From: Joe Perches <joe@perches.com>
To: "Michael S. Tsirkin" <mst@redhat.com>,
Bartosz Golaszewski <brgl@bgdev.pl>
Cc: alsa-devel@alsa-project.org, kvm@vger.kernel.org,
"David Airlie" <airlied@linux.ie>,
"Gustavo Padovan" <gustavo@padovan.org>,
dri-devel@lists.freedesktop.org,
"Jaroslav Kysela" <perex@perex.cz>,
linux-mm@kvack.org, "Christoph Lameter" <cl@linux.com>,
"Mauro Carvalho Chehab" <mchehab@kernel.org>,
"Bartosz Golaszewski" <bgolaszewski@baylibre.com>,
"Alexander Shishkin" <alexander.shishkin@linux.intel.com>,
"David Rientjes" <rientjes@google.com>,
virtualization@lists.linux-foundation.org,
"Jason Wang" <jasowang@redhat.com>,
linux-media@vger.kernel.org, "Robert Richter" <rric@kernel.org>,
"Thomas Zimmermann" <tzimmermann@suse.de>,
linaro-mm-sig@lists.linaro.org, linux-gpio@vger.kernel.org,
"Borislav Petkov" <bp@alien8.de>,
"Andy Shevchenko" <andriy.shevchenko@linux.intel.com>,
"Joonsoo Kim" <iamjoonsoo.kim@lge.com>,
linux-edac@vger.kernel.org, "Tony Luck" <tony.luck@intel.com>,
netdev@vger.kernel.org, "Takashi Iwai" <tiwai@suse.com>,
linux-kernel@vger.kernel.org, "Pekka Enberg" <penberg@kernel.org>,
"James Morse" <james.morse@arm.com>,
"Andrew Morton" <akpm@linux-foundation.org>,
"Christian König" <christian.koenig@amd.com>
Subject: Re: [PATCH 3/8] vhost: vringh: use krealloc_array()
Date: Tue, 27 Oct 2020 09:50:36 -0700 [thread overview]
Message-ID: <685d850347a1191bba8ba7766fc409b140d18f03.camel@perches.com> (raw)
In-Reply-To: <20201027112607-mutt-send-email-mst@kernel.org>
On Tue, 2020-10-27 at 11:28 -0400, Michael S. Tsirkin wrote:
> On Tue, Oct 27, 2020 at 01:17:20PM +0100, Bartosz Golaszewski wrote:
> > From: Bartosz Golaszewski <bgolaszewski@baylibre.com>
> >
> > Use the helper that checks for overflows internally instead of manually
> > calculating the size of the new array.
> >
> > Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
>
> No problem with the patch, it does introduce some symmetry in the code.
Perhaps more symmetry by using kmemdup
---
drivers/vhost/vringh.c | 23 ++++++++++-------------
1 file changed, 10 insertions(+), 13 deletions(-)
diff --git a/drivers/vhost/vringh.c b/drivers/vhost/vringh.c
index 8bd8b403f087..99222a3651cd 100644
--- a/drivers/vhost/vringh.c
+++ b/drivers/vhost/vringh.c
@@ -191,26 +191,23 @@ static int move_to_indirect(const struct vringh *vrh,
static int resize_iovec(struct vringh_kiov *iov, gfp_t gfp)
{
struct kvec *new;
- unsigned int flag, new_num = (iov->max_num & ~VRINGH_IOV_ALLOCATED) * 2;
+ size_t new_num = (iov->max_num & ~VRINGH_IOV_ALLOCATED) * 2;
+ size_t size;
if (new_num < 8)
new_num = 8;
- flag = (iov->max_num & VRINGH_IOV_ALLOCATED);
- if (flag)
- new = krealloc(iov->iov, new_num * sizeof(struct iovec), gfp);
- else {
- new = kmalloc_array(new_num, sizeof(struct iovec), gfp);
- if (new) {
- memcpy(new, iov->iov,
- iov->max_num * sizeof(struct iovec));
- flag = VRINGH_IOV_ALLOCATED;
- }
- }
+ if (unlikely(check_mul_overflow(new_num, sizeof(struct iovec), &size)))
+ return -ENOMEM;
+
+ if (iov->max_num & VRINGH_IOV_ALLOCATED)
+ new = krealloc(iov->iov, size, gfp);
+ else
+ new = kmemdup(iov->iov, size, gfp);
if (!new)
return -ENOMEM;
iov->iov = new;
- iov->max_num = (new_num | flag);
+ iov->max_num = new_num | VRINGH_IOV_ALLOCATED;
return 0;
}
_______________________________________________
dri-devel mailing list
dri-devel@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/dri-devel
next prev parent reply other threads:[~2020-10-27 16:50 UTC|newest]
Thread overview: 21+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-10-27 12:17 [PATCH 0/8] slab: provide and use krealloc_array() Bartosz Golaszewski
2020-10-27 12:17 ` [PATCH 1/8] mm: slab: provide krealloc_array() Bartosz Golaszewski
2020-10-27 18:20 ` Vlastimil Babka
2020-10-28 8:47 ` Mike Rapoport
2020-10-27 12:17 ` [PATCH 2/8] ALSA: pcm: use krealloc_array() Bartosz Golaszewski
2020-10-27 12:39 ` Takashi Iwai
2020-10-27 12:17 ` [PATCH 3/8] vhost: vringh: " Bartosz Golaszewski
2020-10-27 15:28 ` Michael S. Tsirkin
2020-10-27 16:50 ` Joe Perches [this message]
2020-10-27 16:58 ` Bartosz Golaszewski
2020-10-27 17:08 ` Joe Perches
2020-10-27 18:00 ` Bartosz Golaszewski
2020-10-27 12:17 ` [PATCH 4/8] pinctrl: " Bartosz Golaszewski
2020-10-27 12:17 ` [PATCH 5/8] edac: ghes: " Bartosz Golaszewski
2020-10-27 18:25 ` Borislav Petkov
2020-10-27 12:17 ` [PATCH 6/8] drm: atomic: " Bartosz Golaszewski
2020-10-27 19:19 ` Daniel Vetter
2020-10-27 12:17 ` [PATCH 7/8] hwtracing: intel: " Bartosz Golaszewski
2020-10-27 12:17 ` [PATCH 8/8] dma-buf: " Bartosz Golaszewski
2020-10-27 12:21 ` Christian König
2020-11-05 10:52 ` [PATCH 0/8] slab: provide and " Linus Walleij
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