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Keeping track of thread creation in a process
In some cases, one of our daemons will end up with thousands of threads. Clearly a bug somewhere, but I can't see it in the code. (Admittedly, it's C++ which is a bit alien to me still. Anyway.) If I wanted to just be notified each time a thread was created in the process, what are some ways to do that? I assume dtrace and lldb have ways to od it, but I'm not quite sure what.
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795
Jul ’23
Sonoma on a virtual machine?
I don't have enough physical machines to install Sonoma; I do, however, have lots of CPU cycles, memory, and disk space -- so can I get Sonoma running in VMWare Fusion? Ideally on both AS and Intel. I searched to see if this had been asked, but I will be the first to admit my searching skills are bad. (This is why I like find and grep.)
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2.3k
Jun ’23
Spotlight/metadata can be so very annoying
sef% mdls /Applications/Google\ Chrome.app/Contents/Frameworks/Google\ Chrome\ Framework.framework/Versions/112.0.5615.137/Helpers/Google\ Chrome\ Helper.app kMDItemFSContentChangeDate = 2023-04-17 23:59:16 +0000 kMDItemFSCreationDate = 2023-04-17 23:59:16 +0000 kMDItemFSCreatorCode = "" kMDItemFSFinderFlags = 0 kMDItemFSHasCustomIcon = 0 kMDItemFSInvisible = 0 kMDItemFSIsExtensionHidden = 0 kMDItemFSIsStationery = 0 kMDItemFSLabel = 0 kMDItemFSName = "Google Chrome Helper.app" kMDItemFSNodeCount = 1 kMDItemFSOwnerGroupID = 0 kMDItemFSOwnerUserID = 0 kMDItemFSSize = 1 kMDItemFSTypeCode = "" sef% mdfind 'kMDItemFSName == "Google Chrome Helper.app"' So there's a metadata key that has a value... but mdfind won't find it. I haven't tried writing a small program to see if it would find it yet, although I am somewhat curious if it would.
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784
May ’23
Using WKWebView and a yubikey?
Coworkers are trying it and it's not working -- the google response says there was a problem with it, and not much else. I do not have a yubikey (at least not yet 😄), and I'm really not good at the GUI stuff so I don't know as much about it as I probably should. Searching the fora here found a question and comment that didn't make a lot of sense to me, but again I admit to a lot of ignorance here. So any pointers to where I should be look would be appreciated.
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1.3k
Mar ’23
Given an audit token, can I get the executable path?
I can get the security path "easily" enough, but for bundles, that gives me the top director, whereas I am trying to get the name of the executable. (I would have used kern.proc.pathname.$pid on FreeBSD, but that's not there for macOS, and kern.procname only gives the current process' name. I also found eskimo's post about getting process arguments, and I could use that to get all the arguments and only care about argv[0], but since the kernel does have p->p_name it'd be nice if there were a nicer way to get just that...) This is in the context of a network extension. Endpoint Security is much nicer in that regard. 😄
2
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585
Mar ’23
Transparent app proxy and UDP, redux
When doing UDP communications, the socket can either be connected, or not. If it's not connected, it can use sendto to send it to a different destination, and it can use recvfrom to receive from anywhere. (I honestly don't know how often this is used.) An NEAppProxyUDPFlow does not, as far as I can tell, have any way to tell if it has been connected. In fact, the API involved involves an array of datagrams tied to an array of endpoints. But if the provider and the app do not have the same connected state, the results could be not at all what the app expects. Is that correct? Or is it to be expected that it will only expect to get data from the set of destinations, and only that set?
6
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561
Mar ’23
NWConnection, UDP, and remote address
If I use NWConnection for a UDP connection, is there a way to get the peer name? Since it's not a stream, data can theoretically come from anywhere; at the C level, I'd use recvfrom which would tell me the remote address. I'm likely to be missing something obvious to everyone but me, I do have a tendency to look at problems as C problems. 😄
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551
Mar ’23
xpc api misuse crash
To begin with: I know it's my code, because if I go back to our main branch and try it, I don't get this crash. But I can't figure out what it's unhappy about, so I'm not sure what changes I have to look for. (Also, this is macOS.) The daemon tries to communicate with a Network Extension over XPC. I have a class, with a shared instance, and I have a cached NSXPCConnection connection instance variable. So my code is something like id connection = [[ExtensionCommunication shared] connection], which is created by [[NSXPCConnection alloc] initWithMachServiceName:self.redirectorMachServiceName options:0]. With my changes (whatever they are), when it does [_connection resume], it crashes:   * frame #0: 0x00007ff8191ab20e libxpc.dylib`_xpc_api_misuse + 117     frame #1: 0x00007ff8191963a1 libxpc.dylib`xpc_connection_resume + 54 This happens whether the network extension is activated or not. The crash happens the second time this is called. (Hm, one thing I need to figure out then is why my cached connection object is being set to nil. It shouldn't be. hm.) Anyway! Any suggestions on how I can try to debug this?
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1.2k
Feb ’23
Transparent proxy providers and UDP
This was discussed a bit, but it was a while ago, and I asked recently on the thread, but let's see if I can get more information this way. Normally if you're a process doing UDP I/O, you use a timeout of some sort (usually with recvfrom, or a read with an alarm signal or something). How is a network extension supposed to know that? Or is it supposed to assume that if a process signals done-with-writing, that it should treat both directions as closed? (This is definitely not the case with TCP, of course.) UDP has never really been my strong point in networking programming -- too late to only have it available, and too early to find TCP problematical for my needs. 😄
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497
Feb ’23
C++ missing symbol
#include <stdio.h> #include <sstream> int main(int ac, char **av) { std::__1::basic_ostringstream<char, std::__1::char_traits<char>, std::__1::allocator<char> > x; x << "How now brown cow"; return 0; } If I build this on macOS 12, and try to run the binary on macOS 11, it fails because that symbol is not present in /usr/lib/libc++.1.dylib. If I compile it on macOS 11, and run on 11 or later, it works. Is this correct behaviour? Since the dylib version didn't change, I would expect that to mean no ABI changes.
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1.9k
Feb ’23