SMB3: drop reference to cfile before sending oplock break

In cifs_oplock_break function we drop reference to a cfile at
the end of function, due to which close command goes on wire
after lease break acknowledgment even if file is already closed
by application but we had deferred the handle close.
If other client with limited file shareaccess waiting on lease
break ack proceeds operation on that file as soon as first client
sends ack, then we may encounter status sharing violation error
because of open handle.
Solution is to put reference to cfile(send close on wire if last ref)
and then send oplock acknowledgment to server.

Fixes: 9e31678fb403 ("SMB3: fix lease break timeout when multiple deferred close handles for the same file.")
Cc: stable@kernel.org
Signed-off-by: Bharath SM <bharathsm@microsoft.com>
Reviewed-by: Shyam Prasad N <sprasad@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>

diff --git a/fs/cifs/cifsglob.h b/fs/cifs/cifsglob.h
index 01f0146ae0597350de32aec4ed540b7a1ee28f83..da490617aaed4ea747e3aad3d908a01616f91c01 100644 (file)
--- a/fs/cifs/cifsglob.h
+++ b/fs/cifs/cifsglob.h
@@ -424,8 +424,8 @@ struct smb_version_operations {
        /* check for STATUS_NETWORK_SESSION_EXPIRED */
        bool (*is_session_expired)(char *);
        /* send oplock break response */
-       int (*oplock_response)(struct cifs_tcon *, struct cifs_fid *,
-                              struct cifsInodeInfo *);
+       int (*oplock_response)(struct cifs_tcon *tcon, __u64 persistent_fid, __u64 volatile_fid,
+                       __u16 net_fid, struct cifsInodeInfo *cifs_inode);
        /* query remote filesystem */
        int (*queryfs)(const unsigned int, struct cifs_tcon *,
                       struct cifs_sb_info *, struct kstatfs *);

diff --git a/fs/cifs/file.c b/fs/cifs/file.c
index 79e08727eb501de7b1d4f5dd603e46765b181456..ba79c89ad114e01ade8a5062d5a7a08f5114dbe5 100644 (file)
--- a/fs/cifs/file.c
+++ b/fs/cifs/file.c
@@ -5134,7 +5134,9 @@ void cifs_oplock_break(struct work_struct *work)
        struct cifs_tcon *tcon = tlink_tcon(cfile->tlink);
        struct TCP_Server_Info *server = tcon->ses->server;
        int rc = 0;
-       bool purge_cache = false;
+       bool purge_cache = false, oplock_break_cancelled;
+       __u64 persistent_fid, volatile_fid;
+       __u16 net_fid;
 
        wait_on_bit(&cinode->flags, CIFS_INODE_PENDING_WRITERS,
                        TASK_UNINTERRUPTIBLE);
@@ -5179,19 +5181,24 @@ oplock_break_ack:
        if (!CIFS_CACHE_HANDLE(cinode) && !list_empty(&cinode->deferred_closes))
                cifs_close_deferred_file(cinode);
 
+       persistent_fid = cfile->fid.persistent_fid;
+       volatile_fid = cfile->fid.volatile_fid;
+       net_fid = cfile->fid.netfid;
+       oplock_break_cancelled = cfile->oplock_break_cancelled;
+
+       _cifsFileInfo_put(cfile, false /* do not wait for ourself */, false);
        /*
         * releasing stale oplock after recent reconnect of smb session using
         * a now incorrect file handle is not a data integrity issue but do
         * not bother sending an oplock release if session to server still is
         * disconnected since oplock already released by the server
         */
-       if (!cfile->oplock_break_cancelled) {
-               rc = tcon->ses->server->ops->oplock_response(tcon, &cfile->fid,
-                                                            cinode);
+       if (!oplock_break_cancelled) {
+               rc = tcon->ses->server->ops->oplock_response(tcon, persistent_fid,
+                               volatile_fid, net_fid, cinode);
                cifs_dbg(FYI, "Oplock release rc = %d\n", rc);
        }
 
-       _cifsFileInfo_put(cfile, false /* do not wait for ourself */, false);
        cifs_done_oplock_break(cinode);
 }
 

diff --git a/fs/cifs/smb1ops.c b/fs/cifs/smb1ops.c
index abda6148be10f122cd4e2df60f19239e2165b344..7d1b3fc014d94ac9dd1c9364c99e7e4a4b363359 100644 (file)
--- a/fs/cifs/smb1ops.c
+++ b/fs/cifs/smb1ops.c
@@ -897,12 +897,11 @@ cifs_close_dir(const unsigned int xid, struct cifs_tcon *tcon,
 }
 
 static int
-cifs_oplock_response(struct cifs_tcon *tcon, struct cifs_fid *fid,
-                    struct cifsInodeInfo *cinode)
+cifs_oplock_response(struct cifs_tcon *tcon, __u64 persistent_fid,
+               __u64 volatile_fid, __u16 net_fid, struct cifsInodeInfo *cinode)
 {
-       return CIFSSMBLock(0, tcon, fid->netfid, current->tgid, 0, 0, 0, 0,
-                          LOCKING_ANDX_OPLOCK_RELEASE, false,
-                          CIFS_CACHE_READ(cinode) ? 1 : 0);
+       return CIFSSMBLock(0, tcon, net_fid, current->tgid, 0, 0, 0, 0,
+                          LOCKING_ANDX_OPLOCK_RELEASE, false, CIFS_CACHE_READ(cinode) ? 1 : 0);
 }
 
 static int

diff --git a/fs/cifs/smb2ops.c b/fs/cifs/smb2ops.c
index d67fb23c22cee7c3e1dbab8e99feb0a96aea4232..3af587ff6645a70727cb44b32691b17805f8009d 100644 (file)
--- a/fs/cifs/smb2ops.c
+++ b/fs/cifs/smb2ops.c
@@ -2383,15 +2383,14 @@ smb2_is_network_name_deleted(char *buf, struct TCP_Server_Info *server)
 }
 
 static int
-smb2_oplock_response(struct cifs_tcon *tcon, struct cifs_fid *fid,
-                    struct cifsInodeInfo *cinode)
+smb2_oplock_response(struct cifs_tcon *tcon, __u64 persistent_fid,
+               __u64 volatile_fid, __u16 net_fid, struct cifsInodeInfo *cinode)
 {
        if (tcon->ses->server->capabilities & SMB2_GLOBAL_CAP_LEASING)
                return SMB2_lease_break(0, tcon, cinode->lease_key,
                                        smb2_get_lease_state(cinode));
 
-       return SMB2_oplock_break(0, tcon, fid->persistent_fid,
-                                fid->volatile_fid,
+       return SMB2_oplock_break(0, tcon, persistent_fid, volatile_fid,
                                 CIFS_CACHE_READ(cinode) ? 1 : 0);
 }