From: Martijn Coenen Date: Fri, 3 Feb 2017 22:40:49 +0000 (-0800) Subject: binder: Refactor binder_transact() X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=a056af42032e56f6ee8e07cd22f1ea2b2e07f51b;p=GitHub%2Fmoto-9609%2Fandroid_kernel_motorola_exynos9610.git binder: Refactor binder_transact() Moved handling of fixup for binder objects, handles and file descriptors into separate functions. Cc: Greg Kroah-Hartman Cc: Martijn Coenen Cc: Arve Hjønnevåg Cc: Amit Pundir Cc: Serban Constantinescu Cc: Dmitry Shmidt Cc: Rom Lemarchand Cc: Android Kernel Team Signed-off-by: Martijn Coenen Signed-off-by: John Stultz Signed-off-by: Greg Kroah-Hartman --- diff --git a/drivers/android/binder.c b/drivers/android/binder.c index 705caf55005e..1a6969cdae7f 100644 --- a/drivers/android/binder.c +++ b/drivers/android/binder.c @@ -1390,10 +1390,172 @@ static void binder_transaction_buffer_release(struct binder_proc *proc, } } +static int binder_translate_binder(struct flat_binder_object *fp, + struct binder_transaction *t, + struct binder_thread *thread) +{ + struct binder_node *node; + struct binder_ref *ref; + struct binder_proc *proc = thread->proc; + struct binder_proc *target_proc = t->to_proc; + + node = binder_get_node(proc, fp->binder); + if (!node) { + node = binder_new_node(proc, fp->binder, fp->cookie); + if (!node) + return -ENOMEM; + + node->min_priority = fp->flags & FLAT_BINDER_FLAG_PRIORITY_MASK; + node->accept_fds = !!(fp->flags & FLAT_BINDER_FLAG_ACCEPTS_FDS); + } + if (fp->cookie != node->cookie) { + binder_user_error("%d:%d sending u%016llx node %d, cookie mismatch %016llx != %016llx\n", + proc->pid, thread->pid, (u64)fp->binder, + node->debug_id, (u64)fp->cookie, + (u64)node->cookie); + return -EINVAL; + } + if (security_binder_transfer_binder(proc->tsk, target_proc->tsk)) + return -EPERM; + + ref = binder_get_ref_for_node(target_proc, node); + if (!ref) + return -EINVAL; + + if (fp->hdr.type == BINDER_TYPE_BINDER) + fp->hdr.type = BINDER_TYPE_HANDLE; + else + fp->hdr.type = BINDER_TYPE_WEAK_HANDLE; + fp->binder = 0; + fp->handle = ref->desc; + fp->cookie = 0; + binder_inc_ref(ref, fp->hdr.type == BINDER_TYPE_HANDLE, &thread->todo); + + trace_binder_transaction_node_to_ref(t, node, ref); + binder_debug(BINDER_DEBUG_TRANSACTION, + " node %d u%016llx -> ref %d desc %d\n", + node->debug_id, (u64)node->ptr, + ref->debug_id, ref->desc); + + return 0; +} + +static int binder_translate_handle(struct flat_binder_object *fp, + struct binder_transaction *t, + struct binder_thread *thread) +{ + struct binder_ref *ref; + struct binder_proc *proc = thread->proc; + struct binder_proc *target_proc = t->to_proc; + + ref = binder_get_ref(proc, fp->handle, + fp->hdr.type == BINDER_TYPE_HANDLE); + if (!ref) { + binder_user_error("%d:%d got transaction with invalid handle, %d\n", + proc->pid, thread->pid, fp->handle); + return -EINVAL; + } + if (security_binder_transfer_binder(proc->tsk, target_proc->tsk)) + return -EPERM; + + if (ref->node->proc == target_proc) { + if (fp->hdr.type == BINDER_TYPE_HANDLE) + fp->hdr.type = BINDER_TYPE_BINDER; + else + fp->hdr.type = BINDER_TYPE_WEAK_BINDER; + fp->binder = ref->node->ptr; + fp->cookie = ref->node->cookie; + binder_inc_node(ref->node, fp->hdr.type == BINDER_TYPE_BINDER, + 0, NULL); + trace_binder_transaction_ref_to_node(t, ref); + binder_debug(BINDER_DEBUG_TRANSACTION, + " ref %d desc %d -> node %d u%016llx\n", + ref->debug_id, ref->desc, ref->node->debug_id, + (u64)ref->node->ptr); + } else { + struct binder_ref *new_ref; + + new_ref = binder_get_ref_for_node(target_proc, ref->node); + if (!new_ref) + return -EINVAL; + + fp->binder = 0; + fp->handle = new_ref->desc; + fp->cookie = 0; + binder_inc_ref(new_ref, fp->hdr.type == BINDER_TYPE_HANDLE, + NULL); + trace_binder_transaction_ref_to_ref(t, ref, new_ref); + binder_debug(BINDER_DEBUG_TRANSACTION, + " ref %d desc %d -> ref %d desc %d (node %d)\n", + ref->debug_id, ref->desc, new_ref->debug_id, + new_ref->desc, ref->node->debug_id); + } + return 0; +} + +static int binder_translate_fd(int fd, + struct binder_transaction *t, + struct binder_thread *thread, + struct binder_transaction *in_reply_to) +{ + struct binder_proc *proc = thread->proc; + struct binder_proc *target_proc = t->to_proc; + int target_fd; + struct file *file; + int ret; + bool target_allows_fd; + + if (in_reply_to) + target_allows_fd = !!(in_reply_to->flags & TF_ACCEPT_FDS); + else + target_allows_fd = t->buffer->target_node->accept_fds; + if (!target_allows_fd) { + binder_user_error("%d:%d got %s with fd, %d, but target does not allow fds\n", + proc->pid, thread->pid, + in_reply_to ? "reply" : "transaction", + fd); + ret = -EPERM; + goto err_fd_not_accepted; + } + + file = fget(fd); + if (!file) { + binder_user_error("%d:%d got transaction with invalid fd, %d\n", + proc->pid, thread->pid, fd); + ret = -EBADF; + goto err_fget; + } + ret = security_binder_transfer_file(proc->tsk, target_proc->tsk, file); + if (ret < 0) { + ret = -EPERM; + goto err_security; + } + + target_fd = task_get_unused_fd_flags(target_proc, O_CLOEXEC); + if (target_fd < 0) { + ret = -ENOMEM; + goto err_get_unused_fd; + } + task_fd_install(target_proc, target_fd, file); + trace_binder_transaction_fd(t, fd, target_fd); + binder_debug(BINDER_DEBUG_TRANSACTION, " fd %d -> %d\n", + fd, target_fd); + + return target_fd; + +err_get_unused_fd: +err_security: + fput(file); +err_fget: +err_fd_not_accepted: + return ret; +} + static void binder_transaction(struct binder_proc *proc, struct binder_thread *thread, struct binder_transaction_data *tr, int reply) { + int ret; struct binder_transaction *t; struct binder_work *tcomplete; binder_size_t *offp, *off_end; @@ -1621,157 +1783,35 @@ static void binder_transaction(struct binder_proc *proc, case BINDER_TYPE_BINDER: case BINDER_TYPE_WEAK_BINDER: { struct flat_binder_object *fp; - struct binder_node *node; - struct binder_ref *ref; fp = to_flat_binder_object(hdr); - node = binder_get_node(proc, fp->binder); - if (node == NULL) { - node = binder_new_node(proc, fp->binder, fp->cookie); - if (node == NULL) { - return_error = BR_FAILED_REPLY; - goto err_binder_new_node_failed; - } - node->min_priority = fp->flags & FLAT_BINDER_FLAG_PRIORITY_MASK; - node->accept_fds = !!(fp->flags & FLAT_BINDER_FLAG_ACCEPTS_FDS); - } - if (fp->cookie != node->cookie) { - binder_user_error("%d:%d sending u%016llx node %d, cookie mismatch %016llx != %016llx\n", - proc->pid, thread->pid, - (u64)fp->binder, node->debug_id, - (u64)fp->cookie, (u64)node->cookie); + ret = binder_translate_binder(fp, t, thread); + if (ret < 0) { return_error = BR_FAILED_REPLY; - goto err_binder_get_ref_for_node_failed; + goto err_translate_failed; } - if (security_binder_transfer_binder(proc->tsk, - target_proc->tsk)) { - return_error = BR_FAILED_REPLY; - goto err_binder_get_ref_for_node_failed; - } - ref = binder_get_ref_for_node(target_proc, node); - if (ref == NULL) { - return_error = BR_FAILED_REPLY; - goto err_binder_get_ref_for_node_failed; - } - if (hdr->type == BINDER_TYPE_BINDER) - hdr->type = BINDER_TYPE_HANDLE; - else - hdr->type = BINDER_TYPE_WEAK_HANDLE; - fp->binder = 0; - fp->handle = ref->desc; - fp->cookie = 0; - binder_inc_ref(ref, hdr->type == BINDER_TYPE_HANDLE, - &thread->todo); - - trace_binder_transaction_node_to_ref(t, node, ref); - binder_debug(BINDER_DEBUG_TRANSACTION, - " node %d u%016llx -> ref %d desc %d\n", - node->debug_id, (u64)node->ptr, - ref->debug_id, ref->desc); } break; case BINDER_TYPE_HANDLE: case BINDER_TYPE_WEAK_HANDLE: { struct flat_binder_object *fp; - struct binder_ref *ref; fp = to_flat_binder_object(hdr); - ref = binder_get_ref(proc, fp->handle, - hdr->type == BINDER_TYPE_HANDLE); - if (ref == NULL) { - binder_user_error("%d:%d got transaction with invalid handle, %d\n", - proc->pid, - thread->pid, fp->handle); + ret = binder_translate_handle(fp, t, thread); + if (ret < 0) { return_error = BR_FAILED_REPLY; - goto err_binder_get_ref_failed; - } - if (security_binder_transfer_binder(proc->tsk, - target_proc->tsk)) { - return_error = BR_FAILED_REPLY; - goto err_binder_get_ref_failed; - } - if (ref->node->proc == target_proc) { - if (hdr->type == BINDER_TYPE_HANDLE) - hdr->type = BINDER_TYPE_BINDER; - else - hdr->type = BINDER_TYPE_WEAK_BINDER; - fp->binder = ref->node->ptr; - fp->cookie = ref->node->cookie; - binder_inc_node(ref->node, - hdr->type == BINDER_TYPE_BINDER, - 0, NULL); - trace_binder_transaction_ref_to_node(t, ref); - binder_debug(BINDER_DEBUG_TRANSACTION, - " ref %d desc %d -> node %d u%016llx\n", - ref->debug_id, ref->desc, ref->node->debug_id, - (u64)ref->node->ptr); - } else { - struct binder_ref *new_ref; - - new_ref = binder_get_ref_for_node(target_proc, ref->node); - if (new_ref == NULL) { - return_error = BR_FAILED_REPLY; - goto err_binder_get_ref_for_node_failed; - } - fp->binder = 0; - fp->handle = new_ref->desc; - fp->cookie = 0; - binder_inc_ref(new_ref, - hdr->type == BINDER_TYPE_HANDLE, - NULL); - trace_binder_transaction_ref_to_ref(t, ref, - new_ref); - binder_debug(BINDER_DEBUG_TRANSACTION, - " ref %d desc %d -> ref %d desc %d (node %d)\n", - ref->debug_id, ref->desc, new_ref->debug_id, - new_ref->desc, ref->node->debug_id); + goto err_translate_failed; } } break; case BINDER_TYPE_FD: { - int target_fd; - struct file *file; struct binder_fd_object *fp = to_binder_fd_object(hdr); + int target_fd = binder_translate_fd(fp->fd, t, thread, + in_reply_to); - if (reply) { - if (!(in_reply_to->flags & TF_ACCEPT_FDS)) { - binder_user_error("%d:%d got reply with fd, %d, but target does not allow fds\n", - proc->pid, thread->pid, fp->fd); - return_error = BR_FAILED_REPLY; - goto err_fd_not_allowed; - } - } else if (!target_node->accept_fds) { - binder_user_error("%d:%d got transaction with fd, %d, but target does not allow fds\n", - proc->pid, thread->pid, fp->fd); - return_error = BR_FAILED_REPLY; - goto err_fd_not_allowed; - } - - file = fget(fp->fd); - if (file == NULL) { - binder_user_error("%d:%d got transaction with invalid fd, %d\n", - proc->pid, thread->pid, fp->fd); - return_error = BR_FAILED_REPLY; - goto err_fget_failed; - } - if (security_binder_transfer_file(proc->tsk, - target_proc->tsk, - file) < 0) { - fput(file); - return_error = BR_FAILED_REPLY; - goto err_get_unused_fd_failed; - } - target_fd = task_get_unused_fd_flags(target_proc, O_CLOEXEC); if (target_fd < 0) { - fput(file); return_error = BR_FAILED_REPLY; - goto err_get_unused_fd_failed; + goto err_translate_failed; } - task_fd_install(target_proc, target_fd, file); - trace_binder_transaction_fd(t, fp->fd, target_fd); - binder_debug(BINDER_DEBUG_TRANSACTION, - " fd %d -> %d\n", fp->fd, - target_fd); - /* TODO: fput? */ fp->pad_binder = 0; fp->fd = target_fd; } break; @@ -1808,12 +1848,7 @@ static void binder_transaction(struct binder_proc *proc, wake_up_interruptible(target_wait); return; -err_get_unused_fd_failed: -err_fget_failed: -err_fd_not_allowed: -err_binder_get_ref_for_node_failed: -err_binder_get_ref_failed: -err_binder_new_node_failed: +err_translate_failed: err_bad_object_type: err_bad_offset: err_copy_data_failed: