libgfapi: Add proper NULL checks

Two spots check for NULL after the pointer in question has already been
dereferenced. Checked for NULL (and set errno when needed) at appripriate
spots, added a few NULL checks further up the stack, and some whitespace
cleanup.

BUG: 789278
CID: 1124800
CID: 1124805

Change-Id: I1dd4ad3f285cca36f4e3f739288f154ec120aebb
Signed-off-by: Jose A. Rivera <jarrpa@redhat.com>
Reviewed-on: http://review.gluster.org/6908
Reviewed-by: Shyamsundar Ranganathan <srangana@redhat.com>
Tested-by: Gluster Build System <jenkins@build.gluster.com>
Reviewed-by: Vijay Bellur <vbellur@redhat.com>

2 files changed, 44 insertions, 18 deletions

diff --git a/api/src/glfs-mgmt.c b/api/src/glfs-mgmt.c
index 6843e9cb3fe..afb351da03a 100644
--- a/api/src/glfs-mgmt.c
+++ b/api/src/glfs-mgmt.c
@@ -236,11 +236,19 @@ mgmt_getspec_cbk (struct rpc_req *req, struct iovec *iov, int count,
 	int			 ret   = 0;
 	ssize_t			 size = 0;
 	FILE			*tmpfp = NULL;
-	int                      need_retry = 0;
+	int			 need_retry = 0;
 	struct glfs		*fs = NULL;
 
 	frame = myframe;
 	ctx = frame->this->ctx;
+
+	if (!ctx) {
+		gf_log (frame->this->name, GF_LOG_ERROR, "NULL context");
+		errno = EINVAL;
+		ret = -1;
+		goto out;
+	}
+
 	fs = ((xlator_t *)ctx->master)->private;
 
 	if (-1 == req->rpc_status) {
@@ -260,7 +268,7 @@ mgmt_getspec_cbk (struct rpc_req *req, struct iovec *iov, int count,
 		gf_log (frame->this->name, GF_LOG_ERROR,
 			"failed to get the 'volume file' from server");
 		ret = -1;
-                errno = rsp.op_errno;
+		errno = rsp.op_errno;
 		goto out;
 	}
 
@@ -296,7 +304,7 @@ mgmt_getspec_cbk (struct rpc_req *req, struct iovec *iov, int count,
 	*/
 
 	ret = glusterfs_volfile_reconfigure (fs->oldvollen, tmpfp, fs->ctx,
-                                             fs->oldvolfile);
+					     fs->oldvolfile);
 	if (ret == 0) {
 		gf_log ("glusterfsd-mgmt", GF_LOG_DEBUG,
 			"No need to re-load volfile, reconfigure done");
@@ -323,13 +331,13 @@ out:
 	if (rsp.spec)
 		free (rsp.spec);
 
-        // Stop if server is running at an unsupported op-version
-        if (ENOTSUP == ret) {
-                gf_log ("mgmt", GF_LOG_ERROR, "Server is operating at an "
-                        "op-version which is not supported");
-                errno = ENOTSUP;
-                glfs_init_done (fs, -1);
-        }
+	// Stop if server is running at an unsupported op-version
+	if (ENOTSUP == ret) {
+		gf_log ("mgmt", GF_LOG_ERROR, "Server is operating at an "
+			"op-version which is not supported");
+		errno = ENOTSUP;
+		glfs_init_done (fs, -1);
+	}
 
 	if (ret && ctx && !ctx->active) {
 		/* Do it only for the first time */
@@ -339,10 +347,10 @@ out:
 			"failed to fetch volume file (key:%s)",
 			ctx->cmd_args.volfile_id);
 		if (!need_retry) {
-                        if (!errno)
-                                errno = EINVAL;
+			if (!errno)
+				errno = EINVAL;
 			glfs_init_done (fs, -1);
-                }
+		}
 	}
 
 	if (tmpfp)
@@ -420,6 +428,10 @@ mgmt_rpc_notify (struct rpc_clnt *rpc, void *mydata, rpc_clnt_event_t event,
 
 	this = mydata;
 	ctx = this->ctx;
+
+	if (!ctx)
+		goto out;
+
 	fs = ((xlator_t *)ctx->master)->private;
 	cmd_args = &ctx->cmd_args;
 
@@ -434,22 +446,22 @@ mgmt_rpc_notify (struct rpc_clnt *rpc, void *mydata, rpc_clnt_event_t event,
 				"%d connect attempts left",
 				cmd_args->max_connect_attempts);
 			if (0 >= cmd_args->max_connect_attempts) {
-                                errno = ENOTCONN;
+				errno = ENOTCONN;
 				glfs_init_done (fs, -1);
-                        }
+			}
 		}
 		break;
 	case RPC_CLNT_CONNECT:
 		rpc_clnt_set_connected (&((struct rpc_clnt*)ctx->mgmt)->conn);
 
 		ret = glfs_volfile_fetch (fs);
-		if (ret && ctx && (ctx->active == NULL)) {
+		if (ret && (ctx->active == NULL)) {
 			/* Do it only for the first time */
 			/* Exit the process.. there are some wrong options */
 			gf_log ("glfs-mgmt", GF_LOG_ERROR,
 				"failed to fetch volume file (key:%s)",
 				ctx->cmd_args.volfile_id);
-                        errno = EINVAL;
+			errno = EINVAL;
 			glfs_init_done (fs, -1);
 		}
 
@@ -457,7 +469,7 @@ mgmt_rpc_notify (struct rpc_clnt *rpc, void *mydata, rpc_clnt_event_t event,
 	default:
 		break;
 	}
-
+out:
 	return 0;
 }
 
diff --git a/api/src/glfs.c b/api/src/glfs.c
index 174076e390f..ea10fb55c65 100644
--- a/api/src/glfs.c
+++ b/api/src/glfs.c
@@ -589,6 +589,13 @@ glfs_init_async (struct glfs *fs, glfs_init_cbk cbk)
 {
 	int  ret = -1;
 
+	if (!fs || !fs->ctx) {
+		gf_log ("glfs", GF_LOG_ERROR,
+			"fs is not properly initialized.");
+		errno = EINVAL;
+		return ret;
+	}
+
 	fs->init_cbk = cbk;
 
 	ret = glfs_init_common (fs);
@@ -602,6 +609,13 @@ glfs_init (struct glfs *fs)
 {
 	int  ret = -1;
 
+	if (!fs || !fs->ctx) {
+		gf_log ("glfs", GF_LOG_ERROR,
+			"fs is not properly initialized.");
+		errno = EINVAL;
+		return ret;
+	}
+
 	ret = glfs_init_common (fs);
 	if (ret)
 		return ret;