> -----Original Message----- > From: Dan Carpenter [mailto:dan.carpenter@xxxxxxxxxx] > Sent: Tuesday, June 23, 2020 6:28 AM > To: Colin King <colin.king@xxxxxxxxxxxxx> > Cc: Seth Jennings <sjenning@xxxxxxxxxx>; Dan Streetman > <ddstreet@xxxxxxxx>; Vitaly Wool <vitaly.wool@xxxxxxxxxxxx>; Andrew > Morton <akpm@xxxxxxxxxxxxxxxxxxxx>; Song Bao Hua (Barry Song) > <song.bao.hua@xxxxxxxxxxxxx>; Stephen Rothwell <sfr@xxxxxxxxxxxxxxxx>; > linux-mm@xxxxxxxxx; kernel-janitors@xxxxxxxxxxxxxxx; > linux-kernel@xxxxxxxxxxxxxxx > Subject: Re: [PATCH][next] mm/zswap: fix a couple of memory leaks and > rework kzalloc failure check > > On Mon, Jun 22, 2020 at 04:35:46PM +0100, Colin King wrote: > > From: Colin Ian King <colin.king@xxxxxxxxxxxxx> > > > > 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@xxxxxxxxxxxxx> Colin, thanks for your patch. I am sorry I did the same thing with you here: https://lkml.org/lkml/2020/6/22/347 > > --- > > 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
