[PATCH AUTOSEL 4.19 131/206] svcrdma: Fix leak of transport addresses

From: Sasha Levin
Date: Thu Sep 17 2020 - 22:10:53 EST


From: Chuck Lever <chuck.lever@xxxxxxxxxx>

[ Upstream commit 1a33d8a284b1e85e03b8c7b1ea8fb985fccd1d71 ]

Kernel memory leak detected:

unreferenced object 0xffff888849cdf480 (size 8):
comm "kworker/u8:3", pid 2086, jiffies 4297898756 (age 4269.856s)
hex dump (first 8 bytes):
30 00 cd 49 88 88 ff ff 0..I....
backtrace:
[<00000000acfc370b>] __kmalloc_track_caller+0x137/0x183
[<00000000a2724354>] kstrdup+0x2b/0x43
[<0000000082964f84>] xprt_rdma_format_addresses+0x114/0x17d [rpcrdma]
[<00000000dfa6ed00>] xprt_setup_rdma_bc+0xc0/0x10c [rpcrdma]
[<0000000073051a83>] xprt_create_transport+0x3f/0x1a0 [sunrpc]
[<0000000053531a8e>] rpc_create+0x118/0x1cd [sunrpc]
[<000000003a51b5f8>] setup_callback_client+0x1a5/0x27d [nfsd]
[<000000001bd410af>] nfsd4_process_cb_update.isra.7+0x16c/0x1ac [nfsd]
[<000000007f4bbd56>] nfsd4_run_cb_work+0x4c/0xbd [nfsd]
[<0000000055c5586b>] process_one_work+0x1b2/0x2fe
[<00000000b1e3e8ef>] worker_thread+0x1a6/0x25a
[<000000005205fb78>] kthread+0xf6/0xfb
[<000000006d2dc057>] ret_from_fork+0x3a/0x50

Introduce a call to xprt_rdma_free_addresses() similar to the way
that the TCP backchannel releases a transport's peer address
strings.

Fixes: 5d252f90a800 ("svcrdma: Add class for RDMA backwards direction transport")
Signed-off-by: Chuck Lever <chuck.lever@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
net/sunrpc/xprtrdma/svc_rdma_backchannel.c | 1 +
1 file changed, 1 insertion(+)

diff --git a/net/sunrpc/xprtrdma/svc_rdma_backchannel.c b/net/sunrpc/xprtrdma/svc_rdma_backchannel.c
index b9827665ff355..d183d4aee822c 100644
--- a/net/sunrpc/xprtrdma/svc_rdma_backchannel.c
+++ b/net/sunrpc/xprtrdma/svc_rdma_backchannel.c
@@ -256,6 +256,7 @@ xprt_rdma_bc_put(struct rpc_xprt *xprt)
{
dprintk("svcrdma: %s: xprt %p\n", __func__, xprt);

+ xprt_rdma_free_addresses(xprt);
xprt_free(xprt);
module_put(THIS_MODULE);
}
--
2.25.1