mirror/nginx
1
0
Fork 0
mirror of https://github.com/nginx/nginx.git synced 2025-07-22 20:38:26 +08:00
Code Issues Actions Packages Projects Releases Wiki Activity

QUIC: ngx_msec_t overflow protection.

Browse Source 
On some systems the value of ngx_current_msec is derived from monotonic
clock, for which the following is defined by POSIX:

   For this clock, the value returned by clock_gettime() represents
   the amount of time (in seconds and nanoseconds) since an unspecified
   point in the past.

As as result, overflow protection is needed when comparing two ngx_msec_t.
The change adds such protection to the ngx_quic_detect_lost() function.
This commit is contained in:
Roman Arutyunyan 2025-03-10 12:19:25 +04:00 committed by Roman Arutyunyan
parent 38236bf74f
commit 1e883a40db
1 changed files with 14 additions and 8 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

22
src/event/quic/ngx_event_quic_ack.c
View File

@ -449,9 +449,10 @@ ngx_quic_detect_lost(ngx_connection_t *c, ngx_quic_ack_stat_t *st)
now = ngx_current_msec;
thr = ngx_quic_lost_threshold(qc);
/* send time of lost packets across all send contexts */
oldest = NGX_TIMER_INFINITE;
newest = NGX_TIMER_INFINITE;
#if (NGX_SUPPRESS_WARN)
oldest = now;
newest = now;
#endif
nlost = 0;
@ -484,13 +485,17 @@ ngx_quic_detect_lost(ngx_connection_t *c, ngx_quic_ack_stat_t *st)
break;
}
if (start->send_time > qc->first_rtt) {
if ((ngx_msec_int_t) (start->send_time - qc->first_rtt) > 0) {
if (oldest == NGX_TIMER_INFINITE || start->send_time < oldest) {
if (nlost == 0
|| (ngx_msec_int_t) (start->send_time - oldest) < 0)
{
oldest = start->send_time;
}
if (newest == NGX_TIMER_INFINITE || start->send_time > newest) {
if (nlost == 0
|| (ngx_msec_int_t) (start->send_time - newest) > 0)
{
newest = start->send_time;
}
@ -511,8 +516,9 @@ ngx_quic_detect_lost(ngx_connection_t *c, ngx_quic_ack_stat_t *st)
* latest ACK frame.
*/
if (st && nlost >= 2 && (st->newest < oldest || st->oldest > newest)) {
if (st && nlost >= 2 && ((ngx_msec_int_t) (st->newest - oldest) < 0
|| (ngx_msec_int_t) (st->oldest - newest) > 0))
{
if (newest - oldest > ngx_quic_pcg_duration(c)) {
ngx_quic_persistent_congestion(c);
}