Fix dereference before null check warning

null tcon is not likely in these paths in current code, but obviously it does clarify the code to check for null (if at all) before derefrencing rather than after. Reported by Coverity (CID 1042666) Signed-off-by: Steve French <[email protected]> Acked-by: Shirish Pargaonkar <[email protected]> Acked-by: Sachin Prabhu <[email protected]>
jledet · Apr 1, 2015 · 8e35310 · 8e35310
1 parent f3a31a2
commit 8e35310
Showing 1 changed file with 8 additions and 5 deletions.
diff --git a/fs/cifs/smb2pdu.c b/fs/cifs/smb2pdu.c
@@ -1218,7 +1218,7 @@ SMB2_ioctl(const unsigned int xid, struct cifs_tcon *tcon, u64 persistent_fid,
 	struct smb2_ioctl_req *req;
 	struct smb2_ioctl_rsp *rsp;
 	struct TCP_Server_Info *server;
-	struct cifs_ses *ses = tcon->ses;
+	struct cifs_ses *ses;
 	struct kvec iov[2];
 	int resp_buftype;
 	int num_iovecs;
@@ -1233,6 +1233,11 @@ SMB2_ioctl(const unsigned int xid, struct cifs_tcon *tcon, u64 persistent_fid,
 	if (plen)
 		*plen = 0;
 
+	if (tcon)
+		ses = tcon->ses;
+	else
+		return -EIO;
+
 	if (ses && (ses->server))
 		server = ses->server;
 	else
@@ -1296,14 +1301,12 @@ SMB2_ioctl(const unsigned int xid, struct cifs_tcon *tcon, u64 persistent_fid,
 	rsp = (struct smb2_ioctl_rsp *)iov[0].iov_base;
 
 	if ((rc != 0) && (rc != -EINVAL)) {
-		if (tcon)
-			cifs_stats_fail_inc(tcon, SMB2_IOCTL_HE);
+		cifs_stats_fail_inc(tcon, SMB2_IOCTL_HE);
 		goto ioctl_exit;
 	} else if (rc == -EINVAL) {
 		if ((opcode != FSCTL_SRV_COPYCHUNK_WRITE) &&
 		    (opcode != FSCTL_SRV_COPYCHUNK)) {
-			if (tcon)
-				cifs_stats_fail_inc(tcon, SMB2_IOCTL_HE);
+			cifs_stats_fail_inc(tcon, SMB2_IOCTL_HE);
 			goto ioctl_exit;
 		}
 	}