Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67;
IronPort-SDR: aKXmKjVRUkKE8iwJNshlIPLRqo6g+AtE8o9yo0fAmaj0VEFHYz1u3hRJoPhJTRPwBavB8x+1Fe
 kVdQCqU6xfBXK+CJxcWXtmkZ15SZaDd8qWm+HnA7JtuFFhnXnTrS9arEn8VlfzO4fghjj151T7
 beLltUwUNXhgNhskCYgRRkr7RCIBOFVwaqNUPDIZBuB14MsuSe3C9/tRKlFcqPADKwm/supzFY
 dIPS+wguCW6Q7Y716qLtuoI6/osLlmdu8EOAacseQ1mor0EJLhoIXJQbkumQGzzxWaIvSgSayN
 BaM=
IronPort-SDR: WEUnwhIVQYIKrP2/Kxc7b0dvSWUALKTptRDdbg6PgBcjfKm+SHNhakENdN+ZMCfHp8M9M5K9Qm
 0u/F+5ot23YO9s7ewqEUcyOv9VojB+zTASL7LGRqluIBv4hdZJ+RNFRjEh4agVJSJYC7E38qOQ
 8CiuMNqFHztXRJHvGhgxGE4mVnB9A2Wjv74fvWS/r4+SjjenGr9Qw6luSuoPNCwMN31NnospxN
 Omv8PdcZEIa6lYlN1pyrx8/OeXAK8PKcDI7zrkG9DpudOgh87aOWpOi8Er0NQ9Q+uTgVkH57ah
 My2mqd3hjg9qtKINaqL698UX
IronPort-SDR: 2+0hE7nYdSw2DI7ET7vzyzVgDLnT6I53JDmEJH5Nsy1KZSawtvq8njkWFl9HdZra7trNIVvI9+
 +C3jml8b1i7kk66snO1rJW0Yl6flU2QlI60KsHSx9tad1F7Ls6eiIwTonTvkZFRABdIm7iXkCT
 P4qkpuriPOl+U1UUmICciYWBWYGIFFp7jwfuppSvxWFB86hsMWVYpUlBX0QhqvxfmBZexH07Vb
 AtXjBp9ii+mFLhHRWztk6f9NNxjx5ozr6XIrvjCdyH49tnHx9XC7LLjcEviRXPwCZTpiYRQJoW
 DC4=
WDCIronportException: Internal
Date:   Wed, 4 Dec 2019 18:56:15 +0900
From:   Naohiro Aota <naohiro.aota@wdc.com>
To:     Keita Suzuki <keitasuzuki.park@sslab.ics.keio.ac.jp>
Cc:     Jens Axboe <axboe@kernel.dk>, linux-block@vger.kernel.org,
        linux-kernel@vger.kernel.org,
        takafumi.kubota1012@sslab.ics.keio.ac.jp
Subject: Re: [PATCH] block/genhd: Fix memory leak in error path of
 __alloc_disk_node()
Message-ID: <20191204095615.m3bgg276re3qlzzm@naota>
References: <20191127024057.5827-1-keitasuzuki.park@sslab.ics.keio.ac.jp>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii; format=flowed
Content-Disposition: inline
In-Reply-To: <20191127024057.5827-1-keitasuzuki.park@sslab.ics.keio.ac.jp>
Sender: linux-kernel-owner@vger.kernel.org
Precedence: bulk

Looks good,
Reviewed-by: Naohiro Aota <naohiro.aota@wdc.com>

I think you can also add:

Fixes: 6c71013ecb7e ("block: partition: convert percpu ref")

On Wed, Nov 27, 2019 at 02:40:57AM +0000, Keita Suzuki wrote:
>'disk->part_tbl' is malloced in disk_expand_part_tbl() and should be
>freed before leaving from the error handling cases. However, current code
>does not free this, causing a memory leak. Add disk_replace_part_tbl()
>before freeing 'disk'.
>
>I have tested this by randomly causing failures to the target code,
>and verified on kmemleak that this memory leak does occur.
>
>unreferenced object 0xffff888006dad500 (size 64):
>  comm "systemd-udevd", pid 116, jiffies 4294895558 (age 121.716s)
>  hex dump (first 32 bytes):
>    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
>    01 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
>  backtrace:
>    [<00000000eec79bf3>] disk_expand_part_tbl+0xab/0x170
>    [<00000000624e7d03>] __alloc_disk_node+0xb1/0x1c0
>    [<00000000ca3f4185>] 0xffffffffc01b8584
>    [<000000006f88a6ee>] do_one_initcall+0x8b/0x2a4
>    [<0000000016058199>] do_init_module+0xfd/0x380
>    [<00000000b6fde336>] load_module+0x3fae/0x4240
>    [<00000000c523d013>] __do_sys_finit_module+0x11a/0x1b0
>    [<00000000f07bba26>] do_syscall_64+0x6d/0x1e0
>    [<00000000979467fd>] entry_SYSCALL_64_after_hwframe+0x44/0xa9
>
>Signed-off-by: Keita Suzuki <keitasuzuki.park@sslab.ics.keio.ac.jp>
>---
> block/genhd.c | 1 +
> 1 file changed, 1 insertion(+)
>
>diff --git a/block/genhd.c b/block/genhd.c
>index ff6268970ddc..8c4b63d7f507 100644
>--- a/block/genhd.c
>+++ b/block/genhd.c
>@@ -1504,6 +1504,7 @@ struct gendisk *__alloc_disk_node(int minors, int node_id)
> 		 */
> 		seqcount_init(&disk->part0.nr_sects_seq);
> 		if (hd_ref_init(&disk->part0)) {
>+			disk_replace_part_tbl(disk, NULL);
> 			hd_free_part(&disk->part0);
> 			kfree(disk);
> 			return NULL;
>-- 
>2.17.1
>