linux-kernel - Re: [PATCH] HID: hidraw: fix a problem of memory leak in hidraw

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 for Android: free password hash cracker in your pocket

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

Date: Thu, 25 Jan 2024 15:30:14 +0800
From: Su Hui <suhui@...china.com>
To: Dan Carpenter <dan.carpenter@...aro.org>
Cc: jikos@...nel.org, benjamin.tissoires@...hat.com, mail@...thek.com,
 linux-input@...r.kernel.org, linux-kernel@...r.kernel.org,
 kernel-janitors@...r.kernel.org
Subject: Re: [PATCH] HID: hidraw: fix a problem of memory leak in
 hidraw_release()

On 2024/1/25 15:11, Dan Carpenter wrote:
> On Thu, Jan 25, 2024 at 02:32:26PM +0800, Su Hui wrote:
>> 'struct hidraw_list' is a circular queue whose head can be smaller than
>> tail. Using 'list->tail != list->head' to release all memory that should
>> be released.
>>
>> Fixes: a5623a203cff ("HID: hidraw: fix memory leak in hidraw_release()")
>> Signed-off-by: Su Hui <suhui@...china.com>
> This is very clever.  How did you find that?  Was it through static
> analysis or just review?  Perhaps using syzkaller?
Hi,

I just met this bug on a real machine and found this problem by 
reviewing the code.

>
> Reviewed-by: Dan Carpenter <dan.carpenter@...aro.org>
>
> I imagine we could write a checker heuristic to identify ->tail and
> ->head struct members and then complain if they were ever used in a <
> or > comparison.

I can't agree any more, great idea!

Su Hui