From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jens Axboe Subject: Re: [PATCH AUTOSEL 5.3 15/71] rbd: fix response length parameter for encoded strings Date: Tue, 8 Oct 2019 21:45:18 -0600 Message-ID: References: <20191001163922.14735-1-sashal@kernel.org> <20191001163922.14735-15-sashal@kernel.org> <20191008212944.GD1396@sasha-vm> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20191008212944.GD1396@sasha-vm> Content-Language: en-US Sender: linux-kernel-owner@vger.kernel.org To: Sasha Levin , Ilya Dryomov Cc: LKML , stable@vger.kernel.org, Dongsheng Yang , Ceph Development , linux-block List-Id: ceph-devel.vger.kernel.org On 10/8/19 3:29 PM, Sasha Levin wrote: > On Tue, Oct 01, 2019 at 07:15:49PM +0200, Ilya Dryomov wrote: >> On Tue, Oct 1, 2019 at 6:39 PM Sasha Levin wrote: >>> >>> From: Dongsheng Yang >>> >>> [ Upstream commit 5435d2069503e2aa89c34a94154f4f2fa4a0c9c4 ] >>> >>> rbd_dev_image_id() allocates space for length but passes a smaller >>> value to rbd_obj_method_sync(). rbd_dev_v2_object_prefix() doesn't >>> allocate space for length. Fix both to be consistent. >>> >>> Signed-off-by: Dongsheng Yang >>> Reviewed-by: Ilya Dryomov >>> Signed-off-by: Ilya Dryomov >>> Signed-off-by: Sasha Levin >>> --- >>> drivers/block/rbd.c | 10 ++++++---- >>> 1 file changed, 6 insertions(+), 4 deletions(-) >>> >>> diff --git a/drivers/block/rbd.c b/drivers/block/rbd.c >>> index c8fb886aebd4e..69db7385c8df5 100644 >>> --- a/drivers/block/rbd.c >>> +++ b/drivers/block/rbd.c >>> @@ -5669,17 +5669,20 @@ static int rbd_dev_v2_image_size(struct rbd_device *rbd_dev) >>> >>> static int rbd_dev_v2_object_prefix(struct rbd_device *rbd_dev) >>> { >>> + size_t size; >>> void *reply_buf; >>> int ret; >>> void *p; >>> >>> - reply_buf = kzalloc(RBD_OBJ_PREFIX_LEN_MAX, GFP_KERNEL); >>> + /* Response will be an encoded string, which includes a length */ >>> + size = sizeof(__le32) + RBD_OBJ_PREFIX_LEN_MAX; >>> + reply_buf = kzalloc(size, GFP_KERNEL); >>> if (!reply_buf) >>> return -ENOMEM; >>> >>> ret = rbd_obj_method_sync(rbd_dev, &rbd_dev->header_oid, >>> &rbd_dev->header_oloc, "get_object_prefix", >>> - NULL, 0, reply_buf, RBD_OBJ_PREFIX_LEN_MAX); >>> + NULL, 0, reply_buf, size); >>> dout("%s: rbd_obj_method_sync returned %d\n", __func__, ret); >>> if (ret < 0) >>> goto out; >>> @@ -6696,7 +6699,6 @@ static int rbd_dev_image_id(struct rbd_device *rbd_dev) >>> dout("rbd id object name is %s\n", oid.name); >>> >>> /* Response will be an encoded string, which includes a length */ >>> - >>> size = sizeof (__le32) + RBD_IMAGE_ID_LEN_MAX; >>> response = kzalloc(size, GFP_NOIO); >>> if (!response) { >>> @@ -6708,7 +6710,7 @@ static int rbd_dev_image_id(struct rbd_device *rbd_dev) >>> >>> ret = rbd_obj_method_sync(rbd_dev, &oid, &rbd_dev->header_oloc, >>> "get_id", NULL, 0, >>> - response, RBD_IMAGE_ID_LEN_MAX); >>> + response, size); >>> dout("%s: rbd_obj_method_sync returned %d\n", __func__, ret); >>> if (ret == -ENOENT) { >>> image_id = kstrdup("", GFP_KERNEL); >> >> Hi Sasha, >> >> This patch just made things consistent, there was no bug here. I don't >> think it should be backported. > > I'll drop it, thanks! How did it even get picked up, it's not marked for stable? -- Jens Axboe