diff options
author | Eric Wheeler <git@linux.ewheeler.net> | 2016-06-17 15:01:54 -0700 |
---|---|---|
committer | Sasha Levin <alexander.levin@verizon.com> | 2016-08-31 19:21:09 -0400 |
commit | 220360d6ac0e1ef0cf364028c26f44ac99c306c4 (patch) | |
tree | f1d4706ca5fa41c52a2e9c0cdfee6c64dc352693 | |
parent | 35b8f91bf61afc5764e739e718651afba580f9e8 (diff) |
bcache: register_bcache(): call blkdev_put() when cache_alloc() fails
[ Upstream commit d9dc1702b297ec4a6bb9c0326a70641b322ba886 ]
register_cache() is supposed to return an error string on error so that
register_bcache() will will blkdev_put and cleanup other user counters,
but it does not set 'char *err' when cache_alloc() fails (eg, due to
memory pressure) and thus register_bcache() performs no cleanup.
register_bcache() <----------\ <- no jump to err_close, no blkdev_put()
| |
+->register_cache() | <- fails to set char *err
| |
+->cache_alloc() ---/ <- returns error
This patch sets `char *err` for this failure case so that register_cache()
will cause register_bcache() to correctly jump to err_close and do
cleanup. This was tested under OOM conditions that triggered the bug.
Signed-off-by: Eric Wheeler <bcache@linux.ewheeler.net>
Cc: Kent Overstreet <kent.overstreet@gmail.com>
Cc: stable@vger.kernel.org
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
-rw-r--r-- | drivers/md/bcache/super.c | 9 |
1 files changed, 7 insertions, 2 deletions
diff --git a/drivers/md/bcache/super.c b/drivers/md/bcache/super.c index 2a102834c2ee..1111ce96decf 100644 --- a/drivers/md/bcache/super.c +++ b/drivers/md/bcache/super.c @@ -1876,7 +1876,7 @@ static int register_cache(struct cache_sb *sb, struct page *sb_page, struct block_device *bdev, struct cache *ca) { char name[BDEVNAME_SIZE]; - const char *err = NULL; + const char *err = NULL; /* must be set for any error case */ int ret = 0; memcpy(&ca->sb, sb, sizeof(struct cache_sb)); @@ -1893,8 +1893,13 @@ static int register_cache(struct cache_sb *sb, struct page *sb_page, ca->discard = CACHE_DISCARD(&ca->sb); ret = cache_alloc(sb, ca); - if (ret != 0) + if (ret != 0) { + if (ret == -ENOMEM) + err = "cache_alloc(): -ENOMEM"; + else + err = "cache_alloc(): unknown error"; goto err; + } if (kobject_add(&ca->kobj, &part_to_dev(bdev->bd_part)->kobj, "bcache")) { err = "error calling kobject_add"; |