8 files changed, 348 insertions, 484 deletions

diff --git a/arch/x86/ia32/ia32_signal.c b/arch/x86/ia32/ia32_signal.c
index 452d4dd0a95a..8c77c64fbd27 100644
--- a/arch/x86/ia32/ia32_signal.c
+++ b/arch/x86/ia32/ia32_signal.c
@@ -251,7 +251,7 @@ static int ia32_restore_sigcontext(struct pt_regs *regs,
 
                 get_user_ex(tmp, &sc->fpstate);
                 buf = compat_ptr(tmp);
-                err |= restore_i387_xstate_ia32(buf);
+                err |= restore_xstate_sig(buf, 1);
 
                 get_user_ex(*pax, &sc->ax);
         } get_user_catch(err);
@@ -382,9 +382,12 @@ static void __user *get_sigframe(struct k_sigaction *ka, struct pt_regs *regs,
                 sp = (unsigned long) ka->sa.sa_restorer;
 
         if (used_math()) {
-                sp = sp - sig_xstate_ia32_size;
+                unsigned long fx_aligned, math_size;
+
+                sp = alloc_mathframe(sp, 1, &fx_aligned, &math_size);
                 *fpstate = (struct _fpstate_ia32 __user *) sp;
-                if (save_i387_xstate_ia32(*fpstate) < 0)
+                if (save_xstate_sig(*fpstate, (void __user *)fx_aligned,
+                                    math_size) < 0)
                         return (void __user *) -1L;
         }
 
diff --git a/arch/x86/include/asm/fpu-internal.h b/arch/x86/include/asm/fpu-internal.h
index 016acb30fa4a..4fbb4195bc63 100644
--- a/arch/x86/include/asm/fpu-internal.h
+++ b/arch/x86/include/asm/fpu-internal.h
@@ -22,11 +22,30 @@
 #include <asm/uaccess.h>
 #include <asm/xsave.h>
 
-extern unsigned int sig_xstate_size;
+#ifdef CONFIG_X86_64
+# include <asm/sigcontext32.h>
+# include <asm/user32.h>
+int ia32_setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info,
+                        compat_sigset_t *set, struct pt_regs *regs);
+int ia32_setup_frame(int sig, struct k_sigaction *ka,
+                     compat_sigset_t *set, struct pt_regs *regs);
+#else
+# define user_i387_ia32_struct  user_i387_struct
+# define user32_fxsr_struct     user_fxsr_struct
+# define ia32_setup_frame       __setup_frame
+# define ia32_setup_rt_frame    __setup_rt_frame
+#endif
+
+extern unsigned int mxcsr_feature_mask;
 extern void fpu_init(void);
 
 DECLARE_PER_CPU(struct task_struct *, fpu_owner_task);
 
+extern void convert_from_fxsr(struct user_i387_ia32_struct *env,
+                              struct task_struct *tsk);
+extern void convert_to_fxsr(struct task_struct *tsk,
+                            const struct user_i387_ia32_struct *env);
+
 extern user_regset_active_fn fpregs_active, xfpregs_active;
 extern user_regset_get_fn fpregs_get, xfpregs_get, fpregs_soft_get,
                                 xstateregs_get;
@@ -39,19 +58,11 @@ extern user_regset_set_fn fpregs_set, xfpregs_set, fpregs_soft_set,
  */
 #define xstateregs_active       fpregs_active
 
-extern struct _fpx_sw_bytes fx_sw_reserved;
-#ifdef CONFIG_IA32_EMULATION
-extern unsigned int sig_xstate_ia32_size;
-extern struct _fpx_sw_bytes fx_sw_reserved_ia32;
-struct _fpstate_ia32;
-struct _xstate_ia32;
-extern int save_i387_xstate_ia32(void __user *buf);
-extern int restore_i387_xstate_ia32(void __user *buf);
-#endif
-
 #ifdef CONFIG_MATH_EMULATION
+# define HAVE_HWFP              (boot_cpu_data.hard_math)
 extern void finit_soft_fpu(struct i387_soft_struct *soft);
 #else
+# define HAVE_HWFP              1
 static inline void finit_soft_fpu(struct i387_soft_struct *soft) {}
 #endif
 
@@ -119,17 +130,6 @@ static inline int fsave_user(struct i387_fsave_struct __user *fx)
 
 static inline int fxsave_user(struct i387_fxsave_struct __user *fx)
 {
-        int err;
-
-        /*
-         * Clear the bytes not touched by the fxsave and reserved
-         * for the SW usage.
-         */
-        err = __clear_user(&fx->sw_reserved,
-                           sizeof(struct _fpx_sw_bytes));
-        if (unlikely(err))
-                return -EFAULT;
-
         if (config_enabled(CONFIG_X86_32))
                 return check_insn(fxsave %[fx], [fx] "=m" (*fx), "m" (*fx));
         else if (config_enabled(CONFIG_AS_FXSAVEQ))
@@ -189,19 +189,6 @@ static inline void fpu_fxsave(struct fpu *fpu)
                              : [fx] "R" (&fpu->state->fxsave));
         }
 }
-#ifdef CONFIG_X86_64
-
-int ia32_setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info,
-                        compat_sigset_t *set, struct pt_regs *regs);
-int ia32_setup_frame(int sig, struct k_sigaction *ka,
-                     compat_sigset_t *set, struct pt_regs *regs);
-
-#else  /* CONFIG_X86_32 */
-
-#define ia32_setup_frame        __setup_frame
-#define ia32_setup_rt_frame     __setup_rt_frame
-
-#endif  /* CONFIG_X86_64 */
 
 /*
  * These must be called with preempt disabled. Returns
@@ -392,10 +379,28 @@ static inline void switch_fpu_finish(struct task_struct *new, fpu_switch_t fpu)
 /*
  * Signal frame handlers...
  */
-extern int save_i387_xstate(void __user *buf);
-extern int restore_i387_xstate(void __user *buf);
+extern int save_xstate_sig(void __user *buf, void __user *fx, int size);
+extern int __restore_xstate_sig(void __user *buf, void __user *fx, int size);
+
+static inline int xstate_sigframe_size(void)
+{
+        return use_xsave() ? xstate_size + FP_XSTATE_MAGIC2_SIZE : xstate_size;
+}
+
+static inline int restore_xstate_sig(void __user *buf, int ia32_frame)
+{
+        void __user *buf_fx = buf;
+        int size = xstate_sigframe_size();
+
+        if (ia32_frame && use_fxsr()) {
+                buf_fx = buf + sizeof(struct i387_fsave_struct);
+                size += sizeof(struct i387_fsave_struct);
+        }
+
+        return __restore_xstate_sig(buf, buf_fx, size);
+}
 
-static inline void __clear_fpu(struct task_struct *tsk)
+static inline void __drop_fpu(struct task_struct *tsk)
 {
         if (__thread_has_fpu(tsk)) {
                 /* Ignore delayed exceptions from user space */
@@ -443,11 +448,21 @@ static inline void save_init_fpu(struct task_struct *tsk)
         preempt_enable();
 }
 
-static inline void clear_fpu(struct task_struct *tsk)
+static inline void stop_fpu_preload(struct task_struct *tsk)
 {
+        tsk->fpu_counter = 0;
+}
+
+static inline void drop_fpu(struct task_struct *tsk)
+{
+        /*
+         * Forget coprocessor state..
+         */
+        stop_fpu_preload(tsk);
         preempt_disable();
-        __clear_fpu(tsk);
+        __drop_fpu(tsk);
         preempt_enable();
+        clear_used_math();
 }
 
 /*
@@ -511,4 +526,20 @@ static inline void fpu_copy(struct fpu *dst, struct fpu *src)
 
 extern void fpu_finit(struct fpu *fpu);
 
+static inline unsigned long
+alloc_mathframe(unsigned long sp, int ia32_frame, unsigned long *buf_fx,
+                unsigned long *size)
+{
+        unsigned long frame_size = xstate_sigframe_size();
+
+        *buf_fx = sp = round_down(sp - frame_size, 64);
+        if (ia32_frame && use_fxsr()) {
+                frame_size += sizeof(struct i387_fsave_struct);
+                sp -= sizeof(struct i387_fsave_struct);
+        }
+
+        *size = frame_size;
+        return sp;
+}
+
 #endif
diff --git a/arch/x86/include/asm/xsave.h b/arch/x86/include/asm/xsave.h
index aaac810e8613..c1d989a15193 100644
--- a/arch/x86/include/asm/xsave.h
+++ b/arch/x86/include/asm/xsave.h
@@ -38,9 +38,6 @@ extern u64 xstate_fx_sw_bytes[USER_XSTATE_FX_SW_WORDS];
 extern void xsave_init(void);
 extern void update_regset_xstate_info(unsigned int size, u64 xstate_mask);
 extern int init_fpu(struct task_struct *child);
-extern int check_for_xstate(struct i387_fxsave_struct __user *buf,
-                            void __user *fpstate,
-                            struct _fpx_sw_bytes *sw);
 
 static inline int fpu_xrstor_checking(struct xsave_struct *fx)
 {
@@ -68,8 +65,7 @@ static inline int xsave_user(struct xsave_struct __user *buf)
          * Clear the xsave header first, so that reserved fields are
          * initialized to zero.
          */
-        err = __clear_user(&buf->xsave_hdr,
-                           sizeof(struct xsave_hdr_struct));
+        err = __clear_user(&buf->xsave_hdr, sizeof(buf->xsave_hdr));
         if (unlikely(err))
                 return -EFAULT;
 
diff --git a/arch/x86/kernel/i387.c b/arch/x86/kernel/i387.c
index f250431fb505..ab6a2e8028ae 100644
--- a/arch/x86/kernel/i387.c
+++ b/arch/x86/kernel/i387.c
@@ -19,20 +19,6 @@
 #include <asm/fpu-internal.h>
 #include <asm/user.h>
 
-#ifdef CONFIG_X86_64
-# include <asm/sigcontext32.h>
-# include <asm/user32.h>
-#else
-# define save_i387_xstate_ia32          save_i387_xstate
-# define restore_i387_xstate_ia32       restore_i387_xstate
-# define _fpstate_ia32          _fpstate
-# define _xstate_ia32           _xstate
-# define sig_xstate_ia32_size   sig_xstate_size
-# define fx_sw_reserved_ia32    fx_sw_reserved
-# define user_i387_ia32_struct  user_i387_struct
-# define user32_fxsr_struct     user_fxsr_struct
-#endif
-
 /*
  * Were we in an interrupt that interrupted kernel mode?
  *
@@ -113,16 +99,9 @@ void unlazy_fpu(struct task_struct *tsk)
 }
 EXPORT_SYMBOL(unlazy_fpu);
 
-#ifdef CONFIG_MATH_EMULATION
-# define HAVE_HWFP              (boot_cpu_data.hard_math)
-#else
-# define HAVE_HWFP              1
-#endif
-
-static unsigned int             mxcsr_feature_mask __read_mostly = 0xffffffffu;
+unsigned int mxcsr_feature_mask __read_mostly = 0xffffffffu;
 unsigned int xstate_size;
 EXPORT_SYMBOL_GPL(xstate_size);
-unsigned int sig_xstate_ia32_size = sizeof(struct _fpstate_ia32);
 static struct i387_fxsave_struct fx_scratch __cpuinitdata;
 
 static void __cpuinit mxcsr_feature_mask_init(void)
@@ -454,7 +433,7 @@ static inline u32 twd_fxsr_to_i387(struct i387_fxsave_struct *fxsave)
  * FXSR floating point environment conversions.
  */
 
-static void
+void
 convert_from_fxsr(struct user_i387_ia32_struct *env, struct task_struct *tsk)
 {
         struct i387_fxsave_struct *fxsave = &tsk->thread.fpu.state->fxsave;
@@ -491,8 +470,8 @@ convert_from_fxsr(struct user_i387_ia32_struct *env, struct task_struct *tsk)
                 memcpy(&to[i], &from[i], sizeof(to[0]));
 }
 
-static void convert_to_fxsr(struct task_struct *tsk,
-                            const struct user_i387_ia32_struct *env)
+void convert_to_fxsr(struct task_struct *tsk,
+                     const struct user_i387_ia32_struct *env)
 
 {
         struct i387_fxsave_struct *fxsave = &tsk->thread.fpu.state->fxsave;
@@ -589,223 +568,6 @@ int fpregs_set(struct task_struct *target, const struct user_regset *regset,
 }
 
 /*
- * Signal frame handlers.
- */
-
-static inline int save_i387_fsave(struct _fpstate_ia32 __user *buf)
-{
-        struct task_struct *tsk = current;
-        struct i387_fsave_struct *fp = &tsk->thread.fpu.state->fsave;
-
-        fp->status = fp->swd;
-        if (__copy_to_user(buf, fp, sizeof(struct i387_fsave_struct)))
-                return -1;
-        return 1;
-}
-
-static int save_i387_fxsave(struct _fpstate_ia32 __user *buf)
-{
-        struct task_struct *tsk = current;
-        struct i387_fxsave_struct *fx = &tsk->thread.fpu.state->fxsave;
-        struct user_i387_ia32_struct env;
-        int err = 0;
-
-        convert_from_fxsr(&env, tsk);
-        if (__copy_to_user(buf, &env, sizeof(env)))
-                return -1;
-
-        err |= __put_user(fx->swd, &buf->status);
-        err |= __put_user(X86_FXSR_MAGIC, &buf->magic);
-        if (err)
-                return -1;
-
-        if (__copy_to_user(&buf->_fxsr_env[0], fx, xstate_size))
-                return -1;
-        return 1;
-}
-
-static int save_i387_xsave(void __user *buf)
-{
-        struct task_struct *tsk = current;
-        struct _fpstate_ia32 __user *fx = buf;
-        int err = 0;
-
-
-        sanitize_i387_state(tsk);
-
-        /*
-         * For legacy compatible, we always set FP/SSE bits in the bit
-         * vector while saving the state to the user context.
-         * This will enable us capturing any changes(during sigreturn) to
-         * the FP/SSE bits by the legacy applications which don't touch
-         * xstate_bv in the xsave header.
-         *
-         * xsave aware applications can change the xstate_bv in the xsave
-         * header as well as change any contents in the memory layout.
-         * xrestore as part of sigreturn will capture all the changes.
-         */
-        tsk->thread.fpu.state->xsave.xsave_hdr.xstate_bv |= XSTATE_FPSSE;
-
-        if (save_i387_fxsave(fx) < 0)
-                return -1;
-
-        err = __copy_to_user(&fx->sw_reserved, &fx_sw_reserved_ia32,
-                             sizeof(struct _fpx_sw_bytes));
-        err |= __put_user(FP_XSTATE_MAGIC2,
-                          (__u32 __user *) (buf + sig_xstate_ia32_size
-                                            - FP_XSTATE_MAGIC2_SIZE));
-        if (err)
-                return -1;
-
-        return 1;
-}
-
-int save_i387_xstate_ia32(void __user *buf)
-{
-        struct _fpstate_ia32 __user *fp = (struct _fpstate_ia32 __user *) buf;
-        struct task_struct *tsk = current;
-
-        if (!used_math())
-                return 0;
-
-        if (!access_ok(VERIFY_WRITE, buf, sig_xstate_ia32_size))
-                return -EACCES;
-        /*
-         * This will cause a "finit" to be triggered by the next
-         * attempted FPU operation by the 'current' process.
-         */
-        clear_used_math();
-
-        if (!HAVE_HWFP) {
-                return fpregs_soft_get(current, NULL,
-                                       0, sizeof(struct user_i387_ia32_struct),
-                                       NULL, fp) ? -1 : 1;
-        }
-
-        unlazy_fpu(tsk);
-
-        if (cpu_has_xsave)
-                return save_i387_xsave(fp);
-        if (cpu_has_fxsr)
-                return save_i387_fxsave(fp);
-        else
-                return save_i387_fsave(fp);
-}
-
-static inline int restore_i387_fsave(struct _fpstate_ia32 __user *buf)
-{
-        struct task_struct *tsk = current;
-
-        return __copy_from_user(&tsk->thread.fpu.state->fsave, buf,
-                                sizeof(struct i387_fsave_struct));
-}
-
-static int restore_i387_fxsave(struct _fpstate_ia32 __user *buf,
-                               unsigned int size)
-{
-        struct task_struct *tsk = current;
-        struct user_i387_ia32_struct env;
-        int err;
-
-        err = __copy_from_user(&tsk->thread.fpu.state->fxsave, &buf->_fxsr_env[0],
-                               size);
-        /* mxcsr reserved bits must be masked to zero for security reasons */
-        tsk->thread.fpu.state->fxsave.mxcsr &= mxcsr_feature_mask;
-        if (err || __copy_from_user(&env, buf, sizeof(env)))
-                return 1;
-        convert_to_fxsr(tsk, &env);
-
-        return 0;
-}
-
-static int restore_i387_xsave(void __user *buf)
-{
-        struct _fpx_sw_bytes fx_sw_user;
-        struct _fpstate_ia32 __user *fx_user =
-                        ((struct _fpstate_ia32 __user *) buf);
-        struct i387_fxsave_struct __user *fx =
-                (struct i387_fxsave_struct __user *) &fx_user->_fxsr_env[0];
-        struct xsave_hdr_struct *xsave_hdr =
-                                &current->thread.fpu.state->xsave.xsave_hdr;
-        u64 mask;
-        int err;
-
-        if (check_for_xstate(fx, buf, &fx_sw_user))
-                goto fx_only;
-
-        mask = fx_sw_user.xstate_bv;
-
-        err = restore_i387_fxsave(buf, fx_sw_user.xstate_size);
-
-        xsave_hdr->xstate_bv &= pcntxt_mask;
-        /*
-         * These bits must be zero.
-         */
-        xsave_hdr->reserved1[0] = xsave_hdr->reserved1[1] = 0;
-
-        /*
-         * Init the state that is not present in the memory layout
-         * and enabled by the OS.
-         */
-        mask = ~(pcntxt_mask & ~mask);
-        xsave_hdr->xstate_bv &= mask;
-
-        return err;
-fx_only:
-        /*
-         * Couldn't find the extended state information in the memory
-         * layout. Restore the FP/SSE and init the other extended state
-         * enabled by the OS.
-         */
-        xsave_hdr->xstate_bv = XSTATE_FPSSE;
-        return restore_i387_fxsave(buf, sizeof(struct i387_fxsave_struct));
-}
-
-int restore_i387_xstate_ia32(void __user *buf)
-{
-        int err;
-        struct task_struct *tsk = current;
-        struct _fpstate_ia32 __user *fp = (struct _fpstate_ia32 __user *) buf;
-
-        if (HAVE_HWFP)
-                clear_fpu(tsk);
-
-        if (!buf) {
-                if (used_math()) {
-                        clear_fpu(tsk);
-                        clear_used_math();
-                }
-
-                return 0;
-        } else
-                if (!access_ok(VERIFY_READ, buf, sig_xstate_ia32_size))
-                        return -EACCES;
-
-        if (!used_math()) {
-                err = init_fpu(tsk);
-                if (err)
-                        return err;
-        }
-
-        if (HAVE_HWFP) {
-                if (cpu_has_xsave)
-                        err = restore_i387_xsave(buf);
-                else if (cpu_has_fxsr)
-                        err = restore_i387_fxsave(fp, sizeof(struct
-                                                           i387_fxsave_struct));
-                else
-                        err = restore_i387_fsave(fp);
-        } else {
-                err = fpregs_soft_set(current, NULL,
-                                      0, sizeof(struct user_i387_ia32_struct),
-                                      NULL, fp) != 0;
-        }
-        set_used_math();
-
-        return err;
-}
-
-/*
  * FPU state for core dumps.
  * This is only used for a.out dumps now.
  * It is declared generically using elf_fpregset_t (which is
diff --git a/arch/x86/kernel/process.c b/arch/x86/kernel/process.c
index ef6a8456f719..30069d1a6a4d 100644
--- a/arch/x86/kernel/process.c
+++ b/arch/x86/kernel/process.c
@@ -97,16 +97,6 @@ void arch_task_cache_init(void)
                                   SLAB_PANIC | SLAB_NOTRACK, NULL);
 }
 
-static inline void drop_fpu(struct task_struct *tsk)
-{
-        /*
-         * Forget coprocessor state..
-         */
-        tsk->fpu_counter = 0;
-        clear_fpu(tsk);
-        clear_used_math();
-}
-
 /*
  * Free current thread data structures etc..
  */
diff --git a/arch/x86/kernel/ptrace.c b/arch/x86/kernel/ptrace.c
index c4c6a5c2bf0f..861a9d1a463d 100644
--- a/arch/x86/kernel/ptrace.c
+++ b/arch/x86/kernel/ptrace.c
@@ -1332,9 +1332,6 @@ static const struct user_regset_view user_x86_64_view = {
 #define genregs32_get           genregs_get
 #define genregs32_set           genregs_set
 
-#define user_i387_ia32_struct   user_i387_struct
-#define user32_fxsr_struct      user_fxsr_struct
-
 #endif  /* CONFIG_X86_64 */
 
 #if defined CONFIG_X86_32 || defined CONFIG_IA32_EMULATION
diff --git a/arch/x86/kernel/signal.c b/arch/x86/kernel/signal.c
index bed431a38162..e10f96a7e047 100644
--- a/arch/x86/kernel/signal.c
+++ b/arch/x86/kernel/signal.c
@@ -114,7 +114,7 @@ int restore_sigcontext(struct pt_regs *regs, struct sigcontext __user *sc,
                 regs->orig_ax = -1;             /* disable syscall checks */
 
                 get_user_ex(buf, &sc->fpstate);
-                err |= restore_i387_xstate(buf);
+                err |= restore_xstate_sig(buf, config_enabled(CONFIG_X86_32));
 
                 get_user_ex(*pax, &sc->ax);
         } get_user_catch(err);
@@ -206,7 +206,9 @@ get_sigframe(struct k_sigaction *ka, struct pt_regs *regs, size_t frame_size,
              void __user **fpstate)
 {
         /* Default to using normal stack */
+        unsigned long math_size = 0;
         unsigned long sp = regs->sp;
+        unsigned long buf_fx = 0;
         int onsigstack = on_sig_stack(sp);
 
         /* redzone */
@@ -228,10 +230,8 @@ get_sigframe(struct k_sigaction *ka, struct pt_regs *regs, size_t frame_size,
         }
 
         if (used_math()) {
-                sp -= sig_xstate_size;
-#ifdef CONFIG_X86_64
-                sp = round_down(sp, 64);
-#endif /* CONFIG_X86_64 */
+                sp = alloc_mathframe(sp, config_enabled(CONFIG_X86_32),
+                                     &buf_fx, &math_size);
                 *fpstate = (void __user *)sp;
         }
 
@@ -244,8 +244,9 @@ get_sigframe(struct k_sigaction *ka, struct pt_regs *regs, size_t frame_size,
         if (onsigstack && !likely(on_sig_stack(sp)))
                 return (void __user *)-1L;
 
-        /* save i387 state */
-        if (used_math() && save_i387_xstate(*fpstate) < 0)
+        /* save i387 and extended state */
+        if (used_math() &&
+            save_xstate_sig(*fpstate, (void __user *)buf_fx, math_size) < 0)
                 return (void __user *)-1L;
 
         return (void __user *)sp;
diff --git a/arch/x86/kernel/xsave.c b/arch/x86/kernel/xsave.c
index 7a3d4df9eaf6..0923d27f23df 100644
--- a/arch/x86/kernel/xsave.c
+++ b/arch/x86/kernel/xsave.c
@@ -10,9 +10,7 @@
 #include <linux/compat.h>
 #include <asm/i387.h>
 #include <asm/fpu-internal.h>
-#ifdef CONFIG_IA32_EMULATION
-#include <asm/sigcontext32.h>
-#endif
+#include <asm/sigframe.h>
 #include <asm/xcr.h>
 
 /*
@@ -25,11 +23,7 @@ u64 pcntxt_mask;
  */
 static struct xsave_struct *init_xstate_buf;
 
-struct _fpx_sw_bytes fx_sw_reserved;
-#ifdef CONFIG_IA32_EMULATION
-struct _fpx_sw_bytes fx_sw_reserved_ia32;
-#endif
-
+static struct _fpx_sw_bytes fx_sw_reserved, fx_sw_reserved_ia32;
 static unsigned int *xstate_offsets, *xstate_sizes, xstate_features;
 
 /*
@@ -44,9 +38,9 @@ static unsigned int *xstate_offsets, *xstate_sizes, xstate_features;
  */
 void __sanitize_i387_state(struct task_struct *tsk)
 {
-        u64 xstate_bv;
-        int feature_bit = 0x2;
         struct i387_fxsave_struct *fx = &tsk->thread.fpu.state->fxsave;
+        int feature_bit = 0x2;
+        u64 xstate_bv;
 
         if (!fx)
                 return;
@@ -104,215 +98,314 @@ void __sanitize_i387_state(struct task_struct *tsk)
  * Check for the presence of extended state information in the
  * user fpstate pointer in the sigcontext.
  */
-int check_for_xstate(struct i387_fxsave_struct __user *buf,
-                     void __user *fpstate,
-                     struct _fpx_sw_bytes *fx_sw_user)
+static inline int check_for_xstate(struct i387_fxsave_struct __user *buf,
+                                   void __user *fpstate,
+                                   struct _fpx_sw_bytes *fx_sw)
 {
         int min_xstate_size = sizeof(struct i387_fxsave_struct) +
                               sizeof(struct xsave_hdr_struct);
         unsigned int magic2;
-        int err;
 
-        err = __copy_from_user(fx_sw_user, &buf->sw_reserved[0],
-                               sizeof(struct _fpx_sw_bytes));
-        if (err)
-                return -EFAULT;
+        if (__copy_from_user(fx_sw, &buf->sw_reserved[0], sizeof(*fx_sw)))
+                return -1;
 
-        /*
-         * First Magic check failed.
-         */
-        if (fx_sw_user->magic1 != FP_XSTATE_MAGIC1)
-                return -EINVAL;
+        /* Check for the first magic field and other error scenarios. */
+        if (fx_sw->magic1 != FP_XSTATE_MAGIC1 ||
+            fx_sw->xstate_size < min_xstate_size ||
+            fx_sw->xstate_size > xstate_size ||
+            fx_sw->xstate_size > fx_sw->extended_size)
+                return -1;
 
         /*
-         * Check for error scenarios.
-         */
-        if (fx_sw_user->xstate_size < min_xstate_size ||
-            fx_sw_user->xstate_size > xstate_size ||
-            fx_sw_user->xstate_size > fx_sw_user->extended_size)
-                return -EINVAL;
-
-        err = __get_user(magic2, (__u32 __user *) (fpstate +
-                                                   fx_sw_user->extended_size -
-                                                   FP_XSTATE_MAGIC2_SIZE));
-        if (err)
-                return err;
-        /*
          * Check for the presence of second magic word at the end of memory
          * layout. This detects the case where the user just copied the legacy
          * fpstate layout with out copying the extended state information
          * in the memory layout.
          */
-        if (magic2 != FP_XSTATE_MAGIC2)
-                return -EFAULT;
+        if (__get_user(magic2, (__u32 __user *)(fpstate + fx_sw->xstate_size))
+            || magic2 != FP_XSTATE_MAGIC2)
+                return -1;
 
         return 0;
 }
 
-#ifdef CONFIG_X86_64
 /*
  * Signal frame handlers.
  */
+static inline int save_fsave_header(struct task_struct *tsk, void __user *buf)
+{
+        if (use_fxsr()) {
+                struct xsave_struct *xsave = &tsk->thread.fpu.state->xsave;
+                struct user_i387_ia32_struct env;
+                struct _fpstate_ia32 __user *fp = buf;
 
-int save_i387_xstate(void __user *buf)
+                convert_from_fxsr(&env, tsk);
+
+                if (__copy_to_user(buf, &env, sizeof(env)) ||
+                    __put_user(xsave->i387.swd, &fp->status) ||
+                    __put_user(X86_FXSR_MAGIC, &fp->magic))
+                        return -1;
+        } else {
+                struct i387_fsave_struct __user *fp = buf;
+                u32 swd;
+                if (__get_user(swd, &fp->swd) || __put_user(swd, &fp->status))
+                        return -1;
+        }
+
+        return 0;
+}
+
+static inline int save_xstate_epilog(void __user *buf, int ia32_frame)
 {
-        struct task_struct *tsk = current;
-        int err = 0;
+        struct xsave_struct __user *x = buf;
+        struct _fpx_sw_bytes *sw_bytes;
+        u32 xstate_bv;
+        int err;
 
-        if (!access_ok(VERIFY_WRITE, buf, sig_xstate_size))
-                return -EACCES;
+        /* Setup the bytes not touched by the [f]xsave and reserved for SW. */
+        sw_bytes = ia32_frame ? &fx_sw_reserved_ia32 : &fx_sw_reserved;
+        err = __copy_to_user(&x->i387.sw_reserved, sw_bytes, sizeof(*sw_bytes));
 
-        BUG_ON(sig_xstate_size < xstate_size);
+        if (!use_xsave())
+                return err;
 
-        if ((unsigned long)buf % 64)
-                pr_err("%s: bad fpstate %p\n", __func__, buf);
+        err |= __put_user(FP_XSTATE_MAGIC2, (__u32 *)(buf + xstate_size));
 
-        if (!used_math())
-                return 0;
+        /*
+         * Read the xstate_bv which we copied (directly from the cpu or
+         * from the state in task struct) to the user buffers.
+         */
+        err |= __get_user(xstate_bv, (__u32 *)&x->xsave_hdr.xstate_bv);
 
-        if (user_has_fpu()) {
-                if (use_xsave())
-                        err = xsave_user(buf);
-                else
-                        err = fxsave_user(buf);
+        /*
+         * For legacy compatible, we always set FP/SSE bits in the bit
+         * vector while saving the state to the user context. This will
+         * enable us capturing any changes(during sigreturn) to
+         * the FP/SSE bits by the legacy applications which don't touch
+         * xstate_bv in the xsave header.
+         *
+         * xsave aware apps can change the xstate_bv in the xsave
+         * header as well as change any contents in the memory layout.
+         * xrestore as part of sigreturn will capture all the changes.
+         */
+        xstate_bv |= XSTATE_FPSSE;
 
-                if (unlikely(err)) {
-                        __clear_user(buf, xstate_size);
-                        return err;
-                }
+        err |= __put_user(xstate_bv, (__u32 *)&x->xsave_hdr.xstate_bv);
+
+        return err;
+}
+
+static inline int save_user_xstate(struct xsave_struct __user *buf)
+{
+        int err;
+
+        if (use_xsave())
+                err = xsave_user(buf);
+        else if (use_fxsr())
+                err = fxsave_user((struct i387_fxsave_struct __user *) buf);
+        else
+                err = fsave_user((struct i387_fsave_struct __user *) buf);
+
+        if (unlikely(err) && __clear_user(buf, xstate_size))
+                err = -EFAULT;
+        return err;
+}
+
+/*
+ * Save the fpu, extended register state to the user signal frame.
+ *
+ * 'buf_fx' is the 64-byte aligned pointer at which the [f|fx|x]save
+ *  state is copied.
+ *  'buf' points to the 'buf_fx' or to the fsave header followed by 'buf_fx'.
+ *
+ *      buf == buf_fx for 64-bit frames and 32-bit fsave frame.
+ *      buf != buf_fx for 32-bit frames with fxstate.
+ *
+ * If the fpu, extended register state is live, save the state directly
+ * to the user frame pointed by the aligned pointer 'buf_fx'. Otherwise,
+ * copy the thread's fpu state to the user frame starting at 'buf_fx'.
+ *
+ * If this is a 32-bit frame with fxstate, put a fsave header before
+ * the aligned state at 'buf_fx'.
+ *
+ * For [f]xsave state, update the SW reserved fields in the [f]xsave frame
+ * indicating the absence/presence of the extended state to the user.
+ */
+int save_xstate_sig(void __user *buf, void __user *buf_fx, int size)
+{
+        struct xsave_struct *xsave = &current->thread.fpu.state->xsave;
+        struct task_struct *tsk = current;
+        int ia32_fxstate = (buf != buf_fx);
+
+        ia32_fxstate &= (config_enabled(CONFIG_X86_32) ||
+                         config_enabled(CONFIG_IA32_EMULATION));
+
+        if (!access_ok(VERIFY_WRITE, buf, size))
+                return -EACCES;
+
+        if (!HAVE_HWFP)
+                return fpregs_soft_get(current, NULL, 0,
+                        sizeof(struct user_i387_ia32_struct), NULL,
+                        (struct _fpstate_ia32 __user *) buf) ? -1 : 1;
+
+        if (user_has_fpu()) {
+                /* Save the live register state to the user directly. */
+                if (save_user_xstate(buf_fx))
+                        return -1;
+                /* Update the thread's fxstate to save the fsave header. */
+                if (ia32_fxstate)
+                        fpu_fxsave(&tsk->thread.fpu);
                 user_fpu_end();
         } else {
                 sanitize_i387_state(tsk);
-                if (__copy_to_user(buf, &tsk->thread.fpu.state->fxsave,
-                                   xstate_size))
+                if (__copy_to_user(buf_fx, xsave, xstate_size))
                         return -1;
         }
 
-        clear_used_math(); /* trigger finit */
+        /* Save the fsave header for the 32-bit frames. */
+        if ((ia32_fxstate || !use_fxsr()) && save_fsave_header(tsk, buf))
+                return -1;
 
-        if (use_xsave()) {
-                struct _fpstate __user *fx = buf;
-                struct _xstate __user *x = buf;
-                u64 xstate_bv;
+        if (use_fxsr() && save_xstate_epilog(buf_fx, ia32_fxstate))
+                return -1;
+
+        drop_fpu(tsk);  /* trigger finit */
+
+        return 0;
+}
 
-                err = __copy_to_user(&fx->sw_reserved, &fx_sw_reserved,
-                                     sizeof(struct _fpx_sw_bytes));
+static inline void
+sanitize_restored_xstate(struct task_struct *tsk,
+                         struct user_i387_ia32_struct *ia32_env,
+                         u64 xstate_bv, int fx_only)
+{
+        struct xsave_struct *xsave = &tsk->thread.fpu.state->xsave;
+        struct xsave_hdr_struct *xsave_hdr = &xsave->xsave_hdr;
 
-                err |= __put_user(FP_XSTATE_MAGIC2,
-                                  (__u32 __user *) (buf + sig_xstate_size
-                                                    - FP_XSTATE_MAGIC2_SIZE));
+        if (use_xsave()) {
+                /* These bits must be zero. */
+                xsave_hdr->reserved1[0] = xsave_hdr->reserved1[1] = 0;
 
                 /*
-                 * Read the xstate_bv which we copied (directly from the cpu or
-                 * from the state in task struct) to the user buffers and
-                 * set the FP/SSE bits.
+                 * Init the state that is not present in the memory
+                 * layout and not enabled by the OS.
                  */
-                err |= __get_user(xstate_bv, &x->xstate_hdr.xstate_bv);
+                if (fx_only)
+                        xsave_hdr->xstate_bv = XSTATE_FPSSE;
+                else
+                        xsave_hdr->xstate_bv &= (pcntxt_mask & xstate_bv);
+        }
 
+        if (use_fxsr()) {
                 /*
-                 * For legacy compatible, we always set FP/SSE bits in the bit
-                 * vector while saving the state to the user context. This will
-                 * enable us capturing any changes(during sigreturn) to
-                 * the FP/SSE bits by the legacy applications which don't touch
-                 * xstate_bv in the xsave header.
-                 *
-                 * xsave aware apps can change the xstate_bv in the xsave
-                 * header as well as change any contents in the memory layout.
-                 * xrestore as part of sigreturn will capture all the changes.
+                 * mscsr reserved bits must be masked to zero for security
+                 * reasons.
                  */
-                xstate_bv |= XSTATE_FPSSE;
-
-                err |= __put_user(xstate_bv, &x->xstate_hdr.xstate_bv);
+                xsave->i387.mxcsr &= mxcsr_feature_mask;
 
-                if (err)
-                        return err;
+                convert_to_fxsr(tsk, ia32_env);
         }
-
-        return 1;
 }
 
 /*
- * Restore the extended state if present. Otherwise, restore the FP/SSE
- * state.
+ * Restore the extended state if present. Otherwise, restore the FP/SSE state.
  */
-static int restore_user_xstate(void __user *buf)
+static inline int restore_user_xstate(void __user *buf, u64 xbv, int fx_only)
 {
-        struct _fpx_sw_bytes fx_sw_user;
-        u64 mask;
-        int err;
-
-        if (((unsigned long)buf % 64) ||
-             check_for_xstate(buf, buf, &fx_sw_user))
-                goto fx_only;
-
-        mask = fx_sw_user.xstate_bv;
-
-        /*
-         * restore the state passed by the user.
-         */
-        err = xrestore_user(buf, mask);
-        if (err)
-                return err;
-
-        /*
-         * init the state skipped by the user.
-         */
-        mask = pcntxt_mask & ~mask;
-        if (unlikely(mask))
-                xrstor_state(init_xstate_buf, mask);
-
-        return 0;
-
-fx_only:
-        /*
-         * couldn't find the extended state information in the
-         * memory layout. Restore just the FP/SSE and init all
-         * the other extended state.
-         */
-        xrstor_state(init_xstate_buf, pcntxt_mask & ~XSTATE_FPSSE);
-        return fxrstor_checking((__force struct i387_fxsave_struct *)buf);
+        if (use_xsave()) {
+                if ((unsigned long)buf % 64 || fx_only) {
+                        u64 init_bv = pcntxt_mask & ~XSTATE_FPSSE;
+                        xrstor_state(init_xstate_buf, init_bv);
+                        return fxrstor_checking((__force void *) buf);
+                } else {
+                        u64 init_bv = pcntxt_mask & ~xbv;
+                        if (unlikely(init_bv))
+                                xrstor_state(init_xstate_buf, init_bv);
+                        return xrestore_user(buf, xbv);
+                }
+        } else if (use_fxsr()) {
+                return fxrstor_checking((__force void *) buf);
+        } else
+                return frstor_checking((__force void *) buf);
 }
 
-/*
- * This restores directly out of user space. Exceptions are handled.
- */
-int restore_i387_xstate(void __user *buf)
+int __restore_xstate_sig(void __user *buf, void __user *buf_fx, int size)
 {
+        int ia32_fxstate = (buf != buf_fx);
         struct task_struct *tsk = current;
-        int err = 0;
+        int state_size = xstate_size;
+        u64 xstate_bv = 0;
+        int fx_only = 0;
+
+        ia32_fxstate &= (config_enabled(CONFIG_X86_32) ||
+                         config_enabled(CONFIG_IA32_EMULATION));
 
         if (!buf) {
-                if (used_math())
-                        goto clear;
+                drop_fpu(tsk);
                 return 0;
-        } else
-                if (!access_ok(VERIFY_READ, buf, sig_xstate_size))
-                        return -EACCES;
+        }
+
+        if (!access_ok(VERIFY_READ, buf, size))
+                return -EACCES;
+
+        if (!used_math() && init_fpu(tsk))
+                return -1;
 
-        if (!used_math()) {
-                err = init_fpu(tsk);
-                if (err)
-                        return err;
+        if (!HAVE_HWFP) {
+                return fpregs_soft_set(current, NULL,
+                                       0, sizeof(struct user_i387_ia32_struct),
+                                       NULL, buf) != 0;
         }
 
-        user_fpu_begin();
-        if (use_xsave())
-                err = restore_user_xstate(buf);
-        else
-                err = fxrstor_checking((__force struct i387_fxsave_struct *)
-                                       buf);
-        if (unlikely(err)) {
+        if (use_xsave()) {
+                struct _fpx_sw_bytes fx_sw_user;
+                if (unlikely(check_for_xstate(buf_fx, buf_fx, &fx_sw_user))) {
+                        /*
+                         * Couldn't find the extended state information in the
+                         * memory layout. Restore just the FP/SSE and init all
+                         * the other extended state.
+                         */
+                        state_size = sizeof(struct i387_fxsave_struct);
+                        fx_only = 1;
+                } else {
+                        state_size = fx_sw_user.xstate_size;
+                        xstate_bv = fx_sw_user.xstate_bv;
+                }
+        }
+
+        if (ia32_fxstate) {
+                /*
+                 * For 32-bit frames with fxstate, copy the user state to the
+                 * thread's fpu state, reconstruct fxstate from the fsave
+                 * header. Sanitize the copied state etc.
+                 */
+                struct xsave_struct *xsave = &tsk->thread.fpu.state->xsave;
+                struct user_i387_ia32_struct env;
+
+                stop_fpu_preload(tsk);
+                unlazy_fpu(tsk);
+
+                if (__copy_from_user(xsave, buf_fx, state_size) ||
+                    __copy_from_user(&env, buf, sizeof(env))) {
+                        drop_fpu(tsk);
+                        return -1;
+                }
+
+                sanitize_restored_xstate(tsk, &env, xstate_bv, fx_only);
+        } else {
                 /*
-                 * Encountered an error while doing the restore from the
-                 * user buffer, clear the fpu state.
+                 * For 64-bit frames and 32-bit fsave frames, restore the user
+                 * state to the registers directly (with exceptions handled).
                  */
-clear:
-                clear_fpu(tsk);
-                clear_used_math();
+                user_fpu_begin();
+                if (restore_user_xstate(buf_fx, xstate_bv, fx_only)) {
+                        drop_fpu(tsk);
+                        return -1;
+                }
         }
-        return err;
+
+        return 0;
 }
-#endif
 
 /*
  * Prepare the SW reserved portion of the fxsave memory layout, indicating
@@ -323,31 +416,22 @@ clear:
  */
 static void prepare_fx_sw_frame(void)
 {
-        int size_extended = (xstate_size - sizeof(struct i387_fxsave_struct)) +
-                             FP_XSTATE_MAGIC2_SIZE;
-
-        sig_xstate_size = sizeof(struct _fpstate) + size_extended;
-
-#ifdef CONFIG_IA32_EMULATION
-        sig_xstate_ia32_size = sizeof(struct _fpstate_ia32) + size_extended;
-#endif
+        int fsave_header_size = sizeof(struct i387_fsave_struct);
+        int size = xstate_size + FP_XSTATE_MAGIC2_SIZE;
 
-        memset(&fx_sw_reserved, 0, sizeof(fx_sw_reserved));
+        if (config_enabled(CONFIG_X86_32))
+                size += fsave_header_size;
 
         fx_sw_reserved.magic1 = FP_XSTATE_MAGIC1;
-        fx_sw_reserved.extended_size = sig_xstate_size;
+        fx_sw_reserved.extended_size = size;
         fx_sw_reserved.xstate_bv = pcntxt_mask;
         fx_sw_reserved.xstate_size = xstate_size;
-#ifdef CONFIG_IA32_EMULATION
-        memcpy(&fx_sw_reserved_ia32, &fx_sw_reserved,
-               sizeof(struct _fpx_sw_bytes));
-        fx_sw_reserved_ia32.extended_size = sig_xstate_ia32_size;
-#endif
-}
 
-#ifdef CONFIG_X86_64
-unsigned int sig_xstate_size = sizeof(struct _fpstate);
-#endif
+        if (config_enabled(CONFIG_IA32_EMULATION)) {
+                fx_sw_reserved_ia32 = fx_sw_reserved;
+                fx_sw_reserved_ia32.extended_size += fsave_header_size;
+        }
+}
 
 /*
  * Enable the extended processor state save/restore feature