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To:     Xiaomeng Tong <xiam0nd.tong@gmail.com>
Cc:     oliver@neukum.org, aliakc@web.de, lenehan@twibble.org,
        jejb@linux.ibm.com, martin.petersen@oracle.com, dc395x@twibble.org,
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Subject: Re: [RESEND][PATCH] scsi: dc395x: fix a missing check on list iterator
From:   "Martin K. Petersen" <martin.petersen@oracle.com>
Organization: Oracle Corporation
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Date:   Tue, 26 Apr 2022 08:52:58 -0400
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Xiaomeng,

> The bug is here:
> 	p->target_id, p->target_lun);
>
> The list iterator 'p' will point to a bogus position containing HEAD
> if the list is empty or no element is found. This case must be checked
> before any use of the iterator, otherwise it will lead to a invalid
> memory access.
>
> To fix this bug, add an check. Use a new variable 'iter' as the list
> iterator, while use the origin variable 'p' as a dedicated pointer to
> point to the found element.

Applied to 5.19/scsi-staging, thanks!

-- 
Martin K. Petersen	Oracle Linux Engineering