diff --git a/arch/arm64/include/asm/thread_info.h b/arch/arm64/include/asm/thread_info.h index 46c3b93cf865..c5ba565544ee 100644 --- a/arch/arm64/include/asm/thread_info.h +++ b/arch/arm64/include/asm/thread_info.h @@ -86,6 +86,7 @@ struct thread_info { #define TIF_NOTIFY_RESUME 2 /* callback before returning to user */ #define TIF_FOREIGN_FPSTATE 3 /* CPU's FP state is not current's */ #define TIF_UPROBE 4 /* uprobe breakpoint or singlestep */ +#define TIF_FSCHECK 5 /* Check FS is USER_DS on return */ #define TIF_NOHZ 7 #define TIF_SYSCALL_TRACE 8 #define TIF_SYSCALL_AUDIT 9 @@ -107,11 +108,12 @@ struct thread_info { #define _TIF_SYSCALL_TRACEPOINT (1 << TIF_SYSCALL_TRACEPOINT) #define _TIF_SECCOMP (1 << TIF_SECCOMP) #define _TIF_UPROBE (1 << TIF_UPROBE) +#define _TIF_FSCHECK (1 << TIF_FSCHECK) #define _TIF_32BIT (1 << TIF_32BIT) #define _TIF_WORK_MASK (_TIF_NEED_RESCHED | _TIF_SIGPENDING | \ _TIF_NOTIFY_RESUME | _TIF_FOREIGN_FPSTATE | \ - _TIF_UPROBE) + _TIF_UPROBE | _TIF_FSCHECK) #define _TIF_SYSCALL_WORK (_TIF_SYSCALL_TRACE | _TIF_SYSCALL_AUDIT | \ _TIF_SYSCALL_TRACEPOINT | _TIF_SECCOMP | \ diff --git a/arch/arm64/include/asm/uaccess.h b/arch/arm64/include/asm/uaccess.h index 7b8a04789cef..ced7a7c2dd41 100644 --- a/arch/arm64/include/asm/uaccess.h +++ b/arch/arm64/include/asm/uaccess.h @@ -45,6 +45,9 @@ static inline void set_fs(mm_segment_t fs) { current_thread_info()->addr_limit = fs; + /* On user-mode return, check fs is correct */ + set_thread_flag(TIF_FSCHECK); + /* * Enable/disable UAO so that copy_to_user() etc can access * kernel memory with the unprivileged instructions. diff --git a/arch/arm64/kernel/signal.c b/arch/arm64/kernel/signal.c index c7b6de62f9d3..0f0279148bdc 100644 --- a/arch/arm64/kernel/signal.c +++ b/arch/arm64/kernel/signal.c @@ -25,6 +25,7 @@ #include #include #include +#include #include #include @@ -408,6 +409,10 @@ asmlinkage void do_notify_resume(struct pt_regs *regs, * Update the trace code with the current status. */ trace_hardirqs_off(); + + /* Check valid user FS if needed */ + addr_limit_user_check(); + do { if (thread_flags & _TIF_NEED_RESCHED) { schedule();