CIFS: Fix missing lease break

If a server sends a lease break to a connection that doesn't have
opens with a lease key specified in the server response, we can't
find an open file to send an ack. Fix this by walking through
all connections we have.

Cc: <stable@vger.kernel.org>
Signed-off-by: Pavel Shilovsky <pshilovsky@samba.org>
Signed-off-by: Steve French <smfrench@gmail.com>

1 files changed, 80 insertions, 69 deletions

diff --git a/fs/cifs/smb2misc.c b/fs/cifs/smb2misc.c
index 38c93c305c9e..314bd60f30ce 100644
--- a/fs/cifs/smb2misc.c
+++ b/fs/cifs/smb2misc.c
@@ -421,97 +421,108 @@ cifs_ses_oplock_break(struct work_struct *work)
 }
 
 static bool
-smb2_is_valid_lease_break(char *buffer, struct TCP_Server_Info *server)
+smb2_tcon_has_lease(struct cifs_tcon *tcon, struct smb2_lease_break *rsp,
+                    struct smb2_lease_break_work *lw)
 {
-        struct smb2_lease_break *rsp = (struct smb2_lease_break *)buffer;
-        struct list_head *tmp, *tmp1, *tmp2;
-        struct cifs_ses *ses;
-        struct cifs_tcon *tcon;
-        struct cifsInodeInfo *cinode;
+        bool found;
+        __u8 lease_state;
+        struct list_head *tmp;
         struct cifsFileInfo *cfile;
         struct cifs_pending_open *open;
-        struct smb2_lease_break_work *lw;
-        bool found;
+        struct cifsInodeInfo *cinode;
         int ack_req = le32_to_cpu(rsp->Flags &
                                   SMB2_NOTIFY_BREAK_LEASE_FLAG_ACK_REQUIRED);
 
-        lw = kmalloc(sizeof(struct smb2_lease_break_work), GFP_KERNEL);
-        if (!lw)
-                return false;
+        lease_state = smb2_map_lease_to_oplock(rsp->NewLeaseState);
 
-        INIT_WORK(&lw->lease_break, cifs_ses_oplock_break);
-        lw->lease_state = rsp->NewLeaseState;
+        list_for_each(tmp, &tcon->openFileList) {
+                cfile = list_entry(tmp, struct cifsFileInfo, tlist);
+                cinode = CIFS_I(cfile->dentry->d_inode);
 
-        cifs_dbg(FYI, "Checking for lease break\n");
+                if (memcmp(cinode->lease_key, rsp->LeaseKey,
+                                                        SMB2_LEASE_KEY_SIZE))
+                        continue;
 
-        /* look up tcon based on tid & uid */
-        spin_lock(&cifs_tcp_ses_lock);
-        list_for_each(tmp, &server->smb_ses_list) {
-                ses = list_entry(tmp, struct cifs_ses, smb_ses_list);
+                cifs_dbg(FYI, "found in the open list\n");
+                cifs_dbg(FYI, "lease key match, lease break 0x%d\n",
+                         le32_to_cpu(rsp->NewLeaseState));
 
-                spin_lock(&cifs_file_list_lock);
-                list_for_each(tmp1, &ses->tcon_list) {
-                        tcon = list_entry(tmp1, struct cifs_tcon, tcon_list);
+                smb2_set_oplock_level(cinode, lease_state);
 
-                        cifs_stats_inc(&tcon->stats.cifs_stats.num_oplock_brks);
-                        list_for_each(tmp2, &tcon->openFileList) {
-                                cfile = list_entry(tmp2, struct cifsFileInfo,
-                                                   tlist);
-                                cinode = CIFS_I(cfile->dentry->d_inode);
+                if (ack_req)
+                        cfile->oplock_break_cancelled = false;
+                else
+                        cfile->oplock_break_cancelled = true;
 
-                                if (memcmp(cinode->lease_key, rsp->LeaseKey,
-                                           SMB2_LEASE_KEY_SIZE))
-                                        continue;
+                queue_work(cifsiod_wq, &cfile->oplock_break);
+                kfree(lw);
+                return true;
+        }
 
-                                cifs_dbg(FYI, "found in the open list\n");
-                                cifs_dbg(FYI, "lease key match, lease break 0x%d\n",
-                                         le32_to_cpu(rsp->NewLeaseState));
+        found = false;
+        list_for_each_entry(open, &tcon->pending_opens, olist) {
+                if (memcmp(open->lease_key, rsp->LeaseKey,
+                           SMB2_LEASE_KEY_SIZE))
+                        continue;
+
+                if (!found && ack_req) {
+                        found = true;
+                        memcpy(lw->lease_key, open->lease_key,
+                               SMB2_LEASE_KEY_SIZE);
+                        lw->tlink = cifs_get_tlink(open->tlink);
+                        queue_work(cifsiod_wq, &lw->lease_break);
+                }
 
-                                smb2_set_oplock_level(cinode,
-                                  smb2_map_lease_to_oplock(rsp->NewLeaseState));
+                cifs_dbg(FYI, "found in the pending open list\n");
+                cifs_dbg(FYI, "lease key match, lease break 0x%d\n",
+                         le32_to_cpu(rsp->NewLeaseState));
 
-                                if (ack_req)
-                                        cfile->oplock_break_cancelled = false;
-                                else
-                                        cfile->oplock_break_cancelled = true;
+                open->oplock = lease_state;
+        }
+        return found;
+}
 
-                                queue_work(cifsiod_wq, &cfile->oplock_break);
+static bool
+smb2_is_valid_lease_break(char *buffer)
+{
+        struct smb2_lease_break *rsp = (struct smb2_lease_break *)buffer;
+        struct list_head *tmp, *tmp1, *tmp2;
+        struct TCP_Server_Info *server;
+        struct cifs_ses *ses;
+        struct cifs_tcon *tcon;
+        struct smb2_lease_break_work *lw;
 
-                                kfree(lw);
-                                spin_unlock(&cifs_file_list_lock);
-                                spin_unlock(&cifs_tcp_ses_lock);
-                                return true;
-                        }
+        lw = kmalloc(sizeof(struct smb2_lease_break_work), GFP_KERNEL);
+        if (!lw)
+                return false;
 
-                        found = false;
-                        list_for_each_entry(open, &tcon->pending_opens, olist) {
-                                if (memcmp(open->lease_key, rsp->LeaseKey,
-                                           SMB2_LEASE_KEY_SIZE))
-                                        continue;
+        INIT_WORK(&lw->lease_break, cifs_ses_oplock_break);
+        lw->lease_state = rsp->NewLeaseState;
 
-                                if (!found && ack_req) {
-                                        found = true;
-                                        memcpy(lw->lease_key, open->lease_key,
-                                               SMB2_LEASE_KEY_SIZE);
-                                        lw->tlink = cifs_get_tlink(open->tlink);
-                                        queue_work(cifsiod_wq,
-                                                   &lw->lease_break);
-                                }
+        cifs_dbg(FYI, "Checking for lease break\n");
+
+        /* look up tcon based on tid & uid */
+        spin_lock(&cifs_tcp_ses_lock);
+        list_for_each(tmp, &cifs_tcp_ses_list) {
+                server = list_entry(tmp, struct TCP_Server_Info, tcp_ses_list);
 
-                                cifs_dbg(FYI, "found in the pending open list\n");
-                                cifs_dbg(FYI, "lease key match, lease break 0x%d\n",
-                                         le32_to_cpu(rsp->NewLeaseState));
+                list_for_each(tmp1, &server->smb_ses_list) {
+                        ses = list_entry(tmp1, struct cifs_ses, smb_ses_list);
 
-                                open->oplock =
-                                  smb2_map_lease_to_oplock(rsp->NewLeaseState);
-                        }
-                        if (found) {
-                                spin_unlock(&cifs_file_list_lock);
-                                spin_unlock(&cifs_tcp_ses_lock);
-                                return true;
+                        spin_lock(&cifs_file_list_lock);
+                        list_for_each(tmp2, &ses->tcon_list) {
+                                tcon = list_entry(tmp2, struct cifs_tcon,
+                                                  tcon_list);
+                                cifs_stats_inc(
+                                    &tcon->stats.cifs_stats.num_oplock_brks);
+                                if (smb2_tcon_has_lease(tcon, rsp, lw)) {
+                                        spin_unlock(&cifs_file_list_lock);
+                                        spin_unlock(&cifs_tcp_ses_lock);
+                                        return true;
+                                }
                         }
+                        spin_unlock(&cifs_file_list_lock);
                 }
-                spin_unlock(&cifs_file_list_lock);
         }
         spin_unlock(&cifs_tcp_ses_lock);
         kfree(lw);
@@ -537,7 +548,7 @@ smb2_is_valid_oplock_break(char *buffer, struct TCP_Server_Info *server)
         if (rsp->StructureSize !=
                                 smb2_rsp_struct_sizes[SMB2_OPLOCK_BREAK_HE]) {
                 if (le16_to_cpu(rsp->StructureSize) == 44)
-                        return smb2_is_valid_lease_break(buffer, server);
+                        return smb2_is_valid_lease_break(buffer);
                 else
                         return false;
         }