From: NeilBrown The server sunrpc code should take a reference on the relevant module before calling any authentication code. Also, it looks to me like the table of authops needs some locking. Finally, gss_svc_init wasn't checking the status of svc_auth_register, and gss_svc_shutdown wasn't calling svc_auth_unregister. From: "J. Bruce Fields" Signed-off-by: Neil Brown --- 25-akpm/include/linux/sunrpc/svcauth.h | 1 + 25-akpm/net/sunrpc/auth_gss/svcauth_gss.c | 12 ++++++++---- 25-akpm/net/sunrpc/svcauth.c | 25 +++++++++++++++++++------ 25-akpm/net/sunrpc/svcauth_unix.c | 3 +++ 4 files changed, 31 insertions(+), 10 deletions(-) diff -puN include/linux/sunrpc/svcauth.h~knfsd-5-of-11-gss_svc_module_refpatch include/linux/sunrpc/svcauth.h --- 25/include/linux/sunrpc/svcauth.h~knfsd-5-of-11-gss_svc_module_refpatch 2004-05-28 00:10:36.967127552 -0700 +++ 25-akpm/include/linux/sunrpc/svcauth.h 2004-05-28 00:10:36.974126488 -0700 @@ -87,6 +87,7 @@ struct auth_domain { */ struct auth_ops { char * name; + struct module *owner; int flavour; int (*accept)(struct svc_rqst *rq, u32 *authp); int (*release)(struct svc_rqst *rq); diff -puN net/sunrpc/auth_gss/svcauth_gss.c~knfsd-5-of-11-gss_svc_module_refpatch net/sunrpc/auth_gss/svcauth_gss.c --- 25/net/sunrpc/auth_gss/svcauth_gss.c~knfsd-5-of-11-gss_svc_module_refpatch 2004-05-28 00:10:36.968127400 -0700 +++ 25-akpm/net/sunrpc/auth_gss/svcauth_gss.c 2004-05-28 00:10:36.975126336 -0700 @@ -1045,6 +1045,7 @@ svcauth_gss_domain_release(struct auth_d struct auth_ops svcauthops_gss = { .name = "rpcsec_gss", + .owner = THIS_MODULE, .flavour = RPC_AUTH_GSS, .accept = svcauth_gss_accept, .release = svcauth_gss_release, @@ -1054,10 +1055,12 @@ struct auth_ops svcauthops_gss = { int gss_svc_init(void) { - cache_register(&rsc_cache); - cache_register(&rsi_cache); - svc_auth_register(RPC_AUTH_GSS, &svcauthops_gss); - return 0; + int rv = svc_auth_register(RPC_AUTH_GSS, &svcauthops_gss); + if (rv == 0) { + cache_register(&rsc_cache); + cache_register(&rsi_cache); + } + return rv; } void @@ -1065,4 +1068,5 @@ gss_svc_shutdown(void) { cache_unregister(&rsc_cache); cache_unregister(&rsi_cache); + svc_auth_unregister(RPC_AUTH_GSS); } diff -puN net/sunrpc/svcauth.c~knfsd-5-of-11-gss_svc_module_refpatch net/sunrpc/svcauth.c --- 25/net/sunrpc/svcauth.c~knfsd-5-of-11-gss_svc_module_refpatch 2004-05-28 00:10:36.969127248 -0700 +++ 25-akpm/net/sunrpc/svcauth.c 2004-05-28 00:10:36.976126184 -0700 @@ -11,6 +11,7 @@ #include #include +#include #include #include #include @@ -27,6 +28,7 @@ extern struct auth_ops svcauth_null; extern struct auth_ops svcauth_unix; +static spinlock_t authtab_lock = SPIN_LOCK_UNLOCKED; static struct auth_ops *authtab[RPC_AUTH_MAXFLAVOR] = { [0] = &svcauth_null, [1] = &svcauth_unix, @@ -43,10 +45,15 @@ svc_authenticate(struct svc_rqst *rqstp, flavor = ntohl(svc_getu32(&rqstp->rq_arg.head[0])); dprintk("svc: svc_authenticate (%d)\n", flavor); - if (flavor >= RPC_AUTH_MAXFLAVOR || !(aops = authtab[flavor])) { + + spin_lock(&authtab_lock); + if (flavor >= RPC_AUTH_MAXFLAVOR || !(aops = authtab[flavor]) + || !try_module_get(aops->owner)) { + spin_unlock(&authtab_lock); *authp = rpc_autherr_badcred; return SVC_DENIED; } + spin_unlock(&authtab_lock); rqstp->rq_authop = aops; return aops->accept(rqstp, authp); @@ -66,24 +73,30 @@ int svc_authorise(struct svc_rqst *rqstp if (aops) rv = aops->release(rqstp); - /* FIXME should I count and release authops */ + module_put(aops->owner); return rv; } int svc_auth_register(rpc_authflavor_t flavor, struct auth_ops *aops) { - if (flavor >= RPC_AUTH_MAXFLAVOR || authtab[flavor]) - return -EINVAL; - authtab[flavor] = aops; - return 0; + int rv = -EINVAL; + spin_lock(&authtab_lock); + if (flavor < RPC_AUTH_MAXFLAVOR && authtab[flavor] != NULL) { + authtab[flavor] = aops; + rv = 0; + } + spin_unlock(&authtab_lock); + return rv; } void svc_auth_unregister(rpc_authflavor_t flavor) { + spin_lock(&authtab_lock); if (flavor < RPC_AUTH_MAXFLAVOR) authtab[flavor] = NULL; + spin_unlock(&authtab_lock); } /************************************************** diff -puN net/sunrpc/svcauth_unix.c~knfsd-5-of-11-gss_svc_module_refpatch net/sunrpc/svcauth_unix.c --- 25/net/sunrpc/svcauth_unix.c~knfsd-5-of-11-gss_svc_module_refpatch 2004-05-28 00:10:36.971126944 -0700 +++ 25-akpm/net/sunrpc/svcauth_unix.c 2004-05-28 00:10:36.977126032 -0700 @@ -1,5 +1,6 @@ #include #include +#include #include #include #include @@ -411,6 +412,7 @@ svcauth_null_release(struct svc_rqst *rq struct auth_ops svcauth_null = { .name = "null", + .owner = THIS_MODULE, .flavour = RPC_AUTH_NULL, .accept = svcauth_null_accept, .release = svcauth_null_release, @@ -515,6 +517,7 @@ svcauth_unix_release(struct svc_rqst *rq struct auth_ops svcauth_unix = { .name = "unix", + .owner = THIS_MODULE, .flavour = RPC_AUTH_UNIX, .accept = svcauth_unix_accept, .release = svcauth_unix_release, _