From: Xin Xiong xiongx18@fudan.edu.cn
commit bfc48f1b0505ffcb03a6d749139b7577d6b81ae0 upstream.
The issue happens on some error handling paths. When the function fails to grab the object `xprt`, it simply returns 0, forgetting to decrease the reference count of another object `xps`, which is increased by rpc_sysfs_xprt_kobj_get_xprt_switch(), causing refcount leaks. Also, the function forgets to check whether `xps` is valid before using it, which may result in NULL-dereferencing issues.
Fix it by adding proper error handling code when either `xprt` or `xps` is NULL.
Fixes: 5b7eb78486cd ("SUNRPC: take a xprt offline using sysfs") Signed-off-by: Xin Xiong xiongx18@fudan.edu.cn Signed-off-by: Xin Tan tanxin.ctf@gmail.com Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- net/sunrpc/sysfs.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-)
--- a/net/sunrpc/sysfs.c +++ b/net/sunrpc/sysfs.c @@ -291,8 +291,10 @@ static ssize_t rpc_sysfs_xprt_state_chan int offline = 0, online = 0, remove = 0; struct rpc_xprt_switch *xps = rpc_sysfs_xprt_kobj_get_xprt_switch(kobj);
- if (!xprt) - return 0; + if (!xprt || !xps) { + count = 0; + goto out_put; + }
if (!strncmp(buf, "offline", 7)) offline = 1;