================================================================== BUG: KASAN: use-after-free in dev_put include/linux/netdevice.h:3676 [inline] BUG: KASAN: use-after-free in netdevice_event_work_handler+0x15b/0x1b0 drivers/infiniband/core/roce_gid_mgmt.c:626 Read of size 8 at addr ffff888098ba29c0 by task kworker/u4:5/2964 CPU: 1 PID: 2964 Comm: kworker/u4:5 Not tainted 4.19.211-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/26/2022 Workqueue: gid-cache-wq netdevice_event_work_handler Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x1fc/0x2ef lib/dump_stack.c:118 print_address_description.cold+0x54/0x219 mm/kasan/report.c:256 kasan_report_error.cold+0x8a/0x1b9 mm/kasan/report.c:354 kasan_report mm/kasan/report.c:412 [inline] __asan_report_load8_noabort+0x88/0x90 mm/kasan/report.c:433 dev_put include/linux/netdevice.h:3676 [inline] netdevice_event_work_handler+0x15b/0x1b0 drivers/infiniband/core/roce_gid_mgmt.c:626 process_one_work+0x864/0x1570 kernel/workqueue.c:2153 worker_thread+0x64c/0x1130 kernel/workqueue.c:2296 kthread+0x33f/0x460 kernel/kthread.c:259 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415 Allocated by task 21500: __do_kmalloc_node mm/slab.c:3689 [inline] __kmalloc_node+0x4c/0x70 mm/slab.c:3696 kmalloc_node include/linux/slab.h:557 [inline] kvmalloc_node+0x61/0xf0 mm/util.c:423 kvmalloc include/linux/mm.h:577 [inline] kvzalloc include/linux/mm.h:585 [inline] alloc_netdev_mqs+0x97/0xd50 net/core/dev.c:9152 __ip_tunnel_create+0x201/0x580 net/ipv4/ip_tunnel.c:267 ip_tunnel_init_net+0x330/0x990 net/ipv4/ip_tunnel.c:1035 ops_init+0xb3/0x410 net/core/net_namespace.c:129 setup_net+0x2c2/0x720 net/core/net_namespace.c:316 copy_net_ns+0x1f7/0x340 net/core/net_namespace.c:439 create_new_namespaces+0x3f6/0x7b0 kernel/nsproxy.c:107 unshare_nsproxy_namespaces+0xbd/0x1f0 kernel/nsproxy.c:206 ksys_unshare+0x36c/0x9a0 kernel/fork.c:2542 __do_sys_unshare kernel/fork.c:2610 [inline] __se_sys_unshare kernel/fork.c:2608 [inline] __x64_sys_unshare+0x2d/0x40 kernel/fork.c:2608 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe Freed by task 21500: __cache_free mm/slab.c:3503 [inline] kfree+0xcc/0x210 mm/slab.c:3822 kvfree+0x59/0x60 mm/util.c:452 device_release+0x76/0x210 drivers/base/core.c:1076 kobject_cleanup lib/kobject.c:662 [inline] kobject_release lib/kobject.c:691 [inline] kref_put include/linux/kref.h:70 [inline] kobject_put+0x28b/0x5d0 lib/kobject.c:708 put_device+0x1c/0x30 drivers/base/core.c:2267 free_netdev+0x309/0x410 net/core/dev.c:9265 __ip_tunnel_create+0x48f/0x580 net/ipv4/ip_tunnel.c:287 ip_tunnel_init_net+0x330/0x990 net/ipv4/ip_tunnel.c:1035 ops_init+0xb3/0x410 net/core/net_namespace.c:129 setup_net+0x2c2/0x720 net/core/net_namespace.c:316 copy_net_ns+0x1f7/0x340 net/core/net_namespace.c:439 create_new_namespaces+0x3f6/0x7b0 kernel/nsproxy.c:107 unshare_nsproxy_namespaces+0xbd/0x1f0 kernel/nsproxy.c:206 ksys_unshare+0x36c/0x9a0 kernel/fork.c:2542 __do_sys_unshare kernel/fork.c:2610 [inline] __se_sys_unshare kernel/fork.c:2608 [inline] __x64_sys_unshare+0x2d/0x40 kernel/fork.c:2608 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe The buggy address belongs to the object at ffff888098ba2480 which belongs to the cache kmalloc-4096 of size 4096 The buggy address is located 1344 bytes inside of 4096-byte region [ffff888098ba2480, ffff888098ba3480) The buggy address belongs to the page: page:ffffea000262e880 count:1 mapcount:0 mapping:ffff88813bff0dc0 index:0x0 compound_mapcount: 0 flags: 0xfff00000008100(slab|head) raw: 00fff00000008100 ffffea0001382688 ffffea000259b288 ffff88813bff0dc0 raw: 0000000000000000 ffff888098ba2480 0000000100000001 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff888098ba2880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888098ba2900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff888098ba2980: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888098ba2a00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888098ba2a80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================