diff options
| author | James Morse <james.morse@arm.com> | 2015-07-22 19:05:54 +0100 |
|---|---|---|
| committer | Will Deacon <will.deacon@arm.com> | 2015-07-27 11:08:41 +0100 |
| commit | 338d4f49d6f7114a017d294ccf7374df4f998edc (patch) | |
| tree | af0b5cedc6e042623346d4e82be24eda190626a1 /arch/arm64/include/asm/sysreg.h | |
| parent | 9ded63aaf83eba76e1a54ac02581c2badc497f1a (diff) | |
arm64: kernel: Add support for Privileged Access Never
'Privileged Access Never' is a new arm8.1 feature which prevents
privileged code from accessing any virtual address where read or write
access is also permitted at EL0.
This patch enables the PAN feature on all CPUs, and modifies {get,put}_user
helpers temporarily to permit access.
This will catch kernel bugs where user memory is accessed directly.
'Unprivileged loads and stores' using ldtrb et al are unaffected by PAN.
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: James Morse <james.morse@arm.com>
[will: use ALTERNATIVE in asm and tidy up pan_enable check]
Signed-off-by: Will Deacon <will.deacon@arm.com>
Diffstat (limited to 'arch/arm64/include/asm/sysreg.h')
| -rw-r--r-- | arch/arm64/include/asm/sysreg.h | 8 |
1 files changed, 8 insertions, 0 deletions
diff --git a/arch/arm64/include/asm/sysreg.h b/arch/arm64/include/asm/sysreg.h index 5295bcbcb374..a7f3d4b2514d 100644 --- a/arch/arm64/include/asm/sysreg.h +++ b/arch/arm64/include/asm/sysreg.h @@ -20,6 +20,8 @@ #ifndef __ASM_SYSREG_H #define __ASM_SYSREG_H +#include <asm/opcodes.h> + #define SCTLR_EL1_CP15BEN (0x1 << 5) #define SCTLR_EL1_SED (0x1 << 8) @@ -36,6 +38,12 @@ #define sys_reg(op0, op1, crn, crm, op2) \ ((((op0)&3)<<19)|((op1)<<16)|((crn)<<12)|((crm)<<8)|((op2)<<5)) +#define REG_PSTATE_PAN_IMM sys_reg(0, 0, 4, 0, 4) +#define SCTLR_EL1_SPAN (1 << 23) + +#define SET_PSTATE_PAN(x) __inst_arm(0xd5000000 | REG_PSTATE_PAN_IMM |\ + (!!x)<<8 | 0x1f) + #ifdef __ASSEMBLY__ .irp num,0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,27,28,29,30 |