4.9-stable review patch. If anyone has any objections, please let me know.
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From: Tang Junhui tang.junhui@zte.com.cn
[ Upstream commit 7f4fc93d4713394ee8f1cd44c238e046e11b4f15 ]
I attach a back-end device to a cache set, and the cache set is not registered yet, this back-end device did not attach successfully, and no error returned: [root]# echo 87859280-fec6-4bcc-20df7ca8f86b > /sys/block/sde/bcache/attach [root]#
In sysfs_attach(), the return value "v" is initialized to "size" in the beginning, and if no cache set exist in bch_cache_sets, the "v" value would not change any more, and return to sysfs, sysfs regard it as success since the "size" is a positive number.
This patch fixes this issue by assigning "v" with "-ENOENT" in the initialization.
Signed-off-by: Tang Junhui tang.junhui@zte.com.cn Reviewed-by: Michael Lyle mlyle@lyle.org Signed-off-by: Jens Axboe axboe@kernel.dk Signed-off-by: Sasha Levin alexander.levin@microsoft.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/md/bcache/sysfs.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-)
--- a/drivers/md/bcache/sysfs.c +++ b/drivers/md/bcache/sysfs.c @@ -191,7 +191,7 @@ STORE(__cached_dev) { struct cached_dev *dc = container_of(kobj, struct cached_dev, disk.kobj); - ssize_t v = size; + ssize_t v; struct cache_set *c; struct kobj_uevent_env *env;
@@ -268,6 +268,7 @@ STORE(__cached_dev) if (bch_parse_uuid(buf, set_uuid) < 16) return -EINVAL;
+ v = -ENOENT; list_for_each_entry(c, &bch_cache_sets, list) { v = bch_cached_dev_attach(dc, c, set_uuid); if (!v) @@ -275,7 +276,7 @@ STORE(__cached_dev) }
pr_err("Can't attach %s: cache set not found", buf); - size = v; + return v; }
if (attr == &sysfs_detach && dc->disk.c)