From: Steve French stfrench@microsoft.com
[ Upstream commit c774e6779f38bf36f0cce65e30793704bab4b0d7 ]
umount can race with lease break so need to check if tcon->ses->server is still valid to send the lease break response.
Reviewed-by: Bharath SM bharathsm@microsoft.com Reviewed-by: Shyam Prasad N sprasad@microsoft.com Fixes: 59a556aebc43 ("SMB3: drop reference to cfile before sending oplock break") Signed-off-by: Steve French stfrench@microsoft.com Signed-off-by: Sasha Levin sashal@kernel.org --- fs/cifs/file.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-)
diff --git a/fs/cifs/file.c b/fs/cifs/file.c index 9a4c33ffb75fa..87dcffece7623 100644 --- a/fs/cifs/file.c +++ b/fs/cifs/file.c @@ -5146,9 +5146,13 @@ void cifs_oplock_break(struct work_struct *work) * disconnected since oplock already released by the server */ if (!oplock_break_cancelled) { - rc = tcon->ses->server->ops->oplock_response(tcon, persistent_fid, + /* check for server null since can race with kill_sb calling tree disconnect */ + if (tcon->ses && tcon->ses->server) { + rc = tcon->ses->server->ops->oplock_response(tcon, persistent_fid, volatile_fid, net_fid, cinode); - cifs_dbg(FYI, "Oplock release rc = %d\n", rc); + cifs_dbg(FYI, "Oplock release rc = %d\n", rc); + } else + pr_warn_once("lease break not sent for unmounted share\n"); }
cifs_done_oplock_break(cinode);