[openwrt/openwrt] mac80211: fix division by zero in expected throughput estimation

[LEDE Commits]

nbd pushed a commit to openwrt/openwrt.git, branch main:
https://git.openwrt.org/886c4f054e5e34bc3de23d65da76180eea358c4a

commit 886c4f054e5e34bc3de23d65da76180eea358c4a
Author: Felix Fietkau <nbd at nbd.name>
AuthorDate: Sat Aug 9 16:47:45 2025 +0200

    mac80211: fix division by zero in expected throughput estimation
    
    Fixes: https://github.com/openwrt/openwrt/issues/19729
    Fixes: f10732fb5632 ("mac80211: estimate expected throughput if not provided by driver/rc")
    Signed-off-by: Felix Fietkau <nbd at nbd.name>
---
 .../361-mac80211-estimate-expected-throughput-if-not-provide.patch  | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/package/kernel/mac80211/patches/subsys/361-mac80211-estimate-expected-throughput-if-not-provide.patch b/package/kernel/mac80211/patches/subsys/361-mac80211-estimate-expected-throughput-if-not-provide.patch
index 9bcaf86504..81cff9e7e8 100644
--- a/package/kernel/mac80211/patches/subsys/361-mac80211-estimate-expected-throughput-if-not-provide.patch
+++ b/package/kernel/mac80211/patches/subsys/361-mac80211-estimate-expected-throughput-if-not-provide.patch
@@ -12,7 +12,7 @@ Signed-off-by: Felix Fietkau <nbd at nbd.name>
 
 --- a/net/mac80211/sta_info.c
 +++ b/net/mac80211/sta_info.c
-@@ -2621,6 +2621,27 @@ static inline u64 sta_get_stats_bytes(st
+@@ -2621,6 +2621,29 @@ static inline u64 sta_get_stats_bytes(st
  	return value;
  }
  
@@ -33,6 +33,8 @@ Signed-off-by: Felix Fietkau <nbd at nbd.name>
 +
 +	duration = ieee80211_rate_expected_tx_airtime(hw, NULL, ri, band, true, 1024);
 +	duration += duration >> 4; /* add assumed packet error rate of ~6% */
++	if (!duration)
++		return 0;
 +
 +	return ((1024 * USEC_PER_SEC) / duration) * 8;
 +}
@@ -40,7 +42,7 @@ Signed-off-by: Felix Fietkau <nbd at nbd.name>
  void sta_set_sinfo(struct sta_info *sta, struct station_info *sinfo,
  		   bool tidstats)
  {
-@@ -2865,6 +2886,8 @@ void sta_set_sinfo(struct sta_info *sta,
+@@ -2865,6 +2888,8 @@ void sta_set_sinfo(struct sta_info *sta,
  		sinfo->sta_flags.set |= BIT(NL80211_STA_FLAG_TDLS_PEER);
  
  	thr = sta_get_expected_throughput(sta);