From: Jeff Layton jlayton@kernel.org
[ Upstream commit 6ba434cb1a8d403ea9aad1b667c3ea3ad8b3191f ]
There are two different flavors of the nfsd4_copy struct. One is embedded in the compound and is used directly in synchronous copies. The other is dynamically allocated, refcounted and tracked in the client struture. For the embedded one, the cleanup just involves releasing any nfsd_files held on its behalf. For the async one, the cleanup is a bit more involved, and we need to dequeue it from lists, unhash it, etc.
There is at least one potential refcount leak in this code now. If the kthread_create call fails, then both the src and dst nfsd_files in the original nfsd4_copy object are leaked.
The cleanup in this codepath is also sort of weird. In the async copy case, we'll have up to four nfsd_file references (src and dst for both flavors of copy structure). They are both put at the end of nfsd4_do_async_copy, even though the ones held on behalf of the embedded one outlive that structure.
Change it so that we always clean up the nfsd_file refs held by the embedded copy structure before nfsd4_copy returns. Rework cleanup_async_copy to handle both inter and intra copies. Eliminate nfsd4_cleanup_intra_ssc since it now becomes a no-op.
Signed-off-by: Jeff Layton jlayton@kernel.org Signed-off-by: Chuck Lever chuck.lever@oracle.com Signed-off-by: Sasha Levin sashal@kernel.org --- fs/nfsd/nfs4proc.c | 23 ++++++++++------------- 1 file changed, 10 insertions(+), 13 deletions(-)
diff --git a/fs/nfsd/nfs4proc.c b/fs/nfsd/nfs4proc.c index 13603cb017346..9cc498916aa22 100644 --- a/fs/nfsd/nfs4proc.c +++ b/fs/nfsd/nfs4proc.c @@ -1530,7 +1530,6 @@ nfsd4_cleanup_inter_ssc(struct vfsmount *ss_mnt, struct file *filp, struct nfsd_net *nn = net_generic(dst->nf_net, nfsd_net_id);
nfs42_ssc_close(filp); - nfsd_file_put(dst); fput(filp);
if (!nn) { @@ -1597,13 +1596,6 @@ nfsd4_setup_intra_ssc(struct svc_rqst *rqstp, ©->nf_dst); }
-static void -nfsd4_cleanup_intra_ssc(struct nfsd_file *src, struct nfsd_file *dst) -{ - nfsd_file_put(src); - nfsd_file_put(dst); -} - static void nfsd4_cb_offload_release(struct nfsd4_callback *cb) { struct nfsd4_cb_offload *cbo = @@ -1718,12 +1710,18 @@ static void dup_copy_fields(struct nfsd4_copy *src, struct nfsd4_copy *dst) dst->ss_mnt = src->ss_mnt; }
+static void release_copy_files(struct nfsd4_copy *copy) +{ + if (copy->nf_src) + nfsd_file_put(copy->nf_src); + if (copy->nf_dst) + nfsd_file_put(copy->nf_dst); +} + static void cleanup_async_copy(struct nfsd4_copy *copy) { nfs4_free_copy_state(copy); - nfsd_file_put(copy->nf_dst); - if (!nfsd4_ssc_is_inter(copy)) - nfsd_file_put(copy->nf_src); + release_copy_files(copy); spin_lock(©->cp_clp->async_lock); list_del(©->copies); spin_unlock(©->cp_clp->async_lock); @@ -1783,7 +1781,6 @@ static int nfsd4_do_async_copy(void *data) } else { nfserr = nfsd4_do_copy(copy, copy->nf_src->nf_file, copy->nf_dst->nf_file, false); - nfsd4_cleanup_intra_ssc(copy->nf_src, copy->nf_dst); }
do_callback: @@ -1847,9 +1844,9 @@ nfsd4_copy(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate, } else { status = nfsd4_do_copy(copy, copy->nf_src->nf_file, copy->nf_dst->nf_file, true); - nfsd4_cleanup_intra_ssc(copy->nf_src, copy->nf_dst); } out: + release_copy_files(copy); return status; out_err: if (async_copy)