diff options
| author | Steve French <stfrench@microsoft.com> | 2023-03-23 22:20:02 +0100 |
|---|---|---|
| committer | Steve French <stfrench@microsoft.com> | 2023-03-24 20:37:12 +0100 |
| commit | 491eafce1a51c457701351a4bf40733799745314 (patch) | |
| tree | 300db71a141c34da469ac2e96b58355b41d6ca8b /fs/cifs/cifsfs.c | |
| parent | cifs: fix dentry lookups in directory handle cache (diff) | |
| download | linux-491eafce1a51c457701351a4bf40733799745314.tar.xz linux-491eafce1a51c457701351a4bf40733799745314.zip | |
smb3: fix unusable share after force unmount failure
If user does forced unmount ("umount -f") while files are still open
on the share (as was seen in a Kubernetes example running on SMB3.1.1
mount) then we were marking the share as "TID_EXITING" in umount_begin()
which caused all subsequent operations (except write) to fail ... but
unfortunately when umount_begin() is called we do not know yet that
there are open files or active references on the share that would prevent
unmount from succeeding. Kubernetes had example when they were doing
umount -f when files were open which caused the share to become
unusable until the files were closed (and the umount retried).
Fix this so that TID_EXITING is not set until we are about to send
the tree disconnect (not at the beginning of forced umounts in
umount_begin) so that if "umount -f" fails (due to open files or
references) the mount is still usable.
Cc: stable@vger.kernel.org
Reviewed-by: Shyam Prasad N <sprasad@microsoft.com>
Reviewed-by: Paulo Alcantara (SUSE) <pc@manguebit.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Diffstat (limited to 'fs/cifs/cifsfs.c')
| -rw-r--r-- | fs/cifs/cifsfs.c | 9 |
1 files changed, 6 insertions, 3 deletions
diff --git a/fs/cifs/cifsfs.c b/fs/cifs/cifsfs.c index cbcf210d56e4..ac9034fce409 100644 --- a/fs/cifs/cifsfs.c +++ b/fs/cifs/cifsfs.c @@ -731,13 +731,16 @@ static void cifs_umount_begin(struct super_block *sb) spin_lock(&tcon->tc_lock); if ((tcon->tc_count > 1) || (tcon->status == TID_EXITING)) { /* we have other mounts to same share or we have - already tried to force umount this and woken up + already tried to umount this and woken up all waiting network requests, nothing to do */ spin_unlock(&tcon->tc_lock); spin_unlock(&cifs_tcp_ses_lock); return; - } else if (tcon->tc_count == 1) - tcon->status = TID_EXITING; + } + /* + * can not set tcon->status to TID_EXITING yet since we don't know if umount -f will + * fail later (e.g. due to open files). TID_EXITING will be set just before tdis req sent + */ spin_unlock(&tcon->tc_lock); spin_unlock(&cifs_tcp_ses_lock); |