net/sched: act_mirred: better wording on protection against excessive stack growth
authorDavide Caratti <dcaratti@redhat.com>
Fri, 20 Jan 2023 17:01:39 +0000 (18:01 +0100)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Thu, 30 Mar 2023 10:49:20 +0000 (12:49 +0200)
commite0c12b9bfffcb56817bb5bada2da9d4a600cd64d
treec225b60ca656e6d5978215b55a72c14506b319fa
parenta0e39cdddc155926fc3c0395636b7c80e55e66a1
net/sched: act_mirred: better wording on protection against excessive stack growth

[ Upstream commit 78dcdffe0418ac8f3f057f26fe71ccf4d8ed851f ]

with commit e2ca070f89ec ("net: sched: protect against stack overflow in
TC act_mirred"), act_mirred protected itself against excessive stack growth
using per_cpu counter of nested calls to tcf_mirred_act(), and capping it
to MIRRED_RECURSION_LIMIT. However, such protection does not detect
recursion/loops in case the packet is enqueued to the backlog (for example,
when the mirred target device has RPS or skb timestamping enabled). Change
the wording from "recursion" to "nesting" to make it more clear to readers.

CC: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: Davide Caratti <dcaratti@redhat.com>
Reviewed-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Acked-by: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Stable-dep-of: ca22da2fbd69 ("act_mirred: use the backlog for nested calls to mirred ingress")
Signed-off-by: Sasha Levin <sashal@kernel.org>
net/sched/act_mirred.c