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Date:   Wed, 30 Mar 2022 07:30:25 +0300
From:   Dan Carpenter <dan.carpenter@oracle.com>
To:     "Fabio M. De Francesco" <fmdefrancesco@gmail.com>
Cc:     axboe@kernel.dk, linux-block@vger.kernel.org,
        linux-kernel@vger.kernel.org, syzkaller-bugs@googlegroups.com,
        "James E.J. Bottomley" <jejb@linux.ibm.com>,
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        linux-scsi@vger.kernel.org,
        syzbot+f08c77040fa163a75a46@syzkaller.appspotmail.com
Subject: Re: [PATCH] scsi: sd: call device_del() if device_add_disk() fails
Message-ID: <20220330043025.GD3293@kadam>
References: <20220329154948.10350-1-fmdefrancesco@gmail.com>
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On Tue, Mar 29, 2022 at 05:49:48PM +0200, Fabio M. De Francesco wrote:
> In sd_probe(), if device_add_disk() fails it simply calls put_device()
> and jumps to the "out" label but the device is never deleted from system.
> This leads to a memory leak as reported by Syzbot.[1]
> 
> Fix this bug by calling device_del() soon before put_device() when 
> device_add_disk() fails.
> 
> [1] [syzbot] memory leak in blk_mq_init_tags
> https://lore.kernel.org/lkml/000000000000c341cc05db38c1b0@google.com/
> 
> Reported-by: syzbot+f08c77040fa163a75a46@syzkaller.appspotmail.com
> Suggested-by: Dan Carpenter <dan.carpenter@oracle.com>
> Fixes: 2a7a891f4c40 ("scsi: sd: Add error handling support for add_disk()")
> Signed-off-by: Fabio M. De Francesco <fmdefrancesco@gmail.com>

Thanks!

regards,
dan carpenter