diff options
Diffstat (limited to 'arch/x86/kernel/fpu/signal.c')
| -rw-r--r-- | arch/x86/kernel/fpu/signal.c | 40 |
1 files changed, 15 insertions, 25 deletions
diff --git a/arch/x86/kernel/fpu/signal.c b/arch/x86/kernel/fpu/signal.c index 55b80de13ea5..7296a9bb78e7 100644 --- a/arch/x86/kernel/fpu/signal.c +++ b/arch/x86/kernel/fpu/signal.c @@ -207,11 +207,11 @@ int copy_fpstate_to_sigframe(void __user *buf, void __user *buf_fx, int size) } static inline void -sanitize_restored_xstate(struct task_struct *tsk, +sanitize_restored_xstate(union fpregs_state *state, struct user_i387_ia32_struct *ia32_env, u64 xfeatures, int fx_only) { - struct xregs_state *xsave = &tsk->thread.fpu.state.xsave; + struct xregs_state *xsave = &state->xsave; struct xstate_header *header = &xsave->header; if (use_xsave()) { @@ -238,7 +238,7 @@ sanitize_restored_xstate(struct task_struct *tsk, */ xsave->i387.mxcsr &= mxcsr_feature_mask; - convert_to_fxsr(tsk, ia32_env); + convert_to_fxsr(&state->fxsave, ia32_env); } } @@ -284,8 +284,6 @@ static int __fpu__restore_sig(void __user *buf, void __user *buf_fx, int size) if (!access_ok(buf, size)) return -EACCES; - fpu__initialize(fpu); - if (!static_cpu_has(X86_FEATURE_FPU)) return fpregs_soft_set(current, NULL, 0, sizeof(struct user_i387_ia32_struct), @@ -315,40 +313,32 @@ static int __fpu__restore_sig(void __user *buf, void __user *buf_fx, int size) * header. Validate and sanitize the copied state. */ struct user_i387_ia32_struct env; + union fpregs_state *state; int err = 0; + void *tmp; - /* - * Drop the current fpu which clears fpu->initialized. This ensures - * that any context-switch during the copy of the new state, - * avoids the intermediate state from getting restored/saved. - * Thus avoiding the new restored state from getting corrupted. - * We will be ready to restore/save the state only after - * fpu->initialized is again set. - */ - fpu__drop(fpu); + tmp = kzalloc(sizeof(*state) + fpu_kernel_xstate_size + 64, GFP_KERNEL); + if (!tmp) + return -ENOMEM; + state = PTR_ALIGN(tmp, 64); if (using_compacted_format()) { - err = copy_user_to_xstate(&fpu->state.xsave, buf_fx); + err = copy_user_to_xstate(&state->xsave, buf_fx); } else { - err = __copy_from_user(&fpu->state.xsave, buf_fx, state_size); + err = __copy_from_user(&state->xsave, buf_fx, state_size); if (!err && state_size > offsetof(struct xregs_state, header)) - err = validate_xstate_header(&fpu->state.xsave.header); + err = validate_xstate_header(&state->xsave.header); } if (err || __copy_from_user(&env, buf, sizeof(env))) { - fpstate_init(&fpu->state); - trace_x86_fpu_init_state(fpu); err = -1; } else { - sanitize_restored_xstate(tsk, &env, xfeatures, fx_only); + sanitize_restored_xstate(state, &env, xfeatures, fx_only); + copy_kernel_to_fpregs(state); } - local_bh_disable(); - fpu->initialized = 1; - fpu__restore(fpu); - local_bh_enable(); - + kfree(tmp); return err; } else { /* |