diff options
| author | Catalin Marinas <catalin.marinas@arm.com> | 2016-07-01 14:58:21 +0100 |
|---|---|---|
| committer | Sami Tolvanen <samitolvanen@google.com> | 2016-09-29 10:52:56 -0700 |
| commit | 23368b642deb01ac6ce668ec1dedfcc0cab25c71 (patch) | |
| tree | cfd149ddb906f10eaac9525473e97593a2e19343 /arch/arm64/kernel | |
| parent | d907eb252977469ed9bded38bd76c2212065c2cf (diff) | |
FROMLIST: 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>
Cc: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Change-Id: Ic3fddd706400c8798f57456c56361d84d234f6ef
(cherry picked from commit a4820644c627b82cbc865f2425bb788c94743b16)
Signed-off-by: Sami Tolvanen <samitolvanen@google.com>
Diffstat (limited to 'arch/arm64/kernel')
| -rw-r--r-- | arch/arm64/kernel/armv8_deprecated.c | 10 |
1 files changed, 5 insertions, 5 deletions
diff --git a/arch/arm64/kernel/armv8_deprecated.c b/arch/arm64/kernel/armv8_deprecated.c index c37202c0c838..562f7ddb158b 100644 --- a/arch/arm64/kernel/armv8_deprecated.c +++ b/arch/arm64/kernel/armv8_deprecated.c @@ -281,9 +281,9 @@ static void __init register_insn_emulation_sysctl(struct ctl_table *table) * Error-checking SWP macros implemented using ldxr{b}/stxr{b} */ #define __user_swpX_asm(data, addr, res, temp, B) \ +do { \ + uaccess_enable(); \ __asm__ __volatile__( \ - ALTERNATIVE("nop", SET_PSTATE_PAN(0), ARM64_HAS_PAN, \ - CONFIG_ARM64_PAN) \ "0: ldxr"B" %w2, [%3]\n" \ "1: stxr"B" %w0, %w1, [%3]\n" \ " cbz %w0, 2f\n" \ @@ -299,11 +299,11 @@ static void __init register_insn_emulation_sysctl(struct ctl_table *table) " .popsection" \ _ASM_EXTABLE(0b, 4b) \ _ASM_EXTABLE(1b, 4b) \ - ALTERNATIVE("nop", SET_PSTATE_PAN(1), ARM64_HAS_PAN, \ - CONFIG_ARM64_PAN) \ : "=&r" (res), "+r" (data), "=&r" (temp) \ : "r" (addr), "i" (-EAGAIN), "i" (-EFAULT) \ - : "memory") + : "memory"); \ + uaccess_disable(); \ +} while (0) #define __user_swp_asm(data, addr, res, temp) \ __user_swpX_asm(data, addr, res, temp, "") |