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| author | Eric Wheeler <git@linux.ewheeler.net> | 2016-06-17 15:01:54 -0700 |
|---|---|---|
| committer | Eric Wheeler <git@linux.ewheeler.net> | 2016-08-18 20:28:23 -0700 |
| commit | d9dc1702b297ec4a6bb9c0326a70641b322ba886 (patch) | |
| tree | 02965bf0fab5b546fe3d4f822bb3ce240ff36884 /drivers/md | |
| parent | 694d0d0bb2030d2e36df73e2d23d5770511dbc8d (diff) | |
| download | linux-0-day-d9dc1702b297ec4a6bb9c0326a70641b322ba886.tar.gz linux-0-day-d9dc1702b297ec4a6bb9c0326a70641b322ba886.tar.xz | |
bcache: register_bcache(): call blkdev_put() when cache_alloc() fails
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
Diffstat (limited to 'drivers/md')
| -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 95a4ca6ce6fff..6ada14b9a1579 100644 --- a/drivers/md/bcache/super.c +++ b/drivers/md/bcache/super.c @@ -1844,7 +1844,7 @@ 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)); @@ -1861,8 +1861,13 @@ static int register_cache(struct cache_sb *sb, struct page *sb_page, ca->discard = CACHE_DISCARD(&ca->sb); ret = cache_alloc(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"; |