sh: Fixup __strnlen_user() behaviour.

Drop TIF_USERSPACE and add addr_limit to the thread_info struct.
Subsequently, use that for address checking in strnlen_user() to
ward off bogus -EFAULTs.

Make __strnlen_user() return 0 on exception, rather than -EFAULT.

Signed-off-by: Paul Mundt <lethal@linux-sh.org>

1 files changed, 2 insertions, 2 deletions

diff --git a/include/asm-sh/thread_info.h b/include/asm-sh/thread_info.h
index f64dd803a014..b986a1914472 100644
--- a/include/asm-sh/thread_info.h
+++ b/include/asm-sh/thread_info.h
@@ -21,6 +21,7 @@ struct thread_info {
         unsigned long           flags;          /* low level flags */
         __u32                   cpu;
         int                     preempt_count; /* 0 => preemptable, <0 => BUG */
+        mm_segment_t            addr_limit;     /* thread address space */
         struct restart_block    restart_block;
         __u8                    supervisor_stack[0];
 };
@@ -40,6 +41,7 @@ struct thread_info {
         .flags          = 0,                    \
         .cpu            = 0,                    \
         .preempt_count  = 1,                    \
+        .addr_limit     = KERNEL_DS,            \
         .restart_block  = {                     \
                 .fn = do_no_restart_syscall,    \
         },                                      \
@@ -95,7 +97,6 @@ static inline struct thread_info *current_thread_info(void)
 #define TIF_USEDFPU             16      /* FPU was used by this task this quantum (SMP) */
 #define TIF_POLLING_NRFLAG      17      /* true if poll_idle() is polling TIF_NEED_RESCHED */
 #define TIF_MEMDIE              18
-#define TIF_USERSPACE           31      /* true if FS sets userspace */
 
 #define _TIF_SYSCALL_TRACE      (1<<TIF_SYSCALL_TRACE)
 #define _TIF_NOTIFY_RESUME      (1<<TIF_NOTIFY_RESUME)
@@ -103,7 +104,6 @@ static inline struct thread_info *current_thread_info(void)
 #define _TIF_NEED_RESCHED       (1<<TIF_NEED_RESCHED)
 #define _TIF_USEDFPU            (1<<TIF_USEDFPU)
 #define _TIF_POLLING_NRFLAG     (1<<TIF_POLLING_NRFLAG)
-#define _TIF_USERSPACE          (1<<TIF_USERSPACE)
 
 #define _TIF_WORK_MASK          0x000000FE      /* work to do on interrupt/exception return */
 #define _TIF_ALLWORK_MASK       0x000000FF      /* work to do on any return to u-space */