netdevsim netdevsim0 netdevsim2 (unregistering): unset [1, 0] type 2 family 0 port 6081 - 0 netdevsim netdevsim0 netdevsim1 (unregistering): unset [1, 0] type 2 family 0 port 6081 - 0 netdevsim netdevsim0 netdevsim0 (unregistering): unset [1, 0] type 2 family 0 port 6081 - 0 ================================================================== BUG: KASAN: use-after-free in devlink_health_reporter_destroy+0x184/0x1d0 net/core/devlink.c:5476 Read of size 8 at addr ffff8880a1db0c20 by task kworker/u4:7/8798 CPU: 1 PID: 8798 Comm: kworker/u4:7 Not tainted 5.8.0-rc4-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: netns cleanup_net Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x18f/0x20d lib/dump_stack.c:118 print_address_description.constprop.0.cold+0xae/0x436 mm/kasan/report.c:383 __kasan_report mm/kasan/report.c:513 [inline] kasan_report.cold+0x1f/0x37 mm/kasan/report.c:530 devlink_health_reporter_destroy+0x184/0x1d0 net/core/devlink.c:5476 nsim_dev_health_exit+0x8b/0xe0 drivers/net/netdevsim/health.c:317 nsim_dev_reload_destroy+0x132/0x1e0 drivers/net/netdevsim/dev.c:1134 nsim_dev_reload_down+0x6e/0xd0 drivers/net/netdevsim/dev.c:712 devlink_reload+0xc1/0x3a0 net/core/devlink.c:2952 devlink_pernet_pre_exit+0xfb/0x190 net/core/devlink.c:9622 ops_pre_exit_list net/core/net_namespace.c:176 [inline] cleanup_net+0x451/0xa00 net/core/net_namespace.c:591 process_one_work+0x94c/0x1670 kernel/workqueue.c:2269 worker_thread+0x64c/0x1120 kernel/workqueue.c:2415 kthread+0x3b5/0x4a0 kernel/kthread.c:291 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:293 Allocated by task 6807: save_stack+0x1b/0x40 mm/kasan/common.c:48 set_track mm/kasan/common.c:56 [inline] __kasan_kmalloc.constprop.0+0xc2/0xd0 mm/kasan/common.c:494 kmem_cache_alloc_trace+0x14f/0x2d0 mm/slab.c:3551 kmalloc include/linux/slab.h:555 [inline] kzalloc include/linux/slab.h:669 [inline] __devlink_health_reporter_create+0x91/0x2f0 net/core/devlink.c:5359 devlink_health_reporter_create+0xa1/0x1d0 net/core/devlink.c:5431 nsim_dev_health_init+0x95/0x3a0 drivers/net/netdevsim/health.c:279 nsim_dev_probe+0xada/0xf80 drivers/net/netdevsim/dev.c:1086 really_probe+0x282/0x8a0 drivers/base/dd.c:525 driver_probe_device+0xfe/0x1d0 drivers/base/dd.c:701 __device_attach_driver+0x1c2/0x220 drivers/base/dd.c:807 bus_for_each_drv+0x15f/0x1e0 drivers/base/bus.c:431 __device_attach+0x28d/0x3f0 drivers/base/dd.c:873 bus_probe_device+0x1e4/0x290 drivers/base/bus.c:491 device_add+0xacf/0x1b00 drivers/base/core.c:2680 nsim_bus_dev_new drivers/net/netdevsim/bus.c:336 [inline] new_device_store+0x374/0x5c0 drivers/net/netdevsim/bus.c:215 bus_attr_store+0x72/0xa0 drivers/base/bus.c:122 sysfs_kf_write+0x110/0x160 fs/sysfs/file.c:138 kernfs_fop_write+0x268/0x490 fs/kernfs/file.c:315 vfs_write+0x2b0/0x6b0 fs/read_write.c:576 ksys_write+0x12d/0x250 fs/read_write.c:631 do_syscall_64+0x60/0xe0 arch/x86/entry/common.c:384 entry_SYSCALL_64_after_hwframe+0x44/0xa9 Freed by task 8798: save_stack+0x1b/0x40 mm/kasan/common.c:48 set_track mm/kasan/common.c:56 [inline] kasan_set_free_info mm/kasan/common.c:316 [inline] __kasan_slab_free+0xf5/0x140 mm/kasan/common.c:455 __cache_free mm/slab.c:3426 [inline] kfree+0x103/0x2c0 mm/slab.c:3757 devlink_health_reporter_free net/core/devlink.c:5449 [inline] devlink_health_reporter_put+0xb7/0xf0 net/core/devlink.c:5456 __devlink_health_reporter_destroy net/core/devlink.c:5463 [inline] devlink_health_reporter_destroy+0x143/0x1d0 net/core/devlink.c:5475 nsim_dev_health_exit+0x8b/0xe0 drivers/net/netdevsim/health.c:317 nsim_dev_reload_destroy+0x132/0x1e0 drivers/net/netdevsim/dev.c:1134 nsim_dev_reload_down+0x6e/0xd0 drivers/net/netdevsim/dev.c:712 devlink_reload+0xc1/0x3a0 net/core/devlink.c:2952 devlink_pernet_pre_exit+0xfb/0x190 net/core/devlink.c:9622 ops_pre_exit_list net/core/net_namespace.c:176 [inline] cleanup_net+0x451/0xa00 net/core/net_namespace.c:591 process_one_work+0x94c/0x1670 kernel/workqueue.c:2269 worker_thread+0x64c/0x1120 kernel/workqueue.c:2415 kthread+0x3b5/0x4a0 kernel/kthread.c:291 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:293 The buggy address belongs to the object at ffff8880a1db0c00 which belongs to the cache kmalloc-512 of size 512 The buggy address is located 32 bytes inside of 512-byte region [ffff8880a1db0c00, ffff8880a1db0e00) The buggy address belongs to the page: page:ffffea0002876c00 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff8880a1db0800 flags: 0xfffe0000000200(slab) raw: 00fffe0000000200 ffffea00029fcd88 ffffea00029e8b48 ffff8880aa000a80 raw: ffff8880a1db0800 ffff8880a1db0000 0000000100000003 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8880a1db0b00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff8880a1db0b80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff8880a1db0c00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8880a1db0c80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8880a1db0d00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================