#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;
*/
#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
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))
: [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
/*
* 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 */
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();
}
/*
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
#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?
*
}
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)
* 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;
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;
return ret;
}
-/*
- * 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 =
- ¤t->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.
#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>
/*
*/
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;
/*
*/
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;
* 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 = ¤t->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
*/
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
projects / users / hch / configfs.git / commitdiff