diff options
Diffstat (limited to 'arch/arm64/kernel/process.c')
| -rw-r--r-- | arch/arm64/kernel/process.c | 19 |
1 files changed, 19 insertions, 0 deletions
diff --git a/arch/arm64/kernel/process.c b/arch/arm64/kernel/process.c index 88d742ba19d5..c1ca4ea065d4 100644 --- a/arch/arm64/kernel/process.c +++ b/arch/arm64/kernel/process.c @@ -46,6 +46,7 @@ #include <linux/notifier.h> #include <trace/events/power.h> +#include <asm/alternative.h> #include <asm/compat.h> #include <asm/cacheflush.h> #include <asm/fpsimd.h> @@ -280,6 +281,9 @@ int copy_thread(unsigned long clone_flags, unsigned long stack_start, } else { memset(childregs, 0, sizeof(struct pt_regs)); childregs->pstate = PSR_MODE_EL1h; + if (IS_ENABLED(CONFIG_ARM64_UAO) && + cpus_have_cap(ARM64_HAS_UAO)) + childregs->pstate |= PSR_UAO_BIT; p->thread.cpu_context.x19 = stack_start; p->thread.cpu_context.x20 = stk_sz; } @@ -308,6 +312,20 @@ static void tls_thread_switch(struct task_struct *next) : : "r" (tpidr), "r" (tpidrro)); } +/* Restore the UAO state depending on next's addr_limit */ +static void uao_thread_switch(struct task_struct *next) +{ + unsigned long next_sp = next->thread.cpu_context.sp; + + if (IS_ENABLED(CONFIG_ARM64_UAO) && + get_thread_info(next_sp)->addr_limit == KERNEL_DS) + asm(ALTERNATIVE("nop", SET_PSTATE_UAO(1), ARM64_HAS_UAO, + CONFIG_ARM64_UAO)); + else + asm(ALTERNATIVE("nop", SET_PSTATE_UAO(0), ARM64_HAS_UAO, + CONFIG_ARM64_UAO)); +} + /* * Thread switching. */ @@ -320,6 +338,7 @@ struct task_struct *__switch_to(struct task_struct *prev, tls_thread_switch(next); hw_breakpoint_thread_switch(next); contextidr_thread_switch(next); + uao_thread_switch(next); /* * Complete any pending TLB or cache maintenance on this CPU in case |