Re: [PATCH] net: xfrm: fix a race condition during allocing spi

On Thu, Oct 22, 2020 at 01:53:15PM +0800, zhuoliang.zhang wrote:

there are 2 related hash lists : net->xfrm.state_bydst and
net->xfrm.state_byspi:

1. a new state x is alloced in xfrm_state_alloc() and added into the
bydst hlist in  __find_acq_core() on the LHS;
2. on the RHS, state_hash_work thread travels the old bydst and tranfers
every xfrm_state (include x) to the new bydst hlist and new byspi hlist;
3. user thread on the LHS gets the lock and adds x to the new byspi
hlist again.

Good catch.  Please add a Fixes header.  I think this was introduced
with the dynamic resizing in f034b5d4efdfe0fb9e2a1ce1d95fa7914f24de49.

Thanks,
-- 
Email: Herbert Xu [off-list ref]
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