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<p class="MsoNormal">Hi,<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">I’m using UBUS ACL features as my application is in non ROOT group.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">I define <o:p></o:p></p>
<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Courier New"">/usr/share/acl.d/myapp.json<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Courier New""><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Courier New"">{<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Courier New"">"group" : "mygroup",<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Courier New"">"access" : {"methods" : [ "*" ]},<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Courier New"">"publish" : [ "*" ],<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Courier New"">"subscribe" : [ "*" ]<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Courier New"">}<o:p></o:p></span></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Then ubusd crashes.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">By analysis, my app calls<o:p></o:p></p>
<p class="MsoPlainText">ubus_register_event_handler<o:p></o:p></p>
<p class="MsoPlainText">{<o:p></o:p></p>
<p class="MsoPlainText">241 ret = ubus_invoke(ctx, UBUS_SYSTEM_OBJECT_EVENT, "register", b2.head,<o:p></o:p></p>
<p class="MsoPlainText">242 NULL, NULL, 0);<o:p></o:p></p>
<p class="MsoPlainText">}<o:p></o:p></p>
<p class="MsoPlainText"><o:p> </o:p></p>
<p class="MsoPlainText">At server, it crashes at<o:p></o:p></p>
<pre>ubusd_handle_invoke<o:p></o:p></pre>
<p class="MsoPlainText">{<o:p></o:p></p>
<p class="MsoPlainText">if (ubusd_acl_check(cl, obj->path.key, method, UBUS_ACL_ACCESS))<o:p></o:p></p>
<p class="MsoPlainText">}<o:p></o:p></p>
<p class="MsoPlainText"><o:p> </o:p></p>
<p class="MsoPlainText">Here obj(with id UBUS_SYSTEM_OBJECT_EVENT) is an internal object, and with obj->path.key NULL. Inside, UBUS directly use it in strcmp. Some coredump information at last part.<o:p></o:p></p>
<p class="MsoPlainText"><o:p> </o:p></p>
<p class="MsoPlainText">I suggest to modify the above line to <o:p></o:p></p>
<pre>259 if ((blob_get_u32(attr[UBUS_ATTR_OBJID]) != UBUS_SYSTEM_OBJECT_EVENT) && (ubusd_acl_check(cl, obj->path.key, method, UBUS_ACL_ACCESS)))<o:p></o:p></pre>
<p class="MsoPlainText"><o:p> </o:p></p>
<p class="MsoPlainText">After add this, it works well and the event path is checked at other place.<o:p></o:p></p>
<p class="MsoPlainText"><o:p> </o:p></p>
<p class="MsoPlainText">Coredump:<o:p></o:p></p>
<p class="MsoPlainText">#2 0x00402a9c in ubusd_handle_invoke (cl=0x8e30b8, ub=0x8e3e40, attr=0x415230) at<o:p></o:p></p>
<p class="MsoPlainText">ubusd_proto.c:259<o:p></o:p></p>
<p class="MsoPlainText">259 if (ubusd_acl_check(cl, obj->path.key, method, UBUS_ACL_ACCESS))<o:p></o:p></p>
<p class="MsoPlainText">(gdb) info local<o:p></o:p></p>
<p class="MsoPlainText">obj = 0x8df138<o:p></o:p></p>
<p class="MsoPlainText">id = 0x8df138<o:p></o:p></p>
<p class="MsoPlainText">method = 0x8e3e68 "register"<o:p></o:p></p>
<p class="MsoPlainText">(gdb) print *id<o:p></o:p></p>
<p class="MsoPlainText">$25 = {avl = {list = {next = 0x8df1b0, prev = 0x41531c}, parent = 0x8df1b0, left = 0x0, right = 0x0, key = 0x8df154, balance = 0 '\000', leader = true}, id = 1}<o:p></o:p></p>
<p class="MsoPlainText">(gdb) print *obj<o:p></o:p></p>
<p class="MsoPlainText">$26 = {id = {avl = {list = {next = 0x8df1b0, prev = 0x41531c}, parent = 0x8df1b0, left = 0x0, right = 0x0, key = 0x8df154, balance = 0 '\000', leader = true}, id = 1}, list = {<o:p></o:p></p>
<p class="MsoPlainText"> next = 0x8df158, prev = 0x8df158}, events = {next = 0x8df160, prev = 0x8df160}, subscribers = {next = 0x8df168, prev = 0x8df168}, target_list = {next = 0x8df170,
<o:p></o:p></p>
<p class="MsoPlainText"> prev = 0x8df170}, type = 0x0, path = {list = {next = 0x0, prev = 0x0}, parent = 0x0, left = 0x0, right = 0x0, key = 0x0, balance = 0 '\000', leader = false}, client = 0x0,<o:p></o:p></p>
<p class="MsoPlainText"> recv_msg = 0x403940 <ubusd_event_recv>, event_seen = 0, invoke_seq = 0}<o:p></o:p></p>
<p class="MsoPlainText"><o:p> </o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">BR<o:p></o:p></p>
<p class="MsoNormal">Wang Bin<o:p></o:p></p>
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