nfs: keep server info for remounts

With newer kernels that use fs_context for nfs mounts, remounts fail with
-EINVAL.

$ mount -t nfs -o nolock 10.0.0.1:/tmp/test /mnt/test/
$ mount -t nfs -o remount /mnt/test/
mount: mounting 10.0.0.1:/tmp/test on /mnt/test failed: Invalid argument

For remounts, the nfs server address and port are populated by
nfs_init_fs_context and later overwritten with 0x00 bytes by
nfs23_parse_monolithic. The remount then fails as the server address is
invalid.

Fix this by not overwriting nfs server info in nfs23_parse_monolithic if
we're doing a remount.

Fixes: f2aedb713c ("NFS: Add fs_context support.")
Signed-off-by: Martin Kaiser <martin@kaiser.cx>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
This commit is contained in:
Martin Kaiser 2024-04-14 19:01:09 +02:00 committed by Trond Myklebust
parent 37ffe06537
commit b322bf9e98

View File

@ -1114,9 +1114,12 @@ static int nfs23_parse_monolithic(struct fs_context *fc,
ctx->acdirmax = data->acdirmax;
ctx->need_mount = false;
memcpy(sap, &data->addr, sizeof(data->addr));
ctx->nfs_server.addrlen = sizeof(data->addr);
ctx->nfs_server.port = ntohs(data->addr.sin_port);
if (!is_remount_fc(fc)) {
memcpy(sap, &data->addr, sizeof(data->addr));
ctx->nfs_server.addrlen = sizeof(data->addr);
ctx->nfs_server.port = ntohs(data->addr.sin_port);
}
if (sap->ss_family != AF_INET ||
!nfs_verify_server_address(sap))
goto out_no_address;