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Groups > linux.kernel > #1397395

[PATCH v5 10/13] x86/xsaves: Fix __fpu_restore_sig() for XSAVES

From Yu-cheng Yu <yu-cheng.yu@intel.com>
Newsgroups linux.kernel
Subject [PATCH v5 10/13] x86/xsaves: Fix __fpu_restore_sig() for XSAVES
Date 2016-05-09 23:00 +0200
Message-ID <rx0ry-4yi-49@gated-at.bofh.it> (permalink)
References <rx0rx-4yi-11@gated-at.bofh.it>
Organization linux.* mail to news gateway

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When the kernel is using XSAVES compacted format, we cannot do
__copy_from_user() from a signal frame, which has standard-format data.
Fix it by using copyin_to_xsaves().

Signed-off-by: Yu-cheng Yu <yu-cheng.yu@intel.com>
---
 arch/x86/kernel/fpu/signal.c | 11 +++++++++--
 1 file changed, 9 insertions(+), 2 deletions(-)

diff --git a/arch/x86/kernel/fpu/signal.c b/arch/x86/kernel/fpu/signal.c
index d7fdd8c..9c2ff42 100644
--- a/arch/x86/kernel/fpu/signal.c
+++ b/arch/x86/kernel/fpu/signal.c
@@ -320,8 +320,15 @@ static int __fpu__restore_sig(void __user *buf, void __user *buf_fx, int size)
 		 */
 		fpu__drop(fpu);
 
-		if (__copy_from_user(&fpu->state.xsave, buf_fx, state_size) ||
-		    __copy_from_user(&env, buf, sizeof(env))) {
+		if (using_compacted_format()) {
+			err = copyin_to_xsaves(NULL, buf_fx,
+					       &fpu->state.xsave);
+		} else {
+			err = __copy_from_user(&fpu->state.xsave,
+					       buf_fx, state_size);
+		}
+
+		if (err || __copy_from_user(&env, buf, sizeof(env))) {
 			fpstate_init(&fpu->state);
 			err = -1;
 		} else {
-- 
1.9.1

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[PATCH v5 10/13] x86/xsaves: Fix __fpu_restore_sig() for XSAVES Yu-cheng Yu <yu-cheng.yu@intel.com> - 2016-05-09 23:00 +0200
  Re: [PATCH v5 10/13] x86/xsaves: Fix __fpu_restore_sig() for XSAVES Dave Hansen <dave.hansen@linux.intel.com> - 2016-05-10 01:50 +0200

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