diff options
author | Jiasheng Jiang <jiasheng@iscas.ac.cn> | 2023-03-16 14:55:06 +0800 |
---|---|---|
committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2023-04-05 11:16:41 +0200 |
commit | 4a32a9a818a895671bd43e0c40351e60e4e9140b (patch) | |
tree | b7d5ba38360b6f459a4c224d728fdbf7c780db1d /drivers/md | |
parent | f8cbad984b1601435d087125ac760d3cae90213a (diff) |
dm stats: check for and propagate alloc_percpu failure
commit d3aa3e060c4a80827eb801fc448debc9daa7c46b upstream.
Check alloc_precpu()'s return value and return an error from
dm_stats_init() if it fails. Update alloc_dev() to fail if
dm_stats_init() does.
Otherwise, a NULL pointer dereference will occur in dm_stats_cleanup()
even if dm-stats isn't being actively used.
Fixes: fd2ed4d25270 ("dm: add statistics support")
Cc: stable@vger.kernel.org
Signed-off-by: Jiasheng Jiang <jiasheng@iscas.ac.cn>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/md')
-rw-r--r-- | drivers/md/dm-stats.c | 7 | ||||
-rw-r--r-- | drivers/md/dm-stats.h | 2 | ||||
-rw-r--r-- | drivers/md/dm.c | 4 |
3 files changed, 10 insertions, 3 deletions
diff --git a/drivers/md/dm-stats.c b/drivers/md/dm-stats.c index ce6d3bce1b7b..0f42f4a7f382 100644 --- a/drivers/md/dm-stats.c +++ b/drivers/md/dm-stats.c @@ -188,7 +188,7 @@ static int dm_stat_in_flight(struct dm_stat_shared *shared) atomic_read(&shared->in_flight[WRITE]); } -void dm_stats_init(struct dm_stats *stats) +int dm_stats_init(struct dm_stats *stats) { int cpu; struct dm_stats_last_position *last; @@ -196,11 +196,16 @@ void dm_stats_init(struct dm_stats *stats) mutex_init(&stats->mutex); INIT_LIST_HEAD(&stats->list); stats->last = alloc_percpu(struct dm_stats_last_position); + if (!stats->last) + return -ENOMEM; + for_each_possible_cpu(cpu) { last = per_cpu_ptr(stats->last, cpu); last->last_sector = (sector_t)ULLONG_MAX; last->last_rw = UINT_MAX; } + + return 0; } void dm_stats_cleanup(struct dm_stats *stats) diff --git a/drivers/md/dm-stats.h b/drivers/md/dm-stats.h index 2ddfae678f32..dcac11fce03b 100644 --- a/drivers/md/dm-stats.h +++ b/drivers/md/dm-stats.h @@ -22,7 +22,7 @@ struct dm_stats_aux { unsigned long long duration_ns; }; -void dm_stats_init(struct dm_stats *st); +int dm_stats_init(struct dm_stats *st); void dm_stats_cleanup(struct dm_stats *st); struct mapped_device; diff --git a/drivers/md/dm.c b/drivers/md/dm.c index b58ff1a0fda7..771167ee552c 100644 --- a/drivers/md/dm.c +++ b/drivers/md/dm.c @@ -1994,7 +1994,9 @@ static struct mapped_device *alloc_dev(int minor) if (!md->bdev) goto bad; - dm_stats_init(&md->stats); + r = dm_stats_init(&md->stats); + if (r < 0) + goto bad; /* Populate the mapping, nobody knows we exist yet */ spin_lock(&_minor_lock); |