[PATCH] x32: make sure TS_COMPAT is cleared for x32 tasks

[Bobby Powers <bobbypowers@gmail.com>]

If a process has a non-x32 ia32 personality and changes to x32, the
process would keep its TS_COMPAT flag. x32 uses the presence of the
x32 flag on a syscall to determine compat status, so make sure
TS_COMPAT is cleared.

Signed-off-by: Bobby Powers <bobbypowers@gmail.com>
---
 arch/x86/kernel/process_64.c |    3 +++
 1 files changed, 3 insertions(+), 0 deletions(-)

diff --git a/arch/x86/kernel/process_64.c b/arch/x86/kernel/process_64.c
index e9ec8f1..a465973 100644
--- a/arch/x86/kernel/process_64.c
+++ b/arch/x86/kernel/process_64.c
@@ -539,6 +539,9 @@ void set_personality_ia32(bool x32)
 		clear_thread_flag(TIF_IA32);
 		set_thread_flag(TIF_X32);
 		current->personality &= ~READ_IMPLIES_EXEC;
+		/* is_compat_task() uses the presence of the x32
+		   syscall bit flag to determine compat status */
+		current_thread_info()->status &= ~TS_COMPAT;
 	} else {
 		set_thread_flag(TIF_IA32);
 		clear_thread_flag(TIF_X32);
-- 
1.7.7.6