linux-kernel - Re: [PATCH 1/2] tpm: Fix error handling in async work

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: Windows password security audit tool. GUI, reports in PDF.

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

Date:   Tue, 28 Dec 2021 16:08:42 -0800
From:   Tadeusz Struk <tstruk@...il.com>
To:     Jarkko Sakkinen <jarkko@...nel.org>
Cc:     Jason Gunthorpe <jgg@...pe.ca>, linux-integrity@...r.kernel.org,
        stable@...r.kernel.org, linux-kernel@...r.kernel.org
Subject: Re: [PATCH 1/2] tpm: Fix error handling in async work

On 12/28/21 15:47, Jarkko Sakkinen wrote:
>> When an invalid (non existing) handle is used in a tpm command,
>> that uses the resource manager interface (/dev/tpmrm0) the resource
>> manager tries to load it from its internal cache, but fails and
>> returns an -EINVAL error to the caller. The existing async handler
>> doesn't handle these error cases currently and the condition in the
>> poll handler never returns mask with EPOLLIN set causing the userspace
>> code to get stack. Make sure that error conditions also contribute
>> to the poll mask so that a correct error code could passed back
>> to the caller.
> Can you instead describe a failure scenario? This is very cryptic.

The problem is that the poll call blocks and the application gets stuck
until the tpm_timeout_work() wakes it up after 120 sec (jiffies + (120 * HZ)).
I will update the description, fix all the typos, and resend it.

Thanks,
Tadeusz