You have been subscribed to a public bug by Nicolas Bock (nicolasbock): [Impact]
Bionic's OpenSSL 1.1.1 package (https://launchpad.net/ubuntu/bionic/+source/openssl) is the only version of openssl 1.1.1 on any distro that we've encountered that does not have support for the OPENSSL_NO_ATEXIT functionality from 1.1.1b (openssl/openssl@c2b3db2). The threading model in .NET has the possibility that background threads are still running when exit() is called, which can cause SIGSEGV if a background thread interacts with OpenSSL after/while it has unloaded. For that reason, we always initialize OpenSSL 1.1.1 with the OPENSSL_NO_ATEXIT flag (which, of all the distros we run on only has no effect on Bionic). We feel that the stability of applications on Ubuntu 18.04 would be improved if the functionality of OPENSSL_NO_ATEXIT was merged into the bionic openssl 1.1.1 package, even if the constant isn't published into the header for the dev package. Context: https://github.com/dotnet/runtime/issues/48411#issuecomment-1178405101 [Test Plan] The described behavior can be reproduced by passing the OPENSSL_NO_ATEXIT to the OPENSSL_init_ssl() call. The application will terminate with a SEGFAULT. More concretely, a minimal reproducer is: #include <stdio.h> #include <openssl/err.h> #include <openssl/ssl.h> #ifndef OPENSSL_INIT_NO_ATEXIT #define OPENSSL_INIT_NO_ATEXIT 0x00080000L #endif static void print_error_string() { printf("print_error_string:\n"); printf("ERR_reason_error_string(0) => %s\n", ERR_reason_error_string(0)); } int main(int argc, char* argv[]) { // register this handler first, so it runs last. atexit(print_error_string); OPENSSL_init_ssl( OPENSSL_INIT_ADD_ALL_CIPHERS | OPENSSL_INIT_ADD_ALL_DIGESTS | OPENSSL_INIT_LOAD_CONFIG | OPENSSL_INIT_NO_ATEXIT | OPENSSL_INIT_LOAD_CRYPTO_STRINGS | OPENSSL_INIT_LOAD_SSL_STRINGS, NULL); print_error_string(); return 0; } Building $ sudo apt install libssl-dev $ gcc test.c -lssl -lcrypto $ ./a.out print_error_string: ERR_reason_error_string(0) => (null) print_error_string: Segmentation fault (core dumped) [Where problems could occur] The patches adds an option to the OPENSSL_init_crypto() function to disable the default behavior of calling of a cleanup function on application exit. The patch also includes a few bug fixes around various initializations that were supposed to happen once when running threaded but were not. These changes have the potential for regressions and it is conceivable that they lead to incorrect behavior. However, I have also backported and included all new testing functions in the hope that the changed behavior will get appropriate testing. ** Affects: openssl (Ubuntu) Importance: Undecided Status: New ** Affects: openssl (Ubuntu Bionic) Importance: Undecided Status: New -- dotnet build intermittently crashes with segfault on Ubuntu 18.04 https://bugs.launchpad.net/bugs/1983100 You received this bug notification because you are a member of SE SRU ("STS") Sponsors, which is subscribed to the bug report. -- Mailing list: https://launchpad.net/~sts-sponsors Post to : sts-sponsors@lists.launchpad.net Unsubscribe : https://launchpad.net/~sts-sponsors More help : https://help.launchpad.net/ListHelp
