ipv6: mcast: annotate data-races around mca_users

/proc/net/igmp6 walks IPv6 multicast memberships under RCU and prints
mca_users without holding idev->mc_lock, while multicast join and leave
paths update the field while holding idev->mc_lock. Annotate this
intentional lockless snapshot with READ_ONCE() and the matching writers
with WRITE_ONCE().

Signed-off-by: Yuyang Huang <sigefriedhyy@gmail.com>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Link: https://patch.msgid.link/20260524022456.20689-1-sigefriedhyy@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
This commit is contained in:
Yuyang Huang 2026-05-24 11:24:56 +09:00 • committed by Jakub Kicinski
commit 56ed77ff60