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udev and systemd merger #2

Closed
shearl opened this issue Jan 15, 2016 · 3 comments
Closed

udev and systemd merger #2

shearl opened this issue Jan 15, 2016 · 3 comments

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@shearl
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shearl commented Jan 15, 2016

According to the linux-hotplug mailing list, udev and systemd have merged: http:https://lwn.net/Articles/490413/

When udev support isn't found, the pcsc-lite configure script suggests the following options:
install libudev-dev or use --disable-libudev

I think due to the merger libudev-dev is no longer available??

At least on the Pulsar Linux distribution I'm using, libudev-dev is not available through the so-called smart package manager. After discovering that udev and system have merged, I tried installing the package systemd-dev and was able to build and successfully use pcsc-lite + ccid. (But perhaps it was many of the dependencies installed by systemd-dev that did the trick?)

So I think the suggestions in the configure script should be updated to something like:
install libudev-dev (or systemd-dev* for systems with systemd >= 184) or use --disable-libudev

If that's correct, I can commit a pull request if you like.

Or perhaps the configure script can look for either option? (I'm not a configure script expert.)

*Though on other distributions the package might be named libsystemd-dev or systemd-devel.
@LudovicRousseau
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Debian provides systemd version 228 and libudev-dev is still provided.
libsystemd-dev does not provide the pkg-config file libudev.pc used by the check in configure.

Packages names and content will depend on every Linux distribution. I do not plan to write a complete INSTALL documentation in the configure error message. I don't think this proposal is a good idea.

As a developer building pcsc-lite you should be smart enough to know what package to install :-)

LudovicRousseau added a commit that referenced this issue Jan 27, 2017
@LudovicRousseau
SCardCancel(): fix a possible use after free
9a21c82 
From Maksim Ivanov:
" It seems that there are still some issues with regard to the blocking
requests cancellation functionality in PC/SC-Lite:

2. Use-after-free possible in SCardCancel.

   This is probably a low-severity issue, as the deallocated memory will
   be accessed only for reading an int, which would be then used for
   deciding whether to fail fast or to send a request to the daemon
   (the latter is expected to fail anyway).

For #2, the suggestion is to move the reading of the
   currentContextMap->cancellable flag under the clientMutex lock.

   Also it may be advisable to change the SCardGetAndLockContext
   function interface so that it's more difficult to use it in thread-unsafe
   manner: remove the second parameter "int lock" and make the
   locking behavior the default one, and introduce another function
   that does no locks and returns a boolean instead of an
   SCONTEXTMAP* pointer. "

Thanks to Maksim Ivanov for the bug report and solution
"[Pcsclite-muscle] Data races related to SCardCancel"
http:https://lists.alioth.debian.org/pipermail/pcsclite-muscle/Week-of-Mon-20170116/000789.html
@Jean-Baptiste-Lasselle
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Jean-Baptiste-Lasselle commented Jun 21, 2019 •
edited
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According to the linux-hotplug mailing list, udev and systemd have merged: http:https://lwn.net/Articles/490413/

When udev support isn't found, the pcsc-lite configure script suggests the following options:
install libudev-dev or use --disable-libudev

I think due to the merger libudev-dev is no longer available??

At least on the Pulsar Linux distribution I'm using, libudev-dev is not available through the so-called smart package manager. After discovering that udev and system have merged, I tried installing the package systemd-dev and was able to build and successfully use pcsc-lite + ccid. (But perhaps it was many of the dependencies installed by systemd-dev that did the trick?)

So I think the suggestions in the configure script should be updated to something like:
install libudev-dev (or systemd-dev* for systems with systemd >= 184) or use --disable-libudev

If that's correct, I can commit a pull request if you like.

Or perhaps the configure script can look for either option? (I'm not a configure script expert.)

*Though on other distributions the package might be named libsystemd-dev or systemd-devel.

Oh My, thank you so much  @shearl , I am currently working on setting up a special K8S cluster, running a very specific App, using Smart Cards, so I have to provision labeled smart-card-enablded" K8S cluster nodes, and damn :
If I finally di not end up on your question here, I would nbever have been able to install pc sc lite package to finally make my Smart Card drivers work, so thank you SO MUCH, for this question and your infos !

Details :
I setup my prototype using Debian Stretch, and Oh My, I ran into a Smartcard socket not found, disabling err="stat /run/pcscd/pcscd.comm: no such file or directory error....

So I installed pc sc lite package, to get the driver in my system, so I can go back to real serious wokr in K8S. And I foolowed the following recipe (which worked thanks to you @shearl 👍 ) :

#!/bin/bash

export OPS_HOME=~/.ethereum-test
export PACKAGE_SOURCE_GIT_URI=https://salsa.debian.org/debian/pcsc-lite.git

mkdir -p $OPS_HOME/.pcsc-lite
cd $OPS_HOME/.pcsc-lite
git clone "$PACKAGE_SOURCE_GIT_URI" .

# Briefly, the shell command './configure && make && make install'  should configure, build, AND install this package.
# see. https://salsa.debian.org/debian/pcsc-lite/blob/master/INSTALL

# beware, guys, the star character below is quite important, see man apt-get
sudo apt-get install -y systemd-dev*
sudo ./configure && sudo make && sudo make install

After executing that, here is what I got :

jbl@poste-devops-typique:~/.ethereum-test/.pcsc-lite$ sudo systemctl status pcscd
[sudo] password for jbl: 
● pcscd.service - PC/SC Smart Card Daemon
   Loaded: loaded (/lib/systemd/system/pcscd.service; indirect; vendor preset: enabled)
   Active: inactive (dead)
     Docs: man:pcscd(8)
jbl@poste-devops-typique:~/.ethereum-test/.pcsc-lite$ # Ouh, and btw : 
jbl@poste-devops-typique:~/.ethereum-test/abovetest/provisioning$ uname -a
Linux poste-devops-typique 4.9.0-8-amd64 #1 SMP Debian 4.9.130-2 (2018-10-27) x86_64 GNU/Linux

At any rate @shearl , if you're curious what I was working on : https://github.com/Jean-Baptiste-Lasselle/ethereum-test/edit/master/README.md

Well I do need that driver installed, it is a hardware requirements from the app I am using, so here is a case @LudovicRousseau , where, I think you might be a bit harsh with us, there :

No, I don't think that only developers should be able to solve that problem, because build from source, is the only way I found to provision the pc sc lite driver inside my OS.

@LudovicRousseau Vous trouverez même uune preuve de sincérité : https://github.com/Jean-Baptiste-Lasselle/ethereum-test/edit/master/README.md
vous pourrez y lire que je m'atttendais à vous devoir un énorme merci.

Je vous le transmets, parce que sans votre travail, je n'aurais rien trouvé, mais suis en désaccord avec vous sur cette vision du "tu es développeur, tu dois savoir débogguer ça tout seul, même si la doc n'indique rien"...

The funniest and most common eventuality

Well to make it all fun After I finally could master pc sc lite, I could rigourously verify that my App's problem has nothing to do with pcscd, since reprovisiononing that didn't change one line of logs and outputs...

:)

But now I know What A smart Card is, and pretty much how to PXE boot a Smart Card ready machine, on Debian Stretch ^^

Thanks to your works, dear pairs. So thank you, better knowing exactly what you don't know, than not knowing what you don't (nooooo).

Regards

ps.: (n update)

Well I might write another update in a few days, since I think I found something, like my app is looking for the socket in the wong folder...

@LudovicRousseau
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@Jean-Baptiste-Lasselle No need to rebuild pcsc-lite from source code. Just install the pcscd package on a Debian system.
Also no need to run ./configure and make with sudo. It is a dangerous idea. Please do not document that in your https://github.com/Jean-Baptiste-Lasselle/ethereum-test/blob/master/README.md.

@shearl On Debian the libudev-dev package is still provided and will be for some more time I think. I can't give the package name for every existing GNU/Linux distribution. Sorry for that. I ask the user to be smart.

LudovicRousseau added a commit that referenced this issue Dec 15, 2021
@LudovicRousseau
pcscdaemon.c: Fix data race for AraKiri variable
e46aad0 
Issue reported by clang ThreadSanitizer

WARNING: ThreadSanitizer: data race (pid=14419)
  Read of size 1 at 0x000000f3a9c8 by main thread:
    #0 SVCServiceRunLoop <null> (pcscd+0x4c0da9)
    #1 main <null> (pcscd+0x4c0694)

  Previous write of size 1 at 0x000000f3a9c8 by thread T1:
    #0 signal_thread <null> (pcscd+0x4c0aca)

  As if synchronized via sleep:
    #0 nanosleep <null> (pcscd+0x4297dd)
    #1 SYS_USleep <null> (pcscd+0x4c6c36)
    #2 SVCServiceRunLoop <null> (pcscd+0x4c0cef)
    #3 main <null> (pcscd+0x4c0694)

  Location is global 'AraKiri' of size 1 at 0x000000f3a9c8 (pcscd+0x000000f3a9c8)

  Thread T1 (tid=14421, running) created by main thread at:
    #0 pthread_create <null> (pcscd+0x42be9b)
    #1 main <null> (pcscd+0x4c01c8)

SUMMARY: ThreadSanitizer: data race (/home/rousseau/sc/costa/PCSC/src/pcscd+0x4c0da9) in SVCServiceRunLoop
LudovicRousseau pushed a commit that referenced this issue Dec 15, 2021
@andrei-datcu @LudovicRousseau
Fix data races in EHStatusHandlerThread()
8434617 
Problem:
The thread running EHStatusHandlerThread() will race all the
rContext->readerState->fields as well as the powerState and some other
flags. These flags are both consumed and set by the thread running the
ccid driver as well.

Solution:
Make the flow unidirectional*: the status thread will always set its own
copy and "stash" a unique copy ready to be consumed by the driver
thread. That copy is consumed and rcontext->readerState is updated in
RFCheckReaderStatus() and a few other functions in readerfactory.c.
Whenever a copy is consumed it is also freed. Note that even though this
adds dynamic allocation it's at most 2 instances of READER_STATE.

This PR uses the C11 _Atomic feature. I'm not very familiar with all the
compilers pcsc is built with, but if you deem this to be incompatible,
please review the overall approach and I can #ifdef and do some mutexes
for platforms which do not provide _Atomic

* the flow is unidirectional except for the readerName which is logged
  at the beginning of the status thread. That should not be a problem
  since the name is set from the driver thread before the status thread
  is spawned.

==================
WARNING: ThreadSanitizer: data race (pid=28786)
  Write of size 4 at 0x000000f55c10 by thread T3:
    #0 EHStatusHandlerThread <null> (pcscd+0x4c3aed)

  Previous read of size 4 at 0x000000f55c10 by main thread:
    #0 RFWaitForReaderInit <null> (pcscd+0x4d0e27)
    #1 main <null> (pcscd+0x4c70c6)

  Location is global 'readerStates' of size 2944 at 0x000000f55b60 (pcscd+0x000000f55c10)

  Thread T3 (tid=28790, running) created by main thread at:
    #0 pthread_create <null> (pcscd+0x42be9b)
    #1 ThreadCreate <null> (pcscd+0x4e1c79)
    #2 EHSpawnEventHandler <null> (pcscd+0x4c2e9f)
    #3 RFAddReader <null> (pcscd+0x4cac07)
    #4 HPAddDevice <null> (pcscd+0x4e0a2e)
    #5 HPScanUSB <null> (pcscd+0x4dfe65)
    #6 HPRegisterForHotplugEvents <null> (pcscd+0x4dfd3a)
    #7 main <null> (pcscd+0x4c705c)

SUMMARY: ThreadSanitizer: data race (/home/rousseau/sc/costa/PCSC/src/pcscd+0x4c3aed) in EHStatusHandlerThread
==================
LudovicRousseau added a commit that referenced this issue Dec 15, 2021
@LudovicRousseau
Fix race with dwEventStatus
1060937 
The problem is (in part) with the switch() that may read the variable
more than once.

==================
WARNING: ThreadSanitizer: data race (pid=10828)
  Write of size 8 at 0x7b040000ae78 by thread T6 (mutexes: write M0):
    #0 RFSetReaderEventState PCSC/src/readerfactory.c:1321:32 (pcscd+0x4c45ce)
    #1 EHStatusHandlerThread PCSC/src/eventhandler.c:382:11 (pcscd+0x4bee54)

  Previous read of size 8 at 0x7b040000ae78 by thread T8:
    #0 RFCheckReaderEventState PCSC/src/readerfactory.c:1350:24 (pcscd+0x4c46c6)
    #1 SCardStatus PCSC/src/winscard.c:1286:7 (pcscd+0x4ce7b5)
    #2 ContextThread PCSC/src/winscard_svc.c:635:16 (pcscd+0x4d0cc1)

  Location is heap block of size 16 at 0x7b040000ae70 allocated by thread T8:
    #0 malloc <null> (pcscd+0x42a65c)
    #1 RFAddReaderHandle PCSC/src/readerfactory.c:1249:14 (pcscd+0x4c43b4)
    #2 SCardConnect PCSC/src/winscard.c:491:7 (pcscd+0x4ccc16)
    #3 ContextThread PCSC/src/winscard_svc.c:502:16 (pcscd+0x4d0a70)

  Mutex M0 (0x7b4c000000a0) created at:
    #0 pthread_mutex_init <null> (pcscd+0x42d2fd)
    #1 RFAddReader PCSC/src/readerfactory.c:329:8 (pcscd+0x4c1d18)
    #2 HPAddDevice PCSC/src/hotplug_libudev.c:534:8 (pcscd+0x4cba1c)
    #3 HPEstablishUSBNotifications PCSC/src/hotplug_libudev.c:668:6 (pcscd+0x4cb4d4)

  Thread T6 (tid=11122, running) created by thread T2 at:
    #0 pthread_create <null> (pcscd+0x42be8b)
    #1 ThreadCreate PCSC/src/utils.c:184:8 (pcscd+0x4cc2dc)
    #2 EHSpawnEventHandler PCSC/src/eventhandler.c:237:7 (pcscd+0x4beb59)
    #3 RFAddReader PCSC/src/readerfactory.c:426:8 (pcscd+0x4c21b9)
    #4 HPAddDevice PCSC/src/hotplug_libudev.c:534:8 (pcscd+0x4cba1c)
    #5 HPEstablishUSBNotifications PCSC/src/hotplug_libudev.c:668:6 (pcscd+0x4cb4d4)

  Thread T8 (tid=11173, running) created by main thread at:
    #0 pthread_create <null> (pcscd+0x42be8b)
    #1 ThreadCreate PCSC/src/utils.c:184:8 (pcscd+0x4cc2dc)
    #2 CreateContextThread PCSC/src/winscard_svc.c:236:7 (pcscd+0x4cfd8b)
    #3 SVCServiceRunLoop PCSC/src/pcscdaemon.c:134:9 (pcscd+0x4c1082)
    #4 main PCSC/src/pcscdaemon.c:786:2 (pcscd+0x4c09c4)

SUMMARY: ThreadSanitizer: data race PCSC/src/readerfactory.c:1321:32 in RFSetReaderEventState
==================
LudovicRousseau added a commit that referenced this issue Dec 19, 2021
@LudovicRousseau
Fix race with dwEventStatus
c2d6e38 
The problem is (in part) with the switch() that may read the variable
more than once.

==================
WARNING: ThreadSanitizer: data race (pid=10828)
  Write of size 8 at 0x7b040000ae78 by thread T6 (mutexes: write M0):
    #0 RFSetReaderEventState PCSC/src/readerfactory.c:1321:32 (pcscd+0x4c45ce)
    #1 EHStatusHandlerThread PCSC/src/eventhandler.c:382:11 (pcscd+0x4bee54)

  Previous read of size 8 at 0x7b040000ae78 by thread T8:
    #0 RFCheckReaderEventState PCSC/src/readerfactory.c:1350:24 (pcscd+0x4c46c6)
    #1 SCardStatus PCSC/src/winscard.c:1286:7 (pcscd+0x4ce7b5)
    #2 ContextThread PCSC/src/winscard_svc.c:635:16 (pcscd+0x4d0cc1)

  Location is heap block of size 16 at 0x7b040000ae70 allocated by thread T8:
    #0 malloc <null> (pcscd+0x42a65c)
    #1 RFAddReaderHandle PCSC/src/readerfactory.c:1249:14 (pcscd+0x4c43b4)
    #2 SCardConnect PCSC/src/winscard.c:491:7 (pcscd+0x4ccc16)
    #3 ContextThread PCSC/src/winscard_svc.c:502:16 (pcscd+0x4d0a70)

  Mutex M0 (0x7b4c000000a0) created at:
    #0 pthread_mutex_init <null> (pcscd+0x42d2fd)
    #1 RFAddReader PCSC/src/readerfactory.c:329:8 (pcscd+0x4c1d18)
    #2 HPAddDevice PCSC/src/hotplug_libudev.c:534:8 (pcscd+0x4cba1c)
    #3 HPEstablishUSBNotifications PCSC/src/hotplug_libudev.c:668:6 (pcscd+0x4cb4d4)

  Thread T6 (tid=11122, running) created by thread T2 at:
    #0 pthread_create <null> (pcscd+0x42be8b)
    #1 ThreadCreate PCSC/src/utils.c:184:8 (pcscd+0x4cc2dc)
    #2 EHSpawnEventHandler PCSC/src/eventhandler.c:237:7 (pcscd+0x4beb59)
    #3 RFAddReader PCSC/src/readerfactory.c:426:8 (pcscd+0x4c21b9)
    #4 HPAddDevice PCSC/src/hotplug_libudev.c:534:8 (pcscd+0x4cba1c)
    #5 HPEstablishUSBNotifications PCSC/src/hotplug_libudev.c:668:6 (pcscd+0x4cb4d4)

  Thread T8 (tid=11173, running) created by main thread at:
    #0 pthread_create <null> (pcscd+0x42be8b)
    #1 ThreadCreate PCSC/src/utils.c:184:8 (pcscd+0x4cc2dc)
    #2 CreateContextThread PCSC/src/winscard_svc.c:236:7 (pcscd+0x4cfd8b)
    #3 SVCServiceRunLoop PCSC/src/pcscdaemon.c:134:9 (pcscd+0x4c1082)
    #4 main PCSC/src/pcscdaemon.c:786:2 (pcscd+0x4c09c4)

SUMMARY: ThreadSanitizer: data race PCSC/src/readerfactory.c:1321:32 in RFSetReaderEventState
==================
@wmaroulis wmaroulis mentioned this issue Jul 24, 2022
Closed
LudovicRousseau added a commit that referenced this issue Nov 19, 2023
@LudovicRousseau
Access readerStates[] in a thread safe way
e12d9dd 
protect accesses to readerStates[] using a mutex so that 2 threads cannot
interfere for example by calling SCardGetStatusChange() and
SCardStatus() at the same time.

The ThreadSanitizer trace was:
==================
WARNING: ThreadSanitizer: data race (pid=13125)
  Write of size 8 at 0x7fd3afc2b040 by main thread (mutexes: write M0):
    #0 read <null> (pcsc_demo+0x5d8a4) (BuildId: 1ce759cdf5448d9e6401e93f7f56d4c7caa8ede7)
    #1 read /usr/include/x86_64-linux-gnu/bits/unistd.h:38:10 (libpcsclite.so.1+0xab3c) (BuildId: 53195794f51c4d60ff5688d377d82ae2e264554e)
    #2 MessageReceive src/winscard_msg.c:491:17 (libpcsclite.so.1+0xab3c)
    #3 getReaderStates src/winscard_clnt.c:3552:7 (libpcsclite.so.1+0x4109) (BuildId: 53195794f51c4d60ff5688d377d82ae2e264554e)
    #4 SCardStatus src/winscard_clnt.c:1441:7 (libpcsclite.so.1+0x4109)
    #5 main /tmp/x/pcsc-lite-2.0.0/pcsc_demo.c:108:7 (pcsc_demo+0xd1bc4) (BuildId: 1ce759cdf5448d9e6401e93f7f56d4c7caa8ede7)

  Previous write of size 8 at 0x7fd3afc2b040 by thread T1 (mutexes: write M1):
    #0 read <null> (pcsc_demo+0x5d8a4) (BuildId: 1ce759cdf5448d9e6401e93f7f56d4c7caa8ede7)
    #1 read /usr/include/x86_64-linux-gnu/bits/unistd.h:38:10 (libpcsclite.so.1+0xab3c) (BuildId: 53195794f51c4d60ff5688d377d82ae2e264554e)
    #2 MessageReceive src/winscard_msg.c:491:17 (libpcsclite.so.1+0xab3c)
    #3 getReaderStatesAndRegisterForEvents src/winscard_clnt.c:3571:7 (libpcsclite.so.1+0x47b3) (BuildId: 53195794f51c4d60ff5688d377d82ae2e264554e)
    #4 SCardGetStatusChange src/winscard_clnt.c:1747:7 (libpcsclite.so.1+0x47b3)
    #5 do_statuschange /tmp/x/pcsc-lite-2.0.0/pcsc_demo.c:35:10 (pcsc_demo+0xd1e6d) (BuildId: 1ce759cdf5448d9e6401e93f7f56d4c7caa8ede7)
    #6 statuschange_thread /tmp/x/pcsc-lite-2.0.0/pcsc_demo.c:53:2 (pcsc_demo+0xd19fd) (BuildId: 1ce759cdf5448d9e6401e93f7f56d4c7caa8ede7)

  Location is global 'readerStates' of size 2944 at 0x7fd3afc2b040 (libpcsclite.so.1+0xf040)

  Mutex M0 (0x7b3000006010) created at:
    #0 pthread_mutex_init <null> (pcsc_demo+0x5431f) (BuildId: 1ce759cdf5448d9e6401e93f7f56d4c7caa8ede7)
    #1 SCardAddContext src/winscard_clnt.c:3259:8 (libpcsclite.so.1+0x6adc) (BuildId: 53195794f51c4d60ff5688d377d82ae2e264554e)
    #2 SCardEstablishContextTH src/winscard_clnt.c:659:7 (libpcsclite.so.1+0x6adc)
    #3 SCardEstablishContext src/winscard_clnt.c:483:7 (libpcsclite.so.1+0x6adc)
    #4 main /tmp/x/pcsc-lite-2.0.0/pcsc_demo.c:86:7 (pcsc_demo+0xd1aca) (BuildId: 1ce759cdf5448d9e6401e93f7f56d4c7caa8ede7)

  Mutex M1 (0x7b3000000010) created at:
    #0 pthread_mutex_init <null> (pcsc_demo+0x5431f) (BuildId: 1ce759cdf5448d9e6401e93f7f56d4c7caa8ede7)
    #1 SCardAddContext src/winscard_clnt.c:3259:8 (libpcsclite.so.1+0x6adc) (BuildId: 53195794f51c4d60ff5688d377d82ae2e264554e)
    #2 SCardEstablishContextTH src/winscard_clnt.c:659:7 (libpcsclite.so.1+0x6adc)
    #3 SCardEstablishContext src/winscard_clnt.c:483:7 (libpcsclite.so.1+0x6adc)
    #4 do_statuschange /tmp/x/pcsc-lite-2.0.0/pcsc_demo.c:12:7 (pcsc_demo+0xd1d84) (BuildId: 1ce759cdf5448d9e6401e93f7f56d4c7caa8ede7)
    #5 statuschange_thread /tmp/x/pcsc-lite-2.0.0/pcsc_demo.c:53:2 (pcsc_demo+0xd19fd) (BuildId: 1ce759cdf5448d9e6401e93f7f56d4c7caa8ede7)

  Thread T1 (tid=13127, running) created by main thread at:
    #0 pthread_create <null> (pcsc_demo+0x52b4d) (BuildId: 1ce759cdf5448d9e6401e93f7f56d4c7caa8ede7)
    #1 start_thread /tmp/x/pcsc-lite-2.0.0/pcsc_demo.c:61:6 (pcsc_demo+0xd1964) (BuildId: 1ce759cdf5448d9e6401e93f7f56d4c7caa8ede7)
    #2 main /tmp/x/pcsc-lite-2.0.0/pcsc_demo.c:84:8 (pcsc_demo+0xd1ab1) (BuildId: 1ce759cdf5448d9e6401e93f7f56d4c7caa8ede7)

SUMMARY: ThreadSanitizer: data race (/tmp/x/pcsc-lite-2.0.0/pcsc_demo+0x5d8a4) (BuildId: 1ce759cdf5448d9e6401e93f7f56d4c7caa8ede7) in __interceptor_read
==================

Thanks to Stefan Ehmann for the bug report.
LudovicRousseau added a commit that referenced this issue Nov 19, 2023
@LudovicRousseau
Initialize socketName in a thread safe way
9466fc0 
Use pthread_once() to initialize the variable only once.
It was possible that 2 threads were modifying the variable at the same
time.

The ThreadSanitizer trace was:
==================
WARNING: ThreadSanitizer: data race (pid=14864)
  Write of size 1 at 0x7f8803cccd2b by main thread:
    #0 getSocketName src/winscard_msg.c:101 (libpcsclite.so.1+0xa28c)
    #1 getSocketName src/winscard_msg.c:85 (libpcsclite.so.1+0xa28c)
    #2 SCardCheckDaemonAvailability src/winscard_clnt.c:3550 (libpcsclite.so.1+0x65cf)
    #3 SCardEstablishContext src/winscard_clnt.c:479 (libpcsclite.so.1+0x66a7)
    #4 main /tmp/pcsc/pcsc_demo.cpp:86 (pcsc_demo+0x1517)

  Previous write of size 1 at 0x7f8803cccd2b by thread T1:
    #0 getSocketName src/winscard_msg.c:101 (libpcsclite.so.1+0xa28c)
    #1 getSocketName src/winscard_msg.c:85 (libpcsclite.so.1+0xa28c)
    #2 SCardCheckDaemonAvailability src/winscard_clnt.c:3550 (libpcsclite.so.1+0x65cf)
    #3 SCardEstablishContext src/winscard_clnt.c:479 (libpcsclite.so.1+0x66a7)
    #4 do_statuschange /tmp/pcsc/pcsc_demo.cpp:12 (pcsc_demo+0x1264)
    #5 statuschange_thread /tmp/pcsc/pcsc_demo.cpp:53 (pcsc_demo+0x1264)

  Location is global '<null>' at 0x000000000000 (libpcsclite.so.1+0xfd2b)

  Thread T1 (tid=14867, running) created by main thread at:
    #0 pthread_create ../../../../src/libsanitizer/tsan/tsan_interceptors_posix.cpp:1001 (libtsan.so.2+0x5e686)
    #1 start_thread(char const*) /tmp/pcsc/pcsc_demo.cpp:61 (pcsc_demo+0x1432)
    #2 main /tmp/pcsc/pcsc_demo.cpp:84 (pcsc_demo+0x14cc)

SUMMARY: ThreadSanitizer: data race src/winscard_msg.c:101 in getSocketName
==================
ThreadSanitizer: reported 1 warnings

Thanks to Stefan Ehmann for the bug report.
LudovicRousseau added a commit that referenced this issue Nov 19, 2023
@LudovicRousseau
Access cardAtrLength in a thread safe way
53f2798 
The field .cardAtrLength is used to know if a card is inserted and is
accessed from different threads.

We define it as _Atomic to have atomic accesses to the field and fix a
TSAN warning:
==================
WARNING: ThreadSanitizer: data race (pid=14987)
  Read of size 4 at 0x557bacd39cb0 by main thread:
    #0 RFWaitForReaderInit PCSC/src/readerfactory.c:1430:43 (pcscd+0xdda24) (BuildId: b43179fc4c418df0dad65d97dc7a0d9cc226d42f)
    #1 main PCSC/src/pcscdaemon.c:773:2 (pcscd+0xd87d4) (BuildId: b43179fc4c418df0dad65d97dc7a0d9cc226d42f)

  Previous write of size 8 at 0x557bacd39cb0 by thread T3:
    #0 EHStatusHandlerThread PCSC/src/eventhandler.c:314:40 (pcscd+0xd6a47) (BuildId: b43179fc4c418df0dad65d97dc7a0d9cc226d42f)

  Location is global 'readerStates' of size 2944 at 0x557bacd39c00 (pcscd+0x1496cb0)

  Thread T3 (tid=14992, running) created by main thread at:
    #0 pthread_create <null> (pcscd+0x53dfd) (BuildId: b43179fc4c418df0dad65d97dc7a0d9cc226d42f)
    #1 ThreadCreate PCSC/src/utils.c:184:8 (pcscd+0xe38cb) (BuildId: b43179fc4c418df0dad65d97dc7a0d9cc226d42f)
    #2 EHSpawnEventHandler PCSC/src/eventhandler.c:233:7 (pcscd+0xd6960) (BuildId: b43179fc4c418df0dad65d97dc7a0d9cc226d42f)
    #3 RFAddReader PCSC/src/readerfactory.c:397:8 (pcscd+0xdb632) (BuildId: b43179fc4c418df0dad65d97dc7a0d9cc226d42f)
    #4 HPAddDevice PCSC/src/hotplug_libudev.c:512:8 (pcscd+0xe3029) (BuildId: b43179fc4c418df0dad65d97dc7a0d9cc226d42f)
    #5 HPScanUSB PCSC/src/hotplug_libudev.c:579:3 (pcscd+0xe263d) (BuildId: b43179fc4c418df0dad65d97dc7a0d9cc226d42f)
    #6 HPRegisterForHotplugEvents PCSC/src/hotplug_libudev.c:761:2 (pcscd+0xe263d)
    #7 main PCSC/src/pcscdaemon.c:766:7 (pcscd+0xd87c7) (BuildId: b43179fc4c418df0dad65d97dc7a0d9cc226d42f)

SUMMARY: ThreadSanitizer: data race PCSC/src/readerfactory.c:1430:43 in RFWaitForReaderInit
==================

Thanks to Stefan Ehmann for the bug report.
LudovicRousseau added a commit that referenced this issue Nov 19, 2023
@LudovicRousseau
Fix a thread safe issue accessing contextsList
b64c8a9 
ContextsDeinitialize() was called by thread A in the middle of
list_delete() from thread B.
We already have a mutex to protect access to contextsList.

==================
WARNING: ThreadSanitizer: data race (pid=17581)
  Write of size 8 at 0x5606b8d11b60 by main thread:
    #0 list_clear PCSC/src/simclist.c:694:12 (pcscd+0xde66c) (BuildId: 807b741f905324f3ef4d96796ee2663eb8beddec)
    #1 list_destroy PCSC/src/simclist.c:313:5 (pcscd+0xde26c) (BuildId: 807b741f905324f3ef4d96796ee2663eb8beddec)
    #2 ContextsDeinitialize PCSC/src/winscard_svc.c:159:2 (pcscd+0xe4d13) (BuildId: 807b741f905324f3ef4d96796ee2663eb8beddec)
    #3 SVCServiceRunLoop PCSC/src/pcscdaemon.c:122:4 (pcscd+0xd9699) (BuildId: 807b741f905324f3ef4d96796ee2663eb8beddec)
    #4 main PCSC/src/pcscdaemon.c:799:2 (pcscd+0xd8930) (BuildId: 807b741f905324f3ef4d96796ee2663eb8beddec)

  Previous write of size 8 at 0x5606b8d11b60 by thread T6 (mutexes: write M0):
    #0 list_drop_elem PCSC/src/simclist.c:1457:36 (pcscd+0xdf63e) (BuildId: 807b741f905324f3ef4d96796ee2663eb8beddec)
    #1 list_delete_at PCSC/src/simclist.c:580:5 (pcscd+0xdf63e)
    #2 list_delete PCSC/src/simclist.c:563:6 (pcscd+0xdf1c7) (BuildId: 807b741f905324f3ef4d96796ee2663eb8beddec)
    #3 MSGCleanupClient PCSC/src/winscard_svc.c:1083:8 (pcscd+0xe9f6a) (BuildId: 807b741f905324f3ef4d96796ee2663eb8beddec)
    #4 ContextThread PCSC/src/winscard_svc.c:818:2 (pcscd+0xe98fd) (BuildId: 807b741f905324f3ef4d96796ee2663eb8beddec)

  As if synchronized via sleep:
    #0 nanosleep <null> (pcscd+0x515ed) (BuildId: 807b741f905324f3ef4d96796ee2663eb8beddec)
    #1 SYS_Sleep PCSC/src/sys_unix.c:69:9 (pcscd+0xdf8e9) (BuildId: 807b741f905324f3ef4d96796ee2663eb8beddec)
    #2 SVCServiceRunLoop PCSC/src/pcscdaemon.c:117:10 (pcscd+0xd968a) (BuildId: 807b741f905324f3ef4d96796ee2663eb8beddec)
    #3 main PCSC/src/pcscdaemon.c:799:2 (pcscd+0xd8930) (BuildId: 807b741f905324f3ef4d96796ee2663eb8beddec)

  Location is global 'contextsList' of size 120 at 0x5606b8d11b50 (pcscd+0x1497b60)

  Mutex M0 (0x5606b8d11bc8) created at:
    #0 pthread_mutex_init <null> (pcscd+0x555cf) (BuildId: 807b741f905324f3ef4d96796ee2663eb8beddec)
    #1 ContextsInitialize PCSC/src/winscard_svc.c:144:8 (pcscd+0xe4be5) (BuildId: 807b741f905324f3ef4d96796ee2663eb8beddec)
    #2 main PCSC/src/pcscdaemon.c:737:7 (pcscd+0xd8780) (BuildId: 807b741f905324f3ef4d96796ee2663eb8beddec)

  Thread T6 (tid=17591, finished) created by main thread at:
    #0 pthread_create <null> (pcscd+0x53dfd) (BuildId: 807b741f905324f3ef4d96796ee2663eb8beddec)
    #1 ThreadCreate PCSC/src/utils.c:184:8 (pcscd+0xe399b) (BuildId: 807b741f905324f3ef4d96796ee2663eb8beddec)
    #2 CreateContextThread PCSC/src/winscard_svc.c:237:7 (pcscd+0xd936e) (BuildId: 807b741f905324f3ef4d96796ee2663eb8beddec)
    #3 SVCServiceRunLoop PCSC/src/pcscdaemon.c:131:9 (pcscd+0xd936e)
    #4 main PCSC/src/pcscdaemon.c:799:2 (pcscd+0xd8930) (BuildId: 807b741f905324f3ef4d96796ee2663eb8beddec)
    #5 main PCSC/src/pcscdaemon.c:799:2 (pcscd+0xd8930) (BuildId: 807b741f905324f3ef4d96796ee2663eb8beddec)

SUMMARY: ThreadSanitizer: data race PCSC/src/simclist.c:694:12 in list_clear
==================
LudovicRousseau added a commit that referenced this issue Nov 19, 2023
@LudovicRousseau
Fix data race issue accessing a logging variable
b680db2 
The struct timeval used in log_line() can't be accessed in a atomic way
so we should protect it using a mutex.

==================
WARNING: ThreadSanitizer: data race (pid=5391)
  Read of size 8 at 0x55b3bba7b950 by thread T3 (mutexes: write M17):
    #0 log_line /PCSC-debug/src/debuglog.c:217 (pcscd+0x9d7e)
    #1 log_msg /PCSC-debug/src/debuglog.c:148 (pcscd+0x9a85)
    #2 IFDHPowerICC <null> (libccid.so+0x8a54)
    #3 EHStatusHandlerThread /PCSC-debug/src/eventhandler.c:395 (pcscd+0xbafe)

  Previous write of size 8 at 0x55b3bba7b950 by main thread:
    #0 log_line /PCSC-debug/src/debuglog.c:232 (pcscd+0x9e77)
    #1 log_msg /PCSC-debug/src/debuglog.c:148 (pcscd+0x9a85)
    #2 get_driver /PCSC-debug/src/hotplug_libudev.c:298 (pcscd+0x1f75d)
    #3 HPAddDevice /PCSC-debug/src/hotplug_libudev.c:394 (pcscd+0x1ff32)
    #4 HPScanUSB /PCSC-debug/src/hotplug_libudev.c:579 (pcscd+0x209db)
    #5 HPRegisterForHotplugEvents /PCSC-debug/src/hotplug_libudev.c:761
(pcscd+0x21255)
    #6 main /PCSC-debug/src/pcscdaemon.c:766 (pcscd+0xe6fa)

  Location is global 'last_time.3' of size 16 at 0x55b3bba7b950
(pcscd+0x35950)

  Mutex M17 (0x7b0c000014d0) created at:
    #0 pthread_mutex_init ../../../../src/libsanitizer/tsan/
tsan_interceptors_posix.cpp:1295 (libtsan.so.2+0x50468)
    #1 RFAddReader /PCSC-debug/src/readerfactory.c:355 (pcscd+0x10b8c)
    #2 HPAddDevice /PCSC-debug/src/hotplug_libudev.c:512 (pcscd+0x205b0)
    #3 HPScanUSB /PCSC-debug/src/hotplug_libudev.c:579 (pcscd+0x209db)
    #4 HPRegisterForHotplugEvents /PCSC-debug/src/hotplug_libudev.c:761
(pcscd+0x21255)
    #5 main /PCSC-debug/src/pcscdaemon.c:766 (pcscd+0xe6fa)

  Thread T3 (tid=5395, running) created by main thread at:
    #0 pthread_create ../../../../src/libsanitizer/tsan/
tsan_interceptors_posix.cpp:1001 (libtsan.so.2+0x5e686)
    #1 ThreadCreate /PCSC-debug/src/utils.c:184 (pcscd+0x21755)
    #2 EHSpawnEventHandler /PCSC-debug/src/eventhandler.c:233 (pcscd+0xb2d9)
    #3 RFAddReader /PCSC-debug/src/readerfactory.c:397 (pcscd+0x10f1a)
    #4 HPAddDevice /PCSC-debug/src/hotplug_libudev.c:512 (pcscd+0x205b0)
    #5 HPScanUSB /PCSC-debug/src/hotplug_libudev.c:579 (pcscd+0x209db)
    #6 HPRegisterForHotplugEvents /PCSC-debug/src/hotplug_libudev.c:761
(pcscd+0x21255)
    #7 main /PCSC-debug/src/pcscdaemon.c:766 (pcscd+0xe6fa)

SUMMARY: ThreadSanitizer: data race /PCSC-debug/src/debuglog.c:217 in log_line
==================

Thanks to Stefan Ehmann for the bug report and patch.
LudovicRousseau added a commit that referenced this issue Nov 19, 2023
@LudovicRousseau
Fix data race on reader disconnect
07ce6b4 
The field .vHandle is used to check the validity of the reader.

It is accessed in write mode in RFUnloadReader() from a thread A while
it is also accessed in read mode in RFWaitForReaderInit() from thread B.

==================
WARNING: ThreadSanitizer: data race (pid=23997)
  Write of size 8 at 0x7b4c000002d8 by thread T5:
    #0 RFUnloadReader PCSC/src/readerfactory.c:1005:20 (pcscd+0xda017) (BuildId: db0b27e1c3b409153327b14d9e501205ed34fb6e)
    #1 RFUnInitializeReader PCSC/src/readerfactory.c:1151:8 (pcscd+0xda017)
    #2 removeReader PCSC/src/readerfactory.c:645:2 (pcscd+0xda017)
    #3 _UnrefReader PCSC/src/readerfactory.c:120:3 (pcscd+0xda017)
    #4 RFRemoveReader PCSC/src/readerfactory.c:624:5 (pcscd+0xdd11b) (BuildId: db0b27e1c3b409153327b14d9e501205ed34fb6e)
    #5 RFRemoveReader PCSC/src/readerfactory.c:624:5 (pcscd+0xdd11b) (BuildId: db0b27e1c3b409153327b14d9e501205ed34fb6e)
    #6 HPRemoveDevice PCSC/src/hotplug_libudev.c:348:4 (pcscd+0xe35af) (BuildId: db0b27e1c3b409153327b14d9e501205ed34fb6e)
    #7 HPEstablishUSBNotifications PCSC/src/hotplug_libudev.c:640:6 (pcscd+0xe35af)

  Previous read of size 8 at 0x7b4c000002d8 by main thread:
    #0 RFWaitForReaderInit PCSC/src/readerfactory.c:1426:29 (pcscd+0xddabe) (BuildId: db0b27e1c3b409153327b14d9e501205ed34fb6e)
    #1 main PCSC/src/pcscdaemon.c:773:2 (pcscd+0xd8864) (BuildId: db0b27e1c3b409153327b14d9e501205ed34fb6e)

  Location is heap block of size 400 at 0x7b4c000001c0 allocated by main thread:
    #0 malloc <null> (pcscd+0x52691) (BuildId: db0b27e1c3b409153327b14d9e501205ed34fb6e)
    #1 RFAllocateReaderSpace PCSC/src/readerfactory.c:135:25 (pcscd+0xda3b9) (BuildId: db0b27e1c3b409153327b14d9e501205ed34fb6e)
    #2 main PCSC/src/pcscdaemon.c:643:7 (pcscd+0xd85a5) (BuildId: db0b27e1c3b409153327b14d9e501205ed34fb6e)

  Thread T5 (tid=24004, running) created by main thread at:
    #0 pthread_create <null> (pcscd+0x53dfd) (BuildId: db0b27e1c3b409153327b14d9e501205ed34fb6e)
    #1 ThreadCreate PCSC/src/utils.c:184:8 (pcscd+0xe39bb) (BuildId: db0b27e1c3b409153327b14d9e501205ed34fb6e)
    #2 HPRegisterForHotplugEvents PCSC/src/hotplug_libudev.c:763:6 (pcscd+0xe2768) (BuildId: db0b27e1c3b409153327b14d9e501205ed34fb6e)
    #3 main PCSC/src/pcscdaemon.c:766:7 (pcscd+0xd8857) (BuildId: db0b27e1c3b409153327b14d9e501205ed34fb6e)

SUMMARY: ThreadSanitizer: data race PCSC/src/readerfactory.c:1005:20 in RFUnloadReader
==================
LudovicRousseau added a commit that referenced this issue Nov 19, 2023
@LudovicRousseau
Fix an issue on pcscd exit
8cbab7b 
When pcscd exits we must first terminate any client thread on the
server side before closing the reader threads.
This is to prevent a client thread to access a now deactivated reader.

The error was:
^C00250854 [140433941325504] pcscdaemon.c:192:signal_thread() Received signal: 2
00000036 [140433941325504] pcscdaemon.c:226:signal_thread() Preparing for suicide
[...readers are stopped here...]
00000042 [140433995138368] pcscdaemon.c:809:at_exit() cleaning /run/pcscd
[...but we get a new request from a client...]
00000016 [140433906050752] winscard_svc.c:384:ContextThread() Received command: CMD_WAIT_READER_STATE_CHANGE from client 12
==================
WARNING: ThreadSanitizer: use of an invalid mutex (e.g. uninitialized or destroyed) (pid=62372)
    #0 pthread_mutex_lock <null> (pcscd+0x71ada) (BuildId: 1bcd3f8a880d8c656c6e6bbe77b504b573d68914)
    #1 EHRegisterClientForEvent PCSC/src/eventhandler.c:68:8 (pcscd+0xe5b2a) (BuildId: 1bcd3f8a880d8c656c6e6bbe77b504b573d68914)
    #2 ContextThread PCSC/src/winscard_svc.c:446:5 (pcscd+0xe5b2a)
    #3 __tsan_thread_start_func <null> (pcscd+0x53d66) (BuildId: 1bcd3f8a880d8c656c6e6bbe77b504b573d68914)

  Location is global 'ClientsWaitingForEvent_lock' of size 40 at 0x556bd69d67c8 (pcscd+0x14977c8)

  Mutex M0 (0x556bd69d67c8) created at:
    [failed to restore the stack]

SUMMARY: ThreadSanitizer: use of an invalid mutex (e.g. uninitialized or destroyed) (PCSC/src/pcscd+0x71ada) (BuildId: 1bcd3f8a880d8c656c6e6bbe77b504b573d68914) in __interceptor_pthread_mutex_lock
==================
==================
WARNING: ThreadSanitizer: heap-use-after-free (pid=62372)
  Read of size 8 at 0x7b0c00000060 by thread T5:
    #0 list_insert_at PCSC/src/simclist.c:503:16 (pcscd+0xdea60) (BuildId: 1bcd3f8a880d8c656c6e6bbe77b504b573d68914)
    #1 list_append PCSC/src/simclist.c:397:12 (pcscd+0xdea60)
    #2 EHRegisterClientForEvent PCSC/src/eventhandler.c:70:8 (pcscd+0xe5b39) (BuildId: 1bcd3f8a880d8c656c6e6bbe77b504b573d68914)
    #3 ContextThread PCSC/src/winscard_svc.c:446:5 (pcscd+0xe5b39)
    #4 EHRegisterClientForEvent PCSC/src/eventhandler.c:70:8 (pcscd+0xe5b39) (BuildId: 1bcd3f8a880d8c656c6e6bbe77b504b573d68914)
    #5 ContextThread PCSC/src/winscard_svc.c:446:5 (pcscd+0xe5b39)
    #6 __tsan_thread_start_func <null> (pcscd+0x53d66) (BuildId: 1bcd3f8a880d8c656c6e6bbe77b504b573d68914)

  Previous write of size 8 at 0x7b0c00000060 by main thread:
    #0 free <null> (pcscd+0x52c84) (BuildId: 1bcd3f8a880d8c656c6e6bbe77b504b573d68914)
    #1 list_destroy PCSC/src/simclist.c:317:5 (pcscd+0xde590) (BuildId: 1bcd3f8a880d8c656c6e6bbe77b504b573d68914)
    #2 EHDeinitializeEventStructures PCSC/src/eventhandler.c:152:2 (pcscd+0xd6866) (BuildId: 1bcd3f8a880d8c656c6e6bbe77b504b573d68914)
    #3 SVCServiceRunLoop PCSC/src/pcscdaemon.c:124:4 (pcscd+0xd9649) (BuildId: 1bcd3f8a880d8c656c6e6bbe77b504b573d68914)
    #4 main PCSC/src/pcscdaemon.c:801:2 (pcscd+0xd88e0) (BuildId: 1bcd3f8a880d8c656c6e6bbe77b504b573d68914)

  Thread T5 (tid=62379, running) created by main thread at:
    #0 pthread_create <null> (pcscd+0x53dfd) (BuildId: 1bcd3f8a880d8c656c6e6bbe77b504b573d68914)
    #1 ThreadCreate PCSC/src/utils.c:184:8 (pcscd+0xe3c7b) (BuildId: 1bcd3f8a880d8c656c6e6bbe77b504b573d68914)
    #2 CreateContextThread PCSC/src/winscard_svc.c:258:7 (pcscd+0xd931e) (BuildId: 1bcd3f8a880d8c656c6e6bbe77b504b573d68914)
    #3 SVCServiceRunLoop PCSC/src/pcscdaemon.c:133:9 (pcscd+0xd931e)
    #4 main PCSC/src/pcscdaemon.c:801:2 (pcscd+0xd88e0) (BuildId: 1bcd3f8a880d8c656c6e6bbe77b504b573d68914)
    #5 main PCSC/src/pcscdaemon.c:801:2 (pcscd+0xd88e0) (BuildId: 1bcd3f8a880d8c656c6e6bbe77b504b573d68914)

SUMMARY: ThreadSanitizer: heap-use-after-free PCSC/src/simclist.c:503:16 in list_insert_at
==================
etc..
LudovicRousseau added a commit that referenced this issue Nov 19, 2023
@LudovicRousseau
Access readerSharing in a thread safe way
41cd9ec 
The field .readerSharing can be used from different theads at the same
time.

We define it as _Atomic to have atomic accesses to the field and fix a
TSAN warning:
==================
WARNING: ThreadSanitizer: data race (pid=63123)
  Write of size 4 at 0x5575884d8cb8 by thread T3:
    #0 EHStatusHandlerThread PCSC/src/eventhandler.c:449:41 (pcscd+0xd6f12) (BuildId: b2f519c8807f458b6282d631fe17086d4f6da420)

  Previous write of size 4 at 0x5575884d8cb8 by thread T8:
    #0 SCardDisconnect PCSC/src/winscard.c:1034:39 (pcscd+0xe4779) (BuildId: b2f519c8807f458b6282d631fe17086d4f6da420)
    #1 ContextThread PCSC/src/winscard_svc.c:575:16 (pcscd+0xe6507) (BuildId: b2f519c8807f458b6282d631fe17086d4f6da420)

  As if synchronized via sleep:
    #0 nanosleep <null> (pcscd+0x515ed) (BuildId: b2f519c8807f458b6282d631fe17086d4f6da420)
    #1 SYS_USleep PCSC/src/sys_unix.c:87:9 (pcscd+0xd6fca) (BuildId: b2f519c8807f458b6282d631fe17086d4f6da420)
    #2 EHStatusHandlerThread PCSC/src/eventhandler.c (pcscd+0xd6fca)
    #3 __tsan_thread_start_func <null> (pcscd+0x53d66) (BuildId: b2f519c8807f458b6282d631fe17086d4f6da420)

  Location is global 'readerStates' of size 2944 at 0x5575884d8c30 (pcscd+0x1497cb8)

  Thread T3 (tid=63127, running) created by main thread at:
    #0 pthread_create <null> (pcscd+0x53dfd) (BuildId: b2f519c8807f458b6282d631fe17086d4f6da420)
    #1 ThreadCreate PCSC/src/utils.c:184:8 (pcscd+0xe3cab) (BuildId: b2f519c8807f458b6282d631fe17086d4f6da420)
    #2 EHSpawnEventHandler PCSC/src/eventhandler.c:233:7 (pcscd+0xd6840) (BuildId: b2f519c8807f458b6282d631fe17086d4f6da420)
    #3 RFAddReader PCSC/src/readerfactory.c:397:8 (pcscd+0xdb6dd) (BuildId: b2f519c8807f458b6282d631fe17086d4f6da420)
    #4 HPAddDevice PCSC/src/hotplug_libudev.c:512:8 (pcscd+0xe3409) (BuildId: b2f519c8807f458b6282d631fe17086d4f6da420)
    #5 HPScanUSB PCSC/src/hotplug_libudev.c:579:3 (pcscd+0xe2a1d) (BuildId: b2f519c8807f458b6282d631fe17086d4f6da420)
    #6 HPRegisterForHotplugEvents PCSC/src/hotplug_libudev.c:761:2 (pcscd+0xe2a1d)
    #7 main PCSC/src/pcscdaemon.c:768:7 (pcscd+0xd8717) (BuildId: b2f519c8807f458b6282d631fe17086d4f6da420)

  Thread T8 (tid=63221, finished) created by main thread at:
    #0 pthread_create <null> (pcscd+0x53dfd) (BuildId: b2f519c8807f458b6282d631fe17086d4f6da420)
    #1 ThreadCreate PCSC/src/utils.c:184:8 (pcscd+0xe3cab) (BuildId: b2f519c8807f458b6282d631fe17086d4f6da420)
    #2 CreateContextThread PCSC/src/winscard_svc.c:256:7 (pcscd+0xd924e) (BuildId: b2f519c8807f458b6282d631fe17086d4f6da420)
    #3 SVCServiceRunLoop PCSC/src/pcscdaemon.c:133:9 (pcscd+0xd924e)
    #4 main PCSC/src/pcscdaemon.c:801:2 (pcscd+0xd8810) (BuildId: b2f519c8807f458b6282d631fe17086d4f6da420)
    #5 main PCSC/src/pcscdaemon.c:801:2 (pcscd+0xd8810) (BuildId: b2f519c8807f458b6282d631fe17086d4f6da420)

SUMMARY: ThreadSanitizer: data race PCSC/src/eventhandler.c:449:41 in EHStatusHandlerThread
==================
LudovicRousseau added a commit that referenced this issue Nov 19, 2023
@LudovicRousseau
Access LockCount in a thread safe way
f0213d8 
The field .LockCount can be used from different theads at the same
time.

We define it as _Atomic to have atomic accesses to the field and fix a
TSAN warning:
==================
WARNING: ThreadSanitizer: data race (pid=64069)
  Write of size 4 at 0x7b4c00000138 by thread T6 (mutexes: write M0):
    #0 RFUnlockAllSharing PCSC/src/readerfactory.c:1080:23 (pcscd+0xe3f15) (BuildId: ca24a31c13ced4613b52730b820229170aba90d6)
    #1 SCardDisconnect PCSC/src/winscard.c:863:7 (pcscd+0xe3f15)
    #2 ContextThread PCSC/src/winscard_svc.c:575:16 (pcscd+0xe64f7) (BuildId: ca24a31c13ced4613b52730b820229170aba90d6)
    #3 ContextThread PCSC/src/winscard_svc.c:575:16 (pcscd+0xe64f7) (BuildId: ca24a31c13ced4613b52730b820229170aba90d6)

  Previous write of size 4 at 0x7b4c00000138 by thread T3:
    #0 RFSetReaderEventState PCSC/src/readerfactory.c:1304:23 (pcscd+0xdd8f2) (BuildId: ca24a31c13ced4613b52730b820229170aba90d6)
    #1 EHStatusHandlerThread PCSC/src/eventhandler.c:362:11 (pcscd+0xd6c9c) (BuildId: ca24a31c13ced4613b52730b820229170aba90d6)

  Location is heap block of size 400 at 0x7b4c00000000 allocated by main thread:
    #0 malloc <null> (pcscd+0x52691) (BuildId: ca24a31c13ced4613b52730b820229170aba90d6)
    #1 RFAllocateReaderSpace PCSC/src/readerfactory.c:135:25 (pcscd+0xda2e9) (BuildId: ca24a31c13ced4613b52730b820229170aba90d6)
    #2 main PCSC/src/pcscdaemon.c:645:7 (pcscd+0xd8465) (BuildId: ca24a31c13ced4613b52730b820229170aba90d6)

  Mutex M0 (0x55dc20366908) created at:
    #0 pthread_mutex_lock <null> (pcscd+0x71ada) (BuildId: ca24a31c13ced4613b52730b820229170aba90d6)
    #1 RFUnlockAllSharing PCSC/src/readerfactory.c:1076:8 (pcscd+0xe3ecf) (BuildId: ca24a31c13ced4613b52730b820229170aba90d6)
    #2 SCardDisconnect PCSC/src/winscard.c:863:7 (pcscd+0xe3ecf)
    #3 ContextThread PCSC/src/winscard_svc.c:575:16 (pcscd+0xe64f7) (BuildId: ca24a31c13ced4613b52730b820229170aba90d6)
    #4 ContextThread PCSC/src/winscard_svc.c:575:16 (pcscd+0xe64f7) (BuildId: ca24a31c13ced4613b52730b820229170aba90d6)

  Thread T6 (tid=64077, running) created by main thread at:
    #0 pthread_create <null> (pcscd+0x53dfd) (BuildId: ca24a31c13ced4613b52730b820229170aba90d6)
    #1 ThreadCreate PCSC/src/utils.c:184:8 (pcscd+0xe3c9b) (BuildId: ca24a31c13ced4613b52730b820229170aba90d6)
    #2 CreateContextThread PCSC/src/winscard_svc.c:256:7 (pcscd+0xd924e) (BuildId: ca24a31c13ced4613b52730b820229170aba90d6)
    #3 SVCServiceRunLoop PCSC/src/pcscdaemon.c:133:9 (pcscd+0xd924e)
    #4 main PCSC/src/pcscdaemon.c:801:2 (pcscd+0xd8810) (BuildId: ca24a31c13ced4613b52730b820229170aba90d6)
    #5 main PCSC/src/pcscdaemon.c:801:2 (pcscd+0xd8810) (BuildId: ca24a31c13ced4613b52730b820229170aba90d6)

  Thread T3 (tid=64073, running) created by main thread at:
    #0 pthread_create <null> (pcscd+0x53dfd) (BuildId: ca24a31c13ced4613b52730b820229170aba90d6)
    #1 ThreadCreate PCSC/src/utils.c:184:8 (pcscd+0xe3c9b) (BuildId: ca24a31c13ced4613b52730b820229170aba90d6)
    #2 EHSpawnEventHandler PCSC/src/eventhandler.c:233:7 (pcscd+0xd6840) (BuildId: ca24a31c13ced4613b52730b820229170aba90d6)
    #3 RFAddReader PCSC/src/readerfactory.c:397:8 (pcscd+0xdb6cd) (BuildId: ca24a31c13ced4613b52730b820229170aba90d6)
    #4 HPAddDevice PCSC/src/hotplug_libudev.c:512:8 (pcscd+0xe33f9) (BuildId: ca24a31c13ced4613b52730b820229170aba90d6)
    #5 HPScanUSB PCSC/src/hotplug_libudev.c:579:3 (pcscd+0xe2a0d) (BuildId: ca24a31c13ced4613b52730b820229170aba90d6)
    #6 HPRegisterForHotplugEvents PCSC/src/hotplug_libudev.c:761:2 (pcscd+0xe2a0d)
    #7 main PCSC/src/pcscdaemon.c:768:7 (pcscd+0xd8717) (BuildId: ca24a31c13ced4613b52730b820229170aba90d6)

SUMMARY: ThreadSanitizer: data race PCSC/src/readerfactory.c:1080:23 in RFUnlockAllSharing
==================
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@LudovicRousseau @shearl @Jean-Baptiste-Lasselle