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From: David Howells <dhowells@redhat.com>
In-Reply-To: <202211100616.HvYb1VNT-lkp@intel.com>
References: <202211100616.HvYb1VNT-lkp@intel.com>
To: Dan Carpenter <error27@gmail.com>
Cc: dhowells@redhat.com, oe-kbuild@lists.linux.dev, lkp@intel.com,
    oe-kbuild-all@lists.linux.dev, Ammar Faizi <ammarfaizi2@gnuweeb.org>,
    GNU/Weeb Mailing List <gwml@vger.gnuweeb.org>
Subject: Re: [ammarfaizi2-block:dhowells/linux-fs/rxrpc-ringless-5 19/77] net/rxrpc/input.c:519 rxrpc_input_data() warn: passing freed memory 'skb'
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Dan Carpenter <error27@gmail.com> wrote:

> We can't use "skb" after skb_unshare().  It means we dropped our
> reference to the skb.  The other reference holder probably holds a
> reference so it will probably work, but it could also race and lead to
> a use after free.
> 
> This only affects tracing code and not regular runtime but it's still a
> bug.

Nothing in rxrpc_eaten_skb() actually dereferences the skbuff pointer.  The
tracepoint merely logs the address.

David