[PATCH 3/3] x86_64, copy_thread: Fix CLONE_SETTLS bitness

From: Andy Lutomirski
Date: Tue Feb 24 2015 - 19:02:03 EST


CLONE_SETTLS is expected to write a TLS entry in the GDT for 32-bit
callers and to set fsbase for 64-bit callers.

The correct check is is_ia32_task(), which returns true in the
context of a 32-bit syscall. TIF_IA32 is set if the task itself has
a 32-bit personality, which is not the same thing.

Signed-off-by: Andy Lutomirski <luto@xxxxxxxxxxxxxx>
---
arch/x86/kernel/process_64.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/x86/kernel/process_64.c b/arch/x86/kernel/process_64.c
index 5a2c02913af3..936d43461dca 100644
--- a/arch/x86/kernel/process_64.c
+++ b/arch/x86/kernel/process_64.c
@@ -207,7 +207,7 @@ int copy_thread(unsigned long clone_flags, unsigned long sp,
*/
if (clone_flags & CLONE_SETTLS) {
#ifdef CONFIG_IA32_EMULATION
- if (test_thread_flag(TIF_IA32))
+ if (is_ia32_task())
err = do_set_thread_area(p, -1,
(struct user_desc __user *)childregs->si, 0);
else
--
2.3.0

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