linux-kernel - Re: [PATCH v6] i2c: virtio: add a virtio i2c frontend driver

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:   Wed, 10 Mar 2021 10:22:30 +0800
From:   Jie Deng <jie.deng@...el.com>
To:     Jason Wang <jasowang@...hat.com>, linux-i2c@...r.kernel.org,
        virtualization@...ts.linux-foundation.org,
        linux-kernel@...r.kernel.org
Cc:     mst@...hat.com, wsa@...nel.org, wsa+renesas@...g-engineering.com,
        andriy.shevchenko@...ux.intel.com, conghui.chen@...el.com,
        arnd@...db.de, kblaiech@...lanox.com,
        jarkko.nikula@...ux.intel.com, Sergey.Semin@...kalelectronics.ru,
        rppt@...nel.org, loic.poulain@...aro.org, tali.perry1@...il.com,
        u.kleine-koenig@...gutronix.de, bjorn.andersson@...aro.org,
        yu1.wang@...el.com, shuo.a.liu@...el.com, viresh.kumar@...aro.org,
        stefanha@...hat.com, pbonzini@...hat.com
Subject: Re: [PATCH v6] i2c: virtio: add a virtio i2c frontend driver


On 2021/3/4 17:15, Jason Wang wrote:
>
>
>> +        }
>> +
>> +        if (msgs[i].flags & I2C_M_RD)
>> +            memcpy(msgs[i].buf, req->buf, msgs[i].len);
>
>
> Sorry if I had asked this before but any rason not to use msg[i].buf 
> directly?
>
>
The msg[i].buf is passed by the I2C core. I just noticed that these bufs 
are not
always allocated by kmalloc. They may come from the stack, which may cause
the check "sg_init_one -> sg_set_buf -> virt_addr_valid"  to fail. 
Therefore the
msg[i].buf is not suitable for direct use here.

Regards.