/*
* FPU register's regset abstraction, for ptrace, core dumps, etc.
*/
+#include <linux/sched/task_stack.h>
+#include <linux/vmalloc.h>
+
#include <asm/fpu/internal.h>
#include <asm/fpu/signal.h>
#include <asm/fpu/regset.h>
#include <asm/fpu/xstate.h>
-#include <linux/sched/task_stack.h>
/*
* The xstateregs_active() routine is the same as the regset_fpregs_active() routine,
const void *kbuf, const void __user *ubuf)
{
struct fpu *fpu = &target->thread.fpu;
- struct xregs_state *xsave;
+ struct xregs_state *tmpbuf = NULL;
int ret;
- if (!boot_cpu_has(X86_FEATURE_XSAVE))
+ if (!cpu_feature_enabled(X86_FEATURE_XSAVE))
return -ENODEV;
/*
if (pos != 0 || count != fpu_user_xstate_size)
return -EFAULT;
- xsave = &fpu->state.xsave;
-
- fpu__prepare_write(fpu);
+ if (!kbuf) {
+ tmpbuf = vmalloc(count);
+ if (!tmpbuf)
+ return -ENOMEM;
- if (using_compacted_format()) {
- if (kbuf)
- ret = copy_kernel_to_xstate(xsave, kbuf);
- else
- ret = copy_user_to_xstate(xsave, ubuf);
- } else {
- ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, xsave, 0, -1);
- if (!ret)
- ret = validate_user_xstate_header(&xsave->header);
+ if (copy_from_user(tmpbuf, ubuf, count)) {
+ ret = -EFAULT;
+ goto out;
+ }
}
- /*
- * mxcsr reserved bits must be masked to zero for security reasons.
- */
- xsave->i387.mxcsr &= mxcsr_feature_mask;
-
- /*
- * In case of failure, mark all states as init:
- */
- if (ret)
- fpstate_init(&fpu->state);
+ fpu__prepare_write(fpu);
+ ret = copy_kernel_to_xstate(&fpu->state.xsave, kbuf ?: tmpbuf);
+out:
+ vfree(tmpbuf);
return ret;
}
}
/* Validate an xstate header supplied by userspace (ptrace or sigreturn) */
-int validate_user_xstate_header(const struct xstate_header *hdr)
+static int validate_user_xstate_header(const struct xstate_header *hdr)
{
/* No unknown or supervisor features may be set */
if (hdr->xfeatures & ~xfeatures_mask_user())
}
/*
- * Convert from a ptrace standard-format kernel buffer to kernel XSAVES format
+ * Convert from a ptrace standard-format kernel buffer to kernel XSAVE[S] format
* and copy to the target thread. This is called from xstateregs_set().
*/
int copy_kernel_to_xstate(struct xregs_state *xsave, const void *kbuf)
*/
xsave->header.xfeatures |= hdr.xfeatures;
+ /* mxcsr reserved bits must be masked to zero for historical reasons. */
+ xsave->i387.mxcsr &= mxcsr_feature_mask;
+
return 0;
}
/*
- * Convert from a ptrace or sigreturn standard-format user-space buffer to
- * kernel XSAVES format and copy to the target thread. This is called from
- * xstateregs_set(), as well as potentially from the sigreturn() and
- * rt_sigreturn() system calls.
+ * Convert from a sigreturn standard-format user-space buffer to kernel
+ * XSAVE[S] format and copy to the target thread. This is called from the
+ * sigreturn() and rt_sigreturn() system calls.
*/
int copy_user_to_xstate(struct xregs_state *xsave, const void __user *ubuf)
{