@@ -689,13 +689,19 @@ smb2_close_cached_fid(struct kref *ref)
cifs_dbg(FYI, "clear cached root file handle\n");
SMB2_close(0, cfid->tcon, cfid->fid->persistent_fid,
cfid->fid->volatile_fid);
- cfid->is_valid = false;
- cfid->file_all_info_is_valid = false;
- cfid->has_lease = false;
- if (cfid->dentry) {
- dput(cfid->dentry);
- cfid->dentry = NULL;
- }
+ }
+
+ /*
+ * We only check validity above to send SMB2_close,
+ * but we still need to invalidate these entries
+ * when this function is called
+ */
+ cfid->is_valid = false;
+ cfid->file_all_info_is_valid = false;
+ cfid->has_lease = false;
+ if (cfid->dentry) {
+ dput(cfid->dentry);
+ cfid->dentry = NULL;
}
}
Cached root file was not being completely invalidated sometimes. Reproducing: - With a DFS share with 2 targets, one disabled and one enabled - start some I/O on the mount # while true; do ls /mnt/dfs; done - at the same time, disable the enabled target and enable the disabled one - wait for DFS cache to expire - on reconnect, the previous cached root handle should be invalid, but open_cached_dir_by_dentry() will still try to use it, but throws a use-after-free warning (kref_get()) Make smb2_close_cached_fid() invalidate all fields every time, but only send an SMB2_close() when the entry is still valid. Signed-off-by: Enzo Matsumiya <ematsumiya@suse.de> --- fs/cifs/smb2ops.c | 20 +++++++++++++------- 1 file changed, 13 insertions(+), 7 deletions(-)