bisecting fixing commit since 9f84340f012ee60c12aacc03662bcdd67419a31a building syzkaller on 4846d5c1dcbf362c2e9949b24feca9670ca9b4b9 testing commit 9f84340f012ee60c12aacc03662bcdd67419a31a compiler: gcc version 8.4.1 20210217 (GCC) kernel signature: 2ed3eaf69d442b650dce9bf1f70684ad89a22db1df3d601ed4e0b5578ddce558 all runs: crashed: WARNING: suspicious RCU usage in vxlan_xmit testing current HEAD 6ca2f514c57864e3085a65c5e9d2adca4144bc4c testing commit 6ca2f514c57864e3085a65c5e9d2adca4144bc4c compiler: gcc version 8.4.1 20210217 (GCC) kernel signature: 658b32febb80181128c65363a96239b5035779359007db71e58868e46b7f0721 all runs: OK # git bisect start 6ca2f514c57864e3085a65c5e9d2adca4144bc4c 9f84340f012ee60c12aacc03662bcdd67419a31a Bisecting: 312 revisions left to test after this (roughly 8 steps) [dd16e38e1531258d332b0fc7c247367f60c6c381] sctp: add size validation when walking chunks testing commit dd16e38e1531258d332b0fc7c247367f60c6c381 compiler: gcc version 8.4.1 20210217 (GCC) kernel signature: 3676b640c0aebd6a32d443ed655ecf7855c988312eefacadb662c7022a406f4b all runs: OK # git bisect bad dd16e38e1531258d332b0fc7c247367f60c6c381 Bisecting: 155 revisions left to test after this (roughly 7 steps) [4de95ea6e064f0e519e4899d14705406e105f1bd] net: pch_gbe: Propagate error from devm_gpio_request_one() testing commit 4de95ea6e064f0e519e4899d14705406e105f1bd compiler: gcc version 8.4.1 20210217 (GCC) kernel signature: d06ae87b9df73f24e0815863bcdeadca1773f0f62f48ad0fa7c6bcff9e1e6498 all runs: crashed: WARNING: suspicious RCU usage in vxlan_xmit # git bisect good 4de95ea6e064f0e519e4899d14705406e105f1bd Bisecting: 77 revisions left to test after this (roughly 6 steps) [3ce7cd150ef7821508c142f4755fe4c327f79df2] iio: adc: hx711: Fix buffer alignment in iio_push_to_buffers_with_timestamp() testing commit 3ce7cd150ef7821508c142f4755fe4c327f79df2 compiler: gcc version 8.4.1 20210217 (GCC) kernel signature: 299c4da4d014635a4b345511f04147f6ab013c6704eaf373b508dc1d0a8bb3d3 all runs: OK # git bisect bad 3ce7cd150ef7821508c142f4755fe4c327f79df2 Bisecting: 38 revisions left to test after this (roughly 5 steps) [4a808634e5a6eb74eb7423cb999c1892a5c7b547] Bluetooth: Fix handling of HCI_LE_Advertising_Set_Terminated event testing commit 4a808634e5a6eb74eb7423cb999c1892a5c7b547 compiler: gcc version 8.4.1 20210217 (GCC) kernel signature: fb75f43e509cea705cb55a7b0996364d9609d294034b8a906ae56709a6ad667b all runs: OK # git bisect bad 4a808634e5a6eb74eb7423cb999c1892a5c7b547 Bisecting: 19 revisions left to test after this (roughly 4 steps) [1853dabfd1516682192cd40595feaa86e69a3bba] RDMA/rxe: Fix qp reference counting for atomic ops testing commit 1853dabfd1516682192cd40595feaa86e69a3bba compiler: gcc version 8.4.1 20210217 (GCC) kernel signature: a92bcabdb58b8d74cd97a494b6d569d6568ffe92b00a57fcbe28ea8a0fb94ea2 all runs: crashed: WARNING: suspicious RCU usage in vxlan_xmit # git bisect good 1853dabfd1516682192cd40595feaa86e69a3bba Bisecting: 9 revisions left to test after this (roughly 3 steps) [2f001552df5e3e183ed80e1fc60fcbd7698b0904] mac80211: remove iwlwifi specific workaround NDPs of null_response testing commit 2f001552df5e3e183ed80e1fc60fcbd7698b0904 compiler: gcc version 8.4.1 20210217 (GCC) kernel signature: dc4f696e9b89c7d1b39817ba10004d9d308f3147b1cb3ea208d0d53b362fc9d8 all runs: OK # git bisect bad 2f001552df5e3e183ed80e1fc60fcbd7698b0904 Bisecting: 4 revisions left to test after this (roughly 2 steps) [98fd088c325429327fc5ddb0b12c6a203ebf7f30] pkt_sched: sch_qfq: fix qfq_change_class() error path testing commit 98fd088c325429327fc5ddb0b12c6a203ebf7f30 compiler: gcc version 8.4.1 20210217 (GCC) kernel signature: 0973e9077f929475df76d949a408dc53ecdafceb7d892cad2d3e0633d6592fc6 all runs: crashed: WARNING: suspicious RCU usage in vxlan_xmit # git bisect good 98fd088c325429327fc5ddb0b12c6a203ebf7f30 Bisecting: 2 revisions left to test after this (roughly 1 step) [0cb6b100b869164dcd4b48e8c236e0a9f1c8c0ad] net/ipv4: swap flow ports when validating source testing commit 0cb6b100b869164dcd4b48e8c236e0a9f1c8c0ad compiler: gcc version 8.4.1 20210217 (GCC) kernel signature: e25d702ad4160f42bd5d3778cce43b7d8cce1be5fba98e5442c548e4c56ef6c7 all runs: OK # git bisect bad 0cb6b100b869164dcd4b48e8c236e0a9f1c8c0ad Bisecting: 0 revisions left to test after this (roughly 0 steps) [f80201ff7937fddb039716ba5948775b485d7646] vxlan: add missing rcu_read_lock() in neigh_reduce() testing commit f80201ff7937fddb039716ba5948775b485d7646 compiler: gcc version 8.4.1 20210217 (GCC) kernel signature: e57a33f67a55ebc28f80f8650c1204fa16b6089fb502204f35d0ba49988f5a0e all runs: OK # git bisect bad f80201ff7937fddb039716ba5948775b485d7646 f80201ff7937fddb039716ba5948775b485d7646 is the first bad commit commit f80201ff7937fddb039716ba5948775b485d7646 Author: Eric Dumazet Date: Mon Jun 21 07:44:17 2021 -0700 vxlan: add missing rcu_read_lock() in neigh_reduce() [ Upstream commit 85e8b032d6ebb0f698a34dd22c2f13443d905888 ] syzbot complained in neigh_reduce(), because rcu_read_lock_bh() is treated differently than rcu_read_lock() WARNING: suspicious RCU usage 5.13.0-rc6-syzkaller #0 Not tainted ----------------------------- include/net/addrconf.h:313 suspicious rcu_dereference_check() usage! other info that might help us debug this: rcu_scheduler_active = 2, debug_locks = 1 3 locks held by kworker/0:0/5: #0: ffff888011064d38 ((wq_completion)events){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff888011064d38 ((wq_completion)events){+.+.}-{0:0}, at: atomic64_set include/asm-generic/atomic-instrumented.h:856 [inline] #0: ffff888011064d38 ((wq_completion)events){+.+.}-{0:0}, at: atomic_long_set include/asm-generic/atomic-long.h:41 [inline] #0: ffff888011064d38 ((wq_completion)events){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:617 [inline] #0: ffff888011064d38 ((wq_completion)events){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:644 [inline] #0: ffff888011064d38 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x871/0x1600 kernel/workqueue.c:2247 #1: ffffc90000ca7da8 ((work_completion)(&port->wq)){+.+.}-{0:0}, at: process_one_work+0x8a5/0x1600 kernel/workqueue.c:2251 #2: ffffffff8bf795c0 (rcu_read_lock_bh){....}-{1:2}, at: __dev_queue_xmit+0x1da/0x3130 net/core/dev.c:4180 stack backtrace: CPU: 0 PID: 5 Comm: kworker/0:0 Not tainted 5.13.0-rc6-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: events ipvlan_process_multicast Call Trace: __dump_stack lib/dump_stack.c:79 [inline] dump_stack+0x141/0x1d7 lib/dump_stack.c:120 __in6_dev_get include/net/addrconf.h:313 [inline] __in6_dev_get include/net/addrconf.h:311 [inline] neigh_reduce drivers/net/vxlan.c:2167 [inline] vxlan_xmit+0x34d5/0x4c30 drivers/net/vxlan.c:2919 __netdev_start_xmit include/linux/netdevice.h:4944 [inline] netdev_start_xmit include/linux/netdevice.h:4958 [inline] xmit_one net/core/dev.c:3654 [inline] dev_hard_start_xmit+0x1eb/0x920 net/core/dev.c:3670 __dev_queue_xmit+0x2133/0x3130 net/core/dev.c:4246 ipvlan_process_multicast+0xa99/0xd70 drivers/net/ipvlan/ipvlan_core.c:287 process_one_work+0x98d/0x1600 kernel/workqueue.c:2276 worker_thread+0x64c/0x1120 kernel/workqueue.c:2422 kthread+0x3b1/0x4a0 kernel/kthread.c:313 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294 Fixes: f564f45c4518 ("vxlan: add ipv6 proxy support") Signed-off-by: Eric Dumazet Reported-by: syzbot Signed-off-by: David S. Miller Signed-off-by: Sasha Levin drivers/net/vxlan.c | 2 ++ 1 file changed, 2 insertions(+) culprit signature: e57a33f67a55ebc28f80f8650c1204fa16b6089fb502204f35d0ba49988f5a0e parent signature: 0973e9077f929475df76d949a408dc53ecdafceb7d892cad2d3e0633d6592fc6 revisions tested: 11, total time: 3h6m37.886043129s (build: 1h50m58.044071344s, test: 1h14m27.004682259s) first good commit: f80201ff7937fddb039716ba5948775b485d7646 vxlan: add missing rcu_read_lock() in neigh_reduce() recipients (to): ["davem@davemloft.net" "edumazet@google.com" "sashal@kernel.org"] recipients (cc): []