From: Dan Carpenter Date: Tue, 23 Sep 2025 11:19:11 +0000 (+0300) Subject: octeontx2-pf: Fix potential use after free in otx2_tc_add_flow() X-Git-Tag: v6.17~19^2 X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=d9c70e93ec5988ab07ad2a92d9f9d12867f02c56;p=thirdparty%2Flinux.git octeontx2-pf: Fix potential use after free in otx2_tc_add_flow() This code calls kfree_rcu(new_node, rcu) and then dereferences "new_node" and then dereferences it on the next line. Two lines later, we take a mutex so I don't think this is an RCU safe region. Re-order it to do the dereferences before queuing up the free. Fixes: 68fbff68dbea ("octeontx2-pf: Add police action for TC flower") Signed-off-by: Dan Carpenter Reviewed-by: Vadim Fedorenko Link: https://patch.msgid.link/aNKCL1jKwK8GRJHh@stanley.mountain Signed-off-by: Paolo Abeni --- diff --git a/drivers/net/ethernet/marvell/octeontx2/nic/otx2_tc.c b/drivers/net/ethernet/marvell/octeontx2/nic/otx2_tc.c index 5f80b23c5335c..26a08d2cfbb1b 100644 --- a/drivers/net/ethernet/marvell/octeontx2/nic/otx2_tc.c +++ b/drivers/net/ethernet/marvell/octeontx2/nic/otx2_tc.c @@ -1326,7 +1326,6 @@ static int otx2_tc_add_flow(struct otx2_nic *nic, free_leaf: otx2_tc_del_from_flow_list(flow_cfg, new_node); - kfree_rcu(new_node, rcu); if (new_node->is_act_police) { mutex_lock(&nic->mbox.lock); @@ -1346,6 +1345,7 @@ free_leaf: mutex_unlock(&nic->mbox.lock); } + kfree_rcu(new_node, rcu); return rc; }