x86/fpu: Use the correct exception table macro in the XSTATE_OP wrapper

Commit

  75045f77f7a7 ("x86/extable: Introduce _ASM_EXTABLE_UA for uaccess fixups")

incorrectly replaced the fixup entry for XSTATE_OP with a user-#PF-only
fixup. XRSTOR can also raise #GP if the xstate content is invalid,
and _ASM_EXTABLE_UA doesn't expect that. Change this fixup back to
_ASM_EXTABLE so that #GP gets fixed up.

Fixes: 75045f77f7a7 ("x86/extable: Introduce _ASM_EXTABLE_UA for uaccess fixups")
Reported-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Jann Horn <jannh@google.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Acked-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Tested-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: "Naveen N. Rao" <naveen.n.rao@linux.vnet.ibm.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: kernel-hardening@lists.openwall.com
Cc: x86-ml <x86@kernel.org>
Link: https://lkml.kernel.org/r/20181126165957.xhsyu2dhyy45mrjo@linutronix.de
Link: https://lkml.kernel.org/r/20181127133200.38322-1-jannh@google.com

diff --git a/arch/x86/include/asm/fpu/internal.h b/arch/x86/include/asm/fpu/internal.h
index 5f7290e..69dcdf1 100644 (file)
--- a/arch/x86/include/asm/fpu/internal.h
+++ b/arch/x86/include/asm/fpu/internal.h
@@ -226,7 +226,7 @@ static inline void copy_fxregs_to_kernel(struct fpu *fpu)
                     "3: movl $-2,%[err]\n\t"                           \
                     "jmp 2b\n\t"                                       \
                     ".popsection\n\t"                                  \
-                    _ASM_EXTABLE_UA(1b, 3b)                            \
+                    _ASM_EXTABLE(1b, 3b)                               \
                     : [err] "=r" (err)                                 \
                     : "D" (st), "m" (*st), "a" (lmask), "d" (hmask)    \
                     : "memory")