On Fri, Nov 9, 2018 at 9:43 PM chouryzhou(周威) <chouryzhou@xxxxxxxxxxx> wrote: > > > > > > > If IPC_NS is disabled, "current-nsporxy->ipc_ns" will also exists, it will be a static > > > reference of "init_ipc_ns" (in ipc/msgutil.c, not defined in binder.c by me) with > > > no namespace-ization. You will get the same one in all processes, everything is > > > the same as without this patch. > > > > except, as far as I can tell, binder_init_ns() would never have been > > called on it so the mutex and list heads are not initialized so its > > completely broken. Am I missing something? How do those fields get > > initialized in this case? > > > @@ -5832,8 +5888,12 @@ static int __init binder_init(void) > > goto err_init_binder_device_failed; > > } > > > > - return ret; > > + ret = binder_init_ns(&init_ipc_ns); > > + if (ret) > > + goto err_init_namespace_failed; > > > > + return ret; > > They are initialized here. Ok, This init_ipc_ns is a global declared in msgutil.c if SYSVIPC || POSIX_MQUEUE. This seems kinda hacky, but now I finally see why the dependancy... msgutil.c is the only file we can count on if !IPC_NS && (SYSVIPC || POSIX_MQUEUE). There must be a cleaner way to do this, I really don't like this dependency... wouldn't it be cleaner to do: #ifndef CONFIG_IPC_NS static struct ipc_namespace binder_ipc_ns; #define ipcns (&binder_ipc_ns) #else #define ipcns (current->nsproxy->ipc_ns) #endif (and make the initialization of binder_ipc_ns conditional on IPC_NS) This gets us the same thing without the incestuous dependency on the msgutil.c version of init_ipc_ns...and then binder doesn't rely on SYSVIPC or POSIX_MQUEUE directly. > > - choury - > _______________________________________________ devel mailing list devel@xxxxxxxxxxxxxxxxxxxxxx http://driverdev.linuxdriverproject.org/mailman/listinfo/driverdev-devel
