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| author | Catalin Marinas <catalin.marinas@arm.com> | 2016-07-01 14:58:21 +0100 |
|---|---|---|
| committer | Catalin Marinas <catalin.marinas@arm.com> | 2016-11-21 17:33:47 +0000 |
| commit | bd38967d406fb4f9fca67d612db71b5d74cfb0f5 (patch) | |
| tree | fbcc9bd2e2f70c40387fe166de6f4e874c0d0bdb /arch/arm64/lib | |
| parent | a8ada146f5179793bbaff3c936d73147ccd47ba2 (diff) | |
| download | linux-bd38967d406fb4f9fca67d612db71b5d74cfb0f5.tar.gz linux-bd38967d406fb4f9fca67d612db71b5d74cfb0f5.tar.bz2 linux-bd38967d406fb4f9fca67d612db71b5d74cfb0f5.zip | |
arm64: Factor out PAN enabling/disabling into separate uaccess_* macros
This patch moves the directly coded alternatives for turning PAN on/off
into separate uaccess_{enable,disable} macros or functions. The asm
macros take a few arguments which will be used in subsequent patches.
Note that any (unlikely) access that the compiler might generate between
uaccess_enable() and uaccess_disable(), other than those explicitly
specified by the user access code, will not be protected by PAN.
Cc: Will Deacon <will.deacon@arm.com>
Cc: James Morse <james.morse@arm.com>
Cc: Kees Cook <keescook@chromium.org>
Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Diffstat (limited to 'arch/arm64/lib')
| -rw-r--r-- | arch/arm64/lib/clear_user.S | 11 | ||||
| -rw-r--r-- | arch/arm64/lib/copy_from_user.S | 11 | ||||
| -rw-r--r-- | arch/arm64/lib/copy_in_user.S | 11 | ||||
| -rw-r--r-- | arch/arm64/lib/copy_to_user.S | 11 |
4 files changed, 12 insertions, 32 deletions
diff --git a/arch/arm64/lib/clear_user.S b/arch/arm64/lib/clear_user.S index 5d1cad3ce6d6..d7150e30438a 100644 --- a/arch/arm64/lib/clear_user.S +++ b/arch/arm64/lib/clear_user.S @@ -17,10 +17,7 @@ */ #include <linux/linkage.h> -#include <asm/alternative.h> -#include <asm/assembler.h> -#include <asm/cpufeature.h> -#include <asm/sysreg.h> +#include <asm/uaccess.h> .text @@ -33,8 +30,7 @@ * Alignment fixed up by hardware. */ ENTRY(__clear_user) -ALTERNATIVE("nop", __stringify(SET_PSTATE_PAN(0)), ARM64_ALT_PAN_NOT_UAO, \ - CONFIG_ARM64_PAN) + uaccess_enable_not_uao x2, x3 mov x2, x1 // save the size for fixup return subs x1, x1, #8 b.mi 2f @@ -54,8 +50,7 @@ uao_user_alternative 9f, strh, sttrh, wzr, x0, 2 b.mi 5f uao_user_alternative 9f, strb, sttrb, wzr, x0, 0 5: mov x0, #0 -ALTERNATIVE("nop", __stringify(SET_PSTATE_PAN(1)), ARM64_ALT_PAN_NOT_UAO, \ - CONFIG_ARM64_PAN) + uaccess_disable_not_uao x2 ret ENDPROC(__clear_user) diff --git a/arch/arm64/lib/copy_from_user.S b/arch/arm64/lib/copy_from_user.S index 4fd67ea03bb0..cfe13396085b 100644 --- a/arch/arm64/lib/copy_from_user.S +++ b/arch/arm64/lib/copy_from_user.S @@ -16,11 +16,8 @@ #include <linux/linkage.h> -#include <asm/alternative.h> -#include <asm/assembler.h> #include <asm/cache.h> -#include <asm/cpufeature.h> -#include <asm/sysreg.h> +#include <asm/uaccess.h> /* * Copy from user space to a kernel buffer (alignment handled by the hardware) @@ -67,12 +64,10 @@ end .req x5 ENTRY(__arch_copy_from_user) -ALTERNATIVE("nop", __stringify(SET_PSTATE_PAN(0)), ARM64_ALT_PAN_NOT_UAO, \ - CONFIG_ARM64_PAN) + uaccess_enable_not_uao x3, x4 add end, x0, x2 #include "copy_template.S" -ALTERNATIVE("nop", __stringify(SET_PSTATE_PAN(1)), ARM64_ALT_PAN_NOT_UAO, \ - CONFIG_ARM64_PAN) + uaccess_disable_not_uao x3 mov x0, #0 // Nothing to copy ret ENDPROC(__arch_copy_from_user) diff --git a/arch/arm64/lib/copy_in_user.S b/arch/arm64/lib/copy_in_user.S index f7292dd08c84..718b1c4e2f85 100644 --- a/arch/arm64/lib/copy_in_user.S +++ b/arch/arm64/lib/copy_in_user.S @@ -18,11 +18,8 @@ #include <linux/linkage.h> -#include <asm/alternative.h> -#include <asm/assembler.h> #include <asm/cache.h> -#include <asm/cpufeature.h> -#include <asm/sysreg.h> +#include <asm/uaccess.h> /* * Copy from user space to user space (alignment handled by the hardware) @@ -68,12 +65,10 @@ end .req x5 ENTRY(__copy_in_user) -ALTERNATIVE("nop", __stringify(SET_PSTATE_PAN(0)), ARM64_ALT_PAN_NOT_UAO, \ - CONFIG_ARM64_PAN) + uaccess_enable_not_uao x3, x4 add end, x0, x2 #include "copy_template.S" -ALTERNATIVE("nop", __stringify(SET_PSTATE_PAN(1)), ARM64_ALT_PAN_NOT_UAO, \ - CONFIG_ARM64_PAN) + uaccess_disable_not_uao x3 mov x0, #0 ret ENDPROC(__copy_in_user) diff --git a/arch/arm64/lib/copy_to_user.S b/arch/arm64/lib/copy_to_user.S index 7a7efe255034..e99e31c9acac 100644 --- a/arch/arm64/lib/copy_to_user.S +++ b/arch/arm64/lib/copy_to_user.S @@ -16,11 +16,8 @@ #include <linux/linkage.h> -#include <asm/alternative.h> -#include <asm/assembler.h> #include <asm/cache.h> -#include <asm/cpufeature.h> -#include <asm/sysreg.h> +#include <asm/uaccess.h> /* * Copy to user space from a kernel buffer (alignment handled by the hardware) @@ -66,12 +63,10 @@ end .req x5 ENTRY(__arch_copy_to_user) -ALTERNATIVE("nop", __stringify(SET_PSTATE_PAN(0)), ARM64_ALT_PAN_NOT_UAO, \ - CONFIG_ARM64_PAN) + uaccess_enable_not_uao x3, x4 add end, x0, x2 #include "copy_template.S" -ALTERNATIVE("nop", __stringify(SET_PSTATE_PAN(1)), ARM64_ALT_PAN_NOT_UAO, \ - CONFIG_ARM64_PAN) + uaccess_disable_not_uao x3 mov x0, #0 ret ENDPROC(__arch_copy_to_user) |