diff options
Diffstat (limited to 'drivers/android')
| -rw-r--r-- | drivers/android/binder.c | 158 |
1 files changed, 109 insertions, 49 deletions
diff --git a/drivers/android/binder.c b/drivers/android/binder.c index 3c71b982bf2a..331d2abca9a2 100644 --- a/drivers/android/binder.c +++ b/drivers/android/binder.c @@ -145,6 +145,11 @@ module_param_call(stop_on_user_error, binder_set_stop_on_user_error, binder_stop_on_user_error = 2; \ } while (0) +#define to_flat_binder_object(hdr) \ + container_of(hdr, struct flat_binder_object, hdr) + +#define to_binder_fd_object(hdr) container_of(hdr, struct binder_fd_object, hdr) + enum binder_stat_types { BINDER_STAT_PROC, BINDER_STAT_THREAD, @@ -1240,6 +1245,47 @@ static void binder_send_failed_reply(struct binder_transaction *t, } } +/** + * binder_validate_object() - checks for a valid metadata object in a buffer. + * @buffer: binder_buffer that we're parsing. + * @offset: offset in the buffer at which to validate an object. + * + * Return: If there's a valid metadata object at @offset in @buffer, the + * size of that object. Otherwise, it returns zero. + */ +static size_t binder_validate_object(struct binder_buffer *buffer, u64 offset) +{ + /* Check if we can read a header first */ + struct binder_object_header *hdr; + size_t object_size = 0; + + if (offset > buffer->data_size - sizeof(*hdr) || + buffer->data_size < sizeof(*hdr) || + !IS_ALIGNED(offset, sizeof(u32))) + return 0; + + /* Ok, now see if we can read a complete object. */ + hdr = (struct binder_object_header *)(buffer->data + offset); + switch (hdr->type) { + case BINDER_TYPE_BINDER: + case BINDER_TYPE_WEAK_BINDER: + case BINDER_TYPE_HANDLE: + case BINDER_TYPE_WEAK_HANDLE: + object_size = sizeof(struct flat_binder_object); + break; + case BINDER_TYPE_FD: + object_size = sizeof(struct binder_fd_object); + break; + default: + return 0; + } + if (offset <= buffer->data_size - object_size && + buffer->data_size >= object_size) + return object_size; + else + return 0; +} + static void binder_transaction_buffer_release(struct binder_proc *proc, struct binder_buffer *buffer, binder_size_t *failed_at) @@ -1262,21 +1308,23 @@ static void binder_transaction_buffer_release(struct binder_proc *proc, else off_end = (void *)offp + buffer->offsets_size; for (; offp < off_end; offp++) { - struct flat_binder_object *fp; + struct binder_object_header *hdr; + size_t object_size = binder_validate_object(buffer, *offp); - if (*offp > buffer->data_size - sizeof(*fp) || - buffer->data_size < sizeof(*fp) || - !IS_ALIGNED(*offp, sizeof(u32))) { - pr_err("transaction release %d bad offset %lld, size %zd\n", + if (object_size == 0) { + pr_err("transaction release %d bad object at offset %lld, size %zd\n", debug_id, (u64)*offp, buffer->data_size); continue; } - fp = (struct flat_binder_object *)(buffer->data + *offp); - switch (fp->type) { + hdr = (struct binder_object_header *)(buffer->data + *offp); + switch (hdr->type) { case BINDER_TYPE_BINDER: case BINDER_TYPE_WEAK_BINDER: { - struct binder_node *node = binder_get_node(proc, fp->binder); + struct flat_binder_object *fp; + struct binder_node *node; + fp = to_flat_binder_object(hdr); + node = binder_get_node(proc, fp->binder); if (node == NULL) { pr_err("transaction release %d bad node %016llx\n", debug_id, (u64)fp->binder); @@ -1285,15 +1333,17 @@ static void binder_transaction_buffer_release(struct binder_proc *proc, binder_debug(BINDER_DEBUG_TRANSACTION, " node %d u%016llx\n", node->debug_id, (u64)node->ptr); - binder_dec_node(node, fp->type == BINDER_TYPE_BINDER, 0); + binder_dec_node(node, hdr->type == BINDER_TYPE_BINDER, + 0); } 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, - fp->type == BINDER_TYPE_HANDLE); - + hdr->type == BINDER_TYPE_HANDLE); if (ref == NULL) { pr_err("transaction release %d bad handle %d\n", debug_id, fp->handle); @@ -1302,19 +1352,21 @@ static void binder_transaction_buffer_release(struct binder_proc *proc, binder_debug(BINDER_DEBUG_TRANSACTION, " ref %d desc %d (node %d)\n", ref->debug_id, ref->desc, ref->node->debug_id); - binder_dec_ref(ref, fp->type == BINDER_TYPE_HANDLE); + binder_dec_ref(ref, hdr->type == BINDER_TYPE_HANDLE); } break; - case BINDER_TYPE_FD: + case BINDER_TYPE_FD: { + struct binder_fd_object *fp = to_binder_fd_object(hdr); + binder_debug(BINDER_DEBUG_TRANSACTION, - " fd %d\n", fp->handle); + " fd %d\n", fp->fd); if (failed_at) - task_close_fd(proc, fp->handle); - break; + task_close_fd(proc, fp->fd); + } break; default: pr_err("transaction release %d bad object type %x\n", - debug_id, fp->type); + debug_id, hdr->type); break; } } @@ -1531,28 +1583,29 @@ static void binder_transaction(struct binder_proc *proc, off_end = (void *)offp + tr->offsets_size; off_min = 0; for (; offp < off_end; offp++) { - struct flat_binder_object *fp; + struct binder_object_header *hdr; + size_t object_size = binder_validate_object(t->buffer, *offp); - if (*offp > t->buffer->data_size - sizeof(*fp) || - *offp < off_min || - t->buffer->data_size < sizeof(*fp) || - !IS_ALIGNED(*offp, sizeof(u32))) { - binder_user_error("%d:%d got transaction with invalid offset, %lld (min %lld, max %lld)\n", + if (object_size == 0 || *offp < off_min) { + binder_user_error("%d:%d got transaction with invalid offset (%lld, min %lld max %lld) or object.\n", proc->pid, thread->pid, (u64)*offp, (u64)off_min, - (u64)(t->buffer->data_size - - sizeof(*fp))); + (u64)t->buffer->data_size); return_error = BR_FAILED_REPLY; goto err_bad_offset; } - fp = (struct flat_binder_object *)(t->buffer->data + *offp); - off_min = *offp + sizeof(struct flat_binder_object); - switch (fp->type) { + + hdr = (struct binder_object_header *)(t->buffer->data + *offp); + off_min = *offp + object_size; + switch (hdr->type) { case BINDER_TYPE_BINDER: case BINDER_TYPE_WEAK_BINDER: { + struct flat_binder_object *fp; + struct binder_node *node; struct binder_ref *ref; - struct binder_node *node = binder_get_node(proc, fp->binder); + 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) { @@ -1580,14 +1633,14 @@ static void binder_transaction(struct binder_proc *proc, return_error = BR_FAILED_REPLY; goto err_binder_get_ref_for_node_failed; } - if (fp->type == BINDER_TYPE_BINDER) - fp->type = BINDER_TYPE_HANDLE; + if (hdr->type == BINDER_TYPE_BINDER) + hdr->type = BINDER_TYPE_HANDLE; else - fp->type = BINDER_TYPE_WEAK_HANDLE; + hdr->type = BINDER_TYPE_WEAK_HANDLE; fp->binder = 0; fp->handle = ref->desc; fp->cookie = 0; - binder_inc_ref(ref, fp->type == BINDER_TYPE_HANDLE, + binder_inc_ref(ref, hdr->type == BINDER_TYPE_HANDLE, &thread->todo); trace_binder_transaction_node_to_ref(t, node, ref); @@ -1598,11 +1651,12 @@ static void binder_transaction(struct binder_proc *proc, } 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, - fp->type == BINDER_TYPE_HANDLE); - + hdr->type == BINDER_TYPE_HANDLE); if (ref == NULL) { binder_user_error("%d:%d got transaction with invalid handle, %d\n", proc->pid, @@ -1616,13 +1670,15 @@ static void binder_transaction(struct binder_proc *proc, goto err_binder_get_ref_failed; } if (ref->node->proc == target_proc) { - if (fp->type == BINDER_TYPE_HANDLE) - fp->type = BINDER_TYPE_BINDER; + if (hdr->type == BINDER_TYPE_HANDLE) + hdr->type = BINDER_TYPE_BINDER; else - fp->type = BINDER_TYPE_WEAK_BINDER; + hdr->type = BINDER_TYPE_WEAK_BINDER; fp->binder = ref->node->ptr; fp->cookie = ref->node->cookie; - binder_inc_node(ref->node, fp->type == BINDER_TYPE_BINDER, 0, NULL); + 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", @@ -1639,7 +1695,9 @@ static void binder_transaction(struct binder_proc *proc, fp->binder = 0; fp->handle = new_ref->desc; fp->cookie = 0; - binder_inc_ref(new_ref, fp->type == BINDER_TYPE_HANDLE, NULL); + 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, @@ -1652,25 +1710,26 @@ static void binder_transaction(struct binder_proc *proc, case BINDER_TYPE_FD: { int target_fd; struct file *file; + struct binder_fd_object *fp = to_binder_fd_object(hdr); 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->handle); + 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->handle); + proc->pid, thread->pid, fp->fd); return_error = BR_FAILED_REPLY; goto err_fd_not_allowed; } - file = fget(fp->handle); + file = fget(fp->fd); if (file == NULL) { binder_user_error("%d:%d got transaction with invalid fd, %d\n", - proc->pid, thread->pid, fp->handle); + proc->pid, thread->pid, fp->fd); return_error = BR_FAILED_REPLY; goto err_fget_failed; } @@ -1688,17 +1747,18 @@ static void binder_transaction(struct binder_proc *proc, goto err_get_unused_fd_failed; } task_fd_install(target_proc, target_fd, file); - trace_binder_transaction_fd(t, fp->handle, target_fd); + trace_binder_transaction_fd(t, fp->fd, target_fd); binder_debug(BINDER_DEBUG_TRANSACTION, - " fd %d -> %d\n", fp->handle, target_fd); + " fd %d -> %d\n", fp->fd, + target_fd); /* TODO: fput? */ - fp->binder = 0; - fp->handle = target_fd; + fp->pad_binder = 0; + fp->fd = target_fd; } break; default: binder_user_error("%d:%d got transaction with invalid object type, %x\n", - proc->pid, thread->pid, fp->type); + proc->pid, thread->pid, hdr->type); return_error = BR_FAILED_REPLY; goto err_bad_object_type; } |