diff options
| author | Pedro Tammela <pctammela@mojatatu.com> | 2023-07-10 23:16:34 -0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2023-08-11 11:45:19 +0200 |
| commit | fbbf4dfe5d6a0fcb7a9a0aa2371e083767b060d5 (patch) | |
| tree | 2a9560109a413abd052ec9a8ef47d3515b36eca5 /include | |
| parent | 1e45a6f973a5bb7348c59a890b83809f2c121824 (diff) | |
net/sched: make psched_mtu() RTNL-less safe
[ Upstream commit 150e33e62c1fa4af5aaab02776b6c3812711d478 ]
Eric Dumazet says[1]:
-------
Speaking of psched_mtu(), I see that net/sched/sch_pie.c is using it
without holding RTNL, so dev->mtu can be changed underneath.
KCSAN could issue a warning.
-------
Annotate dev->mtu with READ_ONCE() so KCSAN don't issue a warning.
[1] https://lore.kernel.org/all/CANn89iJoJO5VtaJ-2=_d2aOQhb0Xw8iBT_Cxqp2HyuS-zj6azw@mail.gmail.com/
v1 -> v2: Fix commit message
Fixes: d4b36210c2e6 ("net: pkt_sched: PIE AQM scheme")
Suggested-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Pedro Tammela <pctammela@mojatatu.com>
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Link: https://lore.kernel.org/r/20230711021634.561598-1-pctammela@mojatatu.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Diffstat (limited to 'include')
| -rw-r--r-- | include/net/pkt_sched.h | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/include/net/pkt_sched.h b/include/net/pkt_sched.h index e09ea6917c06..83a16f3bd6e6 100644 --- a/include/net/pkt_sched.h +++ b/include/net/pkt_sched.h @@ -131,7 +131,7 @@ extern const struct nla_policy rtm_tca_policy[TCA_MAX + 1]; */ static inline unsigned int psched_mtu(const struct net_device *dev) { - return dev->mtu + dev->hard_header_len; + return READ_ONCE(dev->mtu) + dev->hard_header_len; } static inline struct net *qdisc_net(struct Qdisc *q) |