diff options
Diffstat (limited to 'arch/arm/kernel/signal.c')
-rw-r--r-- | arch/arm/kernel/signal.c | 121 |
1 files changed, 30 insertions, 91 deletions
diff --git a/arch/arm/kernel/signal.c b/arch/arm/kernel/signal.c index a94d75fef59..765922bcf9e 100644 --- a/arch/arm/kernel/signal.c +++ b/arch/arm/kernel/signal.c @@ -139,93 +139,33 @@ struct iwmmxt_sigframe { unsigned long storage[0x98/4]; }; -static int page_present(struct mm_struct *mm, void __user *uptr, int wr) -{ - unsigned long addr = (unsigned long)uptr; - pgd_t *pgd = pgd_offset(mm, addr); - if (pgd_present(*pgd)) { - pmd_t *pmd = pmd_offset(pgd, addr); - if (pmd_present(*pmd)) { - pte_t *pte = pte_offset_map(pmd, addr); - return (pte_present(*pte) && (!wr || pte_write(*pte))); - } - } - return 0; -} - -static int copy_locked(void __user *uptr, void *kptr, size_t size, int write, - void (*copyfn)(void *, void __user *)) -{ - unsigned char v, __user *userptr = uptr; - int err = 0; - - do { - struct mm_struct *mm; - - if (write) { - __put_user_error(0, userptr, err); - __put_user_error(0, userptr + size - 1, err); - } else { - __get_user_error(v, userptr, err); - __get_user_error(v, userptr + size - 1, err); - } - - if (err) - break; - - mm = current->mm; - spin_lock(&mm->page_table_lock); - if (page_present(mm, userptr, write) && - page_present(mm, userptr + size - 1, write)) { - copyfn(kptr, uptr); - } else - err = 1; - spin_unlock(&mm->page_table_lock); - } while (err); - - return err; -} - static int preserve_iwmmxt_context(struct iwmmxt_sigframe *frame) { - int err = 0; + char kbuf[sizeof(*frame) + 8]; + struct iwmmxt_sigframe *kframe; /* the iWMMXt context must be 64 bit aligned */ - WARN_ON((unsigned long)frame & 7); - - __put_user_error(IWMMXT_MAGIC0, &frame->magic0, err); - __put_user_error(IWMMXT_MAGIC1, &frame->magic1, err); - - /* - * iwmmxt_task_copy() doesn't check user permissions. - * Let's do a dummy write on the upper boundary to ensure - * access to user mem is OK all way up. - */ - err |= copy_locked(&frame->storage, current_thread_info(), - sizeof(frame->storage), 1, iwmmxt_task_copy); - return err; + kframe = (struct iwmmxt_sigframe *)((unsigned long)(kbuf + 8) & ~7); + kframe->magic0 = IWMMXT_MAGIC0; + kframe->magic1 = IWMMXT_MAGIC1; + iwmmxt_task_copy(current_thread_info(), &kframe->storage); + return __copy_to_user(frame, kframe, sizeof(*frame)); } static int restore_iwmmxt_context(struct iwmmxt_sigframe *frame) { - unsigned long magic0, magic1; - int err = 0; - - /* the iWMMXt context is 64 bit aligned */ - WARN_ON((unsigned long)frame & 7); + char kbuf[sizeof(*frame) + 8]; + struct iwmmxt_sigframe *kframe; - /* - * Validate iWMMXt context signature. - * Also, iwmmxt_task_restore() doesn't check user permissions. - * Let's do a dummy write on the upper boundary to ensure - * access to user mem is OK all way up. - */ - __get_user_error(magic0, &frame->magic0, err); - __get_user_error(magic1, &frame->magic1, err); - if (!err && magic0 == IWMMXT_MAGIC0 && magic1 == IWMMXT_MAGIC1) - err = copy_locked(&frame->storage, current_thread_info(), - sizeof(frame->storage), 0, iwmmxt_task_restore); - return err; + /* the iWMMXt context must be 64 bit aligned */ + kframe = (struct iwmmxt_sigframe *)((unsigned long)(kbuf + 8) & ~7); + if (__copy_from_user(kframe, frame, sizeof(*frame))) + return -1; + if (kframe->magic0 != IWMMXT_MAGIC0 || + kframe->magic1 != IWMMXT_MAGIC1) + return -1; + iwmmxt_task_restore(current_thread_info(), &kframe->storage); + return 0; } #endif @@ -655,23 +595,22 @@ handle_signal(unsigned long sig, struct k_sigaction *ka, */ ret |= !valid_user_regs(regs); - /* - * Block the signal if we were unsuccessful. - */ if (ret != 0) { - spin_lock_irq(&tsk->sighand->siglock); - sigorsets(&tsk->blocked, &tsk->blocked, - &ka->sa.sa_mask); - if (!(ka->sa.sa_flags & SA_NODEFER)) - sigaddset(&tsk->blocked, sig); - recalc_sigpending(); - spin_unlock_irq(&tsk->sighand->siglock); + force_sigsegv(sig, tsk); + return; } - if (ret == 0) - return; + /* + * Block the signal if we were successful. + */ + spin_lock_irq(&tsk->sighand->siglock); + sigorsets(&tsk->blocked, &tsk->blocked, + &ka->sa.sa_mask); + if (!(ka->sa.sa_flags & SA_NODEFER)) + sigaddset(&tsk->blocked, sig); + recalc_sigpending(); + spin_unlock_irq(&tsk->sighand->siglock); - force_sigsegv(sig, tsk); } /* |