Hello, I was pulling the latest autofs from Debian into Ubuntu and, due to a mistake of mine, I dropped a line in d/rules that was _removing_ the -Wl,-Bsymbolic-functions flag from LDFLAGS set by Ubuntu. The build proceeded as normal, packages installed, and I started getting segfaults all over the place. This has happened before: https://bugs.launchpad.net/ubuntu/+source/autofs/+bug/1470687: Not working properly with compile options "-symbolic-functions" https://bugs.launchpad.net/ubuntu/+source/autofs/+bug/1472115: autofs start fails: segfault at 0 ip .... https://bugs.launchpad.net/ubuntu/+source/autofs/+bug/1503034: Autofs 5.1.1-1ubuntu2 crashes with segfault on startup For the lookup_ldap specific case, just dropping the linker flag from Ubuntu's LDFLAGS wasn't enough, because it leaks back in via $(krb5-config --libs), so a patch (attached) was contributed by Malcolm Scott (https://bugs.launchpad.net/ubuntu/+source/autofs/+bug/1503034/comments/7). The patch still applies to current master, but with some offset. Would there be interest from upstream in adopting this patch, even though there is no crash on a default upstream build? If this makes sense, other modules could follow the same path. I also asked ubuntu-devel for the reasoning for -Wl,-Bsymbolic-functions and why Debian isn't using it: https://lists.ubuntu.com/archives/ubuntu-devel/2018-June/040369.html. It looks like it's one of those things that just never converged between the two distros. Thanks!
Description: Fix segfault in lookup_ldap initialisation lib/defaults.c doesn't initialise the config cache before lookup_ldap attempts to read from it. . <andreas> lookup_ldap is the only module that is still built and linked using -Bsymbolic-functions. d/rules tries to strip that option out of LDFLAGS, but it leaks back in via $(krb5-config --libs) when lookup_ldap is built. Author: Malcolm Scott <debianpkg@xxxxxxxxxxx> Bug-Ubuntu: https://bugs.launchpad.net/bugs/1503034 Index: autofs-5.1.1/modules/lookup_ldap.c =================================================================== --- autofs-5.1.1.orig/modules/lookup_ldap.c +++ autofs-5.1.1/modules/lookup_ldap.c @@ -1665,6 +1665,11 @@ int lookup_init(const char *mapfmt, int ctxt->check_defaults = 1; } + if (!defaults_read_config(0)) { + free_context(ctxt); + return 1; + } + ctxt->timeout = defaults_get_ldap_timeout(); ctxt->network_timeout = defaults_get_ldap_network_timeout();
