Re: [PATCH] lpfc: Fix possible use-after-free and double free in lpfc_mbx_cmpl_rdp_page_a2()

[Johannes Thumshirn <jthumshirn@suse.de>]

Sebastian Herbszt <herbszt@gmx.de> writes:

> Johannes Thumshirn wrote:
>> If the bf_get() call in lpfc_mbx_cmpl_rdp_page_a2() does succeeds, execution
>> continues normally and mp gets kfree()d.
>> 
>> If the subsequent call to lpfc_sli_issue_mbox() fails execution jumps to the
>> error label where lpfc_mbuf_free() is called with mp->virt and mp->phys as
>> function arguments. This is the use after free. Following the use after free mp
>> gets kfree()d again which is a double free.
>
> A similar patch was posted by Colin Ian King on 2015-07-31 [1].
>
> [1] http://marc.info/?l=linux-scsi&m=143835937206204&w=2

OK,

Is it already in James' tree (haven't checked)? The problematic code was
merged for 4.2-rc1 so if the fix (Collin's or mine I don't care) could go
in while we're still in the rc phase, we could avoid all that stable
circus.

Thanks for digging this out.

Byte,
        Johannes