diff options
| author | Pedro Tammela <[email protected]> | 2023-07-10 23:16:34 -0300 |
|---|---|---|
| committer | Jakub Kicinski <[email protected]> | 2023-07-12 15:59:33 -0700 |
| commit | 150e33e62c1fa4af5aaab02776b6c3812711d478 (patch) | |
| tree | d2b769621b1ba460aae88201845b2185154ce6b4 | |
| parent | 1e9cb763e9bacf0c932aa948f50dcfca6f519a26 (diff) | |
net/sched: make psched_mtu() RTNL-less safe
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 <[email protected]>
Signed-off-by: Pedro Tammela <[email protected]>
Reviewed-by: Simon Horman <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Jakub Kicinski <[email protected]>
| -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 e98aac9d5ad5..15960564e0c3 100644 --- a/include/net/pkt_sched.h +++ b/include/net/pkt_sched.h @@ -134,7 +134,7 @@ 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) |