Re: [PATCH v2 net 5/5] ipv6: mcast: use jiffies_delta_to_clock_t() in igmp6_mc_seq_show()
From: Ido Schimmel <idosch@nvidia.com>
Date: 2026-08-30 15:45:40
On Fri, Aug 28, 2026 at 08:45:31AM +0000, Eric Dumazet wrote:
If a multicast group timer has expired but the delayed work has
not yet run to clear MAF_TIMER_RUNNING, expires - jiffies produces
a negative value.
Because unsigned arithmetic was used with jiffies_to_clock_t(),
expires - jiffies underflows to a huge value and reports invalid
timer durations in /proc/net/igmp6.
Use jiffies_delta_to_clock_t() with a signed long delta to properly
cap expired deltas to 0, matching IPv4 igmp_mc_seq_show() and commit
a399a8053164 ("time: jiffies_delta_to_clock_t() helper to the rescue").
Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Signed-off-by: Eric Dumazet <edumazet@google.com>Reviewed-by: Ido Schimmel <idosch@nvidia.com>