diff mbox series

[v2] SUNRPC: Check if the xprt is connected before handling sysfs reads

Message ID 20211028191741.167215-1-Anna.Schumaker@Netapp.com (mailing list archive)
State New, archived
Headers show
Series [v2] SUNRPC: Check if the xprt is connected before handling sysfs reads | expand

Commit Message

Anna Schumaker Oct. 28, 2021, 7:17 p.m. UTC 
From: Anna Schumaker <Anna.Schumaker@Netapp.com>

xprts don't immediately reconnect when changing the "dstaddr" property,
instead this gets handled the next time an operation uses the transport.
This could lead to NULL pointer dereferences when trying to read sysfs
files between the disconnect and reconnect operations. Fix this by
returning an error if the xprt is not connected.

Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
---
v2: Call xprt_put() on the xprt before returning
---
 net/sunrpc/sysfs.c | 12 ++++++++----
 1 file changed, 8 insertions(+), 4 deletions(-)
diff mbox series

Patch

diff --git a/net/sunrpc/sysfs.c b/net/sunrpc/sysfs.c
index 9a6f17e18f73..2766dd21935b 100644
--- a/net/sunrpc/sysfs.c
+++ b/net/sunrpc/sysfs.c
@@ -109,8 +109,10 @@  static ssize_t rpc_sysfs_xprt_srcaddr_show(struct kobject *kobj,
 	struct sock_xprt *sock;
 	ssize_t ret = -1;
 
-	if (!xprt)
-		return 0;
+	if (!xprt || !xprt_connected(xprt)) {
+		xprt_put(xprt);
+		return -ENOTCONN;
+	}
 
 	sock = container_of(xprt, struct sock_xprt, xprt);
 	if (kernel_getsockname(sock->sock, (struct sockaddr *)&saddr) < 0)
@@ -129,8 +131,10 @@  static ssize_t rpc_sysfs_xprt_info_show(struct kobject *kobj,
 	struct rpc_xprt *xprt = rpc_sysfs_xprt_kobj_get_xprt(kobj);
 	ssize_t ret;
 
-	if (!xprt)
-		return 0;
+	if (!xprt || !xprt_connected(xprt)) {
+		xprt_put(xprt);
+		return -ENOTCONN;
+	}
 
 	ret = sprintf(buf, "last_used=%lu\ncur_cong=%lu\ncong_win=%lu\n"
 		       "max_num_slots=%u\nmin_num_slots=%u\nnum_reqs=%u\n"