[PATCH 4.14 20/43] sunrpc: fix refcount leak for rpc auth modules

Greg Kroah-Hartman
2021-03-22T13:13:39Z

From: Daniel Kobras <kobras@puzzle-itc.de>

commit f1442d6349a2e7bb7a6134791bdc26cb776c79af upstream.

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.

Signed-off-by: Daniel Kobras <kobras@puzzle-itc.de>
Fixes: 4d712ef1db05 ("svcauth_gss: Close connection when dropping an incoming message")
Link: https://lore.kernel.org/linux-nfs/3F1B347F-B809-478F-A1E9-0BE98E22B0F0@oracle.com/T/#t
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
net/sunrpc/svc.c | 6 ++++--
1 file changed, 4 insertions(+), 2 deletions(-)

--- a/net/sunrpc/svc.c
+++ b/net/sunrpc/svc.c
@@ -1329,7 +1329,7 @@ svc_process_common(struct svc_rqst *rqst

sendit:
if (svc_authorise(rqstp))
- goto close;
+ goto close_xprt;
return 1; /* Caller can now send it */

dropit:
@@ -1338,6 +1338,8 @@ svc_process_common(struct svc_rqst *rqst
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");
@@ -1346,7 +1348,7 @@ svc_process_common(struct svc_rqst *rqst
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++;