From 49dba1ded8dd5a6a12748631403240b2ab245c34 Mon Sep 17 00:00:00 2001 From: Issam Hamdi Date: Mon, 25 Nov 2024 17:29:20 +0100 Subject: [PATCH] wifi: mac80211: fix mbss changed flags corruption on 32 bit systems On 32-bit systems, the size of an unsigned long is 4 bytes, while a u64 is 8 bytes. Therefore, when using or_each_set_bit(bit, &bits, sizeof(changed) * BITS_PER_BYTE), the code is incorrectly searching for a bit in a 32-bit variable that is expected to be 64 bits in size, leading to incorrect bit finding. Solution: Ensure that the size of the bits variable is correctly adjusted for each architecture. Call Trace: ? show_regs+0x54/0x58 ? __warn+0x6b/0xd4 ? ieee80211_link_info_change_notify+0xcc/0xd4 [mac80211] ? report_bug+0x113/0x150 ? exc_overflow+0x30/0x30 ? handle_bug+0x27/0x44 ? exc_invalid_op+0x18/0x50 ? handle_exception+0xf6/0xf6 ? exc_overflow+0x30/0x30 ? ieee80211_link_info_change_notify+0xcc/0xd4 [mac80211] ? exc_overflow+0x30/0x30 ? ieee80211_link_info_change_notify+0xcc/0xd4 [mac80211] ? ieee80211_mesh_work+0xff/0x260 [mac80211] ? cfg80211_wiphy_work+0x72/0x98 [cfg80211] ? process_one_work+0xf1/0x1fc ? worker_thread+0x2c0/0x3b4 ? kthread+0xc7/0xf0 ? mod_delayed_work_on+0x4c/0x4c ? kthread_complete_and_exit+0x14/0x14 ? ret_from_fork+0x24/0x38 ? kthread_complete_and_exit+0x14/0x14 ? ret_from_fork_asm+0xf/0x14 ? entry_INT80_32+0xf0/0xf0 Signed-off-by: Issam Hamdi Link: https://patch.msgid.link/20241125162920.2711462-1-ih@simonwunderlich.de [restore no-op path for no changes] Signed-off-by: Johannes Berg --- net/mac80211/mesh.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/net/mac80211/mesh.c b/net/mac80211/mesh.c index cb5f16366b9c..974081324aa4 100644 --- a/net/mac80211/mesh.c +++ b/net/mac80211/mesh.c @@ -1157,14 +1157,14 @@ void ieee80211_mbss_info_change_notify(struct ieee80211_sub_if_data *sdata, u64 changed) { struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh; - unsigned long bits = changed; + unsigned long bits[] = { BITMAP_FROM_U64(changed) }; u32 bit; - if (!bits) + if (!changed) return; /* if we race with running work, worst case this work becomes a noop */ - for_each_set_bit(bit, &bits, sizeof(changed) * BITS_PER_BYTE) + for_each_set_bit(bit, bits, sizeof(changed) * BITS_PER_BYTE) set_bit(bit, ifmsh->mbss_changed); set_bit(MESH_WORK_MBSS_CHANGED, &ifmsh->wrkq_flags); wiphy_work_queue(sdata->local->hw.wiphy, &sdata->work);