2019-08-18 10:52:14

by Pan Bian

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

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.

Signed-off-by: Pan Bian <[email protected]>
---
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

2019-08-18 16:28:41

by Bart Van Assche

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

On 8/18/19 3:35 AM, Pan Bian wrote:
> 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.
>
> Signed-off-by: Pan Bian <[email protected]>
> ---
> 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);
>

Also for this patch, please add "Fixes:" and "Cc: stable" tags.

Thanks,

Bart.