From 9561f9671dbfb77ec7d319cd19c88e4be506004b Mon Sep 17 00:00:00 2001 From: Louis Scalbert Date: Tue, 28 Nov 2023 14:54:46 +0100 Subject: [PATCH] bgpd: fix bgp_best_selection heap-use-after-free Fix bgp_best_selection heap-use-after-free > ==2521540==ERROR: AddressSanitizer: heap-use-after-free on address 0x60d000032810 at pc 0x000000716f45 bp 0x7ffedc6229d0 sp 0x7ffedc6229c8 > READ of size 8 at 0x60d000032810 thread T0 > #0 0x716f44 in bgp_best_selection /home/lscalber/git/frr/bgpd/bgp_route.c:2834:5 > #1 0x71a05e in bgp_process_main_one /home/lscalber/git/frr/bgpd/bgp_route.c:3344:2 > #2 0x71c265 in bgp_process_wq /home/lscalber/git/frr/bgpd/bgp_route.c:3622:3 > #3 0x7fe630a6669c in work_queue_run /home/lscalber/git/frr/lib/workqueue.c:282:10 > #4 0x7fe630a294e2 in event_call /home/lscalber/git/frr/lib/event.c:1974:2 > #5 0x7fe630898f3f in frr_run /home/lscalber/git/frr/lib/libfrr.c:1214:3 > #6 0x4f4ace in main /home/lscalber/git/frr/bgpd/bgp_main.c:510:2 > #7 0x7fe63018bd09 in __libc_start_main csu/../csu/libc-start.c:308:16 > #8 0x449629 in _start (/usr/lib/frr/bgpd+0x449629) > > 0x60d000032810 is located 48 bytes inside of 144-byte region [0x60d0000327e0,0x60d000032870) > freed by thread T0 here: > #0 0x4c341d in free (/usr/lib/frr/bgpd+0x4c341d) > #1 0x7fe6308d7420 in qfree /home/lscalber/git/frr/lib/memory.c:130:2 > #2 0x702632 in bgp_path_info_free_with_caller /home/lscalber/git/frr/bgpd/bgp_route.c:300:2 > #3 0x702023 in bgp_path_info_unlock /home/lscalber/git/frr/bgpd/bgp_route.c:315:3 > #4 0x703bc6 in bgp_path_info_reap /home/lscalber/git/frr/bgpd/bgp_route.c:461:2 > #5 0x716e5d in bgp_best_selection /home/lscalber/git/frr/bgpd/bgp_route.c:2829:12 > #6 0x71a05e in bgp_process_main_one /home/lscalber/git/frr/bgpd/bgp_route.c:3344:2 > #7 0x71c265 in bgp_process_wq /home/lscalber/git/frr/bgpd/bgp_route.c:3622:3 > #8 0x7fe630a6669c in work_queue_run /home/lscalber/git/frr/lib/workqueue.c:282:10 > #9 0x7fe630a294e2 in event_call /home/lscalber/git/frr/lib/event.c:1974:2 > #10 0x7fe630898f3f in frr_run /home/lscalber/git/frr/lib/libfrr.c:1214:3 > #11 0x4f4ace in main /home/lscalber/git/frr/bgpd/bgp_main.c:510:2 > #12 0x7fe63018bd09 in __libc_start_main csu/../csu/libc-start.c:308:16 > > previously allocated by thread T0 here: > #0 0x4c3812 in calloc (/usr/lib/frr/bgpd+0x4c3812) > #1 0x7fe6308d7178 in qcalloc /home/lscalber/git/frr/lib/memory.c:105:27 > #2 0x71f5b4 in info_make /home/lscalber/git/frr/bgpd/bgp_route.c:3985:8 > #3 0x725293 in bgp_update /home/lscalber/git/frr/bgpd/bgp_route.c:4881:8 > #4 0x73083d in bgp_nlri_parse_ip /home/lscalber/git/frr/bgpd/bgp_route.c:6230:4 > #5 0x6ba980 in bgp_nlri_parse /home/lscalber/git/frr/bgpd/bgp_packet.c:341:10 > #6 0x6cca2a in bgp_update_receive /home/lscalber/git/frr/bgpd/bgp_packet.c:2412:15 > #7 0x6c6788 in bgp_process_packet /home/lscalber/git/frr/bgpd/bgp_packet.c:3887:11 > #8 0x7fe630a294e2 in event_call /home/lscalber/git/frr/lib/event.c:1974:2 > #9 0x7fe630898f3f in frr_run /home/lscalber/git/frr/lib/libfrr.c:1214:3 > #10 0x4f4ace in main /home/lscalber/git/frr/bgpd/bgp_main.c:510:2 > #11 0x7fe63018bd09 in __libc_start_main csu/../csu/libc-start.c:308:16 Fixes: ddb5b4880b ("bgpd: vpn-vrf route leaking") Signed-off-by: Louis Scalbert --- bgpd/bgp_route.c | 12 ++++++------ 1 file changed, 6 insertions(+), 6 deletions(-) diff --git a/bgpd/bgp_route.c b/bgpd/bgp_route.c index b4c97eb2eaf5..fb9370a1eb65 100644 --- a/bgpd/bgp_route.c +++ b/bgpd/bgp_route.c @@ -2824,18 +2824,18 @@ void bgp_best_selection(struct bgp *bgp, struct bgp_dest *dest, /* reap REMOVED routes, if needs be * selected route must stay for a while longer though */ - if (CHECK_FLAG(pi->flags, BGP_PATH_REMOVED) && - (pi != old_select)) { - dest = bgp_path_info_reap(dest, pi); - assert(dest); - } - if (debug) zlog_debug( "%s: %pBD(%s) pi from %s in holddown", __func__, dest, bgp->name_pretty, pi->peer->host); + if (CHECK_FLAG(pi->flags, BGP_PATH_REMOVED) && + (pi != old_select)) { + dest = bgp_path_info_reap(dest, pi); + assert(dest); + } + continue; }