From ece841abbed2da71fa10710c687c9ce9efb6bf69 Mon Sep 17 00:00:00 2001
From: Justin Tee <justin.tee@broadcom.com>
Date: Thu, 5 Dec 2019 10:09:01 +0800
Subject: [PATCH] block: fix memleak of bio integrity data
Git-commit: ece841abbed2da71fa10710c687c9ce9efb6bf69
Patch-mainline: v5.5-rc1
References: git fixes (block drivers)

7c20f11680a4 ("bio-integrity: stop abusing bi_end_io") moves
bio_integrity_free from bio_uninit() to bio_integrity_verify_fn()
and bio_endio(). This way looks wrong because bio may be freed
without calling bio_endio(), for example, blk_rq_unprep_clone() is
called from dm_mq_queue_rq() when the underlying queue of dm-mpath
is busy.

So memory leak of bio integrity data is caused by commit 7c20f11680a4.

Fixes this issue by re-adding bio_integrity_free() to bio_uninit().

Fixes: 7c20f11680a4 ("bio-integrity: stop abusing bi_end_io")
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by Justin Tee <justin.tee@broadcom.com>

Add commit log, and simplify/fix the original patch wroten by Justin.

(Coly Li: rebased for fixes/linux-4.12 code base)

Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Coly Li <colyli@suse.de>

---
 block/bio-integrity.c |    2 +-
 block/blk.h           |    4 ++++
 2 files changed, 5 insertions(+), 1 deletion(-)

--- a/block/bio-integrity.c
+++ b/block/bio-integrity.c
@@ -102,7 +102,7 @@ EXPORT_SYMBOL(bio_integrity_alloc);
  * Description: Used to free the integrity portion of a bio. Usually
  * called from bio_free().
  */
-static void bio_integrity_free(struct bio *bio)
+void bio_integrity_free(struct bio *bio)
 {
 	struct bio_integrity_payload *bip = bio_integrity(bio);
 	struct bio_set *bs = bio->bi_pool;
--- a/block/blk.h
+++ b/block/blk.h
@@ -83,6 +83,7 @@ static inline void blk_queue_enter_live(
 #ifdef CONFIG_BLK_DEV_INTEGRITY
 void blk_flush_integrity(void);
 bool __bio_integrity_endio(struct bio *);
+void bio_integrity_free(struct bio *bio);
 static inline bool bio_integrity_endio(struct bio *bio)
 {
 	if (bio_integrity(bio))
@@ -97,6 +98,9 @@ static inline bool bio_integrity_endio(s
 {
 	return true;
 }
+static inline void bio_integrity_free(struct bio *bio)
+{
+}
 #endif /* CONFIG_BLK_DEV_INTEGRITY */
 
 void blk_timeout_work(struct work_struct *work);