From 4d3c5c319b197357eb6ba8346a7c82fa287bebc3 Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Wed, 11 Aug 2021 12:57:15 -0700 Subject: [PATCH] net: igmp: increase size of mr_ifc_count [ Upstream commit b69dd5b3780a7298bd893816a09da751bc0636f7 ] Some arches support cmpxchg() on 4-byte and 8-byte only. Increase mr_ifc_count width to 32bit to fix this problem. Fixes: 4a2b285e7e10 ("net: igmp: fix data-race in igmp_ifc_timer_expire()") Signed-off-by: Eric Dumazet Reported-by: Guenter Roeck Link: https://lore.kernel.org/r/20210811195715.3684218-1-eric.dumazet@gmail.com Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin --- include/linux/inetdevice.h | 2 +- net/ipv4/igmp.c | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-) diff --git a/include/linux/inetdevice.h b/include/linux/inetdevice.h index 3515ca64e638..b68fca08be27 100644 --- a/include/linux/inetdevice.h +++ b/include/linux/inetdevice.h @@ -41,7 +41,7 @@ struct in_device { unsigned long mr_qri; /* Query Response Interval */ unsigned char mr_qrv; /* Query Robustness Variable */ unsigned char mr_gq_running; - unsigned char mr_ifc_count; + u32 mr_ifc_count; struct timer_list mr_gq_timer; /* general query timer */ struct timer_list mr_ifc_timer; /* interface change timer */ diff --git a/net/ipv4/igmp.c b/net/ipv4/igmp.c index cfa31c34b5bb..d2b1ae83f258 100644 --- a/net/ipv4/igmp.c +++ b/net/ipv4/igmp.c @@ -805,7 +805,7 @@ static void igmp_gq_timer_expire(struct timer_list *t) static void igmp_ifc_timer_expire(struct timer_list *t) { struct in_device *in_dev = from_timer(in_dev, t, mr_ifc_timer); - u8 mr_ifc_count; + u32 mr_ifc_count; igmpv3_send_cr(in_dev); restart: