There is no valid case for supporting duplicate pseudoflavor registrations. Currently the silent acceptance of such registrations is hiding a bug. The rpcsec_gss_krb5 module registers 2 flavours but does not unregister them, so if you load, unload, reload the module, it will happily continue to use the old registration which now has pointers to the memory were the module was originally loaded. This could lead to unexpected results. So disallow duplicate registrations. Link: https://bugzilla.kernel.org/show_bug.cgi?id=206651 Cc: stable@xxxxxxxxxxxxxxx Signed-off-by: NeilBrown <neilb@xxxxxxx> --- net/sunrpc/auth_gss/svcauth_gss.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/net/sunrpc/auth_gss/svcauth_gss.c b/net/sunrpc/auth_gss/svcauth_gss.c index 50d93c49ef1a..4aaaad794edb 100644 --- a/net/sunrpc/auth_gss/svcauth_gss.c +++ b/net/sunrpc/auth_gss/svcauth_gss.c @@ -826,9 +826,12 @@ svcauth_gss_register_pseudoflavor(u32 pseudoflavor, char * name) new->h.flavour = &svcauthops_gss; new->pseudoflavor = pseudoflavor; - stat = 0; test = auth_domain_lookup(name, &new->h); if (test != &new->h) { /* Duplicate registration */ + printk(KERN_WARNING + "SUNRPC:svcauth_gss: duplicate pseudo flavour registration of %s\n", + name); + stat = -EALREADY; auth_domain_put(test); kfree(new->h.name); goto out_free_dom;
