Re: [PATCH v3] HID: memory leak in dualshock4_get_calibration_data

[Jiri Slaby <jirislaby@kernel.org>]

On 22. 11. 25, 18:37, Eslam Khafagy wrote:
> Function dualshock4_get_calibration_data allocates memory to pointer
> buf .However, the function may exit prematurely due to transfer_failure
> in this case it does not handle freeing memory.
> 
> This patch handles memory deallocation at exit.

Isn't this fixed already by:
commit 8513c154f8ad7097653dd9bf43d6155e5aad4ab3
Author: Abdun Nihaal <nihaal@cse.iitm.ac.in>
Date:   Mon Nov 10 22:45:50 2025 +0530

     HID: playstation: Fix memory leak in dualshock4_get_calibration_data()
?

Anyway, this is a typical use-case for __free(). Why not to use that?

> Reported-by: syzbot+4f5f81e1456a1f645bf8@syzkaller.appspotmail.com
> Closes: https://lore.kernel.org/all/691560c4.a70a0220.3124cb.0019.GAE@google.com/T/
> Tested-by: syzbot+4f5f81e1456a1f645bf8@syzkaller.appspotmail.com
> Fixes: 947992c7fa9e0 ("HID: playstation: DS4: Fix calibration workaround for clone devices")
> Cc: stable@vger.kernel.org
> Signed-off-by: Eslam Khafagy <eslam.medhat1993@gmail.com>
> ---
> v3:
> * Address issues reported by checkpatch and re-format commit message
> for better readability
> * kfree() is safe so no need to check for NULL pointer
> 
> v2: https://lore.kernel.org/all/20251116022723.29857-1-eslam.medhat1993@gmail.com/
> * Adding tag "Cc: stable@vger.kernel.org"
> 
> v1: https://lore.kernel.org/all/20251115022323.1395726-1-eslam.medhat1993@gmail.com/
>   
> 
>   drivers/hid/hid-playstation.c | 6 +++---
>   1 file changed, 3 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/hid/hid-playstation.c b/drivers/hid/hid-playstation.c
> index 128aa6abd10b..05a8522ace4f 100644
> --- a/drivers/hid/hid-playstation.c
> +++ b/drivers/hid/hid-playstation.c
> @@ -1994,9 +1994,6 @@ static int dualshock4_get_calibration_data(struct dualshock4 *ds4)
>   	acc_z_plus       = get_unaligned_le16(&buf[31]);
>   	acc_z_minus      = get_unaligned_le16(&buf[33]);
>   
> -	/* Done parsing the buffer, so let's free it. */
> -	kfree(buf);
> -
>   	/*
>   	 * Set gyroscope calibration and normalization parameters.
>   	 * Data values will be normalized to 1/DS4_GYRO_RES_PER_DEG_S degree/s.
> @@ -2043,6 +2040,9 @@ static int dualshock4_get_calibration_data(struct dualshock4 *ds4)
>   	ds4->accel_calib_data[2].sens_denom = range_2g;
>   
>   transfer_failed:
> +	/* First free buf if still allocated */
> +	kfree(buf);
> +
>   	/*
>   	 * Sanity check gyro calibration data. This is needed to prevent crashes
>   	 * during report handling of virtual, clone or broken devices not implementing

-- 
js
suse labs