1 files changed, 37 insertions, 35 deletions

diff --git a/fs/smb/client/smb2misc.c b/fs/smb/client/smb2misc.c
index 25f7cd6f23d6..677ef6f99a5b 100644
--- a/fs/smb/client/smb2misc.c
+++ b/fs/smb/client/smb2misc.c
@@ -173,6 +173,21 @@ smb2_check_message(char *buf, unsigned int len, struct TCP_Server_Info *server)
 	}
 
 	mid = le64_to_cpu(shdr->MessageId);
+	if (check_smb2_hdr(shdr, mid))
+		return 1;
+
+	if (shdr->StructureSize != SMB2_HEADER_STRUCTURE_SIZE) {
+		cifs_dbg(VFS, "Invalid structure size %u\n",
+			 le16_to_cpu(shdr->StructureSize));
+		return 1;
+	}
+
+	command = le16_to_cpu(shdr->Command);
+	if (command >= NUMBER_OF_SMB2_COMMANDS) {
+		cifs_dbg(VFS, "Invalid SMB2 command %d\n", command);
+		return 1;
+	}
+
 	if (len < pdu_size) {
 		if ((len >= hdr_size)
 		    && (shdr->Status != 0)) {
@@ -193,21 +208,6 @@ smb2_check_message(char *buf, unsigned int len, struct TCP_Server_Info *server)
 		return 1;
 	}
 
-	if (check_smb2_hdr(shdr, mid))
-		return 1;
-
-	if (shdr->StructureSize != SMB2_HEADER_STRUCTURE_SIZE) {
-		cifs_dbg(VFS, "Invalid structure size %u\n",
-			 le16_to_cpu(shdr->StructureSize));
-		return 1;
-	}
-
-	command = le16_to_cpu(shdr->Command);
-	if (command >= NUMBER_OF_SMB2_COMMANDS) {
-		cifs_dbg(VFS, "Invalid SMB2 command %d\n", command);
-		return 1;
-	}
-
 	if (smb2_rsp_struct_sizes[command] != pdu->StructureSize2) {
 		if (command != SMB2_OPLOCK_BREAK_HE && (shdr->Status == 0 ||
 		    pdu->StructureSize2 != SMB2_ERROR_STRUCTURE_SIZE2_LE)) {
@@ -313,6 +313,9 @@ static const bool has_smb2_data_area[NUMBER_OF_SMB2_COMMANDS] = {
 char *
 smb2_get_data_area_len(int *off, int *len, struct smb2_hdr *shdr)
 {
+	const int max_off = 4096;
+	const int max_len = 128 * 1024;
+
 	*off = 0;
 	*len = 0;
 
@@ -384,29 +387,20 @@ smb2_get_data_area_len(int *off, int *len, struct smb2_hdr *shdr)
 	 * Invalid length or offset probably means data area is invalid, but
 	 * we have little choice but to ignore the data area in this case.
 	 */
-	if (*off > 4096) {
-		cifs_dbg(VFS, "offset %d too large, data area ignored\n", *off);
-		*len = 0;
+	if (unlikely(*off < 0 || *off > max_off ||
+		     *len < 0 || *len > max_len)) {
+		cifs_dbg(VFS, "%s: invalid data area (off=%d len=%d)\n",
+			 __func__, *off, *len);
 		*off = 0;
-	} else if (*off < 0) {
-		cifs_dbg(VFS, "negative offset %d to data invalid ignore data area\n",
-			 *off);
-		*off = 0;
-		*len = 0;
-	} else if (*len < 0) {
-		cifs_dbg(VFS, "negative data length %d invalid, data area ignored\n",
-			 *len);
 		*len = 0;
-	} else if (*len > 128 * 1024) {
-		cifs_dbg(VFS, "data area larger than 128K: %d\n", *len);
+	} else if (*off == 0) {
 		*len = 0;
 	}
 
 	/* return pointer to beginning of data area, ie offset from SMB start */
-	if ((*off != 0) && (*len != 0))
+	if (*off > 0 && *len > 0)
 		return (char *)shdr + *off;
-	else
-		return NULL;
+	return NULL;
 }
 
 /*
@@ -628,6 +622,8 @@ smb2_is_valid_lease_break(char *buffer, struct TCP_Server_Info *server)
 	/* look up tcon based on tid & uid */
 	spin_lock(&cifs_tcp_ses_lock);
 	list_for_each_entry(ses, &pserver->smb_ses_list, smb_ses_list) {
+		if (cifs_ses_exiting(ses))
+			continue;
 		list_for_each_entry(tcon, &ses->tcon_list, tcon_list) {
 			spin_lock(&tcon->open_file_lock);
 			cifs_stats_inc(
@@ -703,6 +699,8 @@ smb2_is_valid_oplock_break(char *buffer, struct TCP_Server_Info *server)
 	/* look up tcon based on tid & uid */
 	spin_lock(&cifs_tcp_ses_lock);
 	list_for_each_entry(ses, &pserver->smb_ses_list, smb_ses_list) {
+		if (cifs_ses_exiting(ses))
+			continue;
 		list_for_each_entry(tcon, &ses->tcon_list, tcon_list) {
 
 			spin_lock(&tcon->open_file_lock);
@@ -769,7 +767,7 @@ smb2_cancelled_close_fid(struct work_struct *work)
 	if (rc)
 		cifs_tcon_dbg(VFS, "Close cancelled mid failed rc:%d\n", rc);
 
-	cifs_put_tcon(tcon);
+	cifs_put_tcon(tcon, netfs_trace_tcon_ref_put_cancelled_close_fid);
 	kfree(cancelled);
 }
 
@@ -787,7 +785,7 @@ __smb2_handle_cancelled_cmd(struct cifs_tcon *tcon, __u16 cmd, __u64 mid,
 {
 	struct close_cancelled_open *cancelled;
 
-	cancelled = kzalloc(sizeof(*cancelled), GFP_ATOMIC);
+	cancelled = kzalloc(sizeof(*cancelled), GFP_KERNEL);
 	if (!cancelled)
 		return -ENOMEM;
 
@@ -813,6 +811,8 @@ smb2_handle_cancelled_close(struct cifs_tcon *tcon, __u64 persistent_fid,
 	if (tcon->tc_count <= 0) {
 		struct TCP_Server_Info *server = NULL;
 
+		trace_smb3_tcon_ref(tcon->debug_id, tcon->tc_count,
+				    netfs_trace_tcon_ref_see_cancelled_close);
 		WARN_ONCE(tcon->tc_count < 0, "tcon refcount is negative");
 		spin_unlock(&cifs_tcp_ses_lock);
 
@@ -825,12 +825,14 @@ smb2_handle_cancelled_close(struct cifs_tcon *tcon, __u64 persistent_fid,
 		return 0;
 	}
 	tcon->tc_count++;
+	trace_smb3_tcon_ref(tcon->debug_id, tcon->tc_count,
+			    netfs_trace_tcon_ref_get_cancelled_close);
 	spin_unlock(&cifs_tcp_ses_lock);
 
 	rc = __smb2_handle_cancelled_cmd(tcon, SMB2_CLOSE_HE, 0,
 					 persistent_fid, volatile_fid);
 	if (rc)
-		cifs_put_tcon(tcon);
+		cifs_put_tcon(tcon, netfs_trace_tcon_ref_put_cancelled_close);
 
 	return rc;
 }
@@ -858,7 +860,7 @@ smb2_handle_cancelled_mid(struct mid_q_entry *mid, struct TCP_Server_Info *serve
 					 rsp->PersistentFileId,
 					 rsp->VolatileFileId);
 	if (rc)
-		cifs_put_tcon(tcon);
+		cifs_put_tcon(tcon, netfs_trace_tcon_ref_put_cancelled_mid);
 
 	return rc;
 }