[PATCH V2] Btrfs-progs: subvol_uuid_search: Return error code on memory allocation failure

[PATCH V2] Btrfs-progs: subvol_uuid_search: Return error code on memory allocation failure

[Prasanth K S R]

From: Prasanth K S R <prasanth.ksr@dell.com>

This commit fixes coverity defect CID 1328695.

Signed-off-by: Prasanth K S R <prasanth.ksr@dell.com>
---
 cmds-receive.c | 10 +++++-----
 cmds-send.c    | 18 +++++++++---------
 send-utils.c   | 22 ++++++++++++++++++----
 3 files changed, 32 insertions(+), 18 deletions(-)

diff --git a/cmds-receive.c b/cmds-receive.c
index d0525bf..40f64de 100644
--- a/cmds-receive.c
+++ b/cmds-receive.c
@@ -283,12 +283,12 @@ static int process_snapshot(const char *path, const u8 *uuid, u64 ctransid,
 
 	parent_subvol = subvol_uuid_search(&r->sus, 0, parent_uuid,
 			parent_ctransid, NULL, subvol_search_by_received_uuid);
-	if (!parent_subvol) {
+	if (IS_ERR(parent_subvol)) {
 		parent_subvol = subvol_uuid_search(&r->sus, 0, parent_uuid,
 				parent_ctransid, NULL, subvol_search_by_uuid);
 	}
-	if (!parent_subvol) {
-		ret = -ENOENT;
+	if (IS_ERR(parent_subvol)) {
+		ret = PTR_ERR(parent_subvol);
 		error("cannot find parent subvolume");
 		goto out;
 	}
@@ -744,13 +744,13 @@ static int process_clone(const char *path, u64 offset, u64 len,
 
 	si = subvol_uuid_search(&r->sus, 0, clone_uuid, clone_ctransid, NULL,
 			subvol_search_by_received_uuid);
-	if (!si) {
+	if (IS_ERR(si)) {
 		if (memcmp(clone_uuid, r->cur_subvol.received_uuid,
 				BTRFS_UUID_SIZE) == 0) {
 			/* TODO check generation of extent */
 			subvol_path = strdup(r->cur_subvol_path);
 		} else {
-			ret = -ENOENT;
+			ret = PTR_ERR(si);
 			error("clone: did not find source subvol");
 			goto out;
 		}
diff --git a/cmds-send.c b/cmds-send.c
index 74d0128..b773b40 100644
--- a/cmds-send.c
+++ b/cmds-send.c
@@ -68,8 +68,8 @@ static int get_root_id(struct btrfs_send *s, const char *path, u64 *root_id)
 
 	si = subvol_uuid_search(&s->sus, 0, NULL, 0, path,
 			subvol_search_by_path);
-	if (!si)
-		return -ENOENT;
+	if (IS_ERR(si))
+		return PTR_ERR(si);
 	*root_id = si->root_id;
 	free(si->path);
 	free(si);
@@ -83,8 +83,8 @@ static struct subvol_info *get_parent(struct btrfs_send *s, u64 root_id)
 
 	si_tmp = subvol_uuid_search(&s->sus, root_id, NULL, 0, NULL,
 			subvol_search_by_root_id);
-	if (!si_tmp)
-		return NULL;
+	if (IS_ERR(si_tmp))
+		return si_tmp;
 
 	si = subvol_uuid_search(&s->sus, 0, si_tmp->parent_uuid, 0, NULL,
 			subvol_search_by_uuid);
@@ -104,8 +104,8 @@ static int find_good_parent(struct btrfs_send *s, u64 root_id, u64 *found)
 	int i;
 
 	parent = get_parent(s, root_id);
-	if (!parent) {
-		ret = -ENOENT;
+	if (IS_ERR(parent)) {
+		ret = PTR_ERR(parent);
 		goto out;
 	}
 
@@ -119,7 +119,7 @@ static int find_good_parent(struct btrfs_send *s, u64 root_id, u64 *found)
 
 	for (i = 0; i < s->clone_sources_count; i++) {
 		parent2 = get_parent(s, s->clone_sources[i]);
-		if (!parent2)
+		if (IS_ERR(parent2))
 			continue;
 		if (parent2->root_id != parent->root_id) {
 			free(parent2->path);
@@ -133,8 +133,8 @@ static int find_good_parent(struct btrfs_send *s, u64 root_id, u64 *found)
 		parent2 = subvol_uuid_search(&s->sus, s->clone_sources[i], NULL,
 				0, NULL, subvol_search_by_root_id);
 
-		if (!parent2) {
-			ret = -ENOENT;
+		if (IS_ERR(parent2)) {
+			ret = PTR_ERR(parent2);
 			goto out;
 		}
 		tmp = parent2->ctransid - parent->ctransid;
diff --git a/send-utils.c b/send-utils.c
index a85fa08..87b8559 100644
--- a/send-utils.c
+++ b/send-utils.c
@@ -27,6 +27,7 @@
 #include "send-utils.h"
 #include "ioctl.h"
 #include "btrfs-list.h"
+#include "utils.h"
 
 static int btrfs_subvolid_resolve_sub(int fd, char *path, size_t *path_len,
 				      u64 subvol_id);
@@ -474,6 +475,11 @@ struct subvol_info *subvol_uuid_search(struct subvol_uuid_search *s,
 		goto out;
 
 	info = calloc(1, sizeof(*info));
+	if (!info) {
+		error("Not enough memory");
+		ret = -ENOMEM;
+		goto out;
+	}
 	info->root_id = root_id;
 	memcpy(info->uuid, root_item.uuid, BTRFS_UUID_SIZE);
 	memcpy(info->received_uuid, root_item.received_uuid, BTRFS_UUID_SIZE);
@@ -486,15 +492,23 @@ struct subvol_info *subvol_uuid_search(struct subvol_uuid_search *s,
 		info->path = strdup(path);
 	} else {
 		info->path = malloc(PATH_MAX);
+		if (!info->path) {
+			error("Not enough memory");
+			ret = -ENOMEM;
+			goto out;
+		}
 		ret = btrfs_subvolid_resolve(s->mnt_fd, info->path,
 					     PATH_MAX, root_id);
 	}
 
 out:
-	if (ret && info) {
-		free(info->path);
-		free(info);
-		info = NULL;
+	if (ret) {
+		if (info) {
+			free(info->path);
+			free(info);
+			info = NULL;
+		}
+		return ERR_PTR(ret);
 	}
 
 	return info;
-- 
2.6.6

Re: [PATCH V2] Btrfs-progs: subvol_uuid_search: Return error code on memory allocation failure

[David Sterba]

On Mon, Oct 17, 2016 at 10:07:17AM +0530, Prasanth K S R wrote:
> From: Prasanth K S R <prasanth.ksr@dell.com>
> 
> This commit fixes coverity defect CID 1328695.

The patch does more than that. Please split it into two, one that
handles the memory allocations (the error message is not needed) and
anohter that switches to the IS_ERR/PTR_ERR return type. Thanks.