We should not use temporary lines buffer as return value, for lines buffer will be freed. Signed-off-by: Chen Hanxiao <chenhanxiao(a)cn.fujitsu.com&gt; --- v5: modify according to Pino's comments v4: take advantage of sscanf's '%m'. v3: fix test case failure daemon/btrfs.c | 34 ++++++++++++++-------------------- 1 file changed, 14 insertions(+), 20 deletions(-) diff --git a/daemon/btrfs.c b/daemon/btrfs.c index 2f875ae..715d7d2 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; @@ -1300,31 +1302,23 @@ do_btrfs_qgroup_show (const char *path) 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) + if (ret->guestfs_int_btrfsqgroup_list_val) { + for (i = 0; i < nr_qgroups; ++i) + free (ret->guestfs_int_btrfsqgroup_list_val[i].btrfsqgroup_id); free (ret->guestfs_int_btrfsqgroup_list_val); + } free (ret); return NULL; -- 2.1.0