diff options
| author | Bryn M. Reeves <bmr@redhat.com> | 2016-09-27 14:35:22 +0100 |
|---|---|---|
| committer | Bryn M. Reeves <bmr@redhat.com> | 2016-09-27 14:46:00 +0100 |
| commit | 6ec8854fdb051b092d5e262dc6c6d4c2ea075cd1 (patch) | |
| tree | 74ec23e82ac98639b425f52f5235644ae6f13365 | |
| parent | 0a480c5c52bd34a1eb8337d59a7f4cc60317d2b1 (diff) | |
| download | lvm2-6ec8854fdb051b092d5e262dc6c6d4c2ea075cd1.tar.gz | |
libdm: fix stats walk compatibility with older dmsetup
The current dmsetup.c handles DR_STATS and DR_STATS_META reports
separately in _display_info_cols(), meaning that the stats walk
functions are never called for these report types.
Versions before v2.02.159 have a loop using dm_stats_walk_do() and
dm_stats_walk_while(), that executes once for non-stats reports,
and once per region, or area, for DR_STATS/DR_STATS_META reports.
This older behaviour relies on the documented behaviour that the
walk functions will accept a NULL pointer as the struct dm_stats*
argument.
This was broken by commit f1f2df7b: the NULL test on dms and
dms->regions were incorrectly moved from the dm_stats_walk_end()
wrapper to the internal '_stats_walk_end()' helper.
Since the pointer is dereferenced in between these points, using
an older dmsetup with current libdm results in a segfault when
running a non-stats report:
# dmsetup info -c vg00/lvol0
Segmentation fault (core dumped)
Restore the NULL checks to the wrapper function as intended.
| -rw-r--r-- | WHATS_NEW_DM | 1 | ||||
| -rw-r--r-- | libdm/libdm-stats.c | 6 |
2 files changed, 4 insertions, 3 deletions
diff --git a/WHATS_NEW_DM b/WHATS_NEW_DM index 29dbccc78..b048f7a98 100644 --- a/WHATS_NEW_DM +++ b/WHATS_NEW_DM @@ -1,5 +1,6 @@ Version 1.02.136 - ====================================== + Fix stats walk segfault with dmsetup older than v1.02.129 Version 1.02.135 - 26th September 2016 ====================================== diff --git a/libdm/libdm-stats.c b/libdm/libdm-stats.c index ffd349cf9..75e014435 100644 --- a/libdm/libdm-stats.c +++ b/libdm/libdm-stats.c @@ -1526,9 +1526,6 @@ static void _stats_walk_end_areas(const struct dm_stats *dms, uint64_t *flags, static int _stats_walk_end(const struct dm_stats *dms, uint64_t *flags, uint64_t *cur_r, uint64_t *cur_a, uint64_t *cur_g) { - if (!dms || !dms->regions) - return 1; - if (*flags & DM_STATS_WALK_AREA) { _stats_walk_end_areas(dms, flags, cur_r, cur_a, cur_g); goto out; @@ -1553,6 +1550,9 @@ out: int dm_stats_walk_end(struct dm_stats *dms) { + if (!dms || !dms->regions) + return 1; + if (_stats_walk_end(dms, &dms->cur_flags, &dms->cur_region, &dms->cur_area, &dms->cur_group)) { |