linux-kernel - Re: [PATCH] ubi: fastmap: fix ubi->fm memory leak

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] [day] [month] [year] [list]

Message-ID: <20251107093843.1077536-1-pangliyuan1@huawei.com>
Date: Fri, 7 Nov 2025 17:38:43 +0800
From: Liyuan Pang <pangliyuan1@...wei.com>
To: <markus.elfring@....de>
CC: <alexandre.torgue@...s.st.com>, <chengzhihao1@...wei.com>,
	<linux-arm-kernel@...ts.infradead.org>, <linux-kernel@...r.kernel.org>,
	<linux-mtd@...ts.infradead.org>, <linux-stm32@...md-mailman.stormreply.com>,
	<mcoquelin.stm32@...il.com>, <miquel.raynal@...tlin.com>,
	<pangliyuan1@...wei.com>, <richard@....at>, <vigneshr@...com>,
	<wanqian10@...wei.com>, <young.liuyang@...wei.com>
Subject: Re: [PATCH] ubi: fastmap: fix ubi->fm memory leak

>>> …
>>>> +++ b/drivers/mtd/ubi/fastmap.c
>>>> @@ -1644,3 +1644,15 @@ int ubi_update_fastmap(struct ubi_device *ubi)
>>> …
>>>> +void ubi_free_fastmap(struct ubi_device *ubi)
>>>> +{
>>>> +	int i;
>>>> +
>>>> +	if (ubi->fm) {
>>> +		for (i = 0; i < ubi->fm->used_blocks; i++)
>>> +			kmem_cache_free(ubi_wl_entry_slab, ubi->fm->e[i]);
>>> …
>>> +	}
>>> +}
>>> …
>>>
>>> May the local variable “i” be defined in the loop header?
>> 
>> I think it's better to leave it as it is, most of the code in
>> ubi defines variables outside the loop header, and defining
>> "i" in the loop header may cause compilation error in some old
>> kernel versions that use C89.
>
>Would you support to reduce the scope for such a variable to
>the code block of the if branch?

Ok, I will send a v2 patch.

Regards,
Liyuan