Date: Tue, 7 Mar 2006 16:41:59 GMT From: Todd Miller <millert@FreeBSD.org> To: Perforce Change Reviews <perforce@freebsd.org> Subject: PERFORCE change 92918 for review Message-ID: <200603071641.k27GfxZa006020@repoman.freebsd.org>
next in thread | raw e-mail | index | archive | help
http://perforce.freebsd.org/chv.cgi?CH=92918 Change 92918 by millert@millert_ibook on 2006/03/07 16:41:27 Check to make sure the port is not dead before we use it. This fixes a race condition between label handle deallocation and user space requests using the label handle's port (such as mach_get_label_text). Affected files ... .. //depot/projects/trustedbsd/sedarwin7/src/darwin/xnu/osfmk/ipc/mach_port.c#7 edit .. //depot/projects/trustedbsd/sedarwin7/src/darwin/xnu/osfmk/kern/security.c#7 edit Differences ... ==== //depot/projects/trustedbsd/sedarwin7/src/darwin/xnu/osfmk/ipc/mach_port.c#7 (text+ko) ==== @@ -1773,6 +1773,7 @@ ipc_port_t port; struct label outl; kern_return_t kr; + int dead; if (!MACH_PORT_VALID(name)) return KERN_INVALID_NAME; @@ -1782,10 +1783,16 @@ if (kr != KERN_SUCCESS) return kr; - /* Make sure we are not dealing with a label handle. */ port = (ipc_port_t) entry->ie_object; - ip_lock(port); + dead = ipc_right_check(space, port, name, entry); + if (dead) { + is_write_unlock(space); + return KERN_INVALID_RIGHT; + } + /* port is now locked */ + is_write_unlock(space); + /* Make sure we are not dealing with a label handle. */ if (ip_kotype(port) == IKOT_LABELH) { /* already is a label handle! */ ip_unlock(port); @@ -1813,6 +1820,7 @@ ipc_entry_t entry; kern_return_t kr; struct label *l; + int dead; if (space == IS_NULL || space->is_task == NULL) return KERN_INVALID_TASK; @@ -1824,15 +1832,21 @@ if (kr != KERN_SUCCESS) return kr; - io_lock(entry->ie_object); - is_write_unlock (space); + dead = ipc_right_check(space, entry->ie_object, name, entry); + if (dead) { + is_write_unlock(space); + return KERN_INVALID_RIGHT; + } + /* object (port) is now locked */ + + is_write_unlock(space); l = io_getlabel(entry->ie_object); - mac_externalize_port_label (l, policies, outlabel, 512, 0); + mac_externalize_port_label(l, policies, outlabel, 512, 0); io_unlocklabel(entry->ie_object); - io_unlock (entry->ie_object); - return 0; + io_unlock(entry->ie_object); + return KERN_SUCCESS; } kern_return_t ==== //depot/projects/trustedbsd/sedarwin7/src/darwin/xnu/osfmk/kern/security.c#7 (text+ko) ==== @@ -47,7 +47,7 @@ lh->lh_port->ip_srights++; ip_reference(lh->lh_port); ip_unlock(lh->lh_port); - kr = ipc_object_copyout(space, lh->lh_port, + kr = ipc_object_copyout(space, (ipc_object_t) lh->lh_port, MACH_MSG_TYPE_PORT_SEND, 0, outlabel); if (kr != KERN_SUCCESS) { ip_lock(lh->lh_port); @@ -146,6 +146,7 @@ ipc_object_t objp; kern_return_t kr; struct label *objl; + int dead; if (space == IS_NULL || space->is_task == NULL) return KERN_INVALID_TASK; @@ -166,6 +167,13 @@ return kr; } + dead = ipc_right_check(space, entry->ie_object, obj, entry); + if (dead) { + is_write_unlock(space); + mac_destroy_task_label(&subjl); + return KERN_INVALID_RIGHT; + } + objp = entry->ie_object; io_lock (objp); is_write_unlock (space);
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?200603071641.k27GfxZa006020>