using CURL_LOCK_DATA_COOKIE to share cookies causes crashes

[afengsoft]

I did this

Since version 8.11.1, starting from 8.12, using CURL_LOCK_DATA_COOKIE to share cookies causes crashes. There were no issues before 8.11.1. Even after setting the lock, it still crashes the same way.

        curl_share_setopt(g_share_handle, CURLSHOPT_SHARE, CURL_LOCK_DATA_COOKIE);
        curl_share_setopt(g_share_handle, CURLSHOPT_SHARE, CURL_LOCK_DATA_DNS);
        curl_share_setopt(g_share_handle, CURLSHOPT_SHARE, CURL_LOCK_DATA_SSL_SESSION);

        curl_share_setopt(g_share_handle, CURLSHOPT_LOCKFUNC, (LOCK)lockFunc);
        curl_share_setopt(g_share_handle, CURLSHOPT_UNLOCKFUNC, (UNLOCK)unlockFunc);
        curl_share_setopt(g_share_handle, CURLSHOPT_USERDATA, &g_curlMutex);

I expected the following

No response

curl/libcurl version

curl 8.14.1

operating system

windows11

[afengsoft]

It crashes during multithreaded usage.

[dfandrich]

Can you be more specific about those versions? Neither 8.20 nor 8.41.1 are valid curl versions.

[afengsoft]

Sorry, I wrote the wrong version number. Versions 7.88-8.11.1 are normal, but versions 8.12.0 to 8.14.1 will crash during multi-threaded usage.

[afengsoft]

This page mentions that,"It is not supported to share cookies between multiple concurrent threads."
https://curl.se/libcurl/c/CURLSHOPT_SHARE.html

But this page only mentions locking—it doesn’t say multi-threading is prohibited. Moreover, it worked fine in version 7.88. Last night, I tested every version from the latest (8.14.1) down to 8.11.1 and found that 8.11.1 still works properly. However, all newer versions after that crash.
https://everything.curl.dev/helpers/sharing.html?highlight=CURL_LOCK_DATA_COOKIE#sharing-between-easy-handles

[bagder]

First, says exactly this:

It is not supported to share cookies between multiple concurrent threads.

So if that is what you do, then you should not be surprised.

Moreover, it worked fine in version 7.88

That just means you were lucky back then and you are not lucky anymore.

[bagder]

So, while this is kind of a bug it is a document limitation for now. I don't know of anyone working on fixing it, but we would of course greatly appreciate such work. Until then, this is (not) working as documented.