Messages in this thread | | | Date | Wed, 28 Sep 2022 13:49:19 +0300 | From | Leon Romanovsky <> | Subject | Re: [syzbot] KASAN: use-after-free Read in rdma_close |
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On Wed, Sep 28, 2022 at 07:43:38PM +0900, asmadeus@codewreck.org wrote: > Leon Romanovsky wrote on Wed, Sep 28, 2022 at 01:07:23PM +0300: > > The bug is in commit 3ff51294a055 ("9p: p9_client_create: use p9_client_destroy on failure"). > > Thanks for looking > > > It is wrong to call to p9_client_destroy() if clnt->trans_mod->create fails. > > hmm that's a bit broad :) > > But I agree I did get that wrong: trans_mod->close() wasn't called if > create failed. > We do want the idr_for_each_entry() that is in p9_client_destroy so > rather than revert the commit (fix a bug, create a new one..) I'd rather > split it out in an internal function that takes a 'bool close' or > something to not duplicate the rest. > (Bit of a nitpick, sure)
Please do proper unwind without extra variable.
Proper unwind means that you will call to symmetrical functions in destroy as you used in create: alloc -> free create -> close e.t.c
When you use some global function like you did, there is huge chance to see unwind bugs.
> > I'll send a patch and credit you in Reported-by unless you don't want > to. > > -- > Dominique
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