From: Wei Wang <[email protected]> Date: Thu, 4 Oct 2018 10:12:37 -0700
> From: Wei Wang <[email protected]> > > In rawv6_send_hdrinc(), in order to avoid an extra dst_hold(), we > directly assign the dst to skb and set passed in dst to NULL to avoid > double free. > However, in error case, we free skb and then do stats update with the > dst pointer passed in. This causes use-after-free on the dst. > Fix it by taking rcu read lock right before dst could get released to > make sure dst does not get freed until the stats update is done. > Note: we don't have this issue in ipv4 cause dst is not used for stats > update in v4. > > Syzkaller reported following crash: ... > Fixes: 1789a640f556 ("raw: avoid two atomics in xmit") > Signed-off-by: Wei Wang <[email protected]> > Signed-off-by: Eric Dumazet <[email protected]> Applied and queued up for -stable, thanks.
