[PATCH V2] block/bio-integrity: fix mismatched alloc free

[Pan Bian]

The function kmalloc rather than mempool_alloc is called to allocate
memory when the memory pool is unavailable. However, mempool_alloc is
used to release the memory chunck in both cases when error occurs. This
patch fixes the bug.

Fixes: 9f060e2231c ("block: Convert integrity to bvec_alloc_bs()")
Signed-off-by: Pan Bian <bianpan2016@xxxxxxx>
Cc: stable@xxxxxxxxxxxxxxx
---
V2: add Fixes and CC tags
---
 block/bio-integrity.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/block/bio-integrity.c b/block/bio-integrity.c
index fb95dbb..011dfc8 100644
--- a/block/bio-integrity.c
+++ b/block/bio-integrity.c
@@ -75,7 +75,10 @@ struct bio_integrity_payload *bio_integrity_alloc(struct bio *bio,
 
 	return bip;
 err:
-	mempool_free(bip, &bs->bio_integrity_pool);
+	if (!bs || !mempool_initialized(&bs->bio_integrity_pool))
+		kfree(bip);
+	else
+		mempool_free(bip, &bs->bio_integrity_pool);
 	return ERR_PTR(-ENOMEM);
 }
 EXPORT_SYMBOL(bio_integrity_alloc);
-- 
2.7.4