From 9613cd06a5a8d2dd89d55b2c13ac311b7a25f5c1 Mon Sep 17 00:00:00 2001 From: Christopher Faulet Date: Tue, 9 Jul 2024 18:51:43 +0200 Subject: [PATCH] BUG/MEDIUM: bwlim: Be sure to never set the analyze expiration date in past Every time a bandwidth limitation is evaluated on a channel, the analyze expiration date is renewed, mainly based on the internal bandwidth limitation filter expiration date. However, when the filter is called while there is no data to filter, we skip all limitation computations to jump at the end of the function. At this stage, the analyze expiration date is renewed before exiting. But here the internal expiration date may be expired and not reset. To sum up, it is possible to set the analyze expiration date of a channel in the past. It is unexpected and this could lead to a loop in process_stream. To fix the issue, we just now take care to reset the internal expiration date, if needed, before exiting. This patch should fix the issue #2634. It must be backported as far as 2.8. (cherry picked from commit 2cb5b7dca688e59146256833153ad700302004ba) Signed-off-by: Willy Tarreau --- src/flt_bwlim.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/src/flt_bwlim.c b/src/flt_bwlim.c index c5078c841..11eb2484a 100644 --- a/src/flt_bwlim.c +++ b/src/flt_bwlim.c @@ -85,10 +85,13 @@ static int bwlim_apply_limit(struct filter *filter, struct channel *chn, unsigne /* Don't forward anything if there is nothing to forward or the waiting * time is not expired */ - if (!len || (tick_isset(st->exp) && !tick_is_expired(st->exp, now_ms))) + if (tick_isset(st->exp) && !tick_is_expired(st->exp, now_ms)) goto end; st->exp = TICK_ETERNITY; + if (!len) + goto end; + ret = len; if (conf->flags & BWLIM_FL_SHARED) { void *ptr; @@ -177,6 +180,7 @@ static int bwlim_apply_limit(struct filter *filter, struct channel *chn, unsigne end: chn->analyse_exp = tick_first((tick_is_expired(chn->analyse_exp, now_ms) ? TICK_ETERNITY : chn->analyse_exp), st->exp); + BUG_ON(tick_is_expired(chn->analyse_exp, now_ms)); return ret; }