From 57aa1718d5953dd532137d43b696c68545c2e0b3 Mon Sep 17 00:00:00 2001 From: Stanislaw Gruszka Date: Fri, 24 Jul 2026 11:55:45 +0200 Subject: [PATCH] wifi: iwlegacy: replace BUG_ON() with WARN_ON() on num_stations check BUG_ON() for il->num_stations < 0 can happen in real word, see https://bugzilla.kernel.org/show_bug.cgi?id=221733 Replace BUG_ON() with WARN_ON() (and reset the counter to 0) to do not put whole system to inconsistent state on the condition. Also allocate debugfs buffer for all stations (32 or 25) to do not use num_stations since it might not be right. Signed-off-by: Stanislaw Gruszka Link: https://patch.msgid.link/20260724095545.33647-1-stf_xl@wp.pl [clarify commit message wrt. debugfs buffer] Signed-off-by: Johannes Berg --- drivers/net/wireless/intel/iwlegacy/common.c | 7 ++++--- drivers/net/wireless/intel/iwlegacy/debug.c | 2 +- 2 files changed, 5 insertions(+), 4 deletions(-) diff --git a/drivers/net/wireless/intel/iwlegacy/common.c b/drivers/net/wireless/intel/iwlegacy/common.c index 8d0ff339ad08..0bb807ff8edf 100644 --- a/drivers/net/wireless/intel/iwlegacy/common.c +++ b/drivers/net/wireless/intel/iwlegacy/common.c @@ -2179,8 +2179,8 @@ il_remove_station(struct il_priv *il, const u8 sta_id, const u8 * addr) il->stations[sta_id].used &= ~IL_STA_DRIVER_ACTIVE; il->num_stations--; - - BUG_ON(il->num_stations < 0); + if (WARN_ON(il->num_stations < 0)) + il->num_stations = 0; spin_unlock_irqrestore(&il->sta_lock, flags); @@ -2328,7 +2328,8 @@ il_dealloc_bcast_stations(struct il_priv *il) il->stations[i].used &= ~IL_STA_UCODE_ACTIVE; il->num_stations--; - BUG_ON(il->num_stations < 0); + if (WARN_ON(il->num_stations < 0)) + il->num_stations = 0; kfree(il->stations[i].lq); il->stations[i].lq = NULL; } diff --git a/drivers/net/wireless/intel/iwlegacy/debug.c b/drivers/net/wireless/intel/iwlegacy/debug.c index d998a3f1b056..8a9f79ff1c6e 100644 --- a/drivers/net/wireless/intel/iwlegacy/debug.c +++ b/drivers/net/wireless/intel/iwlegacy/debug.c @@ -396,7 +396,7 @@ il_dbgfs_stations_read(struct file *file, char __user *user_buf, size_t count, int i, j, pos = 0; ssize_t ret; /* Add 30 for initial string */ - const size_t bufsz = 30 + sizeof(char) * 500 * (il->num_stations); + const size_t bufsz = 30 + sizeof(char) * 500 * max_sta; buf = kmalloc(bufsz, GFP_KERNEL); if (!buf)