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>
diff --git a/include/asm-sh/thread_info.h b/include/asm-sh/thread_info.h
index f64dd80..b986a19 100644
--- a/include/asm-sh/thread_info.h
+++ b/include/asm-sh/thread_info.h
@@ -21,6 +21,7 @@
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 @@
.flags = 0, \
.cpu = 0, \
.preempt_count = 1, \
+ .addr_limit = KERNEL_DS, \
.restart_block = { \
.fn = do_no_restart_syscall, \
}, \
@@ -95,7 +97,6 @@
#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 @@
#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 */