From: Dan Carpenter <dan.carpenter@oracle.com>
To: Colin King <colin.king@canonical.com>
Cc: Seth Jennings <sjenning@redhat.com>,
Dan Streetman <ddstreet@ieee.org>,
Vitaly Wool <vitaly.wool@konsulko.com>,
Andrew Morton <akpm@linux-foundation.org>,
Barry Song <song.bao.hua@hisilicon.com>,
Stephen Rothwell <sfr@canb.auug.org.au>,
linux-mm@kvack.org, kernel-janitors@vger.kernel.org,
linux-kernel@vger.kernel.org
Subject: Re: [PATCH][next] mm/zswap: fix a couple of memory leaks and rework kzalloc failure check
Date: Mon, 22 Jun 2020 18:28:17 +0000 [thread overview]
Message-ID: <20200622182816.GF4151@kadam> (raw)
In-Reply-To: <20200622153546.49880-1-colin.king@canonical.com>
On Mon, Jun 22, 2020 at 04:35:46PM +0100, Colin King wrote:
> From: Colin Ian King <colin.king@canonical.com>
>
> kzalloc failures return NULL on out of memory errors, so replace the
> IS_ERR_OR_NULL check with the usual null pointer check. Fix two memory
> leaks with on acomp and acomp_ctx by ensuring these objects are free'd
> on the error return path.
>
> Addresses-Coverity: ("Resource leak")
> Fixes: d4f86abd6e35 ("mm/zswap: move to use crypto_acomp API for hardware acceleration")
> Signed-off-by: Colin Ian King <colin.king@canonical.com>
> ---
> mm/zswap.c | 16 +++++++++++-----
> 1 file changed, 11 insertions(+), 5 deletions(-)
>
> diff --git a/mm/zswap.c b/mm/zswap.c
> index 0d914ba6b4a0..14839cbac7ff 100644
> --- a/mm/zswap.c
> +++ b/mm/zswap.c
> @@ -433,23 +433,23 @@ static int zswap_cpu_comp_prepare(unsigned int cpu, struct hlist_node *node)
> return 0;
>
> acomp_ctx = kzalloc(sizeof(*acomp_ctx), GFP_KERNEL);
> - if (IS_ERR_OR_NULL(acomp_ctx)) {
> + if (!acomp_ctx) {
> pr_err("Could not initialize acomp_ctx\n");
> return -ENOMEM;
> }
> acomp = crypto_alloc_acomp(pool->tfm_name, 0, 0);
> - if (IS_ERR_OR_NULL(acomp)) {
> + if (!acomp) {
This should be IS_ERR(acomp). Please preserve the error code.
> pr_err("could not alloc crypto acomp %s : %ld\n",
> pool->tfm_name, PTR_ERR(acomp));
> - return -ENOMEM;
> + goto free_acomp_ctx;
> }
> acomp_ctx->acomp = acomp;
>
> req = acomp_request_alloc(acomp_ctx->acomp);
> - if (IS_ERR_OR_NULL(req)) {
> + if (!req) {
> pr_err("could not alloc crypto acomp %s : %ld\n",
> pool->tfm_name, PTR_ERR(acomp));
> - return -ENOMEM;
> + goto free_acomp;
> }
> acomp_ctx->req = req;
>
> @@ -462,6 +462,12 @@ static int zswap_cpu_comp_prepare(unsigned int cpu, struct hlist_node *node)
> *per_cpu_ptr(pool->acomp_ctx, cpu) = acomp_ctx;
>
> return 0;
> +
> +free_acomp:
> + kfree(acomp);
The kfree() isn't correct. It needs to be:
crypto_free_acomp(acomp);
> +free_acomp_ctx:
> + kfree(acomp_ctx);
> + return -ENOMEM;
regards,
dan carpenter
next prev parent reply other threads:[~2020-06-22 18:28 UTC|newest]
Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-06-22 15:35 [PATCH][next] mm/zswap: fix a couple of memory leaks and rework kzalloc failure check Colin King
2020-06-22 18:28 ` Dan Carpenter [this message]
2020-06-22 19:55 ` Song Bao Hua (Barry Song)
2020-06-23 11:12 ` Colin Ian King
2020-06-23 14:02 ` Vitaly Wool
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