If an auth module's accept op returns SVC_CLOSE, svc_process_common()
enters a call path that does not call svc_authorise() before leaving the
function, and thus leaks a reference on the auth module's refcount. Hence,
make sure calls to svc_authenticate() and svc_authorise() are paired for
all call paths, to make sure rpc auth modules can be unloaded.
Fixes: 4d712ef1db05 ("svcauth_gss: Close connection when dropping an incoming message")
Signed-off-by: Daniel Kobras <kobras@xxxxxxxxxxxxx>
---
Hi!
While debugging NFS on a system with misconfigured krb5 settings, we noticed
a suspiciously high refcount on the auth_rpcgss module, despite all of its
consumers already unloaded. I wasn't able to analyze any further on the live
system, but had a look at the code afterwards, and found a path that seems
to leak references if the mechanism's accept() op shuts down a connection
early. Although I couldn't verify, this seem to be a plausible fix.
Kind regards,
Daniel
net/sunrpc/svc.c | 6 ++++--
1 file changed, 4 insertions(+), 2 deletions(-)
diff --git a/net/sunrpc/svc.c b/net/sunrpc/svc.c
index 61fb8a18552c..d76dc9d95d16 100644
--- a/net/sunrpc/svc.c
+++ b/net/sunrpc/svc.c
@@ -1413,7 +1413,7 @@ svc_process_common(struct svc_rqst *rqstp, struct kvec *argv, struct kvec *resv)
sendit:
if (svc_authorise(rqstp))
- goto close;
+ goto close_xprt;
return 1; /* Caller can now send it */
release_dropit:
@@ -1425,6 +1425,8 @@ svc_process_common(struct svc_rqst *rqstp, struct kvec *argv, struct kvec *resv)
return 0;
close:
+ svc_authorise(rqstp);
+close_xprt:
if (rqstp->rq_xprt && test_bit(XPT_TEMP, &rqstp->rq_xprt->xpt_flags))
svc_close_xprt(rqstp->rq_xprt);
dprintk("svc: svc_process close\n");
@@ -1433,7 +1435,7 @@ svc_process_common(struct svc_rqst *rqstp, struct kvec *argv, struct kvec *resv)
err_short_len:
svc_printk(rqstp, "short len %zd, dropping request\n",
argv->iov_len);
- goto close;
+ goto close_xprt;
err_bad_rpc:
serv->sv_stats->rpcbadfmt++;
--
2.25.1
--
Puzzle ITC Deutschland GmbH
Sitz der Gesellschaft: Eisenbahnstraße 1, 72072
Tübingen
Eingetragen am Amtsgericht Stuttgart HRB 765802
Geschäftsführer:
Lukas Kallies, Daniel Kobras, Mark Pröhl
