This is a note to let you know that I've just added the patch titled sched: cls_flow: fix panic on filter replace to the 4.1-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: sched-cls_flow-fix-panic-on-filter-replace.patch and it can be found in the queue-4.1 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From foo@baz Sat Sep 26 11:13:07 PDT 2015 From: Daniel Borkmann <daniel@xxxxxxxxxxxxx> Date: Fri, 17 Jul 2015 22:38:45 +0200 Subject: sched: cls_flow: fix panic on filter replace From: Daniel Borkmann <daniel@xxxxxxxxxxxxx> [ Upstream commit 32b2f4b196b37695fdb42b31afcbc15399d6ef91 ] The following test case causes a NULL pointer dereference in cls_flow: tc filter add dev foo parent 1: handle 0x1 flow hash keys dst action ok tc filter replace dev foo parent 1: pref 49152 handle 0x1 \ flow hash keys mark action drop To be more precise, actually two different panics are fixed, the first occurs because tcf_exts_init() is not called on the newly allocated filter when we do a replace. And the second panic uncovered after that happens since the arguments of list_replace_rcu() are swapped, the old element needs to be the first argument and the new element the second. Fixes: 70da9f0bf999 ("net: sched: cls_flow use RCU") Signed-off-by: Daniel Borkmann <daniel@xxxxxxxxxxxxx> Acked-by: John Fastabend <john.r.fastabend@xxxxxxxxx> Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- net/sched/cls_flow.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) --- a/net/sched/cls_flow.c +++ b/net/sched/cls_flow.c @@ -419,6 +419,8 @@ static int flow_change(struct net *net, if (!fnew) goto err2; + tcf_exts_init(&fnew->exts, TCA_FLOW_ACT, TCA_FLOW_POLICE); + fold = (struct flow_filter *)*arg; if (fold) { err = -EINVAL; @@ -480,7 +482,6 @@ static int flow_change(struct net *net, fnew->mask = ~0U; fnew->tp = tp; get_random_bytes(&fnew->hashrnd, 4); - tcf_exts_init(&fnew->exts, TCA_FLOW_ACT, TCA_FLOW_POLICE); } fnew->perturb_timer.function = flow_perturbation; @@ -520,7 +521,7 @@ static int flow_change(struct net *net, if (*arg == 0) list_add_tail_rcu(&fnew->list, &head->filters); else - list_replace_rcu(&fnew->list, &fold->list); + list_replace_rcu(&fold->list, &fnew->list); *arg = (unsigned long)fnew; Patches currently in stable-queue which might be from daniel@xxxxxxxxxxxxx are queue-4.1/sched-cls_bpf-fix-panic-on-filter-replace.patch queue-4.1/net-sched-fix-refcount-imbalance-in-actions.patch queue-4.1/sched-cls_flow-fix-panic-on-filter-replace.patch queue-4.1/act_bpf-fix-memory-leaks-when-replacing-bpf-programs.patch queue-4.1/packet-tpacket_snd-fix-signed-unsigned-comparison.patch queue-4.1/rtnetlink-verify-ifla_vf_info-attributes-before-passing-them-to-driver.patch queue-4.1/netlink-make-sure-ebusy-won-t-escape-from-netlink_insert.patch -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html