c0, 0 @ Set domain register + .if \isb + instr_sync + .endif +#endif + .endm + + .macro uaccess_enable, tmp, isb=1 +#ifdef CONFIG_CPU_SW_DOMAIN_PAN + /* + * Whenever we re-enter userspace, the domains should always be + * set appropriately. + */ + mov \tmp, #DACR_UACCESS_ENABLE + mcr p15, 0, \tmp, c3, c0, 0 + .if \isb + instr_sync + .endif +#endif + .endm + +#if defined(CONFIG_CPU_SW_DOMAIN_PAN) || defined(CONFIG_CPU_USE_DOMAINS) +#define DACR(x...) x +#else +#define DACR(x...) +#endif + + /* + * Save the address limit on entry to a privileged exception. + * + * If we are using the DACR for kernel access by the user accessors + * (CONFIG_CPU_USE_DOMAINS=y), always reset the DACR kernel domain + * back to client mode, whether or not \disable is set. + * + * If we are using SW PAN, set the DACR user domain to no access + * if \disable is set. + */ + .macro uaccess_entry, tsk, tmp0, tmp1, tmp2, disable + ldr \tmp1, [\tsk, #TI_ADDR_LIMIT] + mov \tmp2, #TASK_SIZE + str \tmp2, [\tsk, #TI_ADDR_LIMIT] + DACR( mrc p15, 0, \tmp0, c3, c0, 0) + DACR( str \tmp0, [sp, #SVC_DACR]) + str \tmp1, [sp, #SVC_ADDR_LIMIT] + .if \disable && IS_ENABLED(CONFIG_CPU_SW_DOMAIN_PAN) + /* kernel=client, user=no access */ + mov \tmp2, #DACR_UACCESS_DISABLE + mcr p15, 0, \tmp2, c3, c0, 0 + instr_sync + .elseif IS_ENABLED(CONFIG_CPU_USE_DOMAINS) + /* kernel=client */ + bic \tmp2, \tmp0, #domain_mask(DOMAIN_KERNEL) + orr \tmp2, \tmp2, #domain_val(DOMAIN_KERNEL, DOMAIN_CLIENT) + mcr p15, 0, \tmp2, c3, c0, 0 + instr_sync + .endif + .endm + + /* Restore the user access state previously saved by uaccess_entry */ + .macro uaccess_exit, tsk, tmp0, tmp1 + ldr \tmp1, [sp, #SVC_ADDR_LIMIT] + DACR( ldr \tmp0, [sp, #SVC_DACR]) + str \tmp1, [\tsk, #TI_ADDR_LIMIT] + DACR( mcr p15, 0, \tmp0, c3, c0, 0) + .endm + +#undef DACR + +#endif /* __ASM_UACCESS_ASM_H__ */ |