diff options
author | NeilBrown <neilb@suse.de> | 2023-05-09 01:42:47 +0200 |
---|---|---|
committer | Chuck Lever <chuck.lever@oracle.com> | 2023-05-14 21:55:02 +0200 |
commit | 948f072ada23e0a504c5e4d7d71d4c83bd0785ec (patch) | |
tree | 35e02b9a854af2107953dc9e7150bc98be37e453 /net/sunrpc/xprtrdma | |
parent | SUNRPC: double free xprt_ctxt while still in use (diff) | |
download | linux-948f072ada23e0a504c5e4d7d71d4c83bd0785ec.tar.xz linux-948f072ada23e0a504c5e4d7d71d4c83bd0785ec.zip |
SUNRPC: always free ctxt when freeing deferred request
Since the ->xprt_ctxt pointer was added to svc_deferred_req, it has not
been sufficient to use kfree() to free a deferred request. We may need
to free the ctxt as well.
As freeing the ctxt is all that ->xpo_release_rqst() does, we repurpose
it to explicit do that even when the ctxt is not stored in an rqst.
So we now have ->xpo_release_ctxt() which is given an xprt and a ctxt,
which may have been taken either from an rqst or from a dreq. The
caller is now responsible for clearing that pointer after the call to
->xpo_release_ctxt.
We also clear dr->xprt_ctxt when the ctxt is moved into a new rqst when
revisiting a deferred request. This ensures there is only one pointer
to the ctxt, so the risk of double freeing in future is reduced. The
new code in svc_xprt_release which releases both the ctxt and any
rq_deferred depends on this.
Fixes: 773f91b2cf3f ("SUNRPC: Fix NFSD's request deferral on RDMA transports")
Signed-off-by: NeilBrown <neilb@suse.de>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Diffstat (limited to 'net/sunrpc/xprtrdma')
-rw-r--r-- | net/sunrpc/xprtrdma/svc_rdma_recvfrom.c | 11 | ||||
-rw-r--r-- | net/sunrpc/xprtrdma/svc_rdma_transport.c | 2 |
2 files changed, 6 insertions, 7 deletions
diff --git a/net/sunrpc/xprtrdma/svc_rdma_recvfrom.c b/net/sunrpc/xprtrdma/svc_rdma_recvfrom.c index 1c658fa43063..a22fe7587fa6 100644 --- a/net/sunrpc/xprtrdma/svc_rdma_recvfrom.c +++ b/net/sunrpc/xprtrdma/svc_rdma_recvfrom.c @@ -239,21 +239,20 @@ void svc_rdma_recv_ctxt_put(struct svcxprt_rdma *rdma, } /** - * svc_rdma_release_rqst - Release transport-specific per-rqst resources - * @rqstp: svc_rqst being released + * svc_rdma_release_ctxt - Release transport-specific per-rqst resources + * @xprt: the transport which owned the context + * @vctxt: the context from rqstp->rq_xprt_ctxt or dr->xprt_ctxt * * Ensure that the recv_ctxt is released whether or not a Reply * was sent. For example, the client could close the connection, * or svc_process could drop an RPC, before the Reply is sent. */ -void svc_rdma_release_rqst(struct svc_rqst *rqstp) +void svc_rdma_release_ctxt(struct svc_xprt *xprt, void *vctxt) { - struct svc_rdma_recv_ctxt *ctxt = rqstp->rq_xprt_ctxt; - struct svc_xprt *xprt = rqstp->rq_xprt; + struct svc_rdma_recv_ctxt *ctxt = vctxt; struct svcxprt_rdma *rdma = container_of(xprt, struct svcxprt_rdma, sc_xprt); - rqstp->rq_xprt_ctxt = NULL; if (ctxt) svc_rdma_recv_ctxt_put(rdma, ctxt); } diff --git a/net/sunrpc/xprtrdma/svc_rdma_transport.c b/net/sunrpc/xprtrdma/svc_rdma_transport.c index 416b298f74dd..ca04f7a6a085 100644 --- a/net/sunrpc/xprtrdma/svc_rdma_transport.c +++ b/net/sunrpc/xprtrdma/svc_rdma_transport.c @@ -80,7 +80,7 @@ static const struct svc_xprt_ops svc_rdma_ops = { .xpo_recvfrom = svc_rdma_recvfrom, .xpo_sendto = svc_rdma_sendto, .xpo_result_payload = svc_rdma_result_payload, - .xpo_release_rqst = svc_rdma_release_rqst, + .xpo_release_ctxt = svc_rdma_release_ctxt, .xpo_detach = svc_rdma_detach, .xpo_free = svc_rdma_free, .xpo_has_wspace = svc_rdma_has_wspace, |