Linux Media Controller development
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From: syzbot <syzbot@syzkaller.appspotmail.com>
To: mokshpanicker.7@gmail.com
Cc: linux-media@vger.kernel.org, mchehab@kernel.org,
	mokshpanicker.7@gmail.com
Subject: Re: [PATCH v2] media: mxl111sf: fix null pointer dereference in mxl111sf_ctrl_msg
Date: Sun, 10 May 2026 09:29:19 -0700	[thread overview]
Message-ID: <6a00b25f.a00a0220.1c3806.0012.GAE@google.com> (raw)
In-Reply-To: <20260510162912.67381-1-mokshpanicker.7@gmail.com>

> When mxl111sf_ctrl_msg() is called during early probe, state->d
> may not yet be initialized, causing a null pointer dereference in
> dvb_usbv2_generic_write() when it accesses d->usb_mutex.
>
> Add a null check for d before proceeding with the USB transfer.
>
> Fixes: d90b336f3f65 ("[media] mxl111sf: Fix driver to use heap allocate buffers for USB messages")
> Reported-by: syzbot+f9f333782a8f54509322@syzkaller.appspotmail.com
> Closes: https://syzkaller.appspot.com/bug?extid=f9f333782a8f54509322
> Signed-off-by: Moksh Panicker <mokshpanicker.7@gmail.com>
> ---
>  drivers/media/usb/dvb-usb-v2/mxl111sf.c | 3 +++
>  1 file changed, 3 insertions(+)
>
> diff --git a/drivers/media/usb/dvb-usb-v2/mxl111sf.c b/drivers/media/usb/dvb-usb-v2/mxl111sf.c
> index 870ac3c8b085..9908675c355e 100644
> --- a/drivers/media/usb/dvb-usb-v2/mxl111sf.c
> +++ b/drivers/media/usb/dvb-usb-v2/mxl111sf.c
> @@ -56,6 +56,9 @@ int mxl111sf_ctrl_msg(struct mxl111sf_state *state,
>  	int wo = (rbuf == NULL || rlen == 0); /* write-only */
>  	int ret;
>  
> +	if (!d)
> +		return -ENODEV;
> +
>  	if (1 + wlen > MXL_MAX_XFER_SIZE) {
>  		pr_warn("%s: len=%d is too big!\n", __func__, wlen);
>  		return -EOPNOTSUPP;
> -- 
> 2.34.1
>

I see the command but can't find the corresponding bug.
The email is sent to  syzbot+HASH@syzkaller.appspotmail.com address
but the HASH does not correspond to any known bug.
Please double check the address.


  reply	other threads:[~2026-05-10 16:29 UTC|newest]

Thread overview: 5+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2026-05-10 16:24 [PATCH] media: mxl111sf: fix null pointer dereference in mxl111sf_ctrl_msg Moksh Panicker
2026-05-10 16:29 ` [PATCH v2] " Moksh Panicker
2026-05-10 16:29   ` syzbot [this message]
2026-05-10 17:24   ` [PATCH v3] " Moksh Panicker
2026-05-11 10:13     ` [PATCH v4] " Moksh Panicker

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