| Message ID | 20200221202138.3744133-1-smayhew@redhat.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | NFS: Ensure the fs_context has the correct fs_type before mounting | expand |
diff --git a/fs/nfs/fs_context.c b/fs/nfs/fs_context.c index e1b938457ab9..b616263b0eb6 100644 --- a/fs/nfs/fs_context.c +++ b/fs/nfs/fs_context.c @@ -1240,6 +1240,13 @@ static int nfs_fs_context_validate(struct fs_context *fc) } ctx->nfs_mod = nfs_mod; } + + /* Ensure the filesystem context has the correct fs_type */ + if (fc->fs_type != ctx->nfs_mod->nfs_fs) { + module_put(fc->fs_type->owner); + __module_get(ctx->nfs_mod->nfs_fs->owner); + fc->fs_type = ctx->nfs_mod->nfs_fs; + } return 0; out_no_device_name:
This is necessary because unless userspace explicitly requests fstype "nfs4" (either via "mount -t nfs4" or by calling the "mount.nfs4" helper directly), the fstype will default to "nfs". This was fine on older kernels because the super_block->s_type was set via mount_info->nfs_mod->nfs_fs, which was set when parsing the mount options and subsequently passed in the "type" argument of sget(). After commit f2aedb713c28 ("NFS: Add fs_context support."), sget_fc(), which has no "type" argument, is called instead. In sget_fc(), the super_block->s_type is set via fs_context->fs_type, which was set when the filesystem context was initially created. Reported-by: Patrick Steinhardt <ps@pks.im> Fixes: f2aedb713c28 ("NFS: Add fs_context support.") Signed-off-by: Scott Mayhew <smayhew@redhat.com> --- fs/nfs/fs_context.c | 7 +++++++ 1 file changed, 7 insertions(+)