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From: lyl2019@mail.ustc.edu.cn
To: paulus@samba.org, davem@davemloft.net
Cc: linux-ppp@vger.kernel.org, netdev@vger.kernel.org,
	linux-kernel@vger.kernel.org
Subject: [BUG] net/ppp: A use after free in ppp_unregister_channe
Date: Thu, 11 Mar 2021 12:34:44 +0000	[thread overview]
Message-ID: <6057386d.ca12.1782148389e.Coremail.lyl2019@mail.ustc.edu.cn> (raw)

File: drivers/net/ppp/ppp_generic.c

In ppp_unregister_channel, pch could be freed in ppp_unbridge_channels()
but after that pch is still in use. Inside the function ppp_unbridge_channels,
if "pchbb = pch" is true and then pch will be freed.

I checked the commit history and found that this problem is introduced from
4cf476ced45d7 ("ppp: add PPPIOCBRIDGECHAN and PPPIOCUNBRIDGECHAN ioctls").

I have no idea about how to generate a suitable patch, sorry.

             reply	other threads:[~2021-03-11 12:34 UTC|newest]

Thread overview: 8+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-03-11 12:34 lyl2019 [this message]
2021-03-12 10:12 ` Tom Parkin
2021-03-12 14:47   ` lyl2019
2021-03-15  9:57     ` Tom Parkin
2021-03-15 12:18     ` Guillaume Nault
2021-03-15 16:58       ` Tom Parkin
2021-03-15 12:04   ` Guillaume Nault
2021-03-15 11:50 ` Guillaume Nault

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