[Libguestfs] [PATCH v4 1/3] do_btrfs_qgroup_show: fix a bad return value
We should not use tmp lines buffer as return value,
for lines buffer will be freed.
Signed-off-by: Chen Hanxiao <chenhanxiao(a)cn.fujitsu.com>
---
v4: take advantage of sscanf's '%m'.
v3: fix test case failure
daemon/btrfs.c | 40 ++++++++++++++++++----------------------
1 file changed, 18 insertions(+), 22 deletions(-)
diff --git a/daemon/btrfs.c b/daemon/btrfs.c
index 7b14bac..8d03caa 100644
--- a/daemon/btrfs.c
+++ b/daemon/btrfs.c
@@ -1249,7 +1249,7 @@ do_btrfs_qgroup_show (const char *path)
CLEANUP_FREE char *err = NULL;
CLEANUP_FREE char *out = NULL;
int r;
- char **lines;
+ CLEANUP_FREE_STRING_LIST char **lines = NULL;
path_buf = sysroot_path (path);
if (path_buf == NULL) {
@@ -1275,17 +1275,19 @@ do_btrfs_qgroup_show (const char *path)
if (!lines)
return NULL;
- /* line 0 and 1 are:
+ /* Output of `btrfs qgroup show' is like:
+ *
+ * qgroupid rfer excl
+ * -------- ---- ----
+ * 0/5 9249849344 9249849344
*
- * qgroupid rfer excl
- * -------- ---- ----
*/
size_t nr_qgroups = count_strings (lines) - 2;
guestfs_int_btrfsqgroup_list *ret = NULL;
ret = malloc (sizeof *ret);
if (!ret) {
reply_with_perror ("malloc");
- goto error;
+ return NULL;
}
ret->guestfs_int_btrfsqgroup_list_len = nr_qgroups;
@@ -1293,38 +1295,32 @@ do_btrfs_qgroup_show (const char *path)
calloc (nr_qgroups, sizeof (struct guestfs_int_btrfsqgroup));
if (ret->guestfs_int_btrfsqgroup_list_val == NULL) {
reply_with_perror ("malloc");
- goto error;
+ free (ret);
+ return NULL;
}
for (i = 0; i < nr_qgroups; ++i) {
char *line = lines[i + 2];
struct guestfs_int_btrfsqgroup *this =
&ret->guestfs_int_btrfsqgroup_list_val[i];
- uint64_t dummy1, dummy2;
- char *p;
- if (sscanf (line, "%" SCNu64 "/%" SCNu64 " %" SCNu64
" %" SCNu64,
- &dummy1, &dummy2, &this->btrfsqgroup_rfer,
- &this->btrfsqgroup_excl) != 4) {
+ if (sscanf (line, "%m[0-9/] %" SCNu64 " %" SCNu64,
+ &this->btrfsqgroup_id, &this->btrfsqgroup_rfer,
+ &this->btrfsqgroup_excl) != 3) {
reply_with_error ("cannot parse output of qgroup show command: %s",
line);
goto error;
}
- p = strchr(line, ' ');
- if (!p) {
- reply_with_error ("truncated line: %s", line);
- goto error;
- }
- *p = '\0';
- this->btrfsqgroup_id = line;
}
- free (lines);
return ret;
error:
- free_stringslen (lines, nr_qgroups + 2);
- if (ret)
- free (ret->guestfs_int_btrfsqgroup_list_val);
+ for (i = 0; i < nr_qgroups; ++i) {
+ struct guestfs_int_btrfsqgroup *this =
+ &ret->guestfs_int_btrfsqgroup_list_val[i];
+ free (this->btrfsqgroup_id);
+ }
+ free (ret->guestfs_int_btrfsqgroup_list_val);
free (ret);
return NULL;
--
2.1.0