This is a note to let you know that I've just added the patch titled NFSv4 remove zero number of fs_locations entries error check to the 5.10-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: nfsv4-remove-zero-number-of-fs_locations-entries-err.patch and it can be found in the queue-5.10 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit 23454203172ab62038e4c9e477f53e90763bc78b Author: Olga Kornievskaia <kolga@xxxxxxxxxx> Date: Thu Dec 9 14:53:29 2021 -0500 NFSv4 remove zero number of fs_locations entries error check [ Upstream commit 90e12a3191040bd3854d3e236c35921e4e92a044 ] Remove the check for the zero length fs_locations reply in the xdr decoding, and instead check for that in the migration code. Signed-off-by: Olga Kornievskaia <kolga@xxxxxxxxxx> Signed-off-by: Anna Schumaker <Anna.Schumaker@xxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/fs/nfs/nfs4state.c b/fs/nfs/nfs4state.c index 4bf10792cb5b1..cbeec29e9f21a 100644 --- a/fs/nfs/nfs4state.c +++ b/fs/nfs/nfs4state.c @@ -2104,6 +2104,9 @@ static int nfs4_try_migration(struct nfs_server *server, const struct cred *cred } result = -NFS4ERR_NXIO; + if (!locations->nlocations) + goto out; + if (!(locations->fattr.valid & NFS_ATTR_FATTR_V4_LOCATIONS)) { dprintk("<-- %s: No fs_locations data, migration skipped\n", __func__); diff --git a/fs/nfs/nfs4xdr.c b/fs/nfs/nfs4xdr.c index 9f8bd45379e72..e2f0e3446e22a 100644 --- a/fs/nfs/nfs4xdr.c +++ b/fs/nfs/nfs4xdr.c @@ -3680,8 +3680,6 @@ static int decode_attr_fs_locations(struct xdr_stream *xdr, uint32_t *bitmap, st if (unlikely(!p)) goto out_eio; n = be32_to_cpup(p); - if (n <= 0) - goto out_eio; for (res->nlocations = 0; res->nlocations < n; res->nlocations++) { u32 m; struct nfs4_fs_location *loc;