git.ipfire.org Git - thirdparty/kernel/stable-queue.git/blob

   1 From 20b1aa912316ffb7fbb5f407f17c330f2a22ddff Mon Sep 17 00:00:00 2001
   2 From: Meetakshi Setiya <msetiya@microsoft.com>
   3 Date: Wed, 8 Jan 2025 05:10:34 -0500
   4 Subject: smb: client: sync the root session and superblock context passwords before automounting
   5
   6 From: Meetakshi Setiya <msetiya@microsoft.com>
   7
   8 commit 20b1aa912316ffb7fbb5f407f17c330f2a22ddff upstream.
   9
  10 In some cases, when password2 becomes the working password, the
  11 client swaps the two password fields in the root session struct, but
  12 not in the smb3_fs_context struct in cifs_sb. DFS automounts inherit
  13 fs context from their parent mounts. Therefore, they might end up
  14 getting the passwords in the stale order.
  15 The automount should succeed, because the mount function will end up
  16 retrying with the actual password anyway. But to reduce these
  17 unnecessary session setup retries for automounts, we can sync the
  18 parent context's passwords with the root session's passwords before
  19 duplicating it to the child's fs context.
  20
  21 Cc: stable@vger.kernel.org
  22 Signed-off-by: Meetakshi Setiya <msetiya@microsoft.com>
  23 Reviewed-by: Shyam Prasad N <sprasad@microsoft.com>
  24 Acked-by: Paulo Alcantara (Red Hat) <pc@manguebit.com>
  25 Signed-off-by: Steve French <stfrench@microsoft.com>
  26 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
  27 ---
  28  fs/smb/client/namespace.c |   19 ++++++++++++++++++-
  29  1 file changed, 18 insertions(+), 1 deletion(-)
  30
  31 --- a/fs/smb/client/namespace.c
  32 +++ b/fs/smb/client/namespace.c
  33 @@ -196,11 +196,28 @@ static struct vfsmount *cifs_do_automoun
  34         struct smb3_fs_context tmp;
  35         char *full_path;
  36         struct vfsmount *mnt;
  37 +       struct cifs_sb_info *mntpt_sb;
  38 +       struct cifs_ses *ses;
  39
  40         if (IS_ROOT(mntpt))
  41                 return ERR_PTR(-ESTALE);
  42
  43 -       cur_ctx = CIFS_SB(mntpt->d_sb)->ctx;
  44 +       mntpt_sb = CIFS_SB(mntpt->d_sb);
  45 +       ses = cifs_sb_master_tcon(mntpt_sb)->ses;
  46 +       cur_ctx = mntpt_sb->ctx;
  47 +
  48 +       /*
  49 +        * At this point, the root session should be in the mntpt sb. We should
  50 +        * bring the sb context passwords in sync with the root session's
  51 +        * passwords. This would help prevent unnecessary retries and password
  52 +        * swaps for automounts.
  53 +        */
  54 +       mutex_lock(&ses->session_mutex);
  55 +       rc = smb3_sync_session_ctx_passwords(mntpt_sb, ses);
  56 +       mutex_unlock(&ses->session_mutex);
  57 +
  58 +       if (rc)
  59 +               return ERR_PTR(rc);
  60
  61         fc = fs_context_for_submount(path->mnt->mnt_sb->s_type, mntpt);
  62         if (IS_ERR(fc))