syzbot


KCSAN: data-race in dst_cache_set_ip6 / fib6_clean_node (5)

Status: auto-closed as invalid on 2022/01/10 22:59
Reported-by: syzbot+@syzkaller.appspotmail.com
First crash: 379d, last: 354d
similar bugs (4):
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in dst_cache_set_ip6 / fib6_clean_node 3 842d 880d 0/24 auto-closed as invalid on 2020/09/10 11:48
upstream KCSAN: data-race in dst_cache_set_ip6 / fib6_clean_node (3) 5 650d 679d 0/24 auto-closed as invalid on 2021/03/21 16:17
upstream KCSAN: data-race in dst_cache_set_ip6 / fib6_clean_node (4) 4 591d 606d 0/24 auto-closed as invalid on 2021/05/19 03:13
upstream KCSAN: data-race in dst_cache_set_ip6 / fib6_clean_node (2) 6 728d 715d 0/24 auto-closed as invalid on 2021/01/02 02:50

Sample crash report:
==================================================================
BUG: KCSAN: data-race in dst_cache_set_ip6 / fib6_clean_node

write to 0xffff8881283cc02c of 4 bytes by task 7 on cpu 0:
 fib6_clean_node+0xc2/0x260 net/ipv6/ip6_fib.c:2177
 fib6_walk_continue+0x38e/0x430 net/ipv6/ip6_fib.c:2111
 fib6_walk net/ipv6/ip6_fib.c:2159 [inline]
 fib6_clean_tree net/ipv6/ip6_fib.c:2239 [inline]
 __fib6_clean_all+0x1a9/0x2e0 net/ipv6/ip6_fib.c:2255
 fib6_flush_trees+0x6c/0x80 net/ipv6/ip6_fib.c:2280
 rt_genid_bump_ipv6 include/net/net_namespace.h:454 [inline]
 addrconf_dad_completed+0x57f/0x870 net/ipv6/addrconf.c:4230
 addrconf_dad_work+0x908/0x1170
 process_one_work+0x3fc/0x980 kernel/workqueue.c:2298
 worker_thread+0x616/0xa70 kernel/workqueue.c:2445
 kthread+0x2c7/0x2e0 kernel/kthread.c:327
 ret_from_fork+0x1f/0x30

read to 0xffff8881283cc02c of 4 bytes by task 1933 on cpu 1:
 fib6_get_cookie_safe include/net/ip6_fib.h:284 [inline]
 rt6_get_cookie include/net/ip6_fib.h:305 [inline]
 dst_cache_set_ip6+0xd3/0x1e0 net/core/dst_cache.c:115
 send6+0x270/0x3b0 drivers/net/wireguard/socket.c:148
 wg_socket_send_skb_to_peer+0xbb/0x130 drivers/net/wireguard/socket.c:177
 wg_packet_create_data_done drivers/net/wireguard/send.c:251 [inline]
 wg_packet_tx_worker+0x142/0x360 drivers/net/wireguard/send.c:276
 process_one_work+0x3fc/0x980 kernel/workqueue.c:2298
 worker_thread+0x616/0xa70 kernel/workqueue.c:2445
 kthread+0x2c7/0x2e0 kernel/kthread.c:327
 ret_from_fork+0x1f/0x30

value changed: 0x000001d2 -> 0x000001d4

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 1933 Comm: kworker/1:8 Not tainted 5.16.0-rc4-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: wg-crypt-wg0 wg_packet_tx_worker
==================================================================

Crashes (6):
Manager Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Title
ci2-upstream-kcsan-gce 2021/12/06 22:53 upstream f80ef9e49fdf 0230ba3e .config log report info KCSAN: data-race in dst_cache_set_ip6 / fib6_clean_node
ci2-upstream-kcsan-gce 2021/12/04 15:31 upstream 12119cfa1052 a617004c .config log report info KCSAN: data-race in dst_cache_set_ip6 / fib6_clean_node
ci2-upstream-kcsan-gce 2021/11/21 19:15 upstream 923dcc5eb0c1 4eb20a4e .config log report info KCSAN: data-race in dst_cache_set_ip6 / fib6_clean_node
ci2-upstream-kcsan-gce 2021/11/15 20:26 upstream 8ab774587903 75b04091 .config log report info KCSAN: data-race in dst_cache_set_ip6 / fib6_clean_node
ci2-upstream-kcsan-gce 2021/11/12 14:52 upstream 5833291ab6de 75b04091 .config log report info KCSAN: data-race in dst_cache_set_ip6 / fib6_clean_node
ci2-upstream-kcsan-gce 2021/11/12 01:05 upstream ca2ef2d9f2aa 75b04091 .config log report info KCSAN: data-race in dst_cache_set_ip6 / fib6_clean_node
* Struck through repros no longer work on HEAD.